Functional expression of the transient receptor potential ankyrin type 1 channel in pancreatic adenocarcinoma cells

The transient receptor potential ankyrin type 1 (TRPA1) channel belongs to the TRP superfamily of ion channels. TRPA1 is a membrane protein with multiple functions able to respond to noxious stimuli, reactive oxygen species, inflammatory cytokines or pungent substances, and it participates in pain signalling, taste, inflammation and various steps of the tumorigenic process. To date, no reports have addressed the expression and function of TRPA1 in pancreatic ductal adenocarcinoma (PDAC) cells. This work reports the endogenous expression of TRPA1 channels in human pancreatic adenocarcinoma cell lines and provides insights into the function of the TRPA1 protein in the Panc-1 cell line. This study reports that cell lines isolated from PDAC patients had different levels of TRPA1 expression. The channel activity in Panc-1 cells, as assessed with electrophysiological (whole-cell patch clamp) and microfluorimetry methods, showed that non-selective cationic currents were activated by allyl isothiocyanate (AITC) in Panc-1 cells and inhibited by the selective TRPA1 antagonist A-967079. The current elicited by the specific agonist was associated with a robust increase in intracellular Ca2+. Furthermore, siRNA-induced downregulation of TRPA1 enhanced cell migration in the wound healing assay, indicating a possible role of ion channels independent from pore function. Finally, TRPA1 activation changed the cell cycle progression. Taken together, these results support the idea of channel-dependent and independent role for TRPA1 in tumoral processes.

Automated summary

This study reveals the endogenous expression of TRPA1 channels in human pancreatic adenocarcinoma cell lines and provides insights into the function of the TRPA1 protein, showing that different cell lines isolated from PDAC patients had varying levels of TRPA1 expression. Activation of TRPA1 by AITC in Panc-1 cells induced non-selective cationic currents, inhibited by the TRPA1 antagonist A-967079, and led to increased intracellular Ca2+ levels. siRNA-induced downregulation of TRPA1 enhanced cell migration, suggesting a role of ion channels independent of pore function, and TRPA1 activation altered cell cycle progression.