ZNF251 promotes the progression of lung cancer by activating ERK signaling

Aberrant activation of ERK signaling is a hallmark of lung cancer. Although constitutively activating mutations of EGFR and KRAS contribute to the hyperactivation of ERK1/2, other mechanisms remain elusive. In this study, the zinc finger protein ZNF251 was found to be upregulated in clinical lung cancer samples, and it promoted the growth of lung cancer cells and the growth of primary lung KPC cells from mouse models (Ad‐Cre, Kras^G12D, and P53^f/f). In studying the molecular mechanism, ZNF251 was found to inhibit the expression of dual‐specificity phosphatase 6, a negative regulator of ERK activation, by directly binding to its promoter region. Taken together, our data indicate the tumor‐promoting effects of ZNF251 in lung cancer and suggest that ZNF251 is a therapeutic target.     

PAK2通过调节ERK信号通路的活性促进肺癌细胞顺铂耐药

目的:探讨p21激活激酶2(PAK2)在非小细胞肺癌（NSCLC）中是否存在异常表达,以及是否影响肺癌细胞的顺铂敏感性。方法:采用免疫组化和Western blot（WB）方法检测NSCLC中PAK2的蛋白表达模式。利用PAK2-siRNA下调肺癌细胞系中PAK2的表达后,通过WB和细胞功能学实验等方法,明确PAK2对NSCLC细胞系增殖和侵袭能力的影响,并检测顺铂耐药前后的肺癌细胞系中PAK2的表达改变,及其对肺癌细胞顺铂敏感性的影响。结果:PAK2在NSCLC中呈现明显的胞浆强表达,并且其异常表达与肺癌的恶性表型相关;PAK2在顺铂耐药肺癌细胞中表达增强,抑制ERK活性后,PAK2的表达上调不能显著促进肺癌细胞对顺铂耐药。结论:PAK2在NSCLC中发挥着重要的促癌基因功能,并通过调节ERK信号通路的活性介导肺癌细胞系对顺铂耐药性。     

TRPV4通过调控MAPK/ERK信号通路促进卵巢癌细胞的增殖和迁移北大核心

目的:探讨TRPV4通过影响MAPK/ERK信号通路调控卵巢癌细胞的增殖与迁移。方法:RT-qPCR和Western Blot方法检测TRPV4在卵巢癌细胞系和正常卵巢上皮细胞中的表达差异;GEPIA在线数据库分析卵巢癌患者TRPV4表达水平和预后关系;敲低TRPV4,通过RT-qPCR和Western Blot检测转染效率;通过细胞计数试剂盒(CCK8)、克隆形成实验以及Transwell迁移实验检测TRPV4在卵巢癌发生发展过程中增殖及迁移作用;通过GSEA软件富集分析信号通路并用Western Blot验证卵巢癌细胞MAPK/ERK信号通路表达量变化。结果:在卵巢癌细胞及临床组织样本中,TRPV4表达量明显增高,TRPV4表达量较高的患者预后更差。siRNA转染卵巢癌HO8910和Caov3细胞后,与Control组相比,TRPV4 mRNA和蛋白表达显著降低;细胞增殖迁移能力显著减弱;WB实验结果显示ERK总量不变,磷酸化水平降低,进一步实验中证实:敲低TRPV4后,ERK信号通路中的关键蛋白(P90RSK、MEK1/2、MSK1)磷酸化水平降低。结论:TRPV4在卵巢癌细胞及组织中高表达,可能通过正向调控MAPK/ERK信号通路,促进卵巢癌细胞增殖迁移等功能。     

Blocking p38/ERK crosstalk affects colorectal cancer growth by inducing apoptosis in vitro and in preclinical mouse models

We recently demonstrated that p38α is required to maintain colorectal cancer (CRC) metabolism, as its inhibition leads to FoxO3A activation, autophagy, cell death, and tumor growth reduction both in vitro and in vivo. Here we show that inhibition of p38α is followed by TRAIL-mediated activation of caspase-8 and FoxO3A-dependent HER3 upregulation with consequent overactivation of the MEK-ERK1/2 survival pathway. p38α and MEK combined inhibition specifically induces apoptosis by enabling TRAIL signaling propagation through t-Bid and caspase-3, and fosters cell death in CRC cells and preclinical mouse models. Current MEK1-directed pharmacological strategies could thus be exploited, in combination with p38α inhibition, to develop new approaches for CRC treatment.     

IL-22 produced by cancer-associated fibroblasts promotes gastric cancer cell invasion via STAT3 and ERK signaling

Background:

Interleukin-22 (IL-22) has been recently highlighted owing to its biological significance in the modulation of tissue responses during inflammation. However, the role of IL-22 in carcinogenesis has remained unclear. Here, we investigated the pathophysiological significance of IL-22 expression in gastric cancer tissues and examined the mechanism by which IL-22 promotes gastric cancer cell invasion.

Methods:

Human gastric cancer specimens were analysed by immunohistochemistry for expression of IL-22 and IL-22 receptor 1 (IL-22R1). The effects of IL-22-induced STAT3 and ERK signalling on invasive ability of gastric cancer cells were examined using a small-interfering RNA system and specific inhibitors. AGS cells were co-cultured with cancer-associated fibroblasts (CAFs) from human gastric cancer tissues and assessed by invasion assay.

Results:

Interleukin-22 and its receptor were expressed in α-smooth muscle actin-positive stromal cells and tumour cells at the invasive front of gastric cancer tissues, respectively. The expression of IL-22 and IL-22R1 was significantly related to lymphatic invasion. Interleukin-22 treatment promoted the invasive ability of gastric cancer cells through STAT3 and ERK activation. The invasive ability of gastric cancer cells was significantly enhanced by co-culture with IL-22-expressing CAFs.

Conclusions:

Interleukin-22 produced by CAFs promotes gastric cancer cell invasion via STAT3 and ERK signalling.     

非小细胞肺癌ERK、AKT蛋白磷酸化的病理意义

目的:探讨非小细胞肺癌ERK、AKT蛋白磷酸化的病理意义。方法:免疫组织化学SP法检测90例非小细胞肺癌的p-ERK和p-AKT表达状况,分析二者表达与通路上游EGFR、KRAS、PI3K表达及患者部分临床病理参数间的相关关系。结果:非小细胞肺癌中,p-ERK表达阳性率为53.33%,其与患者的性别和吸烟史及肺腺癌的分化程度相关（P<0.05）。p-ERK表达与EGFR及KRAS表达均无显著相关关系（P>0.05）。p-AKT表达阳性率为56.67%,p-AKT表达与EGFR表达显著正相关（r=0.336,P<0.05）,但与PI3K表达无显著相关关系（P>0.05）。p-ERK与p-AKT表达显著正相关（r=0.292,P<0.05）。结论:非小细胞肺癌中可能存在ERK的自身激活,检测ERK与AKT蛋白的磷酸化状态可能对筛选EGFR-TKI治疗获益人群有所帮助。     

p38 mitogen-activated protein kinase signaling, ERCC1 expression, and viability of lung cancer cells from never or light smoker patients

BACKGROUND:

Expression of DNA‐repair proteins and activated mitogen‐activated protein kinases (MAPKs) may differ according to smoking status. The authors investigated whether p38 MAPK activity contributed to the viability of cisplatin in lung cancer cell lines from never or light smokers and to ERCC1 mRNA expression.

METHODS:

Activated p38 MAPK was tested as a predictor for ERCC1 levels in 117 lung adenocarcinomas. Cell viabilities of NCI‐H1975, NCI‐H1793, NCI‐H1650, and NCI‐H1651 cell lines, derived from never or light smokers, were measured after treatment with the p38 MAPK inhibitor SB202190 and cisplatin. The role of p38α (MAPK14) and p38β (MAPK11) isoforms and ERCC1 was evaluated using RNA interference.

RESULTS:

ERCC1 protein‐level expression was predicted by activated p38 MAPK in lung adenocarcinoma tissues. The p38‐specific inhibitor SB202190 strongly decreased cell viability (43%‐63%). SB202190 plus cisplatin significantly decreased cell viability in every cell line, including cisplatin‐resistant NCI‐H1793. Genetic inhibition, targeting both MAPK11 and MAPK14, reduced the viability of the different cell lines: down‐regulation of p38β accounted for most of this effect. Cisplatin's effect was greater after MAPK11 down‐regulation for NCI‐H1651, and MAPK14 down‐regulation for NCI‐H1650. In addition, both SB202190 and MAPK11 inhibition reduced excision repair cross‐complementing 1 mRNA levels.

CONCLUSIONS:

Lung cancer cells from never or light smokers rely on p38 MAPK signaling for survival. MAPK11 is involved in that pathway and might contribute to ERCC1 expression. Sensitization to cisplatin can be achieved by pharmacological inhibition of p38 MAPK signaling. Cancer 2012. © 2012 American Cancer Society.     

ANGPTL2/LILRB2 signaling promotes the propagation of lung cancer cells

Immune inhibitory receptors expressed on various types of immune cells deliver inhibitory signals that maintain the homeostasis of the immune system. Recently we demonstrated that leukocyte immunoglobulin-like receptor subfamily B member 2 (LILRB2) and its murine homolog, paired immunoglobulin-like receptor B (PIRB), are expressed on hematopoietic stem cells and acute myeloid leukemia stem cells and function in maintenance of stemness. Herein, we determined that both LILRB2 and its soluble ligand ANGPTL2 are highly expressed in non-small cell lung cancer (NSCLC) samples, and levels are adversely related to patient prognosis. Inhibition of LILRB2 expression in NSCLC cell lines, such as A549 cells, resulted in a dramatic decrease in proliferation, colony formation, and migration. Mechanistic analyses indicated that ANGPTL2 binds LILRB2 to support the growth of lung cancer cells and that the SHP2/CaMK1/CREB axis controls the proliferation of lung cancer cell lines. Our results suggest that signaling involving ANGPTL2 and LILRB2 is important for lung cancer development and represents a novel target for treatment of this type of cancer.     

MAPK 信号通路在肝细胞癌发生发展中的作用

丝裂原活化蛋白激酶（mitogen activated protein kinase,MAPK）信号通路对多种肿瘤的发生发展过程起着重要的调节作用。肝细胞癌（hepatocellular carcinoma,HCC）细胞的凋亡、增殖、侵袭和转移等过程与p38MAPK、ERK、JNK 等 MAPK 信号通路同样有密切联系。本文将从这三条信号转导通路对 MAPK 信号通路在 HCC 发生发展中的作用进行综述。     

PADI1 contributes to EMT in PAAD by activating the ERK1/2-p38 signaling pathway

BackgroundPeptidylarginine deiminase 1 (PADI1) has been reported to promote tumorigenesis in breast cancer. However, the functional role of PADI1 in pancreatic ductal adenocarcinoma (PAAD) has remained elusive until now.MethodsThe expression pattern of PADI1 in PAAD tissues and normal tissues was analyzed using The Cancer Genome Atlas (TCGA) dataset. A Kaplan-Meier curve analysis was performed to evaluate the prognostic value of PADI1 in PAAD patients. PADI1 was knocked down in CFPAN-1 and HPAC cells, and overexpressed in PANC-1 and Bxpc-3 cells by RNA interference. A wound-healing assay was performed to analyze relative cell migration distance. Cell migration and invasion were assessed by a Transwell assay. Related protein expression levels were measured by western blot and immunofluorescence.ResultsThe bioinformatics analysis showed that PADI1 was overexpressed in PAAD tissues and associated with a poor survival prognosis. The knockdown of PADI1 suppressed cell migration and invasion, and activated the ERK1/2-p38 signaling pathway in CFPAN-1 and HPAC cells. The overexpression of PADI1 produced the opposite results in PANC-1 and Bxpc-3 cells. Additionally, treatment with an MEK1/2 inhibitor significantly attenuated the effects of PADI1 knockdown on cell migration, invasion, the epithelial-mesenchymal transition (EMT) process, and p-ERK1/2 and p38 expression in CFPAN-1 and HPAC cells.ConclusionsOur data suggested that PADI1 may function as an oncogene in regulating metastasis in vitro in PAAD.     

Insulin promotes proliferation,survival, and invasion in endometrial carcinoma by activating the MEK/ERK pathway

The involvement of insulin in endometrial carcinoma (EC) was investigated using radioimmunoassay, Western blot, immunoprecipitation, MTT, and Annexin V-FITC/PI assays in tissue samples and cultured cells. Serum levels of insulin, p-p52Shc, p-p46Shc, Shc·Grb2 complexes, p-MEK, p-ERK, and cyclin D1 were elevated in patients with EC. Expression of key proteins in the MEK/ERK pathway, including p-p52Shc, Shc·Grb2 complexes, p-MEK, p-ERK, and cyclin D1, was significantly higher in patients with advanced FIGO stage, high grade, and lymph-node metastasis and correlated positively with serum insulin concentration. Insulin promotes Ishikawa 3-H-12 cell proliferation, survival, and invasion, and these effects induced by insulin were significantly blocked by MEK inhibitor PD98059. Insulin thus promotes EC cell proliferation, survival, and invasion via the MEK/ERK pathway.     

MicroRNA-490-5p靶向CDK1通过ERK信号通路参与胃癌细胞周期调控

目的:探讨miR-490-5p对胃癌细胞增殖与周期的调控作用和分子机制,以期为临床治疗胃癌提供新的有效靶点.方法:收集30例胃癌患者的胃癌组织及相应的癌旁组织标本;采用Real-time PCR法检测miR-490-5p和CDK1的表达水平;分析细胞周期相关蛋白 CDK1 与 miR-490-5p 的靶向关系.MTT法和流式细胞仪检测转染后胃癌细胞生长以及细胞周期情况.结果:与癌旁组织相比,胃癌组织中miR-490-5p的表达显著下调(P<0.001);转染 miR-490-5p mimics 的细胞中miR-490-5p的表达显著上调,而miR-490-5p inhibitors中miR-490-5p显著下降(均P<0.001);CDK1 是 miR-490-5p 的靶基因;下调miR-490-5p、上调CDK1能促进胃癌细胞的增殖能力及G1/S期的转化(均P<0.001).结论:通过上调miR-490-5p 可以抑制胃癌细胞的恶性增殖,减少CDK1表达,抑制 ERK信号途径,降低了G1/S期的转化速率,从而为胃癌诊断及治疗提供新靶标.