New indolesulfonamide derivatives targeting the colchicine site of tubulin: synthesis, anti-tumour activity, structure–activity relationships, and molecular modelling

Searching for improved indolesulfonamides with higher polarities, 45 new analogues with modifications on the sulfonamide nitrogen, the methoxyaniline, and/or the indole 3-position were synthesised. They show submicromolar to nanomolar antiproliferative IC50 values against four human tumour cell lines and they are not P-glycoprotein substrates as their potencies against HeLa cells did not improve upon cotreatment with multidrug resistance (MDR) inhibitors. The compounds inhibit tubulin polymerisation in vitro and in cells, thus causing a mitotic arrest followed by apoptosis as shown by cell cycle distribution studies. Molecular modelling studies indicate binding at the colchicine site. Methylated sulfonamides were more potent than those with large and polar substitutions. Amide, formyl, or nitrile groups at the indole 3-position provided drug-like properties for reduced toxicity, with Polar Surface Areas (PSA) above a desirable 75 Å2. Nitriles 15 and 16 are potent polar analogues and represent an interesting class of new antimitotics.This work was financially supported by the Consejería de Educación de la Junta de Castilla y León [SA262P18 and SA116P20], co-funded by the EU’s European Regional Development Fund-FEDER, and the Spanish Ministry of Science, Innovation, and Universities [RTI2018-099474-B-I00]

Methoxy and bromo scans on N-(5-methoxyphenyl) methoxybenzenesulphonamides reveal potent cytotoxic compounds, especially against the human breast adenocarcinoma MCF7 cell line

Thirty seven N-(5-methoxyphenyl)-4-methoxybenzenesulphonamide with methoxy or/and bromo substitutions (series 1-4) and with different substituents on the sulphonamide nitrogen have been synthesised. 21 showed sub-micromolar cytotoxicity against HeLa and HT-29 human tumour cell lines, and were particularly effective against MCF7. The most potent series has 2,5-dimethoxyanilines, especially the 4-brominated compounds 23–25. The active compounds inhibit microtubular protein polymerisation at micromolar concentrations, thus pointing at tubulin as the target. Co-treatment with the MDR inhibitor verapamil suggests that they are not MDR substrates. Compound 25 showed nanomolar antiproliferative potency. It severely disrupts the microtubule network in cells and arrests cells at the G2/M cell-cycle phase, thus confirming tubulin targeting. 25 triggered apoptotic cell death, and induced autophagy. Docking studies suggest binding in a distinct way to the colchicine site. These compounds are promising new antitumor agents acting on tubulin.We thank the people at Frigoríficos Salamanca S.A. slaughterhouse for providing us with the calf brains, “Servicio General de NMR” and “Servicio General de Espectrometría de Masas” of the University of Salamanca for equipment. M.G. acknowledges a predoctoral fellowship from the Junta de Castilla y León (ORDEN EDU/529/2017 de 26 de junio). M.O.-S. acknowledges a predoctoral fellowship from the IBSAL (IBpredoc17/00010). A.V.-B. acknowledges a predoctoral fellowship from the Spanish Ministerio de Educación, Cultura y Deporte (FPU15/02457). This research was funded by the Consejería de Educación de la Junta de Castilla y León (ORDEN EDU/529/2017 de 26 de junio, SA030U16, SA262P18 and SA116P20), co-funded by the EU’s European Regional Development Fund-FEDER, the Spanish Ministry of Science, Innovation and Universities (RTI2018-099474-BI00) and the health research program of the Instituto de Salud Carlos III (Spanish Ministry of Economy and Competitiveness) [PI16/01920 and PI20/01569] co-funded with FEDER funds. Ministerio de Educación, Cultura y Deporte [FPU15/02457], IBSAL [IBpredoc17/00010]

Microtubule Destabilizing Sulfonamides as an Alternative to Taxane-Based Chemotherapy

Pan-Gyn cancers entail 1 in 5 cancer cases worldwide, breast cancer being the most commonly diagnosed and responsible for most cancer deaths in women. The high incidence and mortality of these malignancies, together with the handicaps of taxanes—first-line treatments—turn the development of alternative therapeutics into an urgency. Taxanes exhibit low water solubility that require formulations that involve side effects. These drugs are often associated with dose-limiting toxicities and with the appearance of multi-drug resistance (MDR). Here, we propose targeting tubulin with compounds directed to the colchicine site, as their smaller size offer pharmacokinetic advantages and make them less prone to MDR efflux. We have prepared 52 new Microtubule Destabilizing Sulfonamides (MDS) that mostly avoid MDR-mediated resistance and with improved aqueous solubility. The most potent compounds, N-methyl-N-(3,4,5-trimethoxyphenyl-4-methylaminobenzenesulfonamide 38, N-methyl-N-(3,4,5-trimethoxyphenyl-4-methoxy-3-aminobenzenesulfonamide 42, and N-benzyl-N-(3,4,5-trimethoxyphenyl-4-methoxy-3-aminobenzenesulfonamide 45 show nanomolar antiproliferative potencies against ovarian, breast, and cervix carcinoma cells, similar or even better than paclitaxel. Compounds behave as tubulin-binding agents, causing an evident disruption of the microtubule network, in vitro Tubulin Polymerization Inhibition (TPI), and mitotic catastrophe followed by apoptosis. Our results suggest that these novel MDS may be promising alternatives to taxane-based chemotherapy in chemoresistant Pan-Gyn cancers.We thank the people at Frigoríficos Salamanca S.A slaughterhouse for providing us with the calf brains, “Servicio General de NMR” and “Servicio General de Espectrofotometría de Masas” of the University of Salamanca for equipment. M.G. acknowledges a predoctoral fellowship from the Junta de Castilla y León (ORDEN EDU/529/2017 de 26 de junio). M.O.-S. acknowledges a predoctoral fellowship from the IBSAL (IBpredoc17/00010). A.V.-B. acknowledges a predoctoral fellowship from the Spanish Ministerio de Educación, Cultura y Deporte (FPU15/02457). This research was funded by the Consejería de Educación de la Junta de Castilla y León (SA030U16, SA262P18 and SA116P20), co-funded by the EU’s European Regional Development Fund-FEDER, the Spanish Ministry of Science, Innovation and Universities (RTI2018-099474-BI00) and the health research program of the Instituto de Salud Carlos III (Spanish Ministry of Economy and Competitiveness, PI16/01920 and PI20/01569) co-funded with FEDER founds

Suppression of metastatic organ colonization and antiangiogenic activity of the orally bioavailable lipid raft-targeted alkylphospholipid edelfosine

Metastasis is the leading cause of cancer mortality. Metastatic cancer is notoriously difficult to treat, and it accounts for the majority of cancer -related deaths. The ether lipid edelfosine is the prototype of a family of synthetic antitumor compounds collectively known as alkylphospholipid analogs, and its antitumor activity involves lipid raft reorganization. In this study, we examined the effect of edelfosine on metastatic colonization and angiogenesis. Using non-invasive bioluminescence imaging and histological examination, we found that oral administration of edelfosine in nude mice significantly inhibited the lung and brain colonization of luciferaseexpressing 435-Lung-eGFP-CMV/Luc metastatic cells, resulting in prolonged survival. In metastatic 435 -Lung and MDA-MB-231 breast cancer cells, we found that edelfosine also inhibited cell adhesion to collagen -I and laminin-I substrates, cell migration in chemotaxis and wound -healing assays, as well as cancer cell invasion. In 435 -Lung and other MDA-MB-435-derived sublines with different organotropism, edelfosine induced G2/M cell cycle accumulation and apoptosis in a concentration- and time -dependent manner. Edelfosine also inhibited in vitro angiogenesis in human and mouse endothelial cell tube formation assays. The antimetastatic properties were specific to cancer cells, as edelfosine had no effects on viability in non -cancerous cells. Edelfosine accumulated in membrane rafts and endoplasmic reticulum of cancer cells, and membrane raft -located CD44 was downregulated upon drug treatment. Taken together, this study highlights the potential of edelfosine as an attractive drug to prevent metastatic growth and organ colonization in cancer therapy. The raft -targeted drug edelfosine displays a potent activity against metastatic organ colonization and angiogenesis, two major hallmarks of tumor malignancy

Introducción de la gamificación en la docencia en Química en las facultades de Farmacia y de Ciencias Agrarias y Ambientales

Memoria ID-0196. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2017-2018

Implementación del Trabajo Fin de Grado del Grado en Medicina

Memoria ID-0283. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2014-2015

The Masked Polar Group Incorporation (MPGI) Strategy in Drug Design: Effects of Nitrogen Substitutions on Combretastatin and Isocombretastatin Tubulin Inhibitors

[EN] Colchicine site ligands suffer from low aqueous solubility due to the highly hydrophobic nature of the binding site. A new strategy for increasing molecular polarity without exposing polar groups—termed masked polar group incorporation (MPGI)—was devised and applied to nitrogenated combretastatin analogues. Bulky ortho substituents to the pyridine nitrogen hinder it from the hydrophobic pocket while increasing molecular polarity. The resulting analogues show improved aqueous solubilities and highly potent antiproliferative activity against several cancer cell lines of different origin. The more potent compounds showed moderate tubulin polymerization inhibitory activity, arrested the cell cycle of treated cells at the G2/M phase, and subsequently caused apoptotic cell death represented by the cells gathered at the subG0/G1 population after 48 h of treatment. Annexin V/Propidium Iodide (PI) double-positive cells observed after 72 h confirmed the induction of apoptosis. Docking studies suggest binding at the colchicine site of tubulin in a similar way as combretastatin A4, with the polar groups masked by the vicinal substituents. These results validate the proposed strategy for the design of colchicine site ligands and open a new road to increasing the aqueous solubility of ligands binding in apolar environments

Elaboración de informes en formato de publicación científica

Memoria ID-0150. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2017-2018

Seguridad en el laboratorio. Revisión de la enseñanza práctica de la Química Orgánica en la Facultad de Farmacia

Memoria ID-136. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2018-2019

Adaptación de las clases prácticas de asignaturas de química a un modelo de semipresencialidad y optimización del tiempo de trabajo en laboratorio

Memoria ID-145 Ayudas de la Universidad de Salamanca para la innovación docente, curso 2020-2021