Enteric-type adenocarcinoma of the lung harbouring a novel KRAS Q22K mutation with concomitant KRAS polysomy: a case report.

This case describes a novel KRAS Q22K mutation with simultaneous KRAS polysomy in a patient with advanced, enteric-type, adenocarcinoma of the lung. Despite the administration of systemic chemotherapy, the disease underwent rapid progression and led to the patient's death in a short period of time. Such an aggressive clinical course suggests that, in this specific case, KRAS dependency was the major genetic driver of poor prognosis. Direct deoxy ribonucleic acid (DNA) sequencing of the KRAS gene allows for the detection of novel KRAS mutations, and it might be advocated in patients with advanced non-small cell lung cancer in view of the emerging role of KRAS as a potential therapeutic target.

Future options for ALK-positive non-small cell lung cancer.

Recent advances in the understanding of non-small cell lung cancer (NSCLC) biology have revealed a number of 'targetable' genetic alterations that underlie cancer growth and survival in specific patients subgroups. The anaplastic lymphoma kinase (ALK) gene rearrangement identifies a population of NSCLCs in whom dysregulation of ALK-tyrosine kinase (-TK) leads to uncontrolled proliferation of cancer cells, thus providing the basis for the therapeutic use of ALK-TK inhibitors (-TKIs) in ALK-rearranged (-positive) disease. Crizotinib was the first ALK-TKI to undergo clinical development in ALK-positive advanced NSCLC, in which it has been shown to greatly outperform the best available chemotherapy regimen in either second- or first-line setting. More recently, the novel second-generation ALK-TKI ceritinib has been shown to be highly active in either crizotinib-pretreated or -naïve population. Nevertheless, as mechanisms of resistance to crizotinib and ALK-TKIs in general are being progressively elucidated, the treatment landscape of ALK-positive NSCLC is expected to evolve rapidly. In the present review we will briefly discuss the current knowledge of ALK-positive advanced non-small cell lung cancer. Also, we will touch upon new developments on drugs/combination regimens aimed at inhibiting the ALK-TK, in an attempt to delineate how treatment of ALK-positive disease may change in the next future.

miRNAs and resistance to EGFR-TKIs in EGFR-mutant non-small cell lung cancer: beyond 'traditional mechanisms' of resistance.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) have dramatically changed the prognosis of advanced non-small cell lung cancers (NSCLCs) that harbour specific EGFR activating mutations. However, the efficacy of an EGFR-TKI is limited by the onset of acquired resistance, usually within one year, in virtually all treated patients. Moreover, a small percentage of EGFR-mutant NSCLCs do not respond to an EGFR-TKI, thus displaying primary resistance. At the present time, several mechanisms of either primary and acquired resistance have been elucidated, and new drugs are currently under preclinical and clinical development in order to overcome resistance to treatment. Nevertheless, there still remains much to be thoroughly investigated, as so far research has mainly focused on the role of proteincoding genes involved in resistance to EGFR-TKIs. On the other hand, in line with the data underscoring the relevance of non-coding RNAs in the pathogenesis of lung cancer and modulation of response to systemic therapies, microRNAs (miRNAs) have been supposed to play an important role in resistance to EGFR-TKIs. The aim of this review is to briefly summarise the existing relationship between miRNAs and resistance to EGFR-TKIs, and also focusing on the possible clinical applications of miRNAs in reverting and overcoming such resistance.

Non-coding RNAs in lung cancer.

The discovery that protein-coding genes represent less than 2% of all human genome, and the evidence that more than 90% of it is actively transcribed, changed the classical point of view of the central dogma of molecular biology, which was always based on the assumption that RNA functions mainly as an intermediate bridge between DNA sequences and protein synthesis machinery. Accumulating data indicates that non-coding RNAs are involved in different physiological processes, providing for the maintenance of cellular homeostasis. They are important regulators of gene expression, cellular differentiation, proliferation, migration, apoptosis, and stem cell maintenance. Alterations and disruptions of their expression or activity have increasingly been associated with pathological changes of cancer cells, this evidence and the prospect of using these molecules as diagnostic markers and therapeutic targets, make currently non-coding RNAs among the most relevant molecules in cancer research. In this paper we will provide an overview of non-coding RNA function and disruption in lung cancer biology, also focusing on their potential as diagnostic, prognostic and predictive biomarkers.

Clinical outcome with platinum-based chemotherapy in patients with advanced nonsquamous EGFR wild-type non-small-cell lung cancer segregated according to KRAS mutation status.

BACKGROUND: We hypothesized that KRAS mutations function as a marker of poor sensitivity to first-line platinum-based chemotherapy in patients with advanced nonsquamous EGFR wild-type (WT) non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Consecutive advanced nonsquamous EGFR WT NSCLCs treated at the Medical Oncology of Perugia with simultaneous assessment of KRAS mutation status were eligible. Anaplastic lymphoma kinase (ALK) gene status was known in roughly half of the patients who had KRAS WT. RESULTS: Two hundred four patients were included. Among them, the 77 individuals carrying a KRAS-mutant phenotype experienced a significantly inferior outcome in terms of response rate (P = .04), disease control rate (P = .05), and progression-free survival (PFS) (P = .05) compared with the EGFR WT/KRAS WT population. The association between KRAS mutation and shorter PFS remained statistically significant at multivariate analysis (hazard ratio [HR], 1.45). In addition, patients with KRAS mutations reported a significantly shorter overall survival (OS) compared with patients with EGFR WT/KRAS WT/ALK negativity (n = 64) (P = .02). Among patients with KRAS mutations, those harboring a mutation at codon 13 (n = 12) performed worse than those with a mutation at codon 12 (n = 62) in terms of both PFS and OS (P = .09 for both). CONCLUSION: KRAS mutation appears to negatively affect sensitivity to first-line platinum-based chemotherapy in patients with advanced nonsquamous EGFR WT NSCLC. Studies on larger case series are needed to address differences in clinical outcome according to the type of mutation.