Jagged-2 (JAG2) enhances tumorigenicity and chemoresistance of colorectal cancer cells

Abstract

Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality. Recent studies have stated that NOTCH signaling plays an important role in the development and progression of CRC. However, the role of Jagged-2 (JAG2), one of the NOTCH ligands, has not been delineated in colorectal tumorigenesis and drug resistance. In the present study, we have examined the impact of targeting JAG2 on CRC cells. Among all the members of NOTCH ligands, only the expression of JAG2 was found up-regulated in the intestinal tumors of ApcMin/+ mice as compared to the nearby normal mucosa. JAG2 expression was also observed in a panel of human CRC cell lines. Pharmacological inhibition or genetic knockdown of β-catenin in CRC cell lines suppressed JAG2 expression, suggesting Wnt/β-catenin regulation of JAG2 expression. In addition, deletion of Apc gene in the intestinal cells of Apc conditional knockout mice resulted in up-regulation of JAG2 expression. Modulation of JAG2 expression significantly affected in vivo tumorigenicity of CRC cell lines. Moreover, knockdown of JAG2 sensitized CRC cells to chemotherapeutic agents, while ectopic expression of JAG2 increased chemoresistance of the CRC cells. Significant down-regulation of p21 was observed in JAG2-knockdown cells. Forced expression of p21 rescued the sensitivity of JAG2-knockdown cells to doxorubicin. In addition, the chemosensitivity of p21-null cells was not affected by JAG2 knockdown. These results suggest that JAG2 modulates the sensitivity of CRC cells to chemotherapeutic agents through p21. Our study identifies JAG2 as a novel target for therapeutic intervention of CRC.

ADAM17 is required for EGF-R–induced intestinal tumors via IL-6 trans-signaling

“…7 B , demonstrating a distinct gene expression signature in both mouse strains. The cluster of transcripts up-regulated in the Apc Min/+ tumors contained several transcripts that have been previously related to CRC (e.g., T [brachyury], IL11, GATA4, JAG2; Hellebrekers et al, 2009 ; Kilic et al, 2011 ; Calon et al, 2012 ; Vaish et al, 2017 ). A STRING-based network analysis of the top 500 regulated transcripts confirmed this observation and showed densely connected subnetworks up-regulated in the Apc Min/+ versus Apc Min/+ ::ADAM17 ex/ex tumors around Wnt signaling and cytokine/chemokine signaling (not depicted).…”

Notch signaling pathway mediates Doxorubicin-driven apoptosis in cancers

“… 7 Given the important function of Notch signaling pathway in cancers, the Notch pathway is a promising therapeutic target for cancer treatment. 8 – 12 As an example, the Notch inhibitors such as DAPT or Compound E have been widely used to treat cancers with Notch gain-of-function mutations, 7 while for cancers mediated by Notch loss-of-function mutations, activation of Notch signaling pathway is a promising therapeutic strategy. 8 – 12 …”

Development of a 15-gene signature for predicting prognosis in advanced colorectal cancer

“…PMM2 expression is significantly correlated with poor prognosis in renal cell carcinoma [27]. JAG2 promotes the motility and invasion of CRC cells [28,29]. RPN2 regulates cell proliferation of CRC cells [30].…”