Combination treatment of Src inhibitor Saracatinib with GMI, a Ganoderma microsporum immunomodulatory protein, induce synthetic lethality via autophagy and apoptosis in lung cancer cells

Abstract

Saracatinib is an oral Src-kinase inhibitor and has been studied in preclinical models and clinical trials of cancer therapy. GMI, a fungal immunomodulatory protein from Ganoderma microsporum, possesses antitumor capacity. The aim of this study is to evaluate the cytotoxic effect of combination treatment with saracatinib and GMI on parental and pemetrexed-resistant lung cancer cells. Cotreatment with saracatinib and GMI induced synergistic and additive cytotoxic effect in A549 and A400 cells by annexin V/propidium iodide assay and combination index. Using western blot assay, saracatinib, and GMI combined treatment synergistically induced caspase-7 activation in A549 cells. Different from A549 cells, saracatinib and GMI cotreatment markedly increased LC3B-II in A400 cells. ATG5 silencing abolished the caspase-7 activation and reduced cell death in A549 cells after cotreatment. This is the first study to provide a novel strategy of treating lung cancer with or without drug resistance via combination treatment with GMI and saracatinib.

Suppression of PI3K/Akt/mTOR/c-Myc/mtp53 Positive Feedback Loop Induces Cell Cycle Arrest by Dual PI3K/mTOR Inhibitor PQR309 in Endometrial Cancer Cell Lines

“…Anti-phospho-Akt Ser473 (#9271, Cell Signaling, Danvers, MA, USA), anti-Akt (#9272, Cell Signaling, Danvers, MA, USA), anti-LC3B (#3868, Cell Signaling, Danvers, MA, USA), anti-CDK6 (#13331, Cell Signaling, Danvers, MA, USA), anti-p27 (#sc1641, Santa Cruz Biotechnology, Dallas , TX, USA), anti-endoglin (AF1097, R&D, Minneapolis, MN, USA), anti-kallikrein 6 (KLK6; AF2008, R&D, Minneapolis, MN, USA), anti-p53 (M 7001, DakoCytomation, Glostrup, Denmark), anti-survivin (#2808, Cell Signaling, Danvers, MA, USA), anti-hTERT (#ab32020, abcam, Cambridge, UK), anti-c-Myc (MAB3696, R&D, Minneapolis, MN, USA), Anti-phospho-p70S6K Thr389 (#9234, Cell Signaling, Danvers, MA, USA), anti- p70S6K (#9202, Cell Signaling, Danvers, MA, USA), and anti-β-actin (AC-40, Sigma, St. Louis, MO, USA) were used to detect the expressions of indicated protein. The complete protocol for Western blot assay has been described in a previous publication [ 12 ].…”

Safety assessment of the fungal immunomodulatory protein from Ganoderma microsporum (GMI) derived from engineered Pichia pastoris: Genetic toxicology, a 13-week oral gavage toxicity study, and an embryo-fetal developmental toxicity study in Sprague-Dawley rats

“…A 2.0 Å structure of GMI was solved and GMI showed a dimer:dimer quaternary structure with non-covalent interactions through the N-terminal helices (PDB ID 3KCW, [16] ). Furthermore, GMI with the same quality were evaluated in the platform for the anti-tumor activity and immunomodulation under immune disorder/disease model, and GMI showed a variety of bioactivities in the application for oncology [45] , [46] , [47] , [48] , [49] , [50] , [51] , [52] , [44] , [43] , immuno-oncology [53] , [54] , [55] , [56] , [57] , and immunology [59] , [60] , [62] , [63] , [64] , [61] , [58] , [65] . Although these promising findings are attractive for the further clinical application, the quality and the safety are always the major concerns.…”

LncTx: A network-based method to repurpose drugs acting on the survival-related lncRNAs in lung cancer

“…Hence, according to Vennepureddy et al [74] , topotecan in combination with other agents was recommended as the first-line advanced NSCLC therapy if the patient cannot tolerate the standard platinum-based therapy. Saracatinib is a Src-kinase inhibitor used to treat NSCLC in vivo [83] . Saracatinib seemed to be able to restore the epithelial-mesenchymal transition and disrupt spheroidogenesis in ovarian cancer cell lines and the subcutaneous xenograft model [84] .…”