Project description:The telomeric amplicon at 8p12 is common in ER+ breast cancers. Array-CGH and expression analyses of 1172 tumors revealed ZNF703/Zeppo1 was the single gene within the minimal amplicon and was amplified predominantly in the Luminal B subtype. Amplification was shown to correlate with increased gene and protein expression and was associated with a distinct expression signature and poor outcome. In the luminal MCF-7 cell line manipulation of ZNF703 expression altered transcription of genes also present within the primary tumor signature, including TGFBR2 (whose promoter was bound by ZNF703). Overexpression of ZNF703 rendered MCF-7 cells insensitive to TGFβ-induced suppression of mammosphere formation. Forced overexpression of ZNF703 in normal human breast epithelial cells enhanced the frequency of in vitro colony-forming cells from luminal progenitors. Together these data strongly point to ZNF703/Zeppo1 as a novel oncogene in Luminal B breast cancer. MCF-7 breast cancer cell line was infected with ZNF703 overexpression (ZNF703) or control (HIV) virus and following GFP sorting of infected cells, were transfected with control siRNA (siC) or siRNA against endogenous ZNF703 (siZNF), resulting in four different conditions: siC_HIV, siC_ZNF, siZNF_HIV and siZNF-ZNF. RNA for each condition was harvested from triplicate plates.
Project description:Examination of effect of stable DDR1 knockdown by shRNA on transcriptional profile in BXPC3 cell line to understand role of DDR1 in tumorigenesis. Transcriptional profiles of parental BXPC3 cell line was compared to BXPC3 cells stably transfected with non-target shRNA or DDR1 shRNA, N=3 for each condition.
Project description:Tumor proliferation, drug resistance and cell stemness are major difficulties that are encountered during breast cancer therapy and are often responsible for disease progression and cancer-related mortality. β-catenin is considered to be an invasion gene in breast cancer. However, how β-catenin regulates breast cancer cell proliferation and stemness remains unclear. In the present study, β-catenin knockdown by small interfering RNA in MDA-MB-468, a highly metastatic breast cancer cell line, inhibited the expression of β-catenin, Oct3/4 (stemness), survivin (anti-apoptosis) and BCRP (drug resistance). Knockdown of β-catenin enhanced the effects of fluorouracil (5-FU) chemotherapy on the proliferation of MDA-MB-468 cells. Thus, these preliminary results indicate that β-catenin knockdown enhanced 5-FU-induced proliferation inhibition in the breast cancer cell line MDA-MB-468, and indicate that combining 5-FU with gene silencing could be an advantageous option for enhancing the curative effect of chemotherapy in breast cancer and other malignancies.
Project description:Cisplatin treatment confers the relative resistance to MCF-7 cells as compared to other breast cancer cell lines. One principal reason is that chemotherapeutic agents induce autophagy in these cells to inhibit apoptosis. Binding immunoglobulin protein (BiP), a master regulator of unfolded protein response (UPR) and 14-3-3ζ are two critical proteins upregulated in breast cancer rendering resistance to anticancer drugs. They also play pivotal roles in autophagy with crosstalk with the apoptotic pathways of UPR through certain regulators. Thus, BiP and 14-3-3ζ were selected as the candidate targets to enhance cell death and apoptosis. First, cisplatin resistance was induced and determined by MTT assay and qPCR in MCF-7 cells. Then, the apoptosis axis of UPR was activated by knocking down either BiP or 14-3-3ζ and overactivated by co-knockdown of BiP and 14-3-3ζ. Apoptosis assays were performed using flow cytometry, TUNEL assays utilized confocal microscopy followed by western blot analysis and caspase-3 and JNK activities were investigated to assess the outcomes. Finally, an autophagy assay followed by western blotting was performed to study the effects of co-knockdown genes on cell autophagy in the presence and absence of cisplatin. The present data indicated the enhancement of cisplatin sensitivity in MCF-7 cells co-knocked down in BiP and 14-3-3ζ compared with either gene knockdown. Upregulation of JNK and cleaved-PARP1 protein levels as well as caspase-3 and JNK overactivation confirmed the results. A marked attenuation of autophagy and Beclin1 as well as ATG5 downregulation were detected in co-knockdown cells compared to knockdown with either BiP or 14-3-3ζ. Cisplatin sensitization of MCF-7 cells through double-knockdown of BiP and 14-3-3ζ highlights the potential of targeting UPR and autophagy factors to increase the effect of chemotherapy.
Project description:BackgroundIn CheckMate 227 Part 1, first-line nivolumab plus ipilimumab prolonged overall survival (OS) in patients with metastatic non-small-cell lung cancer (NSCLC) and tumor programmed death-ligand 1 (PD-L1) expression ≥1% versus chemotherapy. We report results from CheckMate 227 Part 2, which evaluated nivolumab plus chemotherapy versus chemotherapy in patients with metastatic NSCLC regardless of tumor PD-L1 expression.Patients and methodsSeven hundred and fifty-five patients with systemic therapy-naive, stage IV/recurrent NSCLC without EGFR mutations or ALK alterations were randomized 1 : 1 to nivolumab 360 mg every 3 weeks plus chemotherapy or chemotherapy. Primary endpoint was OS with nivolumab plus chemotherapy versus chemotherapy in patients with nonsquamous NSCLC. OS in all randomized patients was a hierarchically tested secondary endpoint.ResultsAt 19.5 months' minimum follow-up, no significant improvement in OS was seen with nivolumab plus chemotherapy versus chemotherapy in patients with nonsquamous NSCLC [median OS 18.8 versus 15.6 months, hazard ratio (HR) 0.86, 95.62% confidence interval (CI) 0.69-1.08, P = 0.1859]. Descriptive analyses showed OS improvement with nivolumab plus chemotherapy versus chemotherapy in all randomized patients (median OS 18.3 versus 14.7 months, HR 0.81, 95.62% CI 0.67-0.97) and in an exploratory analysis in squamous NSCLC (median OS 18.3 versus 12.0 months, HR 0.69, 95% CI 0.50-0.97). A trend toward improved OS was seen with nivolumab plus chemotherapy versus chemotherapy, regardless of the tumor mutation status of STK11 or TP53, regardless of tumor mutational burden, and in patients with intermediate/poor Lung Immune Prognostic Index scores. Safety with nivolumab plus chemotherapy was consistent with previous reports of first-line settings.ConclusionsCheckMate 227 Part 2 did not meet the primary endpoint of OS with nivolumab plus chemotherapy versus chemotherapy in patients with metastatic nonsquamous NSCLC. Descriptive analyses showed prolonged OS with nivolumab plus chemotherapy in all-randomized and squamous NSCLC populations, suggesting that this combination may benefit patients with untreated metastatic NSCLC.
Project description:Human breast cancer cell line MDA-MB-231 was transduced with lentivirus vector expressing non-specific control (NS) and CFH knockdown (shCFH1) sequences.
Project description:Analysis of MCF-7 cell clones lacking the E3 ubiquitin liganse CHIP. We used microarrays to detail the global gene expression profiles effected by CHIP in human brest cancer.