Biology subjects

Acconcia, F.

Publications and source records attributed to Acconcia, F..

4 recordsLinked to original sources

bioRxiv2023

Selective Impact of ALK and MELK Inhibition on ERα Stability and Cell Proliferation in Cell Lines Representing Distinct Molecular Phenotypes of Breast Cancer

Breast cancer (BC) is a leading cause of global cancer-related mortality in women, necessitating accurate tumor classification for timely intervention. Molecular and histological factors, including PAM50 classification, estrogen receptor (ER), breast cancer type 1 susceptibility protein (BRCA1), progesterone receptor (PR), and HER2 expression, contribute to intricate BC subtyping. Through in silico screenings and multiple BC cell line investigations, we identified enhanced sensitivity of ER-positive BC cell lines to ALK and MELK inhibitors, inducing ER degradation and diminishing proliferation in specific BC subtypes. MELK inhibition attenuated ER transcriptional activity, impeding E2-induced gene expression, and hampering proliferation in MCF-7 cells. Synergies between MELK inhibition with 4OH-tamoxifen (Tam) and ALK inhibition with HER2 inhibitors revealed potential therapeutic avenues for ER-positive/PR-positive/HER2-negative and ER-positive/PR-negative/HER2-positive tumors, respectively. Our findings propose MELK as a promising target for ER-positive/PR-positive/HER2-negative BC and highlight ALK as a potential focus for ER-positive/PR-negative/HER2-positive BC. The synergistic anti-proliferative effects of MELK with Tam and ALK with HER2 inhibitors underscore kinase inhibitors potential for selective treatment in diverse BC subtypes, paving the way for personalized and effective therapeutic strategies in BC management.

cancer biology↗

bioRxiv2019

Real-time measurement of E2:ERα transcriptional activity in live-cells.

Kinetic analyses of diverse physiological processes have the potential to unveil new aspects of the molecular regulation of cell biology at temporal levels. 17{beta}-estradiol (E2) regulates diverse physiological effects by binding to the estrogen receptor (ER), which primarily works as a transcription factor. Although many molecular details of the modulation of ER transcriptional activity have been discovered including the impact of receptor plasma membrane localization and its relative E2-evoked signalling, the knowledge of real-time ER transcriptional dynamics in living cells is lacking. Here, we report the generation of MCF-7 and HeLa cells stably expressing a modified luciferase under the control of an E2-sensitive promoter, which activity can be continuously monitored in living cells and show that E2 induces a linear increase in ER transcriptional activity. Ligand-independent (e.g., epidermal growth factor) receptor activation was also detected in a time-dependent manner. Kinetic profiles of ER transcriptional activity measured in the presence of both receptor antagonists and inhibitors of ER plasma membrane localization reveals a biphasic dynamic of receptor behaviour underlying novel aspects of receptor-regulated transcriptional effects. Finally, analysis of the rate of the dose-dependent E2 induction of ER transcriptional activity demonstrates that low doses of E2 induce an effect identical to that determined by high concentrations of E2 as a function of the duration of hormone administration. Overall, we present the characterization of sensitive stable cell lines where to study the kinetic of E2 transcriptional signaling and to identify new aspects of ER function in different physiological or pathophysiological conditions.

physiology↗

bioRxiv2018

In silico screening for ERα downmodulators identifies thioridazine as an anti-proliferative agent in primary, 4OH-tamoxifen-resistant and Y537S ERα-expressing breast cancer cells

PurposeMost breast cancers (BCs) express estrogen receptor (ER) and are treated with the endocrine therapy (ET) drugs 4OH-tamoxifen (Tam) and fulvestrant (i.e., ICI182,780-ICI). Unfortunately, a high fraction of ET-treated women relapses and become resistant to ET. Therefore, additional anti-BC drugs are needed. Recently, we proposed that the identification of novel anti-BC drugs can be achieved using the modulation of the ER intracellular content in BC cells as a pharmacological target. Here, we searched for Food and Drug Administration (FDA)-approved drugs that potentially modify the ER content in BC cells.\n\nMethodsWe screened in silico more than 60,000 compounds to identify FDA-approved drugs with a gene signature similar to that of ICI. We identified mitoxantrone and thioridazine and tested them in primary, Tam-resistant and genome-edited Y537S ER-expressing BC cells.\n\nResultsMitoxantrone and thioridazine induced ER downmodulation and prevented MCF-7 cell proliferation. Interestingly, while mitoxantrone was toxic for normal breast cells, thioridazine showed preferential activity toward BC cells. Thioridazine also reduced the ER content and prevented cell proliferation in primary, Tam-resistant and genome-edited Y537S ER-expressing BC cells.\n\nConclusionsWe suggest that the modulation of the ER intracellular concentration in BC cells can also be robustly exploited in in silico screenings to identify anti-BC drugs and further demonstrate a re-purposing opportunity for thioridazine in primary and metastatic ET-resistant BC treatment.

cancer biology↗

bioRxiv2017

A Functional Drug Re-Purposing Screening Identifies Carfilzomib As A Drug Preventing 17β-Estradiol: ERα Signaling And Cell Proliferation In Breast Cancer Cells

Most cases of breast cancer (BC) are estrogen receptor -positive (ER+) at diagnosis. The presence of ER drives the therapeutic approach for this disease, which often consists of endocrine therapy (ET). 4OH-Tamoxifen and faslodex (i.e., fulvestrant - ICI182,780) are two ETs that render tumor cells insensitive to 17{beta}-estradiol (E2)-dependent proliferative stimuli and prevent BC progression. However, ET has limitations and serious failures in different tissues and organs. Thus, there is an urgent need to identify novel drugs to fight BC in the clinic. Re-positioning of old drugs for new clinical purposes is an attractive alternative for drug discovery. For this analysis, we focused on the modulation of intracellular ER levels in BC cells as target for the screening of about 900 Food and Drug Administration (FDA) approved compounds that would hinder E2:ER signaling and inhibit BC cell proliferation. We found that carfilzomib induces ER degradation and prevents E2 signaling and cell proliferation in two ER+ BC cell lines. Remarkably, the analysis of carfilzomib effects on a cell model system with an acquired resistance to 4OH-tamoxifen revealed that this drug has an antiproliferative effect superior to faslodex in BC cells. Therefore, our results identify carfilzomib as a drug preventing E2:ER signaling and cell proliferation in BC cells and suggest its possible re-position for the treatment of ER+ BC as well as for those diseases that have acquired resistance to 4OH-tamoxifen.

cancer biology↗