Identification and characterization of the BmCyclin L1-BmCDK11A/B complex in relation to cell cycle regulation

Cyclin proteins are the key regulatory and activity partner of cyclin-dependent kinases (CDKs), which play pivotal regulatory roles in cell cycle progression. In the present study, we identified a Cyclin L1 and 2 CDK11 2 CDK11 splice variants, CDK11A and CDK11B, from silkworm, Bombyx mori. We determined that both Cyclin L1 and CDK11A/B are nuclear proteins, and further investigations were conducted to elucidate their spatiofunctional features. Cyclin L1 forms a complex with CDK11A/B and were co-localized to the nucleus. Moreover, the dimerization of CDK11A and CDK11B and the effects of Cyclin L1 and CDK11A/B on cell cycle regulation were also investigated. Using overexpression or RNA interference experiments, we demonstrated that the abnormal expression of Cyclin L1 and CDK11A/B leads to cell cycle arrest and cell proliferation suppression. Together, these findings indicate that CDK11A/B interacts with Cyclin L1 to regulate the cell cycle.     

Regulation of cell cycle by MDM2 in prostate cancer cells through Aurora Kinase-B and p21WAF1/CIP1 mediated pathways

Overexpression of MDM2 oncoprotein has been detected in a large number of diverse human malignancies and has been shown to play both p53-dependent and p53-independent roles in oncogenesis. Our study was designed to explore the impact of MDM2 overexpression on the levels of various cell cycle regulatory proteins including Aurora kinase-B (AURK-B), CDC25C and CDK1, which are known to promote tumor progression and increase metastatic potential. Our data from human cell cycle RT² profiler PCR array experiments revealed significant changes in the expression profile of genes that are involved in different phases of cell cycle regulation in LNCaP-MST (MDM2 transfected) prostate cancer cells. Our current study has demonstrated a significant increase in the expression level of AURK-B, CDC25C, Cyclin A2, Cyclin B and CDK1 in LNCaP-MST cells as compared with wild type LNCaP cells that were modulated by MDM2 specific inhibitor Nutlin-3. In fact, the expression levels of the above- mentioned proteins were significantly altered at both mRNA and protein levels after treating the cells with 20 μM Nutlin-3 for 24 h. Additionally, the pro-apoptotic proteins including p53, p21, and Bax were elevated with the concomitant decrease in the key anti-apoptotic proteins following MDM2 inhibitor treatment. Also, Nutlin-3 treated cells demonstrated caspase-3 activation was observed with an in-vitro caspase-3 fluorescent assay performed with caspase 3/7 specific DEVD-amc substrate. Our results offer significant evidence towards the effectiveness of MDM2 inhibition in causing cell cycle arrest via blocking the transmission of signals through AURKB-CDK1 axis and inducing apoptosis in LNCaP-MST cancer cells. It is evident from our data that MDM2 overexpression probably is the primary cause for CDK1 up-regulation in the LNCaP-MST cells, which might have occurred possibly through activation of AURK-B. However, further studies in this direction should shed more light on the intracellular mechanisms involved in the regulation of Aurora kinase-B and CDK1 axis in MDM2 positive cancers.     

MicroRNA‐206 induces G1 arrest in melanoma by inhibition of CDK4 and Cyclin D

Expression profiling of microRNAs in melanoma lesional skin biopsies compared with normal donor skin biopsies, as well as melanoma cell lines compared with normal melanocytes, revealed that hsa‐miR‐206 was down‐regulated in melanoma (?75.4‐fold, P = 1.7 × 10^?4). MiR‐206 has been implicated in a large number of cancers, including breast, lung, colorectal, ovarian, and prostate cancers; however, its role in tumor development remains largely unknown, its biologic function is poorly characterized, and its targets affecting cancer cells are largely unknown. MiR‐206 reduced growth and migration/invasion of multiple melanoma cell lines. Bioinformatics identified cell cycle genes CDK2, CDK4, Cyclin C, and Cyclin D1 as strong candidate targets. Western blots and 3′UTR reporter gene assays revealed that miR‐206 inhibited translation of CDK4, Cyclin D1, and Cyclin C. Additionally, hsa‐miR‐206 transfection induced G1 arrest in multiple melanoma cell lines. These observations support hsa‐miR‐206 as a tumor suppressor in melanoma and identify Cyclin C, Cyclin D1, and CDK4 as miR‐206 targets.     

Cyclin T1 overexpression induces malignant transformation and tumor growth

Human PTEFb is a protein kinase composed by CDK9 and Cyclin T that controls the elongation phase of RNA Pol II. This complex also affects the activation and differentiation program of lymphoid cells. In this study we found that several head and neck tumor cell lines overexpress PTEFb. We also established that Cyclin T1 is able to induce transformation in vitro, as we determined by foci and colony formation assays. Nu/nu mice s.c. injected with stable transfected Cyclin T1 cells (NIH 3T3 Cyclin T1) developed tumors faster than animals injected with control cells (NIH 3T3 β-gal). In vitro, NIH 3T3 Cyclin T1 cells show increased proliferation and CDK4-Rb phosphorylation. Even more, silencing E2F1 expression (shRNA E2F1) in NIH 3T3 cells resulted in a dramatic inhibition of Cyclin T1-induced foci. All these data demonstrate for the first time the Cyclin T1 oncogenic function and suggest a role for this protein in controlling cell cycle probably via Rb/E2F1 pathway.Key words: cyclin T1, CDK9, PTEFb     

葡萄糖6-磷酸脱氢酶调控细胞周期蛋白E1和细胞周期蛋白依赖性激酶2促进细胞增殖及其在肾透明细胞癌中的预后价值

肾透明细胞癌(clear cell renal cell carcinoma,ccRCC)是一种转移率高、预后差的细胞代谢性疾病,对其有效诊疗及预后分子标志物的研究十分重要。葡萄糖6-磷酸脱氢酶(glucose 6-phosphatedehydrogenase, G6PD)在ccRCC中高表达,并提示患者不良预后,其促进ccRCC细胞增殖的分子机制有待进一步揭示。本研究发现,降低G6PD可抑制细胞周期G₁/S期转化并显著抑制ccRCC细胞增殖。G6PD可在细胞水平调控G₁/S期转化及增殖相关因子Cyclin D1,CDK4,CDK6,Cyclin E1和CDK2基因表达。TCGA数据库分析结果表明,ccRCC 中Cyclin D1,Cyclin E1 和 CDK2的mRNA 水平显著升高,而CDK4表达无明显差异,CDK6表达却显著降低。相关性分析结果显示,G6PD与Cyclin D1呈显著负相关(P<0.0001),G6PD与CDK4,CDK6之间无显著相关性(P>0.05),G6PD与Cyclin E1(P<0.0001)以及CDK2(P<0.05)显著正相关。进一步免疫组化检测结果表明,Cyclin E1和 CDK2在ccRCC肿瘤组织中表达显著升高。生存预后分析结果显示,Cyclin D1高表达提示ccRCC患者整体预后更为良好,CDK4和CDK6表达水平在ccRCC患者总生存率预测中无意义;而Cyclin E1和CDK2高表达均可提示ccRCC患者预后不良。进一步细胞水平检测发现,Cyclin E1、CDK2表达降低可显著逆转G6PD促进ccRCC细胞增殖的能力。综上,与增殖相关因子Cyclin D1,CDK4和CDK6相比,G6PD有可能通过促进Cyclin E1和CDK2表达升高而发挥促进 ccRCC肿瘤细胞增殖的作用,并且这3者的异常高表达有望成为ccRCC患者不良预后的独立生存预测因素。     

miR-937-5p targets SOX17 to modulate breast cancer cell cycle and cell proliferation through the Wnt signaling pathway

Breast cancer is one of the most frequent cancers in women and the globally leading cause of cancer-related deaths. Bioinformatics and experimental analyses found that miR-937-5p may play a proto-oncogenic role in breast cancer; however, the specific effects and the molecular mechanism need further investigation. GSEA-KEGG and GSEA-GO suggested that miR-937-5p might be related to cell cycle and DNA replication. The experimental data indicated that miR-937-5p inhibition significantly repressed the proliferation of breast carcinoma cells and elicited S-phase cell cycle arrest. Meanwhile, the protein levels of proliferating marker ki-67 and cell cycle regulators Cyclin A2, Cyclin B1, CDK1, and Cyclin D1 were also decreased by miR-937-5p inhibition. miR-937-5p could directly bind to and negatively regulate SOX17. SOX17 overexpression also significantly repressed the proliferation of breast carcinoma cells and elicited S-phase cell cycle arrest and decreased ki-67, β-catenin, c-Myc, Cyclin A2, Cyclin B1, Cyclin D1, and CDK1 protein contents. More importantly, the effects of miR-937-5p were reversed by SOX17.     

Expression of CDK1Tyr15, pCDK1Thr161, Cyclin B1 (Total) and pCyclin B1Ser126 in Vulvar Squamous Cell Carcinoma and Their Relations with Clinicopatological Features and Prognosis

Cyclin B1-CDK1 complex plays an important role in the regulation of cell cycle. Activation of Cyclin B1 and CDK1 and the formation of the complex in G2/M are under multiple regulations involving many regulators such as isoforms of 14-3-3 and CDC25 and Wee1. Abnormal expression of Cyclin B1 and CDK1 has been detected in various tumors. However, to our knowledge no previous study has investigated Cyclin B1 and CDK1 in vulvar cancer. Therefore, we evaluated the statuses of CDK1^Tyr15, pCDK1^Thr161, Cyclin B1 (total) and pCyclin B1^Ser126 in 297 cases of vulvar squamous cell carcinomas by immunohistochemistry. Statistical analyses were performed to explore their clinicopathological and prognostic values. In at least 25% of tumor cases high expression of CDK1^Tyr15, pCDK1^Thr161, Cyclin B1 (total) and pCyclin B1^Ser126 was observed, compared to the low levels in normal vulvar squamous epithelium. Elevated levels of CDK1^Tyr15, pCDK1^Thr161, Cyclin B1 (total) and pCyclin B1^Ser126 were correlated with advanced tumor behaviors and aggressive features. Although CDK1^Tyr15, pCDK1^Thr161, Cyclin B1 (total) and pCyclin B1^Ser126 could not be identified as prognostic factors, combinations of (pCDK1^{Thr161 C+N} + 14-3-3σ^N), (pCDK1^{Thr161 C+N} + 14-3-3η^C), (pCDK1^{Thr161 C+N} + Wee1^C) and (pCDK1^{Thr161 C+N} + 14-3-3σ^N + 14-3-3η^C + Wee1^C) were correlated with disease-specific survival (p = 0.036, p = 0.029, p = 0.042 and p = 0.007, respectively) in univariate analysis. The independent prognostic significance of (pCDK1^{Thr161 C+N} + 14-3-3σ^N + 14-3-3η^C + Wee1^C) was confirmed by multivariate analysis. In conclusion, CDK1^Tyr15, pCDK1^Thr161, Cyclin B1 (total) and pCyclin B1^Ser126 may be involved in progression of vulvar squamous cell carcinoma. The combination of pCDK1^Thr161, 14-3-3σ, 14-3-3η and Wee1 was a statistically independent prognostic factor.     

沉默Smad4基因表达抑制猪卵巢颗粒细胞增殖并使细胞G_1期阻滞

Smad4是TGF-β/Smad信号通路的核心下游信号分子.为探明Smad4基因对猪卵巢颗粒细胞增殖及细胞周期的影响,采用RNA干扰技术,设计并合成猪Smad4基因的靶向小分子干扰RNA,由LipofectamineTMRNAiMix介导转染体外培养的猪卵巢颗粒细胞.应用实时荧光定量PCR检测Smad4mRNA的干扰效果,应用MTT法、流式细胞术检测细胞增殖和细胞周期的变化,同时应用荧光定量PCR检测转染前后CyclinD1、CyclinB、CyclinA2、CDK1、CDK2、CDK4等周期相关基因的mRNA表达量的变化.实验结果显示,靶向猪Smad4的特异性siRNA序列对Smad4mRNA表达的抑制率为79.85%(P0.01);沉默Smad4可以显著抑制猪卵巢颗粒细胞增殖,并且改变细胞周期分布,G0/G1期细胞比例显著高于各对照组(P0.05),S期细胞比例显著低于各对照组(P0.05),细胞分裂被阻滞;转染36h后CyclinD1、CDK1的mRNA表达量显著低于对照组,CyclinA2、CDK2、CDK4极显著低于对照组,CyclinB差异不显著.综上所述,Smad4是影响猪卵巢颗粒细胞增殖及细胞周期进程的重要基因之一.     

结直肠癌相关周期蛋白质研究进展

细胞周期蛋白是调控真核细胞有丝分裂时相的一类蛋白质,在肿瘤细胞的分裂增殖活动中同样起到十分重要的调控作用。在结直肠癌中,细胞周期蛋白的异常表达和调节失控十分常见。在结直肠癌相关周期蛋白的研究中,关于细胞周期蛋白Cyclin D1的研究最深入,可作为结直肠癌的一项诊断指标并作为其增殖程度的监测。近年来,随着周期蛋白Cyclin E、B1和周期蛋白依赖激酶Cdk1、Cdk4以及p21等在结直肠癌发生发展中的作用陆续得到一系列相关实验的初步证实,结直肠癌的研究不断向前推进,细胞周期蛋白必将为结直肠癌的治疗提供新的靶点。本文主要从细胞周期蛋白在结直肠癌中的表达、治疗效果这2个方面,介绍近年来结直肠癌相关周期蛋白的研究进展。     

siRNA-mediated knockdown against NUF2 suppresses pancreatic cancer proliferation in?vitro and in?vivo

NUF2 (NUF2, Ndc80 kinetochore complex component) plays an important role in kinetochore-microtubule attachment. It has been reported that NUF2 is associated with multiple human cancers. However, the functional role of NUF2 in pancreatic cancer remains unclear. In this study, we found that NUF2 expression was stronger in tumour tissues than in normal pancreatic tissues, and its overexpression could be related to poor prognosis. Moreover, NUF2 was highly expressed in several human pancreatic cancer cell lines. We took advantage of lentivirus-mediated siRNA (small interfering RNA) to suppress NUF2 expression in PANC-1 and Sw1990 cell lines aiming to investigate the role of NUF2 in pancreatic cancer. NUF2 silencing by RANi (RNA interference) reduced the proliferation and colony formation ability of pancreatic cancer cells in vitro. Cell cycle analysis showed that NUF2 knockdown induced cell cycle arrest at G0/G1 phase via suppression of Cyclin B1, Cdc2 and Cdc25A. More importantly, NUF2 silencing was able to alleviate in vivo tumourigenesis in pancreatic cancer xenograft nude mice. Collectively, the present study indicates that the siRNA-mediated knockdown against NUF2 may be a promising therapeutic method for the treatment of pancreatic cancer.     

KDM1A and KDM3A promote tumor growth by upregulating cell cycle-associated genes in pancreatic cancer

Pancreatic cancer is a highly malignant cancer of the pancreas with a very poor prognosis. Methylation of histone lysine residues is essential for regulating cancer physiology and pathophysiology, mediated by a set of methyltransferases (KMTs) and demethylases (KDMs). This study surveyed the expression of methylation regulators functioning at lysine 9 of histone 3 (H3K9) in pancreatic lesions and explored the underlying mechanisms. We analyzed KDM1A and KDM3A expression in clinical samples by immunohistochemical staining and searching the TCGA PAAD program and GEO datasets. Next, we identified the variation in tumor growth in vitro and in vivo after knockdown of KDM1A or KDM3A and explored the downstream regulators of KDM1A and KDM3A via RNA-seq, and gain- and loss-of-function assays. Eleven H3K9 methylation regulators were highly expressed in pancreatic cancer, and only KDM1A and KDM3A expression positively correlated with the clinicopathological characteristics in pancreatic cancer. High expression of KDM1A or KDM3A positively correlated with pathological grade, lymphatic metastasis, invasion, and clinical stage. Kaplan–Meier analysis indicated that a higher level of KDM1A or KDM3A led to a shorter survival period. Knockdown of KDM1A or KDM3A led to markedly impaired tumor growth in vitro and in vivo. Mechanistically, CCNA2, a cell cycle-associated gene was partially responsible for KDM1A knockdown-mediated effect and CDK6, also a cell cycle-associated gene was partially responsible for KDM3A knockdown-mediated effect on pancreatic cancer cells. Our study demonstrates that KDM1A and KDM3A are highly expressed in pancreatic cancer and are intimately correlated with clinicopathological factors and prognosis. The mechanism of action of KDM1A or KDM3A was both linked to the regulation of cell cycle-associated genes, such as CCNA2 or CDK6, respectively, by an H3K9-dependent pathway.     

Targeting Conformational Activation of CDK2 Kinase

Cyclin‐dependent kinases constitute attractive pharmacological targets for cancer therapeutics, yet inhibitors in clinical trials target the ATP‐binding pocket of the CDK and therefore suffer from limited selectivity and emergence of resistance. The more recent development of allosteric inhibitors targeting conformational plasticity of protein kinases offers promising perspectives for therapeutics. In particular tampering with T‐loop dynamics of CDK2 kinase would provide a selective means of inhibiting this kinase, by preventing its conformational activation. To this aim we engineered a fluorescent biosensor that specifically reports on conformational changes of CDK2 activation loop and is insensitive to ATP or ATP‐competitive inhibitors, which constitutes a highly sensitive probe for identification of selective T‐loop modulators. This biosensor was successfully applied to screen a library of small chemical compounds leading to discovery of a family of quinacridine analogs, which potently inhibit cancer cell proliferation, and promote accumulation of cells in S phase and G2. These compounds bind CDK2/ Cyclin A, inhibit its kinase activity, compete with substrate binding, but not with ATP, and dock onto the T‐loop of CDK2. The best compound also binds CDK4 and CDK4/Cyclin D1, but not CDK1. The strategy we describe opens new doors for the discovery of a new class of allosteric CDK inhibitors for cancer therapeutics.     

Downregulation of gas5 increases pancreatic cancer cell proliferation by regulating CDK6

Recent studies have revealed that long non-coding RNAs (lncRNAs) play important roles in cancer biology and that lncRNA gas5 (growth arrest-specific 5) regulates breast cancer cell growth. However, the role of gas5 in pancreatic cancer progression remains largely unknown. In the current study, we assay the expression level of gas5 in pancreatic cancer tissues and define the role of gas5 in the regulation of pancreatic cancer cell proliferation. We verify that the expression level of gas5 is significantly decreased in pancreatic cancer tissues compared with normal control. Overexpression of gas5 in pancreatic cancer cells inhibits cell proliferation, whereas gas5 inhibition induces a significant decrease in G0/G1 phase and an increase in S phase. We further demonstrate that gas5 negatively regulates CDK6 (cyclin-dependent kinase 6) expression in vitro and in vivo. More importantly, knockdown of CDK6 partially abrogates gas5-siRNA-induced cell proliferation. These data suggest an important role of gas5 in the molecular etiology of pancreatic cancer and implicate the potential application of gas5 in pancreatic cancer therapy.     

Knockdown of CDK2AP1 in Primary Human Fibroblasts Induces p53 Dependent Senescence

Cyclin Dependent Kinase-2 Associated Protein-1 (CDK2AP1) is known to be a tumor suppressor that plays a role in cell cycle regulation by sequestering monomeric CDK2, and targeting it for proteolysis. A reduction of CDK2AP1 expression is considered to be a negative prognostic indicator in patients with oral squamous cell carcinoma and also associated with increased invasion in human gastric cancer tissue. CDK2AP1 overexpression was shown to inhibit growth, reduce invasion and increase apoptosis in prostate cancer cell lines. In this study, we investigated the effect of CDK2AP1 downregulation in primary human dermal fibroblasts. Using a short-hairpin RNA to reduce its expression, we found that knockdown of CDK2AP1in primary human fibroblasts resulted in reduced proliferation and in the induction of senescence associated beta-galactosidase activity. CDK2AP1 knockdown also resulted in a significant reduction in the percentage of cells in the S phase and an accumulation of cells in the G1 phase of the cell cycle. Immunocytochemical analysis also revealed that the CDK2AP1 knockdown significantly increased the percentage of cells that exhibited γ-H2AX foci, which could indicate presence of DNA damage. CDK2AP1 knockdown also resulted in increased mRNA levels of p53, p21, BAX and PUMA and p53 protein levels. In primary human fibroblasts in which p53 and CDK2AP1 were simultaneously downregulated, there was: (a) no increase in senescence associated beta-galactosidase activity, (b) decrease in the number of cells in the G1-phase and increase in number of cells in the S-phase of the cell cycle, and (c) decrease in the mRNA levels of p21, BAX and PUMA when compared with CDK2AP1 knockdown only fibroblasts. Taken together, this suggests that the observed phenotype is p53 dependent. We also observed a prominent increase in the levels of ARF protein in the CDK2AP1 knockdown cells, which suggests a possible role of ARF in p53 stabilization following CDK2AP1 knockdown. Altogether, our results show that knockdown of CDK2AP1 in primary human fibroblasts reduced proliferation and induced premature senescence, with the observed phenotype being p53 dependent.     

Cyclin A2 mutagenesis analysis: a new insight into CDK activation and cellular localization requirements

Cyclin A2 is essential at two critical points in the somatic cell cycle: during S phase, when it activates CDK2, and during the G2 to M transition when it activates CDK1. Based on the crystal structure of Cyclin A2 in association with CDKs, we generated a panel of mutants to characterize the specific amino acids required for partner binding, CDK activation and subcellular localization. We find that CDK1, CDK2, p21, p27 and p107 have overlapping but distinct requirements for association with this protein. Our data highlight the crucial importance of the N-terminal α helix, in conjunction with the α3 helix within the cyclin box, in activating CDK. Several Cyclin A2 mutants selectively bind to either CDK1 or CDK2. We demonstrate that association of Cyclin A2 to proteins such as CDK2 that was previously suggested as crucial is not a prerequisite for its nuclear localization, and we propose that the whole protein structure is involved.     

血管内皮生长因子及其受体与Cyclin E-CDK2在肝癌发生发展过程中的表达变化

目的通过观察血管内皮生长因子(VEGF)及其受体和细胞周期蛋白E(Cyclin E)在肝癌模型大鼠肝脏中表达情况,探讨VEGF与细胞周期相关蛋白在肝癌发生发展过程中的作用。方法建立诱发性肝癌模型,采用酶联免疫吸附试验检测血清中VEGF量的变化,免疫组化技术检测VEGFR1、Cyclin E和细胞周期蛋白依赖性激酶(CDK2)的表达情况。结果血清中的VEGF含量在对照组中最低,在实验组中逐渐增多,以癌变期含量最高。VEGFR1、Cyclin E和CDK2蛋白表达的平均光密度值均随着肝癌的发生发展有增高的趋势,大鼠血清中的VEGF量与肝脏组织中VEGFR1、Cyclin E和CDK2蛋白表达的平均光密度值随着肝癌的发生发展呈正相关(r=0.834,F=42.1274,P<0.05)。结论 VEGF及其受体VEGFR1在肝癌发生发展中异常表达,促进肝癌的发生发展,可能与Cyclin E、CDK2细胞周期蛋白异常表达有关。     

Long non-coding RNA OIP5-AS1 promotes pancreatic cancer cell growth through sponging miR-342-3p via AKT/ERK signaling pathway

Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1), a long non-coding RNA (lncRNA), has been reported to link with the progression of some cancers. However, its biological functions and underlying molecular mechanisms in pancreatic cancer are largely unknown. The aim of this study was to investigate the role of lncRNA OIP5-AS1 in pancreatic cancer. Quantitative real-time PCR analysis revealed that OIP5-AS1 is highly expressed in pancreatic cancer tissues versus adjacent non-tumor tissues. In vitro functional assays showed that downregulation of OIP5-AS1 or overexpression of miR-342-3p inhibited the proliferation, decreased Ki67 expression, and induced cell cycle arrest in pancreatic cancer cells. The expression of cyclinD1, CDK4, and CDK6 was decreased by knockdown of OIP5-AS1. Moreover, we found that OIP5-AS1 acted as a miR-342-3p sponge to suppress its expression and function. Dual-luciferase assay confirmed the interaction of OIP5-AS1 and miR-342-3p and verified anterior gradient 2 (AGR2) as a direct target of miR-342-3p. Results showed that depletion of miR-342-3p abolished the inhibitory effects of OIP5-AS1 knockdown on pancreatic cancer cell growth. The expression of Ki67, AGR2, cyclinD1, CDK4, CDK6, p-AKT, and p-ERK1/2 was reversed by silencing of miR-342-3p in pancreatic cancer cells with OIP5-AS1 knockdown. Further, knockdown of OIP5-AS1 suppressed tumor growth in a xenograft mouse model of pancreatic cancer. OIP5-AS1 induced pancreatic cancer progression via activation of AKT and ERK signaling pathways. Therefore, we demonstrate that OIP5-AS1 functions as oncogene in pancreatic cancer and its downregulation inhibits pancreatic cancer growth by sponging miR-342-3p via targeting AGR2 through inhibiting AKT/ERK signaling pathway.