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43 result(s) for "Chiappetta, Gennaro"
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Development and validation of a microRNA-based signature (MiROvaR) to predict early relapse or progression of epithelial ovarian cancer: a cohort study
Risk of relapse or progression remains high in the treatment of most patients with epithelial ovarian cancer, and development of a molecular predictor could be a valuable tool for stratification of patients by risk. We aimed to develop a microRNA (miRNA)-based molecular classifier that can predict risk of progression or relapse in patients with epithelial ovarian cancer. We analysed miRNA expression profiles in three cohorts of samples collected at diagnosis. We used 179 samples from a Multicenter Italian Trial in Ovarian cancer trial (cohort OC179) to develop the model and 263 samples from two cancer centres (cohort OC263) and 452 samples from The Cancer Genome Atlas epithelial ovarian cancer series (cohort OC452) to validate the model. The primary clinical endpoint was progression-free survival, and we adapted a semi-supervised prediction method to the miRNA expression profile of OC179 to identify miRNAs that predict risk of progression. We assessed the independent prognostic role of the model using multivariable analysis with a Cox regression model. We identified 35 miRNAs that predicted risk of progression or relapse and used them to create a prognostic model, the 35-miRNA-based predictor of Risk of Ovarian Cancer Relapse or progression (MiROvaR). MiROvaR was able to classify patients in OC179 into a high-risk group (89 patients; median progression-free survival 18 months [95% CI 15–22]) and a low-risk group (90 patients; median progression-free survival 38 months [24–not estimable]; hazard ratio [HR] 1·85 [1·29–2·64], p=0·00082). MiROvaR was a significant predictor of progression in the two validation sets (OC263 HR 3·16, 95% CI 2·33–4·29, p<0·0001; OC452 HR 1·39, 95% CI 1·11–1·74, p=0·0047) and maintained its independent prognostic effect when adjusted for relevant clinical covariates using multivariable analyses (OC179: adjusted HR 1·48, 95% CI 1·03–2·13, p=0·036; OC263: adjusted HR 3·09 [2·24–4·28], p<0·0001; and OC452: HR 1·41 [1·11–1·79], p=0·0047). MiROvaR is a potential predictor of epithelial ovarian cancer progression and has prognostic value independent of relevant clinical covariates. MiROvaR warrants further investigation for the development of a clinical-grade prognostic assay. AIRC and CARIPLO Foundation.
microRNA signature defines chemoresistance in ovarian cancer through modulation of angiogenesis
Epithelial ovarian cancer is the most lethal gynecologic malignancy; it is highly aggressive and causes almost 125,000 deaths yearly. Despite advances in detection and cytotoxic therapies, a low percentage of patients with advanced stage disease survive 5 y after the initial diagnosis. The high mortality of this disease is mainly caused by resistance to the available therapies. Here, we profiled microRNA (miR) expression in serous epithelial ovarian carcinomas to assess the possibility of a miR signature associated with chemoresistance. We analyzed tumor samples from 198 patients (86 patients as a training set and 112 patients as a validation set) for human miRs. A signature of 23 miRs associated with chemoresistance was generated by array analysis in the training set. Quantitative RT-PCR in the validation set confirmed that three miRs (miR-484, -642, and -217) were able to predict chemoresistance of these tumors. Additional analysis of miR-484 revealed that the sensitive phenotype is caused by a modulation of tumor vasculature through the regulation of the VEGFB and VEGFR2 pathways. We present compelling evidence that three miRs can classify the response to chemotherapy of ovarian cancer patients in a large multicenter cohort and that one of these three miRs is involved in the control of tumor angiogenesis, indicating an option in the treatment of these patients. Our results suggest, in fact, that blockage of VEGF through the use of an anti-VEGFA antibody may not be sufficient to improve survival in ovarian cancer patients unless VEGFB signaling is also blocked.
CDK6 protects epithelial ovarian cancer from platinum‐induced death via FOXO3 regulation
Epithelial ovarian cancer (EOC) is an infrequent but highly lethal disease, almost invariably treated with platinum‐based therapies. Improving the response to platinum represents a great challenge, since it could significantly impact on patient survival. Here, we report that silencing or pharmacological inhibition of CDK6 increases EOC cell sensitivity to platinum. We observed that, upon platinum treatment, CDK6 phosphorylated and stabilized the transcription factor FOXO3, eventually inducing ATR transcription. Blockage of this pathway resulted in EOC cell death, due to altered DNA damage response accompanied by increased apoptosis. These observations were recapitulated in EOC cell lines in vitro , in xenografts in vivo , and in primary tumor cells derived from platinum‐treated patients. Consistently, high CDK6 and FOXO3 expression levels in primary EOC predict poor patient survival. Our data suggest that CDK6 represents an actionable target that can be exploited to improve platinum efficacy in EOC patients. As CDK4/6 inhibitors are successfully used in cancer patients, our findings can be immediately transferred to the clinic to improve the outcome of EOC patients. Synopsis In epithelial ovarian cancer cells, platinum favours binding and phosphorylation of FOXO3 by the CDK6/cyclin D3 complex. FOXO3 is thus stabilized and binds the ATR promoter thereby inducing its transcription and preventing platinum‐induced cell death. CDK6 in complex with cyclin D3 participates in the control of DNA damage response. CDK6 binds and phosphorylates FOXO3 on serine 325 to control ATR expression. High CDK6 expression predicts poor survival of EOC patients. A combination of platinum‐based chemotherapy with pharmacological CDK6 inhibition might be a new therapeutic option for EOC patients. Graphical Abstract In epithelial ovarian cancer cells, platinum favours binding and phosphorylation of FOXO3 by the CDK6/cyclin D3 complex. FOXO3 is thus stabilized and binds the ATR promoter thereby inducing its transcription and preventing platinum‐induced cell death.
neutrophil gelatinase-associated lipocalin (NGAL), a NF-κB-regulated gene, is a survival factor for thyroid neoplastic cells
NF-κB is constitutively activated in primary human thyroid tumors, particularly in those of anaplastic type. The inhibition of NF-κB activity in the human anaplastic thyroid carcinoma cell line, FRO, leads to an increased susceptibility to chemotherapeutic drug-induced apoptosis and to the blockage of their ability to form tumors in nude mice. To identify NF-κB target genes involved in thyroid cancer, we analyzed the secretome of conditioned media from parental and NF-κB-null FRO cells. Proteomic analysis revealed that the neutrophil gelatinase-associated lipocalin (NGAL), a protein involved in inflammatory and immune responses, is secreted by FRO cells whereas its expression is strongly reduced in the NF-κB-null FRO cells. NGAL is highly expressed in human thyroid carcinomas, and knocking down its expression blocks the ability of FRO cells to grow in soft agar and form tumors in nude mice. These effects are reverted by the addition of either recombinant NGAL or FRO conditioned medium. In addition, we show that the prosurvival activity of NGAL is mediated by its ability to bind and transport iron inside the cells. Our data suggest that NF-κB contributes to thyroid tumor cell survival by controlling iron uptake via NGAL.
Galectin-3-expression analysis in the surgical selection of follicular thyroid nodules with indeterminate fine-needle aspiration cytology: a prospective multicentre study
In the USA, about 30 200 well-differentiated thyroid carcinomas were diagnosed in 2007, but the prevalence of thyroid nodules is much higher (about 5% of the adult population). Unfortunately, the preoperative characterisation of follicular thyroid nodules is still a challenge, and many benign lesions, which remain indeterminate after fine-needle aspiration (FNA) cytology are referred to surgery. About 85% of these thyroid nodules are classified as benign at final histology. We aimed to assess the diagnostic effect of galectin-3 expression analysis in distinguishing preoperatively benign from malignant follicular thyroid nodules when FNA findings were indeterminate. 544 patients were enrolled between June 1, 2003, and Aug 30, 2006. We used a purified monoclonal antibody to galectin-3, a biotin-free immunocytohistochemical assay, and a morphological and phenotypic analysis of FNA-derived cell-block preparations. Galectin-3-expression analysis was applied preoperatively on 465 follicular thyroid proliferations that were candidates for surgery, and its diagnostic accuracy was compared with the final histology. 31 patients were excluded because they had small galectin-3-negative thyroid nodules; we did not have data for 47 patients; and one patient with an oncocytic nodule was excluded. 331 (71%) of the assessable 465 preoperative thyroid FNA samples did not express galectin-3. 280 (85%) of these galectin-3-negative lesions were classified as benign at final histology. Galectin-3 expression was detected, instead, in 134 of 465 (29%) thyroid proliferations, 101 (75%) of which were confirmed as malignant. The overall sensitivity of the galectin-3 test was 78% (95% CI 74–82) and specificity was 93% (90–95). Estimated positive predictive value was 82% (79–86) and negative predictive value was 91% (88–93). 381 (88%) of 432 patients with follicular thyroid nodules who were referred for thyroidectomy were correctly classified preoperatively by use of the galectin-3 test. However, 29 (22%) of 130 cancers were missed by the galectin-3 method. Our findings show that if the option of surgery was based theoretically on galectin-3 expression alone, only 134 thyroid operations would have been done in 465 patients; therefore a large proportion (71%) of unnecessary thyroid surgical procedures could be avoided, although a number of galectin-3-negative cancers could be potentially missed. The galectin-3 test proposed here does not replace conventional FNA cytology, but represents a complementary diagnostic method for those follicular nodules that remain indeterminate. Compagnia di San Paolo, Turin, Italy, and Italian Association for Cancer Research (AIRC), Rome, Italy.
IKKγ protein is a target of BAG3 regulatory activity in human tumor growth
BAG3, a member of the BAG family of heat shock protein (HSP) 70 cochaperones, is expressed in response to stressful stimuli in a number of normal cell types and constitutively in a variety of tumors, including pancreas carcinomas, lymphocytic and myeloblastic leukemias, and thyroid carcinomas. Down-regulation of BAG3 results in cell death, but the underlying molecular mechanisms are still elusive. Here, we investigated the molecular mechanism of BAG3-dependent survival in human osteosarcoma (SAOS-2) and melanoma (M14) cells. We show that bag3 overexpression in tumors promotes survival through the NF-κB pathway. Indeed, we demonstrate that BAG3 alters the interaction between HSP70 and IKKγ, increasing availability of IKKγ and protecting it from proteasome-dependent degradation; this, in turn, results in increased NF-κB activity and survival. These results identify bag3 as a potential target for anticancer therapies in those tumors in which this gene is constitutively expressed. As a proof of principle, we show that treatment of a mouse xenograft tumor model with bag3siRNA-adenovirus that down-regulates bag3 results in reduced tumor growth and increased animal survival.
The Epithelial-to-Mesenchymal Transition in Breast Cancer: Focus on Basal-Like Carcinomas
Breast cancer is a heterogeneous disease that is characterized by a high grade of cell plasticity arising from the contribution of a diverse range of factors. When combined, these factors allow a cancer cell to transition from an epithelial to a mesenchymal state through a process of dedifferentiation that confers stem-like features, including chemoresistance, as well as the capacity to migrate and invade. Understanding the complex events that lead to the acquisition of a mesenchymal phenotype will therefore help to design new therapies against metastatic breast cancer. Here, we recapitulate the main endogenous molecular signals involved in this process, and their cross-talk with paracrine factors. These signals and cross-talk include the extracellular matrix; the secretome of cancer-associated fibroblasts, macrophages, cancer stem cells, and cancer cells; and exosomes with their cargo of miRNAs. Finally, we highlight some of the more promising therapeutic perspectives based on counteracting the epithelial-to-mesenchymal transition in breast cancer cells.
YY1 overexpression is associated with poor prognosis and metastasis-free survival in patients suffering osteosarcoma
Background The polycomb transcription factor Yin Yang 1 (YY1) overexpression can be causally implicated in experimental tumor growth and metastasization. To date, there is no clinical evidence of YY1 involvement in outcome of patients with osteosarcoma. Prognosis of osteosarcoma is still severe and only few patients survive beyond five years. We performed a prospective immunohistochemistry analysis to correlate YY1 immunostaining with metastatic development and survival in a selected homogeneous group of patients with osteosarcoma. Methods We studied 41 patients suffering from osteosarcoma (stage II-IVa). Multivariate analysis was performed using Cox proportional hazard regression to evaluate the correlation between YY1 expression and both metastasis development and mortality. Results YY1 protein is not usually present in normal bone; in contrast, a high number of patients (61%) showed a high score of YY1 positive cells (51-100%) and 39% had a low score (10-50% positive cells). No statistical difference was found in histology, anatomic sites, or response to chemotherapy between the two degrees of YY1 expression. Cox regression analysis demonstrated that the highest score of YY1 expression was predictive of both low metastasis-free survival (HR = 4.690, 95%CI = 1.079-20.396; p = 0.039) and poor overall survival (HR = 8.353, 95%CI = 1.863-37.451 p = 0.006) regardless of the effects of covariates such as age, gender, histology and chemonecrosis. Conclusion Overexpression of YY1 in primary site of osteosarcoma is associated with the occurrence of metastasis and poor clinical outcome.
Adenovirus-Mediated Suppression of HMGI(Y) Protein Synthesis as Potential Therapy of Human Malignant Neoplasias
High mobility group I (HMGI) proteins are overexpressed in several human malignant tumors. We previously demonstrated that inhibition of HMGI synthesis prevents thyroid cell transformation. Here, we report that an adenovirus carrying the HMGI(Y) gene in an antisense orientation (Ad-Yas) induced programmed cell death of two human thyroid anaplastic carcinoma cell lines (ARO and FB-1), but not normal thyroid cells. The Ad-Yas virus led to death of lung, colon, and breast carcinoma cells. A control adenovirus carrying the lacZ gene did not inhibit the growth of either normal or neoplastic cells. Ad-Yas treatment of tumors induced in athymic mice by ARO cells caused a drastic reduction in tumor size. Therefore, suppression of HMGI(Y) protein synthesis by an HMGI(Y) antisense adenoviral vector may be a useful treatment strategy in a variety of human malignant neoplasias, in which HMGI(Y) gene overexpression is a general event.
PTEN expression is reduced in a subset of sporadic thyroid carcinomas: evidence that PTEN-growth suppressing activity in thyroid cancer cells is mediated by p27kip1
The dual-specificity phosphatase PTEN/MMAC1/TEP1 has recently been identified as the tumor suppressor gene most frequently mutated and/or deleted in human tumors. Germline mutations of PTEN give rise to Cowden Disease (CD), an autosomal dominantly-inherited cancer syndrome which predisposes to increased risk of developing breast and thyroid tumors. However, PTEN mutations have rarely been detected in sporadic thyroid carcinomas. In this study, we confirm that PTEN mutations in sporadic thyroid cancer are infrequent as we found one point mutation and one heterozygous deletion of PTEN gene in 26 tumors and eight cell lines screened. However, we report that PTEN expression is reduced both at the mRNA and at the protein level - in five out of eight tumor-derived cell lines and in 24 out of 61 primary tumors. In most cases, decreased PTEN expression is correlated with increased phosphorylation of the PTEN-regulated protein kinase Akt/PKB. Moreover, we demonstrate that PTEN may act as a suppressor of thyroid cancerogenesis as the constitutive re-expression of PTEN into two different thyroid tumor cell lines markedly inhibits cell growth. PTEN-dependent inhibition of BrdU incorporation is accompanied by enhanced expression of the cyclin-dependent kinase inhibitor p27kip1 and can be overcome by simultaneous co-transfection of an excess p27kip1 antisense plasmid. Accordingly, in a subset of thyroid primary carcinomas and tumor-derived cell lines, a striking correlation between PTEN expression and the level of p27kip1 protein was observed. In conclusion, our findings demonstrate that inactivation of PTEN may play a role in the development of sporadic thyroid carcinomas and that one key target of PTEN suppressor activity is represented by the cyclin-dependent kinase inhibitor p27kip1.