RESUMEN

Replication stress (RS) is a key trait of cancer cells, and a potential actionable target in cancer treatment. Accurate methods to measure RS in tumour samples are currently lacking. DNA fibre analysis has been used as a common technique to measure RS in cell lines. Here, we investigated DNA fibre analysis on fresh breast cancer specimens and correlated DNA replication kinetics to known RS markers and genomic alterations. Fresh, treatment-naïve primary breast cancer samples (n = 74) were subjected to ex vivo DNA fibre analysis to measure DNA replication kinetics. Tumour cell proliferation was confirmed by EdU incorporation and cytokeratin AE1/AE3 (CK) staining. The RS markers phospho-S33-RPA and γH2AX and the RS-inducing proto-oncogenes Cyclin E1 and c-Myc were analysed by immunohistochemistry. Copy number variations (CNVs) were assessed from genome-wide single nucleotide polymorphism (SNP) arrays. We found that the majority of proliferating (EdU-positive) cells in each sample were CK-positive and therefore considered to be tumour cells. DNA fibre lengths varied largely in most tumour samples. The median DNA fibre length showed a significant inverse correlation with pRPA expression (r = -0.29, p = 0.033) but was not correlated with Cyclin E1 or c-Myc expression and global CNVs in this study. Nuclear Cyclin E1 expression showed a positive correlation with pRPA levels (r = 0.481, p < 0.0001), while cytoplasmic Cyclin E1 expression exhibited an inverse association with pRPA expression (r = -0.353, p = 0.002) and a positive association with global CNVs (r = 0.318, p = 0.016). In conclusion, DNA fibre analysis performed with fresh primary breast cancer samples is feasible. Fibre lengths were associated with pRPA expression. Cyclin E1 expression was associated with pRPA and the percentage of CNVs. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Asunto(s)

Neoplasias de la Mama , Ciclina E , Replicación del ADN , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Femenino , Ciclina E/genética , Ciclina E/metabolismo , Replicación del ADN/genética , Polimorfismo de Nucleótido Simple , Proliferación Celular , Variaciones en el Número de Copia de ADN , Persona de Mediana Edad , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Anciano , ADN de Neoplasias/genética , ADN de Neoplasias/metabolismo , Adulto

RESUMEN

A-kinase anchoring protein 95 (AKAP95) functions as a scaffold for protein kinase A. Prior work by our group has shown that AKAP95, in coordination with Connexin 43 (Cx43), modulates the expression of cyclin D and E proteins, thus affecting the cell cycle progression in lung cancer cells. In the current study, we confirmed that AKAP95 forms a complex with Cx43. Moreover, it associates with cyclins D1 and E1 during the G1 phase, leading to the formation of protein complexes that subsequently translocate to the nucleus. These findings indicate that AKAP95 might facilitate the nuclear transport of cyclins D1 and E1. Throughout this process, AKAP95 and Cx43 collectively regulate the expression of cyclin D, phosphorylate cyclin E1 proteins, and target their specific ubiquitin ligases, ultimately impacting cell cycle progression.

RESUMEN

CIC-rearranged sarcoma (CRS) is a group of high-grade undifferentiated small round cell sarcomas examined as a separate entity in the current WHO classification; since it shows more aggressive clinical behavior and distinct morphological and molecular features compared to Ewing sarcoma (ES). As CCNE1 expression is associated with tumor growth in CIC::DUX4 sarcomas, we aimed to demonstrate the value of cyclin E1 expression in CRS. Cyclin E1 immunohistochemistry and break-apart FISH for EWSR1 and CIC gene rearrangements were performed on 3-mm tissue microarrays composed of 40 small round cell tumors. Five cases were classified as CRS, whereas 22 were ES and 13 were unclassified (EWSR1-/CIC-). Among all three diagnostic groups, we found cyclin E1 expression level to be higher in CRS (80 %) and unclassified groups (61.5 %) compared to ES (4.5 %, p < 0.001). In addition, high cyclin E1 expression levels were associated with higher mean age at diagnosis, presence of atypical histology and myxoid stroma, low CD99 expression, and presence of metastasis at diagnosis. The sensitivity and specificity of high cyclin E1 expression in detecting non-ES cases were 95.5 % and 66.7 %, respectively. However, the correlation between cyclin E1 expression level and survival was not statistically significant. This is the first study that shows cyclin E1 immunohistochemical expression in EWSR1-negative undifferentiated small cell sarcomas, particularly CRS.

Asunto(s)

Biomarcadores de Tumor , Ciclina E , Reordenamiento Génico , Proteínas Oncogénicas , Proteínas Represoras , Humanos , Masculino , Proteínas Oncogénicas/metabolismo , Proteínas Oncogénicas/genética , Femenino , Adulto , Ciclina E/metabolismo , Ciclina E/genética , Persona de Mediana Edad , Adolescente , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Adulto Joven , Niño , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Inmunohistoquímica/métodos , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patología , Sarcoma de Ewing/genética , Sarcoma/patología , Sarcoma/metabolismo , Sarcoma/genética , Sarcoma/diagnóstico , Hibridación Fluorescente in Situ/métodos , Anciano , Preescolar , Proteína EWS de Unión a ARN/genética , Proteína EWS de Unión a ARN/metabolismo , Sarcoma de Células Pequeñas/metabolismo , Sarcoma de Células Pequeñas/genética , Sarcoma de Células Pequeñas/patología , Sarcoma de Células Pequeñas/diagnóstico

RESUMEN

Overexpression of Cyclin E1 perturbs DNA replication, resulting in DNA lesions and genomic instability. Consequently, Cyclin E1-overexpressing cancer cells increasingly rely on DNA repair, including RAD52-mediated break-induced replication during interphase. We show that not all DNA lesions induced by Cyclin E1 overexpression are resolved during interphase. While DNA lesions upon Cyclin E1 overexpression are induced in S phase, a significant fraction of these lesions is transmitted into mitosis. Cyclin E1 overexpression triggers mitotic DNA synthesis (MiDAS) in a RAD52-dependent fashion. Chemical or genetic inactivation of MiDAS enhances mitotic aberrations and persistent DNA damage. Mitosis-specific degradation of RAD52 prevents Cyclin E1-induced MiDAS and reduces the viability of Cyclin E1-overexpressing cells, underscoring the relevance of RAD52 during mitosis to maintain genomic integrity. Finally, analysis of breast cancer samples reveals a positive correlation between Cyclin E1 amplification and RAD52 expression. These findings demonstrate the importance of suppressing mitotic defects in Cyclin E1-overexpressing cells through RAD52.

Asunto(s)

Ciclina E , Inestabilidad Genómica , Mitosis , Proteínas Oncogénicas , Proteína Recombinante y Reparadora de ADN Rad52 , Humanos , Ciclina E/metabolismo , Ciclina E/genética , Proteína Recombinante y Reparadora de ADN Rad52/metabolismo , Proteína Recombinante y Reparadora de ADN Rad52/genética , Proteínas Oncogénicas/metabolismo , Proteínas Oncogénicas/genética , Replicación del ADN , Línea Celular Tumoral , Daño del ADN , ADN/metabolismo , ADN/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología

RESUMEN

Oncogene-induced replication stress has been recognized as a major cause of genome instability in cancer cells. Increased expression of cyclin E1 caused by amplification of the CCNE1 gene is a common cause of replication stress in various cancers. Protein phosphatase magnesium-dependent 1 delta (PPM1D) is a negative regulator of p53 and has been implicated in termination of the cell cycle checkpoint. Amplification of the PPM1D gene or frameshift mutations in its final exon promote tumorigenesis. Here, we show that PPM1D activity further increases the replication stress caused by overexpression of cyclin E1. In particular, we demonstrate that cells expressing a truncated mutant of PPM1D progress faster from G1 to S phase and fail to complete licensing of the replication origins. In addition, we show that transcription-replication collisions and replication fork slowing caused by CCNE1 overexpression are exaggerated in cells expressing the truncated PPM1D. Finally, replication speed and accumulation of focal DNA copy number alterations caused by induction of CCNE1 expression was rescued by pharmacological inhibition of PPM1D. We propose that increased activity of PPM1D suppresses the checkpoint function of p53 and thus promotes genome instability in cells expressing the CCNE1 oncogene.

Asunto(s)

Neoplasias , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ciclina E/genética , Ciclina E/metabolismo , Inestabilidad Genómica , Proteína Fosfatasa 2C/genética , Proteína Fosfatasa 2C/metabolismo

RESUMEN

Background & Objectives: Serous ovarian carcinoma (SOC) is characterized by extreme genomic instability, chromosomal rearrangements and copy number variations (CNVs) leading to the development of early metastasis and chemo-resistance. The present study was designed to observe the role of CNVs of Cyclin E1 (CCNE1) and Epithelial cell transforming sequence- 2 (ECT2) genes and their encoded proteins in predicting the chemotherapeutic response in SOC patients. Methods: This observational analytical study was conducted at University of Health Sciences, Lahore, Pakistan from December 2019 till June 2022.The study included twenty-five SOC patients with resectable ovarian tumors and twenty-five control subjects. The patients were followed-up for six months for their response to chemotherapy. The CNVs in CCNE1 and ECT-2 genes were determined by real time PCR while serum levels of encoded proteins were determined in controls and cases, before and after six months of treatment, through ELISA. The response to chemotherapy was categorized as sensitive or resistant based on serum CA-125 levels and radiological scans. Results: The copy number variations in CCNE1 and ECT2 genes showed association with the clinic-pathological characteristics and chemotherapy response. Statistically significant difference was found between the mean pre-chemotherapy protein levels of CCNE1 in cases than controls (p-value <0.001) and between the mean pre and post-chemotherapy protein levels of CCNE1 and ECT2 (p-value <0.001) in SOC patients. Conclusion: The copy number variations of CCNE1 and ECT2 genes and their protein expression are positively associated with chemotherapeutic response in SOC patients.

RESUMEN

Limited evidence exists on the impact of spatial and temporal heterogeneity of high-grade serous ovarian cancer (HGSOC) on tumor evolution, clinical outcomes, and surgical operability. We perform systematic multi-site tumor mapping at presentation and matched relapse from 49 high-tumor-burden patients, operated up front. From SNP array-derived copy-number data, we categorize dendrograms representing tumor clonal evolution as sympodial or dichotomous, noting most chemo-resistant patients favor simpler sympodial evolution. Three distinct tumor evolutionary patterns from primary to relapse are identified, demonstrating recurrent disease may emerge from pre-existing or newly detected clones. Crucially, we identify spatial heterogeneity for clinically actionable homologous recombination deficiency scores and for poor prognosis biomarkers CCNE1 and MYC. Copy-number signature, phenotypic, proteomic, and proliferative-index heterogeneity further highlight HGSOC complexity. This study explores HGSOC evolution and dissemination across space and time, its impact on optimal surgical cytoreductive effort and clinical outcomes, and its consequences for clinical decision-making.

Asunto(s)

Neoplasias Ováricas , Femenino , Humanos , Neoplasias Ováricas/genética , Neoplasias Ováricas/cirugía , Neoplasias Ováricas/patología , Proteómica , Recurrencia Local de Neoplasia/genética

RESUMEN

BACKGROUND: Cyclin E1 (CCNE1) is a potential predictive marker and therapeutic target in tubo-ovarian high-grade serous carcinoma (HGSC). Smaller studies have revealed unfavorable associations for CCNE1 amplification and CCNE1 overexpression with survival, but to date no large-scale, histotype-specific validation has been performed. The hypothesis was that high-level amplification of CCNE1 and CCNE1 overexpression, as well as a combination of the two, are linked to shorter overall survival in HGSC. METHODS: Within the Ovarian Tumor Tissue Analysis consortium, amplification status and protein level in 3029 HGSC cases and mRNA expression in 2419 samples were investigated. RESULTS: High-level amplification (>8 copies by chromogenic in situ hybridization) was found in 8.6% of HGSC and overexpression (>60% with at least 5% demonstrating strong intensity by immunohistochemistry) was found in 22.4%. CCNE1 high-level amplification and overexpression both were linked to shorter overall survival in multivariate survival analysis adjusted for age and stage, with hazard stratification by study (hazard ratio [HR], 1.26; 95% CI, 1.08-1.47, p = .034, and HR, 1.18; 95% CI, 1.05-1.32, p = .015, respectively). This was also true for cases with combined high-level amplification/overexpression (HR, 1.26; 95% CI, 1.09-1.47, p = .033). CCNE1 mRNA expression was not associated with overall survival (HR, 1.00 per 1-SD increase; 95% CI, 0.94-1.06; p = .58). CCNE1 high-level amplification is mutually exclusive with the presence of germline BRCA1/2 pathogenic variants and shows an inverse association to RB1 loss. CONCLUSION: This study provides large-scale validation that CCNE1 high-level amplification is associated with shorter survival, supporting its utility as a prognostic biomarker in HGSC.

Asunto(s)

Carcinoma , Cistadenocarcinoma Seroso , Neoplasias Ováricas , Femenino , Humanos , Neoplasias Ováricas/patología , Factores de Transcripción/genética , ARN Mensajero , Cistadenocarcinoma Seroso/genética , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/uso terapéutico , Ciclina E/genética

RESUMEN

Cyclin E1 (CCNE1) is a protein-coding gene that belongs to the Cyclin family of genes which controls the G1/S phase transition of the cell cycle. Previously, its abnormal expression pattern has been examined and found to be correlated with ovarian and breast cancer progression. Herein, we exploited a bioinformatics and database mining strategy to unveil the therapeutic and prognostic significance of CCNE1 gene expression in Lung Adenocarcinoma (LUAD) and Lung Squamous Cell Carcinoma (LUSC). CCNE1 gene was reported to be highly expressed in LUAD and LUSC tissues. Its promoter and coding sequences were reported to be aberrantly methylated in LUAD and LUSC tissues than in normal tissues. Moreover, around 12 somatic mutations (frequency: 0.7%) were recorded in the CCNE1 coding region from different studies involving LUAD and LUSC patients' whole genome sequences. The CCNE1 gene expression was also correlated with LUAD and LUSC patients' overall and disease-specific survival. Immune infiltration analysis revealed the association between CCNE1 gene expression and the abundance of numerous immune cells (i.e., T cells and B Cells) infiltration in LUAD and LUSC patients. Two previously known genes involved in oncogenic processes i.e., CDC45 and PDCD5 were identified as the most highly co-expressed genes of CCNE1 in LUAD and LUSC tissues. Altogether, the CCNE1 gene and its transcriptional and translational products may serve as a prognostic or therapeutic target in the diagnosis and treatment of LUAD and LUSC patients. The scientific findings of this study should assist in translating CCNE1 into clinical practice for lung cancer diagnosis and treatment.

RESUMEN

MiR-181 expression levels increased in hepatocellular carcinoma (HCC) compared to non-cancerous tissues. MiR-181 has been widely reported as a possible driver of tumourigenesis but also acts as a tumour suppressor. In addition, the miR-181 family regulates the development and function of immune and vascular cells, which play vital roles in the progression of tumours. More complicatedly, many genes have been identified as miR-181 targets to mediate the effects of miR-181. However, the role of miR-181 in the development of primary tumours remains largely unexplored. We aimed to examine the function of miR-181 and its vital mediators in the progression of diethylnitrosamine-induced primary liver cancers in mice. The size of liver tumours was significantly reduced by 90% in global (GKO) or liver-specific (LKO) 181ab1 knockout mice but not in hematopoietic and endothelial lineage-specific knockout mice, compared to WT mice. In addition, the number of tumours was significantly reduced by 50% in GKO mice. Whole-genome RNA-seq analysis and immunohistochemistry showed that epithelial-mesenchymal transition was partially reversed in GKO tumours compared to WT tumours. The expression of CBX7, a confirmed miR-181 target, was up-regulated in GKO compared to WT tumours. Stable CBX7 expression was achieved with an AAV/Transposase Hybrid-Vector System and up-regulated CBX7 expression inhibited liver tumour progression in WT mice. Hepatic CBX7 deletion restored the progression of LKO liver tumours. MiR-181a expression was the lowest and CBX7 expression the highest in iClust2 and 3 subclasses of human HCC compared to iClust1. Gene expression profiles of GKO tumours overlapped with low-proliferative peri-portal-type HCCs. Liver-specific loss of miR-181ab1 inhibited primary liver tumour progression via up-regulating CBX7 expression, but tumour induction requires both hepatic and non-hepatic miR-181. Also, miR-181ab1-deficient liver tumours may resemble low-proliferative periportal-type human HCC. miR-181 was increased with liver tumour growth. More miR-181, darker colour and higher shape. CBX7 was very low in pericentral hepatocytes, increased in early liver tumours, but reduced in advanced liver tumours. Its levels were maintained in miR-181 KO liver tumours. In tumours (T), brown (darker is more) represents miR-181, the blue circle (thicker is more) represents CBX7.

Asunto(s)

Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Animales , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Complejo Represivo Polycomb 1/genética , Complejo Represivo Polycomb 1/metabolismo , Regulación hacia Arriba/genética

RESUMEN

Basal-like breast cancer (BLBC) has a greater overlap in molecular features with high-grade serous ovarian cancer (HGSOC) than with other breast cancer subtypes. Similarities include BRCA1 mutation, high frequency of TP53 mutation, and amplification of CCNE1 (encoding the cyclin E1 protein) in 6-34% of cases, and these features can be used to group patients for targeted therapies in clinical trials. In HGSOC, we previously reported two subsets with high levels of cyclin E1: those in which CCNE1 is amplified, have intact homologous recombination (HR), and very poor prognosis; and a CCNE1 non-amplified subset, with more prevalent HR defects. Here, we investigate whether similar subsets are identifiable in BLBC that may allow alignment of patient grouping in clinical trials of agents targeting cyclin E1 overexpression. We examined cyclin E1 protein and CCNE1 amplification in a cohort of 76 BLBCs and validated the findings in additional breast cancer datasets. Compared to HGSOC, CCNE1 amplified BLBC had a lower level of amplification (3.5 versus 5.2 copies) and lower relative cyclin E1 protein, a lack of correlation of amplification with expression, and no association with polyploidy. BLBC with elevated cyclin E1 protein also had prevalent HR defects, and high-level expression of the cyclin E1 deubiquitinase ubiquitin-specific protease 28 (USP28). Using a meta-analysis across multiple studies, we determined that cyclin E1 protein overexpression but not amplification is prognostic in BLBC, while both cyclin E1 overexpression and amplification are prognostic in HGSOC. Overall CCNE1 gene amplification is not equivalent between BLBC and HGSOC. However, high cyclin E1 protein expression can co-occur with HR defects in both BLBC and HGSOC, and is associated with poor prognosis in BLBC.

Asunto(s)

Neoplasias de la Mama , Ciclina E , Proteínas Oncogénicas , Neoplasias Ováricas , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/patología , Ciclina E/genética , Ciclina E/metabolismo , Femenino , Amplificación de Genes , Humanos , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Pronóstico , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo

RESUMEN

Background: Clear cell renal cell carcinoma (ccRCC) is a cell metabolic disease with high metastasis rate and poor prognosis. Our previous studies demonstrate that glucose-6-phosphate dehydrogenase (G6PD), the first and rate-limiting enzyme of the pentose phosphate pathway, is highly expressed in ccRCC and predicts poor outcomes of ccRCC patients. The aims of this study were to confirm the oncogenic role of G6PD in ccRCC and unravels novel mechanisms involving Cyclin E1 and MMP9 in G6PD-mediated ccRCC progression. Methods: Real-time RT-PCR, Western blot and immunohistochemistry were used to determine the expression patterns of G6PD, Cyclin E1 and MMP9 in ccRCC. TCGA dataset mining was used to identify Cyclin E1 and MMP9 correlations with G6PD expression, relationships between clinicopathological characteristics of ccRCC and the genes of interest, as well as the prognosis of ccRCC patients. The role of G6PD in ccRCC progression and the regulatory effect of G6PD on Cyclin E1 and MMP9 expression were investigated by using a series of cytological function assays in vitro. To verify this mechanism in vivo, xenografted mice models were established. Results: G6PD, Cyclin E1 and MMP9 were overexpressed and positively correlated in ccRCC, and they were associated with poor prognosis of ccRCC patients. Moreover, G6PD changed cell cycle dynamics, facilitated cells proliferation, promoted migration in vitro, and enhanced ccRCC development in vivo, more likely through enhancing Cyclin E1 and MMP9 expression. Conclusion: These findings present G6PD, Cyclin E1 and MMP9, which contribute to ccRCC progression, as novel biomarkers and potential therapeutic targets for ccRCC treatment.

Asunto(s)

Carcinoma de Células Renales/genética , Ciclina E/genética , Regulación Neoplásica de la Expresión Génica , Glucosafosfato Deshidrogenasa/fisiología , Neoplasias Renales/genética , Metaloproteinasa 9 de la Matriz/genética , Proteínas Oncogénicas/genética , Regulación hacia Arriba , Animales , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Ciclina E/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Humanos , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Estadificación de Neoplasias , Proteínas Oncogénicas/metabolismo

RESUMEN

Clear cell renal cell carcinoma (ccRCC) has been proved to be a metabolic disease with high

RESUMEN

Emerging evidence has shown that microRNA (miR)­497 serves pivotal roles in tumorigenesis, cancer progression, metastasis and chemotherapy resistance in several types of cancer. In the present study, the expression and biological functions of miR­497 host gene (MIR497HG) were investigated in glioma tissue. The expression levels of miR­497 and MIR497HG were measured in glioma, adjacent non­cancerous and normal brain tissue and their association with the prognosis of patients with glioma were analyzed. The biological roles of miR­497 and MIR497HG were investigated in glioma cell lines. In addition, bioinformatics analysis, luciferase reporter assay and functional experiments were performed to identify and validate the downstream targets of miR­497 or MIR497HG. The expression levels of miR­497 and MIR497HG were downregulated in glioma tissue and cell lines compared with those in adjacent non­cancerous and normal brain tissue and normal human cortical neuron cell line. Patients with low miR­497 or MIR497HG expression levels exhibited a poor prognostic outcome. In addition, forced overexpression of miR­497 or MIR497HG significantly inhibited the proliferation and cell cycle progression of glioma cell lines. Furthermore, the results indicated that miR­497 and MIR497HG exerted their biological functions by direct targeting of cyclin E1 and miR­588/tumor suppressor candidate 1. In summary, the data indicated that miR­497 and MIR497HG served as tumor suppressors and may be used as potential therapeutic targets and prognostic biomarkers in glioma.

Asunto(s)

Proliferación Celular/genética , Ciclina E/genética , Glioma/genética , MicroARNs/genética , Proteínas Oncogénicas/genética , Proteínas Supresoras de Tumor/genética , Adulto , Animales , Neoplasias Encefálicas/genética , Carcinogénesis/genética , Ciclo Celular/genética , Línea Celular Tumoral , Modelos Animales de Enfermedad , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad

RESUMEN

The relative benefit of bevacizumab in ovarian cancer (OC) patients is greater the more the disease becomes platinum-resistant. Among other mechanisms of action, antiangiogenic agents may induce homologous recombination deficiency. Cyclin E1 (CCNE1) overexpression is a proposed marker of platinum resistance and is mutually exclusive with deficiency in homologous recombination. In this study, we evaluated the predictive value of CCNE1 expression with regard to the efficacy of bevacizumab. We retrospectively evaluated data from patients with platinum-sensitive recurrent OC who were treated with chemotherapy (CT) plus bevacizumab (Bev group) or CT alone (CT group) at a tertiary cancer centre from 2005 to 2017. The two groups were paired according to histology, platinum-free interval (PFI) and number of previous treatment lines. Progression-free survival (PFS) was compared between groups by log rank test and Cox regression. A total of 124 patients were included, with 62 in each group. The groups were well balanced regarding histology, PFI and number of previous treatment lines. Median PFS (mPFS) was 19.5 months for the Bev group versus 16.0 months for CT group (p = 0.150). By multivariate analysis, the HR for PFS was 2.25 (95% CI: 1.10-4.60) for CCNE1 overexpression. The benefit of bevacizumab was larger in the subgroups of patients with PFI 6-12 months (mPFS 18.6 versus 10.4 months, p = 0.002) and CCNE1 overexpression (mPFS 16.3 versus 7.0 months, p = 0.010). In conclusion, CCNE1 overexpression and PFI may suggest which patients will receive the greatest benefit from bevacizumab. These data, if confirmed by other studies, could help better select patients for antiangiogenic therapy.

RESUMEN

Tazarotene-induced gene 1 (TIG1) is considered to be a tumor suppressor gene that is highly expressed in normal or well-differentiated colon tissues, while downregulation of TIG1 expression occurs in poorly differentiated colorectal cancer (CRC) tissues. However, it is still unclear how TIG1 regulates the tumorigenesis of CRC. Polo-like kinases (Plks) are believed to play an important role in regulating the cell cycle. The performance of PLK2 in CRC is negatively correlated with the differentiation status of CRC tissues. Here, we found that PLK2 can induce the growth of CRC cells and that TIG1 can prevent PLK2 from promoting the proliferation of CRC cells. We also found that the expression of PLK2 in CRC cells was associated with low levels of Fbxw7 protein and increased expression of cyclin E1. When TIG1 was coexpressed with PLK2, the changes in Fbxw7/cyclin E1 levels induced by PLK2 were reversed. In contrast, silencing TIG1 promoted the proliferation of CRC, and when PLK2 was also silenced, the proliferation of CRC cells induced by TIG1 silencing was significantly inhibited. The above research results suggest that TIG1 can regulate the tumorigenesis of CRC by regulating the activity of PLK2.

Asunto(s)

Neoplasias Colorrectales/genética , Proteínas de la Membrana/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , División Celular/genética , Proliferación Celular/genética , Neoplasias Colorrectales/metabolismo , Ciclina E/genética , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Silenciador del Gen/fisiología , Células HCT116 , Humanos , Proteínas de la Membrana/metabolismo , Proteínas Oncogénicas/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Quinasa Tipo Polo 1

RESUMEN

BACKGROUND: Ovarian clear cell carcinoma (OCCC) is resistant to platinum chemotherapy and is characterized by poor prognosis. Today, the use of poly (ADP-ribose) polymerase (PARP) inhibitor, which is based on synthetic lethality strategy and characterized by cancer selectivity, is widely used for new types of molecular-targeted treatment of relapsed platinum-sensitive ovarian cancer. However, it is less effective against OCCC. METHODS: We conducted siRNA screening to identify synthetic lethal candidates for the ARID1A mutation; as a result, we identified Cyclin-E1 (CCNE1) as a potential target that affects cell viability. To further clarify the effects of CCNE1, human OCCC cell lines, namely TOV-21G and KOC7c (ARID1A mutant lines), and RMG-I and ES2 (ARID1A wild type lines) were transfected with siRNA targeting CCNE1 or a control vector. RESULTS: Loss of CCNE1 reduced proliferation of the TOV-21G and KOC7c cells but not of the RMG-I and ES2 cells. Furthermore, in vivo interference of CCNE1 effectively inhibited tumor cell proliferation in a xenograft mouse model. CONCLUSION: This study showed for the first time that CCNE1 is a synthetic lethal target gene to ARID1A-mutated OCCC. Targeting this gene may represent a putative, novel, anticancer strategy in OCCC treatment.

Asunto(s)

Adenocarcinoma de Células Claras/genética , Ciclina E/genética , Proteínas de Unión al ADN/genética , Proteínas Oncogénicas/genética , Neoplasias Ováricas/genética , Mutaciones Letales Sintéticas , Factores de Transcripción/genética , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/patología , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cisplatino/farmacología , Ciclina E/antagonistas & inhibidores , Ciclina E/metabolismo , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ratones Desnudos , Terapia Molecular Dirigida , Proteínas Oncogénicas/antagonistas & inhibidores , Proteínas Oncogénicas/metabolismo , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto

RESUMEN

Krüppel-like factor 5 (KLF5) is involved in various cellular processes, such as cell proliferation and survival. KLF5 has been implicated in cancer pathology. The aim of the present study was to investigate the expression levels and function of KLF5 in endometrial cancer. A total of 30 patients, including 12 patients with endometrial cancer and 18 with benign gynecological diseases (controls), were enrolled at Tokyo Medical University (Tokyo, Japan) between March 2017 and May 2018. Endometrial cancer and control endometrium tissues were collected, and the expression levels of KLF5 were determined using reverse transcription-quantitative PCR, western blotting and immunohistochemistry. For the functional analyses of KLF5 in endometrial cancer, the present study employed a loss-of-function strategy in the human endometrial cancer cell lines in vitro. Ishikawa and HEC1 cells were transduced with lentiviral constructs expressing shRNAs targeting KLF5. MTT and TUNEL assays were performed in cells after knockdown to analyze the role of KLF5 in cell proliferation and survival. The results revealed that the mRNA and protein expression levels of KLF5 were increased in endometrial cancer tissues. In vitro analyses demonstrated that depletion of KLF5 inhibited cell proliferation and decreased the expression levels of cyclin E1. However, silencing KLF5 did not induce cell death. Overall, these results indicated that KLF5 may be crucial in the tumorigenesis of endometrial cancer and has potential as a therapeutic target.

RESUMEN

BACKGROUND: Checkpoint kinase 1 (CHK1) has dual roles in both the DNA damage response and in the innate immune response to genotoxic stress. The combination of CHK1 inhibition and immune checkpoint blockade has the potential to enhance anti-tumoral T-cell activation. METHODS: This was an open-label phase 1 study evaluating the CHK1 inhibitor prexasertib and the anti-PD-L1 antibody LY3300054. After a lead-in of LY3300054 (Arm A), prexasertib (Arm B) or the combination (Arm C), both agents were administered intravenously at their respective recommended phase 2 doses (RP2Ds) on days 1 and 15 of a 28-day cycle. Flow cytometry of peripheral blood was performed before and during treatment to analyze effects on immune cell populations, with a focus on T cell subsets and activation. Plasma cytokines and chemokines were analyzed using the Luminex platform. RESULTS: Among seventeen patients enrolled, the combination was tolerable at the monotherapy RP2Ds, 105 mg/m2 prexasertib and 700 mg LY3300054. Dose-limiting toxicities included one episode each of febrile neutropenia (Arm C) and grade 4 neutropenia lasting > 5 days (Arm B). One patient had immune-related AST/ALT elevation after 12 cycles. Three patients with CCNE1-amplified, high-grade serous ovarian cancer (HGSOC) achieved partial response (PR), 2 lasting > 12 months; a fourth such patient maintained stable disease > 12 months. Analysis of peripheral blood demonstrated evidence of CD8 + T-cell activation in response to treatment. CONCLUSIONS: Prexasertib in combination with PD-L1 blockade was tolerable and demonstrated preliminary activity in CCNE1-amplified HGSOC with evidence of cytotoxic T-cell activation in patient blood samples. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03495323. Registered April 12, 2018.

Asunto(s)

Antineoplásicos/uso terapéutico , Cistadenocarcinoma Seroso/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Pirazinas/uso terapéutico , Pirazoles/uso terapéutico , Adulto , Anciano , Antineoplásicos/farmacología , Cistadenocarcinoma Seroso/patología , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/patología , Pirazinas/farmacología , Pirazoles/farmacología

RESUMEN

The constitutive androstane receptor (CAR, NR3I1) belongs to nuclear receptor superfamily. It was reported that CAR agonist TCPOBOP induces hepatomegaly but the underlying mechanism remains largely unknown. Yes-associated protein (YAP) is a potent regulator of organ size. The aim of this study is to explore the role of YAP in CAR activation-induced hepatomegaly and liver regeneration. TCPOBOP-induced CAR activation on hepatomegaly and liver regeneration was evaluated in wild-type (WT) mice, liver-specific YAP-deficient mice, and partial hepatectomy (PHx) mice. The results demonstrate that TCPOBOP can increase the liver-to-body weight ratio in wild-type mice and PHx mice. Hepatocytes enlargement around central vein (CV) area was observed, meanwhile hepatocytes proliferation was promoted as evidenced by the increased number of KI67+ cells around portal vein (PV) area. The protein levels of YAP and its downstream targets were upregulated in TCPOBOP-treated mice and YAP translocation can be induced by CAR activation. Co-immunoprecipitation results suggested a potential protein-protein interaction of CAR and YAP. However, CAR activation-induced hepatomegaly can still be observed in liver-specific YAP-deficient (Yap -/-) mice. In summary, CAR activation promotes hepatomegaly and liver regeneration partially by inducing YAP translocation and interaction with YAP signaling pathway, which provides new insights to further understand the physiological functions of CAR.