CCNE1 Expression Research Articles

Uncovering the Pharmacological Mechanism of 2-Dodecyl-6-Methoxycyclohexa-2,5 -Diene-1,4-Dione Against Lung Cancer Based on Network Pharmacology and Experimental Evaluation.

Background: 2-Dodecyl-6-Methoxycyclohexa-2, 5-Diene-1,4-Dione (DMDD) was purified from the roots of Averrhoa carambola L. Previous research demonstrated that DMDD is a small molecular compound with significant therapeutic potential for tumors. However, the potential targets and pharmacological mechanism of DMDD to treat lung cancer has not been reported. Methods: We employed network pharmacology and experimental evaluation to reveal the pharmacological mechanism of DMDD against lung cancer. Potential therapeutic targets of DMDD were screened by PharmMapper. Differentially expressed genes (DEGs) in The Cancer Genome Atlas (TCGA) lung cancer data sets were extracted and analyzed by GEPIA2. The mechanism of DMDD against lung cancer was determined by PPI, gene ontology (GO) and KEGG pathway enrichment analysis. Survival analysis and molecular docking were employed to obtain the key targets of DMDD. Human lung cancer cell lines H1975 and PC9 were used to detect effects of DMDD treatment in vitro. The expression of key targets after DMDD treated was validated by Western Blot. Results: A total of 60 Homo sapiens potential therapeutic targets of DMDD and 3,545 DEGs in TCGA lung cancer datasets were identified. Gene ontology and pathway analysis revealed characteristic of the potential targets of DMDD and DEGs in lung cancer respectively. Cell cycle and pathways in cancer were overlapping with DMDD potential targets and lung cancer DEGs. Eight overlapping genes were found between DMDD potential therapeutic targets and lung cancer related DEGs. Survival analysis showed that high expression of DMDD potential targets CCNE1 and E2F1 was significantly related to poor patient survival in lung cancer. Molecular docking found that DMDD exhibited significant binding affinities within the active site of CCNE1 and E2F1. Further tests showed that DMDD inhibited the proliferation, migration and clone formation in lung cancer cell lines (H1975 and PC9) in a dose and time dependent manner. Mechanistically, DMDD treatment decreased the expression of CDK2, CCNE1, E2F1 proteins and induced cell cycle arrest at the G1/S phase in H1975 and PC9 cells. Conclusion: These results delineated that DMDD holds therapeutic potential that blocks tumorigenesis by cell cycle regulation in lung cancer, and may provide potential therapies for lung cancer.

Ectopic expression of microRNA-874 represses epithelial mesenchymal transition through the NF-κB pathway via CCNE1 in cholangiocarcinoma

Cholangiocarcinoma (CC) is a devastating disease associated with poor survival rate. microRNAs (miRNAs) have recently been reported to assume a great role in CC development. This research aims to explore the functions of miR-874 in regulating epithelial mesenchymal transition (EMT) in CC. In obtained CC tissues and cells, miR-784 expression was assessed by RT-qPCR, and CCNE1 expression by RT-qPCR or immunohistochemistry. Dual-luciferase reporter assay was implemented for relationship between miR-784 and CCNE1. The roles of miR-784, CCNE1 and the NF-κB pathway in CC were investigated on human CC cell lines. CCNE1 was found to be highly expressed in CC while miR-874 expression was lowered in CC tissues and cells, thereby suggesting a negative regulatory effect of CCNE1. In QBC939 and RBE cells, overexpressing miR-874 or silencing CCNE1 led to augmented IκBα and E-cadherin expression, but diminished CCNE1, NF-κB, N-cadherin, and Vimentin expression. Moreover, overexpression of miR-874 or CCNE1 silencing led to reduced cell proliferation, invasion, and migration capabilities. In conclusion, we demonstrated that miR-874 negatively regulated CCNE1 to inhibit the NF-κB pathway, thus consequently suppressing EMT in CC. Therefore, the overexpression of miR-874 might bring favorable outcomes for the treatment of CC.

Silencing of long noncoding RNA MYLK-AS1 suppresses nephroblastoma via down-regulation of CCNE1 through transcription factor TCF7L2.

Nephroblastoma, a pediatric kidney cancer, caused by pluripotent embryonic renal precursors. Long noncoding RNAs (lncRNAs) are commonly abnormal expressed in many cancers. In the present study, we fousced on one newly discrovered lncRNA, MYLK Antisense RNA 1 (MYLK-AS1), and its functional role in proliferation and cycle distribution of nephroblastoma cells. Micorarray-based analysis revealed the highly expressed Cyclin E1 (CCNE1) and MYLK-AS1 in nephroblastoma. After nephroblastoma tissue sample collection, RT-qPCR confirmed the upregulated expression of MYLK-AS1 and CCNE1 in nephroblastoma tissues and cells. Kaplan-Meier curve exhibited that patients with elevated CCNE1 had lower overall survival rate in follow-up study. RNA binding protein immunoprecipitation, chromatin immunoprecipitation, and dual-luciferase reporter gene assay were employed to determine the relationship among MYLK-AS1, TCF7L2, and CCNE1, which validated that transcription factor 7-like 2 (TCF7L2) could specifically bind to MYLK-AS1 and TCF7L2 could positively promote CCNE1. After gain- and loss-of function assays, the conclusion that silencing of MYLK-AS1 could inhibit expression of CCNE1 through the transcription factor TCF7L2 to regulate the cell proliferation and cell cycle distribution of nephroblastoma cells was obtained. Subsequently, the subcutaneous tumor formation ability of nephroblastoma cell in nude mice was observed and the silencing of MYLK-AS1 exerts suppressive role in the tumorigenic ability of nephroblastoma cells in vivo. Taken together, MYLK-AS1 constitutes a promising biomarker for the early detection and treatment of nephroblastoma.

Regulatory Effect of miR497-5p-CCNE1 Axis in Triple-Negative Breast Cancer Cells and Its Predictive Value for Early Diagnosis.

ObjectiveTo explore the regulatory role of miR497-5p–CCNE1 axis in triple-negative breast cancer (TNBC) cells and its predictive value for early diagnosis.MethodsCancer tissue and adjacent tissue samples were collected from 86 patients with TNBC.RT-PCR was used to detect the expression of miR497-5p and CCNE1 (target gene) mRNA, determined by biological prediction in tissue and TNBC cells. ROC was used to analyze the diagnostic value of miR497-5p in TNBC. MTT, invasion, and flow cytometry were used to detect the proliferation, invasion, cycle, apoptosis rate, and expression of related proteins of TNBC cells with overexpression of miR497-5p or knockdown of CCNE1.ResultsRT-qPCR results showed that miR497-5p levels were significantly downregulated in TNBC tissue and cells, while CCNE1 expression was significantly upregulated, and miR497-5p expression was negatively correlated with that of CCNE1 (P<0.001). ROC analysis showed that the AUC of miR497-5p for TNBC was >0.9, which had better diagnostic value. The cell tests revealed that miR497-5p played a role in tumor inhibition, including inhibiting proliferation and invasion of TNBC cells, blocking the cell cycle, and promoting apoptosis. Bioinformatic prediction and subsequent experiments revealed that CCNE1 was the direct target of miR497-5p. Furthermore, after knocking down the expression of CCNE1 in TNBC cells, the proliferation and invasion of TNBC cells were significantly inhibited, the cell cycle blocked, and the apoptosis rate significantly increased (P<0.001), and expression of the proapoptosis-related proteins Bax and caspase 3 (cleaved) were upregulated, while expression of the antiapoptosis-related protein BCL2 was downregulated (P<0.001).ConclusionmiR497-5p inhibited the proliferation and invasion of TNBC cells by targeting CCNE1, blocked the cell cycle and promoted the apoptosis of TNBC cells, and had better diagnostic value for TNBC. miR497-5p can be used as a new potential target for the treatment of TNBC.

E2F transcription factor 1 (E2F1) promotes the transforming growth factor TGF-β1 induced human cardiac fibroblasts differentiation through promoting the transcription of CCNE2 gene

ABSTRACT The differentiation of cardiac fibroblast to myofibroblast is the key process of cardiac fibrosis. In the study, we aimed to determine the function of E2F Transcription Factor 1 (E2F1) in human cardiac fibroblasts (HCFs) differentiation, search for its downstream genes and elucidate the function of them in HCFs differentiation. As a result, we found that E2F1 was up-regulated in TGF-β1-induced HCFs differentiation. Silencing the expression of E2F1 by siRNA in HCFs, we found that the expression of differentiation-related genes (Collagen-1, α-Smooth muscle actin, and Fibronectin-1) was significantly suppressed, combining with proliferation and migration assay, we determined that HCFs differentiation was decreased. Luciferase report assay and immunoprecipitation proved that the oncogene CCNE2 was a direct target gene of E2F1, overexpression of CCNE2 was found in differentiated HCFs, silencing the expression of CCNE2 by siRNA decreased HCFs differentiation. Our research suggested that E2F1 and its downstream target gene CCNE2 play a vital role in TGF-β1-induced HCFs differentiation, thus E2F1 and CCNE2 may be a potential therapeutic target for cardiac fibrosis.

MiR-193b enhanced proliferation and migration and inhibits apoptosis through targeting RAB7A in osteosarcoma cell

Accumulating study indicated that microRNA (miRNA) played critical role in the osteosarcoma (OS). The role and mechanisms of miR-193b in OS cell lines were still unknown. We resolved the miR-193b expression in OS cell line and normal cell by RT-PCR assay. The effects of upregulated miR-193b on OS cell proliferation, migration, invasion and apoptosis were evaluated using CCK-8 assay, transwell assay, would-healing assay and flow cytometric analysis in vitro, respectively. We investigated the effect of upregulated miR-193b on the mRNA level of cell cycle protein CCND1 and CCNE1 using RT-PCR assay and the protein level of epithelial to mesenchymal transition (EMT)-related protein E-cadherin, vimentin, and N-cadherin by western blotting assay in MG-63 and U2SO cells. Furthermore, luciferase reporter assays were employed to identify the candidate target gene RAB7A of miR-193b. The expression of miR-193b was downregulated in OS cells. In MG-63 and U2SO cells, ectopic miR-193b expression inhibited cell proliferation, migration, invasion, and induced apoptosis. We found that miR-193b reduced the mRNA expression of CCND1 and CCNE1, and regulated the associated proteins of EMT including E-cadherin, vimentin and N-cadherin in MG-63and U2SO cell lines. Moreover, the candidate target gene RAB7A was negatively regulated by miR-193b. In addition, upregulated RAB7A rescued the inhibitory effect of miR-193b mimics on the development of OS cell. In conclusion, this study suggested that miR-193b overexpression inhibited cell proliferation, migration, invasion, and induced cell apoptosis by down-regulating RAB7A in OS cell lines.

The immune and metabolic changes with age in giant panda blood by combined transcriptome and DNA methylation analysis.

Giant panda (Ailuropoda melanoleuca) is an endangered mammalian species. Exploring immune and metabolic changes that occur in giant pandas with age is important for their protection. In this study, we systematically investigated the physiological and biochemical indicators in blood, as well as the transcriptome, and methylation profiles of young, adult, and old giant pandas. The white blood cell (WBC), neutrophil (NEU) counts and hemoglobin (HGB) concentrations increased significantly with age (young to adult), and some indicators related to blood glucose and lipids also changed significantly with age. In the transcriptome analysis, differentially expressed genes (DEGs) were found in comparisons of the young and adult (257), adult and old (20), young and old (744) groups. Separation of the DEGs into eight profiles according to the expression trend using short time-series expression miner (STEM) software revealed that most DEGs were downregulated with age. Functional analysis showed that most DEGs were associated with disease and that these DEGs were also associated with the immune system and metabolism. Furthermore, gene methylation in giant pandas decreased globally with age, and the expression of CCNE1, CD79A, IL1R1, and TCF7 showed a highly negative correlation with their degree of methylation. These results indicate that the giant panda's immune function improves gradually with age (young to adult), and that changes in the methylation profile are involved in the effects of age on immune and metabolic functions. These results have important implications for the understanding and conservation of giant pandas.

Research on the Potential Mechanism of Gentiopicroside Against Gastric Cancer Based on Network Pharmacology.

BackgroundGastric cancer was still one of the commonly diagnosed cancer types and the third-most common cause of cancer-related death in the world. Gentiopicroside, which is extracted from the Gentianella acuta, is commonly used in both traditional treatment and modern clinical care; therefore, its anticancer effects have been attracted more attention. However, the systematic analysis of action mechanism of Gentiopicroside on gastric cancer (GC) has not yet been carried out.AimA network pharmacology-based strategy combined with molecular docking studies and in vitro validation was employed to investigate potential targets and molecular mechanism of Gentiopicroside against GC.Materials and MethodsPotential targets of Gentiopicroside, as well as related genes of GC, were acquired from public databases. Potential targets, and signaling pathways were determined through bioinformatic analysis, including protein–protein interaction (PPI), the Gene Ontology (GO), and the Kyoto Encyclopedia of Genes and Genomes (KEGG). Subsequently, molecular docking and cell experiments were performed to further verify the above findings.ResultsOur findings revealed that the anticancer activity of Gentiopicroside potentially involves 53 putative identified target genes. In addition, GO, KEGG, and network analyses revealed that these targets were associated with cell proliferation, metabolic process, and other physiological processes. Furthermore, we have proved that critical compound affected the expression of CCND1, CCNE1, p-AKT and p-P38 at protein levels. These findings provide an overview of the anticancer action of Gentiopicroside from a network perspective; meanwhile, it might also set an example for future studies of other materials used in traditional Chinese medicine (TCM).ConclusionThis study comprehensively illuminated the potential targets and molecular mechanism of Gentiopicroside against GC. It also provided a promising approach to uncover the scientific basis and therapeutic mechanism of TCM treating for disease.

Clinical significance of CCNE2 protein and mRNA expression in thyroid cancer tissues

PurposeThyroid carcinoma (TC) is the most common endocrinal malignancy worldwide. Cyclin E2 (CCNE2), a member of the cyclin family, acts as a regulatory subunit of cyclin-dependent kinases (CDKs). It controls the transition of quiescent cells into the cell cycle, regulates the G1/S transition, promotes DNA replication, and activates CDK2. This study explored the role and potential molecular mechanisms of CCNE2 expression in TC tissues. Material/methodsImmunohistochemistry was used to evaluate the CCNE2 protein expression levels in TC. High-throughput data on CCNE2 in TC were obtained from RNA sequencing (RNA-seq), microarray, and literature data. The CCNE2 expression levels in TC were comprehensively assessed through an integrated analysis. Analyses of Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein–protein interaction (PPIs) data facilitated the investigation of the relative molecular mechanisms of CCNE2 in TC. ResultsThe immunohistochemical experiment showed a significant increase in the expression of CCNE2 in the TC tissues. For 505 TC and 59 non-cancerous samples from RNA-seq data, the area under the curve (AUC) was 0.8016 (95% confidence interval [CI] 0.742–0.8612; p<0.001). With another 14 microarrays, the pool standard mean difference [SMD] was 1.01 (95% CI [0.82–1.19]). The pooled SMD of CCNE2 was 1.12 (95% CI [0.60–1.64]), and the AUC was 0.87 (95% CI [0.84–0.90]) for 1157 TC samples and 366 non-cancerous thyroid samples from all possible sources. Nine hub genes were upregulated in TC. ConclusionsA high expression of CCNE2 may lead to carcinogenesis and the development of TC.

CircDENND2A Promotes Non-small Cell Lung Cancer Progression via Regulating MiR-34a/CCNE1 Signaling.

The mechanism regulating non-small cell lung cancers (NSCLCs) is unclear. In this study, we aimed to determine the roles of DENN domain containing 2A (circDENND2A) in the progression of NSCLC. Circular RNAs (circRNAs) are composited by “head to tail” splicing of coding or non-coding RNAs (ncRNAs), whose crucial roles in human cancers had been revealed. CircDENND2A, a new circRNA, was revealed to induce cell proliferation and migration. Our data indicated that circDENND2A was a probable oncogene in human cancers. However, the roles of circDENND2A in NSCLC remained unknown. Here, we demonstrated that circDENND2A was down-regulated in NSCLC samples. Loss-of-function assays showed circDENND2A knockdown suppressed cell growth via inducing cell cycle arrest and apoptosis and inhibited cell migration and invasion. Bioinformatics analysis and competing endogenous RNA (ceRNA) network analysis revealed that circDENND2A was involved in regulating cell cycle and tumor protein p53 (TP53) signaling via miR-34a/CCNE1 (cyclin E1). Further validation showed that circDENND2A could directly bind to miR-34a, promoting CCNE1 expression in NSCLC. In addition, rescue assays demonstrated that restoration of CCNE1 significantly impaired the suppressive effects of circDENND2A silencing in terms of NSCLC growth, migration, and invasion. We thought this study indicated that circDENND2A/miR-34a/CCNE1 may be a potential therapeutic target for NSCLC.

Paclitaxel inhibits proliferation and promotes apoptosis through regulation ROS and endoplasmic reticulum stress in osteosarcoma cell

Paclitaxel is a chemotherapeutic drug for cancer, which is isolated from the Pacific yew tree. However, and the molecular mechanism and the antitumor effects of paclitaxel on osteosarcoma cell remain to be explored. The aim of our study was to explore the possible molecular mechanisms of apoptosis in osteosarcoma induced by paclitaxel. Paclitaxel can obviously decrease the proliferation of HOS-732 cells in a dose-dependent manner. Paclitaxel could induce the cell cycle arrest at the G2/M-phase and decreases the CDK5 and CCNE1 expression in HOS-732 cells. Paclitaxel promotes cell apoptosis in HOS-732 cells, which may be contacted to the decreasing of Bcl-2 protein expression. Further, the production of ROS in HOS-732 cells was remarkably increased with the increasing concentration of paclitaxel. Moreover, paclitaxel induces the ER-stress related gene and protein expression (GRP79, DDIT3 mRNA and GRP78, XBP-1 s, IRE1α protein expression) in osteosarcoma cells. Paclitaxel can inhibit the proliferation of HOS-732 cells and increase ROS and ER-stress response to promote cell apoptosis, suggesting that paclitaxel may represent a new therapeutic option for the treatment and prevention osteosarcoma.

CARM1 promotes non-small cell lung cancer progression through upregulating CCNE2 expression.

The underlying molecular mechanisms of tumorigenesis and progression of non-small cell lung cancer (NSCLC) are not yet fully elucidated. In the present study, in vitro functional dissections suggest that siRNA-mediated silencing of CCNE2 profoundly attenuated the proliferative and colony-formative abilities of NSCLC PC9 and HCC827 cells, while forced overexpression of CCNE2 significantly strengthened the proliferative and colony-formative capabilities of these cells. Intriguingly, by ChIP and luciferase reporter gene assays, we observed that CARM1 is recruited to the promoter regions of CCNE2 gene and acts as a transcriptional activator. Mechanically, the asymmetric di-methylation of H3R17me2a and H3R26me2a, as the catalytic substrates of CARM1, were highly enriched at the core promoter regions of CCNE2 gene, thereby activating the expression of CCNE2. In vitro and in vivo rescue experiments demonstrated that restoration of CCNE2 expression significantly abolished the CARM1 shRNA-mediated inhibition of cell proliferation, indicating that the oncogenic function of CARM1, at least partially, depended on the activation of CCNE2. Inhibition of CARM1 enzymatic activity could significantly repress CCNE2 expression in NSCLC cells. In addition, the expression of CARM1 was significantly elevated and positively correlated with CCNE2 levels in 20 cases of NSCLC patients. Both CARM1 and CCNE2 are highly associated with shorter 10-year overall survival of at a large cohort of 461 cases of NSCLC patients from the Kaplan-Meier plotter database. To summarize, these findings provide compelling evidence that CARM1 could promote NSCLC progression via activation of CCNE2, paving the way for future therapeutic strategies in NSCLC.

Hepatoprotective effects of hydroxysafflor yellow A in D-galactose-treated aging mice

Hydroxysafflor yellow A (HSYA) is an effective chemical component isolated from Chinese herb Carthamus tinctorius L. In present study, we aimed to evaluate the effects of HSYA on D-galactose- (D-gal-) induced aging in mice, and to elucidate the underlying mechanism. Male C57BL/6 mice were intraperitoneal injection of D-gal and HSYA for 8 weeks. The body weight gain, spleen and thymus coefficients were determined. Levels of super dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in serum and liver were measured using commercial kits. Pathological changes and the SA-β-Gal activity in liver tissues were detected by hematoxylin and eosin and SA-β-Gal staining. The expression levels of p16, CDK4, CDK6 and phosphorylation levels of Retinoblastoma (Rb) were detected by immunohistochemistry and western blot analysis. mRNA levels of genes regulated by p16-Rb pathway were determined by quantitative real-time PCR. In vivo, HSYA improved the aging changes including body weight, organ index and antioxidant status such as activities of SOD, CAT, GSH-Px and MDA in D-gal treated aging mice. HSYA also dramatically attenuated pathologic changes of aging liver tissues induced by D-gal. Furthermore, HSYA significantly decreased the mRNA and protein level of cyclin-dependent kinase inhibitor p16, followed by increasing CDK4/6 protein expression and decreasing the phosphorylation of Retinoblastoma (pRb) which up-regulated the expression of downstream genes CCNE1, CCNA2, P107 and MCM4. Collectively, these data indicated that HSYA could ameliorate aging, especially hepatic replicative senescence resulting from D-gal, the mechanism could be associated with the suppression of p16-Rb pathway.

High-risk breast cancer genes at 8q22-24 and their role in over 5,000 patients evaluated with the 70-gene risk of recurrence assay.

3569 Background: Previous studies have shown that CCNE2 expression is higher in patients’ cancers resistant to CDK4/6 inhibitors. Increased expression of CCNE2, MTDH, or TSPYL5, genes contained within the 70-gene risk of distant recurrence signature (70GS), has also been implicated in breast oncogenesis, poor prognosis, and chemoresistance. These genes are located on chromosome region 8q22.1, one of the most recurrently amplified regions out of all 70GS genes in breast tumors (Fatima et al. 2017). MYC, located on 8q24, is overexpressed in 40% of all breast cancers (BC). Here we examined the expression of CCNE2, MTDH, and TSPYL5 in relation to 70GS risk and the 80-gene molecular subtype signature (80GS), and their correlation with MYC expression in early stage BC patients. Methods: CCNE2, MTDH, TSPYL5, and MYC mRNA expression was measured in 5022 BC samples sent to Agendia (Irvine, CA) for 70GS and 80GS testing, which included FFPE microarray full-transcriptome data. 70GS was used to stratify patients into Ultra Low Risk (UL), Low Risk (LR), High Risk (HR), and Ultra High Risk (UH). Both 70GS and 80GS were used to classify patient samples into Luminal A, Luminal B, HER2, or Basal type. Wilcoxon rank sum test was used to assess expression differences. Results: The expression of CCNE2, MTDH, and TSPYL5 significantly correlated with each other and was higher in HR patients compared to LR patients (p &lt; 0.001) and higher in UH patients compared to HR patients (p &lt; 0.001). Expression of these genes was highest in Basal type tumors, 83% of which were UH, followed by Luminal B type tumors, and lowest in Luminal A type tumors. CCNE2 and MYC expression was elevated in LR compared to UL patients (p &lt; 0.001 and p = 0.0043). There was no difference in MYC expression between HR vs. LR or UH vs. HR. Lastly, there was no association between the expression of 8q22.1 genes and MYC in any 70GS subgroup. Conclusions: Within the 70GS, CCNE2, MTDH, and TSPYL5 have similar expression patterns and when overexpressed may identify an UH cohort of BC. This observation, in addition to their physical proximity at 8q22.1 suggests a possible amplicon in this region. The highest expression of CCNE2, MTDH, and TSPYL5 associated with UH patients and is concordant with previous studies that support the role of these genes in BC metastasis. Furthermore, this analysis suggests MYC may not stratify patients based on metastatic potential. These data may be clinically relevant for stratifying patients in ongoing clinical trials evaluating response and resistance to targeted therapies in early stage BC.

Tumor genomic analysis for biomarker identification in a phase I trial of the Wee 1 inhibitor adavosertib (AZD1775).

3624 Background: Adavosertib, a first-in-class Wee1 kinase inhibitor, abrogates G2/M cell cycle arrest causing premature mitosis and DNA replication stress, yielding enhanced DNA damage. Here we report on potential biomarkers of response from tumor genomic analysis in patients (pts) with solid tumors treated with adavosertib. Methods: Adavosertib was administered once daily on days 1-5 and 8-12 of a 21-day cycle. RECIST 1.1 was used to evaluate clinical response. Paired tumor biopsies were obtained for RNASeq gene expression profiling (GEP) and for whole-exome sequencing (WES) to evaluate gene mutation and copy number amplification (CNA). Fold change (FC) was calculated to define gene overexpression. To identify the frequency of CNA and mRNA overexpression for the genomic biomarkers of interest, cBioPortal analysis using TCGA and MSK-IMPACT datasets was performed. Differential GEP analysis of tumor and paired normal tissue was performed using the gene expression profiling interactive analysis (GEPIA) interface (Tang et al. 2017). Results: Out of 35 pts evaluable for response, 6 (17%) had partial response (PR; 4 ovarian carcinoma [OVC], 2 endometrial carcinoma [EC]). The median duration of response was 5.2 months (range 4.0-23.1). Eighteen pts (51.4%) had stable disease. Genomic analysis of tumor biopsies was available for 9 pts; 7 of these pts were evaluable for response, and 3 had PR (2 OVC, 1 EC). WES revealed TP53 mutations in 6 pts (66.6%; 3 pts with PR, 2 with progressive disease,1 not evaluable). On WES, tumor Cyclin E1 ( CCNE1) CNA was present in 1 of 3 PR pts while tumors from all 3 PR samples showed relatively high CCNE1 expression by RNAseq (FC = 4.07). In the MSK-IMPACT 2017 dataset, CCNE1 CNA was identified in 1.8% of pts (194 of 10336); of which, OVC (10.3%) and EC (8.7%) had the highest incidence of CCNE1 CNAs. In separate tumor-specific (OVC, EC) TCGA datasets having CCNE1 overexpression and/or CNA, overlap in CCNE1 overexpression with CCNE1 CNA was 35.5% (OVC) and 25.2% (EC). Compared to normal ovarian/ endometrial tissues, GEPIA analysis revealed significantly higher CCNE1 mRNA expression in OVC (FC = 3.5) and EC (FC = 3.8). Conclusions: CCNE1alterations (overexpression and/or CNA) tend to be enriched in OVC and EC with a limited fraction showing both overexpression and CNA. Tumor genomic analysis of additional OVC and EC pts treated with adavosertib is required to determine whether CCNE1 mRNA overexpression, regardless of CCNE1 CNA, is a potential biomarker of response to this drug in these tumor types. Funded by NCI contract No. HHSN261200800001E. Clinical trial information: NCT01748825 .

Tumour kinome re-wiring governs resistance to palbociclib in oestrogen receptor positive breast cancers, highlighting new therapeutic modalities

Combination of CDK4/6 inhibitors and endocrine therapy improves clinical outcome in advanced oestrogen receptor (ER)-positive breast cancer, however relapse is inevitable. Here, we show in model systems that other than loss of RB1 few gene-copy number (CN) alterations are associated with irreversible-resistance to endocrine therapy and subsequent secondary resistance to palbociclib. Resistance to palbociclib occurred as a result of tumour cell re-wiring leading to increased expression of EGFR, MAPK, CDK4, CDK2, CDK7, CCNE1 and CCNE2. Resistance altered the ER genome wide-binding pattern, leading to decreased expression of ‘classical’ oestrogen-regulated genes and was accompanied by reduced sensitivity to fulvestrant and tamoxifen. Persistent CDK4 blockade decreased phosphorylation of tuberous sclerosis complex 2 (TSC2) enhancing EGFR signalling, leading to the re-wiring of ER. Kinome-knockdown confirmed dependency on ERBB-signalling and G2/M–checkpoint proteins such as WEE1, together with the cell cycle master regulator, CDK7. Noteworthy, sensitivity to CDK7 inhibition was associated with loss of ER and RB1 CN. Overall, we show that resistance to CDK4/6 inhibitors is dependent on kinase re-wiring and the redeployment of signalling cascades previously associated with endocrine resistance and highlights new therapeutic networks that can be exploited upon relapse after CDK4/6 inhibition.

PKMYT1 is associated with prostate cancer malignancy and may serve as a therapeutic target.

Prostate cancer (PCa) is the third most common malignancy worldwide. Novel and effective therapeutic targets are needed for PCa. The purpose of this study was to discover novel therapeutic targets for PCa by performing advanced analysis on PCa RNA sequencing (RNAseq) data from The Cancer Genome Atlas (TCGA). Weighted correlation-network analysis (WGCNA) was performed on the RNAseq data of tumor samples, and the module most relevant to the Gleason score was identified. Combining differential gene-expression analysis and survival analysis, we narrowed down potential therapeutic target genes and found that PKMYT1 might be one. Subsequently, functional studies (i.e., cell-proliferation assays, cell cycle analysis, and colony-formation assays) demonstrated that knockdown of PKMYT1 significantly inhibited the growth of PCa cells. Further investigation illustrated that PKMYT1 promoted the growth of PCa cells through targeting CCNB1 and CCNE1 expression. In addition, fostamatinib, an inhibitor of PKMYT1, effectively inhibited the proliferation of PCa cells. Taken together, our results suggest that PKMYT1 is a gene associated with malignancy of PCa and is a novel therapeutic target.

Antibiotic tigecycline inhibits cell proliferation, migration and invasion via down-regulating CCNE2 in pancreatic ductal adenocarcinoma.

Recently, many researches have reported that antibiotic tigecycline has significant effect on cancer treatment. However, biomedical functions and molecular mechanisms of tigecycline in human pancreatic ductal adenocarcinoma (PDAC) remain unclear. In the current study, we tried to assess the effect of tigecycline in PDAC cells. AsPC‐1 and HPAC cells were treated with indicated concentrations of tigecycline for indicated time, and then, MTT, BrdU and soft agar assay were used to test cell proliferation. The effect of tigecycline on cell cycle and cellular apoptosis was tested by cytometry. Migration and invasion were detected by wound healing assay and transwell migration/invasion assay. Expressions of cell cycle‐related and migration/invasion‐related protein were determined by using Western blot. The results revealed that tigecycline observably suppressed cell proliferation by inducing cell cycle arrest at G0/G1 phase and blocked cell migration/invasion via holding back the epithelial‐mesenchymal transition (EMT) process in PDAC. In addition, tigecycline also remarkably blocked tumorigenecity in vivo. Furthermore, the effects of tigecycline alone or combined with gemcitabine in vitro or on PDAC xenografts were also performed. The results showed that tigecycline enhanced the chemosensitivity of PDAC cells to gemcitabine. Interestingly, we found CCNE2 expression was declined distinctly after tigecycline treatment. Then, CCNE2 was overexpressed to rescue tigecycline‐induced effect. The results showed that CCNE2 overexpression significantly rescued tigecycline‐inhibited cell proliferation and migration/invasion. Collectively, we showed that tigecycline inhibits cell proliferation, migration and invasion via down‐regulating CCNE2, and tigecycline might be used as a potential drug for PDAC treatment alone or combined with gemcitabine.

Long noncoding RNA LINC01234 silencing exerts an anti-oncogenic effect in esophageal cancer cells through microRNA-193a-5p-mediated CCNE1 downregulation.

Long non-coding RNAs (lncRNAs) are transcribed pervasively in the genome and act to regulate chromatin remodeling and gene expression. Dysregulated lncRNA expression has been reported in many cancers, but the role of lncRNAs in esophageal cancer (EC) has so far remained poorly understood. In this study, we aimed to understand the effect of lncRNA LINC01234 on EC development through competitively binding to microRNA-193a-5p (miR-193a-5p). The Gene Expression Omnibus (GEO) database was used for microarray-based EC expression profiling. Gain- and loss-of-function analyses were carried out in human EC-derived Eca-109 and EC9706 cells. Expression analyses of miR-193a-5p, LINC01234, CCNE1, caspase-3, p21, Bax, cyclinD1 and Bcl-2 were performed using RT-qPCR and Western blotting. Cell proliferation, colony formation and apoptosis analyses were carried out using MTT, Hoechst 33258 and flow cytometry assays. A xenograft EC model in nude mice was used to evaluate in vivo tumor growth and CCNE1 expression. Microarray-based analyses revealed that LINC01234 expression was increased in primary EC samples, whereas that of miR-193a-5p was decreased. We found that CCNE1 was a target of miR-193a-5p and that LINC01234, in turn, sponges miR-193a-5p. After treatment with si-LINC01234 or miR-193a-5p mimic, EC cells (Eca-109 and EC9706) exhibited cyclinD1 and Bcl-2 downregulation, and caspase-3, p21, Bax and cleaved caspase-3 upregulation. LINC01234 silencing or miR-193a-5p upregulation resulted in decreased proliferation and colony formation, and increased apoptosis of EC cells. In addition, LINC01234 silencing or miR-193a-5p upregulation resulted in reduced in vivo EC tumor growth and CCNE1 expression in nude mice. We found that silencing of LINC01234 suppresses EC development by inhibiting CCNE1 through competitively binding to miR-193a-5p, which suggests that LINC01234 may represent a novel target for EC therapy.

Abstract P4-10-24: Cyclin E overexpression is associated with high risk 70 gene signature, and may indicate intrinsic resistance to CDK4/6 inhibitors

Abstract Background: The use of CDK4/6 inhibitors (CDK4/6i) is a promising therapeutic strategy for recurrent ER+, HER2- breast cancers that have escaped previous treatment targeting the endocrine pathway. A number of adjuvant and neoadjuvant trials with CDK4/6i in early breast cancer are also underway. However, no clear predictive biomarkers for resistance are available other than loss of the RB1 tumor suppressor gene. Cyclin E genes (CCNE1, CCNE2) play a critical role in cell cycle control with approximately 25% of breast cancer overexpressing CCNE2, and there is a significant correlation between CCNE2 and CCNE1 expression1,2,3. Furthermore, a positive correlation between expression of CCNE1 and resistance to CDK4/6i (i.e. palbociclib)4,5,6 has been reported in vitro and in a gene expression analysis from the PALOMA-3 trial. The 70-gene MammaPrint® (MP) signature is a prognostic assay that stratifies early-stage breast cancer (ESBC) patients into Low and High-risk of distant relapse. One of the 70 genes is CCNE2, shown to be associated with resistance to both endocrine therapy and CDK4 inhibition7. Considering the potential role of the Cyclin E genes as biomarker of resistance for CDK4/6i, we assessed the expression of CCNE2 in a large series of ESBCs with respect to their MP risk profile. Methods: The mRNA expression of CCNE2 (and CCNE1) was measured in a series of 5022 breast cancer samples for which FFPE microarray full-transcriptome data were available for testing. Intensities were Lowess normalized and log2 transformed. The 80-gene BluePrint (BP) profile8 was used in combination with MP to stratify patient samples based on their molecular subtype: Luminal A- (MP Low Risk, BP Luminal), Luminal B- (MP High Risk, BP Luminal), HER2- and Basal-type. Wilcoxon rank sum test was used to examine expression differences. Results: CCNE2 is significantly higher expressed in MP High risk compared to MP Low risk tumors when all samples are included (p &amp;lt;0.0001). When looking at the clinically ER positive BP Luminal group, CCNE2 is significantly higher expressed in the Luminal B compared to the Luminal A tumors (p &amp;lt;0.0001). However, we observe a broad distribution of CCNE2 expression within the Luminal group, indicating a biological diversity in both Luminal A and B tumors, which CCNE2 may help to further define. Specifically, Luminal B tumors have a range of CCNE2 expression with the highest levels being in the highest MP risk interval (Ultra High). Of importance, CCNE1 showed similar expression patterns as CCNE2. Conclusions: Our preliminary results show that MP could help in stratifying BP Luminal-type B tumors in subgroups with differential CCNE2 expression. Since increased CCNE1 expression is correlated with CDK4/6i resistance, and CCNE2 is a functionally-related gene whose expression correlates to some extent with CCNE1, it is reasonable to speculate that high CCNE2 expression and MP High Risk Luminal B may also correlate with CDK4/6i resistance, a testable hypothesis. This warrants additional analyses that integrate treatment response data to support and further investigate these observations. Our exploratory analysis also highlights the added value of a multi-gene signature profile versus single-gene testing as tool for patient stratification and treatment recommendation. Refernces: 1. Asghar U et al Nat Rev Drug Discov. 2015 2. Caldon C et al Cell Div. 2010 3. Payton M et al Oncogene. 2002 4. Turner N et al. J Clin Oncol. 2019 5. Chandarlapaty S et al J Clin Oncol. 2019 6. Guarducci C et al NPJ Br Cancer. 2018 7. Caldon CE et al Mol Cancer Ther. 2012 8. Krijgsman O et al BRCT 2012 Citation Format: Lorenza Mittempergher, Joe McKelley, Rajith Bhaskaran, Sahra Uygun, René Bernards, Laura J van 't Veer, Annuska M Glas, William Audeh. Cyclin E overexpression is associated with high risk 70 gene signature, and may indicate intrinsic resistance to CDK4/6 inhibitors [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-24.