Luca Clivio

Association between miR-200c and the survival of patients with stage I epithelial ovarian cancer: a retrospective study of two independent tumour tissue collections.

BACKGROUND International Federation of Gynecology and Obstetrics stage I epithelial ovarian cancer (EOC) has a significantly better prognosis than stage III/IV EOC, with about 80% of patients surviving at 5 years (compared with about 20% of those with stage III/IV EOC). However, 20% of patients with stage I EOC relapse within 5 years. It is therefore crucial that the biological properties of stage I EOCs are further elucidated. MicroRNAs (miRNAs) have shown diagnostic and prognostic potential in stage III and IV EOCs, but the small number of patients diagnosed with stage I EOC has so far prevented an investigation of its molecular features. We profiled miRNA expression in stage I EOC tumours to assess whether there is a miRNA signature associated with overall and progression-free survival (PFS) in stage I EOC. METHODS We analysed tumour samples from 144 patients (29 of whom relapsed) with stage I EOC gathered from two independent tumour tissue collections (A and B), both with a median follow-up of 9 years. 89 samples from tumour tissue collection A were stratified into a training set (51 samples, 15 of which were from patients who relapsed) for miRNA signature generation, and into a validation set (38 samples, seven of which were from patients who relapsed) for signature validation. Tumour tissue collection B (55 samples, seven of which were from patients who relapsed) was used as an independent test set. The Cox proportional hazards model and the log-rank test were used to assess the correlation of quantitative reverse transcription PCR (qRT-PCR)-validated miRNAs with overall survival and PFS. FINDINGS A signature of 34 miRNAs associated with survival was generated by microarray analysis in the training set. In both the training set and validation set, qRT-PCR analysis confirmed that 11 miRNAs (miR-214, miR-199a-3p, miR-199a-5p, miR-145, miR-200b, miR-30a, miR-30a*, miR-30d, miR-200c, miR-20a, and miR-143) were expressed differently in relapsers compared with non-relapsers. Three of these miRNAs (miR-200c, miR-199a-3p, miR-199a-5p) were associated with PFS, overall survival, or both in multivariate analysis. qRT-PCR analysis in the test set confirmed the downregulation of miR-200c in relapsers compared with non-relapsers, but not the upregulation of miR-199a-3p and miR-199a-5p. Multivariate analysis confirmed that downregulation of miR-200c in the test set was associated with overall survival (HR 0·094, 95% CI 0·012-0·766, p=0·0272) and PFS (0·035, 0·004-0·311; p=0·0026), independent of clinical covariates. INTERPRETATION miR-200c has potential as a predictor of survival, and is a biomarker of relapse, in stage I EOC. FUNDING Nerina and Mario Mattioli Foundation, Cariplo Foundation (Grant Number 2010-0744), and the Italian Association for Cancer Research.

Resistance to platinum-based chemotherapy is associated with epithelial to mesenchymal transition in epithelial ovarian cancer

BACKGROUND The present study is aimed to identify genetic pathways correlated with chemoresistance in epithelial ovarian cancer (EOC). METHODS We compared the molecular profiles of 23 tumour biopsies of stage III-IV (training set) at primary surgery, before chemotherapy, to the profile from the same patients at second surgery, after several lines of platinum (Pt)-based chemotherapy when the tumours were resistant. In the hypothesis that identified markers were related to Pt-resistance and to prognosis, we validated this signature in 52 EOC taken at primary surgery (validation set) selected to be either very sensitive to the first line therapy, i.e. not relapsing before one year from the end of therapy, or resistant, i.e. relapsing within 6 months from the end of therapy. RESULTS In the training set, we identified a resistance signature indicative of the activation of epithelial to mesenchymal transition (EMT) by transforming growth factor (TGF)-beta pathway. We then validated this signature in 52 EOC taken at primary surgery (validation set). Some genes involved in EMT, such as BMP and activin membrane-bound inhibitor (BAMBI), and mir-141 resulted in association with overall or progression free survival. CONCLUSION Some genes involved in EMT were associated to overall or progression free survival, suggesting EMT as vital to the resistance mechanisms.

Analysis of Gene Expression in Early-Stage Ovarian Cancer

Purpose: Gene expression profile was analyzed in 68 stage I and 15 borderline ovarian cancers to determine if different clinical features of stage I ovarian cancer such as histotype, grade, and survival are related to differential gene expression. Experimental Design: Tumors were obtained directly at surgery and immediately frozen in liquid nitrogen until analysis. Glass arrays containing 16,000 genes were used in a dual-color assay labeling protocol. Results: Unsupervised analysis identified eight major patient partitions, one of which was statistically associated to overall survival, grading, and histotype and another with grading and histotype. Supervised analysis allowed detection of gene profiles clearly associated to histotype or to degree of differentiation. No difference was found between borderline and grade 1 tumors. As to recurrence, a subset of genes able to differentiate relapsers from nonrelapsers was identified. Among these, cyclin E and minichromosome maintenance protein 5 were found particularly relevant, as their expression was inversely correlated to progression-free survival (P = 0.00033 and 0.017, respectively). Conclusions: Specific molecular signatures define different histotypes and prognosis of stage I ovarian cancer. Mucinous and clear cells histotypes can be distinguished from the others regardless of tumor grade. Cyclin E and minichromosome maintenance protein 5, whose expression was found previously to be related to a bad prognosis of advanced ovarian cancer, appear to be potential prognostic markers in stage I ovarian cancer too, independent of other pathologic and clinical variables.

miRNA Landscape in Stage I Epithelial Ovarian Cancer Defines the Histotype Specificities

Purpose: Epithelial ovarian cancer (EOC) is one of the most lethal gynecologic diseases, with survival rate virtually unchanged for the past 30 years. EOC comprises different histotypes with molecular and clinical heterogeneity, but up till now the present gold standard platinum-based treatment has been conducted without any patient stratification. The aim of the present study is to generate microRNA (miRNA) profiles characteristic of each stage I EOC histotype, to identify subtype-specific biomarkers to improve our understanding underlying the tumor mechanisms. Experimental Design: A collection of 257 snap-frozen stage I EOC tumor biopsies was gathered together from three tumor tissue collections and stratified into independent training (n = 183) and validation sets (n = 74). Microarray and quantitative real-time PCR (qRT-PCR) were used to generate and validate the histotype-specific markers. A novel dedicated resampling inferential strategy was developed and applied to identify the highest reproducible results. mRNA and miRNA profiles were integrated to identify novel regulatory circuits. Results: Robust miRNA markers for clear cell and mucinous histotypes were found. Specifically, the clear cell histotype is characterized by a five-fold (log scale) higher expression of miR-30a and miR-30a*, whereas mucinous histotype has five-fold (log scale) higher levels of miR-192/194. Furthermore, a mucinous-specific regulatory loop involving miR-192/194 cluster and a differential regulation of E2F3 in clear cell histotype were identified. Conclusions: Our findings showed that stage I EOC histotypes have their own characteristic miRNA expression and specific regulatory circuits. Clin Cancer Res; 19(15); 4114–23. ©2013 AACR.

Characterization of a new trabectedin-resistant myxoid liposarcoma cell line that shows collateral sensitivity to methylating agents

Myxoid Liposarcomas (MLS), characterized by the expression of FUS‐CHOP fusion gene are clinically very sensitive to the DNA binding antitumor agent, trabectedin. However, resistance eventually occurs, preventing disease eradication. To investigate the mechanisms of resistance, a trabectedin resistant cell line, 402‐91/ET, was developed. The resistance to trabectedin was not related to the expression of MDR related proteins, uptake/efflux of trabectedin or GSH levels that were similar in parental and resistant cells. The 402‐91/ET cells were hypersensitive to UV light because of a nucleotide excision repair defect: XPG complementation decreased sensitivity to UV rays, but only partially to trabectedin. 402‐91/ET cells showed collateral sensitivity to temozolomide due to the lack of O6‐methylguanine‐DNA‐methyltransferase (MGMT) activity, related to the hypermethylation of MGMT promoter. In 402‐91 cells chromatin immunoprecipitation (ChIP) assays showed that FUS‐CHOP was bound to the PTX3 and FN1 gene promoters, as previously described, and trabectedin caused FUS‐CHOP detachment from DNA. Here we report that, in contrast, in 402‐91/ET cells, FUS‐CHOP was not bound to these promoters. Differences in the modulation of transcription of genes involved in different pathways including signal transduction, apoptosis and stress response between the two cell lines were found. Trabectedin activates the transcription of genes involved in the adipogenic‐program such as c/EBPα and β, in 402‐91 but not in 402‐91/ET cell lines. The collateral sensitivity of 402‐91/ET to temozolomide provides the rationale to investigate the potential use of methylating agents in MLS patients resistant to trabectedin.

The zinc finger gene ZIC2 has features of an oncogene and its overexpression correlates strongly with the clinical course of epithelial ovarian cancer.

Purpose: Epithelial ovarian tumors (EOT) are among the most lethal of malignancies in women. We have previously identified ZIC2 as expressed at a higher level in samples of a malignant form (MAL) of EOT than in samples of a form with low malignant potential (LMP). We have now investigated the role of ZIC2 in driving tumor growth and its association with clinical outcomes. Experimental Design: ZIC2 expression levels were analyzed in two independent tumor tissue collections of LMP and MAL. In vitro experiments aimed to test the role of ZIC2 as a transforming gene. Cox models were used to correlate ZIC2 expression with clinical endpoints. Results: ZIC2 expression was about 40-fold in terms of mRNA and about 17-fold in terms of protein in MAL (n = 193) versus LMP (n = 39) tumors. ZIC2 mRNA levels were high in MAL cell lines but undetectable in LMP cell lines. Overexpression of ZIC2 was localized to the nucleus. ZIC2 overexpression increases the growth rate and foci formation of NIH3T3 cells and stimulates anchorage-independent colony formation; downregulation of ZIC2 decreases the growth rate of MAL cell lines. Zinc finger domains 1 and 2 are required for transforming activity. In stage I MAL, ZIC2 expression was significantly associated with overall survival in both univariate (P = 0.046) and multivariate model (P = 0.049). Conclusions: ZIC2, a transcription factor related to the sonic hedgehog pathway, is a strong discriminant between MAL and LMP tumors: it may be a major determinant of outcome of EOTs. Clin Cancer Res; 18(16); 4313–24. ©2012 AACR.

A systems biology approach to investigate the mechanism of action of trabectedin in a model of myelomonocytic leukemia

This study was designed to investigate the mode of action of trabectedin in myelomonocytic leukemia cells by applying systems biology approaches to mine gene expression profiling data and pharmacological assessment of the cellular effects. Significant enrichment was found in regulons of target genes inferred for specific transcription factors, among which MAFB was the most upregulated after treatment and was central in the transcriptional network likely to be relevant for the specific therapeutic effects of trabectedin against myelomonocytic cells. Using the Connectivity Map, similarity among transcriptional signatures elicited by treatment with different compounds was investigated, showing a high degree of similarity between transcriptional signatures of trabectedin and those of the topoisomerase I inhibitor, irinotecan, and an anti-dopaminergic antagonist, thioridazine. The study highlights the potential importance of systems biology approaches to generate new hypotheses that are experimentally testable to define the specificity of the mechanism of action of drugs.

Correction: Everolimus (EVE) and exemestane (EXE) in patients with advanced breast cancer aged ≥ 65 years: new lessons for clinical practice from the EVA study

BACKGROUND The present analysis focuses on real-world data of Everolimus-Exemestane in advanced HR+ve, HER2-ve elderly breast cancer patients (aged 65 years) included in the EVA study, with unique findings in those aged 70 years. METHODS Data are collected from clinical records and analysed according to age cut-off (< 65 years; 65 - 69 years and {greater than or equal to} 70 years). Relationship of analyzed variables with response were tested by mean of a Mantel-Haenszel chi square test. Time to event analysis was described by Kaplan Meier approach and association with baseline characteristics was analysed by stratified log-rank test and proportional hazard model. RESULTS From July 2013 to December 2015, the EVA study enrolled overall 404 pts. 154 patients out of 404 (38,1%) were aged {greater than or equal to} 65 years, of whom 87 were {greater than or equal to} 70 years. Median duration of EVE treatment was 28.5 weeks (95% CI 19.0 - 33.8) in patients aged 65-69 years and 24,4 weeks (95% CI 19,2 - 33,2) in those aged {greater than or equal to} 70 years. Fewer patients aged 65 years received the highest EVE Dose-Intensity (>7.5 mg/day) in comparison to younger patients (49,6% vs. 66,8%). Grade 3–4 toxicities occurred to 55 patients (35,7%), mainly stomatitis (10,9%), rash (5,8%) and non-infectious pneumonitis (NIP) (3,6%). Some toxicities, such as weight loss and anaemia were peculiarly observed in patients aged {greater than or equal to} 70 years. Five treatment-related deaths were collected (3,2%). CONCLUSIONS EVE-EXE combination remains one of the potential treatments in HR+ patients also for elderly ones.

PO64 METRONOMIC CHEMOTHERAPY (CHT) COMBINATION OF VINORELBINE (VRL) AND CAPECITABINE (CAPE) IN HER2- ADVANCED BREAST CANCER (ABC) PATIENTS (PTS) DOES NOT IMPAIR GLOBAL QOL. FIRST RESULTS OF THE VICTOR-2 STUDY

age distribution at the time of MBC diagnosis: 41-57 years (n=3) and 76/79 years (n=2). Two patients had solitary metastatic lesions (bone, n=2; lung, n=1), one patient had extensive bone metastases, and one patient had multiple bony and pulmonary metastases. In only one of the five cases did the patient receive chemotherapy in the supposed palliative situation. Discussion: There are patients who, despite the diagnosis of distant metastases, may be considered cured of their disease; however, these cases are rare. The long-term survivors in our study cohort comprised a relatively heterogeneous group with regard to age at MBC diagnosis, therapy and metastatic sites. The factors contributing to the quite rare and felicitous case of long-term survival or even cure, can hardly be evaluated systematically and remain a black box. It appears, however, that aggressive chemotherapy-containing regimens, are not the key to solving the mystery of this black box.

Abstract B64: Gene expression profile of a liposarcoma mixoid cell line selected in vitro for resistance to Trabectedin

Introduction: Trabectedin is a marine alkaloid originally isolated from Ecteinascidia turbinata approved in Europe for the second line of therapy in soft tissue sarcomas (STS). Here we characterize and compare the gene expression profile of 402‐91/ET Res liposarcoma cells obtained after continuous exposure to trabectedin in vitro with that of their parental cell line 402‐91. Methods: Drug sensitivity was measured by colony assay and Flow Cytometric analysis was used to analyze cell cycle perturbations. Microarray analysis between sensitive and 402‐91/ET Res cells was performed using commercially available arrays onto which 44K oligos were pre‐spotted. Gene expression analysis was performed with “R” package software. Pathway analysis was performed using Metacore software. qRT‐PCR was used for data validation. Statistical analysis was performed using Graphpad software . Results: 402‐91/ET Res cells were selected in vitro for their stable resistance to trabectedin by step‐wise increase in the drug concentration (25 nM) lasting 14 months. Resistance to Trabectedin was stable over 22 months without compound exposure. Cells were cross resistant to melphalan, but more sensitive to taxanes, vinblastine, temozolomide and UV rays. Resistance was not associated to the expression of MDR proteins as well as different uptake/efflux. Cell cycle analysis revealed that trabectedin is able to induce a G2‐M block in the sensitive cell line but not in the resistant one. The expression levels of the FUS‐CHOP gene were comparable between the 402‐91 and 402‐91/ET Res cells but with a different trans‐activation ability. Microarray analysis identified 511 probes set able to discriminate between sensitive and resistant cell lines. Pathway analysis revealed that most of the genes altered in the 402‐91/ET Res cells were associated with liposarcoma phenotype and functionally involved in the CREB pathway as well as control of apoptosis. Conclusion: Data suggests that in the 402‐91/ET Res cells FUS‐CHOP trans‐activation activity has been impaired. Studies are in progress to address whether these mechanisms are implicated in sensitivity of liposarcoma cell lines to trabectedin. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B64.