Objective: To establish a novel approach for quick and highly efficient verification of human gene imprinting. Methods: A pair of dye-labelled probes, 5' nuclease assay was combined with RT-PCR to determine the ge...Objective: To establish a novel approach for quick and highly efficient verification of human gene imprinting. Methods: A pair of dye-labelled probes, 5' nuclease assay was combined with RT-PCR to determine the genotype of a transcribed single nucleotide polymorphism (SNP) rs705(C>T) of a known imprinted gene, small nuclear ribonucleotide protein N (SNRPN), on both genomic DNA and cDNA of human lym-phoblast cell lines. Results: Allele discrimination showed a clear monoallelic expression pattern of SNRPN, which was confirmed by RT-PCR based restriction fragment length polymorphism (RFLPs). Pedigree analysis verified the paternal origin of expressed allele, which was in consistency with previous report. Conclusion: Transcribed SNP is an ideal marker for detecting gene imprinting by 5' nuclease assay. This approach also may be used to discover differential allele expression of non-imprinted genes, finding out gene cis-acting functional polymorphism.展开更多
Objective: To analyze the genomic structure of SNC6, a progesterone\|receptor associated protein gene and its regulatory elements in its 5'\|flanking region. Methods: Genomic sequence from GenBank database (access...Objective: To analyze the genomic structure of SNC6, a progesterone\|receptor associated protein gene and its regulatory elements in its 5'\|flanking region. Methods: Genomic sequence from GenBank database (accession number: Z98048) covering the whole SNC6 gene was used to analyze the genomic structure of SNC6 and design primers for PCR amplification of its 5'\|flanking region. A 1894 bp fragment of the 5'\|flanking region \{(-1814\} to +75) was cloned by PCR using genomic DNA from a healthy donor peripheral blood lymphocyte as template. This fragment, as well as 3 shorter derivative fragments (1423 bp, 632 bp and 416 bp, which correspond to -1344 to +75, -552 to +75 and -337 to +75 respectively), were subcloned into pGL2 series luciferase reporter vectors. These constructs were introduced into colorectal cancer cell line SW620 for transient expression of reporter gene and luciferase activities were measured. Results: The genomic structure analysis showed there are 12 exons for SNC6 gene, which spans 32017 bp (nt71529 to nt39513 in Z98048 sequence). All transfected SW620 cells with the above 5\|flanking region\|containing constructs showed luciferase activities. The highest luciferase activities were measured in transfected cells with vectors containing 1894 bp fragments, and the lowest luciferase activities were measured in transfected cells with vectors containing 416 bp fragments. Luciferase activities were higher in transfected cells with vectors containing 632 bp fragments than that in transfected cells with vectors containing 1423 bp fragments. Conclusion: The basic transcription\|promoting element (promoter) for SNC6 expression resides between 0 to -337, and two transcription\|enhancing elements (enhancer) resides between -337 to -552 and -1344 to -1814, whereas one transcription\|inhibiting element (silencer) exists between -552 to -1344.展开更多
Introduction: 5-Fluorouracil (5-FU) is the basis of most combination chemotherapies for gastrointestinal tumors. It is generally well tolerated, but side-effects might require dose-adjustment. As adverse events are no...Introduction: 5-Fluorouracil (5-FU) is the basis of most combination chemotherapies for gastrointestinal tumors. It is generally well tolerated, but side-effects might require dose-adjustment. As adverse events are not specific to the 5-FU component of the chemotherapy-combination, i.e. neutropenia, diarrhea or cardiotoxicity, the knowledge of 5-FU serum levels might help to attribute these side effects to the 5-FU compound. The optimal concentration-range (AUC, area under the curve) has been described to be within 20-25 mgh/l. The aim of this study was to analyse the intra- and interindividual variability of 5-FU AUC-levels in patients with 5-FU infusion therapy. Methods: 230 blood samples were obtained from 31 different gastrointestinal cancer patients (esophagus (8), stomach (10), ileum (1), colorectum (12)) treated with 5-FU-infusional regimes, based on a 24- or 48-hour AIO treatment-schedule. 5-FU plasma concentrations were measured using an immunolinked Elisa assay (Saladax 5-FU PCMTM). Intra- and interindividual differences were analysed before (0 h;n = 115), at 2 - 3 hours after the start of infusional 5-FU treatment (n = 19) (early sampling) and towards the end of the infusion (n = 96) (late sampling). Results: Early blood sampling resulted in low 5-FU plasma concentrations (541 ± 127 g/ml) due to saline prefilling (2 - 3 ml) of the Baxter pump. Blood sampling at the later time-point resulted in reproducible values (971 ± 81 ng/ml). 5-FU concentrations were dose-dependent with low intra- and interindividual variability. However, care has to be taken, as the results can be influenced by inaccurate blood sampling: too early or late sampling (when the folfusor-pump is empty), delayed centrifugation of the tube or hemolysis. Conclusions: With critical analysis of the measurements and correct performance of blood sampling, the measurement of 5-FU plasma concentrations with the immunoassay may in the future allow to optimize 5-FU dosing and to identify the cause of toxicity. Changes of 5-FU clearance in long-term therapy still have to be studied.展开更多
AIM: To investigate serum insulin-like growth factor-binding protein 5 (IGFBP-5) levels and intestinal IGFBP-5 expression in patients with Crohn’s disease (CD).
AIM:To determine whether expression of certain enzymes related to 5-fluorouracil(5-FU)metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma(CCA).METHODS:The histoculture drug response assay(HDRA)was performe...AIM:To determine whether expression of certain enzymes related to 5-fluorouracil(5-FU)metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma(CCA).METHODS:The histoculture drug response assay(HDRA)was performed using surgically resected CCA tissues.Tumor cell viability was determined morphologically with hematoxylin and eosin-and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling-stained tissues.The mRNA expression of thymidine phosphorylase(TP),orotate phosphoribosyl transferase(OPRT),thymidylate synthase(TS),and dihydropyrimidine dehydrogenase(DPD)was determined with realtime reverse transcriptase-polymerase chain reaction.The levels of gene expression and the sensitivity to 5-FU were evaluated.RESULTS:Twenty-three CCA tissues were obtained from patients who had been diagnosed with intrahepatic CCA and who underwent surgical resection at Srinagarind Hospital,Khon Kaen University from 2007 to 2009.HDRA was used to determine the response of these CCA tissues to 5-FU.Based on the dose-response curve,200μg/mL 5-FU was selected as the test concentration.The percentage of inhibition index at the median point was selected as the cut-off point to differentiate the responding and non-responding tumors to 5-FU.When the relationship between TP,OPRT,TS and DPD mRNA expression levels and the sensitivity of CCA tissues to 5-FU was examined,only OPRT mRNA expression was significantly correlated with the response to 5-FU.The mean expression level of OPRT was significantly higher in the responder group compared to the non-responder group(0.41±0.25 vs 0.22±0.12,P<0.05).CONCLUSION:OPRT mRNA expression may be a useful predictor of 5-FU chemosensitivity of CCA.Whether OPRT mRNA could be used to predict the success of 5-FU chemotherapy in CCA patients requires confirmation in patients.展开更多
Phytochemical studies and antioxidant activities were carried out on n-hexane, ethyl acetate, ethanol and methanol extracts of the leaves of Lippia rugosa A. Chev (Verbenaceae), a medicinal plant used traditionally in...Phytochemical studies and antioxidant activities were carried out on n-hexane, ethyl acetate, ethanol and methanol extracts of the leaves of Lippia rugosa A. Chev (Verbenaceae), a medicinal plant used traditionally in the Cameroonian savannah’s region to protect foodstuffs and to cure degenerative diseases. Results indicated that theses extracts contain terpenoids, phenolic and flavonoid compounds. Except the n-hexane extract, all of the obtained extracts exhibit antioxidant activities with the ethanol extract being the most effective with an inhibition percentage of 85.668% ± 1.233% and an inhibition concentration (IC<sub>50</sub>) of 58 μg/ml (R<sup>2</sup> = 0.987, P < 0.01) at a concentration of 100 mg/ml. Chromatographic separation on silica gel of the ethanol extract led to the isolation of a pure organic compound which was characterized as 7-hydroxy-5,6,4'-trimethox- yflavone by extensive 1D and 2D NMR spectroscopy, a flavonoid exhibiting antioxidative activity with an inhibitory percentage of 25.506% ± 0.205% and inhibition concentration (IC<sub>50</sub>) of 221 μg/ml (R<sup>2</sup> = 0.966, P < 0.01). This is the first time that 7-hydroxy-5,6,4'-trimethoxyflavone is being isolated from L. rugosa and its antioxidant activity evaluated.展开更多
Para-phenylenediamine (PPD), tile main toxic ingredients of hair dyes, have been used by millions of consumers to improve their appearance. Stone Hair Dye (SHD) mainly contain PPD. SHD and PPD were evaluated by 3-...Para-phenylenediamine (PPD), tile main toxic ingredients of hair dyes, have been used by millions of consumers to improve their appearance. Stone Hair Dye (SHD) mainly contain PPD. SHD and PPD were evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazdium bromide or MTT assay, which measures mitochondria metabolism in the entire cell culture and provides information about the percentage of cell survival. Utilizing the MTT assay, the cytotoxicity of SHD and PPD was determining on SH Sy5y culture from nervous system of rat. The short term exposure SH Sy5y culture were incubated with various aqueous solutions of different concentrations of SHD and PPD, and the LC50 of SHD and para-phenylenediamine was found to be 9.15 and 12.4 mg/ml. With increasing the concentration, cytotoxicity effect increase in PPD and SHD. There is a significant differences (P〈0.01) of cytotoxicity among concentrations used. It concluded that in vitro assay could give important information of the mechanism of toxicity at low dosages.展开更多
Schwann cell proliferation,migration and remyelination of regenerating axons contribute to regeneration after peripheral nervous system injury.Lithium promotes remyelination by Schwann cells and improves peripheral ne...Schwann cell proliferation,migration and remyelination of regenerating axons contribute to regeneration after peripheral nervous system injury.Lithium promotes remyelination by Schwann cells and improves peripheral nerve regeneration.However,whether lithium modulates other phenotypes of Schwann cells,especially their proliferation and migration remains elusive.In the current study,primary Schwann cells from rat sciatic nerve stumps were cultured and exposed to 0,5,10,15,or 30 mM lithium chloride(LiCl)for 24 hours.The effects of LiCl on Schwann cell proliferation and migration were examined using the Cell Counting Kit-8,5-ethynyl-2′-deoxyuridine,Transwell and wound healing assays.Cell Counting Kit-8 and 5-ethynyl-2′-deoxyuridine assays showed that 5,10,15,and 30 mM LiCl significantly increased the viability and proliferation rate of Schwann cells.Transwell-based migration assays and wound healing assays showed that 10,15,and 30 mM LiCl suppressed the migratory ability of Schwann cells.Furthermore,the effects of LiCl on the proliferation and migration phenotypes of Schwann cells were mostly dose-dependent.These data indicate that lithium treatment significantly promotes the proliferation and inhibits the migratory ability of Schwann cells.This conclusion will inform strategies to promote the repair and regeneration of peripheral nerves.All of the animal experiments in this study were ethically approved by the Administration Committee of Experimental Animal Center of Nantong University,China(approval No.20170320-017)on March 2,2017.展开更多
Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1(NMDAR1) plays an important role in t...Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1(NMDAR1) plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D(-)-2-amino-5-phosphonopentanoic acid(AP-5),or both once daily for 15 days.Compared with injured drug na?ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity(as assessed by immunohistochemistry) and protein(as determined by western blot assay) in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia.展开更多
AIM: To address the possibility that insulin-like growth factor (IGF)-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS: Huh-6 and HepG2, human hepato...AIM: To address the possibility that insulin-like growth factor (IGF)-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS: Huh-6 and HepG2, human hepatoblastoma cell lines, were used. IGF-Ⅱ was added to the medium deprived of serum. Western blot analysis was performed to clarify the expression of IGF-Ⅰ receptor (IGF-IR). Inhibitors of IGF-IR (piclopodophyllin, PPP), phosphatidyl-inositol (PI) 3-kinase (LY294002 and Wortmannin), or mitogen-activated protein (MAP) kinase (PD98059) were added to unveil the signaling pathway of IGF-Ⅱ. Cells were analyzed morphologically with hematoxylin-eosin staining to reveal the mechanism of suppression of cell proliferation. RESULTS: IGF-Ⅱ stimulated cells proliferated to 2.7 (269% ± 76%) (mean ± SD) (Huh-6) and 2.1 (211% ± 85%) times (HepG2). IGF-IR was expressed in Huh-6 and HepG2. PPP suppressed the cell number to 44% ± 11% (Huh-6) and 39% ± 5% (HepG2). LY294002 and Wortmannin suppressed the cell number to 30% ± 5% (Huh-6), 44% ± 0.4% (HepG2), 49% ± 1.0% (Huh-6) and 46% ± 1.1% (HepG2), respectively. PD98059 suppressed the cell number to 33% ± 11% for HepG2 but not for Huh-6. When cell proliferation was prohibited, many Huh-6 and HepG2 cells were dead with pyknotic or fragmented nuclei, suggesting apoptosis. CONCLUSION: IGF- Ⅱ was shown to be a growth factor of hepatoblastoma via IGF-Ⅰ receptor and PI3 kinase which were good candidates for target of molecular therapy.展开更多
AIM: To identify kinases involved in phenotype regulation of vascular endothelial cells(VECs): Proproliferative G-protein signaling 5(RGS5)^(high)(typeⅠ) vs anti-proliferative RGS5^(low)(typeⅡ) VECs.METHODS: Proteom...AIM: To identify kinases involved in phenotype regulation of vascular endothelial cells(VECs): Proproliferative G-protein signaling 5(RGS5)^(high)(typeⅠ) vs anti-proliferative RGS5^(low)(typeⅡ) VECs.METHODS: Proteomic kinase assays were performed to identify the crucial kinase involved in the phenotype regulation of human VECs using typeⅠ VECs, which promotes the proliferation of human vascular smooth muscle cells(VSMCs), and typeⅡ VECs, which suppress the proliferation of human VSMCs. The assays were performed using multiple pairs of typeⅠ and typeⅡ VECs to obtain the least number of candidates. The involvement of the candidate kinases was verified by evaluating the effects of their specific inhibitors on the phenotype regulation of human VECs as well as the expression levels of regulator of RGS5, which is the causative gene for the "typeⅡ to typeⅠ" phenotype conversion of human VECs. RESULTS: p38α mitogen-activated protein kinase(p38α MAPK) was the only kinase that showed distinctive activities between typeⅠ and typeⅡ VECs: p38α MAPK activities were low and high in type-Ⅰand typeⅡ VECs, respectively. We found that an enforced expression of RGS5 indeed lowered p38α MAPK activitiesin typeⅡ VECs. Furthermore, treatments with a p38α MAPK inhibitor nullified the anti-proliferative potential in typeⅡ VECs. Interestingly, MAPK inhibitor treatments enhanced the induction of RGS5 gene. Thus, there is a vicious cycle between "RGS5 induction" and "p38α MAPK inhibition", which can explain the unidirectional process in the stress-induced "typeⅡ to typeⅠ" conversions of human VECs. To understand the upstream signaling of RGS5, which is known as an inhibitory molecule against the G protein-coupled receptor(GPCR)-mediated signaling, we examined the effects of RGS5 overexpression on the signaling events from sphingosine-1-phosphate(S1P) to N-cadherin, because S1 P receptors belong to the GPCR family gene and N-cadherin, one of their downstream effectors, is reportedly involved in the regulation of VEC-VSMC interactions. We found that RGS5 specifically bound with S1P1. Moreover, N-cadherin localization at intercellular junctions in typeⅡ VECs was abolished by "RGS5 overexpression" and "p38α MAPK inhibition".CONCLUSION: p38α MAPK plays crucial roles in "type-Ⅰ vs type-Ⅱ" phenotype regulations of human VECs at the downstream of RGS5.展开更多
The recently developed yeast three-hybrid system is a powerful tool for analyzing RNA-protein interactions in vivo. However, large numbers of false positives are frequently met due to bait RNA-independent activation o...The recently developed yeast three-hybrid system is a powerful tool for analyzing RNA-protein interactions in vivo. However, large numbers of false positives are frequently met due to bait RNA-independent activation of the reporter gene in the library screening using this system. In this report, we coupled the colony color assay with the 5FOA (5-fluoroorotic acid) negative selection in the library screening, and found that this coupled method effectively eliminated bait RNA-independent false positives and hence greatly improved library screening efficiency. We used this method successfully in isolation of cDNA of an RNA-binding protein that might play important roles in certain cellular process. This improvement will facilitate the use of the yeast three-hybrid system in analyzing RNA-protein interaction.展开更多
OBJECTIVES: To study the concentration, distribution and expression of IL-5 in nasal polyp tissues and explore its significance in micro-environment differentiation of eosinophil accumulation. METHODS: The concentrati...OBJECTIVES: To study the concentration, distribution and expression of IL-5 in nasal polyp tissues and explore its significance in micro-environment differentiation of eosinophil accumulation. METHODS: The concentration and expression of IL-5 in nasal polyp tissues of 40 patients were determined by ELISA and immunohistochemistry and inferior turbinate mucosa from patients with nasal polyps and healthy volunteers were used as control. RESULTS: IL-5 concentration in polyp tissues was significantly higher than that in turbinate mucosa (P 0.05). IL-5 concentrations in polyp tissues were markedly higher in patients with allergic rhinitis compared with those without (P 0.05). 80.1% of the eosinophils were positive for IL-5 and 90.9% of IL-5 positive cells were eosinophils. Only 3.7% of lymphocytes and neutrophils were positive for IL-5; IL-5 was not detectable in epithelial cells. IL-5 expression in eosinophils of polyp tissues was remarkably stronger than that of the turbinate mucosa (P 0.05). IL-5 expression of eosinophils in polyp tissue was significantly stronger in patients with allergic rhinitis compared with those without (P 0.05). CONCLUSION: IL-5 is the key cytokine in eosinophilic pathologic mechanisms in nasal polyp tissues.展开更多
Paclitaxel(PTX),methotrexate(MTX),and 5-fluorouracil(5-FU)are commonly-used small molecule anti-tumor drugs for breast cancer.Unfortunately,drug resistance occurs with long-term treatment or excessive use,and the high...Paclitaxel(PTX),methotrexate(MTX),and 5-fluorouracil(5-FU)are commonly-used small molecule anti-tumor drugs for breast cancer.Unfortunately,drug resistance occurs with long-term treatment or excessive use,and the high concentrations of PTX,MTX,and 5-FU in patients may lead to side effects with dose-limiting toxicities,such as myelosuppression,hepatotoxicity,and peripheral neuropathy.Therefore,concentration monitoring of PTX,MTX,and 5-FU in clinical treatment is very important.We prepared highly sensitive and specific monoclonal antibodies using several haptens,and established a multiple paper-based sensor utilizing optical signals of gold nanoparticles,which simultaneously detected PTX,MTX,and 5-FU in human plasma or urine with 10 min.A portable scanner for quantitative detection in plasma and urine samples was used,and the calculated limit of detection(cLOD)values were 0.002 and 0.142μg/mL for PTX,0.187 and 0.976 ng/mL for MTX,and 0.057 and 0.128μg/mL for 5-FU,respectively.In the recovery test,the recovery rates and the coefficient of variation were 85.84%–108.81%and 1.23%–8.80%,respectively,indicating the reliability and accuracy of the multiple gold immunochromatographic strip(GIS).In addition,for the determination of collected clinical plasma samples,the correlation between the test data of the multiple GIS and liquid chromatography–tandem mass spectrometry(LC–MS/MS)was good.Therefore,the developed multiple GIS could be applied to the rapid detection of PTX,MTX,and 5-FU in different clinical samples.展开更多
OBJECTIVE: To screen the 5' regulatory region of the aldose reductase (AR) gene for genetic variabilities causing changes in protein expression and affecting the promoter function. METHODS: The screenings were car...OBJECTIVE: To screen the 5' regulatory region of the aldose reductase (AR) gene for genetic variabilities causing changes in protein expression and affecting the promoter function. METHODS: The screenings were carried out by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). All SSCP variants were submitted for DNA sequencing and inserted into the plasmid chloromycetin acetyl transferase (CAT) enhancer vector. The constructs were used to transfect Hela cells, and CAT assays were performed to assess promoter activity. Gel mobility shift and footprinting assays were also performed to determine the interaction between the DNA and nuclear proteins. RESULTS: Two polymorphisms, C (-106) T and C (-12) G, were identified in the regulatory region in 123 Chinese control subjects and 145 patients with type 2 diabetes mellitus. The frequencies of genotypes WT/WT, WT/C (-12) G and WT/C (-106) T were not significantly different between the subjects and patients. In the patients with and without retinopathy, frequencies of WT/C (-106) T were 31.5% and 17.5% (P 0.05) respectively. The total frequency of WT/C (-12) G and WT/C (-106) T in patients with retinopathy was 41.8%, significantly higher than that (20.0%) in patients without retinopathy (P展开更多
New series of pyrazolo[1,5-α]pyrimidine derivatives 7a-i,11a-c and Schiff bases 13a-c were synthesized and screened for their in vitro antitumor activity against three human carcinoma cell lines,namely colorectal car...New series of pyrazolo[1,5-α]pyrimidine derivatives 7a-i,11a-c and Schiff bases 13a-c were synthesized and screened for their in vitro antitumor activity against three human carcinoma cell lines,namely colorectal carcinoma(HCT116),prostate adenocarcinoma(PC-3) and liver carcinoma(HepG-2) using MTT cytotoxicity assay at 100 μg/mL.Some of the tested compounds displayed good anticancer activities against HCT-116 and PC-3 cells.Whereas,compounds 7d and 11 a showed better antitumor activity than the rest of the compounds against both cell lines.A structure-activity relationship(SAR) has been discussed and structures of the newly synthesized compounds were confirmed by different spectral data(MS,IR,^1H NMR and ^13C NMR) and elemental analysis.展开更多
Objective:To investigate the anticancer activity of the total flavonoids isolated from a herbal formula,Xianhe Yanling Recipe(仙鹤延龄方),a recipe commonly used in cancer patients in China.Methods: The in vitro an...Objective:To investigate the anticancer activity of the total flavonoids isolated from a herbal formula,Xianhe Yanling Recipe(仙鹤延龄方),a recipe commonly used in cancer patients in China.Methods: The in vitro anticancer activity of the total flavonoids was determined using the 3-(4,5-dimethylthiazole-2-yl)-2,5- diphenyltetrazolium bromide(MTT) assay on three cancer cell lines:MCF-7(a human breast adenocarcinoma cell line),HepG-2(a human hepatocellular carcinoma cell line) and ES-2(a human ovarian cancer cell line). The in vivo anticancer effect of the total flavonoids was assessed in a mouse tumor model bearing H22-induced hepatocellular carcinoma,and cisplatin was used as a positive control.Results:The total flavonoids exerted a powerful inhibitory effect on the three cell lines,with 50%inhibiting concentrations(IC_(50)) of 24.948,31.569 and 6.923μg/mL,respectively.In vivo studies showed that the total flavonoids had dose-dependent inhibitory effects on hepatocellular carcinoma in mice.Conclusion:The total flavonoids from Xianhe Yanling Recipe have potential anticancer activity,and further researches and development are warranted.展开更多
Neuronal growth inhibitory factor (GIF), named Metallothioneins-III (MT-III), is the first protein validated to be capable of inhibiting the growth of neurons in nervous system. We have detected the effects of recombi...Neuronal growth inhibitory factor (GIF), named Metallothioneins-III (MT-III), is the first protein validated to be capable of inhibiting the growth of neurons in nervous system. We have detected the effects of recombinant GIF on the growth of neuroblastoma SY5Y and pheochro-mocytoma PC12 by the MTT (Thiazolyl blue) reduction as-say. Recombinant GIF inhibited PC12 in vitro; the inhibitory rate was about 25% when GIF was at 100 mg/L; and the inhibitory rate was about 50% when GIF was at 300 mg/L. It is shown that PC12 could serve as a proper model for de-tecting neuronal growth inhibitory activity of GIF. Recom-binant GIF did not inhibit neuroblastoma SY5Y in vitro, a common model of neuroma; it is also shown that GIF could not inhibit neuromata extensively. The reason for GIF inhib-iting PC12 may be that PC12 have some properties of cho-linergic neuron. It must play an important role in discover-ing the mechanism of GIF’s neuronal growth inhibitory ac-tivity.展开更多
文摘Objective: To establish a novel approach for quick and highly efficient verification of human gene imprinting. Methods: A pair of dye-labelled probes, 5' nuclease assay was combined with RT-PCR to determine the genotype of a transcribed single nucleotide polymorphism (SNP) rs705(C>T) of a known imprinted gene, small nuclear ribonucleotide protein N (SNRPN), on both genomic DNA and cDNA of human lym-phoblast cell lines. Results: Allele discrimination showed a clear monoallelic expression pattern of SNRPN, which was confirmed by RT-PCR based restriction fragment length polymorphism (RFLPs). Pedigree analysis verified the paternal origin of expressed allele, which was in consistency with previous report. Conclusion: Transcribed SNP is an ideal marker for detecting gene imprinting by 5' nuclease assay. This approach also may be used to discover differential allele expression of non-imprinted genes, finding out gene cis-acting functional polymorphism.
文摘Objective: To analyze the genomic structure of SNC6, a progesterone\|receptor associated protein gene and its regulatory elements in its 5'\|flanking region. Methods: Genomic sequence from GenBank database (accession number: Z98048) covering the whole SNC6 gene was used to analyze the genomic structure of SNC6 and design primers for PCR amplification of its 5'\|flanking region. A 1894 bp fragment of the 5'\|flanking region \{(-1814\} to +75) was cloned by PCR using genomic DNA from a healthy donor peripheral blood lymphocyte as template. This fragment, as well as 3 shorter derivative fragments (1423 bp, 632 bp and 416 bp, which correspond to -1344 to +75, -552 to +75 and -337 to +75 respectively), were subcloned into pGL2 series luciferase reporter vectors. These constructs were introduced into colorectal cancer cell line SW620 for transient expression of reporter gene and luciferase activities were measured. Results: The genomic structure analysis showed there are 12 exons for SNC6 gene, which spans 32017 bp (nt71529 to nt39513 in Z98048 sequence). All transfected SW620 cells with the above 5\|flanking region\|containing constructs showed luciferase activities. The highest luciferase activities were measured in transfected cells with vectors containing 1894 bp fragments, and the lowest luciferase activities were measured in transfected cells with vectors containing 416 bp fragments. Luciferase activities were higher in transfected cells with vectors containing 632 bp fragments than that in transfected cells with vectors containing 1423 bp fragments. Conclusion: The basic transcription\|promoting element (promoter) for SNC6 expression resides between 0 to -337, and two transcription\|enhancing elements (enhancer) resides between -337 to -552 and -1344 to -1814, whereas one transcription\|inhibiting element (silencer) exists between -552 to -1344.
文摘Introduction: 5-Fluorouracil (5-FU) is the basis of most combination chemotherapies for gastrointestinal tumors. It is generally well tolerated, but side-effects might require dose-adjustment. As adverse events are not specific to the 5-FU component of the chemotherapy-combination, i.e. neutropenia, diarrhea or cardiotoxicity, the knowledge of 5-FU serum levels might help to attribute these side effects to the 5-FU compound. The optimal concentration-range (AUC, area under the curve) has been described to be within 20-25 mgh/l. The aim of this study was to analyse the intra- and interindividual variability of 5-FU AUC-levels in patients with 5-FU infusion therapy. Methods: 230 blood samples were obtained from 31 different gastrointestinal cancer patients (esophagus (8), stomach (10), ileum (1), colorectum (12)) treated with 5-FU-infusional regimes, based on a 24- or 48-hour AIO treatment-schedule. 5-FU plasma concentrations were measured using an immunolinked Elisa assay (Saladax 5-FU PCMTM). Intra- and interindividual differences were analysed before (0 h;n = 115), at 2 - 3 hours after the start of infusional 5-FU treatment (n = 19) (early sampling) and towards the end of the infusion (n = 96) (late sampling). Results: Early blood sampling resulted in low 5-FU plasma concentrations (541 ± 127 g/ml) due to saline prefilling (2 - 3 ml) of the Baxter pump. Blood sampling at the later time-point resulted in reproducible values (971 ± 81 ng/ml). 5-FU concentrations were dose-dependent with low intra- and interindividual variability. However, care has to be taken, as the results can be influenced by inaccurate blood sampling: too early or late sampling (when the folfusor-pump is empty), delayed centrifugation of the tube or hemolysis. Conclusions: With critical analysis of the measurements and correct performance of blood sampling, the measurement of 5-FU plasma concentrations with the immunoassay may in the future allow to optimize 5-FU dosing and to identify the cause of toxicity. Changes of 5-FU clearance in long-term therapy still have to be studied.
文摘AIM: To investigate serum insulin-like growth factor-binding protein 5 (IGFBP-5) levels and intestinal IGFBP-5 expression in patients with Crohn’s disease (CD).
基金Supported by The Research Team Strengthening Grant,National Genetic Engineering and Biotechnology Center,National Science and Technology Development Agency,ThailandThe Liver Fluke and Cholangiocarcinoma Research Center,Faculty of Medicine,Khon Kaen University,Thailand(to Chaiyagool J)
文摘AIM:To determine whether expression of certain enzymes related to 5-fluorouracil(5-FU)metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma(CCA).METHODS:The histoculture drug response assay(HDRA)was performed using surgically resected CCA tissues.Tumor cell viability was determined morphologically with hematoxylin and eosin-and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling-stained tissues.The mRNA expression of thymidine phosphorylase(TP),orotate phosphoribosyl transferase(OPRT),thymidylate synthase(TS),and dihydropyrimidine dehydrogenase(DPD)was determined with realtime reverse transcriptase-polymerase chain reaction.The levels of gene expression and the sensitivity to 5-FU were evaluated.RESULTS:Twenty-three CCA tissues were obtained from patients who had been diagnosed with intrahepatic CCA and who underwent surgical resection at Srinagarind Hospital,Khon Kaen University from 2007 to 2009.HDRA was used to determine the response of these CCA tissues to 5-FU.Based on the dose-response curve,200μg/mL 5-FU was selected as the test concentration.The percentage of inhibition index at the median point was selected as the cut-off point to differentiate the responding and non-responding tumors to 5-FU.When the relationship between TP,OPRT,TS and DPD mRNA expression levels and the sensitivity of CCA tissues to 5-FU was examined,only OPRT mRNA expression was significantly correlated with the response to 5-FU.The mean expression level of OPRT was significantly higher in the responder group compared to the non-responder group(0.41±0.25 vs 0.22±0.12,P<0.05).CONCLUSION:OPRT mRNA expression may be a useful predictor of 5-FU chemosensitivity of CCA.Whether OPRT mRNA could be used to predict the success of 5-FU chemotherapy in CCA patients requires confirmation in patients.
文摘Phytochemical studies and antioxidant activities were carried out on n-hexane, ethyl acetate, ethanol and methanol extracts of the leaves of Lippia rugosa A. Chev (Verbenaceae), a medicinal plant used traditionally in the Cameroonian savannah’s region to protect foodstuffs and to cure degenerative diseases. Results indicated that theses extracts contain terpenoids, phenolic and flavonoid compounds. Except the n-hexane extract, all of the obtained extracts exhibit antioxidant activities with the ethanol extract being the most effective with an inhibition percentage of 85.668% ± 1.233% and an inhibition concentration (IC<sub>50</sub>) of 58 μg/ml (R<sup>2</sup> = 0.987, P < 0.01) at a concentration of 100 mg/ml. Chromatographic separation on silica gel of the ethanol extract led to the isolation of a pure organic compound which was characterized as 7-hydroxy-5,6,4'-trimethox- yflavone by extensive 1D and 2D NMR spectroscopy, a flavonoid exhibiting antioxidative activity with an inhibitory percentage of 25.506% ± 0.205% and inhibition concentration (IC<sub>50</sub>) of 221 μg/ml (R<sup>2</sup> = 0.966, P < 0.01). This is the first time that 7-hydroxy-5,6,4'-trimethoxyflavone is being isolated from L. rugosa and its antioxidant activity evaluated.
文摘Para-phenylenediamine (PPD), tile main toxic ingredients of hair dyes, have been used by millions of consumers to improve their appearance. Stone Hair Dye (SHD) mainly contain PPD. SHD and PPD were evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazdium bromide or MTT assay, which measures mitochondria metabolism in the entire cell culture and provides information about the percentage of cell survival. Utilizing the MTT assay, the cytotoxicity of SHD and PPD was determining on SH Sy5y culture from nervous system of rat. The short term exposure SH Sy5y culture were incubated with various aqueous solutions of different concentrations of SHD and PPD, and the LC50 of SHD and para-phenylenediamine was found to be 9.15 and 12.4 mg/ml. With increasing the concentration, cytotoxicity effect increase in PPD and SHD. There is a significant differences (P〈0.01) of cytotoxicity among concentrations used. It concluded that in vitro assay could give important information of the mechanism of toxicity at low dosages.
基金supported by the National Natural Science Foundation of China,No.81970820(to HX)
文摘Schwann cell proliferation,migration and remyelination of regenerating axons contribute to regeneration after peripheral nervous system injury.Lithium promotes remyelination by Schwann cells and improves peripheral nerve regeneration.However,whether lithium modulates other phenotypes of Schwann cells,especially their proliferation and migration remains elusive.In the current study,primary Schwann cells from rat sciatic nerve stumps were cultured and exposed to 0,5,10,15,or 30 mM lithium chloride(LiCl)for 24 hours.The effects of LiCl on Schwann cell proliferation and migration were examined using the Cell Counting Kit-8,5-ethynyl-2′-deoxyuridine,Transwell and wound healing assays.Cell Counting Kit-8 and 5-ethynyl-2′-deoxyuridine assays showed that 5,10,15,and 30 mM LiCl significantly increased the viability and proliferation rate of Schwann cells.Transwell-based migration assays and wound healing assays showed that 10,15,and 30 mM LiCl suppressed the migratory ability of Schwann cells.Furthermore,the effects of LiCl on the proliferation and migration phenotypes of Schwann cells were mostly dose-dependent.These data indicate that lithium treatment significantly promotes the proliferation and inhibits the migratory ability of Schwann cells.This conclusion will inform strategies to promote the repair and regeneration of peripheral nerves.All of the animal experiments in this study were ethically approved by the Administration Committee of Experimental Animal Center of Nantong University,China(approval No.20170320-017)on March 2,2017.
基金supported by the Youth Shihezi University Applied Basic Research Project of China,No.2015ZRKYQ-LH19
文摘Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1(NMDAR1) plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D(-)-2-amino-5-phosphonopentanoic acid(AP-5),or both once daily for 15 days.Compared with injured drug na?ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity(as assessed by immunohistochemistry) and protein(as determined by western blot assay) in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia.
基金Supported by the Japan Society for the Promotion of Science (JSPS) (16590577) and the Kawano Masanori Memorial Foundation for Promotion of Pediatrics (15-6)
文摘AIM: To address the possibility that insulin-like growth factor (IGF)-Ⅱ is a growth factor and its signaling pathway so as to develop a molecular therapy for hepatoblastoma. METHODS: Huh-6 and HepG2, human hepatoblastoma cell lines, were used. IGF-Ⅱ was added to the medium deprived of serum. Western blot analysis was performed to clarify the expression of IGF-Ⅰ receptor (IGF-IR). Inhibitors of IGF-IR (piclopodophyllin, PPP), phosphatidyl-inositol (PI) 3-kinase (LY294002 and Wortmannin), or mitogen-activated protein (MAP) kinase (PD98059) were added to unveil the signaling pathway of IGF-Ⅱ. Cells were analyzed morphologically with hematoxylin-eosin staining to reveal the mechanism of suppression of cell proliferation. RESULTS: IGF-Ⅱ stimulated cells proliferated to 2.7 (269% ± 76%) (mean ± SD) (Huh-6) and 2.1 (211% ± 85%) times (HepG2). IGF-IR was expressed in Huh-6 and HepG2. PPP suppressed the cell number to 44% ± 11% (Huh-6) and 39% ± 5% (HepG2). LY294002 and Wortmannin suppressed the cell number to 30% ± 5% (Huh-6), 44% ± 0.4% (HepG2), 49% ± 1.0% (Huh-6) and 46% ± 1.1% (HepG2), respectively. PD98059 suppressed the cell number to 33% ± 11% for HepG2 but not for Huh-6. When cell proliferation was prohibited, many Huh-6 and HepG2 cells were dead with pyknotic or fragmented nuclei, suggesting apoptosis. CONCLUSION: IGF- Ⅱ was shown to be a growth factor of hepatoblastoma via IGF-Ⅰ receptor and PI3 kinase which were good candidates for target of molecular therapy.
基金Supported by A Grant-in-Aid from the Ministry of HealthLabour and Welfare of Japan+2 种基金No.KHD1017by that from JSTPRESTO
文摘AIM: To identify kinases involved in phenotype regulation of vascular endothelial cells(VECs): Proproliferative G-protein signaling 5(RGS5)^(high)(typeⅠ) vs anti-proliferative RGS5^(low)(typeⅡ) VECs.METHODS: Proteomic kinase assays were performed to identify the crucial kinase involved in the phenotype regulation of human VECs using typeⅠ VECs, which promotes the proliferation of human vascular smooth muscle cells(VSMCs), and typeⅡ VECs, which suppress the proliferation of human VSMCs. The assays were performed using multiple pairs of typeⅠ and typeⅡ VECs to obtain the least number of candidates. The involvement of the candidate kinases was verified by evaluating the effects of their specific inhibitors on the phenotype regulation of human VECs as well as the expression levels of regulator of RGS5, which is the causative gene for the "typeⅡ to typeⅠ" phenotype conversion of human VECs. RESULTS: p38α mitogen-activated protein kinase(p38α MAPK) was the only kinase that showed distinctive activities between typeⅠ and typeⅡ VECs: p38α MAPK activities were low and high in type-Ⅰand typeⅡ VECs, respectively. We found that an enforced expression of RGS5 indeed lowered p38α MAPK activitiesin typeⅡ VECs. Furthermore, treatments with a p38α MAPK inhibitor nullified the anti-proliferative potential in typeⅡ VECs. Interestingly, MAPK inhibitor treatments enhanced the induction of RGS5 gene. Thus, there is a vicious cycle between "RGS5 induction" and "p38α MAPK inhibition", which can explain the unidirectional process in the stress-induced "typeⅡ to typeⅠ" conversions of human VECs. To understand the upstream signaling of RGS5, which is known as an inhibitory molecule against the G protein-coupled receptor(GPCR)-mediated signaling, we examined the effects of RGS5 overexpression on the signaling events from sphingosine-1-phosphate(S1P) to N-cadherin, because S1 P receptors belong to the GPCR family gene and N-cadherin, one of their downstream effectors, is reportedly involved in the regulation of VEC-VSMC interactions. We found that RGS5 specifically bound with S1P1. Moreover, N-cadherin localization at intercellular junctions in typeⅡ VECs was abolished by "RGS5 overexpression" and "p38α MAPK inhibition".CONCLUSION: p38α MAPK plays crucial roles in "type-Ⅰ vs type-Ⅱ" phenotype regulations of human VECs at the downstream of RGS5.
基金the State "863" High-Tech R&D Project (Grant No. 863-102-11-03-04).
文摘The recently developed yeast three-hybrid system is a powerful tool for analyzing RNA-protein interactions in vivo. However, large numbers of false positives are frequently met due to bait RNA-independent activation of the reporter gene in the library screening using this system. In this report, we coupled the colony color assay with the 5FOA (5-fluoroorotic acid) negative selection in the library screening, and found that this coupled method effectively eliminated bait RNA-independent false positives and hence greatly improved library screening efficiency. We used this method successfully in isolation of cDNA of an RNA-binding protein that might play important roles in certain cellular process. This improvement will facilitate the use of the yeast three-hybrid system in analyzing RNA-protein interaction.
基金ThisworkwassupportedbytheNationalOutstandingYouthFoundationofChina (No.39725025)andtheNaturalScienceFoundationofGuangdongProvince (No .K 160 )
文摘OBJECTIVES: To study the concentration, distribution and expression of IL-5 in nasal polyp tissues and explore its significance in micro-environment differentiation of eosinophil accumulation. METHODS: The concentration and expression of IL-5 in nasal polyp tissues of 40 patients were determined by ELISA and immunohistochemistry and inferior turbinate mucosa from patients with nasal polyps and healthy volunteers were used as control. RESULTS: IL-5 concentration in polyp tissues was significantly higher than that in turbinate mucosa (P 0.05). IL-5 concentrations in polyp tissues were markedly higher in patients with allergic rhinitis compared with those without (P 0.05). 80.1% of the eosinophils were positive for IL-5 and 90.9% of IL-5 positive cells were eosinophils. Only 3.7% of lymphocytes and neutrophils were positive for IL-5; IL-5 was not detectable in epithelial cells. IL-5 expression in eosinophils of polyp tissues was remarkably stronger than that of the turbinate mucosa (P 0.05). IL-5 expression of eosinophils in polyp tissue was significantly stronger in patients with allergic rhinitis compared with those without (P 0.05). CONCLUSION: IL-5 is the key cytokine in eosinophilic pathologic mechanisms in nasal polyp tissues.
基金financially supported by the National Natural Science Foundation of China(Nos.22236002 and 21925402)this work is also financially supported by National Key R&D Program(No.2021YFA1200300).
文摘Paclitaxel(PTX),methotrexate(MTX),and 5-fluorouracil(5-FU)are commonly-used small molecule anti-tumor drugs for breast cancer.Unfortunately,drug resistance occurs with long-term treatment or excessive use,and the high concentrations of PTX,MTX,and 5-FU in patients may lead to side effects with dose-limiting toxicities,such as myelosuppression,hepatotoxicity,and peripheral neuropathy.Therefore,concentration monitoring of PTX,MTX,and 5-FU in clinical treatment is very important.We prepared highly sensitive and specific monoclonal antibodies using several haptens,and established a multiple paper-based sensor utilizing optical signals of gold nanoparticles,which simultaneously detected PTX,MTX,and 5-FU in human plasma or urine with 10 min.A portable scanner for quantitative detection in plasma and urine samples was used,and the calculated limit of detection(cLOD)values were 0.002 and 0.142μg/mL for PTX,0.187 and 0.976 ng/mL for MTX,and 0.057 and 0.128μg/mL for 5-FU,respectively.In the recovery test,the recovery rates and the coefficient of variation were 85.84%–108.81%and 1.23%–8.80%,respectively,indicating the reliability and accuracy of the multiple gold immunochromatographic strip(GIS).In addition,for the determination of collected clinical plasma samples,the correlation between the test data of the multiple GIS and liquid chromatography–tandem mass spectrometry(LC–MS/MS)was good.Therefore,the developed multiple GIS could be applied to the rapid detection of PTX,MTX,and 5-FU in different clinical samples.
文摘OBJECTIVE: To screen the 5' regulatory region of the aldose reductase (AR) gene for genetic variabilities causing changes in protein expression and affecting the promoter function. METHODS: The screenings were carried out by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). All SSCP variants were submitted for DNA sequencing and inserted into the plasmid chloromycetin acetyl transferase (CAT) enhancer vector. The constructs were used to transfect Hela cells, and CAT assays were performed to assess promoter activity. Gel mobility shift and footprinting assays were also performed to determine the interaction between the DNA and nuclear proteins. RESULTS: Two polymorphisms, C (-106) T and C (-12) G, were identified in the regulatory region in 123 Chinese control subjects and 145 patients with type 2 diabetes mellitus. The frequencies of genotypes WT/WT, WT/C (-12) G and WT/C (-106) T were not significantly different between the subjects and patients. In the patients with and without retinopathy, frequencies of WT/C (-106) T were 31.5% and 17.5% (P 0.05) respectively. The total frequency of WT/C (-12) G and WT/C (-106) T in patients with retinopathy was 41.8%, significantly higher than that (20.0%) in patients without retinopathy (P
文摘New series of pyrazolo[1,5-α]pyrimidine derivatives 7a-i,11a-c and Schiff bases 13a-c were synthesized and screened for their in vitro antitumor activity against three human carcinoma cell lines,namely colorectal carcinoma(HCT116),prostate adenocarcinoma(PC-3) and liver carcinoma(HepG-2) using MTT cytotoxicity assay at 100 μg/mL.Some of the tested compounds displayed good anticancer activities against HCT-116 and PC-3 cells.Whereas,compounds 7d and 11 a showed better antitumor activity than the rest of the compounds against both cell lines.A structure-activity relationship(SAR) has been discussed and structures of the newly synthesized compounds were confirmed by different spectral data(MS,IR,^1H NMR and ^13C NMR) and elemental analysis.
文摘Objective:To investigate the anticancer activity of the total flavonoids isolated from a herbal formula,Xianhe Yanling Recipe(仙鹤延龄方),a recipe commonly used in cancer patients in China.Methods: The in vitro anticancer activity of the total flavonoids was determined using the 3-(4,5-dimethylthiazole-2-yl)-2,5- diphenyltetrazolium bromide(MTT) assay on three cancer cell lines:MCF-7(a human breast adenocarcinoma cell line),HepG-2(a human hepatocellular carcinoma cell line) and ES-2(a human ovarian cancer cell line). The in vivo anticancer effect of the total flavonoids was assessed in a mouse tumor model bearing H22-induced hepatocellular carcinoma,and cisplatin was used as a positive control.Results:The total flavonoids exerted a powerful inhibitory effect on the three cell lines,with 50%inhibiting concentrations(IC_(50)) of 24.948,31.569 and 6.923μg/mL,respectively.In vivo studies showed that the total flavonoids had dose-dependent inhibitory effects on hepatocellular carcinoma in mice.Conclusion:The total flavonoids from Xianhe Yanling Recipe have potential anticancer activity,and further researches and development are warranted.
基金This work was supported by the National Ninth Five-Year Plan High Technology Projects (Grant No. 96-C02-01-09).
文摘Neuronal growth inhibitory factor (GIF), named Metallothioneins-III (MT-III), is the first protein validated to be capable of inhibiting the growth of neurons in nervous system. We have detected the effects of recombinant GIF on the growth of neuroblastoma SY5Y and pheochro-mocytoma PC12 by the MTT (Thiazolyl blue) reduction as-say. Recombinant GIF inhibited PC12 in vitro; the inhibitory rate was about 25% when GIF was at 100 mg/L; and the inhibitory rate was about 50% when GIF was at 300 mg/L. It is shown that PC12 could serve as a proper model for de-tecting neuronal growth inhibitory activity of GIF. Recom-binant GIF did not inhibit neuroblastoma SY5Y in vitro, a common model of neuroma; it is also shown that GIF could not inhibit neuromata extensively. The reason for GIF inhib-iting PC12 may be that PC12 have some properties of cho-linergic neuron. It must play an important role in discover-ing the mechanism of GIF’s neuronal growth inhibitory ac-tivity.