Personalized Therapy of Non-small Cell Lung Cancer (NSCLC)

Epigenetic regulation in lung cancer

Lung cancer is indeed a major cause of cancer-related deaths worldwide. The development of tumors involves a complex interplay of genetic, epigenetic, and environmental factors. Epigenetic mechanisms, including DNA methylation (DNAm), histone modifications, and microRNA expression, play a crucial role in this process. Changes in DNAm patterns can lead to the silencing of important genes involved in cellular functions, contributing to the development and progression of lung cancer. MicroRNAs and exosomes have also emerged as reliable biomarkers for lung cancer. They can provide valuable information about early diagnosis and treatment assessment. In particular, abnormal hypermethylation of gene promoters and its effects on tumorigenesis, as well as its roles in the Wnt signaling pathway, have been extensively studied. Epigenetic drugs have shown promise in the treatment of lung cancer. These drugs target the aberrant epigenetic modifications that are involved in the development and progression of the disease. Several factors have been identified as drug targets in non-small cell lung cancer. Recently, combination therapy has been discussed as a successful strategy for overcoming drug resistance. Overall, understanding the role of epigenetic mechanisms and their targeting through drugs is an important area of research in lung cancer treatment.

Prediction of risk and clinical outcome of cuproptosis in lung squamous carcinoma

BACKGROUND

Lung squamous cell carcinoma (LUSC) is an important subtype of non-small cell lung cancer. Its special clinicopathological features and molecular background determine the limitations of its treatment. A recent study published on Science defined a newly regulatory cell death (RCD) form - cuproptosis. Which manifested as an excessive intracellular copper accumulation, mitochondrial respiration-dependent, protein acylation-mediated cell death. Different from apoptosis, pyroptosis, necroptosis, ferroptosis and other forms of regulatory cell death (RCD). The imbalance of copper homeostasis in vivo will trigger cytotoxicity and further affect the occurrence and progression of tumors. Our study is the first to predict the prognosis and immune landscape of cuproptosis-related genes (CRGs) in LUSC.

METHODS

The RNA-seq profiles and clinical data of LUSC patients were downloaded from TCGA and GEO databases and then combined into a novel cohort. R language packages are used to analyze and process the data, and CRGs related to the prognosis of LUSC were screened according to the differentially expressed genes (DEGs). After analyzed the tumor mutation burden (TMB), copy number variation (CNV) and CRGs interaction network. Based on CRGs and DEGs, cluster analysis was used to classify LUSC patients twice. The selected key genes were used to construct a CRGs prognostic model to further analyze the correlation between LUSC immune cell infiltration and immunity. Through the risk score and clinical factors, a more accurate nomogram was further constructed. Finally, the drug sensitivity of CRGs in LUSC was analyzed.

RESULTS

Patients with LUSC were divided into different cuproptosis subtypes and gene clusters, showing different levels of immune infiltration. The risk score showed that the high-risk group had higher tumor microenvironment score, lower tumor mutation load frequency and worse prognosis than the low-risk group. In addition, the high-risk group was more sensitive to vinorelbine, cisplatin, paclitaxel, doxorubicin, etoposide and other drugs.

CONCLUSIONS

Through bioinformatics analysis, we successfully constructed a prognostic risk assessment model based on CRGs, which can not only accurately predict the prognosis of LUSC patients, but also evaluate the patient 's immune infiltration status and sensitivity to chemotherapy drugs. This model shows satisfactory predictive results and provides a reference for subsequent tumor immunotherapy.

d-Borneol enhances cisplatin sensitivity via autophagy dependent EMT signaling and NCOA4-mediated ferritinophagy

BACKGROUND

d-Borneol has been widely used as a drug absorption enhancer, but there are few studies on the anti-resistance ability of d-borneol combined with cisplatin in cisplatin-resistant non-small cell lung cancer cells. Ferroptosis, autophagy and epithelial-mesenchymal transition (EMT) have been reported to be associated with drug resistance.

PURPOSE

To investigate the molecular mechanisms and sensitizing effects of d-borneol combined with cisplatin to against drug cisplatin resistance from the perspective of ferroptosis, autophagy and EMT resistance.

METHODS

H460/CDDP xenograft tumor model was established to verify the antitumor activity and safety in vivo. RNA sequencing was used to predict target molecules and signaling pathways. Reactive oxygen species (ROS) were used as marker of ferroptosis, and its level was determined by a dichlorodihydrofluorescein diacetate fluorescent probe and flow cytometry. Levels of glutathione (GSH), malondialdehyde (MDA), and antioxidants such as superoxide dismutase (SOD) and thioredoxin (Trx) involved in the balance of oxidative stress were measured by an assay kit or enzyme-linked immunosorbent assay. Western blotting and real-time polymerase chain reaction were used to assess the regulatory mechanism of EMT markers, autophagy, and ferroptosis signaling pathways.

RESULTS

d-Borneol in combination with cisplatin reduced tumor volume and weight, enhanced tumor-inhibiting effects, and alleviated cisplatin-induced damage to the liver and kidney in vivo. RNA-sequencing showed that differentially expressed genes were enriched in ferroptosis. d-Borneol in combination with cisplatin promoted ROS accumulation, increased the content of MDA levels, and decreased GSH, SOD, Trx, and heme oxygenase-1 expression to induce oxidative damage. d-Borneol combination with cisplatin induced ferroptosis by promoting nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy and regulating intracellular iron ion transport via upregulating PRNP and downregulating PCBP2. In addition, d-borneol combined with cisplatin promoted autophagy by upregulating expression of LC3II/ATG5/Beclin-1 and inhibited the EMT by increasing the expression of epithelial marker E-cadherin and decreasing mesenchymal markers (N-cadherin and vimentin) and transcription factors (Snail and ZEB1).

CONCLUSION

For the first time, our study implies that d-borneol enhanced cisplatin sensitivity by inducing ferroptosis, promoting autophagy and inhibiting EMT progression, thereby enhancing antitumor activity. It suggests that d-borneol could be developed as a novel chemosensitizers.

Overexpression of TRAF4 promotes lung cancer growth and EGFR-dependent phosphorylation of ERK5

Tumor necrosis factor receptor-associated factor 4 (TRAF4) is overexpressed in a variety of carcinomas of different origins, but its role in tumorigenesis remains incompletely understood. Previous studies suggest that TRAF4 promotes epidermal growth factor receptor (EGFR) activation in non-small cell lung cancer (NSCLC). However, the downstream signaling pathway of TRAF4-mediated EGFR activation, as well as its effects on tumor cells, have not been fully elucidated. Here we report that TRAF4 overexpression is associated with increased activity of extracellular signal-regulated kinase 5 (ERK5) in NSCLC tissues. Activation of ERK5 was dependent on TRAF4-mediated EGFR activation, since inhibition of either TRAF4 or EGFR dramatically abolished phosphorylation of ERK5. Mechanistically, EGFR recruited mitogen-activated protein kinase kinase kinase 3 (MEKK3), an upstream kinase of ERK5, in a TRAF4-dependent manner. Thus, our data suggest that an EGFR-TRAF4-MEKK3-ERK5 axis promotes the proliferation of tumor cells, and this may be a potential target for therapeutic intervention of NSCLC.

Computed tomography-based radiomics quantification predicts epidermal growth factor receptor mutation status and efficacy of first-line targeted therapy in lung adenocarcinoma

Background

Biomarkers that predict the efficacy of first-line tyrosine kinase inhibitors (TKIs) are pivotal in epidermal growth factor receptor (EGFR) mutant advanced lung adenocarcinoma. Imaging-based biomarkers have attracted much attention in anticancer therapy. This study aims to use the machine learning method to distinguish EGFR mutation status and further explores the predictive role of EGFR mutation-related radiomics features in response to first-line TKIs.

Methods

We retrospectively analyzed pretreatment CT images and clinical information from a cohort of lung adenocarcinomas. We entered the top-ranked features into a support vector machine (SVM) classifier to establish a radiomics signature that predicted EGFR mutation status. Furthermore, we identified the best response-related features based on EGFR mutant-related features in first-line TKI therapy patients. Then we test and validate the predictive effect of the best response-related features for progression-free survival (PFS).

Results

Six hundred ninety-two patients were enrolled in building radiomics signatures. The 13 top-ranked features were input into an SVM classifier to establish the radiomics signature of the training cohort (n = 514), and the predictive score of the radiomics signature was assessed on an independent validation group with 178 patients and obtained an area under the curve (AUC) of 74.13%, an F1 score of 68.29%, a specificity of 79.55%, an accuracy of 70.79%, and a sensitivity of 62.22%. More importantly, the skewness-Low (≤0.882) or 10th percentile-Low group (≤21.132) had a superior partial response (PR) rate than the skewness-High or 10th percentile-High group (p < 0.01). Higher skewness (hazard ratio (HR) = 1.722, p = 0.001) was also found to be significantly associated with worse PFS.

Conclusions

The radiomics signature can be used to predict EGFR mutation status. Skewness may contribute to the stratification of disease progression in lung cancer patients treated with first-line TKIs.

The prevalence and prognostic significance of estrogen receptor beta expression in non-small cell lung cancer

Background

Estrogen receptor beta (ERβ) is the predominant estrogen receptor (ER) expressed in non-small cell lung cancer (NSCLC); however, due to methodological disparities among prior studies, the prognostic value of ERβ expression in NSCLC remains unclear. Our objective was to apply improved detection and analysis techniques to assess the prognostic value of ERβ expression in NSCLC.

Methods

A tissue microarray (TMA) was used which contained resected and biopsy specimens from 299 patients diagnosed at a single center with stages I-IV NSCLC. Sections of this array were stained using high-sensitivity fluorescence immunohistochemistry, with the well-validated PPG5/10 monoclonal antibody. Digital images of the stained array slides were analyzed using software-based image analysis, which reported ERβ expression as a continuous variable in different subcellular domains.

Results

There were no differences in ERβ expression between male and female patients. High expression of ERβ was not a prognostic factor, but was significantly associated with stage IV disease in both tumor and stroma (P<0.001). In multivariable analysis, a high nuclear/cytoplasmic (N/C) ratio of ERβ expression was significantly associated with shorter overall survival, based on expression in the tumor [hazard ratio (HR): 1.65; 95% confidence interval (CI): 1.25-2.19; P<0.001] and in the stroma (HR: 1.57; 95% CI: 1.16-2.12; P=0.003).

Conclusions

These results suggest that subcellular localization of ERβ, but not absolute expression, is a prognostic factor in NSCLC.

Gemcitabine inhibits cisplatin resistance in cisplatin-resistant A549 cells by upregulating trx-interacting protein and inducing cell cycle arrest

Cisplatin is a main chemotherapeutic drug used to treat non-small-cell lung cancer patients. However, these patients commonly face cisplatin resistance. The roles and underlying mechanisms of gemcitabine, irinotecan, pemetrexed and docetaxel used as single agents or combined with cisplatin for overcoming cisplatin-resistant non-small-cell lung cancer were explored in this study. MTT assays showed that gemcitabine alone exhibited stronger cytotoxicity on cisplatin-resistant A549 cells than irinotecan, pemetrexed and docetaxel. Meanwhile, gemcitabine combined with cisplatin showed a synergistic inhibitory effect on cisplatin-resistant cells. RNA sequencing and Gene Ontology/Kyoto Encyclopedia of Genes and Genomes analysis showed that cell cycle signaling pathways and trx-interacting protein were factors in the efficacy of the cotreatment. Flow cytometry and Western blot results showed that when cisplatin-resistant A549 cells were cotreated with gemcitabine and cisplatin, G0/G1 phase arrest occurred, and trx-interacting protein was upregulated. Silencing trx-interacting protein attenuated the response of the resistant cells to the drug combination. A trx-interacting protein agonist together with cisplatin showed an additive cytotoxic effect on the resistant cells compared with cisplatin alone. The gemcitabine and cisplatin combination, compared to gemcitabine or PBS alone, markedly suppressed the growth of cisplatin-resistant A549 tumors in vivo, accompanied by an increase in trx-interacting protein and a decrease in Ki67 expression. Therefore, we concluded that gemcitabine and cisplatin, as an FDA-approved combination, is a viable therapy for cisplatin-resistant non-small-cell lung cancer ex vivo and in vivo.

Beyond PD-L1 Markers for Lung Cancer Immunotherapy

Immunotherapy using immune checkpoints inhibitors has become the standard treatment for first and second line therapy in patients with non-small cell lung cancer (NSCLC). However, proper predictive factors allowing precise qualification of NSCLC patients for immunotherapy have not been developed so far. Expression of PD-L1 on tumor cells and tumor mutation burden are used in qualification of patients to first line therapy with pembrolizumab and atezolizumab in combination with ipilimumab in prospective clinical trials. Nevertheless, not all patients with these predictive factors benefit from immunotherapy. Major methodological difficulties in testing of these factors and in the interpretation of test results still exist. Therefore, other predictive factors are sought. Intensive research on the recognition of tumor immunophenotype and gut microbiome in NSCLC patients are underway. The first correlations between the effectiveness of immunotherapy and the intensity of inflammatory response in the tumor, microbiome diversity, and the occurrence of certain bacterial species in gut have been described. The purpose of our manuscript is to draw attention to factors affecting the efficacy of immunotherapy with anti-PD-L1 antibodies in NSCLC patients. Additional markers, for example TMB (tumor mutations burden) or microbiome profile, are needed to more accurately determine which patients will benefit from immunotherapy treatment.

Are There New Biomarkers in Tissue and Liquid Biopsies for the Early Detection of Non-Small Cell Lung Cancer?

Lung cancer is one of the most lethal malignancies worldwide, mainly due to its late diagnoses. The detection of molecular markers on samples provided from routine bronchoscopy including several liquid-based cytology tests (e.g., bronchoaspirate, bronchoalveolar lavage) and/or on easily obtained specimens such as sputum could represent a new approach to improve the sensitivity in lung cancer diagnoses. Recently growing interest has been reported for "noninvasive" liquid biopsy as a valuable source for molecular profiling. Unfortunately, a biomarker and/or composition of biomarkers capable of detecting early-stage lung cancer has yet to be discovered even if in the last few years there has been, through the use of revolutionary new technologies, an explosion of lung cancer biomarkers. Assay sensitivity and specificity need to be improved particularly when new approaches and/or tools are used. We have focused on the most important markers detected in tissue, and on several cytological specimens and liquid biopsies overall.

Chronic chemotherapy with paclitaxel nanoparticles induced apoptosis in lung cancer in vitro and in vivo

Aim

Paclitaxel (PTX) is an effective antitumor drug. Previous research demonstrated that paclitaxel nanoparticles (PTX-NPs) exhibited the greatest antitumor effect at 15 hours after light onset (15 HALO), but the mechanism in chronic chemotherapy is still unknown. In our study, we investigated whether PTX-NPs regulated Period2 (Per2) during chronic chemotherapy to induce apoptosis in vivo and in vitro.

Methods

To improve the antitumor effect and reduce organ damage induced by PTX treatment, PTX-NPs were prepared using a film dispersion method. Then, A549 cells were treated with PTX-NPs at 0, 5, 10, 15, and 20 HALO. An annexin/PI V-FITC apoptosis kit was measured for apoptosis, and PI was analyzed for cell cycle. The relative mechanism was detected by RT-PCR and Western blotting. Tumor volume and weight were measured to evaluate the antitumor effect of the PTX-NPs, and H&E staining was performed to assess organ damage.

Results

Cell cycle analysis demonstrated that PTX-NPs blocked cell cycle in G2 phase and that the ratio of cell death was significantly increased in A549 cells, while the ratios of cells in G2 phase and of apoptotic cells were highest at 15 HALO. Evaluation of in vivo antitumor activity revealed that PTX-NPs inhibited tumor growth and decreased tumor weight at 15 HALO. RT-PCR and Western blotting demonstrated that PTX-NPs upregulated Per2 mRNA and protein expression, and the highest Per2 expression was observed at 15 HALO in vivo and in vitro. Meanwhile, Bax mRNA and protein expression was upregulated, while Bcl-2 mRNA and protein expression was downregulated after PTX-NPs treatment in vivo. Moreover, H&E staining revealed that PTX-NPs reduced liver damage at 15 HALO.

Conclusion

PTX-NPs exhibited the most effective antitumor activity and reduced liver damage at 15 HALO through upregulation of Per2 expression to induce apoptosis in vivo and in vitro.

Hypermethylation of CCND2 in Lung and Breast Cancer Is a Potential Biomarker and Drug Target

Lung and breast cancer are the leading causes of mortality in women worldwide. The discovery of molecular alterations that underlie these two cancers and corresponding drugs has contributed to precision medicine. We found that CCND2 is a common target in lung and breast cancer. Hypermethylation of the CCND2 gene was reported previously; however, no comprehensive study has investigated the clinical significance of CCND2 alterations and its applications and drug discovery. Genome-wide methylation and quantitative methylation-specific real-time polymerase chain reaction (PCR) showed CCND2 promoter hypermethylation in Taiwanese breast cancer patients. As compared with paired normal tissues and healthy individuals, CCND2 promoter hypermethylation was detected in 40.9% of breast tumors and 44.4% of plasma circulating cell-free DNA of patients. The western cohort of The Cancer Genome Atlas also demonstrated CCND2 promoter hypermethylation in female lung cancer, lung adenocarcinoma, and breast cancer patients and that CCND2 promoter hypermethylation is an independent poor prognostic factor. The cell model assay indicated that CCND2 expression inhibited cancer cell growth and migration ability. The demethylating agent antroquinonol D upregulated CCND2 expression, caused cell cycle arrest, and inhibited cancer cell growth and migration ability. In conclusion, hypermethylation of CCND2 is a potential diagnostic, prognostic marker and drug target, and it is induced by antroquinonol D.

Disruption of Chromosomal Architecture of cox2 Locus Sensitizes Lung Cancer Cells to Radiotherapy

Despite treatment of lung cancer with radiotherapy and chemotherapy, the survival rate of lung cancer patients remains poor. Previous studies demonstrated the importance of upregulation of inflammatory factors, such as cyclooxygenase 2 (cox2), in tumor tolerance. In the present study, we investigated the role of cox2 in radiosensitivity of lung cancer. Our results showed that the combination treatment of radiation with aspirin, an anti-inflammatory drug, induced a synergistic reduction of cell survival in A549 and H1299 lung cancer cells. In comparison with normal human lung fibroblasts (NHLFs), the cell viability was significantly decreased and the level of apoptosis was remarkably enhanced in A549 cells. Mechanistic studies revealed that the reduction of cox2 by aspirin in A549 and H1299 was caused by disruption of the chromosomal architecture of the cox2 locus. Moreover, the disruption of chromatin looping was mediated by the inhibition of nuclear translocation of p65 and decreased enrichment of p65 at cox2-regulatory elements. Importantly, disorganization of the chromosomal architecture of cox2 triggered A549 cells sensitive to γ-radiation by the induction of apoptosis. In conclusion, we present evidence of an effective therapeutic treatment targeting the epigenetic regulation of lung cancer and a potential strategy to overcome radiation resistance in cancer cells.

Lung Cancer Therapy Targeting Histone Methylation: Opportunities and Challenges

Lung cancer is one of the most common malignancies. In spite of the progress made in past decades, further studies to improve current therapy for lung cancer are required. Dynamically controlled by methyltransferases and demethylases, methylation of lysine and arginine residues on histone proteins regulates chromatin organization and thereby gene transcription. Aberrant alterations of histone methylation have been demonstrated to be associated with the progress of multiple cancers including lung cancer. Inhibitors of methyltransferases and demethylases have exhibited anti-tumor activities in lung cancer, and multiple lead candidates are under clinical trials. Here, we summarize how histone methylation functions in lung cancer, highlighting most recent progresses in small molecular inhibitors for lung cancer treatment.

Imaging on Lung Cancer and Treatment with Targeted Therapy

The identification of genetic mutations known as oncogenic driver mutations that lead to the growth and survival of cancer cells has been an important advance in the field of oncology. Treatment in advanced non-small-cell lung cancer (NSCLC) has transitioned from a more general approach to a more personalized approach based on genetic mutations of the cancer itself. Common mutations detected in patients with advanced NSCLC include mutations of epidermal growth factor receptor and anaplastic lymphoma kinase (ALK). Targeted therapies are aimed at the products of these gene mutations and include erlotinib (used in epidermal growth factor receptor mutant NSCLC) and crizotinib (used in anaplastic lymphoma kinase positive NSCLC). In this review, we discuss common genetic mutations in advanced NSCLC, the role of targeted therapies, and imaging findings that can be associated with various genetic mutations.

Detection of sputum cofilin-1 as indicator of malignancy

Cofilin-1 (CFL1), a small protein of 18 kDa, has been studied as a biomarker due to its involvement in tumor cell migration and invasion. Our aim was to evaluate CFL1 as an indicator of malignancy and aggressiveness in sputum samples. CFL1 was analyzed by ELISA immunoassay in the sputum of 73 lung cancer patients, 13 cancer-free patients, and 6 healthy volunteers. Statistical analyses included ANOVA, ROC curves, Spearman correlation, and logistic regression. Sputum CFL1 levels were increased in cancer patients compared to cancer-free patients and volunteers (P<0.05). High expression of sputum CFL1 was correlated to T4 stage (P=0.01) and N stage (P=0.03), tobacco history (P=0.01), and squamous cell carcinoma histologic type (P=0.04). The accuracy of sputum CFL1 in discriminating cancer patients from cancer-free patients and healthy volunteers were 0.78 and 0.69, respectively. CFL1 at a cut-off value of 415.25 pg/mL showed sensitivity/specificity of 0.80/0.70 in differentiating between healthy volunteers and cancer patients. Sputum CFL1 was also able to identify cancer-free patients from patients with lung cancer. The AUC was 0.70 and, at a cut-off point ≥662.63 pg/mL, we obtained 60% sensitivity and 54% specificity. Logistic regression analysis controlled for tobacco history, histologic types, and N stage showed that cancer cell-associated CFL1 was an independent predictor of death. Smoker patients with squamous cell carcinoma, lymph node metastasis and sputum CFL1>1.475 pg/mL showed augmented chance of death, suggesting lung cancer aggressiveness. CFL1 presented diagnostic value in detecting lung cancer and was associated to tumor aggressiveness.

Targeted Therapy and Imaging Findings

Non-small cell lung cancer (NSCLC) is usually diagnosed when it is not amenable to curative surgery or radiation. Many of these patients are candidates for systemic therapy. Median survival is only approximately 10 months, and, accordingly, treatment in advanced NSCLC is evolving toward a more personalized approach with the identification of genetic abnormalities based on biomarkers. For example, gene mutations in EGFR (epidermal growth factor receptor) and ALK (anaplastic lymphoma kinase) lead to a cascade of pathways resulting in uncontrolled growth, proliferation, and survival of tumor cells. Targeted therapies are aimed at the products of these mutated genes and include agents such as erlotinib and gefitinib (in EGFR-mutant NSCLC) or crizotinib (in ALK-positive NSCLC). Antiangiogenesis agents such as bevacizumab are another category of targeted therapy that inhibits vascular endothelial growth factors. The imaging characteristics of advanced NSCLC with genetic abnormalities, the evolution of targeted therapies and their imaging manifestations will be discussed.

Targeted Therapy and Immunotherapy in the Treatment of Non-Small Cell Lung Cancer

The treatment strategy in advanced non-small cell lung cancer (NSCLC) has evolved from empirical chemotherapy to a personalized approach based on histology and molecular markers of primary tumors. Targeted therapies are directed at the products of oncogenic driver mutations. Immunotherapy facilitates the recognition of cancer as foreign by the host immune system, stimulates the immune system, and alleviates the inhibition that allows the growth and spread of cancer cells. The authors describes the role of targeted therapy and immunotherapy in the treatment of NSCLC, patterns of disease present on imaging studies, and immune-related adverse events encountered with immunotherapy.

Novel approaches against epidermal growth factor receptor tyrosine kinase inhibitor resistance

BACKGROUND

The identification and characterization of molecular biomarkers has helped to revolutionize non-small-cell lung cancer (NSCLC) management, as it transitions from target-focused to patient-based treatment, centered on the evolving genomic profile of the individual. Determination of epidermal growth factor receptor (EGFR) mutation status represents a critical step in the diagnostic process. The recent emergence of acquired resistance to "third-generation" EGFR tyrosine kinase inhibitors (TKIs) via multiple mechanisms serves to illustrate the important influence of tumor heterogeneity on prognostic outcomes in patients with NSCLC.

DESIGN

This literature review examines the emergence of TKI resistance and the course of disease progression and, consequently, the clinical decision-making process in NSCLC.

RESULTS

Molecular markers of acquired resistance, of which T790M and HER2 or MET amplifications are the most common, help to guide ongoing treatment past the point of progression. Although tissue biopsy techniques remain the gold standard, the emergence of liquid biopsies and advances in analytical techniques may eventually allow "real-time" monitoring of tumor evolution and, in this way, help to optimize targeted treatment approaches.

CONCLUSIONS

The influence of inter- and intra-tumor heterogeneity on resistance mechanisms should be considered when treating patients using resistance-specific therapies. New tools are necessary to analyze changes in heterogeneity and clonal composition during drug treatment. The refinement and standardization of diagnostic procedures and increased accessibility to technology will ultimately help in personalizing the management of NSCLC.

Improved EGFR mutation detection using combined exosomal RNA and circulating tumor DNA in NSCLC patient plasma

Background

A major limitation of circulating tumor DNA (ctDNA) for somatic mutation detection has been the low level of ctDNA found in a subset of cancer patients. We investigated whether using a combined isolation of exosomal RNA (exoRNA) and cell-free DNA (cfDNA) could improve blood-based liquid biopsy for EGFR mutation detection in non-small-cell lung cancer (NSCLC) patients.

Patients and methods

Matched pretreatment tumor and plasma were collected from 84 patients enrolled in TIGER-X (NCT01526928), a phase 1/2 study of rociletinib in mutant EGFR NSCLC patients. The combined isolated exoRNA and cfDNA (exoNA) was analyzed blinded for mutations using a targeted next-generation sequencing panel (EXO1000) and compared with existing data from the same samples using analysis of ctDNA by BEAMing.

Results

For exoNA, the sensitivity was 98% for detection of activating EGFR mutations and 90% for EGFR T790M. The corresponding sensitivities for ctDNA by BEAMing were 82% for activating mutations and 84% for T790M. In a subgroup of patients with intrathoracic metastatic disease (M0/M1a; n = 21), the sensitivity increased from 26% to 74% for activating mutations (P = 0.003) and from 19% to 31% for T790M (P = 0.5) when using exoNA for detection.

Conclusions

Combining exoRNA and ctDNA increased the sensitivity for EGFR mutation detection in plasma, with the largest improvement seen in the subgroup of M0/M1a disease patients known to have low levels of ctDNA and poses challenges for mutation detection on ctDNA alone.

Clinical Trials

NCT01526928.

Uncommon mutations in epidermal growth factor receptor and response to first and second generation tyrosine kinase inhibitors: A case series and literature review

Epidermal growth factor receptor (EGFR) is the most common driver gene involved in non small cell lung cancer (NSCLC) growth, being found in approximately 10-15% of Caucasian and 40% of Asian patients. A wide variety of pathogenic mutations, deletions, insertions and duplications have been described in EGFR exons 18-21. The presence of the most common among them (e.g. exon 21 L851R and exon 19 deletions) is associated to response to first and second generation EGFR tyrosine kinase inhibitors (TKIs), which have demonstrated clear superiority over chemotherapy in terms of both progression free survival (PFS) and overall survival (OS) in all treatment lines. However, scarcity of data exists in literature about the response of rarer EGFR alterations to first and second generation TKIs, most works consisting in sporadic case reports and small case series. In this review we aim to discuss the available evidence about this topic, in order to derive suggestions for clinical practice. Furthermore, we report seven cases of patients with lung tumors harboring uncommon EGFR mutations, treated in our Institution with first or second generation TKIs.

Liquid biopsy for early detection of lung cancer

PURPOSE OF REVIEW

The possibility of complete recovery for a lung cancer patient depends on very early diagnosis, as it allows total surgical resection. Screening for this cancer in a high-risk population can be performed using a radiological approach, but this holds a certain number of limitations. Liquid biopsy could become an alternative and complementary screening approach to chest imaging for early diagnosis of lung cancer.

RECENT FINDINGS

Several circulating biomarkers indicative of lung cancer can be investigated in blood, such as circulating tumor cells, circulating free nucleic acids (RNA and DNA) and proteins. However, none of these biomarkers have yet been adopted in routine clinical practice and studies are ongoing to confirm or not the usefulness and practical interest in routine early diagnosis and screening for lung cancers.

SUMMARY

Several potential circulating biomarkers for the early detection of lung cancer exist. When coupled to thoracic imaging, these biomarkers must give diagnosis of a totally resectable lung cancer and potentially provide new recommendations for surveillance by imagery of high-risk populations without a detectable nodule. Optimization of the specificity and sensitivity of the detection methods as well as standardization of the techniques is essential before considering for daily practice a liquid biopsy as an early diagnostic tool, or possibly as a predictive test, of lung cancer.

Graphene Oxide Induced Perturbation to Plasma Membrane and Cytoskeletal Meshwork Sensitize Cancer Cells to Chemotherapeutic Agents

The outstanding physicochemical properties endow graphene materials (e.g., graphene oxide, GO) with beneficial potentials in diverse biomedical fields such as bioimaging, drug delivery, and biomolecular detection. GO recently emerged as a chemosensitizer; however, the detailed molecular basis underlying GO-conducted sensitization and corresponding biological effects are still elusive. Based on our recent findings that GO treatment at sublethal concentrations could impair the general cellular priming state, including disorders of plasma membrane and cytoskeleton construction, we aimed here to explore the mechanism of GO as a sensitizer to make cancer cells more susceptible to chemotherapeutic agents. We discovered that GO could not only compromise plasma membrane and cytoskeleton in J774A.1 macrophages and A549 lung cancer cells at sublethal concentrations without incurring significant cell death but also dampen a number of biological processes. Using the toxicogenomics approaches, we laid out the gene expression signature affected by GO and further defined those genes involved in membrane and cytoskeletal impairments responding to GO. The mechanistic investigation uncovered that the interactions of GO-integrin occurred on the plasma membrane and consequently activated the integrin-FAK-Rho-ROCK pathway and suppressed the expression of integrin, resulting in compromised cell membrane and cytoskeleton and a subsequent cellular priming state. By making use of this mechanism, the efficacy of chemotherapeutic agents (e.g., doxorubicin and cisplatin) could be enhanced by GO pretreatment in killing cancer cells. This study unveiled a feature of GO in cancer therapeutics: sensitizing cancer cells to chemotherapeutic agents by undermining the resistance capability of tumor cells against chemotherapeutic agents, at least partially, by compromising plasma membrane and cytoskeleton meshwork.

Prognostic value of angiopoietin-2 in non-small cell lung cancer patients: a meta-analysis

Background

Non-small cell lung cancer (NSCLC) is the most frequent cause of cancer deaths worldwide. The targeted therapy had made important progress in recent years, but few potential predictive biomarkers for prognosis of NSCLC patients were identified. Angiopoietin-2 (Ang-2), a cytokine upregulated in tumor endothelial cells and some tumor cells including NSCLC, is a partial agonist and antagonist of angiopoietin-1 (Ang-1). Ang-1 is another ligand for the tyrosine kinase receptor Tie2; it promotes recruitment of pericytes and smooth muscle cells, stabilizing vascular networks by binding to Tie2. Although many studies mainly considered that Ang-2 correlated with progression and prognosis of NSCLC significantly, there are much conflicting and controversial data. Therefore, we conducted a meta-analysis to assess the relationship between Ang-2 and prognosis, a clinical outcome of NSCLC.

Methods

The search was based on major databases from PubMed, Cochrane Library, EMBASE, and CNKI, and 20 eligible publications (range from 2002 to 2015) are included in our meta-analysis with 2011 NSCLC patients in total. These studies illuminated the correlation between the expression of Ang-2 and NSCLC, based on either prognostic factors or clinicopathological features. Pooled calculations were carried out on the odds ratio (OR) and the corresponding 95 % confidence interval (CI) to perform this meta-analysis, and all statistical analyses were carried out by STATA 12.0 and Review Manager 5.3.

Results

According to our results, the expression of Ang-2 in NSCLC tissues was significantly higher than that in normal lung tissues, indicating that Ang-2 over-expression may be a predictive marker (pooled OR = 5.09, corresponding 95 % confidence interval (95 % CI) 3.10–8.36, p = 0.000). In addition, our pooled data showed that Ang-2 expression was positively correlated with tumor stages (pooled OR = 3.58, 95 % CI 2.40–5.35, p = 0.000), differentiation (pooled OR = 0.65, 95 % CI 0.45–0.94, p = 0.02), lymphatic invasion (pooled OR = 3.15, 95 % CI 1.97–5.03, p = 0.000), and poor survival (pooled OR = 1.93, 95 % CI 1.47–2.52, p = 0.000) of NSCLC, but seems to have no significant impact on tumor size (pooled OR = 1.09, 95 % CI 0.59–2.00, p = 0.78).

Conclusions

These results demonstrate that Ang-2 expression significantly correlated with poor prognosis for patients with NSCLC.