Treatment of adult congenital anal atresia with rectovestibular fistula: A rare case report.

BACKGROUND: Female anorectal malformation is a correctable congenital defect. Delayed manifestations in patients with anal deformities are uncommon, especially after adolescence. CASE SUMMARY: The clinical data of a 19-year-old adult female patient with congenital anal atresia accompanied by rectovestibular fistula as the main manifestation was retrospectively analyzed. Diagnosis was made based on the patient's clinical symptoms, signs, imaging showing the fistula, X-ray and magnetic resonance imaging results. The preoperative examination was improved. Anorectoplasty was performed. The patient exhibited an improvement in quality of life and presented no evidence of fecal incontinence during the 6-mo follow-up. CONCLUSION: Transfistula anorectoplasty is a reasonable and reliable surgical method for the treatment of adult congenital anal atresia and rectovestibular fistula.

Expression and clinical significance of Notch signaling genes in colorectal cancer.

The objective of this study was to explore the expression and clinical significance of Notch signaling genes in colorectal cancer. Colorectal cancer samples were prospectively collected from patients post-surgery at the 3rd Affiliated Hospital, Nanjing University of Traditional Chinese Medicine. Immunohistochemistry of tissue arrays was used to analyze the samples and genes involved in the Notch signaling pathway. Microsatellite instability (MSI) was detected by fluorescence multiplex polymerase chain reaction. A total of 146 colorectal cancer samples were collected, including 84 men (57.7%) and 62 women (42.5%). The average age of the study population was 60.8 ± 10.5 years. Notch1 and Notch2 gene expression correlated with tumor pathology type and degree of differentiation. In addition, Jagged 1 (JAG1) and hairy enhancer of split 1 gene expression correlated with the degree of tumor differentiation. Delta-like 1 gene expression varied significantly with tumor location. There was a significant difference between gene expression and MSI. Of the 138 patients, 134 (91.8%) participated in on-site visits, and the average follow-up time was 42.3 ± 13.3 months. During this period, 86 patients (71.6%) were tumor-free. At 1 year post-surgery, 93% of patients were alive, 74% of patients lived for 3 years, and 67% of patients lived for 5 years. The log-rank test was used to perform univariate analysis, and the COX proportional hazards model was used for the multivariate analysis. Based on these analyses, tumor prognosis correlated with the TNM stage, pathological type, microsatellite status as well as Notch2 and JAG1 gene expression. Patients expressing high levels of Notch2 and JAG1 presented with a significantly better prognosis compared to patients expressing negative or weak levels of Notch2 and JAG1. The expression levels of genes associated with the Notch signaling pathway correlated with tumor pathology and the degree of differentiation. In addition, Notch2 and JAG1 expression levels correlated with survival; however, the underlying mechanism for these correlations remains unclear.

Separation and purification of Escherichia coli-expressed human thymosin-α1 using affinity chromatography and high-performance liquid chromatography.

In this study, a human thymosin-α1 (hTα1) fusion protein was overexpressed in Escherichia coli (E. coli). The hexahistidine-tagged hTα1 fusion protein was obtained in soluble form in cells of the engineered E. coli strain BL21 (DE3)/pET-28a-hTα1 that had been induced with isopropyl -D-1-thiogalactopyranoside (IPTG). The recombinant protein accounted for approximately 50-60% of the total protein. We then developed and validated a separation method for hTα1 from E. coli cells based on thermal denaturation, nickel-resin affinity chromatography and high-performance liquid chromatography. The purification method showed good reproducibility and was easy to operate. Purified recombinant hTα1 of high homogeneity was characterized and found to be of high purity (over 99%), as determined by high-voltage electrophoresis and high-performance liquid chromatography analysis. Isoelectric focusing analysis indicated a pI of approximately 4.0, and full wavelength screening showed an optimal absorbance wavelength at around 214nm.

[Expression pattern and clinical significance of hairy enhancer of split 1 in colorectal cancer].

OBJECTIVE: To explore the roles of hairy enhancer of split 1 (Hes1) gene in colorectal cancer and analyze its clinical significance. METHODS: A total of 146 cases with colorectal cancer at our hospital were collected prospectively and followed up. There were 84 males and 62 females with an average age of (61 ± 11) years old. Tissue microarray was prepared and the expression of Notch signal genes were detected by immunohistochemical staining. RESULTS: The differential expressions of Hes1 were significant among various types [negative or weakly positive: 8% (12/146), positive(+): 77% (112/146), positive(++): 15% (22/146)]. Among all, 134 were followed up successfully for an average duration of (42 ± 13) months. According to the Kaplan-Meier life curve, the overall 1, 3 and 5-year survival rates were 93% (136/146), 74% (108/146) and 67% (98/146) respectively. The long-term survival rate was correlated with TNM stage and pathological types (all P = 0.000), but not with Hes1 (P = 0.267). CONCLUSION: The expression of Hes1 is correlated with pathological types and differentiation types. However the long-term survival rate is not correlated with its expression.

[Impact of polyamidoamine dendrimer liposome on the cellular uptake and cytotoxicity of colonic cancer cells].

OBJECTIVE: To evaluate the effects of polyamidoamine dendrimer (PAMAM) liposome as gene carriers on the cellular uptake and its cytotoxicity in colonic cancer cell. METHODS: The liposome modified PAMAM was synthesized with liposome and polyamidoamine dendrimer. Plasmid PEGFP-N1 was mixed with the liposome-modified PAMAM or unmodified PAMAM to form nanoparticle complexes. The shape and size of the nanoparticle complexes were observed by transmission electron microscope and the zeta potential was measured by analytical tool. The encapsulating efficiency was determined by ultraviolet spectrophotometer in centrifuging method. After the cell lines SW620 (colonic cancer cell), MCF-7 (breast cancer cell), ECV304 (vascular endothelial cell) were transfected by the two kinds of PAMAM nanoparticle complexes, the flow cytometry was used to determine the uptake of enhanced green fluorescent protein (EGFP) gene. The cytotoxicity of PAMAM liposome nanoparticles and PAMAM nanoparticles was evaluated by MTT assay. RESULTS: The diameter of liposome modified PAMAM complex was (192 ± 16) nm, and that of PAMAM complex was (189 ± 19) nm (P > 0.05); and the zeta potential of liposome modified PAMAM complex was higher than that of PAMAM complex [(42 ± 7) mV vs. (32 ± 7) mV, P < 0.05]. There was no significant difference in envelopment rate between the two groups [(82 ± 7)% vs. (84 ± 6)%, P > 0.05]. After the colonic cancer cell line SW620 was transfected with the two kinds of PAMAM nanoparticle complexes, the cellular uptake of the cells with the liposome-modified PAMAM complex was significantly higher than that of the cell with PAMAM complex (P < 0.05). The cellular survival rate of the cell lines with liposome-modified PAMAM complex was significantly higher than that of cell lines with PAMAM complex (P < 0.05). CONCLUSION: The liposome modified PAMAM can improve gene transfection efficiency and suppress its cytotoxicity.

[Tea polyphenol inhibits colorectal cancer with microsatellite instability by regulating the expressions of HES1, JAG1, MT2A and MAFA].

OBJECTIVE: To investigate the mechanism of tea polyphenol in inhibiting microsatellite instability (MSI) of colorectal cancer. METHODS: Using LoVo cells and SW480 cells treated with aqueous solution of tea polyphenol, cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) method, changes in microsatellite sequences were detected by genescan method and changes in gene expression of LoVo cells were detected by illumina expression arrays and quantitative real-time polymerase chain reaction (PCR). RESULTS: The proliferation inhibition rates of LoVo and SW480 cells treated with tea polyphenol increased with the increasing of drug concentration and showed an increasing tendency with time. The proliferation inhibition rate of LoVo cells with tea polyphenol was higher than that of SW480 cells, and there was a significant difference in the proliferation inhibition rates at 24 h, 72 h and one week. The microsatellite sequence of LoVo cells treated with tea polyphenol remained stable. The gene expression arrays and quantitative real-time PCR suggested that tea polyphenol inhibited the gene expressions of MT2A, MAFA, HES1 and JAG1 nearly two-fold over controls. It was also found that tea polyphenol inhibited the BAX and p38 genes with a more than two-fold difference but did not significantly inhibit the nuclear factor-κB pathway. CONCLUSION: Tea polyphenol significantly inhibited the proliferation of MSI colorectal cancer cells and stably maintained the microsatellite state in MSI colorectal cancer. Tea polyphenol inhibited the gene expressions of HES1, JAG1, MT2A and MAFA, up-regulated the gene expression of BAX and down-regulated that of P38. Further research is required to investigate how these pathways are interrelated.

Epigallocatechin gallate inhibits dimethylhydrazine-induced colorectal cancer in rats.

BACKGROUND: Epigallocatechin gallate (EGCG) is a polyhydroxy phenolic compound extracted from tea and its antitumor effect has received widespread attention. We explored the inhibitory effect of EGCG on dimethylhydrazine (DMH)-induced colorectal cancer (CRC) using a rat model, predicted the interaction between EGCG and CRC target genes using a database, and explained the EGCG associated target pathways and mechanisms in CRC. AIM: To understand the inhibitory mechanisms of EGCG on CRC cell proliferation and identify its pharmacological targets by network pharmacology analysis. METHODS: DMH (40 mg/kg, s.c., twice weekly for eight weeks) was used to induce CRC in rats. After model establishment, the rats were administered with EGCG (50, 100, or 200 mg/kg, p.o., once daily for eight weeks) and killed 12 and 20 wk after the start of the experiment. Formation of aberrant crypt foci and tumor was studied by histological analysis. Using network pharmacology analysis, candidate and collective targets of EGCG and CRC were identified, and Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes analyses were used to predict the pathways altered by EGCG. RESULTS: At week 12, high-dose EGCG treatment significantly reduced the tumor formation rate, total number of tumors, cancerous and non-cancerous tumors, tumor volume, ascites formation, and aberrant crypt foci count. At week 20, all three doses of EGCG were effective. Seventy-eight collective targets of EGCG and CRC were identified, of which 28 genes were dysregulated in CRC. Kyoto Encyclopedia of Genes and Genomes and GO analyses showed that the dysregulated genes were enriched in hsa05210 (CRC), hsa04115 (p53 signaling pathway), and hsa04151 (PI3K-Akt signaling pathway), GO:0043124 (negative regulation of I-kappaB kinase/NF-kappaB signaling pathway), GO:0043409 (negative regulation of mitogen-activated protein kinase cascade), and GO:2001244 (positive regulation of intrinsic apoptotic signaling pathway) respectively. CONCLUSION: EGCG inhibits the formation of DMH-induced CRC by regulating key pathways involved in tumorigenesis.

Factors associated with failure of the artificial bowel sphincter: a study of over 50 cases from Cleveland Clinic Florida.

PURPOSE: This study investigated the risk factors related to artificial bowel sphincter infection, complications, and failure. METHOD: Complications may occur at any time after artificial bowel sphincter implantation. Early-stage complication is defined as any complications that occurred before artificial bowel sphincter activation, whereas late-stage complications are defined as any complications that occurred after device activation. Assessment of the outcomes of all artificial bowel sphincter operations included evaluation of factors related to patient demographics, operative procedures, and postoperative events. RESULT: From January 1998 to May 2007, 51 artificial bowel sphincter implantations were performed in 47 patients (43; 84.3% female) with a mean age of 48.8 +/- 12.5 (range, 19-79) years and a mean incontinence score of 18 +/- 1.4 (range, 0-20). In 24 patients (54.5%), the etiology of incontinence was secondary to imperforate anus; 15 (24.2%) patients had obstetric injury or anorectal trauma. Twenty-three (41.2%) artificial bowel sphincter implantations became infected, 18 (35.3%) of which developed early-stage infection, whereas 5 (5.9%) had late-stage infection. One patient in the latter group had associated erosion, and two patient had fistula formation. Late-stage complications continued to increase with time. Multivariate analysis revealed that the time between artificial bowel sphincter implantation and first bowel movement and a history of perineal sepsis were independent risk factors for early-stage artificial bowel sphincter infection. CONCLUSION: The time from implantation to first bowel movement and history of perineal infection were risk factors for early-stage artificial bowel sphincter infection and failure. Late-stage failures were more often the result of device malfunction and indicated the need for mechanical refinement.

Symptomatic gallstones after sleeve gastrectomy.

BACKGROUND: Cholelithiasis is a common complication after bariatric surgery. Pure restrictive procedures such as sleeve gastrectomy and gastric banding theoretically should result in less gallstone formation because the food continues to follow the normal gastrointestinal transit, maintaining the enteric-endocrine reflex intact. To the authors' knowledge, the literature has no studies that analyze the incidence of gallstone formation after sleeve gastrectomy. This study aimed to compare the rates of symptomatic gallstones between laparoscopic Roux-en-Y gastric bypass (RYGBP) and sleeve gastrectomy (SG). METHODS: A retrospective chart review of patients who underwent laparoscopic RYGBP and SG between 2004 and 2006 was performed. The patients with previous cholecystectomy, known gallstones with or without concomitant cholecystectomy, and previous weight-reduction operations were excluded from the analysis. The outcome measures were the numbers of patients who had experienced symptomatic and complicated gallstones. Using Cox regression analysis, comparisons was made between the patients with laparoscopic RYGBP (group A) and those with laparoscopic SG (group B). RESULTS: Groups A excluded 174 (26%) of 670 patients, and group B excluded 27 (34.2%) of 79 patients. The patients in group A had a significantly higher preoperative body mass index (BMI) than those in group B. Additionally, more group A than group B patients had a BMI exceeding 45 and more than a 25% loss of original weight. No significant difference in the development of symptomatic (8.7% vs. 3.8%; p = 0.296) or complicated (1.8% vs. 1.9%; p = 0.956) gallstones was noted between the two groups CONCLUSIONS: There was no significant difference in symptomatic or complicated gallstone disease between the patients treated with laparoscopic SG and those treated with laparoscopic RYGBP. Routine prophylactic cholecystectomy should not be recommended for weight reduction during laparoscopic SG.

Clinical features and mismatch repair genes analyses of Chinese suspected hereditary non-polyposis colorectal cancer: a cost-effective screening strategy proposal.

China has the largest numbers of hereditary non-polyposis colorectal cancer (HNPCC) patients based on its population of 1.4 billion. However, the clinical data and mismatch repair (MMR) gene analyses have been limited. Here we performed microsatellite instability (MSI) and immunohistochemistry (IHC) analyses on a series of patients with a high-risk for HNPCC: 61 patients with family histories fulfilling Amsterdam criteria II (ACII-HNPCC) or suspected HNPCC criteria (S-HNPCC), and 106 early onset colorectal cancer (CRC) patients. Sixty late-onset CRC patients were used as control. Methylation of the hMLH1 promoter was analyzed on tumors lacking hMLH1 expression. MMR germ-line mutations were screened on patients with tumors classified as MSI-H/L or negative for IHC. We identified 27 germ-line MMR variants in the 167 patients with a high-risk for HNPCC while only one germ-line mutation in hMSH6 was found in the late-onset CRC group. Of those, 23 were pathogenic mutations. The high incidence of gastric and hepatobiliary cancers coupled with the increasing number of small families in China reduces the sensitivity (43.5%, 30.4%) and positive predictive value (PPV) (45.5%, 17.9%) of the ACII- or S-HNPCC criteria. MSI or IHC testing are highly sensitive in detecting pathogenic mutations (sensitivities = 91.3% and 95.6%, respectively), but the PPVs are quite low (25.6% and 27.8%, respectively). Considering that all 12 tumors with pathogenic mutations in hMLH1 also showed promoter unmethylation, the sensitivity of IHC in conjunction with hMLH1 promoter methylation analysis is not reduced, but the PPV was increased from 27.8% to 61.1%, and the total cost was greatly reduced.

Detection of mismatch repair gene germline mutation carrier among Chinese population with colorectal cancer.

BACKGROUND: Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant syndrome. The National Cancer Institute (NCI) has recommended the Revised Bethesda guidelines for screening HNPCC. There has been a great deal of research on the value of these tests in other countries. However, literature about the Chinese population is scarce. Our objective is to detect and study microsatellite instability (MSI) and mismatch repair (MMR) gene germline mutation carriers among a Chinese population with colorectal cancer. METHODS: In 146 prospectively recruited consecutive patients with clinically proven colorectal cancer, MSI carriers were identified by analysis of tumor tissue using multiplex fluorescence polymerase chain reaction (PCR) using the NCI recommended panel and classified into microsatellite instability-low (MSI-L), microsatellite instability-high (MSI-H) and microsatellite stable (MSS) groups. Immunohistochemical staining for MSH2, MSH6 and MLH1 on tissue microarrays (TMAs) was performed, and methylation of the MLH1 promoter was analyzed by quantitative methylation specific PCR (MSP). Germline mutation analysis of blood samples was performed for MSH2, MSH6 and MLH1 genes. RESULTS: Thirty-four out of the 146 colorectal cancers (CRCs, 23.2%) were MSI, including 19 MSI-H CRCs and 15 MSI-L CRCS. Negative staining for MSH2 was found in 8 CRCs, negative staining for MSH6 was found in 6 CRCs. One MSI-H CRC was negative for both MSH6 and MSH2. Seventeen CRCs stained negatively for MLH1. MLH1 promoter methylation was determined in 34 MSI CRCs. Hypermethylation of the MLH1 promoter occurred in 14 (73.7%) out of 19 MSI-H CRCs and 5 (33.3%) out of 15 MSI-L CRCs. Among the 34 MSI carriers and one MSS CRC with MLH1 negative staining, 8 had a MMR gene germline mutation, which accounted for 23.5% of all MSI colorectal cancers and 5.5% of all the colorectal cancers. Five patients harbored MSH2 germline mutations, and three patients harbored MSH6 germline mutations. None of the patients had an MLH1 mutation. Mutations were commonly located in exon 7 and 12 of MSH2 and exon 5 of MSH6. Right colonic lesions and mucinous carcinoma were not common in MSI carriers. CONCLUSION: Our data may imply that the characteristics of HNPCC in the Chinese population are probably different from those of Western countries. Application of NCI recommended criteria may not be effective enough to identify Chinese HNPCC families. Further studies are necessary to echo or refute our results so as to make the NCI recommendation more universally applicable.

[Anticancer effects of tea polyphenols on colorectal cancer with microsatellite instability in nude mice].

OBJECTIVE: To study the anticancer effects of tea polyphenols on colorectal cancer with microsatellite instability (MSI) in nude mice and to explore its mechanism. METHODS: A colostomy was performed on the caecum of nude mice. Tumor fragments collected from the subcutaneous tumor of hMSH2-absence colon carcinoma Lovo cell line were surgically implanted onto the submucosa of the caecum during colostomy to establish the model. Then, the nude mice were divided into untreated group and 50, 75 and 100 mg/kg tea polyphenols groups. The mice in tea polyphenols-treated groups were given intra-abdominal injection of 50, 75 and 100 mg/kg tea polyphenols respectively. The inhibition rates of tumors were calculated, and microsatellite instability (MSI) and the alteration of transforming growth factor-beta1 (TGF-beta1), TGF-beta2 and insulin-like growth factor (IGF) were detected by Genescan method at different times after the injection. RESULTS: The tumor volumes of the three groups began to decrease at the 1st week and decreased most greatly from 2 to 3 weeks after treatment, and then the tumors tended to increase. The study found that tea polyphenols could inhibit the tumor growth. The tumor inhibition rates in the three treated groups were significantly higher than those in untreated group 1, 2, 3 and 4 weeks after treatment (P<0.01). Detection of MSI showed that the colorectal tumor in the untreated group presented with four MSI signs, including BAT-25, D2S123, D5S346 and D17S250, and TGF-beta1, TGF-beta2, IGF expressions. After using the tea polyphenols, the microsatellite tended to become stable. CONCLUSION: Tea polyphenols can inhibit the mismatch-repair-gene deficient colorectal cancer in nude mice by down-regulating the microsatellite instability.

[Screening the hereditary nonpolyposis colorectal cancer by revised Bethesda guideline: a cohort study of 110 cases].

OBJECTIVE: To study the value of screening hereditary nonpolyposis colorectal cancer (HNPCC) by the revised Bethesda guideline and the rate of HNPCC in colorectal cancer (CRC). METHOD: Tumor tissues and normal colorectal mucous membrane tissues were collected from 110 successive cases with CRC, 66 males and 42 females, aged 60.8 (26 - 94). Fluorescence multiplex polymerase chain reaction was used to detect the microsatellite instability (MSI). The peripheral blood samples were collected from the patients with MSI, genomic DNA was extracted, and PCR and DNA sequencing were used to detect the germline mutations of hMSH2, hMSH6, and hMLH1. RESULTS: Twenty-three out of the 110 patients (20.9%), 12 males and 22 females, aged 57 (47 - 94), had MSI. Seven germline mutations were found in these 23 MSI patients, accounting for 6.4% among the 110 CRC patients, including 3 cases of hMSH2 mutation, 3 cases of hMSH6 mutation, and 1 case of mutation of hMLH1. CONCLUSION: Screened by revised Bethesda guideline, the rate of MSI CRC is 20.9% and the rate of HNPCC is 6.4%. The missence germline mutations of hMSH2 and hMSH6 are more common in the Chinese patients with CRC.

Molecular Diversity of Sapovirus Infection in Outpatients Living in Nanjing, China (2011-2013).

Aim. To gain insight into the molecular diversity of sapovirus in outpatients with acute gastroenteritis in Nanjing, China. Methods. The specimens from outpatients clinically diagnosed as acute gastroenteritis were detected by real-time PCR; RT-PCR was then performed to amplify part of VP1 sequences. The PCR products were cloned into pGEM-T Easy vector and bidirectionally sequenced. All sequences were edited and analyzed. A phylogenetic tree was drawn with the MEGA 5.0 software. Results. Between 2011 and 2013, 16 sapovirus positive cases were confirmed by real-time PCR. The infected cases increased from two in 2011 and six in 2012 to eight in 2013. The majority was children and the elderly (15, 93.75%) and single infections (15, 93.75%). Of the 16 real-time positive specimens, 14 specimens had PCR products and the analysis data of the 14 nucleic sequences showed that there was one GI genogroup with four genotypes, two GI.2 in 2011, three GI.2, and one GI.1 in 2012 and one GI.2, three GI.1, two GI.3, and two GI.5 in 2013. Conclusion. Our data confirmed continuous existing of GI genogroup and GI.2 genotype from 2011 to 2013 in Nanjing and the successive appearance of different genotypes from outpatients with gastroenteritis.

Measurement system that improves the accuracy of polyp size determined at colonoscopy.

AIM: To assess the accuracy of polyp size using an endoscopic lesion measurement system (ELMS). METHODS: The accuracy of polyp size assessment was compared among measurements acquired by visual estimation, disposable graduated biopsy forceps (DGBF; used as a "scale-plate") and the ELMS. RESULTS: There were 192 polyps from 166 cases included in this study. The mean diameter of the post polypectomy measurement was 0.85±0.53 cm (range: 0.2-3.0 cm). The mean diameter by visual estimation was 1.10±0.53 cm, which was significantly different compared to the actual size of the polyp (P<0.001). The mean diameters obtained using DGBF (0.87±0.54 cm) and ELMS (0.85±0.53 cm) did not significantly differ from the actual size of the polyp. The difference between the measurements from the ELMS and DGBF was not significant. CONCLUSION: Unlike visual estimations at colonoscopy, endoscopic graduated biopsy forceps and the endoscopic lesion measurement system are accurate methods to estimate polyp size.

Use of disposable graduated biopsy forceps improves accuracy of polyp size measurements during endoscopy.

AIM: To determine the accuracy of endoscopic polyp size measurements using disposable graduated biopsy forceps (DGBF). METHODS: Gradations accurate to 1 mm were assessed with the wire of disposable graduated biopsy forceps. When a polyp was noted, endoscopists determined the width of the polyp; then, the graduated biopsy forceps was inserted and the largest diameter of the tumor was measured. After excision, during surgery or endoscopy, the polyp was measured using the vernier caliper. RESULTS: One hundred and thirty-three colorectal polyps from 119 patients were studied. The mean diameter, by post-polypectomy measurement, was 0.92 ± 0.69 cm; 83 were < 1 cm, 36 were between 1 and 2 cm, and 14 were > 2 cm. The mean diameter, by visual estimation, was 1.15 ± 0.88 cm; compared to the actual size measured using vernier calipers, the difference was statistically significant. The mean diameter measured using the DGBF was 0.93 ± 0.68 cm; compared to the actual size measured using vernier calipers, this difference was not statistically significant. The ratio between the mean size estimated by visual estimation and the actual size was significantly different from that between the mean size estimated using the DGBF and the actual size (1.26 ± 0.30 vs 1.02 ± 0.11). CONCLUSION: The accuracy of polyp size estimation was low by visual assessment; however, it improved when the DGBF was used.

Genetic detection of Chinese hereditary nonpolyposis colorectal cancer.

AIM: To explore the germline mutations of the two main DNA mismatch repair genes (hMSH2 and hMLH1) between patients with hereditary non-polyposis colorectal cancer (HNPCC) and suspected (atypical) HNPCC. METHODS: Genomic DNA was extracted from the peripheral blood of the index patient of each family, and germline mutations of hMSH2 and hMLH1 genes were detected by PCR-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing techniques. RESULTS: For PCR-SSCP analysis, 67% (4/6) abnormal exons mobility in typical group and 33% (2/6) abnormal exons mobility in atypical group were recognized. In direct DNA sequencing, 50% (3/6) mutation of MMR genes in typical group and 33% (2/6) mutation of MMR genes in atypical group were found, and 4/6 (66.67%) and 1/6 (16.67%) mutations of hMSH2 and hMLH1 were identified in typical HNPCC and atypical HNPCC, respectively. CONCLUSION: Mutation detection of the patients is of benefit to the analysis of HNPCC and, PCR-SSCP is an effective strategy to detect the mutations of HNPCC equivalent to direct DNA sequence. It seems that there exist more complicated genetic alterations in Chinese HNPCC patients than in Western countries.

[Clinicopathological features of typical and non-typical hereditary non-polyposis colorectal cancer and their germline mutation of hMLH1 and hMSH2].

OBJECTIVE: To study the clinicopathological features of the Chinese hereditary non-polyposis colorectal cancer and its germline mutation of hMLH(1) and hMSH(2). METHODS: Thirteen typical Chinese hereditary non-polyposis colorectal carcinoma (HNPC)C kindreds and 19 non-typical HNPCC families were registered and followed up. The germline mutation of the hMLH(1) and hMSH(2) of 12 index cases of 6 typical and 6 non-typical HNPCC were screened by PCR-SSCP. Samples with abnormal mobility were sequenced directly. RESULTS: The average age of typical HNPCC was 47, no difference existed between sexes. Location of the tumors of typical HNPCC represented 44.7% on the right half colon and non-typical HNPCC 65.8% on the rectum. The rate of the metachronos cancer was 11.5%. The 3-, 5-and 10-year survival rate was 64.0%, 45.3% and 31.2% respectively. Among 12 cases, 8 showed abnormal mobility. Except for an intron polymorphism, six exons abnormalities were found in 5 of 12 proband. Sequencing showed 4 missense, 7 insertion and a nonsense mutations. CONCLUSIONS: Chinese HNPCC is early onset, more common on proximal colon and better prognosis. Mutation of hMSH(2) is dominant in the Chinese typical HNPCC, but mutation of hMLH(1) is more common in the non-typical group.

[The role of the immunohistochemistry for hMLH1 and hMSH2 with detection of microsatellite instability to identify the kindreds with hereditary nonpolyposis colorectal cancer].

OBJECTIVE: To investigate the specificity and sensitivity of the immunohistochemistry for hMLH1 and hMSH2 with detection of microsatellite instability (MSI) to identify the kindreds with hereditary nonpolyposis colorectal cancer and to analyse its value in clinical practice. METHOD: Specimens of 16 cases with HNPCC and 16 cases with sporadic colorectal cancer were detected by immunostaining with hMLH1 and hMSH2 and MSI was also detected. RESULTS: The specificity and sensitivity of the immunohistochemistry for hMLH1 and hMSH2 were 91.7% and 87.5% respectively. The specificity and sensitivity of MSI were 100% and 75.0%. By combining two methods, the specificity and sensitivity were 91.7% and 93.8% respectively. CONCLUSIONS: By combination of the immunohistochemistry for hMLH1 and hMSH2 and detection of MSI to identify the kindreds with HNPCC, the specificity and sensitivity are improved which is better than to use either of them alone. And it is very easy and cheap that it can be used in clinics.

[Experimental study of the impact of hyperlipidemia on the chemotherapy in colorectal cancer model].

OBJECTIVE: To study the effect of hyperlipidemia on the prognosis and therapeutic response for colorectal cancer and to explore the associated mechanism. METHODS: The hyperlipidemic subcutaneous heterotopic colorectal cancer orthotopic transplant model of nude mice was established by feeding high fat diet and performing transplantation. Seventy mice were divided into 7 groups with 10 mice in each group. Two groups were used as pre-experiment. The remaining 5 groups included 4 high-fat groups (G1 to G4), and 1 normal-diet control group (G5). G1, G2, G3, G4, and G5 received normal saline, capecitabine, simvastatin, capecitabine plus simvastatin and capecitabine respectively for 3 weeks. Changes of tumor volume, tumor weight, tumor growth rate and blood lipid parameters (TC, TG, HDL, LDL, Lpa, apoA and apoB) were observed. RESULTS: In G1 to G4, TC, HDL, apoA, TG, LDL, Lpa, apoB increased, but only TC, HDL, apoA were significantly different as compared with G5 (P=0.020, P=0.001, P=0.001, P=0.911, P=0.249, P=0.681, P=0.053). The tumor in G1 grew fastest, and its growth rate was significantly different as compared with G2, G4, G5 except G3 (P=0.001, P=0.806, P=0.001, P=0.010). The tumor growth rate of G3 was lower than group G1, but higher than G2, G4, G5 with significant difference (P=0.001, P=0.002, P=0.016). The tumor of G5 grew faster than G2 and G4, but without significant differences (P=0.051, P=0.070). The tumor of G4 grew slowest without significant difference as compared to G2 (P=0.438). Compared with pre-administration, at the third week, the TC of G1 was increased [(3.8±0.4) mmol/L], while the other 4 groups decreased [G2 (2.8±1.8) mmol/L, G3 (2.9±0.7) mmol/L, G4 (1.4±0.9) mmol/L, G5 (2.1±0.2) mmol/L]. G4 decreased significantly (P=0.004). At the fifth week, the TC of all the 5 groups decreased, while the lipids of G4 were higher as compared to those at the third week. The TG, Lpa, ApoA were significantly decreased at the third week (all P<0.05), while no significant differences were found in HDL and apoB. CONCLUSIONS: A hyperlipidemia colon tumor model involving subcutaneous colon translocation and orthotopic transplantation of nude mice is successfully established. This model is an ideal research model for hyperlipidemia and colorectal cancer. The effect of capecitabine on tumors in hyperlipidemia groups is better as compared to normal diet group. The proliferation of tumor cells can increase serum total serum cholesterol.