La hipoxia induce la activación de los macrófagos potenciando la fagocitosis y la presentación antigénica, a través de la producción de IFN- gamma, mediada por el factor de transcripción HIF-1 alfa

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 29-06-0

CD13 as a new tumor target for antibody-drug conjugates: validation with the conjugate MI130110

BACKGROUND: In the search for novel antibody-drug conjugates (ADCs) with therapeutic potential, it is imperative to identify novel targets to direct the antibody moiety. CD13 seems an attractive ADC target as it shows a differential pattern of expression in a variety of tumors and cell lines and it is internalized upon engagement with a suitable monoclonal antibody. PM050489 is a marine cytotoxic compound tightly binding tubulin and impairing microtubule dynamics which is currently undergoing clinical trials for solid tumors. METHODS: Anti-CD13 monoclonal antibody (mAb) TEA1/8 has been used to prepare a novel ADC, MI130110, by conjugation to the marine compound PM050489. In vitro and in vivo experiments have been carried out to demonstrate the activity and specificity of MI130110. RESULTS: CD13 is readily internalized upon TEA1/8 mAb binding, and the conjugation with PM050489 did not have any effect on the binding or the internalization of the antibody. MI130110 showed remarkable activity and selectivity in vitro on CD13-expressing tumor cells causing the same effects than those described for PM050489, including cell cycle arrest at G2, mitosis with disarrayed and often multipolar spindles consistent with an arrest at metaphase, and induction of cell death. In contrast, none of these toxic effects were observed in CD13-null cell lines incubated with MI130110. Furthermore, in vivo studies showed that MI130110 exhibited excellent antitumor activity in a CD13-positive fibrosarcoma xenograft murine model, with total remissions in a significant number of the treated animals. Mitotic catastrophes, typical of the payload mechanism of action, were also observed in the tumor cells isolated from mice treated with MI130110. In contrast, MI130110 failed to show any activity in a xenograft mouse model of myeloma cells not expressing CD13, thereby corroborating the selectivity of the ADC to its target and its stability in circulation. CONCLUSION: Our results show that MI130110 ADC combines the antitumor potential of the PM050489 payload with the selectivity of the TEA1/8 monoclonal anti-CD13 antibody and confirm the correct intracellular processing of the ADC. These results demonstrate the suitability of CD13 as a novel ADC target and the effectiveness of MI130110 as a promising antitumor therapeutic agent.This work was partially supported by grant IPT-2012-0198-090000 (“MARINMAB” project) from Ministerio de Economía y Competitividad (MINECO) and European Regional Development’s funds (ERDF) and by CSIC grant 2019AEP146.S

Induction of the mitochondrial NDUFA4L2 protein by HIF-1α decreases oxygen consumption by inhibiting complex i activity

The fine regulation of mitochondrial function has proved to be an essential metabolic adaptation to fluctuations in oxygen availability. During hypoxia, cells activate an anaerobic switch that favors glycolysis and attenuates the mitochondrial activity. This switch involves the hypoxia-inducible transcription factor-1 (HIF-1). We have identified a HIF-1 target gene, the mitochondrial NDUFA4L2 (NADH dehydrogenase [ubiquinone] 1 alpha subcomplex, 4-like 2). Our results, obtained employing NDUFA4L2-silenced cells and NDUFA4L2 knockout murine embryonic fibroblasts, indicate that hypoxia-induced NDUFA4L2 attenuates mitochondrial oxygen consumption involving inhibition of Complex I activity, which limits the intracellular ROS production under low-oxygen conditions. Thus, reducing mitochondrial Complex I activity via NDUFA4L2 appears to be an essential element in the mitochondrial reprogramming induced by HIF-1This work was supported by Ministerio de Ciencia e Innovación (SAF 2007-06592, SAF2010-14851), Comunidad Autónoma de Madrid (SAL 2006/ 0311), Metoxia Project-Health (F2 2009-222741), and Recava Network (RD 06/0014/0031) to M.O.L.; PS09/00101 and CP07/00143 to A.M.-R.; PI060701, PS09/00116, and CP08/00204 to S.C.; BFU2008-03407/BMC to J.A.; SAF2009-08007 to J.A.E.; and CSD2007-00020 to A.M.-R. and J.A.E. The CNIC is supported by the Instituto de Salud Carlos III-MICINN and the Pro-CNIC Foundation. We are grateful to Mike Murphy (Mitochondrial Biology Unit, MRC, Cambridge, UK) for the gift of MitoQ. We also thank Stephen Y. Chan and Joseph Loscalzo (Harvard Medical School, Boston, MA) for providing us ISCU expression vector

The mitotic cancer target PLK1 modulates mouse endothelial homeostasis and in vitro angiogenesis

Trabajo presentado en la 18th Aseica International Conference, celebrada en Santiago de Compostela (España) del 16 al 18 de noviembre de 2022

The mitotic cancer target plk1 modulates mouse endothelial homeostasis and in vitro angiogenesis

Trabajo presentado en el II Congreso Anual de la Red Conexión Cáncer, celebrado en Benidorm (España) del 23 al 25 de enero de 2023

Induction of the Mitochondrial NDUFA4L2 Protein by HIF-1α Decreases Oxygen Consumption by Inhibiting Complex I Activity

The fine regulation of mitochondrial function has proved to be an essential metabolic adaptation to fluctuations in oxygen availability. During hypoxia, cells activate an anaerobic switch that favors glycolysis and attenuates the mitochondrial activity. This switch involves the hypoxia-inducible transcription factor-1 (HIF-1). We have identified a HIF-1 target gene, the mitochondrial NDUFA4L2 (NADH dehydrogenase [ubiquinone] 1 alpha subcomplex, 4-like 2). Our results, obtained employing NDUFA4L2-silenced cells and NDUFA4L2 knockout murine embryonic fibroblasts, indicate that hypoxiainduced NDUFA4L2 attenuates mitochondrial oxygen consumption involving inhibition of Complex I activity, which limits the intracellular ROS production under low-oxygen conditions. Thus, reducing mitochondrial Complex I activity via NDUFA4L2 appears to be an essential element in the mitochondrial reprogramming induced by HIF-1.Ministerio de Ciencia e InnovaciónComunidad Auto´ noma de Madrid (SAL 2006/ 0311), Metoxia Project-Health (F2 2009-222741), and Recava Network (RD 06/0014/0031) to M.O.L.; PS09/00101 and CP07/00143 to A.M.-R.; PI060701, PS09/00116, and CP08/00204 to S.C.; BFU2008-03407/BMC to J.A.; SAF2009-08007 to J.A.E.; and CSD2007-00020Depto. de Bioquímica y Biología MolecularTRUEpu