Pokemon proto-oncogene in oral cancer: potential role in the early phase of tumorigenesis.

Oral squamous cell carcinoma (OSCC) represents about 90% of all oral neoplasms with a poor clinical prognosis. To improve survival of OSCC patients, it is fundamental to understand the basic molecular mechanisms characterizing oral carcinogenesis. Dysregulation of oncogenes and tumor suppressor genes seems to play a central role in tumorigenesis, including malignant transformation of the oral cavity. We analyzed the expression levels of the pro-oncogenic transcription factor Pokemon through real-time PCR, Western blot and immunohistochemistry in tumor, and normal oral tissue samples obtained from 22 patients with OSCC. The relationship between tumor characteristics and the level of Pokemon intratumor expression was also analyzed. Pokemon was significantly downregulated in OSCC. In particular, both mRNA and protein levels (tumor vs normal tissue) inversely correlated with histological grading, suggesting its potential role as a prognostic factor for OSCC. Moreover, a significant inverse correlation was found between Pokemon protein expression levels (OSCC vs normal oral mucosa) and tumor size, supporting the hypothesis that Pokemon could play an important role in the early phase of tumor expansion. This work shows that reduced expression of Pokemon is a peculiar feature of OSCC. Additional studies may establish the effective role of Pokemon in oral tumorigenesis.

Sartini D ，Lo Muzio L ，Morganti S ，Pozzi V ，Di Ruscio G ，Rocchetti R ，Rubini C ，Santarelli A ，Emanuelli M ... -  《-》

Parathyroid hormone-related protein serves as a prognostic indicator in oral squamous cell carcinoma.

Lv Z ，Wu X ，Cao W ，Shen Z ，Wang L ，Xie F ，Zhang J ，Ji T ，Yan M ，Chen W ... -  《JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH》

The role of E-cadherin down-regulation in oral cancer: CDH1 gene expression and epigenetic blockage.

Pannone G ，Santoro A ，Feola A ，Bufo P ，Papagerakis P ，Lo Muzio L ，Staibano S ，Ionna F ，Longo F ，Franco R ，Aquino G ，Contaldo M ，De Maria S ，Serpico R ，De Rosa A ，Rubini C ，Papagerakis S ，Giovane A ，Tombolini V ，Giordano A ，Caraglia M ，Di Domenico M ... -  《-》

Increased Expression of Tissue/Salivary Transgelin mRNA Predicts Poor Prognosis in Patients with Oral Squamous Cell Carcinoma (OSCC).

Bu J ，Bu X ，Liu B ，Chen F ，Chen P ... -  《MEDICAL SCIENCE MONITOR》

MicroRNA-186 serves as a tumor suppressor in oral squamous cell carcinoma by negatively regulating the protein tyrosine phosphatase SHP2 expression.

MicroRNAs (miRs) have been shown to play critical roles in the pathogenesis of oral squamous cell carcinoma (OSCC), the current study is designed to identify the potential role of miR-186 in OSCC. Realtime polymerase chain reaction was used to determine miR-186 expression in paired tissue samples (OSCC and adjacent normal tissues) and multiple oral cell lines (normal oral keratinocyte HOK cell and OSCC cell lines). Cell viability, colony formation and flow cytometry assays were used to assess the biological function of miR-186. Furthermore, luciferase and western blot assays were used to verify the predicted target of miR-186. We found that miR-186 expression was significantly downregulated in OSCC tissues and cell lines. Overexpression of miR-186 produced an anti-growth effect and induced apoptosis in Tca8113 and SCC-25 cells. Luciferase assay revealed that miR-186 directly targeted PTPN11 (a gene encodes the protein tyrosine phosphatase SHP2) mRNA 3' untranslated region and suppressed its expression. Consistently, MiR-186 and SHP2 were negatively correlated in OSCC tissues. Consequently, miR-186 inhibited signaling activities of Extracellular Regulated protein Kinases (ERK) and Protein kinase B (AKT), which act downstream of SHP2 and are critical for growth of cancer cells. We identify that miR-186 serves as a tumor suppressor in OSCC. Downregulation of this microRNA may lead to a higher expression of oncogenic factor SHP2, which leads to activation of growth promoting signaling. Thus, miR-186 may be a novel and effective therapeutic agent for the treatment of OSCC.

Cai Z ，Hao XY ，Liu FX 《-》