Reduction of metastatic potential by inhibiting EGFR/Akt/p38/ERK signaling pathway and epithelial-mesenchymal transition after carbon ion exposure is potentiated by PARP-1 inhibition in non-small-cell lung cancer

• Published in: BMC cancer Vol. 19; no. 1; p. 829
• Main Authors: Chowdhury, Priyanka, Dey, Payel, Ghosh, Sourav, Sarma, Asitikantha, Ghosh, Utpal
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 22.08.2019; BioMed Central; BMC
• Subjects: Biomarkers, Tumor; Cancer cells; Cancer metastasis; Cancer research; Carbon ion exposure; Carcinoma, Non-Small-Cell Lung - genetics; Carcinoma, Non-Small-Cell Lung - metabolism; Carcinoma, Non-Small-Cell Lung - pathology; Carcinoma, Non-Small-Cell Lung - therapy; Care and treatment; Cell Line, Tumor; Cell Movement; Cell Survival - genetics; Chemotherapy; Control; Epithelial-Mesenchymal Transition; Epithelial-mesenchymal transition (EMT); ErbB Receptors - metabolism; Extracellular Signal-Regulated MAP Kinases - metabolism; Gene Expression Regulation, Neoplastic; Genes; Humans; Lung cancer; Lung Neoplasms - drug therapy; Lung Neoplasms - genetics; Lung Neoplasms - metabolism; Lung Neoplasms - pathology; Matrix metalloproteinases (MMPs); Metastatic potential; Non-small cell lung cancer; p38 Mitogen-Activated Protein Kinases - metabolism; PARP-1; Patient outcomes; Poly (ADP-Ribose) Polymerase-1 - antagonists & inhibitors; Proteins; Proto-Oncogene Proteins c-akt - metabolism; Radiation Tolerance - drug effects; Radiation, Ionizing; Radiotherapy; Signal Transduction - drug effects; Small cell lung cancer; Stem cells; Tumor proteins; Wound care; Wound Healing; India; Matrix metalloproteinases (MMPs); Non-small-cell lung cancer; Metastatic potential; Carbon ion exposure; Epithelial-mesenchymal transition (EMT); PARP-1
• ISSN: 1471-2407; 1471-2407
• DOI: 10.1186/s12885-019-6015-4

Carbon ion ( C) radiotherapy is becoming very promising to kill highly metastatic cancer cells keeping adjacent normal cells least affected. Our previous study shows that combined PARP-1 inhibition with C ion reduces MMP-2,-9 synergistically in HeLa cells but detailed mechanism are not clear. To understand this mechanism and the rationale of using PARP-1 inhibitor with C ion radiotherapy for better outcome in controlling metastasis, we investigated metastatic potential in two non-small cell lung cancer (NSCLC) A549 and H1299 (p53-deficient) cells exposed with C ion in presence and absence of PARP-1 inhibition using siRNA or olaparib. We monitored cell proliferation, in-vitro cell migration, wound healing, expression and activity of MMP-2, - 9 in A549 and p53-deficient H1299 cell lines exposed with C ion with and without PARP-1 inhibitor olaparib/DPQ. Expression and phosphorylation of NF-kB, EGFR, Akt, p38, ERK was also observed in A549 and H1299 cells exposed with C ion with and without PARP-1 inhibition using siRNA or olaparib. We also checked expression of few marker genes involved in epithelial-mesenchymal transition (EMT) pathways like N-cadherin, vimentin, anillin, claudin-1, - 2 in both NSCLC. To determine the generalized effect of C ion and olaparib in inhibition of cell's metastatic potential, wound healing and activity of MMP-2, - 9 was also studied in HeLa and MCF7 cell lines after C ion exposure and in combination with PARP-1 inhibitor olaparib. Our experiments show that C ion and PARP-1 inhibition separately reduces cell proliferation, cell migration, wound healing, phosphorylation of EGFR, Akt, p38, ERK resulting inactivation of NF-kB. Combined treatment abolishes NF-kB expression and hence synergistically reduces MMP-2, - 9 expressions. Each single treatment reduces N-cadherin, vimentin, anillin but increases claudin-1, - 2 leading to suppression of EMT process. However, combined treatment synergistically alters these proteins to suppress EMT pathways significantly. The activation pathways of transcription of MMP-2,-9 via NF-kB and key marker proteins in EMT pathways are targeted by both C ion and olaparib/siRNA. Hence, C ion radiotherapy could potentially be combined with olaparib as chemotherapeutic agent for better control of cancer metastasis.