Browsing by Author "Fan, Qipeng"

Now showing 1 - 8 of 8
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    Changes in mRNA/protein expression and signaling pathways in in vivo passaged mouse ovarian cancer cells
    (Public Library of Science, 2018-06-21) Cai, Qingchun; Fan, Qipeng; Buechlein, Aaron; Miller, David; Nephew, Kenneth P.; Liu, Sheng; Wan, Jun; Xu, Yan; Obstetrics and Gynecology, School of Medicine
    The cure rate for late stage epithelial ovarian cancer (EOC) has not significantly improved over several decades. New and more effective targets and treatment modalities are urgently needed. RNA-seq analyses of a syngeneic EOC cell pair, representing more and less aggressive tumor cells in vivo were conducted. Bioinformatics analyses of the RNA-seq data and biological signaling and function studies have identified new targets, such as ZIP4 in EOC. Many up-regulated tumor promoting signaling pathways have been identified which are mainly grouped into three cellular activities: 1) cell proliferation and apoptosis resistance; 2) cell skeleton and adhesion changes; and 3) carbohydrate metabolic reprograming. Unexpectedly, lipid metabolism has been the major down-regulated signaling pathway in the more aggressive EOC cells. In addition, we found that hypoxic responsive genes were at the center stage of regulation and detected functional changes were related to cancer stem cell-like activities. Moreover, our genetic, cellular, biochemical, and lipidomic analyses indicated that cells grown in 2D vs. 3D, or attached vs. suspended had dramatic changes. The important clinical implications of peritoneal cavity floating tumor cells are supported by the data proved in this work. Overall, the RNA-seq data provide a landscape of gene expression alterations during tumor progression.
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    Defective TGFβ signaling in bone marrow-derived cells prevents Hedgehog-induced skin tumors
    (American Association for Cancer Research, 2014-01-15) Fan, Qipeng; Gu, Dongsheng; Liu, Hailan; Yang, Ling; Zhang, Xiaoli; Yoder, Mervin C.; Kaplan, Mark H.; Xie, Jingwu; Department of Pediatrics, IU School of Medicine
    Hedgehog (Hh) signaling in cancer cells drives changes in the tumor microenvironment that are incompletely understood. Here we report that Hh- driven tumors exhibit an increase in myeloid-derived suppressor cells (MDSC) and a decrease in T cells, indicative of an immune suppressive tumor microenvironment. This change was associated with activated TGFβ signaling in several cell types in BCCs. We determined that TGFβ signaling in bone marrow (BM)-derived cells, not keratinocytes, regulates MDSC and promotes tumor development. Tgfbr2 deficiency in the BM-derived cells also reduced the size of previously developed tumors in mice. We identified CCL2 as the major chemokine attracting MDSC to tumor, whose expression was Tgfbr2-dependent, whereas its receptor CCR2 was highly expressed in MDSC population. CCL2 alone was sufficient to induce migration of MDSC. Moreover, the CCR2 inhibitors prevented MDSC migration towards skin cells in vitro, reduced MDSC accumulation and Hh signaling-driven tumor development in mice. Our results reveal a signaling network critical for Hh signaling in cancer cells to establish an effective immune suppressive microenvironment during tumor development.
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    FOXM1 is a downstream target of LPA and YAP oncogenic signaling pathways in high grade serous ovarian cancer
    (Oncotarget, 2015-09-29) Fan, Qipeng; Cai, Qingchun; Xu, Yan; Department of Obstetrics and Gynecology, IU School of Medicine
    Lysophosphatidic acid (LPA), a prototypical ligand for G protein coupled receptors, and Forkhead box protein M1 (FOXM1), a transcription factor that regulates expression of a wide array of genes involved in cancer initiation and progression, are two important oncogenic signaling molecules in human epithelial ovarian cancers (EOC). We conducted in vitro mechanistic studies using pharmacological inhibitors, genetic forms of the signaling molecules, and RNAi-mediated gene knock-down to uncover the molecular mechanisms of how these two molecules interact in EOC cells. Additionally, in vivo mouse studies were performed to confirm the functional involvement of FOXM1 in EOC tumor formation and progression. We show for the first time that LPA up-regulates expression of active FOXM1 splice variants in a time- and dose-dependent manner in the human EOC cell lines OVCA433, CAOV3, and OVCAR5. Gi-PI3K-AKT and G12/13-Rho-YAP signaling pathways were both involved in the LPA receptor (LPA1-3) mediated up-regulation of FOXM1 at the transcriptional level. In addition, down-regulation of FOXM1 in CAOV3 xenografts significantly reduced tumor and ascites formation, metastasis, and expression of FOXM1 target genes involved in cell proliferation, migration, or invasion. Collectively, our data link the oncolipid LPA, the oncogene YAP, and the central regulator of cell proliferation/mutagenesis FOXM1 in EOC cells. Moreover, these results provide further support for the importance of these pathways as potential therapeutic targets in EOC.
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    LPA induced FOXM1 up-regulation in ovarian cancer cells via both the PI3K and YAP pathways
    (Office of the Vice Chancellor for Research, 2015-04-17) Fan, Qipeng; Cai, Qingchun; Xu, Yan
    The cure rate for late stage epithelial ovarian cancer (EOC) has not significantly improved for patients over the past 20 years. The current standard of care is aggressive surgery followed by platinum/paclitaxel chemotherapy. However, approximately 25% of patients will develop platinum resistant cancer within 6 months and the overall 5-year survival is only 31%. Therefore, new and more effective treatment modalities that target additional molecular pathways are urgently needed. The functional and mechanistic studies presented here clearly support that the FOXM1 network is an important target for developing new EOC therapeutics. This network includes the newly identified LPA as an up-stream regulator of FOXM1 and down-stream targets. Tumor cell specific targeting may be necessary and tumor and/or tumor-host interactions generating secreted factors, such as amphiregulin (AREG) and/or VEGF, may be used as follow-up factors to monitor treatment and disease progression.
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    The novel ZIP4 regulation and its role in ovarian cancer
    (Impact Journals, 2017-09-30) Fan, Qipeng; Cai, Qingchun; Li, Pengfei; Wang, Wenyan; Wang, Jing; Gerry, Emily; Wang, Tian-Li; Shih, Ie-Ming; Nephew, Kenneth P.; Xu, Yan; Obstetrics and Gynecology, School of Medicine
    Our RNAseq analyses revealed that ZIP4 is a top gene up-regulated in more aggressive ovarian cancer cells. ZIP4's role in cancer stem cells has not been reported in any type of cancer. In addition, the role and regulation of ZIP4, a zinc transporter, have been studied in the context of extracellular zinc transporting. Factors other than zinc with ZIP4 regulatory effects are essentially unknown. ZIP4 expression and its regulation in epithelial ovarian cancer cells was assessed by immunoblotting, quantitative PCR, or immunohistochemistry staining in human ovarian tissues. Cancer stem cell-related activities were examined to evaluate the role of ZIP4 in human high-grade serous ovarian cancer cells in vitro and in vivo. RNAi and CRISPR techniques were used to knockdown or knockout ZIP4 and related genes. Ovarian cancer tissues overexpressed ZIP4 when compared with normal and benign tissues. ZIP4 knockout significantly reduced several cancer stem cell-related activities in EOC cells, including proliferation, anoikis-resistance, colony-formation, spheroid-formation, drug-resistance, and side-population in vitro. ZIP4-expressing side-population highly expressed known CSC markers ALDH1 and OCT4. ZIP4 knockout dramatically reduced tumorigenesis and ZIP4 overexpression increased tumorigenesis in vivo. In addition, the ZIP4-expressing side-population had the tumor initiating activity. Moreover, the oncolipid lysophosphatic acid effectively up-regulated ZIP4 expression via the nuclear receptor peroxisome proliferator-activated receptor gamma and lysophosphatic acid 's promoting effects in cancer stem cell-related activities in HGSOC cells was at least partially mediated by ZIP4 in an extracellular zinc-independent manner. Our critical data imply that ZIP4 is a new and important cancer stem cell regulator in ovarian cancer. Our data also provide an innovative interpretation for the apparent disconnection between low levels of zinc and up-regulation of ZIP4 in ovarian cancer tissues.
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    A Novel ZIP4-HDAC4-VEGFA Axis in High-Grade Serous Ovarian Cancer
    (MDPI, 2021-07-29) Fan, Qipeng; Li, Lihong; Wang, Tian-Li; Emerson, Robert E.; Xu, Yan; Obstetrics and Gynecology, School of Medicine
    We have recently identified ZIP4 as a novel cancer stem cell (CSC) marker in high-grade serous ovarian cancer (HGSOC). While it converts drug-resistance to cisplatin (CDDP), we unexpectedly found that ZIP4 induced sensitization of HGSOC cells to histone deacetylase inhibitors (HDACis). Mechanistically, ZIP4 selectively upregulated HDAC IIa HDACs, with little or no effect on HDACs in other classes. HDAC4 knockdown (KD) and LMK-235 inhibited spheroid formation in vitro and tumorigenesis in vivo, with hypoxia inducible factor-1 alpha (HIF1α) and endothelial growth factor A (VEGFA) as functional downstream mediators of HDAC4. Moreover, we found that ZIP4, HDAC4, and HIF1α were involved in regulating secreted VEGFA in HGSOC cells. Furthermore, we tested our hypothesis that co-targeting CSC via the ZIP4-HDAC4 axis and non-CSC using CDDP is necessary and highly effective by comparing the effects of ZIP4-knockout/KD, HDAC4-KD, and HDACis, in the presence or absence of CDDP on tumorigenesis in mouse models. Our results showed that the co-targeting strategy was highly effective. Finally, data from human HGSOC tissues showed that ZIP4 and HDAC4 were upregulated in a subset of recurrent tumors, justifying the clinical relevance of the study. In summary, our study provides a new mechanistic-based targeting strategy for HGSOC.
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    Simultaneous Inhibition of MEK and Hh Signaling Reduces Pancreatic Cancer Metastasis
    (MDPI, 2018-10-26) Gu, Dongsheng; Lin, Hai; Zhang, Xiaoli; Fan, Qipeng; Chen, Shaoxiong; Shahda, Safi; Liu, Yunlong; Sun, Jie; Xie, Jingwu; Pediatrics, School of Medicine
    Pancreatic cancer, mostly pancreatic ductal adenocarcinoma (PDAC), is one of the most lethal cancer types, with an estimated 44,330 death in 2018 in the US alone. While targeted therapies and immune checkpoint inhibitors have significantly improved treatment options for patients with lung cancer and renal cell carcinomas, little progress has been made in pancreatic cancer, with a dismal 5-year survival rate currently at ~8%. Upon diagnosis, the majority of pancreatic cancer cases (~80%) are already metastatic. Thus, identifying ways to reduce pancreatic cancer metastasis is an unmet medical need. Furthermore, pancreatic cancer is notorious resistant to chemotherapy. While Kirsten RAt Sarcoma virus oncogene (K-RAS) mutation is the major driver for pancreatic cancer, specific inhibition of RAS signaling has been very challenging, and combination therapy is thought to be promising. In this study, we report that combination of hedgehog (Hh) and Mitogen-activated Protein/Extracellular Signal-regulated Kinase Kinase (MEK) signaling inhibitors reduces pancreatic cancer metastasis in mouse models. In mouse models of pancreatic cancer metastasis using human pancreatic cancer cells, we found that Hh target gene Gli1 is up-regulated during pancreatic cancer metastasis. Specific inhibition of smoothened signaling significantly altered the gene expression profile of the tumor microenvironment but had no significant effects on cancer metastasis. By combining Hh signaling inhibitor BMS833923 with RAS downstream MEK signaling inhibitor AZD6244, we observed reduced number of metastatic nodules in several mouse models for pancreatic cancer metastasis. These two inhibitors also decreased cell proliferation significantly and reduced CD45⁺ cells (particularly Ly6G⁺CD11b⁺ cells). We demonstrated that depleting Ly6G⁺ CD11b⁺ cells is sufficient to reduce cancer cell proliferation and the number of metastatic nodules. In vitro, Ly6G⁺ CD11b⁺ cells can stimulate cancer cell proliferation, and this effect is sensitive to MEK and Hh inhibition. Our studies may help design novel therapeutic strategies to mitigate pancreatic cancer metastasis.
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    ZIP4 Is a Novel Cancer Stem Cell Marker in High-Grade Serous Ovarian Cancer
    (MDPI, 2020-12-09) Fan, Qipeng; Zhang, Wen; Emerson, Robert E.; Xu, Yan; Obstetrics and Gynecology, School of Medicine
    High-grade serous ovarian cancer (HGSOC) is one of the most deadly and heterogenic cancers. We have recently shown that ZIP4 (gene name SLC39A4), a zinc transporter, is functionally involved in cancer stem cell (CSC)-related cellular activities in HGSOC. Here, we identified ZIP4 as a novel CSC marker in HGSOC. Fluorescence-activated cell sorter (FACS)-sorted ZIP4+, but not ZIP4- cells, formed spheroids and displayed self-renewing and differentiation abilities. Over-expression of ZIP4 conferred drug resistance properties in vitro. ZIP4+, but not ZIP4- cells, formed tumors/ascites in vivo. We conducted limiting dilution experiments and showed that 100-200 ZIP4+ cells from both PE04 and PEA2 cells formed larger tumors than those from 100-200 ALDH+ cells in mice. Mechanistically, we found that ZIP4 was an upstream regulator of another CSC-marker, NOTCH3, in HGSOC cells. NOTCH3 was functionally involved in spheroid formation in vitro and tumorigenesis in vivo in HGSOC. Genetic compensation studies showed that NOTCH3, but not NOTCH1, was a critical downstream mediator of ZIP4. Furthermore, NOTCH3, but not NOTCH1, physically bound to ZIP4. Collectively, our data suggest that ZIP4 is a novel CSC marker and the new ZIP4-NOTCH3 axis represents important therapeutic targets in HGSOC.