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.
One of the major clinical characteristics of congenital stationary night blindness(CSNB)is dysfunction of rod photoreceptors of the retina.Rhodopsin,the photosensitive pigment of the rods,is essential for maintaining the normal function of rod photoreceptors.It is resonable to hypothesize that mutations or deletions of rhodopsin gene may be involved in the molecular defect of CSNB.To test this hypothesis,we are searching for rhodopsin gene mutations in patients with autosomal dominant CSNB.In this study,DNA fragments containing the coding sequences in exon 5 of rhodopsin gene were amplified by polymerase chain reaction(PCR)in 15 patients and 5 unaffected members from a large family with autosomal dominant CSNB.RFLP analysis of these DNA fragments demonstrated that in comparison with a control group of 12 normal persons,there is no obvious deletion in exon 5 of rhodopsin gene,and that mutations or deletions do not exist in codon 314,codon 347,and the third base of codon 313 as well as the first base of codon 348 of the rhodopsin gene in these CSNB patients,which suggest the molecular pathogenesis of autosomal dominant CSNB not involve mutations or deletions of these codons of the rhodopsin gene. （Chin J Ocul Fundus Dis,1993,9:66-69）
Objective To investigate the difference of minichromosome maintenance protein 2 (MCM2) mRNA expression among colonic normal mucosa, colonic adenoma and carcinoma. Methods The expressions of MCM2 mRNA were determined by real-time RT-PCR in 12 colonic normal mucosa, 33 colonic adenomas and 12 colonic carcinomas. Data were evaluated by relative expression software tool (REST-XL). Results The expressions of MCM2 mRNA elevated in turn by colonic normal mucosa, adenoma and carcinoma. The expression of MCM2 mRNA in colonic carcinomas was significantly higher than that in adenomas， as well as in normal mucosa (P=0.001), while the difference of MCM2 mRNA expressions between adenoma and normal mucosa was insignificant (P=0.184). Conclusion The difference of MCM2 mRNA expressions between adenoma and carcinoma indicated the potential value on early diagnosis for colonic carcinoma.
Objective To research the expressions of miR-196b and HoxB8 mRNA in colorectal cancer and theircorrelation with clinicopathologic features，and to explore the relationship between miR-196b and HoxB8 in vivo. Methods Expressions of RNA （including miR-196b and HoxB8 mRNA） and HoxB8 protein were detected respectively by using quantitative real-time reverse transcriptase PCR and Western blot in 30 cases of colorectal cancer and corresponding normalmucous membrane tissues. Results In colorectal cancer tissues，expressions of miR-196b and HoxB8 mRNA were higher than those of the corresponding normal mucous membrane tissues （P＜0.05）. Expression of miR196b mRNA was assoc-iated with lymph node metastasis，neoplasm stages （Ⅰ＋ⅡandⅢ＋Ⅳ），and distant metastasis （P＜0.05），on the otherhand，no significant differences were observed regarding tumor site，size，gross type，depth of invasion，tissue differentiation，age，and sex （P＞0.05）. Expression of HoxB8 mRNA was no significant differences concerning lymph node metastasis，tumor stages （Ⅰ＋Ⅱ，Ⅲ＋Ⅳ），distant metastasis，tumor site，size，gross type，depth of invasion，tissue differentiation，age，and sex （P＞0.05）. The expression of miR-196b mRNA was negatively correlated with HoxB8 mRNA expression （r=-0.458，P＜0.05），and HoxB8 protein expression with no obvious correlation （r=-0.236，P＞0.05） in colorectal cancer tissues. Conclusions The expressions of miR-196b and HoxB8 mRNA in colorectal cancer tissues are higher，the high expression of miR-196b mRNA is related to the tumorigenesis and progression of colorectal cancer as well as correlated with prognosis in colorectal cancer. The miR-196b inhibits the expression of HoxB8 mRNA by binding to the3′-UTR of target HoxB8 mRNA.
ObjectiveTo detect the expression of Prox1 (prospero-related homeobox 1) gene in primary hepatocellular carcinoma (HCC), and to analyze the correlation of Prox1 gene expression with pathological grade and clinical stage of HCC. MethodsThe expressions of Prox1 gene in carcinoma tissues and adjacent cancerous tissues in HCC as well as normal liver tissues were detected by semi-quantitative RT-PCR, then the correlation of Prox1 gene expression with HCC pathological grade and clinical stage were analyzed. ResultsThe expression of Prox1 gene in carcinoma tissues (0.243±0.102) and adjacent cancerous liver tissues (0.537±0.235) was significantly lower than that in normal liver tissue (0.812±0.372), respectively （ Plt;0.01 or Plt;0.05）. Furthermore, the expression of Prox1 gene in carcinoma tissues was significantly lower than that adjacent cancerous liver tissues (Plt;0.05). The expressions of Prox1 gene in different pathological grade (F=97.950, Plt;0.001) and clinical stage were significantly different (F=228.300, Plt;0.001), and when compared with each other, the differences of pathological grade and clinical stage were also significant (Plt;0.001 or Plt;0.01). The expressions of Prox1 gene in HCC carcinoma tissue were negatively correlated with pathological grade (r=-0.930, Plt;0.01) and clinical stage (r=-0.980, Plt;0.01) of HCC. ConclusionsExpression of Prox1 gene may be related to the initiation and development of HCC, however, that whether Prox1 gene functions as tumor suppressor in HCC needs further investigation.
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 explore the relationship between the HBsAg positive patients suffering from hepatocellular carcinoma (HCC) and HBV DNA genotype. Methods By using PCR type-specific primers combined with sequencing of genotype, we analyzed the genotype of HBV DNA in the serum of 500 patients with positive HBsAg in our hospital. Among them, 150 cases suffered from HCC. Results Genotype B and C were both predominant genotypes in HBsAg positive patients. But in HCC group, the rate of genotype C was 65.33% （98/150）, which was significantly higher than that in non-HCC group (88/350, 25.14%), while genotype B, in contrast, was 28.67% （43/150） and 68.86% （241/350）， χ2=75.45， Plt;0.05. The distribution of HBV DNA genotype B or genotype C in different gender or different age groups were not statistically significantly different in cases of HCC (Pgt;0.05). Conclusion Genotype C of HBV DNA is more common in patients with HCC, and maybe there is relationship between genotype C and the occurrence of HCC.
Objective To identify micrometastasis in regional lymph nodes of gastric cancer by quantitative real-time reverse transcription-PCR (qRT-PCR) assay and to evaluate the clinical significance of micrometastasis. Methods To study 320 lymph nodes collected from January 2010 to June 2010， 281 of which were from 40 patients with gastric cancer who had undergone a standard gastrectomy with lymphadenectomy， and other 39 of which were from 10 patients with gastroduodenal ulcer. Made CEA， CK-19， and CK-20 as primers， and used qRT-PCR assay in addition to hematoxylin and eosin staining to detect the micrometastasis， and to analyze the clinicopathologic characteristics.Results Totally， micrometastasis were detected by qRT-PCR assay in 31 (15.34%，31/202) lymph nodes of 28 (70.00%， 28/40) patients. Thirty-nine lymph nodes from 10 patients with gastroduodenal ulcer were negative by qRT-PCR and HE staining. The degree of differentiation， depth of gastric mural invasion， and clinical stage had statistically significant correlation with the incidence of lymph node micrometastasis (P＜0.05). Conclusions qRT-PCR assay is a sensitive and specific method to detect lymph node micrometastasis in gastric cancer patients，and it has importantly clinical significance in evaluating clinical staging，prognosis and treatment prescription.
Objective To evaluate the clinical significance of epidermal growth factor receptor EGFR) mutations in the treatment of non-small cell lung cancer ( NSCLC) . Methods Plasma DNAs solated fromblood specimens of 170 NSCLC patients, who were admitted in the First Affiliated Hospital of uangzhou Medical College from December 2005 to December 2007, were subjected to the test of EGFR utant-enriched PCR. The correlation of mutant detection with clinical characteristics was analyzed as well.Results Out of the total 170 patients, EGFR mutations were identified in 77 cases ( 77 /170, 45. 3% ) .EGFR mutations were more frequent in the patients with adenocarcinoma ( P lt; 0. 001) and in the nonsmokers P =0. 001) . In the 33 patients treated with gefitinib, those with mutations ( + ) showed a higher esponse rate and prolonged progression-free survival after the treatment compared with those with mutations( - ) ( P =0. 001 and 0. 001, respectively) . Conclusions EGFR active mutations can be specifically and ensitively detected by EGFR mutant enriched PCR assay. Plasma EGFR mutants detection is valuable in uiding clinical decision.
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.