Showing papers by "Weiqi Sheng published in 2011"

MicroRNA-95 promotes cell proliferation and targets sorting Nexin 1 in human colorectal carcinoma.

Abstract: MicroRNAs (miRNAs) are strongly implicated in cancer but their specific roles and functions in the major cancers have yet to be fully elucidated. In this study, we defined the oncogenic significance and function of miR-95, which we found to be elevated in colorectal cancer (CRC) tissues by microarray analysis. Evaluation of an expanded CRC cohort revealed that miR-95 expression was up-regulated in nearly half of the tumors examined (42/87) compared with the corresponding noncancerous tissues. Ectopic overexpression of miR-95 in human CRC cell lines promoted cell growth in vitro and tumorigenicity in vivo, whereas RNAi-mediated silencing of miR-95 decreased cell growth ratio. Mechanistic studies revealed that miR-95 repressed the expression of reporter gene coupled to the 3'-untranslated region of sorting nexin 1 (SNX1), whereas miR-95 silencing up-regulated SNX1 expression. Moreover, miR-95 expression levels correlated inversely with SNX1 protein levels in human CRC tissues. RNAi-mediated knockdown of SNX1 phenocopied the proliferation-promoting effect of miR-95, whereas overexpression of SNX1 blocked miR-95-induced proliferation of CRC cells. Taken together, these results demonstrated that miR-95 increases proliferation by directly targeting SNX1, defining miR-95 as a new oncogenic miRNA in CRC.

Perineural invasion in pT3N0 rectal cancer: the incidence and its prognostic effect.

Abstract: BACKGROUND: The authors' purpose was to explore the incidence and prognostic significance of perineural invasion (PNI) in pT3N0 rectal cancer. METHODS: Pathologic materials from resected specimens of 173 patients with pT3N0 rectal cancer were retrospectively collected. PNI-positivity was categorized into 2 groups: surrounding the nerve sheath (SS-PNI) and invading through the nerve sheath (TS-PNI). The rate of PNI-positivity was compared with PNI as initially recorded in the original reports. Patients' outcome was studied in groups with different PNI status, and multivariate analysis was performed to determine its prognostic value. RESULTS: In this retrospective analysis, PNI-positivity was found in 24.3% of all cases, in which SS-PNI and TS-PNI were 11% and 13.3%, respectively, and was related to lymphovascular invasion. Only 7.5% of patients' specimens were reported as PNI-positive in the original reports. Detection of SS-PNI was likelier to be missed than TS-PNI. The rates of local recurrence, disease-free survival, and overall survival at 5 years were similar between the groups of SS-PNI and TS-PNI. The 5-year local recurrence rate was more than 2.5-fold higher in the PNI-positive group compared with the PNI-negative group (22.7% vs 7.9%, respectively; P = .017). Multivariate analysis proved that PNI-positivity was the only independent risk factor for predicting 5-year local recurrence rate, whereas only sampled lymph nodes was related to 5-year disease-free survival and overall survival. CONCLUSIONS: PNI is a common pathologic feature in rectal cancer. The definition of PNI should include SS-PNI and TS-PNI. Rectal cancer patients who are PNI-positive are at higher risk of local recurrence and should be considered for more intensive treatment. Cancer 2011. © 2010 American Cancer Society.

Distinct mutations in MLH1 and MSH2 genes in hereditary non-polyposis colorectal cancer (HNPCC) families from China.

Abstract: Hereditary non-polyposis Colorectal Cancer (HNPCC) is an autosomal dominant inheritance syndrome. HNPCC is the most common hereditary variant of colorectal cancer (CRC), which accounts for 2-5% CRCs, mainly due to hMLH1 and hMSH2 mutations that impair DNA repair functions. Our study aimed to identify the patterns of hMSH2 and hMLH1 mutations in Chinese HNPCC patients. Ninety-eight unrelated families from China meeting Amsterdam or Bethesda criteria were included in our study. Germline mutations in MLH1 and MSH2 genes, located in the exons and the splice-site junctions, were screened in the 98 probands by direct sequencing. Eleven mutations were found in ten patients (11%), with six in MLH1 (54.5%) and five in MSH2 (45.5%) genes. One patient had mutations in both MLH1 and MSH2 genes. Three novel mutations in MLH1 gene (c.157_160delGAGG, c.2157dupT and c.-64G>T) were found for the first time, and one suspected hotspot in MSH2 (c.1168C>T) was revealed.

Myoid harmatoma of the breast: clinicopathologic analysis of a rare tumor indicating occasional recurrence potential.

Abstract: To the Editor: Myoid hamartoma (MH) is an extremely rare subtype of breast hamartoma characterized by the presence of myoid cell bundles in the stroma. Only approximately 30 cases have been reported to date. So its biological behavior, clinicopathologic features and histological origin are not well characterized. Moreover, its potential recurrence is usually overlooked. To the best of our knowledge, no case of MH with local recurrence has been reported previously. Herein, we described clinicopathologic features of five MHs, containing two recurrent lesions. Our aim is to elucidate pathologic features of MH, and to lay stress on its recurrence potential to evoke attentions of pathologists and surgeons. Five cases of MH were collected in the Department of Pathology, Shanghai Cancer Center, Fudan University, Shanghai. For each case, sections of 5 lm were cut from paraffin blocks for HE and immunohistochemistry using Envision method. The primary antibodies included vimentin, desmin, h-caldesmon, calponin, SMA, MSA. One case was studied ultrastructurally. The age of five patients ranged from 29 to 44 years (mean, 39 years). Physical examinations all revealed nontender, palpable lumps. The radiological information of two patients was available. On Mammography, two lesions appeared as ovoid to rounded, well circumscribed masses of mixed heterogenous density. A thin smooth capsule with peripheral radiolucent zone was seen in one lesion. In MRI, the lesion displayed an ovoid, well-defined mass with heterogenous enhancement, a focal dark thin rim. Internal fat intensity was demonstrated. All patients underwent lumpectomy. Three patients were well after the initial surgery. However, two cases developed local recurrence. One case relapsed 10 months following the initial surgery. Another recurred twice, with an interval of 36 and 41 months, respectively. Moreover, when recurred for the second time there were two separate