Lung cancer is the most common malignancy and cause of cancer deaths worldwide, owing to the dismal prognosis for most affected patients. Phosphatase and tensin homolog deleted in chromosome 10 (PTEN) acts as a powerful tumor suppressor gene and even partial reduction of its levels increases cancer susceptibility. While the most validated anti-oncogenic duty of PTEN is the negative regulation of the PI3K/mTOR/Akt oncogenic signaling pathway, further tumor suppressor functions, such as chromosomal integrity and DNA repair have been reported. PTEN protein loss is a frequent event in lung cancer, but genetic alterations are not equally detected. It has been demonstrated that its expression is regulated at multiple genetic and epigenetic levels and deeper delineation of these mechanisms might provide fertile ground for upgrading lung cancer therapeutics. Today, PTEN expression is usually determined by immunohistochemistry and low protein levels have been associated with decreased survival in lung cancer. Moreover, available data involve PTEN mutations and loss of activity with resistance to targeted treatments and immunotherapy. This review discusses the current knowledge about PTEN status in lung cancer, highlighting the prevalence of its alterations in the disease, the regulatory mechanisms and the implications of PTEN on available treatment options.

Lung cancer remains the leading cause of cancer‐related death worldwide. Affected patients frequently experience debilitating disease‐related symptoms, including dyspnea, cough, fatigue, anxiety, depression, insomnia, and pain, despite the progresses achieved in term of treatment efficacy. Physical activity and exercise are nonpharmacological interventions that have been shown to improve fatigue, quality of life, cardiorespiratory fitness, pulmonary function, muscle mass and strength, and psychological status in patients with lung cancer. Moreover, physical fitness levels, especially cardiorespiratory endurance and muscular strength, are demonstrated to be independent predictors of survival. Nevertheless, patients with lung cancer frequently present insufficient levels of physical activity and exercise, and these may contribute to quality of life impairment, reduction in functional capacity with skeletal muscle atrophy or weakness, and worsening of symptoms, particularly dyspnea. The molecular bases underlying the potential impact of exercise on the fitness and treatment outcome of patients with lung cancer are still elusive. Counteracting specific cancer cells’ acquired capabilities (hallmarks of cancer), together with preventing treatment‐induced adverse events, represent main candidate mechanisms. To date, the potential impact of physical activity and exercise in lung cancer remains to be fully appreciated, and no specific exercise guidelines for patients with lung cancer are available. In this article, we perform an in‐depth review of the evidence supporting physical activity and exercise in lung cancer and suggest that integrating this kind of intervention within the framework of a global, multidimensional approach, taking into account also nutritional and psychological aspects, might be the most effective strategy. Implications for Practice Although growing evidence supports the safety and efficacy of exercise in lung cancer, both after surgery and during and after medical treatments, most patients are insufficiently active or sedentary. Engaging in exercise programs is particularly arduous for patients with lung cancer, mainly because of a series of physical and psychosocial disease‐related barriers (including the smoking stigma). A continuous collaboration among oncologists and cancer exercise specialists is urgently needed in order to develop tailored programs based on patients’ needs, preferences, and physical and psychological status. In this regard, benefit of exercise appears to be potentially enhanced when administered as a multidimensional, comprehensive approach to patients’ well‐being.

Genomic alterations affecting components of the mechanistic target of rapamycin (mTOR) pathway are found rather frequently in cancers, suggesting that aberrant pathway activity is implicated in oncogenesis of different tumor types. mTOR functions as the core catalytic kinase of two distinct complexes, mTOR complex 1 (mTORC1) and 2 (mTORC2), which control numerous vital cellular processes. There is growing evidence indicating that Rictor, an essential subunit of the mTORC2 complex, is inappropriately overexpressed across numerous cancer types and this is associated with poor survival. To date, the candidate mechanisms responsible for aberrant Rictor expression described in cancer are two: i) gene amplification and ii) epigenetic regulation, mainly by microRNAs. Moreover, different mTOR-independent Rictor-containing complexes with oncogenic role have been documented, revealing alternative routes of Rictor-driven tumorigenesis, but simultaneously, paving the way for identifying novel biomarkers and therapeutic targets. Here, we review the main preclinical and clinical data regarding the role of Rictor in carcinogenesis and metastatic behavior as well as the potentiality of its alteration as a target.

Abstract:The MET proto-oncogene plays crucial roles in cell growth and proliferation, survival and apoptosis, epithelial-mesenchymal transition (EMT) and invasion, potentially conditioning the development and progression of the carcinogenesis process. The MET-associated aberrant signaling could be triggered by a variety of mechanisms, such as mutations, gene amplification, increased gene copy number and Met/HGF protein expression. Among the various MET alterations, MET exon 14 splicing abnormalities, causing the loss of the Met juxtamembrane (JM) domain, recently emerged as a new potential oncogenic driver and have been identified and validated across different cancer and histology subtypes. Moreover, this aberration was found to be mutually exclusive with other recognized drivers, thus strongly nominating its potential oncogenic role. Recently, the clinical activity of anti-Met-targeted therapy was demonstrated particularly in patients harboring MET exon 14 skipping lung cancer, resulting in a renewed enthusiasm to further test MET precision therapy in prospective trials. In this review, the key preclinical and clinical data regarding MET exon 14 skipping splicing variants as an actionable genomic aberration in cancer are described, and the perspectives deriving from the validation of such alteration as a potential target, which may further allow driving the therapeutic approach in this molecularly selected patients' subgroup, are explored.

In non-small-cell lung cancer (NSCLC) the recent introduction of immunotherapy in daily clinical practice produced a wave of enthusiasm, however, this was rapidly moderated by the evidence that only some patients could experience a relevant clinical benefit. Therefore, a great effort from the scientific community has been dedicated to the identification and validation of reliable biomarkers able to drive the activity of immunotherapeutic agents. Areas covered: This analysis aims to review the main findings about predictive biomarkers for immunotherapy in lung cancer, retracing the history of PD-L1 and focusing on a series of innovative candidates, such as mutational load, immune cell populations and microbiome. Expert commentary: Considering the complexity of the immune system-cancer interactions, the idea of identifying a single biomarker able to drive the activity of different immunotherapeutic agents alone, borrowing the idea of targeted therapy, is likely to represent an unrealistic objective. Nevertheless, the identification of those factors either positively or negatively affecting the response is mandatory in order to recruit the appropriate patients, but also to deeply understand the mechanisms of immune response and improve the clinical benefit deriving from these agents in monotherapy or in a biologically-rationale combination.