BACKGROUND Epithelial 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. METHODS Immunohistochemistry 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. RESULTS Expression 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. CONCLUSIONS Taken 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.

中文翻译：

---

在体内和体外，ROR2通过激活IRE1α/ JNK / CHOP途径诱导高级浆液性卵巢癌的细胞凋亡。

背景技术上皮性卵巢癌（EOC）是女性生殖器肿瘤中最致命的癌症。考虑到当前的治疗状况，迫切需要确定新的疾病标志物和新颖的治疗策略。受体酪氨酸激酶家族在胚胎发育和疾病进展中起关键作用。但是，ROR2的矛盾研究结论使它在肿瘤中的作用混淆了，其潜在机制尚不清楚。在这项研究中，我们试图阐明ROR2对高级别浆液性卵巢癌（HGSOC）细胞的作用并揭示其机制。方法采用免疫组织化学法和蛋白质印迹法检测蛋白质表达。ROR2过表达腺病毒和慢病毒分别用于在体外和体内创建ROR2过表达模型。MTT分析，用集落形成法和transwell法测定癌细胞的增殖，侵袭和迁移能力。流式细胞仪检测细胞凋亡率。使用全转录组分析来探讨ROR2过表达组和阴性对照组之间差异表达的基因。使用靶向siRNA的IRE1α来敲低IRE1α。Kira6用于抑制IRE1α的磷酸化。结果与正常输卵管上皮或卵巢表面上皮组织相比，HGSOC组织中ROR2的表达显着降低。在HGSOC队列中，晚期或淋巴结阳性的患者倾向于表达较低的ROR2。ROR2的过表达可以抑制HGSOC细胞的增殖并诱导细胞凋亡。RNA测序分析表明ROR2的过表达可以诱导蛋白质反应的进行。BIP和磷酸化的IRE1α的上调也证实了该结果。此外，促死因子如CHOP，磷酸化的JNK和磷酸化的c-Jun也被上调。IRE1α基因敲低或Kira6处理可逆转ROR2过表达诱导的细胞凋亡。最后，肿瘤异种移植实验表明ROR2过表达可以显着抑制移植瘤的生长速度和体积。结论综上所述，ROR2的下调与HGSOC的发生和发展有关。ROR2的过表达可能抑制HGSOC细胞的细胞增殖并诱导细胞凋亡。其潜在机制可能是ROR2诱导的IRE1α/ JNK / CHOP途径的激活。BIP和磷酸化的IRE1α的上调也证实了该结果。此外，促死因子如CHOP，磷酸化的JNK和磷酸化的c-Jun也被上调。IRE1α基因敲低或Kira6处理可逆转ROR2过表达诱导的细胞凋亡。最后，肿瘤异种移植实验表明ROR2过表达可以显着抑制移植瘤的生长速度和体积。结论综上所述，ROR2的下调与HGSOC的发生和发展有关。ROR2的过表达可能抑制HGSOC细胞的细胞增殖并诱导细胞凋亡。其潜在机制可能是ROR2诱导的IRE1α/ JNK / CHOP途径的激活。BIP和磷酸化的IRE1α的上调也证实了该结果。此外，促死因子如CHOP，磷酸化的JNK和磷酸化的c-Jun也被上调。IRE1α基因敲低或Kira6处理可逆转ROR2过表达诱导的细胞凋亡。最后，肿瘤异种移植实验表明ROR2过表达可以显着抑制移植瘤的生长速度和体积。结论综上所述，ROR2的下调与HGSOC的发生和发展有关。ROR2的过表达可能抑制HGSOC细胞的细胞增殖并诱导细胞凋亡。其潜在机制可能是ROR2诱导的IRE1α/ JNK / CHOP途径的激活。磷酸化的JNK和磷酸化的c-Jun也被上调。IRE1α基因敲低或Kira6处理可逆转ROR2过表达诱导的细胞凋亡。最后，肿瘤异种移植实验表明ROR2过表达可以显着抑制移植瘤的生长速度和体积。结论综上所述，ROR2的下调与HGSOC的发生和发展有关。ROR2的过表达可能抑制HGSOC细胞的细胞增殖并诱导细胞凋亡。其潜在机制可能是ROR2诱导的IRE1α/ JNK / CHOP途径的激活。磷酸化的JNK和磷酸化的c-Jun也被上调。IRE1α基因敲低或Kira6处理可逆转ROR2过表达诱导的细胞凋亡。最后，肿瘤异种移植实验表明ROR2过表达可以显着抑制移植瘤的生长速度和体积。结论综上所述，ROR2的下调与HGSOC的发生和发展有关。ROR2的过表达可能抑制HGSOC细胞的细胞增殖并诱导细胞凋亡。其潜在机制可能是ROR2诱导的IRE1α/ JNK / CHOP途径的激活。肿瘤异种移植实验表明，ROR2过表达可以显着抑制移植瘤的生长速度和体积。结论综上所述，ROR2的下调与HGSOC的发生和发展有关。ROR2的过表达可能抑制HGSOC细胞的细胞增殖并诱导细胞凋亡。其潜在机制可能是ROR2诱导的IRE1α/ JNK / CHOP途径的激活。肿瘤异种移植实验表明，ROR2过表达可以显着抑制移植瘤的生长速度和体积。结论综上所述，ROR2的下调与HGSOC的发生和发展有关。ROR2的过表达可能抑制HGSOC细胞的细胞增殖并诱导细胞凋亡。其潜在机制可能是ROR2诱导的IRE1α/ JNK / CHOP途径的激活。