Individualized therapy in non-small-cell lung cancer: future versus current clinical practice

Differential Radiation Sensitivity in p53 Wild-Type and p53-Deficient Tumor Cells Associated with Senescence but not Apoptosis or (Nonprotective) Autophagy

Studies of radiation interaction with tumor cells often focus on apoptosis as an end point; however, clinically relevant doses of radiation also promote autophagy and senescence. Moreover, functional p53 has frequently been implicated in contributing to radiation sensitivity through the facilitation of apoptosis. To address the involvement of apoptosis, autophagy, senescence and p53 status in the response to radiation, the current studies utilized isogenic H460 non-small cell lung cancer cells that were either p53-wild type (H460wt) or null (H460crp53). As anticipated, radiosensitivity was higher in the H460wt cells than in the H460crp53 cell line; however, this differential radiation sensitivity did not appear to be a consequence of apoptosis. Furthermore, radiosensitivity did not appear to be reduced in association with the promotion of autophagy, as autophagy was markedly higher in the H460wt cells. Despite radiosensitization by chloroquine in the H460wt cells, the radiation-induced autophagy proved to be essentially nonprotective, as inhibition of autophagy via 3-methyl adenine (3-MA), bafilomycin A1 or ATG5 silencing failed to alter radiation sensitivity or promote apoptosis in either the H460wt or H460crp53 cells. Radiosensitivity appeared to be most closely associated with senescence, which occurred earlier and to a greater extent in the H460wt cells. This finding is consistent with the in-depth proteomics analysis on the secretomes from the H460wt and H460crp53 cells (with or without radiation exposure) that showed no significant association with radioresistance-related proteins, whereas several senescence-associated secretory phenotype (SASP) factors were upregulated in H460wt cells relative to H460crp53 cells. Taken together, these findings indicate that senescence, rather than apoptosis, plays a central role in determination of radiosensitivity; furthermore, autophagy is likely to have minimal influence on radiosensitivity under conditions where autophagy takes the nonprotective form.

H19 contributes to poor clinical features in NSCLC patients and leads to enhanced invasion in A549 cells through regulating miRNA-203-mediated epithelial-mesenchymal transition

Recent studies have demonstrated that the overexpression of H19 may contribute towards development of tumorigenesis in various types of cancer. To investigate the role of H19 in the development of non-small cell lung cancer (NSCLC), 76 NSCLC tissues samples and their adjacent normal tissue samples were collected. Expression level of H19, and its association with clinicopathological features and overall survival was analyzed. It was found that compared with normal adjacent tissues, H19 expression was elevated in NSCLC tissues along with a decreased miR-203 expression level. It was also found that patients who were in advanced clinical stages had a higher H19 and a lower miR-203 expression compared to normal tissues. The overall survival time of patients with higher H19 expression was shorter compared with the lower H19 expression group. Upregulation of A549 enhanced cell proliferation and promoted invasion. Overexpression of H19 stimulated the epithelial-mesenchymal transition (EMT) process in lung cancer cells and demonstrated typical morphological characteristics of EMT. The level of mesenchymal marker protein, such as Vimentin and SNAI1 increased; while CDH1 protein level decreased. Also, H19 negatively regulated miR-203. Inhibition of H19 attenuated miR-203 induced EMT process. Upregulation of H19 contributes to poor clinical features in patients with NSCLC, induces occurrence of EMT, promotes proliferation and stimulates cell invasion in NSCLC cell line through regulating miRNA-203 mediated EMT.

Impact of DLK1-DIO3 imprinted cluster hypomethylation in smoker patients with lung cancer

DNA methylation is important for gene expression and genome stability, and its disruption is thought to play a key role in the initiation and progression of cancer and other diseases. The DLK1-DIO3 cluster has been shown to be imprinted in humans, and some of its components are relevant to diverse pathological processes. The purpose of this study was to assess the methylation patterns of the DLK1-DIO3 cluster in patients with lung cancer to study its relevance in the pathogenesis of this disease. We found a characteristic methylation pattern of this cluster in smoking associated lung cancer, as compared to normal lung tissue. This methylation profile is not patent however in lung cancer of never smokers nor in lung tissue of COPD patients. We found 3 deregulated protein-coding genes at this locus: one was hypermethylated (DIO3) and two were hypomethylated (DLK1 and RTL1). Statistically significant differences were also detected in two different families of SNORDs, two miRNA clusters and four lncRNAs (MEG3, MEG8, MEG9 and LINC00524). These findings were validated using data from the cancer genome atlas (TCGA) database. We have then showed an inverse correlation between DNA methylation and expression levels in 5 randomly selected genes. Several targets of miRNAs included in the DLK1-DIO3 cluster have been experimentally verified as tumor suppressors. All of these results suggest that the dysmethylation of the imprinted DLK1-DIO3 cluster could have a relevant role in the pathogenesis of lung cancer in current and former smokers and may be used for diagnostic and/or therapeutic purposes.

Molecular testing of different cytologic preparations in patients with advanced lung adenocarcinoma: which yields the best results?

INTRODUCTION

This study constitutes the first systematic comparison of molecular results between different cytology preparations in patients with lung adenocarcinoma undergoing testing for EGFR, KRAS, and BRAF mutations.

MATERIALS AND METHODS

115 archival cytology preparations (direct smears, ThinPrep preparations [TP], and cell blocks [CB]) from lung adenocarcinomas with known EGFR, KRAS, or BRAF mutations were tested and compared with clinical testing results. Results were compared between preparations and analyzed in relation to tumor purity and tumor cell content.

RESULTS

82 (77%) of 106 informative cases were concordant with clinical testing results. There was no significant difference in the concordance rate between CB, TP, air-dried smears, or alcohol-fixed smears (P = 0.3803), nor between preparations with <25%, 25% to 50%, or >50% tumor purity (P = 0.1147). Concordance rates were lower in preparations with ≤100 tumor cells (P = 0.0002).

CONCLUSIONS

Smears, TP, and CB are all valid substrates for molecular testing. Although tumor purity did not significantly affect results, low tumor content showed poorer performance. Recording tumor purity and content is recommended.

Osthole induces lung cancer cell apoptosis through inhibition of inhibitor of apoptosis family proteins

In the present study, we investigated the effects and mechanisms of Osthole on the apoptosis of non-small cell lung cancer (NSCLC) cells and its synergistic effect with Embelin. Our results revealed that treatment with both Osthole and Embelin inhibited cell proliferation. Notably, combination treatment of Osthole and Embelin inhibited cell proliferation more significantly compared with monotherapy. In addition, morphological analysis and Annexin V/propidium iodide analysis revealed that the combination of Osthole and Embelin enhanced their effect on cell apoptosis. We further examined the effect of Osthole on the expression of inhibitor of apoptosis protein (IAP) family proteins. That treatment of A549 lung cancer cells with various concentrations of Osthole was observed to decrease the protein expression of X-chromosome-encoded IAP, c-IAP1, c-IAP2 and Survivin, and increase Smac expression in a dose-dependent manner. Furthermore, it was noted that Osthole or Embelin alone increased the expression of BAX, caspase-3, caspase-9, cleaved caspase-3 and cleaved caspase-9, and decreased Bcl-2 levels following treatment. Osthole and Embelin combination treatment had a synergistic effect on the regulation of these proteins. In conclusion, our study demonstrated that Osthole inhibited proliferation and induced the apoptosis of lung cancer cells via IAP family proteins in a dose-dependent manner. Osthole enhances the antitumor effect of Embelin, indicating that combination of Osthole and Embelin has potential clinical significance in the treatment of NSCLC.

Current and future targeted therapies for non-small-cell lung cancers with aberrant EGF receptors

Expression of the EGF receptors (EGFRs) is abnormally high in many types of cancer, including 25% of lung cancers. Successful treatments target mutations in the EGFR tyrosine kinase domain with EGFR tyrosine kinase inhibitors (TKIs). However, almost all patients develop resistance to this treatment, and acquired resistance to first-generation TKI has prompted the clinical development of a second generation of EGFR TKI. Because of the development of resistance to treatment of TKIs, there is a need to collect genomic information about EGFR levels in non-small-cell lung cancer patients. Herein, we focus on current molecular targets that have therapies available as well as other targets for which therapies will be available in the near future.

Advanced squamous lung carcinoma in a patient experiencing long-term survival following repeated responses to gemcitabine and cisplatin chemotherapy: A case report

The cisplatin and gemcitabine regimen is one of the most effective regimens against advanced non-small-cell lung cancer. However, tumors that are initially sensitive to chemotherapy treatment may acquire drug resistance. Excision repair cross complementation 1 gene (ERCC1) is involved in the repair of DNA damage caused by cisplatin, and ribonucleotide reductase M1 subunit (RRM1) is associated with gemcitabine resistance in tumor cells. The current study reports the case of a patient with advanced squamous cell lung carcinoma exhibiting low ERCC1 and RRM1 expression levels, who experienced long-term survival following repeated responses to gemcitabine and cisplatin chemotherapy. This case indicates that selected patients may benefit from multiple courses of gemcitabine and cisplatin chemotherapy, and the sustained clinical benefits suggest that further investigation into individualized therapy is merited.

Aerosol azacytidine inhibits orthotopic lung cancers in mice through Its DNA demethylation and gene reactivation effects

We devised an aerosol based demethylation therapy to achieve therapeutic efficacy in premalignant or in situ lesions of lung cancer, without systemic toxicity. Optimum regimens of aerosolized azacytidine (Aza) were designed and used in orthotopic human non-small cell lung cancer xenograft models. The therapeutic efficacy and toxicity of aerosol Aza were compared with intravenously administered Aza. We observed that 80% of the droplets of the aerosol Aza measured ∼0.1–5 microns, which resulted in deposition in the lower bronchial airways. An animal model that phenocopies field carcinogeneisis in humans was developed by intratracheal inoculation of the human lung cancer cells in mice, thus resulting in their distribution throughout the entire airway space. Aerosolized Aza significantly prolonged the survival of mice bearing endo-bronchial lung tumors. The aerosol treatment did not cause any detectable lung toxicity or systemic toxicity. A pre-pharmacokinetic study in mice demonstrated that lung deposition of aerosolized Aza was significantly higher than the intravenous route. Lung tumors were resected after aerosol treatment and the methylation levels of 24 promoters of tumor-suppresser genes related to lung cancer were analyzed. Aerosol Aza significantly reduced the methylation level in 9 of these promoters and reexpressed several genes tested. In conclusion, aerosol Aza at non-cytotoxic doses appears to be effective and results in DNA demethylation and tumor suppressor gene re-expression. The therapeutic index of aerosol Aza is >100-fold higher than that of intravenous Aza. These results provide a preclinical rationale for a phase I clinical trial of aerosol Aza to be initiated at our Institution.

MicroRNA-dependent regulation of transcription in non-small cell lung cancer

Squamous cell lung cancer (SCC) and adenocarcinoma are the most common histological subtypes of non-small cell lung cancer (NSCLC), and have been traditionally managed in the clinic as a single entity. Increasing evidence, however, illustrates the biological diversity of these two histological subgroups of lung cancer, and supports the need to improve our understanding of the molecular basis beyond the different phenotypes if we aim to develop more specific and individualized targeted therapy. The purpose of this study was to identify microRNA (miRNA)-dependent transcriptional regulation differences between SCC and adenocarcinoma histological lung cancer subtypes. In this work, paired miRNA (667 miRNAs by TaqMan Low Density Arrays (TLDA)) and mRNA profiling (Whole Genome 44 K array G112A, Agilent) was performed in tumor samples of 44 NSCLC patients. Nine miRNAs and 56 mRNAs were found to be differentially expressed in SCC versus adenocarcinoma samples. Eleven of these 56 mRNA were predicted as targets of the miRNAs identified to be differently expressed in these two histological conditions. Of them, 6 miRNAs (miR-149, miR-205, miR-375, miR-378, miR-422a and miR-708) and 9 target genes (CEACAM6, CGN, CLDN3, ABCC3, MLPH, ACSL5, TMEM45B, MUC1) were validated by quantitative PCR in an independent cohort of 41 lung cancer patients. Furthermore, the inverse correlation between mRNAs and microRNAs expression was also validated. These results suggest miRNA-dependent transcriptional regulation differences play an important role in determining key hallmarks of NSCLC, and may provide new biomarkers for personalized treatment strategies.

Secreted frizzled related proteins: Implications in cancers

The Wnt (wingless-type) signaling pathway plays an important role in embryonic development, tissue homeostasis, and tumor progression becaluse of its effect on cell proliferation, migration, and differentiation. Secreted frizzled-related proteins (SFRPs) are extracellular inhibitors of Wnt signaling that act by binding directly to Wnt ligands or to Frizzled receptors. In recent years, aberrant expression of SFRPs has been reported to be associated with numerous cancers. As gene expression of SFRP members is often lost through promoter hypermethylation, inhibition of methylation through the use of epigenetic modifying agents could renew the expression of SFRP members and further antagonize deleterious Wnt signaling. Several reports have described epigenetic silencing of these Wnt signaling antagonists in various human cancers, suggesting their possible role as tumor suppressors. SFRP family members thus come across as potential tools in combating Wnt-driven tumorigenesis. However, little is known about SFRP family members and their role in different cancers. This review comprehensively covers all the available information on the role of SFRP molecules in various human cancers.

TMEM158 and FBLP1 as novel marker genes of cisplatin sensitivity in non-small cell lung cancer cells

Even after development of molecular targeting therapies, platinum-based chemotherapy is still a standard care for treatment of locally advanced non-small cell lung cancer (NSCLC). So far, critical molecular markers capable to predict the therapeutic response in NSCLC patients remain undetermined. We here attempted to identify novel biomarker genes for cisplatin (CDDP) for a tailored therapy. Initial screening to explorer association of IC(50) values of CDDP obtained by MTT assay and gene expression levels measured with oligonucleotide microarray and real-time RT-PCR provided 6 candidate genes, namely, NUBPL, C9orf30, ZNF12, TMEM158, GSK3B, and FBLP1 using 9 lung cancer cells consisting of 3 small and 6 NSCLC cells. These 6 genes together with 5 reported biomarkers, i.e., GSTP1, ERCC1, BRCA1, FRAP1, and RRM1, were subjected to a linear regression analysis using 12 NSCLC cell lines including 6 additional NSCLC cells: only FBLP1 and TMEM158 genes showed positive associations with statistical significances (P = .016 and .026, respectively). The biological significance of these genes was explored by in vitro experiments: Knockdown experiments in PC-9/CDDP cells revealed that the reduced expression of TMEM158 significantly decreased the chemo-resistance against CDDP (P <.0001), while 2 transformants of PC-6 cells stably over-expressing FBLP1 resulted in an enhanced resistance to CDDP (P = .004 and P = .001). Furthermore, a stepwise multiple regression analysis demonstrated the best prediction formula could be fixed when we used expression data of TMEM158 and FBLP1 (R(2) = 0.755, P = .0018). TMEM158 and FBLP1 may be powerful predictive biomarkers for CDDP therapy in NSCLC.

Soluble Human Epidermal Growth Factor Receptor 2 (sHER2) as a Potential Risk Assessment, Screening, and Diagnostic Biomarker of Lung Adenocarcinoma

Lung cancer is the leading cause of cancer-related death in the United States. Here, we evaluated the potential clinical utility of soluble human epidermal growth factor receptor 2 (sHER2) for the risk assessment, screening, and diagnosis of non-small cell lung cancer (NSCLC) using an unmatched case-control study design. Serum sHER2 concentrations were measured by immunoassay in 244 primary NSCLC cases and 218 healthy controls. Wilcoxon rank-sum tests, logistic regression models, and receiver operating characteristic plots were used to assess whether sHER2 is associated with lung cancer. Median serum sHER2 concentrations are higher in patients with adenocarcinoma than squamous cell carcinoma regardless of gender, and sHER2 is a weak, independent biomarker of adenocarcinoma, but not of squamous cell carcinoma, adjusted for age and gender. The age-adjusted relative risk (odds) of adenocarcinoma is 3.95 (95% CI: 1.22, 12.81) and 7.93 (95% CI: 2.26, 27.82) greater for women and men with high sHER2 concentrations (≥6.60 ng/mL) vs. low sHER2 concentrations (≤1.85 ng/mL), respectively. When adjusted for each other, sHER2, age, and gender discern healthy controls from patients with primary adenocarcinomas of the lung with 85.9% accuracy. We conclude that even though serum sHER2 is not a strong, stand-alone discriminatory biomarker of adenocarcinoma, sHER2 may be a useful, independent covariate in multivariate risk assessment, screening, and diagnostic models of lung cancer.

Interferon (alpha, beta and omega) receptor 2 is a prognostic biomarker for lung cancer

OBJECTIVES

It has been reported that the type I interferon receptor subunit, interferon (alpha, beta and omega) receptor 2 (IFNAR2), is overexpressed in several malignancies, primarily adenocarcinomas (ADCs); however, the biological significance of IFNAR2 in human lung cancer has not yet been studied.

METHODS

Immunohistochemical analysis of 113 surgically resected lung specimens was performed, and the results were evaluated in association with clinical variables, including survival. Serum concentrations of IFNAR2 were also determined by an enzyme-linked immunosorbent assay in 157 lung cancer patients and 164 healthy volunteers.

RESULTS

IFNAR2 overexpression was observed in all histological types of lung cancer examined. Furthermore, strong IFNAR2 expression was associated with shorter progression-free survival (PFS) and overall survival (OS) (p < 0.0001 and p = 0.0110, respectively) in non-small cell lung cancer patients. Multivariate analyses confirmed its independent prognostic value for PFS and OS (p < 0.0001 and p = 0.0222, respectively). IFNAR2 serum levels were also significantly higher in lung cancer patients than in healthy volunteers (p < 0.0001).

CONCLUSIONS

IFNAR2 overexpression was observed in various histological types of lung cancer, and appears to be associated with lung cancers that behave aggressively. The results of this study strongly support the potential of IFNAR2 to be a prognostic biomarker for lung cancer.

Validation of cofilin-1 as a biomarker in non-small cell lung cancer: application of quantitative method in a retrospective cohort

PURPOSE

Cofilin is a cytoskeletal protein whose overexpression has been associated with aggressiveness in several types of malignancies. Here, we established and optimized a simple semi-quantitative immunohistochemistry (SQ-IHC) method for cofilin quantification in tumor biopsies, and applied it in a retrospective cohort of NSCLC patients aiming at validating the use of cofilin-1 as a prognostic biomarker.

METHODS

The SQ-IHC method for cofilin-1 quantification was established and applied in a NSCLC cohort. An archival collection of biopsies from 50 patients with clinicopathological information and 5 years follow-up was accessed. Association between cofilin-1 immunocontent and clinical outcome was assessed using standard Kaplan-Meier mortality curves and the log-rank test. To evaluate the robustness of our findings, three different partitional clustering strategies were used to stratify patients into two groups according to the biomarker expression level (hierarchical clustering, Kmeans and median cutoff).

RESULTS

In all the three different partitional clustering we used, survival analysis showed that patient with high cofilin-1 immunocontent had a lower overall survival rate (P < 0.05), and could be used to discriminate between good and bad prognosis. No other correlation was found when the variables age, sex or histological type were tested in association with patients outcome or with cofilin immunocontent.

CONCLUSIONS

Our method showed good sensitivity/specificity to indicate the outcome of patients according to their cofilin immunocontent in biological samples. Its application in a retrospective cohort and the results presented here are an important step toward the validation process of cofilin-1 as a prognostic biomarker.

ERCC1 protein as a guide for individualized therapy of late-stage advanced non-small cell lung cancer

Excision repair cross-complementation group 1 (ERCC1) protein has been associated with cisplatin resistance. The objective of this study was to investigate the correlation between ERCC1 protein levels and the therapeutic effect of individualized therapy in advanced non-small cell lung cancer (NSCLC). A total of 190 advanced NSCLC patients were included in this study. Patients were randomized into either the individualized therapy group or the standard therapy group at a ratio of 2:1. Patients in the standard therapy group were treated with either gemcitabine plus cisplatin or vinorelbine plus cisplatin. The expression of ERCC1 protein in lung cancer tissues of patients from the individualized therapy group was detected with immunohistochemistry. Patients with low ERCC1 levels received either gemcitabine plus cisplatin or vinorelbine plus cisplatin, and patients with high levels received gemcitabine plus vinorelbine. The main outcome assessments were response rate (RR), overall survival (OS) and time to progression (TTP). Follow-up data were recorded until September 30, 2010. RR, 1-year survival rate and TTP were not statistically significant. The median survival time was 10.10 months in the standard therapy group (95% CI 8.48-11.92) and 13.59 months in the individualized therapy group (95% CI 11.86-14.74). The difference in median survival time was significantly different between these groups (P=0.036). The median survival time was longer in the individualized group compared to the standard therapy group. ERCC1 protein expression in advanced NSCLC patients, however, was not significantly correlated with RR, OS and TTP in the individualized therapy group. Therefore, this study suggests that ERCC1 protein levels should be assessed in combination with additional biomarkers to determine an optimal index for individualized therapy in advanced NSCLC patients.

Genomic medicine in non-small cell lung cancer: paving the path to personalized care

Lung cancer is the commonest cause of cancer-related mortality and non-small cell lung cancer (NSCLC) accounts for 80% of all lung cancer. The prognosis of NSCLC remains poor across all stages, despite advances in staging techniques and treatments. The findings of recent high-throughput mRNA microarray studies have shown potential in refining current NSCLC diagnosis, classification, prognosis and treatment paradigms. Emerging microarray studies of microRNA, DNA copy number and methylation profiles are also providing novel insights into the biology of NSCLC. Currently there are several challenges, such as the reproducibility and cost of microarray platforms that will need to be addressed prior to the implementation of these genomic technologies to routine thoracic oncology practice. In addition, genomic tests (such as prognosis and prediction gene expression signatures) will need to be validated in well designed prospective studies that aim to answer clinically relevant questions. If successful, the integration of microarray-based genomic information with existing clinicopathological models may enhance the ability of clinicians to match the most effective treatment to an individual patient. Such a strategy may improve survival and reduce treatment-related morbidity in NSCLC patients.

Tailoring tyrosine kinase inhibitors to fit the lung cancer genome

Tyrosine kinase inhibitors (TKIs) have been in use as cancer therapeutics for nearly a decade, and their utility in targeting specific malignancies with defined genetic lesions has proven to be remarkably effective. Recent efforts to characterize the spectrum of genetic lesions found in non-small cell lung carcinoma (NSCLC) have provided important insights into the molecular basis of this disease and have also revealed a wide array of tyrosine kinases that might be effectively targeted for rationally designed therapies. The findings of these studies, however, also provide a cautionary tale about the limitations of single-agent therapies, which fail to account for the genetic heterogeneity and pathway redundancy that characterize advanced NSCLC. Emergence of drug resistance mechanisms to specific TKIs, such as gefitinib and erlotinib, suggests that more sophisticated chemotherapeutic paradigms that target multiple pathways at the same time will be required to effectively treat this disease.

Multiplexed methylation profiles of tumor suppressor genes and clinical outcome in lung cancer

Background

Changes in DNA methylation of crucial cancer genes including tumor suppressors can occur early in carcinogenesis, being potentially important early indicators of cancer. The objective of this study was to examine a multiplexed approach to assess the methylation of tumor suppressor genes as tumor stratification and clinical outcome prognostic biomarkers for lung cancer.

Methods

A multicandidate probe panel interrogated DNA for aberrant methylation status in 18 tumor suppressor genes in lung cancer using a methylation-specific multiplex ligation-dependent probe amplification assay (MS-MLPA). Lung cancer cell lines (n = 7), and primary lung tumors (n = 54) were examined using MS-MLPA.

Results

Genes frequently methylated in lung cancer cell lines including SCGB3A1, ID4, CCND2 were found among the most commonly methylated in the lung tumors analyzed. HLTF, BNIP3, H2AFX, CACNA1G, TGIF, ID4 and CACNA1A were identified as novel tumor suppressor candidates methylated in lung tumors. The most frequently methylated genes in lung tumors were SCGB3A1 and DLC1 (both 50.0%). Methylation rates for ID4, DCL1, BNIP3, H2AFX, CACNA1G and TIMP3 were significantly different between squamous and adenocarcinomas. Methylation of RUNX3, SCGB3A1, SFRP4, and DLC1 was significantly associated with the extent of the disease when comparing localized versus metastatic tumors. Moreover, methylation of HTLF, SFRP5 and TIMP3 were significantly associated with overall survival.

Conclusions

MS-MLPA can be used for classification of certain types of lung tumors and clinical outcome prediction. This latter is clinically relevant by offering an adjunct strategy for the clinical management of lung cancer patients.

Gender-related disparities in non-small cell lung cancer

Epidemiological studies clearly outline some disparities in cancer onset, progression as well as prognosis and therapeutic response between sexes. In particular, in lung cancer, the leading cause of cancer death, at least in Western countries, a gender disparity appears now to emerge, especially for non-small cell lung cancer (NSCLC). Such a disparity is apparently due to a variety of mechanisms, ranging from genetic and epigenetic differences to gender-specific lifestyle as well as to behavioral causes and, clearly, to sex hormones activity. Here we briefly recapitulate gender differences in terms of risk factors, histopathological features and pathogenetic mechanisms in NSCLC, and hypothesize that a gender-oriented pharmacology could beneficially impact on innovative therapeutic strategies.

Anticancer actions of PPARγ ligands: Current state and future perspectives in human lung cancer

Peroxisome proliferator-activated receptors (PPARs) are ligand-dependent nuclear transcription factors and members of the nuclear receptor superfamily. Of the three PPARs identified to date (PPARγ, PPARβ/δ, and PPARα), PPARγ has been studied the most, in part because of the availability of PPARγ agonists (also known as PPARγ ligands) and its significant effects on the management of several human diseases including type 2 diabetes, metabolic syndrome, cardiovascular disease and cancers. PPARγ is expressed in many tumors including lung cancer, and its function has been linked to the process of lung cancer development, progression and metastasis. Studies performed in gynogenic and xenograft models of lung cancer showed decreased tumor growth and metastasis in animals treated with PPARγ ligands. Furthermore, data are emerging from retrospective clinical studies that suggest a protective role for PPARγ ligands on the incidence of lung cancer. This review summarizes the research being conducted in this area and focuses on the mechanisms and potential therapeutic effects of PPARγ ligands as a novel anti-lung cancer treatment strategy.

Chronic obstructive pulmonary disease: towards pharmacogenetics

Chronic obstructive pulmonary disease (COPD) is a common problem worldwide, and it is recognized that the term encompasses overlapping sub-phenotypes of disease. The development of a sub-phenotype may be determined in part by an individual's genetics, which in turn may determine response to treatment. A growing understanding of the genetic factors that predispose to COPD and its sub-phenotypes and the pathophysiology of the condition is now leading to the suggestion of individualized therapy based on the patients' clinical phenotype and genotype. Pharmacogenetics is the study of variations in treatment response according to genotype and is perhaps the next direction for genetic research in COPD. Here, we consider how knowledge of the pathophysiology and genetic risk factors for COPD may inform future management strategies for affected individuals.