Determinación del papel de FGFR1 y FGFR4 en cáncer de pulmón.

El cáncer de pulmón representa uno de los tipos de cáncer con mayor incidencia y mortalidad. Su caracterización molecular ha permitido identificar alteraciones moleculares conductoras de esta patología, algunas de las cuales son abordables terapéuticamente. Éste es el caso de FGFR1 y FGFR4, cuya amplificación o sobreexpresión ha demostrado estar asociada a este tipo de tumores y correlacionada con un peor pronóstico de los pacientes afectos. Se han desarrollado diferentes inhibidores dirigidos frente a los FGFRs, actualmente en ensayos clínicos en diferentes tipos tumorales, incluido el de pulmón. Sin embargo, a pesar de los prometedores resultados obtenidos con estos inhibidores en estudios preclínicos, su eficacia a nivel clínico ha sido más que modesta. La causa de esto se ha atribuido a la ausencia de criterios de selección de pacientes apropiados para recibir este tipo de terapia. Por todo esto, el objetivo de este trabajo de tesis es la elucidación del papel de ambos FGFRs en la tumorogénesis pulmonar y de sus implicaciones clínicas, así como la determinación de factores predictivos de respuesta a sus inhibidores. A lo largo del presente trabajo, mediante la realización de técnicas experimentales in vitro, in vivo y de análisis de muestras tumorales de cohortes de pacientes con cáncer de pulmón, describiremos el papel de FGFR1 y FGFR4 en la biología del cáncer de pulmón dependiente del contexto molecular. La expresión de cualquiera de estos receptores provoca efectos pro-tumorogénicos en dos contextos diferentes. Por un lado, en modelos con sobreactivación de EGFR, ambos FGFRs interaccionan físicamente con EGFR, produciéndose una activación recíproca de ambos tipos de receptores y de las rutas de señalización oncogénicas canónicas de éstos. En línea con estos resultados, los tratamientos combinados con inhibidores de EGFR y FGFR presentan gran eficacia en modelos de xenoinjertos de tumores derivados de pacientes con alta expresión de FGFR1 y/o FGFR4 y activación de EGFR. Además, el análisis de una cohorte de pacientes tratados con inhibidores de EGFR en monoterapia señala que los pacientes con tumores con alta expresión de FGFR1 y/o FGFR4 presentan peor respuesta al tratamiento. Por otro lado, en modelos con sobreexpresión de N-cadherina, esta molécula de adhesión interacciona con ambos receptores provocando su activación y la de su señalización oncogénica. De acuerdo a esto, el tratamiento con inhibidores de FGFR es efectivo solo en los modelos de tumores derivados de pacientes con alta expresión de FGFR1 y/o FGFR4, y de N-cadherina. Además, el análisis de varias cohortes independientes de pacientes indica que la N-cadherina tiene un papel pronóstico en los pacientes afectos de tumores pulmonares con alta expresión de FGFR1 y/o FGFR4, correlacionando con supervivencias más acortadas. Sin embargo, en ausencia de activación de EGFR y de expresión de N-cadherina, ambos FGFRs ejercen un efecto supresor tumoral mediante una disminución de la señalización oncogénica asociada a estos receptores. En vista a los resultados obtenidos en este trabajo de tesis doctoral, se propone que la determinación de la expresión de FGFR1 y FGFR4 no es suficiente para determinar la efectividad de los inhibidores de FGFR. La determinación complementaria de la activación de EGFR y de la expresión de N-cadherina podría ser clave para la selección de la terapia a aplicar a cada paciente.Premio Extraordinario de Doctorado U

MAP17 predicts sensitivity to platinum-based therapy, EGFR inhibitors and the proteasome inhibitor bortezomib in lung adenocarcinoma

Background The high incidence and mortality of lung tumours is a major health problem. Therefore, the identification both of biomarkers predicting efficacy for therapies in use and of novel efficacious therapeutic agents is crucial to increase patient survival. MAP17 (PDZK1IP1) is a small membrane-bound protein whose upregulation is reported as a common feature in tumours from diverse histological origins. Furthermore, MAP17 is correlated with tumour progression. Go to: Methods We assessed the expression of MAP17 in preclinical models, including cell lines and patient-derived xenografts (PDXs), assessing its correlation with sensitivity to different standard-of-care drugs in lung adenocarcinoma, as well as novel drugs. At the clinical level, we subsequently correlated MAP17 expression in human tumours with patient response to these therapies. Go to: Results We show that MAP17 expression is induced during lung tumourigenesis, particularly in lung adenocarcinomas, and provide in vitro and in vivo evidence that MAP17 levels predict sensitivity to therapies currently under clinical use in adenocarcinoma tumours, including cisplatin, carboplatin and EGFR inhibitors. In addition, we show that MAP17 expression predicts proteasome inhibitor efficacy in this context and that bortezomib, an FDA-approved drug, may be a novel therapeutic approach for MAP17-overexpressing lung adenocarcinomas. Go to: Conclusions Our results indicate a potential prognostic role for MAP17 in lung tumours, with particular relevance in lung adenocarcinomas, and highlight the predictive pot0065ntial of this membrane-associated protein for platinum-based therapy and EGFR inhibitor efficacy. Furthermore, we propose bortezomib treatment as a novel and efficacious therapy for lung adenocarcinomas exhibiting high MAP17 expression

Coordinated downregulation of Spinophilin and the catalytic subunits of PP1, PPP1CA/B/C, contributes to a worse prognosis in lung cancer

The scaffold protein Spinophilin (Spinophilin, PPP1R9B) is one of the regulatory subunits of phosphatase-1 (PP1), directing it to distinct subcellular locations and targets. The loss of Spinophilin reduces PP1 targeting to pRb, thereby maintaining higher levels of phosphorylated pRb. Spinophilin is absent or reduced in approximately 40% of human lung tumors, correlating with the malignant grade. However, little is known about the relevance of the coordinated activity or presence of Spinophilin and its reported catalytic partners in the prognosis of lung cancer. In the present work, we show that the downregulation of Spinophilin, either by protein or mRNA, is related to a worse prognosis in lung tumors. This effect is more relevant in squamous cell carcinoma, SCC, than in adenocarcinoma. Downregulation of Spinophilin is related to a decrease in the levels of its partners PPP1CA/B/C, the catalytic subunits of PP1. A decrease in these subunits is also related to prognosis in SCC and, in combination with a decrease in Spinophilin, are markers of a poor prognosis in these tumors. The analysis of the genes that correlate to Spinophilin in lung tumors showed clear enrichment in ATP biosynthesis and protein degradation GO pathways. The analysis of the response to several common and pathway-related drugs indicates a direct correlation between the Spinophilin/PPP1Cs ratio and the response to oxaliplatin and bortezomib. This finding indicates that this ratio may be a good predictive biomarker for the activity of the drugs in these tumors with a poor prognosis.España, Mineco Plan Estatal de I+D+I 2013-2016España, ISCIII Fis: PI15/00045CIBER de Cáncer CB16/12/00275, CB16/12/00443, CB16/12/00442España, Junta de Andalucía, Consejeria de Ciencia e Innovacion CTS-1848España, Junta de Andalucía, Consejeria de Salud PI-0096-201

FGFR1 Cooperates with EGFR in Lung Cancer Oncogenesis, and Their Combined Inhibition Shows Improved Efficacy

Introduction: There is substantial evidence for the onco- genic effects of fi broblast growth factor receptor 1 (FGFR1) in many types of cancer, including lung cancer, but the role of this receptor has not been addressed speci fi cally in lung adenocarcinoma. Methods: We performed FGFR1 and EGFR overexpression and co-overexpression assays in adenocarcinoma and in inmortalized lung cell lines, and we also carried out surrogateandinteractionassays.Weperformedmono- therapy and combination EGFR /FGFR inhibitor sensitivity assays in vitro and in vivo in cell line – and patient- derived xenografts. We determined FGFR1 mRNA expression in a cohort of patients with anti – EGFR ther- apy – treated adenocarcinoma. Results: We have reported a cooperative interaction between FGFR1 and EGFR in this context, resulting in increased EGFR activation and oncogenic signaling. We have provided in vitro and in vivo evidence indicating that FGFR1 expression in- creases tumorigenicity in cells with high EGFR activation in EGFR-mutated and EGFR wild-type models. At the clinical level, we have shown that high FGFR1 expression levels pre- dict higher resistance to erlotinib or ge fi tinib in a cohort of patients with tyrosine kinase inhibitor – treated EGFR-mutated and EGFR wild-type lung adenocarcinoma. Dual EGFR and FGFR inhibition in FGFR1-over expressing, EGFR-activated models shows synergistic effects on tumor growth in vitro and in cell line – and patient-derived xenografts, suggesting that patients with tumors bearing these characteristics may bene fi t from combined EGFR/FGFR inhibition. Conclusion: These results support the extended the use of EGFR inhibitors beyond monotherapy in the EGFR-mutated adenocarcinoma setting in combination with FGFR in- hibitors for selected patients with increased FGFR1 over- expression and EGFR activation.ISCIII PI14/01964 PIE15/00076 PI17/00778 DTS17/00089 PI15/00045 PI17/00033 PI16/01311 FI12/00429CIBERONC CD16/12/00442FEDER CD16/12/00442 PI16/01311Spanish Ministry of Economy and Competitiveness PI15/00045Ministry of Health and Social Welfare of Junta de Andalucía PI-0046-2012 C-0040-2016Ministry of Equality, Health and Social Policies of the Junta de Andalucía PI- 0029-2013Comunidad de Madrid B2017/BMD3884Ministry of Education, Culture and Sports FPU13/0259