Paolo Bironzo

Targeted Next-Generation Sequencing of Cancer Genes in Advanced Stage Malignant Pleural Mesothelioma: A Retrospective Study

Introduction: Malignant pleural mesothelioma (MPM) is a rare malignant disease, and the understanding of molecular pathogenesis has lagged behind other malignancies. Methods: A series of 123 formalin-fixed, paraffin-embedded tissue samples with clinical annotations were retrospectively tested with a commercial library kit (Ion AmpliSeq Cancer Hotspot Panel v.2, Life Technologies, Grand Island, NY) to investigate 50 genes plus other two, BRCA1-associated protein-1 (BAP-1) and neurofibromatosis-2 (NF2), frequently altered in MPM. DNA was obtained from tissues after manual microdissection and enriched for at least 50% cancer cells. Variations affecting protein stability or previously correlated to cancer, more frequently identified (≥25 patients with at least 10% of allelic frequency), were subsequently evaluated by Sanger sequencing. Immunohistochemistry staining for BAP1 and NF2 proteins was also performed. Results: The commonest genetic variations were clustered in two main pathways: the p53/DNA repair (TP53, SMACB1, and BAP1) and phosphatidylinositol 3-kinase–AKT pathways (PDGFRA, KIT, KDR, HRAS, PIK3CA, STK11, and NF2). PIK3CA:c.1173A>G mutation, STK11:rs2075606 (T>C), or TP53:rs1042522 (Pro/Pro) was significantly associated with time to progressive disease (TTPD; all p values < 0.01). Furthermore, the accumulation of genetic alterations correlated with shorter TTPD and reduced overall survival (TTPD p value = 0.02, overall survival p value = 0.04). BAP1 genetic variations identified were mainly located in exons 13 and 17, and BAP1 nonsynonymous variations were significantly correlated with BAP1 protein nuclear localization. Conclusion: Next-generation sequencing was applied to a relatively large retrospective series of MPM using formalin-fixed, paraffin-embedded archival material. Our results indicate a complex mutational landscape with a higher number of genetic variations in the p53/DNA repair and phosphatidylinositol 3-kinase pathways, some of them with prognostic value.

Understanding and overcoming the mechanisms of primary and acquired resistance to abiraterone and enzalutamide in castration resistant prostate cancer

In recent years, in castration resistant prostate cancer (CRPC), several new drugs have been approved that prolong overall survival, including enzalutamide and abiraterone, two new-generation hormonal therapies. Despite the demonstrated benefit of these agents, not all patients with CRPC are responsive to treatment, the gain in median progression-free survival with these therapies compared to standard of care is, rather disappointingly, still less than six months and the appearance of acquired resistance is almost universal. Approximately one third of patients treated with abiraterone and 25% of those treated with enzalutamide show primary resistance to these agents. Even if the mechanisms of resistance to these agents are not fully defined, many hypotheses are emerging, including systemic and intratumoral androgen biosynthesis up-regulation, androgen receptor (AR) gene mutations and amplifications, alteration of pathways involved in cross-talk with AR signaling, glucocorticoid receptor overexpression, neuroendocrine differentiation, immune system deregulation and others. The aim of this paper is to review currently available data about mechanisms of resistance to abiraterone and enzalutamide, and to discuss how these mechanisms could be potentially overcome through novel therapeutic agents.

Strategies for managing ACTH dependent mineralocorticoid excess induced by abiraterone

BACKGROUND Abiraterone strongly inhibits androgen synthesis but may lead to an increase in mineralocorticoid hormones that may impair its long term tolerability in patients with prostate cancer. How to implement available therapies in the management and prevention of these potential side effects is a matter of current clinical research. METHODS The acute and long term consequences of mineralocorticoid excess and the effects of available treatments have been reviewed. Prospective studies in which abiraterone was employed were identified to assess the frequency and severity of the mineralocorticoid excess syndrome and the efficacy of ameliorating therapeutic approaches. RESULTS Glucocorticoids to inhibit the ACTH increase that drives mineralocorticoid synthesis and mineralocorticoid receptor (MR) antagonists can be used in the management of the abiraterone-induced mineralocorticoid excess syndrome. Phase I and II trials of abiraterone without additional therapies revealed that mineralocorticoid excess symptoms occur in the majority of patients. Eplerenone, a specific MR antagonist, seems to be effective but it does not control the mineralocorticoid excess. Glucorticoid supplementation to control ACTH drive is therefore needed. In several randomized trials the addition of prednisone (10mg daily) to abiraterone was not able to prevent mineralocorticoid excess syndrome in many cases and thus cannot be considered the gold standard. CONCLUSION At present, the best conceivable treatment for managing the abiraterone-induced mineralocorticoid excess consists of the administration of glucocorticoid replacement at the lowest effective dose ± MR antagonists and salt deprivation. The drug doses should be modulated by monitoring blood pressure, fluid retention and potassium levels during therapy.

DNA repair gene expression level in peripheral blood and tumour tissue from non-small cell lung cancer and head and neck squamous cell cancer patients

BACKGROUND The nucleotide excision repair pathway is crucial for cellular DNA integrity and the ERCC1 helicase is also potentially involved in resistance to platinum-based chemotherapy, and high levels of ERCC1 mRNA in tumours have been associated with cisplatin resistance in different human cancers. The aim of this work was to investigate the correlation between DNA repair gene expression levels in tumour tissue, normal tissue and peripheral blood samples from patients with two common human cancers, non-small cell lung cancer (NSCLC) and squamous cell carcinoma of the head and neck (HNSCC), to test if blood gene expression could be a proxy for tumour tissue gene expression to predict response to platinum-based chemotherapy. METHODS Using RT-qPCR we determined ERCC1, ERCC2, ERCC4, XPA, XPC, XRCC1, XRCC3, APEX, OGG1, MGMT mRNA levels in fresh NSCLC, normal lung and HNSCC tissue, as well as blood, from NSCLC and HNSCC patients who were treated surgically. RESULTS Target gene expression in NSCLC and HNSCC tissue was higher than in blood. A statistically significant correlation (p<0.05) was found between target gene mRNA expression in tumour tissue and blood, in particular ERCC1, MGMT, XPC, XRCC1 and XRCC3 in NSCLC and APEX, ERCC1, ERCC2, ERCC4, XRCC1 and XRCC3 in HNSCC. CONCLUSIONS The existence of a significant correlation between blood and tumour tissue expression of some genes of clinical interest, such as ERCC1 in NSCLC and HNSCC, could allow the introduction in clinical practice of a simple test that would measure mRNA levels of DNA repair genes in peripheral blood samples instead of tissue samples to determine prognostic and predictive factors in NSCLC and HNSCC patients.

Addressing the unmet need in lung cancer: The potential of immuno-oncology

Chemotherapy is currently the standard of care for non-oncogene-driven advanced non-small cell lung cancer (NSCLC). Due to improvements in chemotherapeutic choices and supportive care, patients currently typically undergo multiple lines of chemotherapy as their disease progresses. Although treatments have improved over recent years, limited benefits are seen, especially in patients receiving later-line chemotherapy, as response rates can be low, response duration short and survival poor. Furthermore, only a small percentage of patients derive benefit from later-line therapy, with most experiencing deteriorating quality of life and significant toxicities. More recently, molecular targeted therapies have provided improvements in outcomes. However, these treatments only offer a clear benefit in subsets of tumours harbouring the appropriate genomic alteration (mutation, amplification, translocation). Most of the genomic abnormalities susceptible to therapeutic intervention are detected in adenocarcinoma, mainly in never smokers, while alterations in the genome of other histological subtypes are known but specific agents targeting these alterations have yet to be developed. Thus, the therapeutic management of these subtypes represents an ongoing challenge. Recent advances in immunotherapy have highlighted the potential of immuno-oncology based treatments for NSCLC, offering the potential to provide durable responses and outcomes regardless of histology or mutation status. This review discusses the current unmet medical needs in NSCLC, the limits of current first-line and later-line chemotherapy and targeted agents, and the emergence of new therapeutic strategies.

Moving from histological subtyping to molecular characterization: new treatment opportunities in advanced non-small-cell lung cancer

Over the last 10 years, the systemic treatment of advanced non-small-cell lung cancer has progressively moved away from the ‘one-size-fits-all’ approach to histological subtyping. Currently, there is a progressive implementation of targeted therapies based on specific molecular characteristics such as the EGF receptor sensitizing mutations and the anaplastic lymphoma kinase rearrangements. Despite the availability of effective agents against these abnormalities, acquired resistance is still a major issue. A new generation of tyrosine kinase inhibitors for EGF receptor and anaplastic lymphoma kinase targeting acquired resistance mechanisms have been recently investigated. Several promising tyrosine kinase inhibitors that hit other targets are also in clinical development, including: rat sarcoma gene/MEK, BRAF1, PIK3A, c-mesenchymal-epithelial transition, c-ros oncogene 1, rearranged during transfection, human EGFR 2, FGFR, VEGFR, PDGFR and discoidin death receptor 2. Furthermore, new advances in immunology have been achieved through the discovery of vaccines and immune checkpoint pathways such as the cytotoxic T-lymphocyte-associated antigen-4, programmed cell death protein 1 and its ligands.

Neoadjuvant chemo-radiotherapy for locally advanced esophageal cancer: a monocentric study

AIMS AND BACKGROUND Multimodal therapy is a keystone of care in advanced esophageal cancer. Although neoadjuvant chemoradiotherapy is known to provide a survival advantage in selected cases, reliable prognostic and response predictive factors remain elusive. We report the outcome in a series of esophageal cancer patients treated at our center and the results of a retrospective analysis of epidermal growth factor receptor (EGFR) expression and EGFR/HER2 gene copy numbers taken as possible prognostic and predictive factors. METHODS AND STUDY DESIGN Between 2001 and 2009, a total of 40 consecutive patients (34 men and 6 women; median age, 59 years) were treated for esophageal cancer. TREATMENT cisplatin, 80 mg/m² day 1, and 5-fluorouracil, 800 mg/m²/24 h on days 1-5, every 21 days, concomitant with 3D-conformal radiotherapy (54-59.4 in 30-33 fractions) for three up to four cycles. Surgery was performed in eligible patients 6-8 weeks after chemoradiation. EGFR expression and EGFR/HER2 amplification and gene copy number were studied by immunohistochemical analysis and fluorescence in situ hybridization, respectively. RESULTS Acceptable toxicity following chemoradiation was recorded, with G3-G4 hematological toxicity in 20% of patients and G3-G4 dysphagia in less than 10%; 14 (35%) patients achieved complete response and 19 (48%) partial response; 18 underwent surgery after chemoradiation, of which 8 (20%) achieved pathologic complete response. The median survival was 29 months (95% CI, 25.7-32.1): 42 months for the resected and 20 for the unresected patients. EGFR and HER2 analysis in 28 patients showed that 89% had immunohistochemical EGFR expression, with 5 cases of EGFR and 10 of HER2 gene gain without a significant difference in response rate and survival in these patient subgroups. CONCLUSIONS Our results suggest a better outcome in patients who underwent surgery after chemoradiation. A larger sample size is necessary to clarify the role of EGFR and HER2 gene gain in predict response and survival.

Bromodomain inhibition exerts its therapeutic potential in malignant pleural mesothelioma by promoting immunogenic cell death and changing the tumor immune-environment

ABSTRACT Systemic treatment of malignant pleural mesothelioma (MPM) is moderately active for the intrinsic pharmacological resistance of MPM cell and its ability to induce an immune suppressive environment. Here we showed that the expression of bromodomain (BRD) proteins BRD2, BRD4 and BRD9 was significantly higher in human primary MPM cells compared to normal mesothelial cells (HMC). Nanomolar concentrations of bromodomain inhibitors (BBIs) JQ1 or OTX015 impaired patient-derived MPM cell proliferation and induced cell-cycle arrest without affecting apoptosis. Importantly, BBIs primed MPM cells for immunogenic cell death, by increasing extracellular release of ATP and HMGB1, and by promoting membrane exposure of calreticulin and ERp57. Accordingly, BBIs activated dendritic cell (DC)-mediated phagocytosis and expansion of CD8+ T-lymphocyte clones endorsed with antitumor cytotoxic activity. BBIs reduced the expression of the immune checkpoint ligand PD-L1 in MPM cells; while both CD8+ and CD4+ T-lymphocytes co-cultured with JQ1-treated MPM cells decreased PD-1 expression, suggesting a disruption of the immune-suppressive PD-L1/PD-1 axis. Additionally, BBIs reduced the expansion of myeloid-derived suppressor cells (MDSC) induced by MPM cells. Finally, a preclinical model of MPM confirmed that the anti-tumor efficacy of JQ1 was largely due to its ability to restore an immune-active environment, by increasing intra-tumor DC and CD8+ T-lymphocytes, and decreasing MDSC. Thereby, we propose that, among novel drugs, BBIs should be investigated for MPM treatment for their combined activity on both tumor cells and surrounding immune-environment.

Antiandrogen withdrawal syndrome (AAWS) in the treatment of patients with prostate cancer

Antiandrogen withdrawal syndrome is an unpredictable event diagnosed in patients with hormone-sensitive prostate cancer treated with combined androgen blockade therapy. It is defined by prostate-specific antigen value reduction, occasionally associated with a radiological response, that occurs 4-6 weeks after first-generation antiandrogen therapy discontinuation. New-generation hormonal therapies, such as enzalutamide and abiraterone acetate, improved the overall survival in patients with metastatic castration-resistant prostate cancer, and recent trials have also shown the efficacy of abiraterone in hormone-sensitive disease. In the last few years, several case reports and retrospective studies suggested that the withdrawal syndrome may also occur with these new drugs. This review summarizes literature data and hypothesis about the biological rationale underlying the syndrome and its potential clinical relevance, focusing mainly on new-generation hormonal therapies. Several in vitro studies suggest that androgen receptor gain-of-function mutations are involved in this syndrome, shifting the antiandrogen activity from antagonist to agonist. Several different drug-specific point mutations have been reported. The association of the withdrawal syndrome for enzalutamide and abiraterone needs confirmation by additional investigations. However, new-generation hormonal therapies being increasingly used in all stages of disease, more patients may experience the syndrome when stopping the treatment at the time of disease progression, although the clinical relevance of this phenomenon in the management of metastatic castration-resistant prostate cancer remains to be defined.

A review of guidelines for lung cancer

Clinical practice guidelines include recommendations intended to optimize patient care. In the last years, the introduction of immune checkpoint inhibitors is rapidly changing lung cancer management and therefore guidelines are essential to assist clinicians in such an evolving field. We reviewed the recommendations about the use of these immune checkpoint inhibitors in clinical practice guidelines issued by three scientific societies [European Society of Medical Oncology (ESMO); American Society of Clinical Oncology (ASCO); Italian Association of Medical Oncology (AIOM)] and one not-for-profit U.S. alliance [National Comprehensive Cancer Network (NCCN)] in order to underline their strengths and limitations. All the examined guidelines include some recommendations about use of immune checkpoint inhibitors in lung cancer patients. ASCO guidelines have a good methodologic background while their major limitation is their slow updating. NCCN guidelines, by contrast, are continuously updated but suffer from weak methodology and poor comparative tools. ESMO guidelines introduce a tool to assess the magnitude of clinical benefit for each recommended intervention that, although with some limitations, may improve clinical decision making. AIOM guidelines apply a robust methodology, but contain recommendations only on drugs reimbursed in Italy, thus limiting their applicability in different contexts. Clinical practice guidelines are useful tools that assist clinicians treating lung cancer patients with immune checkpoint inhibitors. Their use would improve homogeneity and appropriateness, even in this rapidly evolving field.