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Simple Summary Mitotane is the only approved drug for the treatment of advanced adrenocortical carcinoma and for postoperative adjuvant therapy. It is known that mitotane destroys the adrenal cortex impairing steroidogenesis, although its exact molecular mechanism is still unclear. However, confounding factors affecting in vitro experiments could reduce the relevance of the studies. In this review, we explore in vitro studies on mitotane effects, highlighting how different experimental conditions might contribute to the controversial findings. On this basis, it may be necessary to re-evaluate the experiments taking into account their potential confounding factors such as cell strains, culture serum, lipoprotein concentration, and culture passages, which could hide important molecular results. As a consequence, the identification of novel pharmacological molecular pathways might be used in the future to implement personalized therapy, maximizing the benefit of mitotane treatment while minimizing its toxicity. Abstract Mitotane is the only approved drug for the treatment of advanced adrenocortical carcinoma and is increasingly used for postoperative adjuvant therapy. Mitotane action involves the deregulation of cytochromes P450 enzymes, depolarization of mitochondrial membranes, and accumulation of free cholesterol, leading to cell death. Although it is known that mitotane destroys the adrenal cortex and impairs steroidogenesis, its exact mechanism of action is still unclear. The most used cell models are H295-derived cell strains and SW13 cell lines. The diverging results obtained in presumably identical cell lines highlight the need for a stable in vitro model and/or a standard methodology to perform experiments on H295 strains. The presence of several enzymatic targets responsive to mitotane in mitochondria and mitochondria-associated membranes causes progressive alteration in mitochondrial structure when cells were exposed to mitotane. Confounding factors of culture affecting in vitro experiments could reduce the significance of any molecular mechanism identified in vitro. To ensure experimental reproducibility, particular care should be taken in the choice of culture conditions: aspects such as cell strains, culture serum, lipoproteins concentration, and culture passages should be carefully considered and explicated in the presentation of results. We aimed to review in vitro studies on mitotane effects, highlighting how different experimental conditions might contribute to the controversial findings. If the concerns pointed out in this review will be overcome, the new insights into mitotane mechanism of action observed in-vitro could allow the identification of novel pharmacological molecular pathways to be used to implement personalized therapy.

BCR-ABL1 fusion transcript is the minimal residual disease marker in chronic myeloid leukemia, 2% of patients show unusual breakpoints generating atypical transcripts, not quantifiable by standardized real-time PCR (RT&ndash, PCR). Response monitoring is performed by non-quantitative NESTED PCR, useless for evaluating patients&rsquo, molecular remission, excluding them from treatment-free-remission protocols. Droplet digital PCR (ddPCR) is highly sensitive technology, allowing an absolute quantification independent of standard curves. Based on this, we have developed assays able to evaluate the molecular response in atypical patients. We designed new ddPCR-based molecular assays able to quantify atypical BCR-ABL1 transcripts, with a detection limit of 0.001%, validated in a cohort of 65 RNA from 11 patients. Fifty samples were identified congruently by ddPCR and NESTED PCR (40 positives and 10 negatives for atypical BCR&ndash, ABL1 transcript), while 11 positive samples were detected only by ddPCR. Our results highlight ddPCR usefulness, primarily when the BCR&ndash, ABL1/ABL1 level is less than 1.5% and NESTED PCR results are often inaccurate. Furthermore, we identified 3 patients who maintained a deep molecular response for at least one year, who could be considered good candidates for treatment-free remission approaches. Here, we describe a new promising molecular approach, highly sensitive, to monitor atypical BCR&ndash, ABL1 patients, paving the foundation to include them in treatment-free remission protocols.

Myeloproliferative neoplasms are divided into essential thrombocythemia (ET), polycythemia vera (PV) and primary myelofibrosis (PMF). Although ruxolitinib was proven to be effective in reducing symptoms, patients rarely achieve complete molecular remission. Therefore, it is relevant to identify new therapeutic targets to improve the clinical outcome of patients. Bcl-xL protein, the long isoform encoded by alternative splicing of the Bcl-x gene, acts as an anti-apoptotic regulator. Our study investigated the role of Bcl-xL as a marker of severity of MPN and the possibility to target Bcl-xL in patients. 129 MPN patients and 21 healthy patients were enrolled in the study. We analysed Bcl-xL expression in leucocytes and in enriched CD34+ and CD235a+ cells. Furthermore, ABT-737, a Bcl-xL inhibitor, was tested in HEL cells and in leucocytes from MPN patients. Bcl-xL was found progressively over-expressed in cells from ET, PV and PMF patients, independently by JAK2 mutational status. Moreover, our data indicated that the combination of ABT-737 and ruxolitinib resulted in a significantly higher apoptotic rate than the individual drug. Our study suggests that Bcl-xL plays an important role in MPN independently from JAK2 V617F mutation. Furthermore, data demonstrate that targeting simultaneously JAK2 and Bcl-xL might represent an interesting new approach.

Background: Acute myeloid leukemia is a heterogeneous hematological disease, characterized by karyotypic and molecular alterations. Mutations in IDH2 have a role in diagnosis and as a minimal residue disease marker. Often the variant allele frequency during follow up is less than 20%, which represents the limit of detection of Sanger sequencing. Therefore, the development of sensitive methodologies to identify IDH2 mutations might help to monitor patients&rsquo, response to therapy. We compared three different methods to identify and monitor IDH2 mutations in patients&rsquo, specimens. Methods: Performances of PNA-PCR clamping, droplet digital PCR and Sanger for IDH2 status identification were evaluated and compared in 96 DNA patients&rsquo, specimens. Results: In contrast with Sanger sequencing, our results highlighted the concordance between PNA clamping and digital PCR. Furthermore, PNA-PCR clamping was able to detect more mutated DNA with respect to Sanger sequencing that showed several false negatives independently from the allelic frequency. Conclusions: We found that PNA-PCR clamping and digital PCR identified IDH2 mutations in DNA samples with comparable results in a percentage significantly higher compared to Sanger sequencing. PNA-PCR clamping can be used even in laboratories not equipped for sophisticated analyses, decreasing cost and time for IDH2 characterization.

Acute myeloid leukemia is a genetically heterogeneous disease characterized by the accumulation of mutations in hematopoietic progenitor cells. For its heterogeneity, prognostic markers are very useful for therapeutic choice. The most important prognostic markers are age, white blood cell count, chromosomal alterations and gene mutations. Recent works have studied the prognostic significance of WT1 polymorphisms and mutations, highlighting the role of SNP rs16754 as a positive prognostic factor in AML patients. Nevertheless, the data are still unclear. To investigate the role of WT1 rs16754 polymorphism in AML, we designed a new tool for the detection using PNA directed PCR Clamping technology. Our data were able to establish a correlation between SNP rs16754 and the clinical outcome. Our results support the hypothesis that rs16754 polymorphism is an independent positive prognostic molecular marker that could be useful for therapeutic choice. In view of this, we described a novel assay faster, more sensitive and cheaper than DNA sequencing. The assay allows evaluating WT1 rs16754 polymorphism in diagnostic routine to improve prognostic information faster and without over-costing for diagnostic laboratories.

Objectives Non-small-cell-lung-cancer (NSCLC) in young adults (≤45 years-old) accounts for a very small proportion, as this disease usually occurs in people at older age. The youthful NSCLC may constitute an entity with different clinical-pathologic characteristics, having predominance of adenocarcinoma histology and affecting mostly non-smoker subjects. However, without specific guidelines, it is currently considered, both clinically and biologically, as the same disease of the older counterpart, although differences have been documented. Materials and methods Using formalin-fixed paraffin embedded diagnostic tissues (FFPE), targeted next-generation sequencing (NGS) technology allowed to provide insight the mutational pattern of 46 oncogenes and tumor-suppressor genes in 26 young patients (Y). Two additional populations, including a FFPE series of aged counterpart (A: 29 patients) and a group of healthy young controls (C: 21, blood provided), were also investigated to compare NGS profiles. Results Clinical features of enrolled young patients harmonized with literature data, being most of patients women (58%), never-smokers (38%) and with adenocarcinoma histology (96%). C group was adopted to filter all the non-synonymous genetic variations (NS-GVs) not-associated with malignant overt disease. This skimmed selection mostly highlighted three genes: TP53, EGFR and KRAS. TP53 NS-GVs were numerically more numerous in younger, many involving specific annotated hotspot (R248, R273, G245, R249 and R282); the majority of EGFR NS-GVs was detected in young patients, with higher allelic frequency and mostly represented by exon 19 deletions. On the contrary, KRAS NS-GVs were mainly detected in aged population, with a prevalent compact pattern involving p.G12 position and associated with adenocarcinoma histology. Conclusion This retrospective study confirmed the feasibility of NGS approach for genetic characterization of NSCLC young adult patients, supporting the involvement of TP53, EGFR, and KRAS alterations in the early onset of NSCLC. Some of these GVs, or their pattern, may potentially contribute to customized targeted therapies.

// Valentina Monica 1 , Marco Lo Iacono 1 , Enrico Bracco 1 , Simone Busso 1 , Laura Di Blasio 2 , Luca Primo 2 , Barbara Peracino 3 , Mauro Papotti 1 , Giorgio Scagliotti 1 1 Department of Oncology, University of Torino, San Luigi Hospital, Orbassano, Torino, Italy 2 Department of Oncology, University of Torino, IRCCS Candiolo, Torino, Italy 3 Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, Orbassano, Torino, Italy Correspondence to: Valentina Monica, email: valentina.monica@unito.it Keywords: pemetrexed, dasatinib, malignant pleural mesothelioma, cell lines, thymidylate synthase Received: August 17, 2015 Accepted: June 16, 2016 Published: July 06, 2016 ABSTRACT Background: Thymidylate synthase (TS), one of the key enzymes for thymidine synthesis, is a target of pemetrexed (PEM), a key agent for the systemic therapy of malignant pleural mesothelioma (MPM) and its overexpression has been correlated to PEM-resistance. In MPM, experimental data report activation of the c-SRC tyrosine kinase suggesting it as a potential target to be further investigated. Results: MPM cell lines showed different sensitivity, being MSTO the most and REN the least sensitive to PEM. REN cells showed high levels of both TS and SRC: dasatinib inhibited SRC activation and suppressed TS protein expression, starting from 100 nM dose, blocking the PEM-induced up regulation of TS protein levels. Dasatinib treatment impaired cells migration, and both sequential and co-administration with PEM significantly increased apoptosis. Dasatinib pretreatment improved sensitivity to PEM, downregulated TS promoter activity and, in association with PEM, modulated the downstream PI3K-Akt-mTOR signaling. Cell lines and Methods: In three MPM cell lines (MPP89, REN and MSTO), the effects of c-SRC inhibition, in correlation with TS expression and PEM sensitivity, were evaluated. PEM and dasatinib, a SRC inhibitor, were administered as single agents, in combination or sequentially. Cell viability, apoptosis and migration, as well as TS expression and SRC activation have been assessed. Conclusions: These data indicate that dasatinib sensitizes mesothelioma cells to PEM through TS down-regulation.

Introduction Mucin-rich lung adenocarcinomas (ADCs), namely mucinous and colloid ADCs, are classified as ADC variants according to the World Health Organization 2015 classification. A correlation between morphological patterns and mutational status of these rare entities is not well established. Methods We investigated the mutational profile of mucin-rich lung ADCs in correlation with histopathological and morphological features with the goal of identifying biological tumor characteristics of potential prognostic and therapeutic interest. A series of 54 surgically resected primary mucinous lung ADC samples were retrospectively analyzed for clinicopathological characteristics and by targeted next-generation sequencing. Results Fifty cases were invasive mucinous ADCs (32 pure and 18 mixed) and four were colloid-predominant ADCs. Invasive mucinous ADC cases with a pure mucinous pattern were associated with a lower risk of vascular invasion ( p = 0.01), absence of signet ring cells ( p = 0.03), negative nodal status ( p = 0.006), and early clinical stage ( p = 0.02). The most prevalent mutations involved the Kirsten rat sarcoma viral oncogene homolog gene ( KRAS ) and tumor protein p53 gene ( TP53 ). Most mutations clustered in the mitogen-activated protein/protein kinase B pathway and in the p53/DNA repair pathway. A few uncommon epidermal growth factor receptor gene ( EGFR ) mutations were found. A correlation between a higher number of mutations and favorable clinical outcome was seen ( p Conclusions Our data showed that mucinous ADCs have peculiar pathological and molecular features that might suggest the need for a differentially tailored therapeutic approach compared with that to conventional lung ADC.

// Marco Lo Iacono 1, * , Consuelo Buttigliero 1, * , Valentina Monica 1, * , Enrico Bollito 1 , Diletta Garrou 1 , Susanna Cappia 1 , Ida Rapa 1 , Francesca Vignani 1 , Valentina Bertaglia 1 , Cristian Fiori 1 , Mauro Papotti 1 , Marco Volante 1 , Giorgio V. Scagliotti 1 , Francesco Porpiglia 1 , Marcello Tucci 1 1 University of Turin, Department of Oncology, Orbassano, Italy * All these Authors equally contributed to the experimental study Correspondence to: Consuelo Buttigliero, e-mail: consuelo.buttigliero@gmail.com Keywords: next generation sequencing, prostate cancer, precision medicine, genetic characterization, prognostic factors Received: November 17, 2015 Accepted: January 25, 2016 Published: February 12, 2016 ABSTRACT Purpose: Prostate cancer (PCa) has a highly heterogeneous outcome. Beyond Gleason Score, Prostate Serum Antigen and tumor stage, nowadays there are no biological prognostic factors to discriminate between indolent and aggressive tumors. The most common known genomic alterations are the TMPRSS-ETS translocation and mutations in the PI3K, MAPK pathways and in p53, RB and c-MYC genes. The aim of this retrospective study was to identify by next generation sequencing the most frequent genetic variations (GVs) in localized and locally advanced PCa underwent prostatectomy and to investigate their correlation with clinical-pathological variables and disease progression. Results: Identified non-synonymous GVs included TP53 p.P72R (78% of tumors), two CSFR1 SNPs, rs2066934 and rs2066933 (70%), KDR p.Q472H (67%), KIT p.M541L (28%), PIK3CA p.I391M (19%), MET p.V378I (10%) and FGFR3 p.F384L/p.F386L (8%). TP53 p.P72R, MET p.V378I and CSFR1 SNPs were significantly associated with the HI risk group, TP53 and MET variations with T≥T2c. FGFR3 p.F384L/p.F386L was correlated with T≤T2b. MET p.V378I mutation, detected in 20% of HI risk patients, was associated with early biochemical recurrence. Experimental design: Nucleic acids were obtained from tissue samples of 30 high (HI) and 30 low-intermediate (LM) risk patients, according to D’Amico criteria. Genomic DNA was explored with the Ion_AmpliSeq_Cancer_Hotspot_Panel_v.2 including 50 cancer-associated genes. GVs with allelic frequency (AF) ≥10%, affecting protein function or previously associated with cancer, were correlated with clinical-pathological variables. Conclusion: Our results confirm a complex mutational profile in PCa, supporting the involvement of TP53, MET, FGFR3, CSF1R GVs in tumor progression and aggressiveness.

Purpose Non–small-cell lung cancer (NSCLC) is a tumor in which only small improvements in clinical outcome have been achieved. The issue is critical for stage I patients for whom there are no available biomarkers that indicate which high-risk patients should receive adjuvant chemotherapy. We aimed to find DNA methylation markers that could be helpful in this regard. Patients and Methods A DNA methylation microarray that analyzes 450,000 CpG sites was used to study tumoral DNA obtained from 444 patients with NSCLC that included 237 stage I tumors. The prognostic DNA methylation markers were validated by a single-methylation pyrosequencing assay in an independent cohort of 143 patients with stage I NSCLC. Results Unsupervised clustering of the 10,000 most variable DNA methylation sites in the discovery cohort identified patients with high-risk stage I NSCLC who had shorter relapse-free survival (RFS; hazard ratio [HR], 2.35; 95% CI, 1.29 to 4.28; P = .004). The study in the validation cohort of the significant methylated sites from the discovery cohort found that hypermethylation of five genes was significantly associated with shorter RFS in stage I NSCLC: HIST1H4F, PCDHGB6, NPBWR1, ALX1, and HOXA9. A signature based on the number of hypermethylated events distinguished patients with high- and low-risk stage I NSCLC (HR, 3.24; 95% CI, 1.61 to 6.54; P = .001). Conclusion The DNA methylation signature of NSCLC affects the outcome of stage I patients, and it can be practically determined by user-friendly polymerase chain reaction assays. The analysis of the best DNA methylation biomarkers improved prognostic accuracy beyond standard staging.

c-Src is a tyrosine kinase involved in tumor proliferation, migration, and angiogenesis and has been shown to modulate the cytotoxicity following cisplatin-induced DNA damages. c-Src is frequently activated in non–small cell lung cancer (NSCLC) tissues and cell lines, but no preclinical data regarding the effects of the novel potent Src inhibitor, dasatinib (BMS-354825), in the modulation of cisplatin resistance are currently available. The present study reports that treatment with dasatinib completely abrogated Src phosphorylation in the majority of the NSCLC cell lines tested (n = 7), with modest effects on cell proliferation and survival. In five cell lines, a higher cytotoxicity was observed delivering cisplatin in combination with dasatinib: the most evident effects were found in the squamous H520 cells due to the effective block of cisplatin-induced Src phosphorylation. Moreover, dasatinib treatment significantly blocked cisplatin-induced transcription of a panel of DNA repair and synthesis genes. In addition, a real-time PCR analysis done on tumor and matched normal lung specimens from 44 surgically resected NSCLC patients showed that Src transcripts are significantly upregulated in 23% of cases. In conclusion, Src-directed therapeutic strategies could interfere with cisplatin resistance, possibly allowing to reduce cisplatin doses, thus improving its efficacy. The data of this study support further clinical studies aimed to evaluate the efficacy of Src-inhibiting agents in combination with cisplatin in the treatment of NSCLC. [Mol Cancer Ther 2009;8(11):3066–74]

7530 Background: The understanding of molecular pathogenesis of malignant pleural mesothelioma (MPM) has lagged behind other common malignancies. According to the COSMIC database the most frequentl...