Project description:Stress-induced phosphoprotein 1 (STIP1), a co-chaperone that organizes other chaperones- heat shock proteins (HSP), was recently shown to be secreted by human ovarian cancer cells to induce cell proliferation. In neuronal tissues, binding to prion protein was required for STIP1 to activate the ERK (extracellular regulated MAP kinase) signaling pathways. However, in this study, we found that STIP1 stimulated cell proliferation of ovarian cancer via a bone morphogenetic protein (BMP) signaling pathway, not through the prion-ERK pathway. The STIP1 binding to a BMP receptor, ALK2 (activin A receptor, type II-like kinase 2), was necessary and sufficient to stimulate cancer cell proliferation. The binding of STIP1 to ALK2 activated the SMAD signaling pathway, leading to transcriptional activation of ID3 (inhibitor of DNA binding 3) that promotes cell proliferation. In conclusion, ovarian cancer tissues secrete STIP1 into the local environment and eventually into blood circulation of patients. In an autocrine and/or paracrine fashion, secreted STIP1 stimulates cancer cell proliferation by binding to ALK2 and activating the SMAD-ID3 signaling pathways. Elucidation of the mechanism by which STIP1 stimulates cancer cell proliferation may pave the way for developing novel therapeutic strategies for treatment of ovarian cancer. SKOV3 cell,treated without rhSTIP1 SKOV3 cell,treated with rhSTIP1 SKOV3 cell,treated without rhSTIP1-2 SKOV3 cell,treated with rhSTIP1-2
Project description:Stress-induced phosphoprotein 1 (STIP1), a co-chaperone that organizes other chaperones- heat shock proteins (HSP), was recently shown to be secreted by human ovarian cancer cells to induce cell proliferation. In neuronal tissues, binding to prion protein was required for STIP1 to activate the ERK (extracellular regulated MAP kinase) signaling pathways. However, in this study, we found that STIP1 stimulated cell proliferation of ovarian cancer via a bone morphogenetic protein (BMP) signaling pathway, not through the prion-ERK pathway. The STIP1 binding to a BMP receptor, ALK2 (activin A receptor, type II-like kinase 2), was necessary and sufficient to stimulate cancer cell proliferation. The binding of STIP1 to ALK2 activated the SMAD signaling pathway, leading to transcriptional activation of ID3 (inhibitor of DNA binding 3) that promotes cell proliferation. In conclusion, ovarian cancer tissues secrete STIP1 into the local environment and eventually into blood circulation of patients. In an autocrine and/or paracrine fashion, secreted STIP1 stimulates cancer cell proliferation by binding to ALK2 and activating the SMAD-ID3 signaling pathways. Elucidation of the mechanism by which STIP1 stimulates cancer cell proliferation may pave the way for developing novel therapeutic strategies for treatment of ovarian cancer.
Project description:Stress-induced phosphoprotein 1 (STIP1) is a co-chaperone that regulates other chaperone proteins that was recently shown to be secreted by ovarian cancer cells to induce cell proliferation. In this study, we found that STIP1 induced the phosphorylation of endogenous SMAD1/5, and knockdown of SMAD1/4/5 blocked STIP1-activated ID3 expression. Inhibition of ALK2, a serine/threonine kinase receptor, with siRNA or the specific inhibitor LDN193189, blocked STIP1-induced phosphorylation of SMAD1/5 and inhibited STIP1-related cell proliferation. The signaling pathway was found to involve binding of secreted STIP1 to ALK2, phosphorylation of SMAD, and activation of ID3 to induce cell proliferation was identified not only by in vitro immunofluorescent microscopy and biochemical identification of complex formation, but also by in vivo immunohistochemical analyses of ovarian cancer tissues. MDAH2774 cell treated with rhSTIP1 MDAH2774 cell treated without rhSTIP1 MDAH2774 cell treated with rhSTIP1-2 MDAH2774 cell treated without rhSTIP1-2
Project description:Stress-induced phosphoprotein 1 (STIP1) is a co-chaperone that regulates other chaperone proteins that was recently shown to be secreted by ovarian cancer cells to induce cell proliferation. In this study, we found that STIP1 induced the phosphorylation of endogenous SMAD1/5, and knockdown of SMAD1/4/5 blocked STIP1-activated ID3 expression. Inhibition of ALK2, a serine/threonine kinase receptor, with siRNA or the specific inhibitor LDN193189, blocked STIP1-induced phosphorylation of SMAD1/5 and inhibited STIP1-related cell proliferation. The signaling pathway was found to involve binding of secreted STIP1 to ALK2, phosphorylation of SMAD, and activation of ID3 to induce cell proliferation was identified not only by in vitro immunofluorescent microscopy and biochemical identification of complex formation, but also by in vivo immunohistochemical analyses of ovarian cancer tissues.
Project description:Ovarian cancer can metastasize to the omentum, which is associated with a complex tumor microenvironment. Omental stromal cells facilitate ovarian cancer colonization by secreting cytokines and growth factors. Improved understanding of the tumor supportive functions of specific cell populations in the omentum could identify strategies to prevent and treat ovarian cancer metastasis. Here, we showed that omental preadipocytes enhance the tumor initiation capacity of ovarian cancer cells. Secreted factors from preadipocytes supported cancer cell viability during nutrient and isolation stress and enabled prolonged proliferation. Co-culturing with pre-adipocytes led to upregulation of genes involved in extracellular matrix (ECM) organization, cellular response to stress, and regulation of insulin-like growth factor (IGF) signaling in ovarian cancer cells. IGF-1 induced ECM genes and increased alternative NF-κB signaling by activating RelB. Inhibiting the IGF-1 receptor (IGF1R) initially increased tumor omental adhesion but decreased growth of established preadipocyte-induced subcutaneous tumors as well as established intraperitoneal tumors. Together, this study shows that omental preadipocytes support ovarian cancer progression, which has implications for targeting metastasis.
Project description:Tissue inhibitor of metalloproteinase 1 (TIMP-1) controls matrix metalloproteinase (MMP) activity through 1:1 stochiometric binding. Human TIMP-1 fused to a glycosylphosphatidylinositol (GPI) anchor (TIMP-1-GPI) shifts the activity of TIMP-1 from the extracellular matrix to the cell surface. TIMP-1-GPI treated renal cell carcinoma cells (RCC) show increased apoptosis and reduced proliferation. Transcriptomic profiling and regulatory pathway mapping were used to identify potential mechanisms driving these effects. Significant changes in inhibitor of DNA binding (IDs), TGF-β1/SMAD and BMP pathways resulted from TIMP-1-GPI treatment. These events were linked to reduced TGF-β1 signaling mediated by inhibition of proteolytic processing of latent TGF-β1 by TIMP-1-GPI. Activity of TIMP-1 from the extracellular matrix to the cell surface. TIMP-1-GPI treated renal cell carcinoma cells (RCC) show increased apoptosis and reduced proliferation. Transcriptomic profiling and regulatory pathway mapping were used to identify potential mechanisms driving these effects. Significant changes in inhibitor of DNA binding (IDs), TGF-β1/SMAD and BMP pathways resulted from TIMP-1-GPI treatment. These events were linked to reduced TGF-β1 signaling mediated by inhibition of proteolytic processing of latent TGF-β1 by TIMP-1-GPI. Renal cell carcinoma cells were transfected with empty vector, rhTimp1 and 2 concentrations of Timp1-GPI fusion protein
Project description:Ovarian cancer is one of the most common female cancers. In the quest of effective anti-cancer agents, this study explores the effects of wogonin, a naturally occurring flavonoid, on the viability and migration of A2780 and Kuramochi ovarian cancer cell lines. Our findings demonstrate that wogonin not only impedes cancer cell growth and mobility in both in vitro and in vivo but also significantly enhances the cytotoxic efficacy of cisplatin. Mechanistic investigations reveal that wogonin suppresses genes associated with proliferation and EMT and upregulates metabolic pathways, particularly the AMPK signaling, which is crucial for increasing 5hmC levels, highlighting wogonin's role in promoting DNA demethylation through the stabilization of TET2. Our findings not only highlights the therapeutic potential of wogonin but also its preventative capability against ovarian cancer in individuals with metabolic disorders, such as diabetes, who are at increased risk for ovarian cancer. This study highlights wogonin's dual functionality in ovarian cancer treatment and prevention, emphasizing its promising prospects for future oncological applications.
Project description:The purpose of this study was to characterise the effects of trastuzumab and pertuzumab, either as single agents or as combination therapy on gene and protein expression in human ovarian cancer in vivo. Illumina BeadChips were used to profile the transcriptome after four days treatment of SKOV3 tumor xenografts. Although genes involved with HER2, MAP-kinase and p53 signaling pathways were commonly induced by all treatments, a greater number and variety of genes were differentially expressed by the complementary combination therapies compared to either drug on its own. The protein level of the CDK-inhibitors p21 and p27 were increased in response to both agents alone and further by the combination; pERK signaling was inhibited by all treatments; but only pertuzumab alone inhibited pAkt signaling. The expression of proliferation, apoptosis, cell division and cell cycle markers was distinct in a panel of primary ovarian cancer xenografts, suggesting heterogeneity of response in ovarian cancer and the need to establish biomarkers of response. This first comprehensive study of the molecular response to trastuzumab, pertuzumab and combination therapy in vivo highlights that there are both common and distinct downstream effects to different HER2 antibodies and that pathways may be invoked more strongly or in a different manner by a combination of agents. Some of the in vivo results for ovarian tumors differ from previous in vitro studies in breast cancer cells, emphasizing that the molecular response to anti-cancer agents involves variable and complex disease-specific interactions of signaling mechanisms. SCOV3 Ovarian cell line xenografts treated with Trastuzumab, pertuzumab or combination after 4 days
Project description:Deregulation of the transforming growth factor-? (TGF?) signaling pathway in epithelial ovarian cancer has been reported, but the precise mechanism underlying disrupted TGF? signaling in the disease remains unclear. We performed chromatin immunoprecipitation followed by sequencing (ChIP-seq) to investigate genome-wide screening of TGF?-induced SMAD4 binding in epithelial ovarian cancer. Following TGF? stimulation of the A2780 epithelial ovarian cancer cell line, we identified 2,362 SMAD4 binding loci and 318 differentially expressed SMAD4 target genes. Comprehensive examination of SMAD4-bound loci, revealed four distinct binding patterns: 1) Basal; 2) Shift; 3) Stimulated Only; 4) Unstimulated Only. SMAD4-bound loci were primarily classified as either Stimulated only (74%) or Shift (25%), indicating that TGF?-stimulation alters SMAD4 binding patterns in epithelial ovarian cancer cells compared to normal epithelial cells. Furthermore, based on gene regulatory network analysis, we determined that the TGF?-induced SMAD4-dependent regulatory network was strikingly different in ovarian cancer compared to normal cells. Importantly, the TGF?/SMAD4 target genes identified in the A2780 epithelial ovarian cancer cell line were predictive of patient survival, based on in silico mining of publically available patient data bases. In conclusion, our data highlight the utility of next generation sequencing technology to identify genome-wide SMAD4 target genes in epithelial ovarian cancer. The results link aberrant TGF?/SMAD signaling to ovarian tumorigenesis. Furthermore, the identified SMAD4 binding loci, combined with gene expression profiling and in silico data mining of patient cohorts, may provide a powerful approach to determine potential gene signatures with biological and future translational research in ovarian and other cancers. ChIP-Seq: 1 control lane. 4 unstimulated lanes 4 stimulated lanes Gene expression: 3 technical replicates each of SMAD4 stimulated and SMAD4 unstimulated cells