Osimertinib-resistant NSCLC cells activate ERBB2 and YAP/TAZ and are killed by neratinib.
We performed additional mechanistic analyses to redefine neratinib biology and determined the mechanisms by which the multi-kinase inhibitor neratinib interacted with the thymidylate synthase inhibitor pemetrexed to kill NSCLC cells expressing either mutant KRAS (G12S; Q61H; G12A; G12C) or mutant NRAS (Q61K) or mutant ERBB1 (L858R; L858R T790M; exon 19 deletion). Neratinib rapidly reduced KRASG12V and RAC1G12V nanoclustering which was followed by KRASG12V, but not RAC1G12V, being extensively mislocalized away from the plasma membrane. This correlated with reduced levels of, and reorganized membrane localization of phosphatidylserine and cholesterol. Reduced nanoclustering was not associated with inactivation of ERBB1, Merlin or Ezrin. The drug combination killed cells expressing mutant KRAS, NRAS or mutant ERBB1 proteins. Afatinib or osimertinib resistant cells were killed with a similar efficacy to non-resistant cells. Compared to osimertinib-resistant cells, sensitive cells had less ERBB2 Y1248 phosphorylation. In osimertinib resistant H1975 cells, the drug combination was less capable of inactivating AKT, mTOR, STAT3, STAT5, ERK1/2 whereas it gained the ability to inactivate ERBB3. In resistant H1650 cells, the drug combination was less capable of inactivating JAK2 and STAT5. Sensitive cells exhibited elevated basal phosphorylation of YAP and TAZ. In resistant cells, portions of YAP and TAZ were localized in the nucleus. [Neratinib + pemetrexed] increased phosphorylation of YAP and TAZ, caused their nuclear exit, and enhanced ERBB2 degradation. Thus, neratinib targets an unidentified protein whose functional inhibition directly results in RAS inactivation and tumor cell killing. Our data prove that, albeit indirectly, oncogenic RAS proteins are druggable by neratinib.
['Dent|Paul|P|', 'Booth|Laurence|L|', 'Poklepovic|Andrew|A|', 'Von Hoff|Daniel|D|', 'Martinez|Jennifer|J|', 'Zhou|Yong|Y|', 'Hancock|John F|JF|']
D000178:Acrylamides D048868:Adaptor Proteins, Signal Transducing D000230:Adenocarcinoma D000814:Aniline Compounds D000970:Antineoplastic Agents D002289:Carcinoma, Non-Small-Cell Lung D045744:Cell Line, Tumor D002470:Cell Survival D015972:Gene Expression Regulation, Neoplastic D006801:Humans D047908:Intracellular Signaling Peptides and Proteins D008175:Lung Neoplasms D000068437:Pemetrexed D011804:Quinolines D018719:Receptor, ErbB-2 D014157:Transcription Factors D000091364:Transcriptional Coactivator with PDZ-Binding Motif Proteins D000091102:YAP-Signaling Proteins
ERBB2 Neratinib Autophagy, ER stress Hippo, YAP, TAZ, pemetrexed eIF2α