Multiple Functions of Ten-eleven Translocation 1 during Tumorigenesis / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>Aberrant expression of ten-eleven translocation 1 (TET1) plays a critical role in tumor development and progression. We systematically summarized the latest research progress on the role and mechanisms of TET1 in cancer biology.</p><p><b>DATA SOURCES</b>Relevant articles published in English from 1980 to April 2016 were selected from the PubMed database. The terms "ten-eleven translocation 1," "5mC," "5hmC," "microRNA," "hypoxia," and "embryonic stem cell" were used for the search.</p><p><b>STUDY SELECTION</b>Articles focusing on the role and mechanism of TET1 in tumor were reviewed, including clinical and basic research articles.</p><p><b>RESULTS</b>TET proteins, the key enzymes converting 5-methylcytosine to 5-hydroxymethylcytosine, play vital roles in DNA demethylation regulation. Recent studies have shown that loss of TET1 is associated with tumorigenesis and can be used as a potential biomarker for cancer therapy, which indicates that TET1 serves as tumor suppressor gene. Moreover, besides its dioxygenase activity, TET1 could induce epithelial-mesenchymal transition and act as a coactivator to regulate gene transcription, such as developmental regulator in embryonic stem cells (ESCs) and hypoxia-responsive gene in cancer. The regulation of TET1 is also correlated with microRNA in a posttranscriptional modification process. Hence, it is complex but critical to comprehend the mechanisms of TET1 in the biology of ESCs and cancer.</p><p><b>CONCLUSIONS</b>TET1 not only serves as a demethylation enzyme but also plays multiple roles during tumorigenesis and progression. More studies should be carried out to elucidate the exact mechanisms of TET1 and its associations with cancer before considering it as a therapeutic tool.</p>

Optimization of genomic DNA extraction with magnetic bead- based semi-automatic system / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To develop a rapid and effective method for genomic DNA extraction with magnetic bead-based semi-automatic system.</p><p><b>METHODS</b>DNA was extracted from whole blood samples semi-automatically with nucleic acid automatic extraction system.The concentration and purity of samples was determined by UV-spectrophotometer. Orthogonal design was used to analyze the main effect of lysis time, blood volume, magnetic bead quantity and ethanol concentration on the DNA yield; also the 2-way interaction of these factors.</p><p><b>RESULTS</b>Lysis time, blood volume, magnetic bead quantity and ethanol concentration were associated with DNA yield (P<0.05), but no interaction existed. DNA yield was higher under the condition with 15 min of lysis time, 100 μl of blood volume, 80 μl of magnetic beads and 80 % of ethanol. A significant association was found between the magnetic bead quantity and DNA purity OD260/OD280 (P=0.008). Interaction of blood volume and lysis time also existed (P=0.013). DNA purity was better when the extracting condition was 40 μl of magnetic beads, 15 min of lysis time and 100 μl of blood volume. Magnetic beads and ethanol concentration were associated with DNA purity OD260/OD230 (P=0.017 and P<0.05), the result was better when magnetic beads was 40 μl and ethanol concentration was 80 %.</p><p><b>CONCLUSION</b>The results indicate that the optimized conditions with 40 μl magnetic beads will generate higher quality of genomic DNA from the whole blood samples.</p>

Colorectal cancer, one entity or three / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Understanding of the mechanism of colorectal carcinogenesis has been gaining momentum for some years on account of its high incidence and impact on the lives of individuals affected. Different genetic abnormalities have been found in colorectal cancers from different sites. For example, proximal colon cancer is usually related to the nucleotide instability pathway, as microsatellite instability (MSI). However, distal colon cancer is usually associated with specific chromosomal instability (CIN). The development of cancer at the rectum, though similar to that at the colon, displays its own unique features. These differences might be partially attributed to different embryological development and physiological circumstances. Environmental factors such as diet and alcohol intake also differ in their role in the development of tumors in the three segments, proximal colon, distal colon, and rectum. "Proximal shift" of colon cancer has been known for some time, and survival rates of colorectal cancer are higher when rectal cancers are excluded, both of which emphasize the three different segments of colorectal cancer and their different properties. Meanwhile, colonic and rectal cancers are distinctive therapeutic entities. The concept of three entities of colorectal cancer may be important in designing clinical trails or therapeutic strategies. However, the dispute about the inconsistency of data concerning the site-specific mechanism of colorectal carcinoma does exist, and more evidence about molecular events of carcinogenesis and targeted therapy needs to be collected to definitely confirm the conception.

Hypomethylation of 5'CpG island of insulin-like growth factor binding protein-related protein 1 is associated with its overexpression in colorectal cancer / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the methylation status of 5'CpG island of insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) in colorectal cancer and its relationship with gene expression and clinicopathologic parameters.</p><p><b>METHODS</b>Semi-quantitative reverse transcription-PCR (RT-PCR) was used to detect the expression of IGFBP-rP1 in 46 cases of colorectal cancer and their matched normal mucosa. Methylation-specific PCR (MSP) was applied to evaluate the methylation status of 5'CpG island of IGFBP-rP1. Colon cancer cell lines LoVo and SW620 were treated with demethylation agent 5-aza-2'-deoxycytidine (5-aza-dC), followed by RT-PCR and MSP detection.</p><p><b>RESULTS</b>At the mRNA level, the expression of IGFBP-rP1 was higher in colorectal cancer tissue than that in the matched normal mucosa (P < 0.05). IGFBP-rP1 was methylated in 28/46 (60.9%) cases of colorectal cancer and 37/46 (80.4%) matched normal mucosa samples (P < 0.05). A negative correlation was found between IGFBP-rP1 expression and its methylation status. The expression of IGFBP-rP1 was restored in LoVo and SW620 after treatment with 5-aza-dC and MSP confirmation of its demethylation status. No relationships was found between the methylation status and clinicopathologic parameters.</p><p><b>CONCLUSIONS</b>IGFBP-rP1 expression is negatively correlated with its methylation status in colorectal cancer. DNA methylation is one of the mechanisms regulating the expression of IGFBP-rP1. Hypomethylation of IGFBP-rP1 gene with its overexpression plays an important role in the initiation and development of colorectal cancer.</p>

Biological effects and toxicology studies of melamine and its derivative cyanuric acid / 浙江大学学报·医学版

Melamine (Tripolycyanamide) and its derivatives have recently become a public concern on food safety. To better understand melamine and its major derivative cyanuric acid.literature on their chemical properties, metabolism, biological effects, relevant toxicology studies, and the detection methods is reviewed. Studies indicate that the acute toxicity of melamine and cyanuric acid is low. In mammalian, these compounds are hardly metabolized in vivo and are rapidly eliminated in the urine. When used in large dosage,these compounds demonstrate marked renal toxicity,as well as toxic effect towards heart. The renal toxicity is exemplified by the calculi formation, acute renal failure, and subsequently induced carcinomas of the urinary bladder. Among the tested species, male cats and rats are more prone to be affected by the compounds. The HPLC/MS/MS is becoming the mainstay of the detection methods. Despite of the achieved knowledge on melamine and cyanuric acid, further research is warranted to unveil the mechanism of underlying susceptibility of kidney, to develop better analytic methods,and to explore possible biomarkers for better clinical diagnosis.

Differential expression of secretagogin and glucose-related protein 78 in colorectal carcinoma: a proteome study / 中华病理学杂志

<p><b>OBJECTIVE</b>To identify the differentially expressed proteins or peptides and potential biomarkers of tumorigenesis for colorectal cancers.</p><p><b>METHODS</b>Immobilized pH gradient two-dimensional gel electrophoresis (2-DE) was used to separate and obtain the differentially expressed protein spots between colorectal cancers and matched normal mucosa. Liquid chromatography/mass spectrometry (LC-MS/MS) was used to characterize these proteins. Selected candidate proteins were further studied by Western blot, semi-quantitative RT-PCR and immunohistochemical staining.</p><p><b>RESULTS</b>Thirty-five protein spots showed marked expression changes (more than 5-fold) in colorectal carcinoma compared to normal mucosa. Fifteen proteins were up regulated and 20 were down regulated. Fourteen of these proteins were identified by tandem mass spectrometry, among which secretagogin (SCGN) was down-regulated and glucose-related protein (GRP) 78 was up-regulated in the tumors. The SCGN down-regulation was further supported by Western blot and RT-PCR analyses. Immunohistochemistry revealed that SCGN was strongly expressed in neuroendocrine cells of the colonic crypts and 53 of 54 (98%) neuroendocrine tumors. At protein level, although GRP78 was up regulated in colorectal carcinoma, there was no difference in the mRNA expression level between the tumor and paired normal mucosa.</p><p><b>CONCLUSIONS</b>The 2-DE combined with MS is a powerful tool for screening potential tumor biomarkers. The differentially expressed candidate proteins identified by 2-DE may be of significance in understanding the tumorigenesis of the colon cancer. SCGN is a potential biomarker for neuroendocrinal differentiation. GRP78 up-regulation in colorectal carcinomas may be related to its post-translational modification.</p>

Sclerosing angiomatoid nodular transformation of spleen / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features of sclerosing angiomatoid nodular transformation of spleen and its differential diagnosis.</p><p><b>METHODS</b>The clinicopathologic characteristics and immunophenotype of 4 cases of sclerosing angiomatoid nodular transformation of spleen were studied.</p><p><b>RESULTS</b>Histologically, all cases were characterized by multiple angiomatoid nodules of various sizes in a fibrosclerotic stroma. The nodules were round and sometimes convoluted. They were composed of slit-like, irregular-shaped or slightly dilated vascular spaces lined by plump endothelial cells and interspersed with a population of spindly or ovoid cells. Immunohistochemical study showed a heterogeneous staining pattern, with the lining cells of the small capillaries expressing CD34 and those of the sinusoid-like structures expressing CD8. CD31 highlighted both the lining cells and interspersed cells, resulting in a complex meshwork. The lining cells were also focally positive for CD68. Smooth muscle actin revealed conglomerates of spindly shaped cells around and between the vascular channels. These spindly shaped cells in the intervening stroma were focally positive for actin, but negative for desmin, CD21 and CD35.</p><p><b>CONCLUSIONS</b>Sclerosing angiomatoid nodular transformation is a rarely encountered benign lesion of the spleen, which should be distinguished from other angiomatoid tumors and tumor-like lesions.</p>

The correlation between polymorphisms of matrix metalloproteinase-2 and -9 genes and colorectal cancer of Chinese patients / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate whether the polymorphisms of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) promoters contribute to the development and progression of colorectal cancer in Chinese population.</p><p><b>METHODS</b>the PCR-based denaturing high-performance liquid chromatography or PCR-restriction fragment length polymorphism technique respectively was applied to analyze the MMP-2 -1306C/T and MMP-9 -1562C/T polymorphisms in normal group (126 individuals) and colorectal cancer group (126 cases). Genotype frequencies were compared between patients and matched controls, and the association of genotypes with clinical-pathological parameters was studied.</p><p><b>RESULTS</b>The frequency of the CC genotype in the MMP-2 gene polymorphism was significantly increased in colorectal cancer patients when compared with controls (P<0.05), and individuals with the CC genotype had an increased risk of developing colorectal cancer compared to those with CT+TT genotypes (OR: 1.959; 95%CI: 1.055-3.637). Significant correlation was found between the depth of tumor invasion and MMP-2 -1306C/T polymorphism in colorectal cancer patients. However, the genotype frequencies of MMP-9 -1562C/T in colorectal cancer patients were similar to those in control subjects.</p><p><b>CONCLUSION</b>Our results indicate that MMP-2 -1306 C/T polymorphism may be associated with genetic susceptibility to colorectal cancer and the invasive capability of colorectal cancer in Chinese patients. And it is easier for the CC genotype cancer to invade through bowel wall.</p>

Influence of clinical and pathomorphological parameters on prognosis in colon carcinoma and rectal carcinoma / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of clinical and pathomorphological parameters on the prognosis of colon carcinoma and rectal carcinoma.</p><p><b>METHODS</b>Univariate and multivariate COX proportional hazard models were used to study the effects of the clinical and pathomorphological factors on the prognosis in 101 cases of colon carcinoma, 219 of rectal carcinoma and 137 of rectal carcinoma under curative resections.</p><p><b>RESULT</b>By using univariate analysis, we identified that lymph node metastasis and distant metastasis were the common prognostic factors for both colon carcinoma and rectal carcinoma. Smoking, deep infiltration, chemotherapy and serum albumin concentration were the uncertain prognostic factors for colon carcinoma. Signet-ring cell carcinoma, larger tumor size (>6 cm), deep infiltration, lack of radical surgery, and advanced TNM stage were the exclusive adverse prognostic factors for rectal carcinoma. Further studies showed that the adverse prognostic factors for the rectal carcinoma under curative resection included deep infiltration, lymph node metastasis, vessel invasion, less of peritumoral lymphocyte infiltration, lack of Crohn's like reactivity, high level of tumor budding, advanced TNM stage and positive urine glucose. By using multivariate analysis based on a COX proportional hazard model, it was identified that smoking, lymph node metastasis and serum albumin concentration were independent prognostic factors for colon carcinoma; advanced TNM stage, distant metastasis and palliative surgery for rectal carcinoma; and vessel invasion, lymph node metastasis and urine glucose for rectal carcinoma under curative resections.</p><p><b>CONCLUSION</b>The various clinical and pathomorphological parameters show different prognostic value for colon carcinoma, rectal carcinoma and rectal carcinoma under curative resections.</p>

VNTR polymorphism of C6orf37 in Chinese population / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To identify a novel VNTR in C6orf37 and to detect the C6orf37 VNTR polymorphism distribution in Chinese population.</p><p><b>METHODS</b>RT-PCR and sequencing were conducted to identify VNTR alleles in the variable region of C6orf37.SSLP and DHPLC were applied in detecting the VNTR genotypes in 166 Chinese individuals.</p><p><b>RESULT</b>A novel VNTR sequence was found in the second exon of C6orf37, which was composed of 15 base pairs encoding 5-amino-acid (G-G-D-F-G). The repeat times ranged from 3 to 5. There were three common alleles containing three repeats (a), four repeats (b) and five repeats (c), respectively, which produced three homozygotes (a/a, b/b and c/c) and three heterozygotes (a/b, a/c and b/c). The frequency of a, b, c alleles were 0.145, 0.304, 0.551, respectively in Chinese population. Heterozygosity (H) was 0.583. Polymorphism information content (PIC) was 0.510. The screened result of DHPLC was consistent with that of SSLP.</p><p><b>CONCLUSION</b>A novel highly polymorphic VNTR in C6orf37 exists in Chinese population. DHPLC is the most efficient technique for screening VNTR polymorphism.</p>

IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis with its expression associated with DNA hypomethylation of exon 1 / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exon1. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2'-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the functional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony formation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1.

Anticancer effects of Chinese herbal medicine, science or myth? / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Currently there is considerable interest among oncologists to find anticancer drugs in Chinese herbal medicine (CHM). In the past, clinical data showed that some herbs possessed anticancer properties, but western scientists have doubted the scientific validity of CHM due to the lack of scientific evidence from their perspective. Recently there have been encouraging results, from a western perspective, in the cancer research field regarding the anticancer effects of CHM. Experiments showed that CHM played its anticancer role by inducing apoptosis and differentiation, enhancing the immune system, inhibiting angiogenesis, reversing multidrug resistance (MDR), etc. Clinical trials demonstrated that CHM could improve survival, increase tumor response, improve quality of life, or reduce chemotherapy toxicity, although much remained to be determined regarding the objective effects of CHM in human in the context of clinical trials. Interestingly, both laboratory experiments and clinical trials have demonstrated that when combined with chemotherapy, CHM could raise the efficacy level and lower toxic reactions. These facts raised the feasibility of the combination of herbal medicines and chemotherapy, although much remained to be investigated in this area.

Diagnostic accuracy and pitfalls in fine needle aspiration cytology of salivary glands: a study of 113 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To describe the fine needle aspiration cytology (FNAC) features of various salivary gland lesions and to analyze the respective diagnostic value and pitfalls.</p><p><b>METHODS</b>113 FNAC specimens of salivary gland lesions were reviewed and correlated with clinical and histopathologic findings.</p><p><b>RESULTS</b>The FNAC diagnostic failure (2); non-neoplastic lesions (12); benign neoplasm (82) and malignant neoplasm (17). Cytologically, the distinction between cellular pleomorphic adenoma, adenoid cystic carcinoma and basal cell adenoma could be difficult due to their overlapping morphologic features. The cytologic patterns of primary lymphoepithelial carcinoma of the parotid were indistinguishable from those of metastatic nasopharyngeal undifferentiated carcinoma. The ultimate distinction relied on clinical correlation. The three inaccurately diagnosed cases of FNAC are, as follows: reactive lymphoid hyperplasia of lymph node mistaken as non-Hodgkin lymphoma, mucoepidermoid carcinoma diagnosed as "scanty atypical cells present" and primary lymphoepithelial carcinoma mistaken as benign lymphoepithelial lesion. On the basis of FNAC, 97.4% (110 /113) were correctly depicted as benign (95/96; 99.0%) or malignant (15/17; 88.2%). Furthermore, 90.3% (102 /113) (specificity = 91.9%; 102/111) were accurately diagnosed, including 91.7% (88/96) benign lesions (specificity = 92.6% ; 88/95) and 82.4% (14/17) malignant tumors (specificity = 87.5%; 14/16).</p><p><b>CONCLUSIONS</b>FNAC is reliable in distinguishing benign and malignant salivary gland lesions. A specific cytologic diagnosis is often possible. On the other hand, due to the pitfalls in cytologic diagnosis of certain salivary gland tumors, tissue biopsy for histologic examination may be necessary.</p>

Study on independent factors on the prognosis of colorectal carcinoma: TNM stage, tumor budding, perineural invasion, peritumoral-lymphocytic infiltration and urine glucose / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the influence of clinical and pathological-morphological parameters on the prognosis of colorectal carcinoma.</p><p><b>METHODS</b>Univariate and multivariate Cox proportional hazard model were used to study the influence of clinical and pathological-morphological factors on the prognosis in 226 colorectal carcinoma cases.</p><p><b>RESULTS</b>Using univariate analysis, data showed that the factors significantly related to disease prognosis would include: the depth of direct spread, vessel invasion, perineural invasion, tumor budding, peritumoral-lymphocytic infiltration, Crohn-like reaction, number of positive lymph nodes, distant metastasis, TNM stage and urine glucose. Multivariate Cox proportional hazard model showed that six factors were identified to be associated with higher relative-risk (RR), including: older age, advanced TNM stage, more severe budding, perineural invasion, less peritumoral-lymphocytic infiltration and urine glucose.</p><p><b>CONCLUSION</b>Age, TNM stage, tumor budding, perineural invasive, peritumoral-lymphocytic infiltration and urine glucose were independent predictors to the prognosis of colorectal carcinoma.</p>

Germline polymorphisms of Bat26 and its significance in gastric cancer microsatellite instability / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To detect the germline polymorphic variations of Bat26 in Chinese and its significance in microsatellite instability (MSI) study of gastric cancers.</p><p><b>METHODS</b>Bat26 was analyzed by PCR-based denatured polyacrymide gel electrophoresis-silver stain method in peripheral blood from 389 healthy people and 34 gastric cancers with matched normal mucosa. Eleven other microsatellite loci were also detected for gastric cancers.</p><p><b>RESULT</b>(1) No Bat26 variations were identified in 423 genomic DNA from peripheral blood or normal mucosa by polyacrymide gel electrophoresis. (2) Two MSI-H cancers, oth Bat26+, were detected in 34 cases of gastric cancer. The alterations of Bat26 and MSI-H status were identical (P<0.05). (3) Compared with those of RER-cancers, MSI-H (RER+)cancers showed more obvious infiltration of intraepithelial lymphocytes and peri-tumoral lymphocytes, and more pushing borders (P<0.05).</p><p><b>CONCLUSION</b>(1) The germline polymorphisms of Bat26 in Chinese people are quasimonomorphic. Thus, no matched genomic DNA is needed while Bat26 was selected for tumor MSI analysis. (2) Bat26 is an independent indicator of MSI-H gastric cancers with distinct clinicopathological features.</p>

Correlation of multiple primary lung cancer with bronchial and alveolar epithelial dysplasia / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the correlation of multiple primary lung cancer with bronchial epithelial dysplasia and atypical adenomatous hyperplasia of bronchiolo-alveolar epithelium.</p><p><b>METHODS</b>Careful pathological examinations were performed on 114 surgical specimens of primary lung carcinoma. The correlation of multiple primary lung cancer with bronchial epithelial dysplasia and atypical adenomatous hyperplasia of bronchiolo-alveolar epithelium was analyzed.</p><p><b>RESULTS</b>Of 114 cases of primary lung cancer,13 cases of multiple primary lung cancer (11.4 %) was identifiedìwhich consisted of 6 cases containing two primary bronchogenic carcinoma and 7 containing one bronchogenic carcinoma and one bronchiolo-alveolar carcinoma. The rate of multiple primary lung cancers was significantly higher in individuals with high grade bronchial epithelial dysplasia than in those with low grade dysplasia (r=0.238, P<0.05).</p><p><b>CONCLUSION</b>Bronchial and alveolar epithelial cells may develop malignancy synchronously or metachronously. The probability of developing multiple primary lung cancer will increase in the lungs with extensive and severe bronchial epithelial dysplasia.</p>

Transforming growth factor beta receptor II mutations in RER positive colorectal cancers / 中华病理学杂志

<p><b>OBJECTIVE</b>To detect alterations of microsatellite loci [transforming growth factor beta receptor II (TGF-betaRII)(A)(10), TGF-betaRII(GT)(3), hMSH3(A)(8), hMSH6(C)(8), Bax(G)(8), IGFIIR(G)(8), IGFIIR(CT)(3)] and point mutations of TGF-betaRII (TGF-betaRII 452/454, TGF-betaRII 533).</p><p><b>METHODS</b>PCR-SSLP, microdissection-PCR-SSLP, PCR-SSCP, clone sequencing and immunohistochemistry were used.</p><p><b>RESULTS</b>The mutation rate of TGF-betaRII(A)(10) in RER+ (replication error positive) colorectal carcinomas was 33% (3/9). Similar mutations were also observed in adenomas with severe dysplasia. No mutations at other microsatellite loci were found. RER+ colorectal cancers mainly occurred in male patients at a young age and were more common in the colon than in the rectum (P < 0.05).</p><p><b>CONCLUSIONS</b>RER+ colorectal cancers were found in young males and commonly located in the colon. A one third mutation rate in TGF-betaRII(A)(10) in these patients is lower than that observed in western populations, which may imply diverse pathways of carcinogenesis of RER+ colorectal carcinoma. TGF-betaRII(A)(10) mutation may play a role in the transforming process from an adenoma with severe dysplasia to a full blown carcinoma.</p>

Bioinformatics analysis to the differentially expressed genes of normal mucosa and carcinoma of colon / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To systemically analyze the differentially expressed genes from normal mucosa and carcinoma of colon obtained by SSH method.</p><p><b>METHODS</b>An automatic platform for the analysis of nucleotides based on Linux was constructed, and one of the three subtracted libraries from SSH (T -N) was systematically analyzed by this platform. Part of the results was verified by semi- quantity RT-PCR.</p><p><b>RESULT</b>The automatic platform for the analysis of nucleotides based on Linux was successfully constructed. There were 15 contigs from the subtracted T-N libraries, among which 2 had no match with known genes in the GenBank. The expressions of genes Homo Sapiens thymosin beta 4 (THY) and Homo Sapiens HbxAg transactivated protein 2 (XTP) had trends of increase with the progress of normal tissue-adenoma-adenocarcinoma when verified by semi- quantity RT-PCR.</p><p><b>CONCLUSION</b>Linux-based automatic platform provides an efficient way to systematically analyze the nucleotide sequences, which may be used in study on the mechanism of colorectal carcinogenesis.</p>

Structural features of GR6 gene and its expression in colorectal neoplasm / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To determine the characteristics of GR6 gene and putative GR6 protein, and to evaluate the expression of GR6 gene in colorectal cancer and normal mucosa.</p><p><b>METHODS</b>Bioinformatic software and databases were applied to analyze the characteristics of GR6 gene and putative GR6 protein. Semi-quantitative RT-PCR was used to detect the expression of GR6 gene in colorectal carcinoma, adenoma and normal mucosa.</p><p><b>RESULT</b>GR6 gene, encoding putative GR6 protein, consisted of 3 exons and contained 4 CpG islands by sequence analysis. It was predicted that putative GR6 protein included one protein kinase C phosphorylation site, one casein kinase II phosphorylation site, and three N-myristoylation sites. PSORT II software analysis predicted that putative GR6 protein was located in nucleus (reliability: 76.7%). At the level of mRNA, the expression of GR6 gene was high in normal mucosa, moderate in mucosa adjacent to cancer and adenoma tissue, low in colorectal carcinoma tissue. Significant differences were demonstrated between normal mucosa and adenoma (P<0.05), normal mucosa and carcinoma (P<0.01).</p><p><b>CONCLUSION</b>The putative GR6 protein, encoded by GR6 gene may predictably function as an important nuclear signal transduction molecule. Decreased expression of GR6 gene may play an important role in the initiation and promotion of colorectal neoplasia.</p>

Alterations of p53 gene and microsatellite instability in ulcerative colitis and ulcerative colitis-associated colorectal cancer / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To study the expression of p53 protein, incidence of p53 gene mutation and microsatellite instability in ulcerative colitis, dysplasia of colonic mucosa and ulcerative colitis-associated colorectal cancer.</p><p><b>METHODS</b>P53 protein expression was detected by immunohistochemistry in 70 specimens from 21 cases of ulcerative colitis and 25 colonic mucosa specimens from normal subjects. The specimens of ulcerative colitis were examined for the mutation in exon 5, 6, 7, 8 of p53 gene with microdissection-PCR-SSCP/HA-clone-sequencing technique and the alterations in 10 microsatellite loci with microdissection-PCR-SSLP-clone- sequencing technique.</p><p><b>RESULT</b>None of 25 normal specimens was p53-positive immunohistochemically, while 4/21 of ulcerative colitis specimens were p53-positive. P53- positive rate in inflammatory mucosa of ulcerative colitis specimens was 0/5, while that was 1/7, 2/7 and 1/2 in low-grade displasia (LGD), high-grade displasia (HGD) and carcinoma, respectively. The abnormal exons were detected by SSCP and confirmed by sequencing in 2 out of 21 cases: one was exon 6 in a case with carcinoma and the other was exon 8 in a HGD case; both had positive P53 expression. Two cases showed positive in Bat26 locus by SSLP: one was a LGD case, the other was a case of carcinoma, who also had abnormal exon 6 of p53 gene. Other 9 microsatellite loci, (TGF beta RII(A)(10), IGFIIR(G)(8), IGFIIR(CT)(5), TGF beta RII(GT)(3), BAX(G)(8), hMSH3(A)8, hMSH6(C)(8), TCF4(A)(9) and DPC4 (CA)(17)) were showed negative in all cases.</p><p><b>CONCLUSION</b>P53 gene mutations and microsatellite instability may be one of the mechanisms for higher risk of carcinogenesis in ulcerative colitis.</p>