P2Y2 nucleotide receptor-mediated extracellular signal-regulated kinases and protein kinase C activation induces the invasion of highly metastatic breast cancer cells

Abstract

Tumor metastasis is considered the main cause of mortality in cancer patients, thus it is important to investigate the differences between high- and low-metastatic cancer cells. Our previous study showed that the highly metastatic breast cancer cell line MDA-MB-231 released higher levels of ATP and exhibited higher P2Y2R activity compared with the low-metastatic breast cancer cell line MCF-7. In addition, P2Y2R activation by ATP released from MDA-MB-231 cells induced hypoxia-inducible factor-1α expression, lysyl oxidase secretion and collagen crosslinking, generating a receptive microenvironment for pre-metastatic niche formation. Thus, in the present study, we investigated which P2Y2R-related signaling pathways are involved in the invasion of breast cancer cells. The highly metastatic breast cancer cells MDA-MB-231 and SK-BR-3 showed higher invasion than MCF-7 and T47D cells at a basal level, which was abolished through P2Y2R knockdown or in the presence of apyrase, an enzyme that hydrolyzes extracellular nucleotides. MDA-MB-231 cells also showed high levels of mesenchymal markers, such as Snail, Vimentin and N-cadherin, but not the epithelial marker E-cadherin and this expression was inhibited through ATP degradation or P2Y2R knockdown. Moreover, SK-BR-3 and MDA-MB231 cells exhibited higher ERK and PKC phosphorylation levels than T47D and MCF-7 cells and upregulated phospho-ERK and -PKC levels in MDA-MB-231 cells were significantly downregulated by apyrase or P2Y2R knockdown. Specific inhibitors of ERK, PKC and PLC markedly reduced the invasion and levels of mesenchymal marker expression in MDA-MB-231 cells. These results suggest that over-activated ERK and PKC pathways are involved in the P2Y2R-mediated invasion of breast cancer cells.

Nucleotides and nucleoside signaling in the regulation of the epithelium to mesenchymal transition (EMT)

“…This action promoted a relocation of E-cadherin to cellular junctions, strongly suggesting that dephosphorylated metabolites of ATP participate in the control of EMT induction [89]. The increment in invasiveness, together with the downregulation of epithelial markers and the expression of mesenchymal markers mediated by the P2Y2 receptor, was also demonstrated in a highly metastatic breast cancer cellular line named MDA-MB-231, through a pathway mediated by PKC activity [90].…”

The dual mTOR kinase inhibitor TAK228 inhibits tumorigenicity and enhances radiosensitization in diffuse intrinsic pontine glioma

“…Invasion is also regulated by both mTORC1 and mTORC2 [45; 46; 47; 48; 49]. TAK228 treatment at 10 nM decreased invading cells in a Boyden matrigel transwell chamber assay by approximately 80% compared to DMSO in both SU-DIPG-XIII and JHH DIPG1 (p<0.0001 vs DMSO control) (Fig.…”

“…Meanwhile, multiple pro-invasion genes downstream of mTORC1 and mTORC2 are associated with metastasis in breast cancer [46; 48; 49], hepatocellular carcinoma [45; 52], and melanoma [47]. Furthermore, mTORC2, like mTORC1, is known to regulate cell growth through MYC activation [53].…”

P2Y 2 Nucleotide Receptor Prompts Human Cardiac Progenitor Cell Activation by Modulating Hippo Signaling

“…In addition, hCPC stimulation with UTP activated ERK1/2 (Online Figure X), a canonical inducer of cell proliferation and migration 34 that is known to crosstalk with both P2Y 2 R 35–38 and YAP signaling pathways 39–42 .…”