Tracking MET de-addiction in lung cancer: A road towards the oncogenic target.

The discovery of druggable oncogenic drivers (i.e. EGFR and ALK), along with the introduction of comprehensive tumor genotyping techniques into the daily clinical practice define non-small-cell lung cancer (NSCLC) asa group of heterogeneous diseases, requiring a context-personalized clinico-therapeutical approach. Among the most investigated biomarkers, the MET proto-oncogene has been extensively demonstrated to play a crucial role throughout the lung oncogenesis, unbalancing the proliferation/apoptosis signaling and influencing the epithelial-mesenchymal transition and the invasive phenotype. Nevertheless, although different mechanisms eliciting the aberrant MET-associated oncogenic stimulus have been detected in lung cancer (such as gene amplification, increased gene copy number, mutations and MET/HGF overexpression), to date no clinically impactful results have been achieved with anti-MET tyrosine kinase inhibitors and monoclonal antibodies in the context of an unselected or MET enriched population. Recently, MET exon 14 splicing abnormalities have been identified asa potential oncogenic target in lung cancer, able to drive the activity of MET inhibitors in molecularly selected patients. In this paper, the major advancement and drawbacks of MET history in lung cancer are reviewed, underlying the renewed scientific euphoria related to the recent identification of MET exon 14 splicing variants asan actionable oncogenic target.

Current and developing therapies for the treatment of non-small cell lung cancer with ALK abnormalities: update and perspectives for clinical practice.

INTRODUCTION: The treatment of patients with ALK-rearranged non-small-cell lung cancer was completely revolutionized by the introduction of Crizotinib, a small molecule inhibiting ALK, MET and ROS1. Given that resistance occurs within approximately 12 months, in order to develop more potent inhibitors and to increase drug penetration to CNS, innovative ALK-inhibitors were developed. Second-generation ALK inhibitors Ceritinib (LDK378), Alectinib (CH5424802/RO5424802) and Brigatinib (AP26113) have shown significant clinical activity, and were rapidly approved by regulatory agencies. In addition, early clinical data demonstrated that 3rd generation ALK-inhibitors Lorlatinib (PF-06463922), Entrectinib (RxDx-101) and Ensartinib (X-398) provided promising advantages in terms of both clinical activity and safety. Areas covered: In this review, the efficacy and tolerability of Crizotinib for 1st and 2nd-line treatment, and the clinical and preclinical data that led to the development of innovative second and third generation ALK-inhibitors are described. Expert opinion: The better characterization of the mechanisms of resistance to Crizotinib led to the development of newest drugs, which are active both after Crizotinib failure and in patients naïve from ALK-inhibitors. Tumor characterization at disease progression will allow to further personalize the treatment by establishing optimal sequences, which represent tough challenges for the future research in this field of cancer treatment.

ALK gene copy number gains in non-small-cell lung cancer: prognostic impact and clinico-pathological correlations.

BACKGROUND: The correlation between ALK gene copy number gain (ALK-CNG) and prognosis in the context of advanced non-small-cell lung cancer (NSCLC) remains a controversial issue. This study aimed to evaluate the association among ALK-CNG according to Fluorescent In Situ Hybridization (FISH), clinical characteristics and survival in resectable and advanced NSCLC. METHODS: Clinical and pathological data of patients with resectable and advanced NSCLC were retrospectively collected. Tumor tissues were analyzed for ALK-CNG by FISH, and patients were divided in 3 groups/patterns on the basis of ALK signals: disomic [Pattern A], 3-7 signals [Pattern B], >7 signals [Pattern C]. The association between clinical and pathological features and ALK-CNG patterns was evaluated. Disease/progression-free and overall survival (DFS/PFS and OS) were estimated using the Kaplan-Meyer method. RESULTS: A number of 128 (76.6 %) out of the 167 eligible patients were evaluable for ALK-CNG, displaying pattern A, B and C in 71 (42.5 %), 42 (25.1 %) and 15 (9 %) patients, respectively. Gains in ALK-CNG appear to be more frequent in smokers/former smokers than in non-smokers (74.2 % versus 20.4 %, respectively, p = 0.03). Pattern A and C seem more frequently associated with higher T-stage (T3-4), while pattern B appears more represented in lower T-stage (T 1-2) (p = 0.06). No significant differences in survival rate were observed among the above groups. CONCLUSIONS: A high ALK-CNG pattern might be associated with smoking status and theoretically it might mirror genomic instability. The implications for prognosis should be prospectively investigated and validated in larger patients' series. TRIAL REGISTRATION: We confirm that all the study was performed in accordance with relevant guidelines and regulations and that all the protocol (part of a larger project MFAG 2013 N.14282) was approved by the local Ethics Committee of the Azienda Ospedaliera Universitaria Integrata of Verona on November 11st, 2014.

Comprehensive molecular portrait using next generation sequencing of resected intestinal-type gastric cancer patients dichotomized according to prognosis.

In this study, we evaluated whether the presence of genetic alterations detected by next generation sequencing may define outcome in a prognostically-selected and histology-restricted population of resected gastric cancer (RGC). Intestinal type RGC samples from 34 patients, including 21 best and 13 worst prognostic performers, were studied. Mutations in 50 cancer-associated genes were evaluated. A significant difference between good and poor prognosis was found according to clinico-pathologic factors. The most commonly mutated genes in the whole population were PIK3CA (29.4%), KRAS (26.5%), TP53 (26.5%) MET (8.8%), SMAD4 (8.8%) and STK11 (8.8%). Multiple gene mutations were found in 14/21 (67%) patients with good prognosis, and 3/13 (23%) in the poor prognosis group. A single gene alteration was found in 5/21 (24%) good and 6/13 (46%) poor prognosis patients. No mutation was found in 2/21 (9.5%) and 4/13 (31%) of these groups, respectively. In the overall series, ß-catenin expression was the highest (82.4%), followed by E-Cadherin (76.5%) and FHIT (52.9%). The good prognosis group was characterized by a high mutation rate and microsatellite instability. Our proof-of-principle study demonstrates the feasibility of a molecular profiling approach with the aim to identify potentially druggable pathways and drive the development of customized therapies for RGC.

Extra-nodal extension of sentinel lymph node metastasis is a marker of poor prognosis in breast cancer patients: A systematic review and an exploratory meta-analysis.

Invasive breast cancer is the most common malignancy in women. Its most common site of metastasis is represented by the lymph nodes of axilla, and the sentinel lymph node (SLN) is the first station of nodal metastasis. Axillary SLN biopsy accurately predicts axillary lymph node status and has been accepted as standard of care for nodal staging in breast cancer. To date, the morphologic aspects of SLN metastasis have not been considered by the oncologic staging system. Extranodal extension (ENE) of nodal metastasis, defined as extension of neoplastic cells through the nodal capsule into the peri-nodal adipose tissue, has recently emerged as an important prognostic factor in several types of malignancies. It has also been considered as a possible predictor of non-sentinel node tumor burden in SLN-positive breast cancer patients. We sought out to clarify the prognostic role of ENE in SLN-positive breast cancer patients in terms of overall and disease-free survival by conducting a systematic review and meta-analysis. Among 172 screened articles, 5 were eligible for the meta-analysis; they globally include 624 patients (163 ENE+ and 461 ENE-) with a median follow-up of 58 months. ENE was associated with a higher risk of both mortality (RR = 2.51; 95% CI: 1.66-3.79, p < 0.0001, I(2) = 0%) and recurrence of disease (RR = 2.07, 95% CI: 1.38-3.10, p < 0.0001, I(2) = 0%). These findings recommend the consideration of ENE from the gross sampling to the histopathological evaluation, in perspectives to be validated and included in the oncologic staging.

Tubulin inhibitors in non-small cell lung cancer: looking back and forward.

INTRODUCTION: Although the advent of target therapy for lung cancer has brought about outstanding results, this benefit is confined to a subgroup of molecularly selected patients, whereas for most non-small cell lung cancer (NSCLC) patients, chemotherapy still represents the milestone of treatment. Since their introduction into clinics, microtubule targeting agents (MTA), including vinca alkaloids and taxanes, have been extensively used for NSCLC in different settings and combinations. AREAS COVERED: In this review, MTA are classified according to their mechanism of action, with a focus on the most common mechanisms of resistance. Moreover, an overview of the most remarkable clinical data regarding MTA in adjuvant, neoadjuvant and advanced setting is provided. Finally, the novel mitotic kinases inhibitors are described according to their different mechanism of action and clinical activity compared to MTA. EXPERT OPINION: Unfortunately, the awaited benefit deriving from the actually available chemotherapeutic regimens for advanced NSCLC has reached a plateau. In this scenario, the identification of reliable predictive biomarkers represents a major challenge. Moreover, different schedules for MTA administration are currently under investigation, such as the combination of MTA with other drugs able to bypass the resistance derived from the 'mitotic slippage' and the use of metronomic administration of spindle poisons with anti-angiogenic or immunomodulatory agents.