Recombinant viral protein promotes apoptosis and suppresses invasion of ovarian adenocarcinoma cells by targeting α5β1 integrin to down‐regulate Akt and MMP‐2

Abstract

BACKGROUND AND PURPOSEAs prognosis for patients with metastatic ovarian cancer is generally poor, advances in treatment are needed. Here, we studied the mechanism of action of a recombinant viral capsid protein (rVP1) and explored its effect against ovarian tumour growth and metastasis in vivo. EXPERIMENTAL APPROACHThe human ovarian cancer cell line SKOV3 and BALB/cAnN-Foxn1 female nude mice were used. Effects of rVP1 on the viability, invasive ability, matrix metalloproteinase (MMP)-2 activity and cancer cell proliferation and metastasis were determined by cell proliferation assay, Matrigel invasion assay, gelatin zymographic analysis, as well as bioluminescence imaging and immunohistological analysis in xenograft mouse models respectively. Levels of total and phosphorylated focal adhesion kinase (FAK), PKB/Akt, phosphatase and tensin homologue (PTEN) and glycogen synthase kinase-3b (GSK-3b) were detected by Western blotting. KEY RESULTSrVP1 promoted apoptosis and decreased invasion of human ovarian cancer cells. This effect of rVP1 was accompanied by activation of PTEN and GSK-3b as well as down-regulation of FAK, Akt and MMP-2. Anti-integrin antibodies or overexpression of constitutively active Akt reversed the cellular effects of rVP1. Orthotopic and intraperitoneal xenograft mouse models demonstrated that rVP1 attenuated survival and metastasis of human ovarian cancer SKOV3 cell line in vivo through selective regulation of Akt and GSK-3b activity as shown by bioluminescence imaging of mice and immunohistochemical analysis. CONCLUSION AND IMPLICATIONSThese results indicate that negative regulation of Akt signalling and MMP-2 by rVP1 may have the potential to suppress ovarian tumour growth and metastasis in vivo. AbbreviationsFAK, focal adhesion kinase; FMDV, foot-and-mouth disease virus; GFP, green fluorescent protein; GSK-3b, glycogen synthase kinase-3b; H&E, hematoxylin and eosin; PTEN, phosphatase and tensin homologue; rVP1, recombinant viral capsid protein BJP British Journal of Pharmacology

MIG-7 Controls COX-2/PGE2-Mediated Lung Cancer Metastasis

“…Metastatic progression was monitored weekly and quantified using a noninvasive bioluminescence In Vivo Imaging System (IVIS) (Xenogen) as described previously (22). Thirty-five days after injection, 3 mice were killed for necropsy and the other 6 mice were kept for survival studies.…”

“…Immunohistochemistry and histopathology analyses were conducted as described previously (22,24). The images were scanned into a digital format by Scanscope XT system (Aperio Technologies) and analyzed using Aperio ImageScope 9.1 software (Aperio Technologies).…”

“…Preparation of pCMV-GFP/luciferase-lentivirus and establishment of stable cell lines A549 GL cells were produced by infecting A549 cells with cytomegalovirus promoter (pCMV)-GFP/luciferase-lentivirus as described previously (22). A549 GL cells were then transfected with pcDNA6/BioEase-DEST (empty vector; EV) or pMIG7 plasmids and then selected with blasticidin (100 mg/mL) to produce A549…”

“…Gelatinolytic activities of MMP-2 and MMP-9, immunoprecipitation, and immunoblotting were conducted as described previously (21,22).…”

Autophagy-mediated regulation of macrophages and its applications for cancer

“…44 Furthermore, rVP1 also acts on host immune cells and promotes macrophage migration by inducing autophagy in these cells. 45 Mechanistic studies suggested that the phosphorylation levels of MAPK3/ ERK1 and MAPK1/ERK2 and the activity of MMP9 (matrix metalloproteinase 9 [gelatinase B, 92 kDa gelatinase, 92 kDa type IV collagenase]) are increased upon rVP1 treatment, leading to autophagy upregulation and macrophage migration by a mechanism dependent on WIPI1 (WD repeat domain, phosphoinositide interacting 1), WIPI2, ATG5, and ATG7, but not on BECN1.…”