Detection of Survivin mRNA in nasopharyngeal carcinoma by real-time fluorescence quantitative RT-PCR

Objective： To establish the method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in nasopharyngeat carcinoma （NPC） tissues. Methods： The total RNA was extracted from NPC cell line CNE-2 and tissues with Trizol and then been transcribed reversely to cDNA, a method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in NPC tissues had been established, in which chronic nasopharyn-gitis patients＇ nasopharynx tissues treated as control group. Results： The expression of Survivin mRNA all could be detected either in CNE-2 cells, NPC tissues or in chronic nasopharyngitis patients＇ nasopharynx tissues, and there was higher the expression level of Survivin mRNA in NPC tissues than which in chronic nasopharyngitis patients＇ nasopharynx tissues, the difference was significant （P 〈 0.01）. The expression of Survivin mRNA could be detected both in stage Ⅰ ＋ Ⅱ and stage Ⅲ ＋ Ⅳ NPC, and there was no significant difference in relative quantifications of gene expression between these two groups （P 〉 0.05）. There was no relationship between Survivin mRNA expression and age and sex of NPC patients （P 〉 0.05）. Conclusion： Real time fluorescence quantitative RT-PCR is a rapid, effective and high sensitive method for detecting the expression of Survivin mRNA in NPC tissues. The overexpression of Survivin mRNA may play some roles in pathogenesis of NPC.

Detection and clinical significance of multidrug resistance-1 mRNA in bone marrow cells in children with acute lymphoblastic leukemia by real-time fluorescence quantitative RT-PCR

Objective： Multidrug resistance（MDR） is one of the most important reasons for treatment failure and recurrence of acute leukemia. Its manifestations are different in children with acute lymphoblastic leukemia（ALL） which may be due to different detection methods. This study was to detect the expression of MDR1 mRNA in bone marrow cells of children with ALL by real-time fluorescence- quantitative reverse transcription polymerase-chain reaction（FQ-RT-PCR）, and combine minimal residual desease（MRD） detection by flow cytometry（FCM） and to study their relationship with treatment response and prognosis of ALL. Methods：The MDR1 mRNA levels in bone marrow cells from 67 children with ALL[28 had newly diagnosed disease, 27 had achieved complete remission（CR）, 12 recurrent] and 22 children without leukemia were detected by FQ-RT-PCR. MRD was detected by FCM. The patients were observed for 9-101 months, with a median of 64 months. Results：Standard curves of human MDR1 and GAPDH genes were constructed successfully. MDR1 mRNA was detected in all children with a positive rate of 100%. The mRNA level of MDR1 was similar among the newly diagnosed ALL group, CR group, and control group（P 〉 0.05）, but significantly higher in the recurrence group than that in newly diagnosed disease group and control group（0.50 ± 0.55 vs. 0.09 ± 0.26 and 0.12 ± 0.23, P〈 0.05）. 54 ALL patients were followed up, and it was found that MDR1 mRNA level was significantly higher in ALL patients within 3 years duration than that of ALL patients with 3-6 years and over 6 years duration（0.63 ± 0.56 vs. 0.11 ± 0.12 and 0.04 ± 0.06, P〈 0.01）. For the 28 children with newly diagnosed disease, the MDR1 mRNA level was similar between WBC 〉 50 ~ 109 group and WBC〈50 × 10^9 group（P〉 0.05）. In the 33 CR patients, the MDR1 mRNA level was significantly higher in MRD〉10a group than that in MRD〈10a group（0.39 ± 0.47 vs. 0.03 ± 0.03, P 〈 0.05）. Conclusion：The sensitivity and specificity of FQ-RT-PCR in detecting MDR1 mRNA in bone marrowy cells of children with ALL patients are high. MDR1 mRNA is expressed in children with and without leukemia. MDR1 mRNA is highly expressed in the CR ALL patients with high MRD, recurrence and short duration（within 3 years）. Monitoring MRD and the MDR1 mRNA level might be helpful for individual treatment.

Synchronous Detection of DNA/RNA of Four Shrimp Viruses by Real-time Fluorescence Quantitative RT-PCR

[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel real-time fluorescence quantitative RT-PCR assay was established and optimized for simultaneously detecting DNA/RNA of four shrimp viruses （WSSV, IHHNV, TSV and YHV ）. [ Result] The optimized real-time fluorescence quantitative RT-PCR system gener- ated typical amplification curves with high amplification efficiencies （E = 1.06, 1.07, 0.92 and 0.92, respectively）, good hnear relationship （ r = 1 ）, uniform repeatability （ standard deviation = 0.05 - 0.46 ; variation coefficient = 0.26% - 1.62% ） and high sensitivity, exhibiting no significant differences compared with re- al-time fluorescence quantitative PCR （average error of Ct value = 0.04 -0.40; T = 0.53 -2.50; P 〉 0.05 ）. The total detection time was about 1 h. [ Conclusion] The optimized real-time fluorescence quantitative RT-PCR system can be used for rapid detection of WSSV, IHHNV, TSV and YHV.

TaqMan real-time fluorescent quantitative RT-PCR in detection of macrophage inflammatory protein-2γ mRNA in myocarditis murine

Objective: To study the role of macrophage inflammatory protein (MIP)-2γ in myocarditis pathogenesis in BALB/c mice. Methods: The relationship between the progression of Coxsarckie virus B3(CVB3) viral myocarditis and experimental autoimmune myocarditis and MIP-2γ mRNA expression in mouse was studied by TaqMan real-time fluorescent quantitative RT-PCR. Results: MIP-2γ mRNA expression rose on 3 to 5 d after CVB3 infection, reached peak on 7 d, and returned to normal level until 14 d, which corresponded well with the disease course. The MIP-2γ mRNA expression level rose significantly on the day 18 d after immunization with porcine cardiac myosin, which was consistent with pathological examination. Conclusion: MIP-2γ may be involved in the pathogenesis of myocarditis.

The quantitative expressions of lymphangiogenic factors and metastasis in human colorectal cancers

Objective： The purpose of this paper was to study the expression levels of newly described lymphatic endothelial markers – LYVE-1, Prox-1, podoplanin and 5’-nucleotidase, and their correlation with metastasis of human colorectal cancers. Methods： Tumor and corresponding tumor-side normal tissue samples were obtained from resected specimens immediately after operation. Expression level of each factor was determined by quantitative real-time PCR （RT-PCR） and Western blot technique. Results： Expression levels of lymphatic endothelial markers LYVE-1, Prox-1, podoplanin and 5’-nucleotidase were significantly different in tumor and tumor-side normal groups. Expression levels of Prox-1 and podoplanin were higher in patients with positive lymph node metastasis than those without metastasis. LYVE-1, but not 5’-nucleotidase expression level was higher in both cancer and normal groups. Conclusion： These results indicate that combined quantitative analysis of lymphangiogenic markers LYVE-1, Prox-1 and podoplanin in colorectal cancer specimens may be useful in predicting metastasis of colorectal cancer to regional lymph nodes. However, the role of 5’-nucleotidase in predicting metastasis of colorectal cancer still remains to be further analyzed.

Quantitative analysis of a panel of gene expression in prostate cancer——with emphasis on NPY expression analysis

Objective： To investigate molecular alterations associating with prostate carcinoma progression and potentially provide information toward more accurate prognosis/diagnosis. Methods： A set of laser captured microdissected （LCM） specimens from 300 prostate cancer （PCa） patients undergoing radical prostatectomy （RP） were defined. Ten patients representing ＂aggressive＂ PCa, and 10 representing ＂non-aggressive＂ PCa were selected based on prostate-specific antigen （PSA） recurrence, Gleason score, pathological stage and tumor cell differentiation, with matched patient age and race between the two groups. Normal and neoplastic prostate epithelial cells were collected with LCM from frozen tissue slides obtained from the RP specimens. The expressions of a panel of genes, including NPY, PTEN, AR, AMACR, DD3, and GSTP1, were measured by quantitative real-time RT-PCR （TaqMan）, and correlation was analyzed with clinicopathological features. Results： The expressions of AMACR and DD3 were consistently up-regulated in cancer cells compared to benign prostate epithelial cells in all PCa patients, whereas GSTP1 expression was down regulated in each patient. NPY, PTEN and AR exhibited a striking difference in their expression patterns between aggressive and non-aggressive PCas （P=0.0203, 0.0284, and 0.0378, respectively, Wilcoxon rank sum test）. The lower expression of NPY showed association with ＂aggressive＂ PCas based on a larger PCa patient cohort analysis （P=0.0037, univariate generalized linear model （GLM） analysis）. Conclusion： Despite widely noted heterogeneous nature of PCa, gene expression alterations ofAM,4CR, DD3, and GSTP1 in LCM-derived PCa epithelial cells suggest for common underlying mechanisms in the initiation of PCa. Lower NPY expression level is significantly associated with more aggressive clinical behavior of PCa; PTEN and AR may have potential in defining PCa with aggressive clinical behavior. Studies along these lines have potential to define PCa-associated gene expression alterations and likely co-regulation of genes/pathways critical in the biology of PCa onset/progression.

Detecting PML-RARα transcript in acute promyelocytic leukemia using real-time quantitative RT-PCR

Background Real-time quantitative RT-PCR （RQ-PCR） assay has become a vital tool to monitor residual disease of leukemia, However, the complexity and standardization of RQ-PCR should never be overlooked and the results should be interpreted cautiously in clinical conditions. We aimed to assess the methodology of RQ-PCR and its clinical applications in monitoring molecular kinetics of 36 newly diagnosed cases of acute promyelocytic leukemia patients with t （15;17） from October 2004 to December 2005.Methods All the TaqMan probe-based RQ-PCR reactions and analysis were performed on an ABI-PRISM 7500 platform, The quantitation of PML-RARα transcripts was represented by the normalized quotient, that is, PML-RARα transcript copies divided by ABL transcript copies, According to induction therapy, the patients were classed into two groups： group 1 （n=23）, three-drug combination including arsenics, all-trans retinoic acid and mitoxantrone; and group 2 （n=13）.two-drug combination from all-trans retinoic acid, arsenics and mitoxantrone.Results The sensitivity of RQ-PCR was 1 per 105 cells and 5 copies of the PML-RARα transcript could be reproducibly detected, No false positive results occurred in 40 non-acute promyelocytic leukemia samples, Optimal amplification efficiency could be attained, which was determined by the slope of the standard curves （slope： -3.2 -- -3.7）. The inter-assay and intra-assay variation coefficients of the method were 1.01% and 0.56% respectively. Although the time to attain hematological complete remission was similar in both groups, the time to achieve molecular remission of group 1 was significantly shorter than that of group 2 （61 days vs 75 days, P=0.034）. The rate of molecular remission within 70 days was higher in group 1 than in group 2 （75.00% vs 38.46%, P=0.036）, Compared with pretreatment, median reduction of the PML-RARα transcript before first consolidation therapy differed significantly between group 1 and group 2 （log scale, 3.15 vs 2.31, P=0.024）, Interestingly, we found that PML-RARα transcript levels temporarily increased in bone marrow （7 patients） and peripheral blood （22 patients） samples of patients during induction therapy in both groups.Conclusions The RQ-PCR assay is reliable for the detection of PML-RARα transcripts. Arsenics, all-trans retinoic acid and mitoxantrone triad induction treatment of acute promyelocytic leukemia is superior to two-drug combination induction therapy in terms of the molecular response.

Selection of reference genes for qRT-PCR analysis of gene expression in sea cucumber Apostichopus japonicus during aestivation

Quantitative real-time reverse transcription-polymerase chain reaction （qRT-PCR） is a technique that is widely used for gene expression analysis, and its accuracy depends on the expression stability of the internal reference genes used as normalization factors. However, many applications of qRT-PCR used housekeeping genes as internal controls without validation. In this study, the expression stability of eight candidate reference genes in three tissues （intestine, respiratory tree, and muscle） of the sea cucumber Apostichopus japonicus was assessed during normal growth and aestivation using the geNorm, NormFinder, delta CT, and RefFinder algorithms. The results indicate that the reference genes exhibited significantly different expression patterns among the three tissues during aestivation. In general, the β-tubulin （TUBB） gene was relatively stable in the intestine and respiratory tree tissues. The optimal reference gene combination for intestine was 40S ribosomal protein S18 （RPSI 8）, TUBB, and NADH dehydrogenase （NADH）; for respiratory tree, it was β-actin （ACTB）, TUBB, and succinate dehydrogenase cytochrome B small subunit （SDHC）; and for muscle it was α-tubulin （TUBA） and NADH dehydrogenase [ubiquinone] 1α subcomplex subunit 13 （NDUFA13）. These combinations of internal control genes should be considered for use in further studies of gene expression in A.japonicus during aestivation.

Establishment and Application of Digital RT-PCR Assay for Detection of Avian Influenza Virus H9 Subtype

A digital RT-PCR method for rapid detection of H9 subtype influenza was established by comparing the two methods of digital RT-PCR and real-time quantitative RT-PCR. The sensitivity, specificity and reproducibility of the two methods for H9 were determined by gradient dilution using the same pair of primers and probes. Both methods were able to detect 104 times diluted H9 pathogens, while digital RT-PCR could detect H9 in single droplets, and its sensitivity was higher than real-time quantitative RT-PCR. At the same time, the specificities of both methods were very strong, with no amplification reactions for H3N2, H4N2, H6N2. The reproducibility of the two methods were also good. Digital RT-PCR has a higher sensitivity than real-time quantitative RT-PCR and could play an important role in the rapid detection of H9 subtype influenza virus.

Liquid biopsy for non-invasive assessment of liver injury in hepatitis B patients

BACKGROUND Hepatitis B is a major public health problem in China. Accurate liver injury assessment is essential for clinical evidence-based treatment. Liver biopsy is considered the gold standard method to stage liver disease, but it is not widely used in resource-limited settings. Therefore, non-invasive liquid biopsy tests are needed. AIM To assess liver injury in hepatitis B patients using quantified cell free DNA combined with other serum biomarker as a liquid biopsy-based method. METHODS A cohort of 663 subjects including 313 hepatitis B patients and 350 healthy controls were enrolled. Ultrasound-guided liver biopsies followed by histopathological assessments were performed for the 263 chronic hepatitis B patients to determine the degree of liver injury. Cell-free DNA was quantified using a novel duplex real-time polymerase chain reaction assay. RESULTS Compared with healthy controls, patients with hepatitis B virus (HBV) infection had significantly higher plasma DNA, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, and HBV DNA levels (P<0.01). Serum ALT, AST, bilirubin, and plasma DNA levels of patients with markedsevere inflammation were significantly higher than those with mild-moderate inflammation (P<0.01). There was a statistically significant correlation between hepatocyte inflammation severity and serum bilirubin (R^2=0.673, P<0.01) or plasma DNA (R^2=0.597, P<0.01) levels. The areas under the curves of serum ALT, bilirubin, plasma DNA, and their combination to distinguish between patients with mild–moderate and marked-severe inflammation were 0.8059, 0.7910, 0.7921, and 0.9564, respectively. CONCLUSION The combination of plasma DNA, serum ALT, and bilirubin could be a candidate liquid biopsy for non-invasive assessment of liver injury in hepatitis B patients.

Study on the Expression Laws and Regulatory Functions of miRNA-181b in the Anterior Pituitary of Cattle

[Objective] The research aimed to discuss the differential expression quantity of miRNA-181b in mature（18-month-old） and immature（one-month-old） cattle＇s anterior pituitary and its regulation function.[Method] cDNA library of miRNA in mature（18-month-old） and immature（one-month-old） cattle＇s anterior pituitary were established.After Solexa high-throughput sequencing of miRNA in the cDNA library,miRNA in anterior pituitary of bulls was identified.miRNA-181b with differential expression were selected from the sequencing results.By real-time quantitative RT-PCR,the expression laws of miRNA-181b in the anterior pituitary of Yanbian Cattle in different growth period was validated.And the target genes of miRNA-181b were forecast by using TargetScanS prediction software.[Result] The expression quantity of miRNA-181b had great difference in cattle＇s anterior pituitary different growth periods.The expression quantity of miRNA-181b in anterior pituitary of one-month-old cattle was 4.05 times as that in 18-month-old cattle.The binding of miRNA-181b with 838-844 bases in 3＇ untranslated region of FSHβ gene was specific and the binding base sites were UGAAUGUA.[Conclusion] This research provided the theoretical basis for the transcription regulation research of FSHβ.

Effects of p,p'-DDE exposure on gonadal development and gene expression in Japanese medaka(Oryzias latipes)

Although 1,1-dichloro-2,2-bis（p-chlorophenyl）-ethylene （p,p′-DDE）, the major and most persistent metabolite of dichlorodiphenyltrichloroethane （DDT）, was continually detected in wild fishes that showed abnormal gonad development such as intersex, little is known about the impact of p,p′-DDE exposure on gonad development in fishes. To survey the effects of p,p′-DDE on gonadal development and gene expressions, male juvenile （20-d post hatch） Japanese medaka （Oryzias latipes） was exposed to 1, 5, 20, and 100 μg/L p,p′-DDE for two months. Increased hepatosomatic index （HSI） and decreased gonadosomatic index （GSI） were found in the p,p′-DDE-treated groups. Intersex was found in 100 μg/L p,p′-DDE exposure group, as well as 100 ng/L 17α-ethynylestradiol （EE2） group. By quantitative real-time RT-PCR, it was found that gene expressions of vitellogenins （VTG-1, VTG-2）, choriogenins （CHG-H, CHG-L）, and estrogen receptor α （ER-α） in the liver of the fish were significantly up-regulated by p,p′-DDE exposure. VTG-1 and VTG- 2 were recommended as the preferred biomarker for assessing anti-androgenic p,p′-DDE because they were the highest up-regulated among the genes and showed good dose-response relationship. The up-regulated ER-α suggested that a potential synergetic effect would occur when p,p′-DDE coexists with other ER-α-binding endocrine-disrupting chemicals （EDCs）.

Down-Regulated Expression of RACK1 Gene by RNA Interference Enhances Drought Tolerance in Rice

The receptor for activated C-kinase 1 （RACK1） is a highly conserved scaffold protein with versatile functions, and plays important roles in the regulation of plant growth and development. Transgenic rice plants, in which the expression of RACK1 gene was inhibited by RNA interference （RNAi）, were studied to elucidate the possible functions of RACK1 in responses to drought stress in rice. Real-time PCR analysis showed that the expression of RACK1 in transgenic rice plants was inhibited by more than 50%. The tolerance to drought stress of the transgenic rice plants was higher as compared with the non-transgenic rice plants. The peroxidation of membrane and the production of malondialdehyde were significantly lower and the superoxide dismutase activity in transgenic rice plants was significantly higher than those in non-trangenic rice plants It is suggested that RACK1 negatively regulated the redox system-related tolerance to drought stress of rice plants.

Detection and quantification of enteroviruses in coastal seawaters from Bohai Bay,Tianjin,China

An 8-month survey was conducted to detect and quantify enteroviruses in Tianjin coastal seawaters of Bohai Bay to assess coastal water quality. Ten water samples were collected from Bohai Bay for the detection and quantification of enteroviruses by conventional reverse transcription polymerase chain reaction （RT-PCR） and SYBR Green real-time quantitative RT-PCR （qRT-PCR）. Total viral nucleic acid was extracted from 500 mL of seawater samples concentrated by Centricon plus-70 centrifugal filter devices. The viral recovery rate was 29.1% based on viral seeding study. The centrifugal ultrafiltration method applied is effective for viral recovery from small volume of polluted water, which may have broader applications to monitoring human virus in aquatic environment. Our results indicated that there was a severe viral contamination in seawater of Bohai Bay. Enteroviruses were detected at concentrations ranging from 1.7 × 10^6 to 6.3 × 10^7 copies/L by qRT-PCR. Sequencing analyses identified that all of the twenty clones as poliovirus type 2. This is the first quantitative report of human viruses in coastal waters of a metropolitan city in China. This study emphasized the importance for the local and central governmertts to monitor and assess the water quality.

Spontaneous Proliferation in Organotypic Cultures of Mouse Cochleae

Cells in mammalian cochleae virtually stop proliferation and exit cellular circle before birth. Consequently, hair cells and spiral ganglion neurons destroyed by ototoxic factors cannot be replaced through proliferative regeneration. However, substantial proliferation occurs in organotypic cultures of cochleae from postnatal mice. In the present study, we studied the time course of proliferative growth in cultures of mouse cochlea explants obtained from up to 12 postnatal days. The mitotic nature of this growth was confirmed by bromodeoxyuridine (BrdU) staining and expression of proliferation cell nuclear antigen (PCNA) evaluated with real-time quantitative poly-merase chain reaction(RT-PCR). Similar growth time course was found in the cochlear explants of different postnatal ages. The new growth reached its maximum at around 2 days in culture followed by a slow-down, and virtually stopped after 5 days of culture. The possible mechanisms and the significance of this proliferation are discussed.

Gene Cloning and Tissue-Specific Expression of G Protein β Subunit in Microplitis mediator (Hymenoptera: Braconidae)

A gene encoding a novel G protein β subunit of β1 subclass, GβMmed was isolated from Microplitis mediator （Hymenoptera： Braconidae）. The full-length sequence of GβMmed is 1 119 bp, the cDNA contains a 1 023 bp open reading frame that encodes a protein with 340 amino acids, and the predicted molecular weight of GβMmed is 37.23 kDa and isoelectric point is 5.86. By the quantitative real-time RT-PCR method, the tissue-specific expression and quantitative changes in the developmental expression profile of GβMmed were detected. It was found that GβMmed was abundantly expressed in M. mediator antennae, head （without antennae）, thorax, abdomen, legs and the wings, and especially at high levels in abdomen. In antennae, expression varied through 1st day before emergence to 5-d-old adults, and had equal expression levels detected in females and males in total. In head, GβMmed expresses while initially high in females, and have another peaked in stage 4 and 1st day, in males showed a peak of GβMmed expression prior to emergence and relatively low levels after emergence. In female abdomen GβMmed expression levels have two peaks in stage 1 and the 5th d, but just have one peak in male abdomen in stage 1. In all other tissues expression was low and stable.

Full length cDNA cloning and expression analysis of annexinA2 gene from deer antler tissue

ANXA2（AnnexinA2）, a calcium-dependent phospholipid bind- ing protein, is involved in various Ca2＋-related biological activities. In the present study, full-length cDNA of ANXA2 was isolated from the velvet antler tip tissue of sika deer （Cervus nippon hortulomm）; the amino acid sequence and gene expression was analyzed by using bioinformatics and real-time reverse transcdptase polymerase chain reaction （RT-PCR） techniques. Nucleotide sequence analysis reveals that the full-length cDNA of the ANXA2 gene was 1372 bp, of which 1020 bp was in the opan-reading frame （OR.F） encoding 339 amino acids; its relative mo- lecular weight was 38.3 kDa; and isoelectrie point was 6.72. Sequence analysis indicates that the protein includes four conserved tan- dem-duplication ANX domains. The gene-aceession nucleotide sequence number in GenBank is JX315571. Expression analysis by RT-PCR re- veals that ANXA2 gene expression has a significant positive correlation with the antler-tissue mineralization process, indicating that this gene may play an important role in the regulation of antler-tissue mineraliza- tion.

Effects of brain-derived neurotrophic factor on induced differentiation of SH-SY5Y cells in vitro

BACKGROUND： Previous studies have demonstrated that brain-derived neurotrophic factor （BDNF） promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly correlates to neural proliferation and apoptosis, remain poorly understood. OBJECTIVE： To investigate the effects of various concentrations of BDNF on cycle-related protein mRNA expression in induce-differentiated SH-SY5Y cells in vitro prior to and following G2 phase, and to analyze the neuroprotective effects of BDNF. DESIGN, TIME AND SETTING： A comparison, observational study, based on cell biology, was performed at the Department of Biochemistry, Medical College of Tongji University, from March 2005 to October 2006. MATERIALS： SH-SY5Y cells were provided by Shanghai Institute of Cytology, Chinese Academy of Science; BDNF by Alomone Labs, Israel; all-trans retinoic acid （ATRA） by Sigma-Aldrich, USA. METHODS： SH-SY5Y cells were randomly divided into three groups： blank control [cells were treated in Insulin-Transferrin-Selenium （ITS） solution for 7 days], ATRA （cells were treated with ITS solution containing 10 μmol/L ATRA for 7 days）, and BDNF （cells were treated identical to the ATRA group for 5 days, and then respectively treated in ITS solution containing 1, 10, and 100 μg/L BDNF for 2 days）. The experiment was repeated three times for each group. MAIN OUTCOME MEASURES： mRNA expression levels of cyclin A1, B1, B2, cyclin-dependent kinase 1, and 5 were detected using quantitative real-time RT-PCR; percentage of cells in G1, S, and G2 phases were detected using fluorescence-activated cell sorting. RESULTS： mRNA expression levels of cyclin A1 in the high-dose BDNF group was significantly less than the ATRA group （P 〈 0.05）.mRNA expression levels of cyclin B1 was significantly less in the different BDNF concentration groups compared with the control and ATRA groups （P 〈 0.05 or P 〈 0.01）. mRNA expression levels of cyclin B2 and cyclin-dependent kinase 1 were significantly decreased in the high-dose BDNF group （P 〈 0.05 or P 〈 0.01）. Cyclin-dependent kinase 5 mRNA expression was significantly greater in the low-dose and moderate-dose BDNF groups compared with the ATRA group （P 〈 0.05）. The percentage of cells in G1 phase was significantly greater in the different BDNF concentration groups compared with the ATRA and control groups （P 〈 0.01）. Moreover, the percentage of cells in S phase was significantly less in the three BDNF groups compared with the ATRA group （P 〈 0.01）. However, the percentage of cells in S phase was significantly less in the low-dose and high-dose BDNF groups compared with the control group （P 〈 0.01）. CONCLUSION： BDNF enhanced the percentage of cells in G1 phase, but did not alter mRNA expression of cell cycle-related proteins prior to or following G2 phase. These results suggested that BDNF was not a risk factor for inducing apoptosis.

Expression of Long Form Leptin Receptor mRNA in Pituitary of Pigs around Puberty

[ Objective] To study the expression of long form leptin receptor （Ob.Rb） mRNA in pituitary of pigs around puberty and explore the rela- tionship between Ob-Rb mRNA and porcine development around pituitary. [Method] Three Sujiang pigs were randomly selected at the age of 120 d, puberty and 180 d, respectively. A pair of primers was designed according to the Ob-Rb sequence published in the GenBank. Total RNAs were extracted from pituitary. The expression of Ob-Rb mRNA was detected by the real-time quantitative RT-PCR. [ Result] The Ob-Rb mRNA was de- tected in pituitaries of pigs at the age of 120 d, puberty and 180 d, respectively. The expression level of Ob-Rb mRNA was lowest at puberty. It was significantly different from that in the 120-day-old pigs and not significantly different from that in the 180-day-old pigs. [ Conclusion] The low expres- sion level of Ob-Rb mRNA is conductive to the arrival of puberty.

The Expression and Clinical Significance of ABCG2, Oct4 and Nanog in Laryngeal Carcinoma

Objective: To investigate the protein expression and clinicopathological characteristics of ABCG2, Oct4, Nanog in laryngeal cancer tissues, and to seek new molecular markers for the diagnosis of laryngeal cancer. Methods: The laryngeal cancer tissues and paracancerous tissues of 87 patients with laryngeal carcinoma diagnosed in the department of otorhinolaryngology and head and neck surgery in our hospital from April 2016 to April 2018 were selected as the subjects. QRT-PCR, Real-time PcR, Western blot and immunohistochemical staining were used to detect the expression of ABCG2, Oct4 and Nanog in (Tumor Tissue) and (Adjacent Tissue) in tumor tissue and paracancerous tissue. Results: The results of RT-PCR showed that the positive rates of ABCG2, Oct4 and Nanog in laryngeal carcinoma tissues were 49.30%, 45.07% and 52.11%, respectively, while those in paracancerous tissues were 22.54%, 21.13% and 15.49%, respectively (P < 0.01). The expression of ABCG2, Oct4 and Nanog in laryngeal carcinoma was correlated with tumor differentiation, depth of invasion, age and sex (P < 0.05), but not with tumor size and TNM stage. Conclusion: The expressions of ABCG2, Oct4 and Nanog in cancer tissues are related to tumor differentiation status, and they can be used as new molecular markers for the diagnosis of laryngeal cancer.