Objective To construct the responsive plasmid PTRE-HIF-1αof Tet-on gene expression system and examine its expression. Methods RT-nested PCR was performed on the total RNA extracted from hypoxia HepG2 cells to obtain the cDNA of HIF-1α, which was inserted into the responsive plasmid PTRE2hyg. DNA sequencing was performed after the recombinant of responsive plasmid PTRE-HIF-1α was identified by endonuclease digestion. This recombinant vector was transfected into HepG2Tet-on cells by means of liposome and its expression was examined by RT-PCR and Western blot under the control of deoxycycline. Results The amplified products were confirmed as the cDNA of HIF-1α by DNA sequencing. The responsive plasmid PTRE-HIF-1α verified by edonuclease digestion, was capable of expression in HepG2Tet-on cells and could be controlled by deoxycycline. Conclusion The responsive plasmid PTRE-HIF-1α of Tet-on expression system is constructed successfully, and it can express under the regulation of deoxycycline in the HepG2Tet-on cells.
Objective To analyze the variation of intestinal microflora in patients with colorectal cancer by SYBR GreenⅠreal-time fluorescence quantitative PCR and reveal the role and significance of intestinal microflora in the colorectal cancer-associated molecular pathogenesis. Methods A set of 16S rRNA gene group of species-specific primers for Bifidobacterium spp., Lactobacillus group, Escherichia coli, and ddl gene-targeted species-specific primers for Enterococcus faecalis and feces Enterococcus were designed. Patients with colorectal cancer (colorectal cancer group, n=30) and healthy volunteers (normal control group, n=30) were included and whose feces were collected to extract bacterial genome DNA. SYBR GreenⅠ real-time fluorescence quantitative PCR was used to analyze the five mentioned bacterial amounts. Results Level of Bifidobacterium spp. (4.52±0.49) and Lactobacillus group (5.46±0.12) in colorectal cancer group were significantly lower than those （9.25±0.83 and 7.45±0.37） of normal control group (Plt;0.05), whereas levels of Escherichia coli (5.82±0.47), Enterococcus faecalis (10.6±0.30) and feces Enterococcus (5.74±0.16) in colorectal cancer group were significantly higher than those （4.68±0.32, 4.95±0.24, and 5.03±0.43） of normal control group (Plt;0.05). Conclusions The fecal microflora composition of patients with colorectal cancer is significantly decreased in Bifidobacterium spp. and Lactobacillus group, whereas increased in Escherichia coli, Enterococcus faecalis, and feces Enterococcus. These data underline that the occurrence and progress of colorectal cancer may be related to intestinal microflora.
ObjectiveTo clone full-length cDNA of rat galectin-9 and construct recombinant adenovirus granule containing rat galectin-9 gene. MethodsThe galectin-9 gene was amplified by RT-PCR from rat liver tissue and inserted orientationally into plasmid pDC316-GFP digested by restriction endonucleases NotⅠ and HindⅢ. The recombinant pDC316-GFP-galectin-9 shuttle plasmid was identified by PCR, restriction endonuclease digestion and sequencing, and then co-transfected with rescue plasmid pBHGlox△E1.3Cre into HEK-293 cells by liposome reagent. Recombinant adenovirus vector containing rat galectin-9 gene (Ad5-galectin-9) was generated by sitespecific recombination and confirmed by PCR, and then Ad5-galectin-9 was propagated in HEK-293 cells and purified. The infectious titer of viral stock was determined by TCID50 assay. ResultsConstruction of pDC316-GFP-galectin-9 shuttle plasmid was confirmed to be correct by PCR, restriction endonuclease digestion and sequencing. Construction of recombinant adenovirus Ad5-galectin-9 was confirmed to be correct by PCR. The infective titer of Ad5-galectin-9 was 1.4×109 U/ml. ConclusionRecombinant adenovirus vector containing rat galectin-9 gene (Ad5-galectin-9) is successfully constructed, which provides the foundation of further research on the function of galectin-9 gene.
Objective To identify and observe the pathogenic gene variant and clinical phenotype in a family with Leber congenital amaurosis (LCA). MethodsA retrospective clinical study. Two patients and four family members from one LCA family (type 7), diagnosed via genetic testing at the First Affiliated Hospital of Xi'an Jiaotong University in January 2024 were included. Detailed patient and family histories were collected. All patients underwent examinations including best-corrected visual acuity (BCVA), intraocular pressure, color fundus photography, fundus autofluorescence (FAF), flash visual evoked potential (F-VEP), full-field electroretinography (ff-ERG), and optical coherence tomography (OCT). Family members underwent BCVA and color fundus photography examinations. Peripheral venous blood (5 ml) was collected from the patients and the four family members for genomic DNA extraction. High-throughput sequencing was used to screen for pathogenic gene variants. Identified variants were verified by Sanger sequencing. All variants were classified according to the American College of Medical Genetics and Genomics (ACMG) guidelines. Bioinformatics software including Mutation Taster, Polyphen-2, PROVEAN, and REVEL was used to analyze the pathogenicity of the variants. Results The proband (Ⅱ-2), a 14-year-old female, was born to consanguineous parents (first cousins). Her BCVA was 0.1 in both eyes; intraocular pressure was normal; the anterior segments showed no significant abnormalities. Color fundus photography showed waxy optic discs and a "coin-shaped," "salt-and-pepper" appearance in the retina. FAF revealed large areas of hypoautofluorescence in the macular region. OCT showed shallowing or disappearance of the foveal, disorganized retinal layers, and absence of the ellipsoid zone. F-VEP showed recordable P2 waves with no significant delay in peak time but slightly reduced amplitude. ff-ERG showed significantly reduced or non-detectable amplitudes of the scotopic and photopic a- and b-waves. The proband's elder sister (Ⅱ-1) had similar BCVA and fundus findings. The proband's parents (Ⅰ-1, Ⅰ-2), younger brother (Ⅱ-3), and younger sister (Ⅱ-4) showed no significant ocular phenotypic abnormalities. Genetic testing revealed that the proband and her elder sister were homozygous for the CRX gene variant c.122G>A:p.Arg41Gln. The proband's father, mother, and younger brother were heterozygous carriers of the same CRX variant; the younger sister showed no variation at this locus. Based on the clinical presentation, ff-ERG, and genetic test results, the final diagnosis was LCA type 7. According to ACMG guidelines, the c.122G>A variant was classified as likely pathogenic. Mutation Taster and Polyphen-2 software predicted the variant to be damaging; the REVEL score was 0.929, indicating a likely pathogenic variant. Conclusions The homozygous CRX gene variant c.122G>A:p.Arg41Gln causes autosomal recessive LCA type 7 in this family. LCA is characterized by early onset and severe visual impairment.
Objective To study the effect of chitosan (CS) mediated insul in-l ike growth factor 1 gene (igf-1) transfection on the repair of articular cartilage defect. Methods Twelve 3-month-old healthy male rabbits weighting 2.0-2.5 kg were randomly divided into 2 primary groups, control and intervention groups (n=6 per group). Control group was further divided into normal control (left knee) and normal saline (NS) control (right knee) groups. While, intervention group was divided into CS (left knee) and CS/igf-1 intervention (right knee) groups. Cartilage defects were created in the knee joints except normalcontrol. Intra-articular injections of CS/igf-1 complex was administrated 2 times a week for 4 weeks in CS/igf-1 interventiongroup, 0.5 mL CS in CS intervention group, and 0.5 mL sal ine solution in normal control and sal ine control groups. At 28days after treatments, the cartilage samples were collected for histological observation and collagen type II and aggrecan mRNA evaluation. Results HE staining and toluidine blue staining revealed that CS/igf-1 and CS intervention could significantly stimulated cartilage regeneration accompanied with fibrosis and inflammatory cell infiltration, however, CS/igf-1 treatment resulted in the best repair of cartilage defect. In contrast, sal ine control group only showed fibrous tissue prol iferation and inflammatory cell infiltration without significant cartilage repairing. In terms of collagen type II and aggrecan gene expression, significant differences were observed in each pairwised comparison among 4 groups in the order of CS/igf-1 gt; CS gt; NS gt; normal control (P lt; 0.05). Conclusion In situ CS/ifg-1 complex transfection can enhance the formation of mesochondrium by upregulating collagen type II or aggrecan expression, which might enhance the repair of articular cartilage defect.
Inherited retinal diseases (IRDs) are the major cause of refractory blinding eye diseases, and gene replacement therapy has already made preliminary progress in the treatment of IRDs. For IRDs that cannot be treated by gene replacement therapy, gene editing provides an alternative therapeutic method. Strategies like disruption of pathogenic variants with or without gene augmentation therapy and precise repair of pathogenic variants can be applied for IRDs with various inheritance patterns and pathogenic variants. In animal models of retinitis pigmentosa, Usher syndrome, Leber congenital amaurosis, cone rod cell dystrophy, and other disorders, CRISPR/Cas9, base editing, and prime editing showed the potential to edit pathogenic variations in vivo, indicating a promising future for gene editing therapy of IRDs.
ObjectiveTo explore the influence of patients who accepted chemotherapy of Folfox4 scheme before operation for the expression of miR-196 and HoxB8 in colorectal cancer, and illustrating the differences between the miR-196 and HoxB8 expressions in colorectal cancer tissues and sensitivity to chemotherapy with Folfox4 scheme and its corre-lation and significance. MethodsFluorescence quantitative PCR (RT-PCR) and immunohistochemistry were used to determine the expressions of miR-196 and HoxB8 in 50 specimens of neoadjuvant chemotherapy group (chemotherapy sensitive group and chemotherapy insensitive group) and 30 specimens which received the surgery directly (no-chemo-therapy group), and analyzing the relationship and discrepancy between miR-196 and HoxB8 in these groups. ResultsThe RT-PCR examination showed that the relative expression levels of miR-196 and HoxB8 in the neoadjuvant chemo-therapy group were lower than the no-chemotherapy group (0.646 8±0.683 9 vs.1.000 0±0.000 0, P < 0.01;0.607 6±0.418 9 vs.1.000 0±0.000 0, P < 0.01).Expression of miR-196 in the chemotherapy sensitive group was higher than the chemotherapy insensitive group (0.948 9±0.691 0 vs.0.344 7±0.536 1, P < 0.01), however, the expression of HoxB8 mRNA in the chemotherapy sensitive group was lower than the chemotherapy insensitive group (0.489 9±0.371 5 vs.0.725 3±0.437 5, P < 0.05).Expression positive rate of HoxB8 protein in chemotherapy sensitive group was lower than the chemotherapy insensitive group (Z=-2.396, P=0.017).The expressions of miR-196 and HoxB8 in the neoadjuvant chemotherapy group had negative relationship (r=-0.595, P < 0.01), which was also exist in the no-chemo-therapy group (r=-0.435, P < 0.01). ConclusionsThe neoadjuvant chemotherapy with Folfox4 scheme before oper-ation can reduce the expression levels of miR-196 and HoxB8 in colorectal cancer tisssues.The different expression levels of miR-196 and HoxB8 could influence the sensitivity of neoadjuvant chemotherapy with Folfox4 scheme in colorectal cancer.The high level expression of miR-196 could restrain the expression of HoxB8, and then increase the sensitivity of chemotherapy with Folfox4 scheme in colorectal cancer.
Mesenchymal stem cells (MSC) are considered to have important value in the treatment of various diseases because of their low immunogenicity, transferability, and strong tissue repair capacity. Stromal cell derived factor-1 (SDF-1) and its receptor CXC chemokine receptor 4 (CXCR4) pathway plays an important role in migration of MSC. The induction of homing of MSC to retina by regulating SDF-1/CXCR4 may exert the curative effect on diabetic retinopathy to greatest exent.
Objective To explore the expression and function of NDRG2 gene in human primary hepatocellular carcinoma and normal hepatic tissues. Methods The immunohistochemical ABC method， Western blot， and Real-time PCR were used to investigate the expression and content of NDRG2 in human hepatocellular carcinoma and hepatic normal biopsies. Results The NDRG2 protein located in cytoplasm. The positive rate was 16.67%（5/30） and 100%（30/30） in hepatocellular carcinoma and normal hepatic tissues, respectively. The relative content of NDRG2 protein in hepatocellular carcinoma and normal hepatic tissues were 0.029 0±0.005 9 and 0.109 2±0.002 8. There were significant differences between human hepatocellular carcinoma and hepatic normal biopsies both in staining positive rates and relative content（P＜0.05）. The Western blot also agreed with the result，the expression level of NDRG2 protein in hepatocellular carcinoma and normal hepatic tissues was 1.13±0.15 and 1.57±0.18， respectively, there was significant difference（P＜0.05）. Also, compared with normal hepatic tissues, the expression level of NDRG2 mRNA in carcinoma tissues was reduced significantly (0.89±0.15 vs. 1.48±0.17, P＜0.05). However, there were no significant differences in NDRG2mRNA expression between Edmondson-Steiner grades. Conclusions There possibly have difference in NDRG2 expression between human primary hepatocellular carcinoma and normal hepatic tissue. NDRG2 gene may take part in the pathogenesis of human primary hepatocellular carcinoma. Futher study will be needed to study its mechanism and function.