Microdissection and SAGE as a combined tool to reveal gene expression in ductal carcinoma in situ of the breast

TMEM158 promotes pancreatic cancer aggressiveness by activation of TGFβ1 and PI3K/AKT signaling pathway

Pancreatic cancer (PC) is one of the most deadly digestive cancers world-wide, with a dismal five-year survival rate of <8%. Upregulation of transmembrane protein 158 (TMEM158) is known to facilitate the progression of several carcinomas. However, little is known concerning the potential roles of TMEM158 in PC. Herein, we first found that TMEM158 was significantly upregulated in PC samples as well as PC cell lines. The overexpression of TMEM158 was significantly correlated with advanced clinicopathologic features (including tumor size, TNM stage, and blood vessel invasion) and poorer prognosis of patients with PC in clinic. Evidenced based on a series of loss- and gain-of-function assays uncovered that TMEM158 enhanced PC cell proliferation, migration, and invasion by stimulating the progression of cell cycle, epithelial-mesenchymal transition, and MMP-2/9 production. Furthermore, mechanism-related investigations disclosed that activation of TGFβ1 and PI3K/AKT signal might be responsible for TMEM158-triggered PC aggressiveness. Collectively, TMEM158 was upregulated in PC and promoted PC cell proliferation, migration, and invasion through the activation of TGFβ1 and PI3K/AKT signaling pathways, highlighting its potential as a tumor promoter and a therapeutic target for PC.

Silencing of TMEM158 Inhibits Tumorigenesis and Multidrug Resistance in Colorectal Cancer

Transmembrane protein 158 (TMEM158) plays pivotal roles in many cancers, including colorectal cancer (CRC). It has been reported that it is a recently identified upregulated gene during Ras-induced senescence. However, the clinical significance and biological functions of TMEM158 in CRC remain largely unknown. In this study, we found that TMEM158 was highly expressed in CRC tissues and cell lines compared with the corresponding noncancerous samples and normal colon epithelial cells. In vitro studies showed that TMEM158 silencing inhibited proliferation, and migration and increased apoptosis of CRC cells, whereas overexpression of TMEM158 increased proliferation, migration, and apoptosis escape of CRC cells. Mechanically, the levels of drug resistance-associated molecules, including multidrug resistance 1 and multidrug resistance protein 1, as well as the expression of antiapoptotic Bcl-2 were significantly upregulated. In addition, TMEM158 knockdown significantly inhibited tumor growth in vivo. Collectively, these results demonstrated that TMEM158 is a significant regulator of tumorigenesis and drug resistance in CRC and provided evidence that TMEM158 may be a promising target for CRC therapy.

Overexpression of TMEM158 contributes to ovarian carcinogenesis

Background

Transmembrane protein 158 (TMEM158) is a recently identified upregulated gene during Ras-induced senescence. Its association with various cancers has been recently reported. However, the expression and biological function of TMEM158 in ovarian cancer is still unclear. This study was aimed to elucidate the roles of TMEM158 in cell proliferation, adhesion and cell invasion of ovarian cancer cells.

Methods

We analyzed TMEM158 mRNA level in ovarian cancer tissues and adjacent no-tumorous tissues by real-time PCR. We then suppressed TMEM158 expression of ovarian cancer cells by RNA interference and examined the effects of TMEM158 knockdown on cancerous transformation of ovarian cancer cells.

Results

The RNA-sequencing data of the ovarian cancer cohort from The Cancer Genome Atlas project (TCGA) and our real-time PCR data showed that TMEM158 was overexpressed in ovarian cancer. Knockdown of TMEM158 by RNA interference in ovarian cancer cells significantly inhibited cell proliferation, which may be due to the increase of G1-phase arrest. Silencing of TMEM158 also inhibited cell adhesion, cell invasion as well as tumorigenicity in nude mice. Moreover, knockdown of TMEM158 notably repressed cell adhesion via down-regulating the expression intercellular adhesion molecule1 (ICAM1) and vascular cell adhesion molecule1 (VCAM1). Transforming Growth Factor-β (TGF-β) signaling pathway was also remarkably impaired by TMEM158 silencing.

Conclusions

Our data suggests that TMEM158 may work as an oncogene for ovarian cancer and that inhibition of TMEM158 may be a therapeutic strategy for ovarian cancer.

Laser-assisted microdissection in translational research: theory, technical considerations, and future applications

Molecular profiling already exerts a profound influence on biomedical research and disease management. Microdissection technologies contribute to the molecular profiling of diseases, enabling investigators to probe genetic characteristics and dissect functional physiology within specific cell populations. Laser-capture microdissection (LCM), in particular, permits collation of genetic, epigenetic, and gene expression differences between normal, premalignant, and malignant cell populations. Its selectivity for specific cell populations promises to greatly improve the diagnosis and management of many human diseases. LCM has been extensively used in cancer research, contributing to the understanding of tumor biology by mutation detection, clonality analysis, epigenetic alteration assessment, gene expression profiling, proteomics, and metabolomics. In this review, we focus on LCM applications for DNA, RNA, and protein analysis in specific cell types and on commercially available LCM platforms. These analyses could clinically be used as aids to cancer diagnosis, clinical management, genomic profile studies, and targeted therapy. In this review, we also discuss the technical details of tissue preparation, analytical yields, tissue selection, and selected applications using LCM.

The oestrogen-dependent biology of breast cancer. Sensitivity and resistance to aromatase inhibitors revisited: a molecular perspective

Endocrine treatment of breast cancer was the first molecular targeted anti-cancer therapy to reach clinical practice. Among the several options that share the common denomination of hormonal treatment, aromatase inhibitors (AIs) in the postmenopausal setting show the highest efficacy rates. These drugs have become the standard of care both in the advanced and adjuvant scenarios. Nevertheless resistance to AIs either upfront or after initial clinical response is almost a universal feature whenever tumour excision is not possible. Multiple reports have established the role of alternative pro-growth signalling pathways in the acquisition of resistance to the oestradiol deprivation that AIs produce. However the first clinical trials addressing the double blockade of both the oestrogen and other growing factor pathways raise some concerns on the efficacy of this approach. This review presents the evidence on the molecular events underpinning the response and resistance to AIs and suggests some key issues to consider when designing clinical research projects in this context.

Transcriptome analysis of serous ovarian cancers identifies differentially expressed chromosome 3 genes

Cytogenetic, molecular genetic and functional analyses have implicated chromosome 3 genes in epithelial ovarian cancers (EOC). To further characterize their contribution to EOC, the Affymetrix U133A GeneChip(R) was used to perform transcriptome analyses of chromosome 3 genes in primary cultures of normal ovarian surface epithelial (NOSE) cells (n = 14), malignant serous epithelial ovarian tumors (TOV) (n = 17), and four EOC cell lines (TOV-81D, TOV-112D, TOV-21G, and OV-90). A two-way comparative analysis of 735 known genes and expressed sequences identified 278 differentially expressed genes, where 43 genes were differentially expressed in at least 50% of the TOV samples. Three genes, RIS1 (at 3p21.31), GBE1 (at 3p12.2), and HEG1 (at 3q21.2), were similarly underexpressed in all TOV samples. Deregulation of the expression of these genes was not associated with loss of heterozygosity (LOH) of the genetic loci harboring them. LOH analysis of the RIS1, GBE1, and HEG1 loci was observed at frequencies of 14.3%, 13.7%, and 9.2%, respectively, in a series of 66 malignant TOV samples of the serous subtype. Reduced expression levels of RIS1, GBE1, and HEG1 were observed only in the tumorigenic EOC cell lines (TOV-21G, TOV-112D, and OV-90) and did not correlate with LOH. These results combined suggest that RIS1, GBE1, and HEG1, unlike classical tumor suppressor genes, are not likely to be primary targets of inactivation. This study provides a comprehensive analysis of chromosome 3 gene expression in NOSE and in EOC samples and identifies chromosome 3 gene candidates for further study.