Luca Porcu

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.

Does Surgery Improve Survival of Patients with Malignant Pleural Mesothelioma?: A Multicenter Retrospective Analysis of 1365 Consecutive Patients

Background: Surgery with pleurectomy/decortication (P/D) or extrapleural pneumonectomy (EPP) can be an option for selected patients with resectable malignant pleural mesothelioma (MPM). The aim of this study was to investigate the impact of surgical treatment on the outcome of patients with MPM. Methods: We retrospectively reviewed data from 1365 consecutive patients with histologically proven MPM, treated from 1982 to 2012 in six Institutions. Patients received chemotherapy alone (n = 172), best supportive care (n = 690), or surgical treatment (n = 503), by either P/D (n = 202) or EPP (n = 301) with or without chemotherapy. Results: After a median follow-up of 6.7 years (range, 1.1–14.8), 230 patients (16.8%) were alive; median survival for patients who received palliative treatment or chemotherapy alone, P/D, and EPP were 11.7 (95% CI, 10.5–12.5), 20.5 (95% CI, 18.2–23.1), and 18.8 (95% CI, 17.2–20.9) months, respectively. The 30-day mortality was 2.6% after P/D and 4.1% after EPP (p = 0.401). According to multivariate analysis (n = 1227), age less than 70, epithelial histology, and chemotherapy were independent favorable prognostic factors. In the subset of 313 patients (25.5%) with all favorable prognostic factors, median survival was 18.6 months after medical therapy alone, 24.6 months after P/D, and 20.9 months after EPP (p = 0.596). Conclusions: Our data suggest that patients with good prognostic factors had a similar survival whether they received medical therapy only, P/D, or EPP. The modest benefit observed after surgery during medical treatment requires further investigation, and a large multicenter, randomized trial, testing P/D after induction chemotherapy versus chemotherapy alone in MPM patients with good prognostic factors, is needed.

Molecular isoforms of high-mobility group box 1 are mechanistic biomarkers for epilepsy

Approximately 30% of epilepsy patients do not respond to antiepileptic drugs, representing an unmet medical need. There is evidence that neuroinflammation plays a pathogenic role in drug-resistant epilepsy. The high-mobility group box 1 (HMGB1)/TLR4 axis is a key initiator of neuroinflammation following epileptogenic injuries, and its activation contributes to seizure generation in animal models. However, further work is required to understand the role of HMGB1 and its isoforms in epileptogenesis and drug resistance. Using a combination of animal models and sera from clinically well-characterized patients, we have demonstrated that there are dynamic changes in HMGB1 isoforms in the brain and blood of animals undergoing epileptogenesis. The pathologic disulfide HMGB1 isoform progressively increased in blood before epilepsy onset and prospectively identified animals that developed the disease. Consistent with animal data, we observed early expression of disulfide HMGB1 in patients with newly diagnosed epilepsy, and its persistence was associated with subsequent seizures. In contrast with patients with well-controlled epilepsy, patients with chronic, drug-refractory epilepsy persistently expressed the acetylated, disulfide HMGB1 isoforms. Moreover, treatment of animals with antiinflammatory drugs during epileptogenesis prevented both disease progression and blood increase in HMGB1 isoforms. Our data suggest that HMGB1 isoforms are mechanistic biomarkers for epileptogenesis and drug-resistant epilepsy in humans, necessitating evaluation in larger-scale prospective studies.

Comparison of in vitro and in vivo biological effects of trabectedin, lurbinectedin (PM01183) and Zalypsis® (PM00104).

This study: (i) investigated the in vitro cytotoxicity and mode of action of lurbinectedin (PM01183) and Zalypsis® (PM00104) compared with trabectedin in cell lines deficient in specific mechanisms of repair, (ii) evaluated their in vivo antitumor activity against a series of murine tumors and human xenografts. The antiproliferative activity, the DNA damage and the cell cycle perturbations induced by the three compounds on tumor lines were very similar. Nucleotide Excision Repair (NER) deficient cells were approximately fourfold more resistant to trabectedin, lurbinectedin and Zalypsis®. Cells deficient in non‐homologous end joining (NHEJ), MRN complex and translesion synthesis (TLS) were slightly more sensitive to the three compounds (approximately fivefold) while cells deficient in homologous recombination (HR) were markedly more sensitive (150–200‐fold). All three compounds showed a good antitumor activity in several in vivo models. Lurbinectedin and trabectedin had a similar pattern of antitumor activity in murine tumors and in xenografts, whereas Zalypsis® appeared to have a distinct spectrum of activity. The fact that no relationship whatsoever was found between the in vitro cytotoxic potency and the in vivo antitumor activity, suggests that in addition to direct cytotoxic mechanisms other host‐mediated effects are involved in the in vivo pharmacological effects.

The Third Italian Consensus Conference for Malignant Pleural Mesothelioma: State of the art and recommendations.

Malignant Pleural Mesothelioma (MPM) remains a relevant public health issue, and asbestos exposure is the most relevant risk factor. The incidence has considerably and constantly increased over the past two decades in the industrialized countries and is expected to peak in 2020-2025. In Italy, a standardized-rate incidence in 2011 among men was 3.5 and 1.25 per 100,000 in men and women, respectively, and wide differences are noted among different geographic areas. The disease remains challenging in terms of diagnosis, staging and treatment and an optimal strategy has not yet been clearly defined. The Third Italian Multidisciplinary Consensus Conference on Malignant Pleural Mesothelioma was held in Bari (Italy) in January 30-31, 2015. This Consensus has provided updated recommendations on the MPM management for health institutions, clinicians and patients.

Cognitive deficits and brain myo-Inositol are early biomarkers of epileptogenesis in a rat model of epilepsy

One major unmet clinical need in epilepsy is the identification of therapies to prevent or arrest epilepsy development in patients exposed to a potential epileptogenic insult. The development of such treatments has been hampered by the lack of non-invasive biomarkers that could be used to identify the patients at-risk, thereby allowing to design affordable clinical studies. Our goal was to test the predictive value of cognitive deficits and brain astrocyte activation for the development of epilepsy following a potential epileptogenic injury. We used a model of epilepsy induced by pilocarpine-evoked status epilepticus (SE) in 21-day old rats where 60-70% of animals develop spontaneous seizures after around 70days, although SE is similar in all rats. Learning was evaluated in the Morris water-maze at days 15 and 65 post-SE, each time followed by proton magnetic resonance spectroscopy for measuring hippocampal myo-Inositol levels, a marker of astrocyte activation. Rats were video-EEG monitored for two weeks at seven months post-SE to detect spontaneous seizures, then brain histology was done. Behavioral and imaging data were retrospectively analysed in epileptic rats and compared with non-epileptic and control animals. Rats displayed spatial learning deficits within three weeks from SE. However, only epilepsy-prone rats showed accelerated forgetting and reduced learning rate compared to both rats not developing epilepsy and controls. These deficits were associated with reduced hippocampal neurogenesis. myo-Inositol levels increased transiently in the hippocampus of SE-rats not developing epilepsy while this increase persisted until spontaneous seizures onset in epilepsy-prone rats, being associated with a local increase in S100β-positive astrocytes. Neuronal cell loss was similar in all SE-rats. Our data show that behavioral deficits, together with a non-invasive marker of astrocyte activation, predict which rats develop epilepsy after an acute injury. These measures have potential clinical relevance for identifying individuals at-risk for developing epilepsy following exposure to epileptogenic insults, and consequently, for designing adequately powered antiepileptogenesis trials.

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.

Prognostic factors for survival in patients with metastatic renal cell carcinoma treated with targeted therapies

Background:The most important prognostic factors for survival in patients with metastatic renal cell carcinoma (mRCC) were evaluated in the era of cytokine therapy, and only recently were revalidating in patients receiving targeted therapies (TTs).Methods:Clinical data for consecutive patients with mRCC who received TTs were retrieved from the database of Istituto Nazionale dei Tumori of Milan. Variables with a significant association with overall survival (OS) were estimated by proportional hazard regression, and a backward stepwise multivariate analysis identified the independent prognostic factors.Results:Data for 336 consecutive patients treated with TTs for RCC during the period 2004–2011 were evaluated. According to the Motzer classification, 32% patients were low risk, 48% were intermediate risk and 20% were poor risk. One hundred and sixty-seven (49.7%) patients received one TT, 116 (34.5%) received a second-line TT, 42 (12.5%) a third-line TT and 11 (3.3%) patients received a fourth-line TT. The median OS was 24 months (95% CI 20.0, 27.0) and the 5-year OS rate was 24.6% (95% CI 18.7, 30.8%). In the uni- and multivariate analysis Motzer risk classification, Fuhrman grade and previous cytokine therapy were identified as independent prognostic factors (P<0.01).Conclusion:The Motzer classification was confirmed as an independent prognostic factor for OS in patients with mRCC receiving TTs. Additionally, Fuhrman grade and previous cytokine therapy were independent prognostic factors for clinical outcome.

Predictors of long-term response to abiraterone in patients with metastastic castration-resistant prostate cancer: A retrospective cohort study

We aimed to identify clinical predictors of long-term response to abiraterone (defined as >12 months drug exposure) in a retrospective cohort of metastatic castration-resistant prostate cancer patients treated in post-docetaxel setting at 24 Italian centers. The Cox proportional hazards model was used to analyze the association between clinical features and the duration of drug exposure. Results were expressed as hazard ratios (HR) with associated 95% confidence intervals (CI). A total of 143 patients met the inclusion criteria. Their median age was 73 years, median Gleason score 8 and median abiraterone exposure 20 months. At the univariate analysis, a significant correlation with the duration of abiraterone exposure was found for Gleason score (HR 0.82, 95% CI 0.71-0.96; p=0.012), PSA (HR 1.10, 95% CI 1.03-1.18; p=0.08) and lactic dehydrogenase levels (HR 1.22, 95% CI 1.02-1.46; p=0.027), while the association between lower alkaline phosphatase levels and treatment duration was marginally significant (HR 1.07, 95% CI 0.99-1.16; p=0.074). Only PSA and Gleason score were predictive of long-term treatment duration in the multivariate analysis. No other clinical factors resulted to be predictive of sustained response to abiraterone, including metastatic disease at diagnosis and visceral disease, suggesting that all subgroups of patients may derive a substantial clinical benefit from abiraterone treatment. These findings need to be validated in prospective, larger studies.

Efficacy and Safety of Bevacizumab Combined With Fluoropyrimidine Monotherapy for Unfit or Older Patients With Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis

Micro‐Abstract Whether bevacizumab represents a feasible option for the first‐line treatment of unfit and elderly patients with metastatic colorectal cancer remains controversial. The present meta‐analysis included data from 782 patients and provides evidence for the clinical benefit yielded in terms of progression‐free survival and overall survival by the addition of bevacizumab to first‐line fluoropyrimidine‐based chemotherapy for these complex patients. Background: Whether bevacizumab represents a feasible option for the first‐line treatment of unfit and elderly patients with metastatic colorectal cancer (mCRC) remains controversial. The present systematic review and meta‐analysis evaluated the efficacy and safety data of bevacizumab combined with first‐line fluoropyrimidine monochemotherapy for these complex patients. Patients and Methods: A systematic search of the published data was conducted through May 31, 2016. The random‐effects model was used to combine the effect estimates and the I2 index to quantify the between‐study heterogeneity unexplained by sampling error. Results: We included 3 randomized controlled trials, 4 single‐arm phase II trials, and 1 prospective cohort study in the present meta‐analysis (n = 782). The monochemotherapy administered was capecitabine in 531 patients (67.9%) and 5‐fluorouracil in 251 (32.1%); 500 (63.9%) also received bevacizumab. The median age was 75 years, 441 patients (56.4%) were men, and the Eastern Cooperative Oncology Group performance status was 0 to 1 in 684 patients (87.7%). The combination with bevacizumab produced advantages in terms of both progression‐free survival (hazard ratio, 0.52; 95% confidence interval, 0.43‐0.64; P < .00001; I2 = 0%) and overall survival (HR, 0.79; 95% CI, 0.64‐0.98; P = .03; I2 = 0%). The pooled effect estimates of the randomized controlled trials have been previously reported. As expected, all‐grade hypertension (27% vs. 4.9%), bleeding (24% vs. 6.4%), thromboembolic events (10% vs. 5%), and proteinuria (25.6% vs. 8.2%) were more frequent in the bevacizumab combination group. Conclusion: Adding bevacizumab to first‐line fluoropyrimidine monochemotherapy significantly improved progression‐free and overall survival in unfit and elderly patients with mCRC, with a manageable safety profile and no unexpected toxicities.