Knockdown of Transient Receptor Potential Canonical-1 Reduces the Proliferation and Migration of Endothelial Progenitor Cells

Abstract

Endothelial progenitor cells (EPCs) play an important role in accelerating endothelial repair after vascular injury. The proliferation and migration of EPCs is a critical first step in restoring endothelial. However, mechanisms for modulating EPC proliferation and migration are still being elucidated. Our previous study found that transient receptor potential canonical-1 (TRPC1) is involved in regulating store-operated Ca 2 + entry in EPCs through stromal interaction molecule 1. Therefore, in the present study, we sought to further investigate the regulation of proliferation and migration of EPCs by TRPC1. We found that the silencing of TRPC1 by 2 different RNA interference methods suppressed the proliferation and migration of EPCs. In addition, knockdown of TRPC1 significantly reduced of the amplitude of store-operated Ca 2 + entry and caused arrest of the EPC cell cycle in G1 phase. Analysis of the expression of 84 cell cycle genes by microarray showed that 9 genes were upregulated and 4 were downregulated by > 2-fold in EPCs following TRPC1 silencing. The genes with expression changes were Ak1, Brca2, Camk2b, p21, Ddit3, Inha, Slfn1, Mdm2, Prm1, Bcl2, Mki67, Pmp22, and Ppp2r3a. Finally, we found that a Schlafen 1-blocking peptide partially reversed the abnormal cell cycle distribution and proliferation induced by TRPC1 knockdown, suggesting that Schlafen 1 is downstream of TRPC1 silencing in regulating EPC proliferation. In summary, these findings provide a new mechanism for modulating the biological properties of EPCs and suggest that TRPC1 may be a new target for inducing vascular repair by EPCs.

Transient Receptor Potential Canonical 1 (TRPC1) Channels as Regulators of Sphingolipid and VEGF Receptor Expression

“…We based this decision on the fact that previous studies have unambigously shown that TRPC1 is ubiquitously expressed in humans and is of physiological significance in regulating many cellular processes, including calcium signaling, cell proliferation, and migration, in both normal and cancer cells (5,6,8,9,37). Surprisingly, we observed that knockdown of TRPC1 did not affect SOCE but rather receptor-operated calcium entry.…”

“…Previous studies have shown that TRPC1 is ubiquitously expressed in humans and regulates many cellular processes, including cell proliferation and migration in both normal and cancer cells (5,6,8,9). To investigate the importance of the TRPC1 channel in thyroid cancer cells, we thus generated stable TRPC1 knockdown cells.…”

“…These channels participate in both receptor-operated calcium entry, as well as store-operated calcium entry (together with the STIM1 and Orai1 proteins). Of the TRPC channels, the TRPC1 channels are widely expressed in human tissues and are involved in regulation of many cellular processes, including cancer cell invasion, migration, and proliferation (5)(6)(7)(8). The structure of TRPC1 enables it to interact with other TRPC channels to form complexes and with adaptor proteins and signaling proteins like G-coupled receptor proteins, phospholipase C, and calcium regulatory proteins.…”

Functional properties of ion channels and transporters in tumour vascularization

“…HMEC, human microvascular EC; HPAEC, human pulmonary artery EC; HUVEC, human umbilical vein EC; EA.hy926, EC line derived from HUVEC fused with human lung adenocarcinoma cell line A549; PAEC, porcine aortic endothelial cells; BTEC, tumour-derived EC from breast carcinoma; H5VEC, heart endothelioma (H5V) EC; MAEC, mouse aortic EC; EPC, endothelial progenitor cells; RCC-EPC, EPC isolated from renal carcinoma patients; Numbers in parenthesis indicate the respective reference number. EPC [30] HMEC [31] BTEC [32] RCC-EPC [29] HUVEC [33 -35] HUVEC [36] HUVEC [37] HUVEC [38] HUVEC [36,39] MAEC from KO mice [40] HMEC [41,42] EPC [43] survival and proliferation RCC-EPC [29] EPC [30] HMEC [31] HUVEC [44] PAEC [45] H5V EC [46] HUVEC [40] HUVEC, HMEC [41,55] EPC [43] permeability HMEC,HUVEC [56 -58] HPAEC [59] Frog mesenteric microvessels [60] H5V EC [46] HUVEC [61] in vivo angiogenesis zebrafish [62] CAM [44] collateral growth [45] HERG-1-Retinoblastoma [63] EAG1-Xenograft in SCID mice and human osteosarcoma [27,28] CAM [54] xenograft in nude mice [38] Rabbit cornea [64] human mammary carcinoma, glioblastoma [65,66] AQP1 KO mice and C57BL/ 6 mice …”

Transient Receptor Potential Channel 1 Deficiency Impairs Host Defense and Proinflammatory Responses to Bacterial Infection by Regulating Protein Kinase Cα Signaling

“…Ca 2ϩ entry through receptor-mediated channels is essential for regulating cellular functions, and TRPC1, which functions as a nonselective cation channel in many cell types, has been shown to be important in Ca 2ϩ entry that is initiated by store depletion (7,9). In particular, TRPC1 is reportedly associated with cell proliferation, cell migration, enzyme and fluid secretion, normal metabolism in various organ systems, and cancer metastasis (6,10,11). TRPC1 could also form a heteromultimer with Orai1 and stromal interaction molecule 1 (STIM1), which are essential for Ca 2ϩ signaling (12)(13)(14).…”