Dr. Jekyll and Mr. Hyde: MAP17’s up-regulation, a crosspoint in cancer and inflammatory diseases

Inflammation is a common defensive response that is activated after different harmful stimuli. This chronic, or pathological, inflammation is also one of the causes of neoplastic transformation and cancer development. MAP17 is a small protein localized to membranes with a restricted pattern of expression in adult tissues. However, its expression is common in destabilized cells, as it is overexpressed both in inflammatory diseases and in cancer. MAP17 is overexpressed in most, if not all, carcinomas and in many tumors of mesenchymal origin, and correlates with higher grade and poorly differentiated tumors. This overexpression drives deep changes in cell homeostasis including increased oxidative stress, deregulation of signaling pathways and increased growth rates. Importantly, MAP17 is associated in tumors with inflammatory cells infiltration, not only in cancer but in various inflammatory diseases such as Barret’s esophagus, lupus, Crohn’s, psoriasis and COPD. Furthermore, MAP17 also modifies the expression of genes connected to inflammation, showing a clear induction of the inflammatory profile. Since MAP17 appears highly correlated with the infiltration of inflammatory cells in cancer, is MAP17 overexpression an important cellular event connecting tumorigenesis and inflammation?España Ministerio de Economía y Competitividad Fis: PI15/00045España Consejeria de Ciencia e Innovacion CTS-1848España Consejeria de Salud de la Junta de Andalucía PI-0096-201

NUMB and NUMBL differences in gene regulation

NUMB, and its close homologue NUMBL, behave as tumor suppressor genes by regulating the Notch pathway. The downregulation of these genes in tumors is common, allowing aberrant Notch pathway activation and tumor progression. However, some known differences between NUMB and NUMBL have raised unanswered questions regarding the redundancy and/or combined regulation of the Notch pathway by these genes during the tumorigenic process. We have found that NUMB and NUMBL exhibit mutual exclusivity in human tumors, suggesting that the associated tumor suppressor role is regulated by only one of the two proteins in a specific cell, avoiding duplicate signaling and simplifying the regulatory network. We have also found differences in gene expression due to NUMB or NUMBL downregulation. These differences in gene regulation extend to pathways, such as WNT or Hedgehog. In addition to these differences, the downregulation of either gene triggers a cancer stem cell-like related phenotype. These results show the importance of both genes as an intersection with different effects over cancer stem cell signaling pathways.España MINECO I+D+I 2013-2016ISCIII (Fis: PI15/00045)CIBER de Cáncer (CB16/12/00275

The cargo protein MAP17 (PDZK1IP1) regulates the immune microenvironment

Inflammation is a complex defensive response activated after various harmful stimuli allowing the clearance of damaged cells and initiating healing and regenerative processes. Chronic, or pathological, inflammation is also one of the causes of neoplastic transformation and cancer development. MAP17 is a cargo protein that transports membrane proteins from the endoplasmic reticulum. Therefore, its overexpression may be linked to an excess of membrane proteins that may be recognized as an unwanted signal, triggering local inflammation. Therefore, we analyzed whether its overexpression is related to an inflammatory phenotype. In this work, we found a correlation between MAP17 expression and inflammatory phenotype in tumors and in other inflammatory diseases such as Crohn's disease, Barrett's esophagus, COPD or psoriasis. MAP17 expression correlated also with the markers of inflammation HLAs, BBS10, HERC2, ADNP and PYCARD. Furthermore, we found that MAP17 expression directly regulates NFAT2 and IL-6 activation, inducing the differentiation of monocytes to dendritic cells and suggesting a causal role of MAP17 in inflammation. Immunohistochemistry confirms local inflammation, mainly CD45+ cells, at the site of expression of MAP17, at least in tumors, Crohn's and psoriasis. Therefore, our data indicates that the overexpression of the protein MAP17 plays important role in diseases involving chronic inflammation.España Ministerio de Economía y Competitividad FIS: PI15/00045Junta de Andalucía PI-0096-201

Role of Mitochondria in Cancer Stem Cell Resistance

Cancer stem cells (CSC) are associated with the mechanisms of chemoresistance to different cytotoxic drugs or radiotherapy, as well as with tumor relapse and a poor prognosis. Various studies have shown that mitochondria play a central role in these processes because of the ability of this organelle to modify cell metabolism, allowing survival and avoiding apoptosis clearance of cancer cells. Thus, the whole mitochondrial cycle, from its biogenesis to its death, either by mitophagy or by apoptosis, can be targeted by different drugs to reduce mitochondrial fitness, allowing for a restored or increased sensitivity to chemotherapeutic drugs. Once mitochondrial misbalance is induced by a specific drug in any of the processes of mitochondrial metabolism, two elements are commonly boosted: an increment in reactive nitrogen/oxygen species and, subsequently, activation of the intrinsic apoptotic pathway.Ministerio de Ciencia, Innovación y Universidades RTI2018-097455-B-I00, RED2018-102723-TJunta de Andalucía PI-0397-2017, P18-RT-250

Synthesis, reactivity studies, and cytotoxicity of two trans-Iodidoplatinum(II) complexes. Does photoactivation work?

trans-Platinum complexes have been the landmark in unconventional drugs prompting the development of innovative structures that might exhibit chemical and biological profiles different to cisplatin. Iodido complexes signaled a new turning point in the platinum drug design field when their cytotoxicity was reevaluated and reported. In this new study, we have synthesized and evaluated diodidoplatinum complexes trans-[PtI2(amine)(pyridine)] bearing aliphatic amines (isopropylamine and methylamine) and pyridines in trans configuration. X-ray diffraction data support the structural characterization. Their cytotoxicity has been evaluated in tumor cell lines such as SAOS-2, A375, T-47D, and HCT116. Moreover, we report their solution behavior and reactivity with biological models. Ultraviolet-a (UVA) irradiation induces an increase in their reactivity towards model nucleobase 5′-GMP in early stages, and promotes the release of the pyridine ligand (spectator ligand) at longer reaction times. Density Functional calculations have been performed and the results are compared with our previous studies with other iodido derivatives.MINECO CTQ-2015-68779

The cargo protein MAP17 (PDZK1IP1) regulates the cancer stem cell pool activating the Notch pathway by abducting NUMB

Purpose: Cancer stem cells (CSC) are self-renewing tumor cells, with the ability to generate diverse differentiated tumor cell subpopulations. They differ from normal stem cells in the deregulation of the mechanisms that normally control stem cell physiology. CSCs are the origin of metastasis and highly resistant to therapy. Therefore, the understanding of the CSC origin and deregulated pathways is important for tumor control. Experimental Design: We have included experiments in vitro, in cell lines and tumors of different origins. We have used patient-derived xenografts (PDX) and public transcriptomic databases of human tumors. Results: MAP17 (PDZKIP1), a small cargo protein overexpressed in tumors, interacts with NUMB through the PDZ-binding domain activating the Notch pathway, leading to an increase in stem cell factors and cancer-initiating–like cells. Identical behavior was mimicked by inhibiting NUMB. Conversely, MAP17 downregulation in a tumor cell line constitutively expressing this gene led to Notch pathway inactivation and a marked reduction of stemness. In PDX models, MAP17 levels directly correlated with tumorsphere formation capability. Finally, in human colon, breast, or lung there is a strong correlation of MAP17 expression with a signature of Notch and stem cell genes. Conclusions: MAP17 overexpression activates Notch pathway by sequestering NUMB. High levels of MAP17 correlated with tumorsphere formation and Notch and Stem gene transcription. Its direct modification causes direct alteration of tumorsphere number and Notch and Stem pathway transcription. This defines a new mechanism of Notch pathway activation and Stem cell pool increase that may be active in a large percentage of tumors.Ministerio de Economía y Competitividad PI15/00045, CTS-1848Junta de Andalucía PI-00-96-2014, PI-0306-201

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

Numb-like (NumbL) downregulation increases tumorigenicity, cancer stem cell-like properties and resistance to chemotherapy

NumbL, or Numb-like, is a close homologue of Numb, and is part of an evolutionary conserved protein family implicated in some important cellular processes. Numb is a protein involved in cell development, in cell adhesion and migration, in asymmetric cell division, and in targeting proteins for endocytosis and ubiquitination. NumbL exhibits some overlapping functions with Numb, but its role in tumorigenesis is not fully known. Here we showed that the downregulation of NumbL alone is sufficient to increase NICD nuclear translocation and induce Notch pathway activation. Furthermore, NumbL downregulation increases epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC)-related gene transcripts and CSC-like phenotypes, including an increase in the CSC-like pool. These data suggest that NumbL can act independently as a tumor suppressor gene. Furthermore, an absence of NumbL induces chemoresistance in tumor cells. An analysis of human tumors indicates that NumbL is downregulated in a variable percentage of human tumors, with lower levels of this gene correlated with worse prognosis in colon, breast and lung tumors. Therefore, NumbL can act as an independent tumor suppressor inhibiting the Notch pathway and regulating the cancer stem cell pool.España, Ministerio de Economía y Competitividad PI12/00137, PI15/00045España, Consejería de Ciencia e Innovación CTS-6844España, Consejería de Ciencia e Innovación CTS-1848España, Junta de Andalucía, Consejería de Salud PI-0306-2012España, Junta de Andalucía, Consejería 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

Dasatinib, a Src inhibitor, sensitizes liver metastatic colorectal carcinoma to oxaliplatin in tumors with high levels of phospho-Src.

Despite the development of new antineoplastic agents for the treatment of colorectal cancer (CRC), oxaliplatin and fluoropyrimidines remain the most commonly employed drugs for the treatment of both early and advanced disease. Intrinsic or acquired resistance is, however, an important limitation to pharmacological therapy, and the development of chemosensitization strategies constitute a major goal with important clinical implications. In the present work, we determined that high levels of activated Src kinase, measured as phospho-Src at the Tyr419 residue in CRC cell lines, can promote colorectal carcinoma cell resistance to oxaliplatin, but not to 5-fluorouracil (5FU), and that inhibition of this protein restores sensitivity to oxaliplatin. Similar results were observed with in vivo patient-derived xenograft (PDX) models that were orthotopically grown in murine livers. In PDX tumor lines derived from human CRC liver metastasis, dasatinib, a Src inhibitor, increases sensitivity to oxaliplatin only in tumors with high p-Src. However, dasatinib did not modify sensitivity to 5FU in any of the models. Our data suggest that chemoresistance induced by p-Src is specific to oxaliplatin, and that p-Src levels can be used to identify patients who may benefit from this combination therapy. These results are relevant for clinicians as they identify a novel biomarker of drug resistance that is suitable to pharmacological manipulation.HUVR-IBiS Biobanco del Sistema Sanitario Público de Andalucía y ISCIII-Red de Biobancos [PT13/0010/0056].FEDER from Regional Development European Funds (European Union), Ministerio de Economía y Competitividad, Plan Nacional de I+D+I 2008-2011, Plan Estatal de I+D+i 2013-2016, ISCIII [Fis: PI12/00137, PI13/02295, PI15/00045, RTICC: RD12/0036/0028].Consejería de Ciencia e Innovación [CTS-1848] y Consejería de Salud de la Junta de Andalucía [PI-0306-2012, PI-0096-2014]