microRNA (miRNA) dysregulation contributes widely to human cancer but has not been fully assessed in oral cancers. In this study, we conducted a global microarray analysis of miRNA expression in 40 pairs of betel quid-associated oral squamous cell carcinoma (OSCC) specimens and their matched nontumorous epithelial counterparts. Eighty-four miRNAs were differentially expressed in the OSCC specimens compared with the matched tissue. Among these downregulated miRNAs, 19 miRNAs were found and mapped to the chromosome 14q32.2 miRNA cluster region, which resides within a parentally imprinted region designated as Dlk-Dio3 and known to be important in development and growth. Bioinformatic analysis predicted two miRNAs from the cluster region, miR329 and miR410, which could potentially target Wnt-7b, an activator of the Wnt-b-catenin pathway, thereby attenuating the Wnt-b-catenin signaling pathway in OSCC. Stable ectopic expression of Wnt-7b in OSCC cells overexpressing miR329 or miR410 restored proliferation and invasion capabilities abolished by these miRNA. Combining a demethylation agent and a histone deacetylase inhibitor was sufficient to reexpress miR329, miR410, and Meg3, consistent with epigenetic regulation of these miRNA in human OSCC. Specifically, arecoline, a major betel nut alkaloid, reduced miR329, miR410, and Meg3 gene expression. Overall, our results provide novel molecular insights into how betel quid contributes to oral carcinogenesis through epigenetic silencing of tumor-suppressor miRNA that targets Wnt-b-catenin signaling. Cancer Res; 74(24); 7560-72. Ó2014 AACR.
The results of this research suggest that the etiology of pyogenic granuloma is due to the imbalance between angiogenesis enhancers and inhibitors. Whether and how the angiogenesis-associated factors are regulated by female steroid hormones remain to be answered.
Approximately 30% of apparently Rh- Taiwanese people actually were RhD(el), a rare variant of the Rh system that might carry a grossly intact RHD gene. Several studies have indicated that the RhD(el) trait might be generated by multiple molecular mechanisms. In this study, a total of 294 Taiwanese serologically RhD- blood donors were tested for Rh phenotypes and RHD genotypes. Among them, total RHD deletion, partial RHD gene, and RhD(el) were found in 185 (62.9%), 15 (5.1%), and 94 (32.0%), respectively. The 1227A allele and exon 9 of the RHD gene were found in all 94 RhD(el) donors. The Ccee was the most prevalent phenotype in the RhD(el) group (78/94 [83%]), and the ccee phenotype was highly prevalent in the true D- group (87.6%). RHD 1227A can be used as an important and useful genetic marker for RhD(el). It can be detected easily by a simple, rapid, specific sequence primer-polymerase chain reaction method.
Sixty squamous cell carcinomas of tongue and buccal mucosa were examined for expression of p53 protein by using an immunohistochemical technique improved by an antigen retrieval method. Twenty-seven (45%) tumors demonstrated strongly positive staining. Thirteen of p53-positive tumors (48%) also exhibited overexpression of p53 in immediately adjoining hyperplastic or pre-malignant epithelium. All 22 metastatic lymph nodes and 18 local recurrent lesions (except two) had an identical p53 immunophenotype to their corresponding primary sites. Mitotic indices were significantly higher in p53-positive tumors (P < 0.01); however, no association of PCNA scores with p53 expression was found (P > 0.1). There was no correlation between p53 overexpression and tumor grade, size and staging, vascular invasion, lymph node metastasis, and early local recurrence. Overexpression of p53 was found to be relatively higher, although not statistically significant, in nonsmokers than in heavy smokers (66.7% vs. 42.9%), and in nonbetel-quid chewers than in heavy chewers (62.5% vs. 34.2%). These data are consistent with the hypothesis that inactivation of p53 protein may occur in the early phases of oral tumorigenesis. It may not be a useful prognostic marker but could possibly be used for risk assessment and surveillance of local recurrence.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.