Project description:The objective of these experiments is to identify novel direct and indirect targets of miR-150-5p in breast cancer cell lines. The goal is that these will give direction as to what targets or pathways may be contributing to the reduced growth observed in these cell lines upon restoration of miR-150-5p. A therapy directed towards one or more critical subtype-specific targets could be developed as a therapeutic for breast cancer patients. Using has-miR-150-5p mirVana miRNA mimic (Ambion, 4464066), miR-150-5p was restored to an estrogen receptor positive breast cancer cell line, ZR-75-1.
Project description:The origin and the contribution of breast tumor heterogeneity to its progression are not clear. We investigated the effect of a growing orthotopic tumor formed by an aggressive estrogen receptor (ER)-negative breast cancer cell line on the metastatic potential of a less aggressive ER-positive breast cancer cell line for the elucidation of how the presence of heterogeneous cancer cells might affect each other’s metastatic behavior. ER positive ZR-75-1/GFP/puro cells, resistant to puromycin and non-tumorigenic/non-metastatic without exogenous estrogen supplementation, were injected intracardiacally into mice bearing growing orthotopic tumors, formed by ER negative MDA-MB-231/GFP/Neo cells resistant to G418. A variant cell line B6, containing both estrogen-dependent and -independent cells, were isolated from GFP expressing cells in the bone marrow and re-inoculated in nude mice to generate an estrogen-independent cell line B6TC.
Project description:Patients with advanced colorectal cancer (CRC) are commonly treated with systemic combination therapy but suffer eventually from drug resistance. MicroRNAs (miRNAs) are suggested to play a role in treatment resistance of CRC. We studied whether restoring downregulated miR-195-5p and 497-5p sensitize CRC cells to currently used chemotherapeutics 5-fluorouracil, oxaliplatin and irinotecan. Sensitivity to 5-FU, oxaliplatin and irinotecan before and after transfection with miR-195-5p and miR-497-5p mimics was analyzed in CRC cell lines HCT116, RKO, DLD-1 and SW480. Mass spectrometry based proteomic analysis of transfected and wild-type cells was used to identify targets involved in sensitivity to chemotherapy. Proteomic analysis revealed 181 proteins with significantly altered expression after transfection with miR-195-5p mimic in HCT116 and RKO, including 118 downregulated and 63 upregulated proteins. After transfection with miR-497-5p mimic, 130 proteins were significantly downregulated and 102 were upregulated in HCT116 and RKO (P<0.05 and FC<-3 or FC>3). CHUK and LUZP1 were coinciding downregulated proteins in sensitized CRC cells after transfection with either mimic. Resistance mechanisms of these two proteins may be related to nuclear factor kappa-B signaling and G1 cell cycle arrest, respectively. Restoring miR-195-5p and miR-497-5p expression enhanced sensitivity to chemotherapy, mainly oxaliplatin, in CRC cells and could be a promising treatment strategy for patients with mCRC. Proteomics revealed potential targets of these miRNAs involved in sensitivity to chemotherapy.
Project description:The Androgen Receptor is a Tumor Suppressor in Estrogen Receptor Positive Breast Cancer [ZR-75-1 cell line Bicalutamide study ER ChIP-seq]
Project description:The objective of these experiments is to identify novel direct and indirect targets of miR-150-5p in breast cancer cell lines. The goal is that these will give direction as to what targets or pathways may be contributing to the reduced growth observed in these cell lines upon restoration of miR-150-5p. A therapy directed towards one or more critical subtype-specific targets could be developed as a therapeutic for breast cancer patients. Using has-miR-150-5p mirVana miRNA mimic (Ambion, 4464066), miR-150-5p was restored to a triple negative breast cancer cell line, BT-549.
