ABSTRACT
Background: The development of molecular targeted therapies, such as EGFR-TKIs, has positively impacted the management of EGFR mutated NSCLC. However, patients with innate and acquired resistance to EGFR-TKIs still face limited effective therapeutic options. Statins are the most frequently prescribed anti-cholesterol agents and have been reported to inhibit the progression of various malignancies, including in lung. However, the mechanism by which statin exerts its anti-cancer effects is unclear. This study is designed to investigate the anti-proliferative effects and identify the mechanism-of-action of statins in NSCLC. Methods: In this study, the anti-tumoral properties of Atorvastatin were investigated in NSCLC utilizing cell culture system and in vivo models. Results: We demonstrate a link between elevated cellular cholesterol and TKI-resistance in NSCLC, which is independent of EGFR mutation status. Atorvastatin suppresses growth by inhibiting Cav1 expression in tumors in cell culture system and in in vivo models. Subsequent interrogations demonstrate an oncogenic physical interaction between Cav1 and GLUT3, and glucose uptake found distinctly in TKI-resistant NSCLC and this may be due to changes in the physical properties of Cav1 favoring GLUT3 binding in which significantly stronger Cav1 and GLUT3 physical interactions were observed in TKI-resistant than in TKI-sensitive NSCLC cells. Further, the differential effects of atorvastatin observed between EGFR-TKI resistant and sensitive cells suggest that EGFR mutation status may influence its actions. Conclusions: This study reveals the inhibition of oncogenic role of Cav1 in GLUT3-mediated glucose uptake by statins and highlights its potential impact to overcome NSCLC with EGFR-TKI resistance.
Subject(s)
Antineoplastic Agents/pharmacology , Atorvastatin/pharmacology , Carcinoma, Non-Small-Cell Lung/drug therapy , Caveolin 1/metabolism , Glucose Transporter Type 3/metabolism , Lung Neoplasms/drug therapy , Signal Transduction/drug effects , Animals , Caveolin 1/genetics , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Energy Metabolism/drug effects , ErbB Receptors/genetics , Female , Glucose/metabolism , Glucose Transporter Type 3/genetics , Humans , Lung/drug effects , Male , Mice , Molecular Targeted Therapy , MutationABSTRACT
Fatty acid synthase (FASN) is a lipogenic enzyme that is selectively upregulated in malignant cells. There is growing consensus on the oncogenicity of FASN-driven lipogenesis and the potential of FASN as a druggable target in cancer. Here, we report the synthesis and FASN inhibitory activities of two novel galloyl esters of trans-stilbene EC1 and EC5. Inhibition of FASN was accompanied by a loss in AKT activation and profound apoptosis in several non-small cell lung cancer (NSCLC) cells at the growth inhibitory concentrations of EC1 and EC5. Both FASN and phospho-AKT levels were concurrently downregulated. However, addition of a lipid concentrate to the treated cells reinstated cell viability and reversed the loss of FASN and AKT protein levels, thus recapitulating the causal relationship between FASN inhibition and the loss in cell viability.
Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Non-Small-Cell Lung/drug therapy , Esters/pharmacology , Fatty Acid Synthase, Type I/antagonists & inhibitors , Gallic Acid/pharmacology , Lung Neoplasms/drug therapy , Stilbenes/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Esters/chemical synthesis , Esters/chemistry , Fatty Acid Synthase, Type I/metabolism , Gallic Acid/analogs & derivatives , Gallic Acid/chemistry , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Molecular Structure , Stilbenes/chemical synthesis , Stilbenes/chemistry , Structure-Activity RelationshipABSTRACT
Metabolic reprogramming is widely known as a hallmark of cancer cells to allow adaptation of cells to sustain survival signals. In this report, we describe a novel oncogenic signaling pathway exclusively acting in mutated epidermal growth factor receptor (EGFR) non-small cell lung cancer (NSCLC) with acquired tyrosine kinase inhibitor (TKI) resistance. Mutated EGFR mediates TKI resistance through regulation of the fatty acid synthase (FASN), which produces 16-C saturated fatty acid palmitate. Our work shows that the persistent signaling by mutated EGFR in TKI-resistant tumor cells relies on EGFR palmitoylation and can be targeted by Orlistat, an FDA-approved anti-obesity drug. Inhibition of FASN with Orlistat induces EGFR ubiquitination and abrogates EGFR mutant signaling, and reduces tumor growths both in culture systems and in vivo Together, our data provide compelling evidence on the functional interrelationship between mutated EGFR and FASN and that the fatty acid metabolism pathway is a candidate target for acquired TKI-resistant EGFR mutant NSCLC patients.
