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Kinase inhibitors are widely used to treat cancer, however patients frequently develop resistance. Here, the authors investigate adaption mechanisms during drug persistence and show that stimulation of the innate immunity sensor RIG-I enhances cancer cell death when combined with kinase inhibition. Kinase inhibitors suppress the growth of oncogene driven cancer but also enforce the selection of treatment resistant cells that are thought to promote tumor relapse in patients. Here, we report transcriptomic and functional genomics analyses of cells and tumors within their microenvironment across different genotypes that persist during kinase inhibitor treatment. We uncover a conserved, MAPK/IRF1-mediated inflammatory response in tumors that undergo stemness- and senescence-associated reprogramming. In these tumor cells, activation of the innate immunity sensor RIG-I via its agonist IVT4, triggers an interferon and a pro-apoptotic response that synergize with concomitant kinase inhibition. In humanized lung cancer xenografts and a syngeneic Egfr-driven lung cancer model these effects translate into reduction of exhausted CD8(+) T cells and robust tumor shrinkage. Overall, the mechanistic understanding of MAPK/IRF1-mediated intratumoral reprogramming may ultimately prolong the efficacy of targeted drugs in genetically defined cancer patients.

Molecular agents targeting the epidermal growth factor receptor (EGFR)-, anaplastic lymphoma kinase (ALK)- or c-ros oncogene 1 (ROS1) alterations have revolutionized the treatment of oncogene-driven non-small-cell lung cancer (NSCLC). However, the emergence of acquired resistance remains a significant challenge, limiting the wider clinical success of these molecular targeted therapies. In this study, we investigated the efficacy of various molecular targeted agents, including erlotinib, alectinib, and crizotinib, combined with anti-vascular endothelial growth factor receptor (VEGFR) 2 therapy. The combination of VEGFR2 blockade with molecular targeted agents enhanced the anti-tumor effects of these agents in xenograft mouse models of EGFR-, ALK-, or ROS1-altered NSCLC. The numbers of CD31-positive blood vessels were significantly lower in the tumors of mice treated with an anti-VEGFR2 antibody combined with molecular targeted agents compared with in those of mice treated with molecular targeted agents alone, implying the antiangiogenic effects of VEGFR2 blockade. Additionally, the combination therapies exerted more potent antiproliferative effects in vitro in EGFR-, ALK-, or ROS1-altered NSCLC cells, implying that VEGFR2 inhibition also has direct anti-tumor effects on cancer cells. Furthermore, VEGFR2 expression was induced following exposure to molecular targeted agents, implying the importance of VEGFR2 signaling in NSCLC patients undergoing molecular targeted therapy. In conclusion, VEGFR2 inhibition enhanced the anti-tumor effects of molecular targeted agents in various oncogene-driven NSCLC models, not only by inhibiting tumor angiogenesis but also by exerting direct antiproliferative effects on cancer cells. Hence, combination therapy with anti-VEGFR2 antibodies and molecular targeted agents could serve as a promising treatment strategy for oncogene-driven NSCLC.

A 68-year-old man presented with a solid mass at the left renal pelvis and ureter with multiple systemic lymphadenopathies and a mass with a cavity in the right lower lobe of the lung. While a transbronchial lung biopsy revealed no malignancy, a biopsy of the renal pelvis showed marginal zone lymphoma with polyclonal IgG4-positive cells. The serum IgG4 level and presence of a bilateral orbital mass suggested Mikulicz disease. The lesions shrank following the administration of steroids. A rebiopsy confirmed lung adenocarcinoma, and its background showed IgG4-positive cells a year later. IgG4-related diseases require careful follow-up because they can be complicated by malignancy.

A 66-year-old man was transferred to our hospital for pneumonia that was resistant to sulbactam/ampicillin and levofloxacin therapy. Chest computed tomography showed the rapidly progressive formation of multiple cavities. Methicillin-resistant Staphylococcus aureus (MRSA) was isolated, and the patient was diagnosed with necrotizing pneumonia caused by community-acquired MRSA (CA-MRSA). The MRSA strain had type IV staphylococcus cassette chromosome mec and genes encoding Panton-Valentine leucocidin (PVL). CA-MRSA necrotizing pneumonia with the PVL gene is rare; only three cases have been previously reported in Japan. We administered anti-MRSA antibiotics and the patient achieved complete clinical and radiological improvement.