DAMTC regulates cytoskeletal reorganization and cell motility in human lung adenocarcinoma cell line: an integrated proteomics and transcriptomics approach

Abstract

DAMTC (7,8-diacetoxy-4-methylcoumarin) is a thioderivative of 4-methyl coumarin, and previously we have shown that DAMTC is a potent inhibitor of cell growth and an inducer of apoptosis in non-small cell lung cancer (A549) cells. It induces apoptosis through mitochondrial pathway by modulating NF-κB, mitogen-activated protein kinase (MAPK) and p53 pathways. Herein, we explored the genome-wide effects of DAMTC in A549 cells using the concerted approach of transcriptomics and proteomics. In addition to apoptotic pathways, which have been validated earlier, the bioinformatic analysis of microarray data identified small GTPase-mediated signal transduction among the significantly altered biological processes. Interestingly, we observed significant downregulation of some members of the Rho family GTPases in the proteomics data too. Downregulation of Rho GTPases (RhoGDIα (Rho GDP dissociation inhibitor-α, also known as ARHGDIA), Ras homolog family member A, Ras-related C3 botulinum toxin substrate 1 and cell division cycle 42) was validated by western blotting. The Rho protein family is implicated in maintaining the actin filament assembly and cell motility, and we also observed that DAMTC treatment causes actin cytoskeletal reorganization, promotes filopodia formation and inhibits cell motility in A549 cells. The effect of DAMTC treatment on cytoskeleton was reversed after the overexpression of RhoGDIα. In addition, DAMTC augmented the apoptotic effect of etoposide, a proapoptotic chemotherapeutic drug. This elucidation of the mechanism behind DAMTC-induced apoptosis and inhibition of cell motility in A549 cells may make it a potential therapeutic for lung cancer.

Sj7170, a Unique Dual-function Peptide with a Specific α-Chymotrypsin Inhibitory Activity and a Potent Tumor-activating Effect from Scorpion Venom

“…9C). Small GTPases of the Rho-GTPase family (RhoA, Rac1, and Cdc42) are known to act directly on the cytoskeleton and are responsible for the development of membrane ruffles, stress fibers, lamellipodia, and filopodia (16). In this study, the protein levels of RhoA, Rac1, and Cdc42 were significantly increased in rSj7170-treated U87 cells, compared with the control U87 cells (Fig.…”

MicroRNA-195 inhibits proliferation, invasion and metastasis in breast cancer cells by targeting FASN, HMGCR, ACACA and CYP27B1

“…The wound area was monitored for the next 2 days at an interval of 24 h. The microscopy images of the cells migrating in the wound area were taken at 10× magnification by Nikon Eclipse Ti microscope (Nikon, Tokyo, Japan). The quantitative values of the wound size were determined by web-based WimScratch module of Wimasis online software 44 .…”

Pro-apoptotic miRNA-128-2 modulates ABCA1, ABCG1 and RXRα expression and cholesterol homeostasis

“…We performed western blotting as described 62 using untransfected and transfected cells (with p(128) and/or negative control and/or anti-miR-128 and/or SAM and/or SIRT1 siRNA and/or SIRT1 ORF) after 24 h of transfection. In brief, cells were trypsinized and lysed with modified RIPA buffer (50 mM Tris-HCl, pH 7.4, 150 mM NaCl, 1% NP40, 0.25% Na-deoxycholate, 1 mM EDTA) containing protease inhibitors (1  μ g/ml aprotinin, 1  μ gml leupeptin, 1  μ g/ml pepstatin, 1 mM PMSF, 1 mM sodium orthovanadate and 1 mM sodium fluoride) for 30 min on ice.…”