afimoxifene and Triple-Negative-Breast-Neoplasms

Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer (BC) and lacks targeted therapy and alternate therapeutic combinations. There is a necessity to increase disease-free survival in patients particularly within the first 5 years of diagnosis. 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone (Z285), a novel 1,4 naphthoquinone analog, has been shown to have cytotoxic activity in BC cell lines and in combination with 4-hydroxytamoxifen (4-OHT). A known metabolite of tamoxifen, was postulated to decrease cell proliferation. Thus, this study investigates the use of Z285 and 4-OHT alone or in combination as a novel therapeutic alternative for TNBC.. Cell proliferation assays were performed on MDA-MB-231, Hs578T, MCF7 and HCC1806 cell lines at varying time points with Z285 and 4-OHT alone and in combination. Furthermore, ROS activity was measured to determine the changes in oxidative stress caused by both drugs.. The results showed dose- and time-dependent decreases in proliferation for all cell lines when treated with Z285, 4-OHT and their combination. Combinatorial analysis performed at 72 h using Synergyfinder. These promising results suggest the independent ability of each compound as a stand-alone chemotherapeutic agent, or in combinatorial therapy for the treatment of TNBC.

Topics: Apoptosis; Cell Line, Tumor; Cell Survival; Drug Synergism; Female; Humans; Inhibitory Concentration 50; Naphthoquinones; Reactive Oxygen Species; Tamoxifen; Triple Negative Breast Neoplasms

The ability to assess toxicant exposures of 3D in vitro mammary models that recapitulate the tissue microenvironment can aid in our understanding of environmental exposure risk over time. Longitudinal studies of 3D model systems, however, are cumbersome and suffer from a lack of high-throughput toxicological assays. In this study, we establish a noninvasive and label-free optical coherence tomography (OCT)-based imaging platform for tracking exposure-response relationships in 3D human mammary epithelial organoid models. The OCT-based assay includes metrics that quantify organoid intracellular kinetic energy and cross-sectional area (CSA). We compare the results to those obtained using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) mitochondrial dye conversion assay. Both estrogen receptor (ER)-positive (MCF7) and ER-negative (MCF10DCIS.com) breast cell lines were studied, beginning one hour after exposure and continuing for several days. Six days of exposure to 17β-estradiol or the selective ER modulator 4-hydroxytamoxifen respectively increased or decreased MCF7 organoid CSA (p < .01), consistent with the role of estrogen signaling in ER-positive mammary epithelial cell proliferation. We also observed a significant decrease in the intracellular kinetic energy of MCF10DCIS.com organoids after 24 h of exposure to doxorubicin, a cytotoxic intercalating agent that causes DNA double-strand breaks (p < .01). MTT-based metabolic activity of MCF10DCIS.com organoids after 48 h of doxorubicin exposure decreased with dose in a similar manner as OCT-based energy metrics. These results demonstrate the feasibility of an OCT-based assay to quantify mammary epithelial cell toxicant response in vitro, noninvasively, longitudinally, and in the context of tissue microenvironments, providing a new high-throughput screening tool for toxicological studies.

Topics: Cell Culture Techniques; Cell Death; Cell Proliferation; Dose-Response Relationship, Drug; Doxorubicin; Endocrine Disruptors; Estradiol; Humans; Mammary Glands, Human; MCF-7 Cells; Organoids; Precancerous Conditions; Receptors, Estrogen; Tamoxifen; Time Factors; Tomography, Optical Coherence; Triple Negative Breast Neoplasms

Triple negative breast cancer (TNBC) is the hardest breast cancer subtype to treat due to lacking therapeutic target and treatment options. In this study, we found that SLUG expression was much higher in TNBC MDA-MB-231 cells than estrogen receptor alpha (ERα) positive breast cancer MCF7 cells. 4-hydroxytamoxifen (4-OHT) promoted SLUG expression, which was blocked by curcumin. Further investigation showed that SLUG activated the transcription of hexokinase-2 (HK2) by binding to HK2 promoter. SLUG knockdown inhibited HK2 expression and weakened 4-OHT resistance of MDA-MB-231 cells. Conversely, SLUG overexpression elevated HK2 level and increased 4-OHT resistance of MCF7 cells. Combination of curcumin and 4-OHT suppressed SLUG and HK2 expression, leading to mitochondrion-mediated apoptosis. These results suggested SLUG as a potential target and curcumin as a promising natural agent for overcoming 4-OHT resistance of TNBC.

Topics: Antineoplastic Agents; Apoptosis; Base Sequence; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Cell Survival; Chromatin Immunoprecipitation; Curcumin; Drug Resistance, Neoplasm; Estrogen Receptor alpha; Female; Flow Cytometry; Glycolysis; Hexokinase; Humans; Mitochondria; Molecular Sequence Data; Promoter Regions, Genetic; Snail Family Transcription Factors; Tamoxifen; Transcription Factors; Triple Negative Breast Neoplasms

Triple-negative breast cancers (TNBC) represent the most aggressive form of breast cancers and their treatment are challenging due to the tumor heterogeneity. The high death rate and the limited systemic treatment options for TNBC necessitate the search for alternative chemotherapeutics. We previously found that FcOHTAM, an organometallic derivative of hydroxytamoxifen, showed in vitro a strong antiproliferative effect on various breast cancer cell lines, including MDA-MB-231 cells, the archetype of TNBC. In this study, we developed stealth FcOHTAM loaded lipid nanocapsules (LNCs) to further evaluate this novel drug on a TNBC xenografted model. Cell cycle analysis of MDA-MB-231 cells confirmed the preservation of the drug activity through LNCs causing a cycle arrest in phase S after 48 h exposure at the IC50 concentration (2 μm). Two intraperitoneal injections of FcOHTAM loaded LNCs (20 mg/kg) administered to luciferase-transfected MDA-MB-231 tumors bearing mice led to a marked delay in tumor growth. As a consequence, a significantly lower tumor volume was obtained at the end of the experiment with a difference of 36% at day 38 compared to the untreated group. These results represent the first evidence of an in vivo effect of FcOHTAM and ferrocenyl derivatives in general on xenografted breast tumors.

Topics: Animals; Antineoplastic Agents, Hormonal; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Female; Humans; Luminescent Measurements; Mice; Mice, SCID; Molecular Structure; Nanocapsules; Tamoxifen; Triple Negative Breast Neoplasms