Identification of necrotic signaling pathways in heterotypic 3D cultures: evaluation of their influence on compounds with therapeutic potential against cancer

Abstract

Necroptosis is a form of cell death regulated caspase-independent and is performed by receptor-interacting serine/threonine protein kinase 1(RIPK1), RIPK3 and mixed lineage kinase domain-like protein (MLKL). Recently, cancer therapy based on necroptosis has been proposed as an innovative strategy for antitumor treatment. In research on the cytotoxicity of drugs as antitumor therapy, cell culture has been an important tool for biological research, since this type of culture system contributes to the reduction of the use of laboratory animal models. Among the cell culture models there are 3D models that have a wide application in pharmacological studies and in tumor biology, since the tumor microenvironment can be mimicked with co-culture of different cell types and components, such as stroma. Tumor stroma is a supportive tissue that surrounds the tumor, with fibroblasts being the largest cell population. Tumor-stroma interactions promote changes in cancer cells and tumor microenvironment, allowing for tumor progression, invasion and metastasis. It is known that drugs that promote cell death have a weak therapeutic effect on the inner regions of the spheroids (hypoxic region), since they are composed of senescent and necrotic cells. It is therefore of paramount importance to understand how these (necrotic) cells influence the efficacy of anticancer drugs, and whether this is related to the cell-cell, extracellular matrix-cell interaction or even to the expression of necroptosis genes present in those inner regions Of the tumor spheroids.Our research group has being evaluated the antiproliferative action of extracts of marine sponges and ascidians in tumor cells, and some compounds of them isolated, regarding their therapeutic potential in lung, breast and melanoma cancer. In this context it is of great importance to establish heterotypic 3D culture systems that simulate the heterogeneity of the tumor microenvironment, to evaluate the cytotoxicity of marine compounds in this type of culture, and the expression levels of RIPK1, RIPK3 and MLKL in treated cells; and it study whether the silencing of these genes would potentiate or not the therapeutic potential of these compounds.