Transient receptor potential melastatin-related 7 channel is overexpressed in human pancreatic ductal adenocarcinomas and regulates human pancreatic cancer cell migration

• Published in: International journal of cancer Vol. 131; no. 6; pp. E851 - E861
• Main Authors: Rybarczyk, Pierre, Gautier, Mathieu, Hague, Frédéric, Dhennin-Duthille, Isabelle, Chatelain, Denis, Kerr-Conte, Julie, Pattou, François, Regimbeau, Jean-Marc, Sevestre, Henri, Ouadid-Ahidouch, Halima
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.09.2012; Wiley Subscription Services, Inc; Wiley
• Subjects: Adenocarcinoma - chemistry; Adenocarcinoma - metabolism; Adenocarcinoma - pathology; Biomarkers; Calcium - metabolism; Cancer; Carcinoma, Pancreatic Ductal - chemistry; Carcinoma, Pancreatic Ductal - metabolism; Carcinoma, Pancreatic Ductal - pathology; Cell adhesion & migration; Cell Line, Tumor; cell migration; Cell Movement; Humans; Life Sciences; magnesium; Magnesium - metabolism; Medical research; Pancreatic cancer; Pancreatic Neoplasms - chemistry; Pancreatic Neoplasms - metabolism; Pancreatic Neoplasms - pathology; Protein-Serine-Threonine Kinases; TRPM Cation Channels - analysis; TRPM Cation Channels - physiology; TRPM7
• ISSN: 0020-7136; 1097-0215
• DOI: 10.1002/ijc.27487

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive forms of cancer with a tendency to invade surrounding healthy tissues, leading to a largely incurable disease. Despite many advances in modern medicine, there is still a lack of early biomarkers as well as efficient therapeutical strategies. The melastatin‐related transient receptor potential 7 channel (TRPM7) is a nonselective cation channel that is involved in maintaining Ca2+ and Mg2+ homeostasis. It has been recently reported to regulate cell differentiation, proliferation and migration. However, the role of TRPM7 in PDAC progression is far to be understood. In our study, we show that TRPM7 is 13‐fold overexpressed in cancer tissues compared to the healthy ones. Furthermore, TRPM7 staining is stronger in tumors with high grade, suggesting a correlation between TRPM7 expression and PDAC progression. Importantly, TRPM7 expression is inversely related to patient survival. In BxPC‐3 cell line, dialyzing the cytoplasm during the patch‐clamp whole‐cell recording with a 0‐Mg2+ solution activated a nonselective current with a strong outward rectification. This cation current is inhibited by intracellular Mg2+ and by TRPM7 silencing. The downregulation of TRPM7 by small interference RNA dramatically inhibited intracellular Mg2+ fluorescence and cell migration without affecting cell proliferation, suggesting that TRPM7 contributes to Mg2+ entry and cell migration. Moreover, external Mg2+ following TRPM7 silencing fully restored the cell migration. In summary, our results indicate that TRPM7 is involved in the BxPC‐3 cell migration via a Mg2+‐dependent mechanism and may be a potential biomarker of poor prognosis of PDAC.