RESUMEN
Low-grade serous carcinoma represents a minority of serous carcinoma. Although they have better prognosis than high-grade serous carcinoma, they respond poorly to chemotherapy. Thus, it appears necessary to find other treatments such as targeted therapies. Since RAS or RAF mutations occur frequently in low-grade serous carcinoma and lead to constitutively activated MAPK cascade, MEK inhibition should be effective in the treatment of low-grade serous carcinoma. So, we wanted to evaluate the clinical benefit of MEK inhibitors in the management of advanced-stage low-grade serous carcinoma harboring KRAS or NRAS mutation. We report a case series of three women with advanced-stage low-grade serous carcinoma harboring RAS mutation who had stabilization of their disease during several months under targeted therapy combining anti-EGFR antibody and MEK inhibitor. We performed in vitro experiments, confirming the effectiveness of MEK inhibitor on the KRAS-mutated OVCAR-5 cell line, and the constitutively activation of MAPK cascade in RAS-mutated carcinoma. However, it seems that the anti-EGFR antibody does not provide any additional benefit. After whole exome analysis is carried out on the patient with the shortest response, we observed the appearance of RB1 loss-of-function mutation that could be a mechanism of resistance to MEK inhibitors in RAS- of RAF-mutated cancers. The MEK inhibitor is effective in the advanced stages of low-grade serous carcinoma harboring RAS mutation with acceptable tolerance. RB1 loss could be a mechanism of resistance to MEK inhibitors in RAS-mutated low-grade serous carcinoma.
Asunto(s)
Carcinoma , Cistadenocarcinoma Seroso , Neoplasias Ováricas , Carcinoma/tratamiento farmacológico , Cistadenocarcinoma Seroso/genética , Femenino , Humanos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Mutación , Neoplasias Ováricas/patología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismoRESUMEN
Chemotherapy with anti PD-1/PD-L1 antibodies has become the standard of care for patients with metastatic non-small cell lung cancer (mNSCLC). Using lung tumor models, where pemetrexed and cisplatin (PEM/CDDP) chemotherapy remains unable to synergize with immune checkpoint inhibitors (ICIs), we linked the failure of this treatment with its inability to induce CXCL10 expression and CD8+ T cell recruitment. Using drug screening, we showed that combining a MEK inhibitor (MEKi) with PEM/CDDP triggers CXCL10 secretion by cancer cells and CD8+ T cell recruitment, sensitizing it to ICIs. PEM/CDDP plus a MEKi promotes optineurin (OPTN)-dependent mitophagy, resulting in CXCL10 production in a mitochondrial DNA- and TLR9-dependent manner. TLR9 or autophagy/mitophagy inhibition abolishes the anti-tumor efficacy of PEM/CDDP plus MEKi/anti-PD-L1 therapy. In human NSCLCs, high OPTN, TLR9, and CXCL10 expression is associated with a better response to ICIs. Our results underline the role of TLR9- and OPTN-dependent mitophagy in enhancing chemoimmunotherapy efficacy.
Asunto(s)
Quimiocina CXCL10/genética , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Autofagia/efectos de los fármacos , Autofagia/genética , Antígeno B7-H1/antagonistas & inhibidores , Biomarcadores de Tumor , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Línea Celular Tumoral , Quimiocina CXCL10/metabolismo , Modelos Animales de Enfermedad , Resistencia a Antineoplásicos/efectos de los fármacos , Sinergismo Farmacológico , Humanos , Proteínas de Punto de Control Inmunitario/genética , Proteínas de Punto de Control Inmunitario/metabolismo , Ratones , Mitofagia/genética , Mitofagia/inmunología , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Unión Proteica , Inhibidores de Proteínas Quinasas/uso terapéutico , Transducción de Señal , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Trifluridine/tipiracil (FTD/TPI) is a new antimetabolite agent used to treat chemorefractory metastatic colorectal cancer. FTD/TPI induced immunogenic cell death (ICD) in vitro in the microsatellite-stable (MSS) CT26 mouse colon carcinoma cell line, as well as in various human MSS colorectal cancer cell lines (SW620, Caco-2, and Colo-320). The combination of FTD/TPI with oxaliplatin synergized to promote ICD. In vivo, the combination was able to induce ICD, but not the single agents, although all treatment groups showed T-cell dependency. In addition, FTD/TPI and oxaliplatin did not affect regulatory T cells or myeloid-derived suppressor cells but eliminated type-2 tumor-associated macrophages (TAM2), resulting in higher cytotoxic CD8+ T-cell infiltration and activation. This effect was concomitantly associated with PD-L1 expression on tumor cells and PD-1 induction on CD8+ T cells, leading to secondary T-cell exhaustion. Finally, although anti-PD-1 was unable to synergize with FTD/TPI or oxaliplatin monotherapy, concomitant administration of anti-PD-1 to FTD/TPI and oxaliplatin enhanced the antitumor efficacy of the double chemotherapy. Our study showed a novel immunomodulatory role of FTD/TPI and oxaliplatin in depleting TAM2. The combination of oxaliplatin and FTD/TPI induced ICD in vivo, providing a rationale for the use of these drugs to eliminate immunosuppressive cells and boost checkpoint efficacy in patients with metastatic colorectal cancer.