Withaferin A inhibits Epithelial to Mesenchymal Transition in Non-Small Cell Lung Cancer Cells

Abstract

Lung cancer is the leading cause of cancer-related deaths worldwide and in the United States. Despite recent advancements in treatment approaches, metastasis remains a major therapeutic challenge in lung cancer and explains the extremely poor prognosis. Epithelial to mesenchymal transition (EMT), a complex process of cellular reprogramming has become an attractive drug target because it plays a crucial role in the metastasis of non-small cell lung cancer (NSCLC). In the present study, we examined the effects of withaferin A (WFA), a plant-derived steroidal lactone on EMT in human NSCLC cell lines. First, we demonstrated that WFA displayed time- and concentration-dependent cytotoxicity on A549 and H1299 NSCLC cells. Then, cells were exposed to ≤ 0.5 µM WFA for ≤ 4 h to minimize cytotoxicity and determined its effects on EMT, cell adhesion, motility, migration, and invasion. EMT induction was performed by culturing cells in serum-free media containing TGFβ1 (5 ng/mL) and TNFα (25 ng/mL) for 48 h. We observed that pretreatment of cells with WFA inhibited cell adhesion, migration, and invasion of A549 and H1299 cells. Using western blot, immunofluorescence, and qRT-PCR analysis, we demonstrated that WFA suppressed TGFβ1 and TNFα-induced EMT in both cell lines. Mechanistically, WFA suppressed the phosphorylation and nuclear translocation of Smad2/3 and NF-κB in A549 and H1299 cells. Together, our study provides additional evidence demonstrating the inhibitory effects of WFA on EMT induction in NSCLC cells and further demonstrates the therapeutic potential of WFA against the metastasis in NSCLC.

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“…In addition, the TR-A549 cells displayed decreased E-cadherin expression, indicating an EMT phenotype which strongly suggests that EMT also plays a critical role in chemoresistance in NSCLC [43,52]. In a recent study [53], we have shown that WFA inhibits EMT in NSCLC cells, and we therefore strongly hypothesize that the use of PAC and WFA can prevent the emergence of drug resistance and metastasis in NSCLC. Together, these novel findings strongly support our rationale for combining PAC with WFA, and further suggest that this strategy has an additional benefit of the ability to prevent the emergence of drug resistance and metastasis in NSCLC.…”

Reversal of Epithelial–Mesenchymal Transition by Natural Anti-Inflammatory and Pro-Resolving Lipids

“…Withaferin A from the Solanaceae family attenuates bleomycin-induced scleroderma by targeting FoxO3a and NF-κB signaling [276]. Withaferin A (0.5 µM) can inhibit the EMT of NSCLC cells [277]. It (2 µM) can also inhibit the EMT of MCF10A cells and suppress vimentin expression in breast tumors [278].…”

Therapeutic potential of withaferin A against non-small cell lung cancer.

“…For example, studies [16,70,75] EMT phenotype in NSCLC. In a recent study [83], we have shown that WFA inhibits EMT in NSCLC cells, and we therefore strongly hypothesize that the use of PAC and WFA can prevent the emergence of drug resistance and metastasis in NSCLC. Together, these novel findings strongly support our rationale for combining PAC with WFA, and further suggest that this strategy has an additional benefit of the ability to prevent the emergence or target drug resistance and metastasis in NSCLC.…”

“…Chemically, WFA is a plant-derived steroidal-lactone that was first isolated from the alcoholic extracts of the Ayurvedic medicinal plant Withania somnifera [23,24,26]. In literature, there is a growing body of in vitro and in vivo preclinical data to demonstrable the efficacy of WFA against NSCLC [62,83], breast [31,35], cervical [66], prostate [39,94], pancreatic [67], renal [116], B-cell lymphoma [68] and ovarian cancers [43].…”

“…Mechanistically, it has been shown that WFA targets heat shock proteins [117], vimentin [31], NFkB [83], IKKβ-kinase [118], STAT3 [22], Blc2, cyclins, EGFR, and PAR-4 [30,94]. Together, these varied molecular targets allow WFA to disrupt multiple cellular processes such as proliferation, migration, invasion, and metastasis that are critical in the tumorigenesis of NSCLC cells [22].…”