Anti-GPR75 monoclonal antibody, clone 790806

Purpose: Recent studies have shown that 20-hydroxyeicosatetraenoic acid (20-HETE) is a key molecule in sustaining androgen-mediated prostate cancer cell survival. Thus, the aim of this study was to determine whether 20-HETE can affect the metastatic potential of androgen-insensitive prostate cancer cells, and the implication of the newly described 20-HETE receptor, GPR75, in mediating these effects. Methods: The expression of GPR75, protein phosphorylation, actin polymerization and protein distribution were assessed by western blot and/or fluorescence microscopy. Additionally, in vitro assays including epithelial-mesenchymal transition (EMT), metalloproteinase-2 (MMP-2) activity, scratch wound healing, transwell invasion and soft agar colony formation were used to evaluate the effects of 20-HETE agonists/antagonists or GPR75 gene silencing on the aggressive features of PC-3 cells. Results: 20-HETE (0.1 nM) promoted the acquisition of a mesenchymal phenotype by increasing EMT, the release of MMP-2, cell migration and invasion, actin stress fiber formation and anchorage-independent growth. Also, 20-HETE augmented the expression of HIC-5, the phosphorylation of EGFR, NF-kappa B, AKT and p-38 and the intracellular redistribution of p-AKT and PKC alpha. These effects were impaired by GPR75 antagonism and/or silencing. Accordingly, the inhibition of 20-HETE formation with N-hydroxy-N'-(4-n-butyl-2-methylphenyl) formamidine (HET0016) elicited the opposite effects. Conclusions: The present results show for the first time the involvement of the 20-HETE-GPR75 receptor in the activation of intracellular signaling known to be stimulated in cell malignant transformations leading to the differentiation of PC-3 cells towards a more aggressive phenotype. Targeting the 20-HETE/GPR75 pathway is a promising and novel approach to interfere with prostate tumor cell malignant progression.

Lung cancer remains the leading cause of cancer death. DNA methylation plays an essential role in carcinogenesis through regulating gene expression and gene alternative splicing. However, the role of methylation in the tumorigenesis of lung squamous cell carcinoma (SCC) and its association with prognosis remains unclear. Here, we used an integrative approach to evaluate the prognostic value of epigenetic processes in lung SCC by examining the data provided by The Cancer Genome Atlas (TCGA). We found that the mean methylation level was significantly decreased in lung SCC. We also identified methylation-driven genes which were associated with cancer-related pathways. The multivariate Cox regression analysis showed four methylation-driven genes, GCSAM, GPR75, NHLRC1, and TRIM58, could be served as prognostic indicators for lung SCC. Validation on two external GEO datasets showed consistent methylation alterations of the four genes. These findings may have important implications in the understanding of the potential therapeutic method for lung SCC.