erteberel and Triple-Negative-Breast-Neoplasms

To identify regulators of triple-negative breast cancer (TNBC), gene expression profiles of malignant parts of TNBC (mTNBC) and normal adjacent (nadj) parts of the same breasts have been compared. We are interested in the roles of estrogen receptor β (ERβ) and the cytochrome P450 family (CYPs) as drivers of TNBC. We examined by RNA sequencing the mTNBC and nadj parts of five women. We found more than a fivefold elevation in mTNBC of genes already known to be expressed in TNBC: BIRC5/survivin, Wnt-10A and -7B, matrix metalloproteinases (MMPs), chemokines, anterior gradient proteins, and lysophosphatidic acid receptor and the known basal characteristics of TNBC, sox10, ROPN1B, and Col9a3. There were two unexpected findings: 1) a strong induction of CYPs involved in activation of fatty acids (CYP4), and in inactivation of calcitriol (CYP24A1) and retinoic acid (CYP26A1); and 2) a marked down-regulation of FOS, FRA1, and JUN, known tethering partners of ERβ. ERβ is expressed in 20 to 30% of TNBCs and is being evaluated as a target for treating TNBC. We used ERβ

Topics: Amphibian Proteins; Animals; Benzopyrans; Calcitriol; Cytochrome P-450 Enzyme System; Down-Regulation; Estrogen Receptor alpha; Estrogen Receptor beta; Fatty Acids; Female; Gene Expression Regulation, Neoplastic; Humans; Mice; Neoplasms, Experimental; Random Allocation; Survivin; Transcriptome; Tretinoin; Triple Negative Breast Neoplasms; Wnt Proteins

Metastases constitute the greatest causes of deaths from cancer. However, no effective therapeutic options currently exist for cancer patients with metastasis. Estrogen receptor β (ERβ), as a member of the nuclear receptor superfamily, shows potent tumor-suppressive activities in many cancers. To investigate whether modulation of ERβ could serve as a therapeutic strategy for cancer metastasis, we examined whether the selective ERβ agonist LY500307 could suppress lung metastasis of triple-negative breast cancer (TNBC) and melanoma. Mechanistically, while we observed that LY500307 potently induced cell death of cancer cells metastasized to lung in vivo, it does not mediate apoptosis of cancer cells in vitro, indicating that the cell death-inducing effects of LY500307 might be mediated by the tumor microenvironment. Pathological examination combined with flow cytometry assays indicated that LY500307 treatment induced significant infiltration of neutrophils in the metastatic niche. Functional experiments demonstrated that LY500307-treated cancer cells show chemotactic effects for neutrophils and that in vivo neutrophil depletion by Ly6G antibody administration could reverse the effects of LY500307-mediated metastasis suppression. RNA sequencing analysis showed that LY500307 could induce up-regulation of IL-1β in TNBC and melanoma cells, which further triggered antitumor neutrophil chemotaxis. However, the therapeutic effects of LY500307 treatment for suppression of lung metastasis was attenuated in

Topics: Animals; Antineoplastic Agents; Apoptosis; Benzopyrans; Cell Line, Tumor; Drug Screening Assays, Antitumor; Estrogen Receptor beta; Estrogen Receptor Modulators; Estrogens; Female; Immunity, Innate; Interleukin-1beta; Lung Neoplasms; Mammary Neoplasms, Experimental; Melanoma, Experimental; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Neoplasms, Hormone-Dependent; Neutrophil Infiltration; Neutrophils; Specific Pathogen-Free Organisms; Triple Negative Breast Neoplasms; Tumor Microenvironment