Evaluation of chemotherapy and P2Et extract combination in ex-vivo derived tumor mammospheres from breast cancer patients

Abstract

The main cause of death by cancer is metastasis rather than local complications of primary tumors. Recent studies suggest that breast cancer stem cells (BCSCs), retains the ability to self-renew and differentiate to repopulate the entire tumor, also, they have been associated with resistance to chemotherapy and tumor recurrence, even after tumor resection. Chemotherapy has been implicated in the induction of resistant phenotypes with highly metastatic potential. Naturally occurring compounds, especially phytochemicals such as P2Et, can target different populations of cancer cells as well as BCSC, favoring the activation of immune response via immunogenic tumor death. Here, we evaluated the presence of BCSC as well as markers related to drug resistance in tumors obtained from 78 patients who had received (or not) chemotherapy before surgery. We evaluated the ex vivo response of patient tumor-derived organoids (or mammospheres) to chemotherapy alone or in combination with P2Et. A xenotransplant model engrafted with MDA-MB-468 was used to evaluate in vivo the activity of P2Et, in this model P2Et delay tumor growth. We show that patients with luminal and TNBC, and those who received neoadjuvant therapy before surgery have a higher frequency of BCSC. Further, the treatment with P2Et in mammospheres and human breast cancer cell lines improve the in vitro tumor death and decrease its viability and proliferation together with the release of immunogenic signals. P2Et could be a good co-adjuvant in antitumor therapy in patients, retarding the tumor growth by enabling the activation of the immune response.

The breast cancer immune microenvironment is modified by neoadjuvant chemotherapy

“…Interestingly, there is an association between the immune cluster and the number of stem cell/epithelial–mesenchymal transition (EMT)-related gene signatures 15 . In a previous study by our group, we observed an accumulation of tumor cells of the ALDH + stem phenotype in response to NAT in all molecular subtypes except Her-2 16 . This finding suggests that the intrinsic differences of tumors may also play a role in the control of the microenvironment, as previously reported 17 – 19 .…”

The Breast Cancer Immune Microenvironment is Modified by Neoadjuvant Chemotherapy

“…Interestingly, there is an association between the immune cluster and the number of stem cell/epithelial-mesenchymal transition (EMT)related gene signatures 15 . In a previous study by our group, we observed an accumulation of tumor cells of the ALDH + stem phenotype in response to NAT in all molecular subtypes except Her-2 16 . This finding suggests that the intrinsic differences of tumors may also play a role in the control of the microenvironment, as previously reported [17][18][19] .…”

Plant-derived extracts and metabolic modulation in leukemia: a promising approach to overcome treatment resistance

“…The central research area of our group is the study and development of phytomedicines from Colombian plants, among them Petiveria alliacea (P. alliacea), Caesalpinia spinosa (C. spinosa), Tillandsia usneoides (T. usneoides), and Piper nigrum (P. nigrum) (Lasso et al, 2018;Urueña et al, 2020;Lasso et al, 2022;Urueña et al, 2022). Each one of the extracts of these plants has been characterized from a chemical point of view, and the main compounds have been isolated and studied.…”