A novel c-Kit/phospho-prohibitin axis enhances ovarian cancer stemness and chemoresistance via Notch3—PBX1 and β-catenin—ABCG2 signaling

Abstract

Background: The underlying mechanism involved in ovarian cancer stemness and chemoresistance remains largely unknown. Here, we explored whether the regulation of c-Kit and plasma membrane prohibitin (PHB) affects ovarian cancer stemness and chemotherapy resistance.Methods: Mass spectrum analysis and an in vitro kinase assay were conducted to examine the phosphorylation of PHB at tyrosine 259 by c-Kit. The in vitro effects of c-Kit on membrane raft-PHB in ovarian cancer were determined using tissue microarray (TMA)-based immunofluorescence, western blotting, immunoprecipitation, colony and spheroid formation, cell migration and cell viability assays. In vivo tumor initiation and carboplatin treatment were conducted in nude mice.Results: We found that c-Kit and PHB colocalized in the raft domain and were positively correlated in human ovarian serous carcinoma. c-Kit interacted with PHB and facilitated the phosphorylation of PHB at tyrosine 259 (phospho-PHB Y259 ) in the membrane raft to enhance ovarian cancer cell motility. The generation of SKOV3GL-G4, a metastatic phenotype of SKOV3 green fluorescent protein and luciferase (GL) ovarian cancer cells, in xenograft murine ascites showed a correlation between metastatic potential and stem cell characteristics, as indicated by the expression of c-Kit, Notch3, Oct4, Nanog and SOX2. Further study revealed that after activation by c-Kit, raft-phospho-PHB Y259 interacted with Notch3 to stabilize Notch3 and increase the downstream target PBX1. Downregulation of raft-phospho-PHB Y259 increased the protein degradation of Notch3 through a lysosomal pathway and inhibited the β-catenin-ABCG2 signaling pathway. Moreover, raft-phospho-PHB Y259 played an important role in ovarian cancer stemness and tumorigenicity as well as resistance to platinum drug treatment in vitro and in vivo.Conclusions: These findings thus reveal a hitherto unreported interrelationship between c-Kit and PHB as well as the effects of raft-phospho-PHB Y259 on ovarian cancer stemness and tumorigenicity mediated by the Notch3 and β-catenin signaling pathways. Targeting the c-Kit/raft-phospho-PHB Y259 axis may provide a new therapeutic strategy for treating patients with ovarian cancer.

A20 regulates the therapeutic effect of anti-PD-1 immunotherapy in melanoma

“…It ought to be noted that previous studies have demonstrated that PHB mediated the resistance to chemotherapy and BRAF -targeted therapy in tumor. 46 47 More than this, our study implicated that PHB also mediated the resistance to immunotherapy by transducing the signal from A20 to STAT3, suggesting PHB as a versatile regulator and a promising therapeutic target for the determination of the treatment outcomes of diverse therapeutic approaches in cancer.…”

The Role of Notch3 Signaling in Cancer Stemness and Chemoresistance: Molecular Mechanisms and Targeting Strategies

“…In OC, the zinc transporter ZIP4 was identified as a novel CSC marker that physically interacts with Notch3 and activates Notch3 signaling (Fan et al, 2020). Several studies also found that the activation of Notch3 signaling enhances CSC activity, especially in chemoresistant OC tumors (Kim et al, 2017b;Jeong et al, 2017;Fang et al, 2020), and the relevant mechanisms are discussed in Platinum and Taxane. Yuan et al (2015) In HCC, the activation of Notch3 signaling was found to inhibit Wnt/β-catenin signaling and increase the expression of the stemness-related protein Nanog, which promotes the maintenance of the CSC population, thereby contributing to the pathogenesis of HCC (Zhang et al, 2015).…”

“…In OC, the zinc transporter ZIP4 was identified as a novel CSC marker that physically interacts with Notch3 and activates Notch3 signaling ( Fan et al, 2020 ). Several studies also found that the activation of Notch3 signaling enhances CSC activity, especially in chemoresistant OC tumors ( Kim et al, 2017b ; Jeong et al, 2017 ; Fang et al, 2020 ), and the relevant mechanisms are discussed in Platinum and Taxane .…”

“…Another main feature of Notch3 signaling is to induce tumor resistance against several kinds of chemotherapeutic drugs, including doxorubicin, platinum, taxane, epidermal growth factor receptor (EGFR)–tyrosine kinase inhibitors (TKIs) and gemcitabine (See in Notch3 and Drug Resistance ). Of note, Notch3-supported CSC activity is also involved in the mechanisms of tumor chemoresistance, as well as tumor metastasis and angiogenesis, indicating the key role of Notch3 signaling in cancer ( Sullivan et al, 2010 ; Xiao et al, 2011 ; McAuliffe et al, 2012 ; Cheung et al, 2016a ; Sansone et al, 2016 ; Kim et al, 2017a ; Kim et al, 2017b ; Jeong et al, 2017 ; Wang et al, 2018a ; Leontovich et al, 2018 ; Liu et al, 2018 ; Papadakos et al, 2019 ; Fan et al, 2020 ; Fang et al, 2020 ; Mansour et al, 2020 ).…”

Markers and Reporters to Reveal the Hierarchy in Heterogeneous Cancer Stem Cells

“…Acute myeloid leukemia (Abdollahpour-Alitappeh et al, 2018) Acute myeloid leukemia (Yabushita et al, 2018;Yan et al, 2019) -CD26 --Chronic myeloid leukemia (Herrmann et al, 2014) CD117/c-KIT Hepatocellular carcinoma (Xu et al, 2018) Ovarian cancer (Fang et al, 2020) Hepatocellular carcinoma (Xu et al, 2018)…”