Nuclear orphan receptor NR4A2 confers chemoresistance and predicts unfavorable prognosis of colorectal carcinoma patients who received postoperative chemotherapy

BackgroundNR4A2, an orphan nuclear receptor essential in neuron generation, has been recently linked to inflammatory and metabolic pathways of colorectal carcinoma (CRC). However, the effects of NR4A2 on chemo-resistance and postoperative prognosis of CRC remain unknown.MethodsNR4A2 was transfected into CRC cells to investigate its effects on chemo-resistance to 5-fluorouracil and oxaliplatin and chemotherapeutics-induced apoptosis. We also investigated prostaglandin E2 (PGE₂)-induced NR4A2 expression and its effect on chemo-resistance. Tissue microarrays including 51 adenoma, 14 familial adenomatous polyposis with CRC, 17 stage IV CRC with adjacent mucosa and 682 stage I–III CRC specimens were examined immunohistochemically for NR4A2 expression. Median follow-up time for stage I–III CRC patients was 53 months.ResultsEctopic expression of NR4A2 increased the chemo-resistance, and attenuated the chemotherapeutics-induced apoptosis. Transient treatment of PGE₂ significantly up-regulated NR4A2 expression via protein kinase A pathway and increased the chemo-resistance. NR4A2 expression in epithelials consecutively increased from adenoma, adjacent mucosa to CRC (P_trend < 0.001). In multivariate Cox regression analyses, high NR4A2 expression in cancer nuclei (immunoreactive score ? 4) significantly predicted a shorter disease-specific survival (DSS) of CRC patients (hazard ratio [HR] = 1.88, P = 0.024). High NR4A2 expression specifically predicted a shorter DSS of colon cancer patients (dichotomisation, HR = 2.55, log-rank test P = 0.011), especially for those who received postoperative 5-fluorouracil/leucovorin plus oxaliplatin (FOLFOX) chemotherapy (3-score range, HR = 1.86, log-rank test P = 0.020).ConclusionHigh expression of NR4A2 in CRC cells confers chemo-resistance, attenuates chemotherapeutics-induced apoptosis, and predicts unfavorable prognosis of colon cancer patients, especially for those who received postoperative chemotherapy. NR4A2 may be prognostic and predictive for colon cancer.     

High Cytoplasmic Expression of the Orphan Nuclear Receptor NR4A2 Predicts Poor Survival in Nasopharyngeal Carcinoma

Objective: This study aimed at investigating whether the orphan nuclear receptor NR4A2 is significantlyassociated with clinicopathologic features and overall survival of patients with nasopharyngeal carcinoma (NPC).Methods: Immunohistochemistry was performed to determine NR4A2 protein expression in 84 NPC tissues and20 non-cancerous nasopharyngeal (NP) tissues. The prognostic significance of NR4A2 protein expression wasevaluated using Cox proportional hazards regression models and Kaplan-Meier survival analysis. Results: Wedid not find a significant association between total NR4A2 expression and clinicopathological variables in 84patients with NPC. However, we observed that high cytoplasmic expression of NR4A2 was significantly associatedwith tumor size (T classification) (P = 0.006), lymph node metastasis (N classification) (P = 0.002) and clinicalstage (P = 0.017). Patients with higher cytoplasmic NR4A2 expression had a significantly lower survival ratethan those with lower cytoplasmic NR4A2 expression (P = 0.004). Multivariate Cox regression analysis analysissuggested that the level of cytoplasmic NR4A2 expression was an independent prognostic indicator for overallsurvival of patients with NPC (P = 0.033). Conclusions: High cytoplasmic expression of NR4A2 is a potentialunfavorable prognostic factor for patients with NPC.     

Nuclear receptor 4A2 (NR4A2) is a druggable target for glioblastomas

Journal of Neuro-Oncology - The orphan nuclear receptor 4A2 (NR4A2) has been extensively characterized in subcellular regions of the brain and is necessary for the function of dopaminergic neurons....     

转录因子NR4A2在卵巢上皮性肿瘤组织中的表达及其临床意义

目的:探讨转录因子NR4A2在卵巢上皮性肿瘤组织中的表达及其临床意义。方法:采用免疫组化SP法检测39例卵巢上皮性癌、28例交界性卵巢上皮性肿瘤、27例良性卵巢上皮性肿瘤及17例正常卵巢组织中NR4A2蛋白的表达,分析其与临床病例参数的关系。结果:NR4A2蛋白在卵巢上皮性癌、交界性卵巢上皮性肿瘤、良性卵巢上皮性肿瘤及正常卵巢组织中的阳性表达率分别为53.8%(21/39)、25.0%(7/28)、7.4%（2/27）、5.9%（1/17）。NR4A2蛋白在卵巢上皮性癌组织中的阳性表达率明显高于交界性卵巢上皮性肿瘤组织、良性卵巢上皮性肿瘤组织和正常卵巢组织（P均<0.05）。交界性卵巢上皮性肿瘤的阳性表达率虽然高于良性卵巢上皮性肿瘤及正常卵巢,但差异无统计学意义（P＞0.05）。良性卵巢上皮性肿瘤的阳性表达率高于正常卵巢组,但两组之间的阳性表达率差异无统计学意义（P＞0.05）。在卵巢上皮性癌组织中,NR4A2蛋白的阳性表达率随手术分期的增加而增加（P＜0.05）,但与病理分级以及有无淋巴结转移和来源无关（P＞0.05）。结论:在卵巢上皮性癌中转录因子NR4A2呈现明显高表达,且其表达水平与手术分期相关,提示NR4A2可能与卵巢癌的发生发展相关。     

Nuclear orphan receptor NR2F6 confers cisplatin resistance in epithelial ovarian cancer cells by activating the Notch3 signaling pathway

The primary challenge facing treatment of epithelial ovarian cancer (EOC) is the high frequency of chemoresistance, which severely impairs the quality of life and survival of patients with EOC. Our study aims to investigate the mechanisms by which upregulation of NR2F6 induces chemoresistance in EOC. The biological roles of NR2F6 in EOC chemoresistance were explored in vitro by Sphere, MTT and AnnexinV/PI assay, and in vivo using an ovarian cancer orthotopic transplantation model. Bioinformatics analysis, luciferase assay, CHIP and IP assays were performed to identify the mechanisms by which NR2F6 promotes chemoresistance in EOC. The expression of NR2F6 was significantly upregulated in chemoresistant EOC tissue, and NR2F6 expression was correlated with poorer overall survival. Moreover, overexpression of NR2F6 promotes the EOC cancer stem cell phenotype; conversely, knockdown of NR2F6 represses the EOC cancer stem cell phenotype and sensitizes EOC to cisplatin in vitro and in vivo. Our results further demonstrate that NR2F6 sustains activated Notch3 signaling, resulting in chemoresistance in EOC cells. Notably, NR2F6 acts as an informative biomarker to identify the population of EOC patients who are likely to experience a favorable objective response to gamma-secretase inhibitors (GSI), which inhibit Notch signaling. Therefore, concurrent inhibition of NR2F6 and treatment with GSI and cisplatin-based chemotherapy may be a novel therapeutic approach for NR2F6-overexpressing EOC. In summary, we have, for the first time, identified an important role for NR2F6 in EOC cisplatin resistance. Our study suggests that GSI may serve as a potential targeted treatment for patients with NR2F6-overexpressing EOC.     

多柔比星诱导乳腺癌细胞PARP-1活性上调依赖于Kif4A蛋白低表达

背景与目的：化疗作为乳腺癌术后治疗的重要手段,由其引发的耐药现象备受关注,而耐药的出现与DNA损伤修复异常增强密切相关。驱动蛋白家族成员4A(kinesin family member 4A,Kif4A)和聚腺苷酸二磷酸核糖聚合酶-1[poly(ADP-ribose)polymerase,PARP-1]是重要的DNA损伤修复分子。本研究探讨Kif4A在多柔比星诱导乳腺癌细胞PARP-1活性上调中的作用及意义。方法：蛋白质印迹法检测多柔比星处理后乳腺癌MDA-MB-231和MCF-7细胞Kif4A蛋白表达及PARP-1活性的变化;并检测高表达Kif4A蛋白后,乳腺癌细胞PARP-1蛋白表达及其活性变化;流式细胞技术检测多柔比星联合PARP-1抑制剂3-氨基苯酰胺(3-Aminobenzamide,3-ABA)干预后乳腺癌细胞的凋亡情况。结果：多柔比星能上调PARP-1活性并诱导乳腺癌细胞Kif4A蛋白低表达,两者都呈浓度和时间依赖性;高表达Kif4A后,PARP-1活性被明显抑制,细胞凋亡数增加,而多柔比星能部分逆转由Kif4A高表达而引起的PARP-1活性抑制。多柔比星和3-ABA都诱导乳腺癌细胞凋亡,联合使用能增加细胞凋亡,与单独使用比较,差异有统计学意义(P<0.05)。结果还显示,多柔比星、PARP-1抑制剂3-ABA及高表达的Kif4A诱导的MDA-MB-231细胞凋亡数高于MCF-7细胞,差异有统计学意义(P<0.05)。结论：多柔比星诱导乳腺癌细胞PARP-1活性上调依赖于细胞Kif4A蛋白低表达,Kif4A有望成为逆转多柔比星耐药的新靶点。     

Liver receptor homolog-1 (LRH-1): a potential therapeutic target for cancer

Liver receptor homolog-1 (LRH-1) is a nuclear receptor involved in various biological processes. This nuclear receptor has critical functions in embryonic development as well as in adult homeostasis. Although the physiological functions of LRH-1 in normal breast, pancreas, and intestine have been widely investigated, the dysregulation that occurs during pathological conditions is not well understood. LRH-1 has been implicated in pancreatic, breast, and gastrointestinal cancer, where it exerts its effect of initiation and progression by promoting cell proliferation and metastasis. In addition to mechanistic studies, LRH-1 agonists and antagonists are being explored. Identification and development of endogenous and synthetic ligands has been pursued using computational-based structural analysis. Through ligand identification and a thorough understanding of the pathological roles of LRH-1, new therapeutic avenues for cancer treatment based upon LRH-1 may be a desirable focus for further research.     

长链非编码RNA NR2F2-AS1对胃癌细胞增殖、凋亡的影响

目的:研究lncRNA NR2F2-AS1对胃癌细胞增殖、凋亡的影响,并探讨其机制。方法:运用qRT-PCR法检测细胞中 NR2F2-AS1、miR-425-5p的mRNA表达情况;将pcDNA组（转染pcDNA）、pcDNA-NR2F2-AS1组（转染pcDNA-NR2F2-AS1）、sh-NR2F2-AS1组(转染sh-NR2F2-AS1)、sh-NC组(转染sh-NC)、anti-miR-NC组（转染anti-miR-NC）、anti-miR-425-5p组（转染anti-miR-425-5p）、pcDNA-NR2F2-AS1+miR-NC组（共转染pcDNA-NR2F2-AS1和miR-NC）、pcDNA-NR2F2-AS1+miR-425-5p组（共转染pcDNA-NR2F2-AS1和miR-425-5p mimics）转染至MGC-803、MKN-45细胞;MTT法检测细胞的增殖;流式细胞术检测细胞的凋亡;双荧光素酶报告基因检测实验检测细胞的荧光活性。结果:与正常胃黏膜上皮细胞GES-1相比,胃癌细胞MGC-803、MKN-45中NR2F2-AS1的表达显著降低,miR-425-5p的表达显著升高;过表达NR2F2-AS1、抑制miR-425-5p均可抑制胃癌细胞增殖,促进细胞凋亡;miR-425-5p可抑制野生型NR2F2-AS1的MGC-803、MKN-45细胞的荧光活性;过表达miR-425-5p可逆转过表达NR2F2-AS1对MGC-803、MKN-45细胞增殖和凋亡的作用。结论:lncRNA NR2F2-AS1可抑制胃癌细胞的增殖,促进细胞凋亡,其机制可能与靶向miR-425-5p有关,将可为胃癌的治疗提供新靶点。     

Adenosine A2A receptor activation reduces brain metastasis via SDF-1/CXCR4 axis and protecting blood-brain barrier

Brain metastasis is a leading cause of death worldwide, but the mechanism involved remains unclear. Stromal cell-derived factor-1 (SDF-1)/C-X-C motif chemokine receptor 4 (CXCR4) signaling has been reported to induce the directed metastasis of cancers, and adenosine A2A receptor activation suppresses the SDF-1/CXCR4 interaction. However, whether A2A receptor activation implicates the SDF-1/CXCR4 signaling pathway and thus modulates brain metastasis remains unclear. In this study, Western blot was performed to evaluate the protein levels. Cell invasion and migration assays were used to estimate the metastasis ability of PC-9 cells. The viability of cells was demonstrated by lactate dehydrogenase and cell proliferation assays. And the findings in vitro were further identified in nude mice. Notably, adenosine A2A receptor activation inhibited the proliferation and viability of PC-9 cells and thus suppressed the brain metastasis. A2A receptor stimulation protected the function of blood-brain barrier (BBB). The suppression of brain metastasis and the protection of BBB by A2A receptor relied on SDF-1/CXCR4 signaling, and treatment using A2A receptor agonist and CXCR4 antagonist protected the nude mice from malignancy metastasis in vivo. Adenosine A2A receptor activation suppressed the brain metastasis by implicating the SDF-1/CXCR4 axis and protecting the BBB.     

Cyclosporin A enhances the apoptotic effects of N-(4-hydroxyphenyl)retinamide in breast cancer cells

4HPR, an analogue of ATRA, effectively induces growth inhibition and apoptosis in breast cancer cell lines and animal models but is ineffective against advanced human breast tumors. Different compounds, including tamoxifen, are currently being tested to increase 4HPR efficacy in the clinic. Here, we report that cyclosporin A selectively increases the ability of 4HPR, but not ATRA, to induce growth inhibition and apoptosis in ER(+) and ER(-) breast cancer cell lines. Increased apoptosis by the 4HPR and cyclosporin A combination was correlated with increased production of the free radical nitric oxide. Thus, the 4HPR and cyclosporin A combination may potentially be a novel therapeutic modality against breast tumors.     

乙醛脱氢酶1A1过表达对胃癌细胞生物学行为的影响

目的 探讨乙醛脱氢酶1A1（ALDH1A1）过表达对胃癌细胞增殖、克隆形成和侵袭能力的影响。方法 成功构建过表达ALDH1A1的pEGFP-N1-ALDH1A1真核载体并转染至人胃癌细胞株MKN-28（实验组）,同时设空载体组（转染空载体pEGFP-N1的MKN-28细胞）和空白对照组（未行任何干预措施的MKN-28细胞）,分别于转染96 h后采用四甲基偶氮唑盐（MTT）法、克隆形成实验及Transwell小室侵袭实验检测ALDH1A1过表达对MKN-28细胞增殖、克隆形成和侵袭能力的影响。结果 实验组转染96 h后的增殖抑制率为（19.26±2.01）％,均低于空载体组和空白对照组,而克隆形成率和穿膜细胞数分别为（25.44±1.74）％和（219.78±12.93）个,均高于空载体组和对照组,差异有统计学意义（P＜0.05）。空白对照组和空载体组以上指标的差异均无统计学意义（P＞0.05）。结论 在MKN-28细胞中过表达ALDH1A1,可增强肿瘤细胞的增殖、克隆形成和侵袭能力,提示ALDH1A1可能参与了胃癌的发生、发展。     

NR4A3和Pan-TRK免疫组化染色在涎腺腺泡细胞癌与分泌性癌鉴别诊断中的应用

目的:探讨NR4A3、Pan-TRK免疫组化染色在涎腺腺泡细胞癌（acinic cell carcinoma,AciCC）、分泌性癌(secretory carcinoma of salivary gland,SCSG)鉴别诊断中的应用价值。方法:收集2010年03月至2021年01月我院病理科存档的22例AciCC、13例SCSG及132例其它涎腺肿瘤,分别进行NR4A3、Pan-TRK免疫组化染色并分析表达情况。结果:NR4A3免疫组化染色显示AciCC（21/22）阳性,其中17例局灶/弥漫强阳,4例中等阳性,1例阴性。13例SCSG及其它132例涎腺肿瘤均（-）。Pan-TRK免疫组化显示13例SCSG均（+）、22例AciCC均（-）。NR4A3在AciCC中敏感性为95.5%,特异性为100%。结论:NR4A3是AciCC一种新标记物,特别与SCSG的鉴别诊断中,联合使用Pan-TRK,可进一步提高诊断的特异性。     

Expression of thymidylate synthase in human cells is an early G(1) event regulated by CDK4 and p16INK4A but not E2F

Thymidylate synthase (TS) is the enzyme that catalyses the last step in de novo thymidylate synthesis. It is of interest clinically because it is an effective target for drugs such as 5-fluorouracil, often used in combination therapy. Despite a number of earlier reports indicating that TS is a cell cycle-dependent enzyme, this remains equivocal. Here, we show that in HCT116 cells synchronised by serum starvation, there is a clear dissociation between the expression of cyclin E (a well-characterised cell-cycle protein) and TS. Although both cyclin E and TS mRNA and protein increased during G(1), TS upregulation was delayed. Moreover, TS levels did not decrease following S-phase completion while cyclin E decreased sharply. Similarly, clear differences were seen between cyclin E and TS as asynchronously growing HCT116 cells were growth-inhibited by low-serum treatment. In contrast to previous reports using rodent cells, adenovirus-mediated over-expression of E2F1 and cyclin E in three human cell lines had no effect on TS. Cell-cycle progression was blocked by treatment of cells with pharmacological inhibitors of CDK2 and CDK4 and by ectopic expression of p16INK4A. Whereas CDK2 inhibition had no effect on TS levels, inhibition of CDK4 was associated with decreased TS protein levels. These results provide the first evidence that drugs targeting CDK4 may be useful with anti-TS drugs as combination therapy for cancer.     

Frat1与TCF4在非小细胞肺癌(NSCLC)中表达的相关性及意义

目的:研究Frat1与TCF4在NSCLC中的表达及其意义。方法:用免疫组化SP法对95例原发性NSCLC患者手术标本中Frat1和TCF4的表达进行检测。结果:在NSCLC中Frat1表达与肺癌组织的低分化、淋巴结转移、TNM分期相关(P<0.05);TCF4的表达与淋巴结转移、TNM分期相关(P<0.05);Frat1的表达与TCF4的表达有相关性(P<0.05)。结论:Frat1和TCF4在NSCLC中与肺癌的侵袭和转移等恶性表型有关,Frat1和TCF4在癌组织中的表达有相关性。