Exploring new therapeutic targets and novel therapies for resistant colorectal cancer subtypes

Colorectal cancer (CRC) represents the fourth leading cause of death by cancer in the world. CRC treatment is determined according to disease stage. 5-fluoruracil (5-FU), oxaliplatin and Irinotecan are the main chemotherapeutic compounds used in CRC treatment in different therapeutic strategies. However, in most aggressive CRCs, cells often develop resistance mechanisms leading to ineffectiveness of these therapies. Thus, it is of great importance the better understanding of molecular mechanisms underlying CRC in order to find new therapeutic targets and novel therapeutic strategies for treating advanced and resistant CRC. Deregulation of Wnt/β-catenin and Sonic hedgehog/Gli (Shh/Gli) signaling pathways, among many others, has been implicated in CRC carcinogenesis and metastasis. Excessive activation of Wnt/β-catenin signaling stimulates CRC development through activation of downstream cancer-related targets. TCF7L2 gene, encoding the main transcriptional activator of this pathway, originates different TCF7L2 isoforms that have been implicated in CRC. Moreover, defective regulation of Shh/Gli pathway have been denoted for its significant role in CRC progression, affecting the regulation of a diversity of cell processes involved in CRC carcinogenesis. During metastasis, cells develop mesenchymal characteristics, through the epithelial-to-mesenchymal transition (EMT) process. Furthermore, there is an established link between cancer stem cells (CSCs) and metastasis. Therefore, the aim of this project was to explore new therapeutic targets and novel therapies for resistant colorectal cancer subtypes. By studying TCF7L2 gene expression in a cohort of 38 CRC patients and CRC representative cell lines, we identified differential expression of specific TCF7L2 isoforms, varying in exon inclusion within exons 1-5 and exons 11-17, that appear to differ among CRC patients’ samples and between normal and tumor tissues. Therefore, this opens the door for further investigation on differential expression of TCF7L2 isoforms and its relation to CRC tumorigenesis and eventually to CRC risk. In a second phase of the project we tested a panel of 10 different compounds (cytostatic drugs used in conventional CRC treatment, epigenetic modulators, targeted therapies of specific signaling pathways and nutraceuticals) and the most promising combinations between them, for anti-proliferative and anti-migratory activities, in two CRC cell lines representative of mucinous tumors resistant to therapy (HT-29 and LS174T). The most promising combinations were evaluated for their effect in the expression of gene markers involved in cell-cycle, CRC stemness, epithelial-mesenchymal transition and Wnt/β-catenin and Sonic hedgehog/Gli (Shh/Gli) signaling pathways. With this work we were able to identify promising therapy combinations for the treatment of resistant CRC subtypes and explore the potential of new compounds as complement for conventional therapy in treatment of aggressive forms of CRC

An Overview

Funding Information: Funding: This work was supported by FCT–Fundação para a Ciência e a Tecnologia (grants UIDB/04567/2020 and UIDP/04567/2020 to CBIOS, PTDC/BIA-MOL/31104/2017, and PhD grants 2020.07813.BD to Í.G. and 2020.04630.BD to D.C.). C.F.-P. and R.M. are funded by FCT Scientific Employment Stimulus contract with the reference numbers CEEC/CBIOS/NUT/2018 and CEEC/04567/CBIOS/2020, respectively. Authors also acknowledge COFAC/ILIND–Cooperativa De Formação E Animação Cultural CRL/Instituto Lusófono de Investigação e Desenvolvimento (grant COFAC/ILIND/CBIOS/2/2021). Authors also acknowledge the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 804229. iNOVA4Health Research Unit (LISBOA-01-0145-FEDER-007344), which is co-funded by FCT/Ministério da Ciência e do Ensino Superior, through national funds, and by FEDER under the PT2020 Partnership Agreement.Kidney diseases constitute a worldwide public health problem, contributing to morbidity and mortality. The present study aimed to provide an overview of the published data regarding the potential beneficial effects of polyphenols on major kidney diseases, namely acute kidney injury, chronic kidney disease, diabetic nephropathy, renal cancer, and drug-induced nephrotoxicity. This study consists of a bibliographical review including in vitro and in vivo studies dealing with the effects of individual compounds. An analysis of the polyphenol metabolome in human urine was also conducted to estimate those compounds that are most likely to be responsible for the kidney protective effects of polyphenols. The biological effects of polyphenols can be highly attributed to the modulation of specific signaling cascades including those involved in oxidative stress responses, anti-inflammation processes, and apoptosis. There is increasing evidence that polyphenols afford great potential in renal disease protection. However, this evidence (especially when in vitro studies are involved) should be considered with caution before its clinical translation, particularly due to the unfavorable pharmacokinetics and extensive metabolization that polyphenols undergo in the human body. Future research should consider polyphenols and their metabolites that indeed reach kidney tissues.publishersversionpublishe

The Dietary Isothiocyanate Erucin Reduces Kidney Cell Motility by Disturbing Tubulin Polymerization

Scope: Epidemiological evidence associates the consumption of cruciferous vegetables with reduced risk of several cancers, including renal cell carcinoma. Erucin can be generated by in vivo reduction of sulforaphane or by enzymatic hydrolysis of glucoerucin. Contrarily to sulforaphane, only limited studies have addressed the anticancer properties of erucin. This study aims at evaluating the impact of erucin on renal cell biology. Methods and Results: The effects of erucin were assessed in 786-O and Vero-E6 cells, representative of human renal cancer and non- cancer kidney cells, respectively. Erucin induced a concentration-dependent decrease in cell viability and cell cycle arrest at G2/Mitosis. In Vero-E6 cells erucin modestly reduced intracellular reactive oxygen species levels while in 786-O no effects were detected. After erucin treatment, both cell lines revealed altered morphology, with a concentration-dependent change from an elongated shape towards a smaller round conformation. Moreover, erucin affected cell adhesion and strongly altered the tubulin network structure and specifically microtubule polymerization. These results are in line with the observed decrease in collective and single cell migration and G2/Mitosis arrest. Conclusions: Overall, erucin may have a beneficial impact in reducing the motility of renal cancer cells. Our results contribute to explore possible dietary approaches for secondary/tertiary renal cancer chemoprevention