ROR2 induces cell apoptosis via activating IRE1α/JNK/CHOP pathway in high-grade serous ovarian carcinoma in vitro and in vivo

Abstract

BackgroundEpithelial ovarian cancer (EOC) is the most lethal cancer in female genital tumors. New disease markers and novel therapeutic strategies are urgent to identify considering the current status of treatment. Receptor tyrosine kinases family plays critical roles in embryo development and disease progression. However, ambivalent research conclusions of ROR2 make its role in tumor confused and the underlying mechanism is far from being understood. In this study, we sought to clarify the effects of ROR2 on high-grade serous ovarian carcinoma (HGSOC) cells and reveal the mechanism.MethodsImmunohistochemistry assay and western-blot assay were used to detect proteins expression. ROR2 overexpression adenovirus and Lentivirus were used to create ROR2 overexpression model in vitro and in vivo, respectively. MTT assay, colony formation assay and transwell assay were used to measure the proliferation, invasion and migration ability of cancer cells. Flow cytometry assay was used to detect cell apoptosis rate. Whole transcriptome analysis was used to explore the differentially expressed genes between ROR2 overexpression group and negative control group. SiRNA targeted IRE1α was used to knockdown IRE1α. Kira6 was used to inhibit phosphorylation of IRE1α.ResultsExpression of ROR2 was significantly lower in HGSOC tissues compared to normal fallopian tube epithelium or ovarian surface epithelium tissues. In HGSOC cohort, patients with advanced stages or positive lymph nodes were prone to express lower ROR2. Overexpression of ROR2 could repress the proliferation of HGSOC cells and induce cell apoptosis. RNA sequencing analysis indicated that ROR2 overexpression could induce unfold protein response. The results were also confirmed by upregulation of BIP and phosphorylated IRE1α. Furthermore, pro-death factors like CHOP, phosphorylated JNK and phosphorylated c-Jun were also upregulated. IRE1α knockdown or Kira6 treatment could reverse the apoptosis induced by ROR2 overexpression. Finally, tumor xenograft experiment showed ROR2 overexpression could significantly repress the growth rate and volume of transplanted tumors.ConclusionsTaken together, ROR2 downregulation was associated with HGSOC development and progression. ROR2 overexpression could repress cell proliferation and induce cell apoptosis in HGSOC cells. And the underlying mechanism might be the activation of IRE1α/JNK/CHOP pathway induced by ROR2.

FASN inhibition as a potential treatment for endocrine-resistant breast cancer

“…Classically, both ROR1 and ROR2, are involved in neurogenesis and embryonic development. Moreover, expression of ROR1 and ROR2 is associated with increased invasion and poor prognosis in numerous cancers [35,36]. Interestingly, in certain cancers, ROR2 expression exhibits tumor-suppressing characteristics.…”

“…Not only does ROR2 possess tumor-suppressing traits but is also implicated in inducing apoptosis through the EnRS pathway. Recently, ROR2 promoted apoptosis in ovarian carcinoma through the induction EnRS sensing protein, inositol requiring enzyme-1α (IRE1α) and downstream C/EBP homologous protein (CHOP) [35,36]. Thus, ROR2 overexpression observed in response to TVB and tamoxifen treatment could be illustrating tumor-suppressing characteristics.…”

“…Intriguingly, the increased expression of ROR2 recorded in the phospho-RTK assay could be a potential mediator of endoplasmic reticulum stress. Previous studies connecting ROR2 expression to CHOP induced apoptosis highlight a potential connection to the PERK/p-eIF2α EnRS pathway [36]. Not only does p-eIF2α lead to a decrease in protein translation, but also allows the initiation complex to continue down the mRNA until it reaches the alternate reading frame [31].…”

ROR2 has a protective role in melanoma by inhibiting Akt activity, cell-cycle progression, and proliferation

“…The mechanisms described implicate the activation of the Rho-family of small GTPases [ 39 ] or the upregulation of c-myc, Cyclin D1, Cyclin E, and CDK4 [ 40 ], and PCNA and CDK1 [ 12 ]. In contrast, other studies showed that ROR2 inhibited proliferation in gastric [ 26 ], colorectal [ 23 ], and ovarian cancer [ 41 ], as well as in esophageal squamous cell carcinoma [ 42 ]. However, these studies relied only on ectopic expression of ROR2 [ 26 , 41 , 42 ] or provided inconsistent results between overexpressing and silencing experiments [ 23 ].…”

Temporal Quantitative Proteomics Analysis of Neuroblastoma Cells Treated with Bovine Milk-Derived Extracellular Vesicles Highlights the Anti-Proliferative Properties of Milk-Derived Extracellular Vesicles

“…Proliferation regulators MKI67 (Figure 6C) and MAP2K4 (Figure 6D) were altered upon MEV treatment [44,55]. Apoptosis regulator ROR2 [56] was significantly upregulated in 72 h MEVs treated cells compared to untreated (Figure 6E). ROR2 is also known to participate in negative regulation of Wnt signalling activity.…”