ver-155008 and Breast-Neoplasms

TNFα is a pleiotropic cytokine which fuels tumor cell growth, invasion, and metastasis in some malignancies, while in others it induces cytotoxic cell death. However, the molecular mechanism by which TNFα exerts its diverse effects on breast cancer subtypes remains elusive. Using in vitro assays and mouse xenografts, we show here that TNFα contributes to the aggressive properties of triple negative breast cancer (TNBC) cell lines via upregulation of TNFAIP3(A20). In a striking contrast, TNFα induces a potent cytotoxic cell death in luminal (ER+) breast cancer cell lines which fail to upregulate A20 expression. Overexpression of A20 not only protects luminal breast cancer cell lines from TNFα-induced cell death via inducing HSP70-mediated anti-apoptotic pathway but also promotes a robust EMT/CSC phenotype by activating the pStat3-mediated inflammatory signaling. Furthermore, A20 overexpression in luminal breast cancer cells induces aggressive metastatic properties in mouse xenografts via generating a permissive inflammatory microenvironment constituted by granulocytic-MDSCs. Collectively, our results reveal a mechanism by which A20 mediates pleiotropic effects of TNFα playing role in aggressive behaviors of TNBC subtype while its deficiency results in TNFα-induced apoptotic cell death in luminal breast cancer subtype.

Topics: Animals; Apoptosis; Breast Neoplasms; Cell Line, Tumor; Epithelial-Mesenchymal Transition; Female; Gene Expression Regulation, Neoplastic; Genetic Pleiotropy; Heterografts; HSP72 Heat-Shock Proteins; Humans; Inflammation; Lung Neoplasms; Mice; Mice, Inbred NOD; Mice, SCID; Neoplasm Invasiveness; Neoplasm Proteins; Neoplastic Stem Cells; Purine Nucleosides; Recombinant Fusion Proteins; RNA, Neoplasm; Signal Transduction; STAT3 Transcription Factor; Triple Negative Breast Neoplasms; Tumor Necrosis Factor alpha-Induced Protein 3; Tumor Necrosis Factor-alpha

Heat shock protein 70 has been recognized as a target for anticancer therapy. The overexpression of heat shock protein 70 is observed frequently in several types of tumors, including breast cancer. It is involved with increased cell proliferation, poor prognosis, and drug resistance in breast cancer. VER-155008 is an effective inhibitor of heat shock protein 70 that targets the adenosine triphosphatase-binding domain of heat shock protein 70. In this study, the effects of VER-155008, heat shock (43°C, 1 hour), and the combination treatment of VER-155008 and heat shock on the mitochondria of the MCF-7 breast cancer cells were investigated through a laser scanning microscope combined with mitochondrial membrane potential fluorescence probe. We observed broken mitochondria networks, decreased mitochondrial membrane potential, and cell size. The mitochondrial contents were reduced with the VER-155008 treatment and the combination treatment of VER-155008 and heat shock. The effects of the inhibition presented treatment time dependence. Moreover, the effect of the inhibition of the sole VER-155008 was alleviated when it was combined with heat shock although there was no obvious change with the sole heat shock treatment. The results indicated that VER-155008, the inhibitor of heat shock protein 70, induced apoptosis in MCF-7 breast cancer cells whatever it was in the sole or the combined manner, and its promoting apoptosis effect could be alleviated by heat shock. Our findings demonstrated that HSP70 can be a good target for developing breast cancer therapy.

Topics: Apoptosis; Breast Neoplasms; Cell Proliferation; Female; Heat-Shock Response; HSP70 Heat-Shock Proteins; Humans; MCF-7 Cells; Microscopy, Confocal; Purine Nucleosides

HSP70 is a potential target for tumour treatment. HSP70 plays significant roles in several biological processes, including the regulation of apoptosis. In this study, piperidine derivatives were designed as novel HSP70 inhibitors based on virtual fragment screening performed in Dock 4.0, Discovery Studio 2.5 and SYBYL 6.9. A total of 67 novel piperidine derivatives were synthesized. Cell viability assays were performed in 16 cancer cell lines. The emphasis was placed on lapatinib-resistant breast cancer cells (BT/Lap(R)1.0, MDA-MB-361, SK/Lap(R)1.0, and MDA-MB-453). The compounds HSP70-36/37/40/43/46 significantly inhibited the proliferation of human breast cancer cells. Compound HSP70-36 inhibited the growth of BT474 and BT/Lap(R)1.0 cells with IC50 values of 1.41 μM and 1.47 μM, respectively. The binding affinity of HSP70-36/HSP70 was evaluated by surface plasmon resonance and yielded Kd values of 2.46 μM. The LD50 was 869.0 mgkg(-1). These data suggest that HSP70-36 may be a potential candidate compound for tumour treatment.

Topics: Binding Sites; Breast Neoplasms; Cell Line, Tumor; Computer Simulation; Drug Design; Drug Resistance, Neoplasm; Female; HSP70 Heat-Shock Proteins; Humans; Inhibitory Concentration 50; Models, Molecular; Piperidines

The objective of this study was to synthesize a nanocomposite, aptamer-gold nanoparticle-hybridized graphene oxide (Apt-AuNP-GO), to facilitate targeted treatment of tumor cells by near-infrared (NIR) light-activatable photothermal therapy. We also investigated whether Apt-AuNP-GO with NIR illumination modulates heat shock proteins (HSPs) expression leading to therapeutic response in human breast cancer cells. These findings can provide strategies for improving the photothermal therapy efficacy of cancer. The self-assembled Apt-AuNP-GO nanocomposite could selectively target MUC1-positive human breast cancer cells (MCF-7) due to the specific interaction between the MUC1-binding-aptamer and the MUC1 (type I transmembrane mucin glycoprotein) on cell membrane. In addition, Apt-AuNP-GO has a high light-to-heat conversion capability for photoabsorption of NIR light, and it is able to exert therapeutic effects on MCF-7 cells at an ultralow concentration without inducing adverse effects in healthy cells. The Apt-AuNP-GO nanocomposites combine the advantages of GOs, AuNPs, and Apts, possess specific targeting capability, excellent biocompatibility, and tumor cell destruction ability, suggesting great potential for application in the photothermal therapy of breast cancer. Under NIR illumination, Apt-AuNP-GO induced transient increase in HSP70 expression, which decreased thereafter. This phenomenon may cause irreversible damage to Apt-AuNP-GO-treated MCF-7 cell under NIR illumination. We also demonstrated that the combination therapy of heat and HSP70 inhibitor could synergistically generate marked tumoricidal effects against breast cancer. These results suggest that the degree and duration of HSP70 protein expression are correlated with therapeutic effects against breast cancer for Apt-AuNP-GO-assisted photothermal therapy. We believe that such a nanocomposite can be readily extended to the construction of HSP70 inhibitors-loaded Apt-AuNP-GO, which could deliver both heat and HSP70 inhibitors to tumorigenic regions for the chemo-photothermal therapy.

Topics: Apoptosis Regulatory Proteins; Aptamers, Nucleotide; Breast Neoplasms; Cell Survival; Female; Gold; Graphite; HSP70 Heat-Shock Proteins; Human Umbilical Vein Endothelial Cells; Humans; Infrared Rays; MCF-7 Cells; Metal Nanoparticles; Microscopy, Fluorescence; Mucin-1; Nanocomposites; Oxides; Phototherapy; Purine Nucleosides; Rhodamines; Temperature

The anti-apoptotic function of the 70 kDa family of heat shock proteins and their role in cancer is well documented. Dual targeting of Hsc70 and Hsp70 with siRNA induces proteasome-dependent degradation of Hsp90 client proteins and extensive tumor specific apoptosis as well as the potentiation of tumor cell apoptosis following pharmacological Hsp90 inhibition.. We have previously described the discovery and synthesis of novel adenosine-derived inhibitors of the 70 kDa family of heat shock proteins; the first inhibitors described to target the ATPase binding domain. The in vitro activity of VER-155008 was evaluated in HCT116, HT29, BT474 and MDA-MB-468 carcinoma cell lines. Cell proliferation, cell apoptosis and caspase 3/7 activity was determined for VER-155008 in the absence or presence of small molecule Hsp90 inhibitors.. VER-155008 inhibited the proliferation of human breast and colon cancer cell lines with GI(50)s in the range 5.3-14.4 microM, and induced Hsp90 client protein degradation in both HCT116 and BT474 cells. As a single agent, VER-155008 induced caspase-3/7 dependent apoptosis in BT474 cells and non-caspase dependent cell death in HCT116 cells. VER-155008 potentiated the apoptotic potential of a small molecule Hsp90 inhibitor in HCT116 but not HT29 or MDA-MB-468 cells. In vivo, VER-155008 demonstrated rapid metabolism and clearance, along with tumor levels below the predicted pharmacologically active level.. These data suggest that small molecule inhibitors of Hsc70/Hsp70 phenotypically mimic the cellular mode of action of a small molecule Hsp90 inhibitor and can potentiate the apoptotic potential of a small molecule Hsp90 inhibitor in certain cell lines. The factors determining whether or not cells apoptose in response to Hsp90 inhibition or the combination of Hsp90 plus Hsc70/Hsp70 inhibition remain to be determined.

Topics: Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Breast Neoplasms; Caspase 3; Caspase 7; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Drug Delivery Systems; Drug Synergism; Female; HSC70 Heat-Shock Proteins; HSP70 Heat-Shock Proteins; HSP90 Heat-Shock Proteins; Humans; Purine Nucleosides