Key genes and regulatory networks for diabetic retinopathy based on hypoxia-related genes:a bioinformatics analysis

AIM:To prevent neovascularization in diabetic retinopathy(DR)patients and partially control disease progression.METHODS:Hypoxia-related differentially expressed genes(DEGs)were identified from the GSE60436 and GSE102485 datasets,followed by gene ontology(GO)functional annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis.Potential candidate drugs were screened using the CMap database.Subsequently,a protein-protein interaction(PPI)network was constructed to identify hypoxia-related hub genes.A nomogram was generated using the rms R package,and the correlation of hub genes was analyzed using the Hmisc R package.The clinical significance of hub genes was validated by comparing their expression levels between disease and normal groups and constructing receiver operating characteristic curve(ROC)curves.Finally,a hypoxia-related miRNA-transcription factor(TF)-Hub gene network was constructed using the NetworkAnalyst online tool.RESULTS:Totally 48 hypoxia-related DEGs and screened 10 potential candidate drugs with interaction relationships to upregulated hypoxia-related genes were identified,such as ruxolitinib,meprylcaine,and deferiprone.In addition,8 hub genes were also identified:glycogen phosphorylase muscle associated(PYGM),glyceraldehyde-3-phosphate dehydrogenase spermatogenic(GAPDHS),enolase 3(ENO3),aldolase fructose-bisphosphate C(ALDOC),phosphoglucomutase 2(PGM2),enolase 2(ENO2),phosphoglycerate mutase 2(PGAM2),and 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3(PFKFB3).Based on hub gene predictions,the miRNA-TF-Hub gene network revealed complex interactions between 163 miRNAs,77 TFs,and hub genes.The results of ROC showed that the except for GAPDHS,the area under curve(AUC)values of the other 7 hub genes were greater than 0.758,indicating their favorable diagnostic performance.CONCLUSION:PYGM,GAPDHS,ENO3,ALDOC,PGM2,ENO2,PGAM2,and PFKFB3 are hub genes in DR,and hypoxia-related hub genes exhibited favorable diagnostic performance.

Analysis of The Correlation Between inhA Gene Mutation and Resistance to Protionamide in Drug-Resistant Mycobacterium Tuberculosis

Objective: To investigate the characteristics of katG and inhA gene mutations in multidrug-resistant tuberculosis (MDR-TB), pre-extensively drug-resistant tuberculosis (preXDR-TB), and their correlation with resistance to protionamide (Pto). Methods: A total of 229 patients with MDR-TB and pre-XDR-TB diagnosed in the Eighth Affiliated Hospital of Xinjiang Medical University from January 2020 to February 2024 were selected to analyze the characteristics of katG and inhA mutations in MTB clinical isolates and their correlation with Pto resistance. Results: The mutation rate of katG (with or without inhA mutation) was 85.2%. The mutation rates in MDR-TB and pre-XDR-TB were 87.4% (125/143) and 81.4% (70/86), respectively. The mutation rate of inhA (including katG mutation) was 14.8% (34/229), which was 12.6% (18/143) and 18.6% (16/86) in MDR-TB and pre-XDR-MTB, respectively. There was no difference in mutation (P > 0.05). Conclusion: The total resistance rate to Pto in 229 strains was 8.7% (20/229), which was 8.4% (12/143) and 9.3% (8/86) in MDR-TB and pre-XDR-TB, respectively. Among the inhA mutant strains, 13 were resistant to the Pto phenotype, and the resistance rate was 65% (13/20). In MDR-TB and pre-XDR-TB strains resistant to Pto, inhA gene mutations occurred in 66.7% (6/9) and 63.6% (7/11), respectively. The resistance rates of MDR-MTB and pre-XDR-TB strains without inhA gene mutation to Pto were 2.4% (3/125) and 5.7% (4/70), respectively.

Mutation Characteristics of inhA and katG Genes in Isoniazid-Resistant Mycobacterium Tuberculosis Patients in Xinjiang

Objective:To analyze the mutation characteristics of inhA and katG genes in isoniazid-resistant Mycobacterium tuberculosis in Xinjiang.Methods:The katG and inhA in 148 strains of isoniazid-resistant Mycobacterium tuberculosis were amplified through fluorescence quantitative PCR,and the amplified products were sequenced and compared.Results:The inhA gene mutation rate of 148 strains of isoniazid-resistant mycobacterium tuberculosis was 13.51%(20/148),among which the inhA gene mutation rate among patients of Han,Uygur,and Kazakh ethnicity were 15.87%,13.21%,and 17.65%,respectively.There was no significant difference in the inhA mutation rate among nationalities(c^(2)=2.897,P>0.05).The mutation rate of the katG gene was 84.46%(125/148),among which the mutation rates of patients of Han,Uyghur,and Kazak ethnicities were 82.54%,84.91%,and 76.47%,respectively.The Hui and other ethnic groups were all affected by the katG gene mutation.There was no significant difference in the mutation rate of the katG gene among different ethnicities(c^(2)=3.772,P>0.05).The mutation rates of the inhA gene in southern Xinjiang,northern Xinjiang,and other provinces were 18.60%,9.28%,and 37.50%,respectively.The mutation rates of the inhA gene in different regions were statistically different(c^(2)=6.381,P<0.05).There was no significant difference in the inhA mutation rate between patients from southern and northern Xinjiang(c^(2)=2.214,P>0.05)and between southern Xinjiang and other provinces(c^(2)=1.424,P>0.05).However,the mutation rate of the inhA gene in patients from other provinces was higher than that in northern Xinjiang(c^(2)=5.539,P<0.05).The mutation rates of the katG gene in southern Xinjiang,northern Xinjiang,and other provinces were 81.40%,87.63%,and 62.50%,respectively.There was no significant difference in the mutation rates of the katG gene among different regions(c^(2)=3.989,P>0.05).Conclusion:katG gene mutation was predominant in isoniazid-resistant tuberculosis patients in Xinjiang Uygur Autonomous Region,and inhA and katG gene mutation were no different among different ethnic groups.

EXPRESSION AND REVERSION OF DRUG RESISTANCE-AND APOPTOSIS-RELATED GENES OF A DDP-RESISTANT LUNG ADENOCARCINOMA CELL LINE

Objective: To investigate the co-expression of drug resistance- and apoptosis-related genes of cisplatin (CDDP)-selected lung adenocarcinoma cell line A 549 DDP for compared to the parental cell line A549, and reverse of drug resistance by antisense s-oligodeoxynucleotides (S-ODNs) of differentially expressed genes. Methods: Sense and antisense S-ODN were transferred into A 549 DDP cells by lipofectin. The expression of drug resistance and apoptosis related genes was examined by RT-PCR, immunocytochemistry and flow cytometry, respectively. Apoptostic cells were identified by DNA electrophoresis and terminal deoxynucleotidyl transferase (TdT)-mediated biotin dUTP nick end-labeling(TUNEL). Drug resistance of tumor cells was detected by a cell viability (MTT) assay. Results: The expression of bcl-2 was positive and that of multidrug resistance-associated protein (MRP) at mRNA and protein level was increased in A 549 DDP compared to A549 cells. MDR1, c-myc and topoisomeras II (TOPO II) were similarly co-expressed in two cell lines. Both cell lines were negative for c-erbB-2 expression. In A 549 DDP cells, the expression of bcl-2 and MRP was significantly inhibited by their respective antisense S-ODNs. Antisense S-ODNs could also decrease significantly drug resistance of A 549 DDP cells to CDDP by promoting cell apoptosis. Conclusion: Both intrinsic and acquired drug resistance were involved in co-expression of multiple MDR-related genes in lung adenocarcinoma. Cooperation of bcl-2 and MRP genes appeared to play an important action to confer the resistance of A 549 DDP cells to CDDP. Their antisense S-ODNs are responsible for the decrease of drug resistance of this cell line by promoting apoptosis.

Bioinformatics screening of breast cancer-related genes and potential drug research

Objective:To search the the differentially expressed genes between breast cell carcinoma tissues and normal tissues by using bioinformatics technology,and the potential therapeutic drugs for breast cancer were identified,which can provide reference for clinical immune targeted therapy and drug therapy of breast cancer in the future.Methods:"Breast cancer"was searched by using Gene Expression Omnibus(GEO),and GSE79586 chip data was downloaded.The differentially expressed genes in the control group and the breast cancer model group were screened by using bio-communication technology and subjected to GO function analysis,KEGG pathway analysis,differential gene characteristic expression analysis and protein-protein interaction network(PPI)analysis,and the analysis results were further visualized.Prognosis analysis,related function prediction and immune infiltration analysis were performed using the GEPIA,GeneMANIA,and Timer2.0 databases,respectively.Finally,the compounds with potential therapeutic effects on breast cancer are identified through Connectivity Map(CMap).Western blotting and real-time PCR(RT-PCR)were used to verify the core genes and potential therapeutic agents with the highest correlation in vitro.Results:A total of 3916 differentially expressed genes including 1786 up-regulated genes and 2130 down-regulated genes were screened.GO analysis showed that the differential genes were mainly involved in the positive regulation of phosphorylation,secretory vesicles,racemase and epimerase activities.KEGG analysis showed that differential genes were involved in systemic lupus erythematosus,alcoholism,sticky spots,amoebic dysentery Ras signal pathways and other disease pathways.The characteristic expression analysis of differential genes showed that MEK inhibitors,HSP90 inhibitors and signal transduction pathway kinase inhibitors were drugs similar to the differential genes.PPI results showed that H2AFJ,TFF1,GATA3,FOXA1,and CDH1 were core genes related to breast cancer.Two core genes of H2AFJ and TFF1 with the highest correlation were further selected for GEPIA analysis.The results of the analysis showed that the mRNA expression levels of H2AFJ and TFF1 in breast cancer cells were significantly higher than those in normal tissues,and there was a significant correlation with the pathological staging,overall survival rate and disease-free survival rate of breast cancer patients.H2AFJ and TFF1 may be potential prognostic biomarkers for survival of breast cancer patients.The functions of differentially expressed H2AFJ and TFF1 are mainly related to hormone receptor binding,epithelial structure maintenance and epigenetic negative regulation of genes,chromatin tissue involved in negative regulation of transcription,etc.The results of immune infiltration showed that the expressions of H2AFJ and TFF1 had a significant correlation with the infiltration of macrophages,neutrophils,monocytes,CD4+T,CD8+T,B lymphocytes and other immune cells.CMap results showed that compounds such as Gefitinib,Alpelisib,Sorafenib,and Sunitinib had potential therapeutic effects on breast cancer.Western blot and RT-PCR results showed that H2AFJ and TFF1 were significantly overexpressed in breast cancer cells.Gefitinib significantly inhibited the expression of H2AFJ and TFF1 in breast cancer cells(P<0.05,P<0.01).Conclusion:In this study,differentially expressed genes between breast cell carcinoma tissues and normal tissues were screened out by bioinformatics means to further identify key genes and compounds with potential therapeutic effects in the onset process of breast cancer and to further verify the effectiveness of the screened drugs on breast cancer through experiments.It will provide reference for clinical research and development of new drugs against breast cancer in the future in order to develop more effective treatment options.

Transduction of Fas gene or Bcl-2 antisense RNA sensitizes cultured drug resistant gastric cancer cells to chemotherapeutic drugs

AIM To compare the expression level of Fas gene and Bcl-2 gene in gastric cancer cells SGC7901 and gastric cancer MDR (multidrug resistant) cells SGC7901/VCR, to transduce Fas cDNA and Bcl-2 antisense nucleic acid into SGC7901/VCR cells respectively, and to observe the expression of two genes in transfectants and non-transfectants as well as their drug sensitivity.METHODS Eukaryotic expression vector pBK-Fas cDNA and pDOR-anti Bcl-2 were constructed and transfected into SGC7901/VCR cells by lipofectamine, respectively. Northern blot and Western blot were used to detect the expression of mRNA and protein in SGC7901/VCR and SGC7901 cells and transfectants, and drug sensitivity of transfectants for VCR, CDDP and 5-FU was analyzed with MTT assay.RESULTS After gene transfection, 80 for Fas and 120 for antisense Bcl-2 drug-resistant clones were selected from 2×105 cells, transfection rate being 0.04% and 0.06%. Two clones of SGC7901 Fas/VCR cells and SGC7901 anti Bcl-2/VCR cells were randomly selected for further incubation. Hybridization results showed that the expression level of Fas mRNA and protein in SGC7901/VCR cells was much lower, but that of Bcl-2 mRNA and protein was higher than that in SGC7901 cells. The expression of Fas mRNA and protein in SGC7901 Fas/VCR cells was higher, and of Bcl-2 mRNA and protein was lower in SGC7901 anti Bcl-2/VCR cells than that in non-transfectants. MTT assay showed that transfectants were more sensitive to VCR, CDDP, 5-FU than non-transfectants.CONCLUSION Bcl-2 gene displayed high expression while Fas gene had low expression in drug resistant gastric cancer cells. Expression of Bcl-2 protein was effectively blocked in SGC7901 anti Bcl-2/VCR cells by gene transfection. In contrast, the expression of Fas mRNA and protein in SGC7901 Fas/VCR cells increased. Fas gene and Bcl-2 antisense nucleic acid transfection sensitized drug resistant gastric cancer cells to chemotherapeutic drugs. These results suggest cell apoptosis plays an important role in the mechanism of MDR, and enhancing apoptosis might reverse MDR.

Applications and developments of gene therapy drug delivery systems for genetic diseases

Genetic diseases seriously threaten human health and have always been one of the refractory conditions facing humanity.Currently,gene therapy drugs such as siRNA,shRNA,antisense oligonucleotide,CRISPR/Cas9 system,plasmid DNA and miRNA have shown great potential in biomedical applications.To avoid the degradation of gene therapy drugs in the body and effectively deliver them to target tissues,cells and organelles,the development of excellent drug delivery vehicles is of utmost importance.Viral vectors are the most widely used delivery vehicles for gene therapy in vivo and in vitro due to their high transfection efficiency and stable transgene expression.With the development of nanotechnology,novel nanocarriers are gradually replacing viral vectors,emerging superior performance.This review mainly illuminates the current widely used gene therapy drugs,summarizes the viral vectors and non-viral vectors that deliver gene therapy drugs,and sums up the application of gene therapy to treat genetic diseases.Additionally,the challenges and opportunities of the field are discussed from the perspective of developing an effective nano-delivery system.

Anticancer Drug Resistance of HeLa Cells Transfected With Rat Glutathione S-transferase pi Gene

To establish a cytologic expressing system of rat glutathione S-transferase pi (GST-pi) cDNA for detecting the resistance of HeLa cells to anticancer drugs. Methods The assessment was made with various anticancer drugs (adriamycin, mitomycin, cisplatinum and vincristine) that showed different cytotoxicities in transfectant HeLa cells with pSV-GT containing rat GST-pi cDNA (HeLa/pSV-GT) or control pSV-neo (HeLa/pSV-neo). Expression levels of GST-pi mRNA in HeLa/pSV-GT and HeLa/pSV-neo were measured by in situ hybridization using Digoxin-labelled cDNA probe. Results HeLa/pSV-GT expressed significantly high degree of GST-pi mRNA, whereas both HeLa/pSV-neo and HeLa cells had very low expression. Cytotoxicities of HeLa/pSV-GT and HeLa/pSV-neo with 4 anticancer drugs were measured by MTT assay. Drug concentrations for yielding 50% inhibition (IC50) in HeLa/pSV-GT by adriamycin, mitomycin and cisplatinum were 70.13 靏/mL, 10.95 靏/mL and 16.52 靏/mL, respectively. In contrast, IC50 in HeLa/pSV-neo was 10.34 靏/mL, 7.48 靏/mL and 13.70 靏/mL, respectively. The cytotoxicities of vincristine on both HeLa/pSV-GT and HeLa/pSV-neo were not significantly different. Conclusions Our findings suggest that HeLa/pSV-GT containing rat GST-pi cDNA is resistant to some anticancer drugs due to overexpression of GST-pi. Also, HeLa/pSV-GT cell line could serve as a useful cytogenetic model for further research.

Clinical Study of Multi-drug Resistance Gene(MDR1) Expression in Primary Ovarian Cancer

This study was designed to measure the multi-drug resistance gene (MDR1) mRNA content and analyze clinical relationship between MDR1 expression and drug resistance in primary ovarian cancer. Reverse transcription PCR (RT-PCR) was used to measure MDR1 mRNA content in biopsy sample of 31 primary ovarian cancers (experimental group) and 30 gynecological tumors (control group). The level of 95.2% (20/21) MDR1 expression was relatively low, and the detected rate of MDR1 expression was 67.7%(21/31) in experimental group,which was higher than that in control group (40.0%, P<0.05). The differences of MDR1 expression between the effective group and no effect group after combined chemotherapy was significant (P<0.05). No significant relationship was found between MDR1 expression and clinical stage or histological classification or grade of differentiation in experimental group. We are led to concluded that primary ovarian cancers have drug-resistance clones which might express MDR1 spontaneously and expression of MDR1 may be used as a prognostic and predictive indicator for clinical response of ovarian cancers to combined chemotherapy.

Drug resistance gene expression and chemotherapy sensitivity detection in Chinese women with different molecular subtypes of breast cancer

Objective:The aim of the study was to identify specific chemosensitivity drugs for various molecular subtypes of breast tumors in Chinese women,by detecting the expression of drug resistance genes and by using the drug sensitivity test on different molecular subtypes of breast cancers.Methods:The expression of drug resistance genes including Topo Ⅱ,GST-π,P-gp,LRP,and CD133 were detected with immunohistochemistry in a tissue microarray.Drug sensitivity tests included those for paclitaxel,epirubicin,carboplatin,vinorelbine,and fluorouracil and were conducted on primary cancer tissue cells and cell lines,including the T47 D,BT-474,and MDA-MB-231 cells and human breast cancer xenografts in nude mice.Results:The different drug resistant genes Topo Ⅱ,GST-π,P-gp,and LRP were differentially expressed among different molecular subtypes of breast cancers(P<0.05).Positive expression of CD133 was highest in basal-like breast cancer(P<0.05).Kaplan-Meier survival analysis showed that positive expressions of Topo Ⅱ and CD133 both correlated with shorter disease-free survival(DFS)(P<0.05)and overall survival(P<0.05),and positive expression of LRP correlated only with shorter DFS(P<0.05).BT-474 showed chemosensitivity to paclitaxel and epirubicin,while MDA-MB-231 showed chemosensitivities to paclitaxel,epirubicin,carboplatin,and fluorouracil(T/C≤50%).The basal-like and HER2+breast cancer primary cells showed chemosensitivities to paclitaxel and epirubicin with significant differences compared with luminal breast cancer primary cells(P<0.05).Conclusions:The differential expression of drug resistance genes and the differential chemosensitivities of drugs in different molecular subtype of breast cancers suggested that individual treatment should be given for each type of breast cancer.

Molecular Characterization and Virulence Genes of Aeromonas hydrophila Isolated from the Chinese Giant Salamander (Andrias davidianus)

The Chinese giant salamander(Andrias davidianus) is the largest living amphibian in the world. Aeromonas hydrophila strain L602 was isolated from A. davidianus. The 16S rDNA gene of this isolate was amplified using PCR,and the phylogenetic tree was constructed by the neighbor-joining method. Four virulence genes(aerA,aha1,hly and alt) of A. hydrophila were amplified by PCR and drug resistances were tested using Kirby-Bauer disk diffusion method. The results showed that the length of this 16S rDNA sequence was 1453 bp,which showed 99% homology with A. hydrophila. The GenBank accession number was JX155398. Phylogenetic analysis indicated it grouped together with A. hydrophila. Four virulence genes were all detected,indicating that strain L602 was highly virulent. This stain was resistant to four antibiotics(vibramycin,furazolidone,ampicillin and erythromycin),while it was insensitive to streptomycin. Furthermore,this strain was susceptible to six antibiotics(sulfafurazole,ciprofloxacin,penbritin,norfloxacin,florfenicol and enrofloxacin). This study will help to validate the classification and virulence of pathogenic bacteria in amphibians.

Ionizable drug delivery systems for efficient and selective gene therapy

Gene therapy has shown great potential to treat various diseases by repairing the abnormal gene function.However,a great challenge in bringing the nucleic acid formulations to the market is the safe and effective delivery to the specific tissues and cells.To be excited,the development of ionizable drug delivery systems(IDDSs)has promoted a great breakthrough as evidenced by the approval of the BNT162b2 vaccine for prevention of coronavirus disease 2019(COVID-19)in 2021.Compared with conventional cationic gene vectors,IDDSs can decrease the toxicity of carriers to cell membranes,and increase cellular uptake and endosomal escape of nucleic acids by their unique pH-responsive structures.Despite the progress,there remain necessary requirements for designing more efficient IDDSs for precise gene therapy.Herein,we systematically classify the IDDSs and summarize the characteristics and advantages of IDDSs in order to explore the underlying design mechanisms.The delivery mechanisms and therapeutic applications of IDDSs are comprehensively reviewed for the delivery of plasmid DNA(pDNA)and four kinds of RNA.In particular,organ selecting considerations and high-throughput screening are highlighted to explore efficiently multifunctional ionizable nanomaterials with superior gene delivery capacity.We anticipate providing references for researchers to rationally design more efficient and accurate targeted gene delivery systems in the future,and indicate ideas for developing next generation gene vectors.

Thansgenic peanut plants obtained by particle bombardment via somatic embryogenesis regeneration system

After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene. Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin. Under continuous selection, hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons. The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR (polymerase chain reaction) for the intron-gus gene and by Southern hybridization of the hph gene. GUS enzyme activity was detected in leaflets from transgenic plants but not from control, non-transformed plants. The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.

Preliminary Investigation on Regulating Effects of Different TCM Treatments on Transcription of the Correlated Genes of Liver Cancer in Rats

The regulating effects of TCM treatments including clearing away heat and toxic materials,promoting blood circulation and removing blood stasis,and strengthening the spleen and regulating qi on the oncogene transcription were observed in the liver cancer model rats.The preliminary results indicated that the mRNA levels of H-ras N-ras and K-ras,and signal molecules correlated with the ras/MAPK signal transduction pathway were down-regulated by the different TCM treatments in varying degrees.Also,the regulating effects of the treatments on differently-displayed genes were discrepant.It is suggested that the molecular mechanisms of the TCM treatments for liver cancer was complex with different target genes.

Association between Maternal Drug Use and Cytochrome P450 Genetic Polymorphisms and the Risk of Congenital Heart Defects in Offspring

Objective This study aimed to assess the associations between maternal drug use,cytochrome P450(CYP450)genetic polymorphisms,and their interactions with the risk of congenital heart defects(CHDs)in offspring.Methods A case-control study involving 569 mothers of CHD cases and 652 controls was conducted from November 2017 to January 2020.Results After adjusting for potential confounding factors,the results show that mothers who used ovulatory drugs(adjusted odds ratio[a OR]=2.12;95% confidence interval[CI]:1.08-4.16),antidepressants(a OR=2.56;95%CI:1.36-4.82),antiabortifacients(a OR=1.55;95%CI:1.00-2.40),or traditional Chinese drugs(a OR=1.97;95%CI:1.26-3.09)during pregnancy were at a significantly higher risk of CHDs in offspring.Maternal CYP450 genetic polymorphisms at rs1065852(A/T vs.A/A:OR=1.53,95%CI:1.10-2.14;T/T vs.A/A:OR=1.57,95%CI:1.07-2.31)and rs16947(G/G vs.C/C:OR=3.41,95%CI:1.82-6.39)were also significantly associated with the risk of CHDs in offspring.Additionally,significant interactions were observed between the CYP450 genetic variants and drug use on the development of CHDs.Conclusions In those of Chinese descent,ovulatory drugs,antidepressants,antiabortifacients,and traditional Chinese medicines may be associated with the risk of CHDs in offspring.Maternal CYP450 genes may regulate the effects of maternal drug exposure on fetal heart development.

THE CLINICAL SIGNIFICANCE OF MULTIDRUG RESISTANCE GENE(mdr1) EXPRESSION IN ACUTE LEUKEMIA

Objective: To study the clinical significance of multidrug resistance gene expression in acute leukemia. Methods: The relationships between drug resistance of leukemia cells and prognosis, multidrug resistance gene (mdr1) were examined in 85 patients with acute leukemia and 20 normal controls by reverse transcriptase polymerase chain reaction (RTPCR). Results: The mdr1 positive rate in untreated group was 44.7%. The complete remission (CR) rate of mdr1 positive patients (23.9%) was significantly lower than that of mdr1 negative patients (88.5%) (P<0.005). The mdr1 expression level in relapsedrefractory group was higher than that of CR group. A gradually increased mdr1 mRNA level in CR patients indicated early relapse. Conclusion: The mdr1 positive rate in normal control and longterm survival patients was very low. The mdr1 expression was correlated with FrenchAmericanBritish Cooperative Group (FAB) classification. The mdr1 expression level was correlated with chemotherapeutic effect and prognosis. It is an unfavorable prognostic factor for patients with acute leukemia.

Liposome-mediated Functional Expression of Multiple Drug Resistance Gene in Human Bone Marrow CD34^+ Cells

Summary: The expression and functional activity of multiple drug resistance (MDR1) gene in human normal bone marrow CD34+ cells was observed. Human normal bone marrow CD34+ cells were enriched with magnetic cell sorting (MACS) system, and then liposome-mediated MDR1 gene was transferred into bone marrow CD34+ cells. Fluorescence-activated cell sorter was used to evaluate the expression and functional activity of P-glycoprotein (P-gp) encoded by MDR1 gene. It was found that the purity of bone marrow CD34+ cells was approximately (91±4.56) % and recovery rate was (72.3±2.36) % by MACS. The expression of P-gp in the transfected CD34+cells was obviously higher than that in non-transfected CD34+ cells. The amount of P-gp in non-transfected CD34+ cells was (11.2±2.2) %, but increased to (23.6±2.34) % 48 h after gene transfection (P<0.0l). The amount of P-gp was gradually decreased to the basic level one week later. The accumulation and extrusion assays showed that the overexpression of P-gp could efflux Rh-123 out of cells and there was low fluorescence within the transfected cells. The functional activity of P-gp could be inhibited by 10 μg/ml verapamil. It was suggested that the transient and highly effective expression and functional activity of P-gp could be obtained by liposome-mediated MRD1 transferring into human normal bone marrow CD34+ cells.

Expression and Prognostic Significance of Multidrug Resistance Associated Protein (MRP) Gene in Non-small Cell Lung Cancer by in Site Hybridization

Objective: To study on the effect of MRP gene overexpression on prognosis of patients with non-small lung cancer (NSCLC). Methods: Paraffin-embedded tissues from 47 cases of NSCLC who had undergone radical tumor resection were examined for expression of MRP gene mRNA by in situ hybridization using labelled digoxigenin probes combined with immunohistochemistry. All the patients were retrospectively followed-up. Results: All of the 47 lung cancer specimens were found to have overexpression of MRP gene mRNA. It was significantly correlated with patients' survival time, response to chemotherapy, recurrence or metastases after surgery, but was not correlated with histology, tumor size, node status, TNM stage, degree of differentiation, age and sex. Conclusion: Overexpression of MRP gene is a marker of prognostic significance in patients with NSCLC.

Insights on drug and gene delivery systems in liver fibrosis

Complications of the liver are amongst the world’s worst diseases.Liver fibrosis is the first stage of liver problems,while cirrhosis is the last stage,which can lead to death.The creation of effective anti-fibrotic drug delivery methods appears critical due to the liver’s metabolic capacity for drugs and the presence of insurmountable physiological impediments in the way of targeting.Recent breakthroughs in anti-fibrotic agents have substantially assisted in fibrosis;nevertheless,the working mechanism of anti-fibrotic medications is not fully understood,and there is a need to design delivery systems that are well-understood and can aid in cirrhosis.Nanotechnology-based delivery systems are regarded to be effective but they have not been adequately researched for liver delivery.As a result,the capability of nanoparticles in hepatic delivery was explored.Another approach is targeted drug delivery,which can considerably improve efficacy if delivery systems are designed to target hepatic stellate cells(HSCs).We have addressed numerous delivery strategies that target HSCs,which can eventually aid in fibrosis.Recently genetics have proved to be useful,and methods for delivering genetic material to the target place have also been investigated where different techniques are depicted.To summarize,this review paper sheds light on themost recent breakthroughs in drug and gene-based nano and targeted delivery systems that have lately shown useful for the treatment of liver fibrosis and cirrhosis.

In vitro study of the influence of GST-π gene transfer on drug-resistance of human cord blood CD34^+ cells

Objective:To investigate the influence of GST-π gene transfer on drug-resistance of human cord blood CD34 + cells.Methods:CD34 + cells were purified from cord blood from normal full-term pregnancy.Gene transduction into human cord blood CD34 + cells was carried out using GST-π gene containing retrovirus vector.The GST-π gene expression in transduced CD34 + cell was confirmed by RT-PCR.After confirmation of GST-π gene transfer,the transfected CD34 + cells were cultured by colony assay in the presence of carboplatin.Results:GST-π mRNA was detected in 30% of CFU-GM derived from GST-π gene transduced CD34 + cells.In vitro drug resistance test showed that the number of CFU-GM formed was significantly higher (2～3 fold) in GST-π gene transduced CD34 + cells than untransduced CD34 +cells.Conclusion:GST-π gene transfer can confer resistance to hematopoietic progenitors against carboplatin in vitro.