Comprehensive analysis of oncogenic mutations in lung squamous cell carcinoma with minor glandular component

The HDAC2-MTA3 interaction induces nonsmall cell lung cancer cell migration and invasion by targeting c-Myc and cyclin D1

Genome-wide association studies have identified numerous single-nucleotide polymorphisms (SNPs) associated with lung cancer; however, the functions of histone deacetylase 2 (HDAC2) rs13213007 and HDAC2 in nonsmall cell lung cancer (NSCLC) remain unclear. Here we identified HDAC2 rs13213007 as a risk SNP and showed that HDAC2 was upregulated in both peripheral blood mononuclear cells (PBMCs) and NSCLC tissues with the rs13213007 A/A genotype compared with those with the rs13213007 G/G or G/A genotype. Patient clinical data indicated strong associations between rs13213007 genotype and N classification. Immunohistochemical staining confirmed that higher expression of HDAC2 was associated with NSCLC progression. Furthermore, we generated 293T cells with the rs13213007 A/A genotype using CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 gene editing. Chromatin immunoprecipitation sequencing followed by motif analysis showed that HDAC2 can bind to c-Myc in rs13213007 A/A 293T cells. Cell Counting Kit-8, colony formation, wound-healing, and Transwell assays revealed that HDAC2 upregulates c-Myc and cyclin D1 expression and promotes NSCLC cell proliferation, migration, and invasion. Co-immunoprecipitation, quantitative reverse transcription-polymerase chain reaction, and western blot analysis assays showed that MTA3 interacts with HDAC2, decreases HDAC2 expression, and rescues the migration and invasion abilities of NSCLC cells. Taken together, these findings identify HDAC2 as a potential therapeutic biomarker in NSCLC.

Comprehensive analyses of a CD8+ T cell infiltration related gene signature with regard to the prediction of prognosis and immunotherapy response in lung squamous cell carcinoma

Lung squamous cell carcinoma (LUSC) is associated with a worse prognosis than other histological subtypes of non-small cell lung cancer. Due to the vital role of CD8⁺ T cells in anti-tumor immunity, the characterization of CD8⁺ T cell infiltration-related (CTLIR) gene signature in LUSC is worthy of in-depth exploration. In our study, tumor tissues of LUSC patients from Renmin Hospital of Wuhan University were stained by multiplex immunohistochemistry to evaluate the density of infiltrated CD8⁺ T cells and explore the correlation with immunotherapy response. We found that the proportion of LUSC patients who responded to immunotherapy was higher in the high density of CD8⁺ T cell infiltration group than in the low density of CD8⁺ T cell infiltration group. Subsequently, we collected bulk RNA-sequencing data from The Cancer Genome Atlas (TCGA) database. The abundance of infiltrating immune cells in LUSC patients was analyzed by using CIBERSORT algorithm, and weighted correlation network analysis was performed to identify the co-expressed gene modules related to CD8⁺ T cells. We then developed a prognostic gene signature based on CD8⁺ T cell co-expressed genes and calculated the CTLIR risk score, which stratified LUSC patients into high-risk and low-risk groups. With univariate and multivariate analyses, the gene signature was identified as an independent prognostic factor in LUSC patients. The overall survival of LUSC patients in the high-risk group was significantly shorter than that of the low-risk group in the TCGA cohort, which was validated in Gene Expression Omnibus datasets. We analyzed immune cell infiltration in the tumor microenviroment and found fewer CD8⁺ T cells and more regulatory T cell infiltration in the high-risk group, which is characterized as an immunosuppressive phenotype. Furthermore, the LUSC patients in the high-risk group were predicted to have a better response to immunotherapy than those in the low-risk group when treated with PD-1 and CTLA4 inhibitors. In conclusion, we performed a comprehensive molecular analysis of the CTLIR gene signature in LUSC and constructed a risk model for LUSC patients to predict prognosis and immunotherapy response.

Clinical benefit of pembrolizumab in treatment of first line non-small cell lung cancer: a systematic review and meta-analysis of clinical characteristics

OBJECTIVE

Pembrolizumab has become an integral first line therapeutic agent for non-small cell lung cancer (NSCLC), but its potential predictive role in clinical and molecular characteristics remains to be clarified. Accordingly, we performed a systematic review and meta-analysis to evaluate the clinical benefit of pembrolizumab in treatment of first line NSCLC and to select individuals with the greatest potential benefit from pembrolizumab therapy, in order to obtain a more accurate treatment of NSCLC in immunotherapy.

METHODS

Mainstream oncology datasets and conferences were searched for randomized clinical trials (RCTs) published before August 2022. RCTs involved individuals with first line NSCLC treated with pembrolizumab monotherapy or in combination with chemotherapy. Two authors independently selected the studies, extracted data, and assessed the risk of bias. The basic characteristics of the included studies were recorded, along with 95 percent confidence intervals (CI) and hazard ratios (HR) for all patients and subgroups. The primary endpoint was overall survival (OS), and secondary endpoints was progression-free survival (PFS). Pooled treatment data were estimated using the inverse variance-weighted method.

RESULTS

Five RCTs involving 2,877 individuals were included in the study. Pembrolizumab-based therapy significantly improved OS (HR 0.66; CI 95%, 0.55-0.79; p < 0.00001) and PFS (HR 0.60; CI 95%, 0.40-0.91; p = 0.02) compared with chemotherapy. OS was substantially enhanced in individuals aged < 65 years (HR 0.59; CI 95%, 0.42-0.82; p = 0.002), males (HR 0.74; CI 95%, 0.65-0.83; p < 0.00001), with a smoking history (HR 0.65; CI 95%, 0.52-0.82; p = 0.0003), with PD-L1 tumor proportion score (TPS) < 1% (HR 0.55; CI 95%, 0.41-0.73; p < 0.0001) and TPS ≥ 50% (HR 0.66; CI 95%, 0.56-0.76; p < 0.00001), but not in individuals aged ≥ 75 years (HR 0.82; CI 95%, 0.56-1.21; p = 0.32), females (HR 0.57; CI 95%, 0.31-1.06; p = 0.08), never smokers (HR 0.57; CI 95%, 0.18-1.80; p = 0.34), or with TPS 1-49% (HR 0.72; CI 95%, 0.52-1.01; p = 0.06). Pembrolizumab significantly prolonged OS in NSCLC patients, regardless of histology type (squamous or non-squamous NSCLC), performance status (PS) (0 or 1), and brain metastatic status (all p < 0.05). Subgroup analysis revealed that pembrolizumab combined with chemotherapy had more favorable HR values than pembrolizumab monotherapy in improving the OS of individuals with different clinical and molecular features.

CONCLUSION

Pembrolizumab-based therapy is a valuable option for first line treating advanced or metastatic NSCLC. Age, sex, smoking history and PD-L1 expression status can be used to predict the clinical benefit of pembrolizumab. Cautiousness was needed when using pembrolizumab in NSCLC patients aged ≥ 75 years, females, never smokers, or in patients with TPS 1-49%. Furthermore, pembrolizumab in combination with chemotherapy may be a more effective treatment regimen.

Squamous cell lung carcinoma with gastrointestinal metastasis: a case report and review of literature

Squamous cell lung carcinoma (LUSC) originates from squamous cells and has a high rate of metastasis and recurrence. The lack of effective genetic targets and specific therapies has resulted in a poor prognosis for patients with LUSC. Gastrointestinal metastasis of LUSC is a rare occurrence in clinical practice. Patients with gastrointestinal metastasis usually have worse overall survival and the process of diagnosis is more complicated than those with metastasis elsewhere. What's more, there are no helpful guidelines for treating patients with a clinically confirmed diagnosis of gastrointestinal metastasis, which means the treatment method is limited. Here, we review the clinical features, diagnosis, and treatment of LUSC patients with gastrointestinal metastasis and report a rare case of LUSC accompanied by gastrointestinal metastasis. The patient was admitted to the hospital with coughing and hemoptysis. A tumor was found in his lung, and lesions were initially controlled with standard treatment. The patient's tumor re-occurred again shortly for which treatment was lacking. Without effective treatment methods, the disease was difficult to control. Our learnings from the case demonstrate that LUSC metastasizes to secondary lymphoid organs of the gastrointestinal tract, usually with a poor prognosis.

Innate lymphoid cells type 3 in cancer

Cancer is a multifactorial chronic illness caused by a combination of genetic and environmental factors. A tumor is more than just a collection of cancer cells, it also contains infiltrating and resident host cells that are constantly interacting with it. Innate lymphoid cells (ILCs) have been recently found to be within the tumor and its microenvironment in close relationship with cancer cells. Although ILCs lack an antigen-specific receptor, they can respond to environmental stress signals, aiding in the fast orchestration of an early immune response. They are tissue resident cells mostly located in mucosa and first barrier organs that have been mainly studied in the defense against pathogens, lymphoid development, and tissue repair, however, current research has begun to elucidate their involvement in carcinogenesis. Nevertheless, among all ILCs, ILC3s have been found to be the most controversial in terms of tumor immunity. It has been found that they enhance anti-tumor immunity by detecting cancerous cells and helping lymphocytes infiltrate tumors. However, some recent studies have revealed that IL-23 stimulating ILC3s may promote tumor growth. In this review, we have incorporated the most recent studies on the involvement of ILC3s in cancer development to offer an overview of the role of ILC3s in cancer emphasis on their particular activity in several organs primarily in the mucosa, but also in breast, pancreas, liver, and skin, realizing that their role likely depends on the tissue microenvironment and the subtype of ILC3s.

Identification of adenoid subtype characterized with immune-escaped phenotype in lung squamous carcinoma based on transcriptomics

Non-small cell lung cancer (NSCLC) is a heterogeneous disease, and its demarcation contributes to various therapeutic outcomes. However, a small subset of tumors shows different molecular features that are in contradiction with pathological classification. Unsupervised clustering was performed to subtype NSCLC using the transcriptome data from the TCGA database. Next, immune microenvironment features of lung adenocarcinoma (LUAD), lung squamous carcinoma (LUSC), and lung adenoid squamous carcinoma (LASC) were characterized. In addition, diagnostic biomarkers to demarcate LASC among LUSC were screened using weighted gene co-expression network analysis (WGCNA) and validated by the in-house cohort. LASC was identified as a novel subtype with adenoid transcriptomic features in LUSC, which exhibited the most immuno-escaped phenotype among all NSCLC subtypes. In addition, FOLR1 was identified as a biomarker for LASC discrimination using the WGCNA analysis, and its diagnostic value was validated by the in-house cohort. Moreover, FOLR1 was related to immuno-escaped tumors in LUSC but not in LUAD. Overall, we proposed a novel typing strategy in NSCLC and identified FOLR1 as a biomarker for LASC discrimination.

Linc00996 is a favorable prognostic factor in LUAD: Results from bioinformatics analysis and experimental validation

Background: Linc00996 has been reported in a variety of malignant tumors, but its potential role and significance in lung adenocarcinoma (LUAD) are not fully understood. The authors investigated the expression and biological behavior of Linc00996 in LUAD and elucidated the function of its potential target genes.

Materials and methods: The data of Linc00996 expression in cancers were derived from GEPIA. GEO and TCGA datasets were used to identify the differential expression of Linc00996 in LUAD and analyze the respective correlation between different expression levels and LUAD stage and survival prognosis. We further elucidated the potential biological processes and pathways involved with Linc00996 in LAUD by GSEA. ssGSEA was applied to explore the relationship between Linc00996 and immune activity. Finally, the clinical impact of Linc00996 was assessed in 61 patients with LUAD, and the biological functions of Linc00996 were determined by a series of experiments in vitro, such as CCK8, colony formation, migration, and invasion assays.

Results: Compared with adjacent normal lung tissues, Linc00996 was significantly downregulated in LUAD, and its expression was negatively correlated with T stage, N stage, and pathological stage. An in vitro study suggested that enhanced Linc00996 expression could inhibit cell proliferation, clonal formation, migration, and invasion in LUAD cell lines. Via GSEA and ssGSEA, we observed that Linc00996 might be connected with immune infiltration in LUAD, and Linc00996 might inhibit tumorigenesis and metastasis by regulating antigen processing and presentation, JAK-STAT3, and cell adhesion molecular signaling pathways.

Conclusion: Linc00996 is a novel tumor suppressor in LUAD and may suppress the tumorigenesis and metastasis of LUAD via the tumor-related signaling pathway, such as antigen processing and presentation, JAK-STAT3, and cell adhesion molecular signaling pathways.

Decreased sphingomyelin (t34:1) is a candidate predictor for lung squamous cell carcinoma recurrence after radical surgery: a case-control study

Background

To reduce disease recurrence after radical surgery for lung squamous cell carcinomas (SQCCs), accurate prediction of recurrent high-risk patients is required for efficient patient selection for adjuvant chemotherapy. Because treatment modalities for recurrent lung SQCCs are scarce compared to lung adenocarcinomas (ADCs), accurately selecting lung SQCC patients for adjuvant chemotherapy after radical surgery is highly important. Predicting lung cancer recurrence with high objectivity is difficult with conventional histopathological prognostic factors; therefore, identification of a novel predictor is expected to be highly beneficial. Lipid metabolism alterations in cancers are known to contribute to cancer progression. Previously, we found that increased sphingomyelin (SM)(d35:1) in lung ADCs is a candidate for an objective recurrence predictor. However, no lipid predictors for lung SQCC recurrence have been identified to date. This study aims to identify candidate lipid predictors for lung SQCC recurrence after radical surgery.

Methods

Recurrent (n = 5) and non-recurrent (n = 6) cases of lung SQCC patients who underwent radical surgery were assigned to recurrent and non-recurrent groups, respectively. Extracted lipids from frozen tissue samples of primary lung SQCC were analyzed by liquid chromatography-tandem mass spectrometry. Candidate lipid predictors were screened by comparing the relative expression levels between the recurrent and non-recurrent groups. To compare lipidomic characteristics associated with recurrent SQCCs and ADCs, a meta-analysis combining SQCC (n = 11) and ADC (n = 20) cohorts was conducted.

Results

Among 1745 screened lipid species, five species were decreased (≤ 0.5 fold change; P < 0.05) and one was increased (≥ 2 fold change; P < 0.05) in the recurrent group. Among the six candidates, the top three final candidates (selected by AUC assessment) were all decreased SM(t34:1) species, showing strong performance in recurrence prediction that is equivalent to that of histopathological prognostic factors. Meta-analysis indicated that decreases in a limited number of SM species were observed in the SQCC cohort as a lipidomic characteristic associated with recurrence, in contrast, significant increases in a broad range of lipids (including SM species) were observed in the ADC cohort.

Conclusion

We identified decreased SM(t34:1) as a novel candidate predictor for lung SQCC recurrence. Lung SQCCs and ADCs have opposite lipidomic characteristics concerning for recurrence risk.

Trial registration

This retrospective study was registered at the UMIN Clinical Trial Registry (UMIN000039202) on January 21, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08948-5.

Identification of Novel Biomarkers Related to Lung Squamous Cell Carcinoma Using Integrated Bioinformatics Analysis

BACKGROUND

Lung squamous cell carcinoma (LUSC) is one of the most common types of lung carcinoma and has specific clinicopathologic characteristics. In this study, we screened novel molecular biomarkers relevant to the prognosis of LUSC to explore new diagnostic and treatment approaches for this disease.

METHODS

We downloaded GSE73402 from the Gene Expression Omnibus (GEO) database. GSE73402 contains 62 samples, which could be classified as four subtypes according to their pathology and stages. Via weighted gene coexpression network analysis (WGCNA), the main module was identified and was further analyzed using differentially expressed genes (DEGs) analysis. Then, by protein-protein interaction (PPI) network and Gene Expression Profiling Interactive Analysis (GEPIA), hub genes were screened for potential biomarkers of LUSC.

RESULTS

Via WGCNA, the yellow module containing 349 genes was identified, and it is strongly related to the subtype of CIS (carcinoma in situ). DEGs analysis detected 180 genes that expressed differentially between the subtype of CIS and subtype of early-stage carcinoma (Stage I and Stage II). A PPI network of DEGs was constructed, and the top 20 genes with the highest correlations were selected for GEPIA database to explore their effect on LUSC survival prognosis. Finally, ITGA5, TUBB3, SCNN1B, and SERPINE1 were screened as hub genes in LUSC.

CONCLUSIONS

ITGA5, TUBB3, SCNN1B, and SERPINE1 may have great diagnostic and prognostic significance for LUSC and have great potential to be new treatment targets for LUSC.

Outcomes in 36 Patients with Stage IIIA-N2 Squamous Cell Carcinoma of the Lung Treated with Nab-Paclitaxel Plus Carboplatin as Neoadjuvant Therapy: A Prospective Study from a Single Center

Background

Whether nab-paclitaxel plus carboplatin as neoadjuvant therapy can benefit patients with resectable squamous cell carcinoma of the lung remains unclear. This prospective study aimed to investigate outcomes in patients with stage IIIA-N2 squamous cell carcinoma of the lung treated with nab-paclitaxel plus carboplatin as neoadjuvant therapy.

Material/Methods

Patients with stage IIIA-N2 squamous cell carcinoma of the lung were treated with nab-paclitaxel (100 mg/m², days 1, 8, and 15) and carboplatin (5 mg/(mL·min), day 1) for two 21-day cycles. The patients were followed every 3 months for 2 years and every 6 months after that. The primary endpoint was the downstaging rate. Secondary endpoints included objective response rate (ORR), margin-free (R0) resection, pathologic complete response (pCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

Among the 36 enrolled patients, 33 completed neoadjuvant chemotherapy, and 23 underwent surgery. The preoperative ORR was 50.0% (18/36). R0 resection was achieved in 22 (95.7%) of 23 patients. Major pathologic response and pCR were achieved in 8 (34.8%) and 2 (8.7%) patients, respectively. The overall downstaging rate was 47.8% (11/23). The median follow-up was 39.8 (32.5–41.0) months. For patients who underwent surgery, the median PFS and OS were 31.4 (95%CI: 10.4-not reached (NR)) and 45.0 (95%CI: 22.6-NR) months, respectively. The most common adverse events were neutropenia, anemia, and leukopenia.

Conclusions

This study preliminarily indicated a favorable effect of nab-paclitaxel plus carboplatin as neoadjuvant therapy without significant adverse events for stage IIIA-N2 squamous cell carcinoma of the lung. Future randomized controlled trials are needed to verify these results.

The Immune Heterogeneity Between Pulmonary Adenocarcinoma and Squamous Cell Carcinoma: A Comprehensive Analysis Based on lncRNA Model

Adenocarcinoma (AD) and squamous cell carcinoma (SCC) are both classified as major forms of non-small cell lung cancer, but differences in clinical prognoses and molecular mechanisms are remarkable. Recent studies have supported the importance of understanding immune status in that it influences clinical outcomes of cancer, and immunotherapies based on the theory of “immune editing” have had notable clinical success. Our study aimed to identify specific long non-coding (lnc) RNAs that control key immune-related genes and to use them to construct risk models for AD and SCC. Risk scores were used to separate patients into high- and low-risk groups, and we validated the prognostic significance of both risk scores with our own cohorts. A Gene Set Enrichment Analysis suggested that the immune responses of patients in the AD high-risk group and the SCC low-risk group tended to be weakened. Evaluation of immune infiltration revealed that the degree of infiltration of dendritic cells is of particular importance in AD. In addition, prediction of responses to immune checkpoint inhibitor (ICI) treatments, based on the T Cell Immune Dysfunction and Exclusion and immunophenoscore models, indicated that deterioration of the immune microenvironment is due mainly to T cell exclusion in AD patients and T cell dysfunction in SCC patients and that high-risk patients with SCC might benefit from ICI treatment. The prediction of downstream targets via The Cancer Proteome Atlas and RNA-seq analyses of a transfected lung cancer cell line indicated that the lncRNA LINC00996 is a potential therapeutic target in AD.

Value of serum tumor markers for predicting EGFR mutations in non-small cell lung cancer patients

OBJECTIVES

We investigated whether serum tumor markers (STMs) represent a valuable noninvasive tool to predict epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) patients.

METHODS

A retrospective analysis was performed for 143 NSCLC patients at the Peking University International Hospital from December 2014 to December 2019. EGFR mutations in the tumor tissues were identified by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and next generation sequencing (NGS). The relationships between EGFR mutation and several clinicopathological features were analyzed.

RESULT

EGFR mutation were found more frequently in female (56.67%, P = 0.01), never-smokers (55.26%, P = 0.004), and those with lung adenocarcinoma (ADC) (52.17%, P < 0.001). The positive mutation rate for the EGFR gene were higher in the squamous cell carcinoma antigen (SCCA)group (≤1.5 ng/ml) and in the gastrin-releasing peptide precursor (preGRP) increased group (≥69.2 pg/ml), and this difference was statistically significant (P < 0.05). Univariate logistic regression analysis demonstrated that females (Odd ratio [OR]: 2.435, 95% confidence interval [CI]: 1.232, 4.813, P = 0.01) and never-smokers (OR = 0.370; CI = 0.186, 0.734; P = 0.004), lung adenocarcinoma patients (OR = 9.091; CI = 2.599, 21.800; P = 0.001), the SCC group (≤1.5 ng/ml) (OR = 0.331, CI = 0.120, 0.914; P = 0.033), and the preGRP group (≥69.2 pg/ml) (OR = 5.478, CI = 1.462, 20.528; P = 0.012) patients were risk factors for EGFR gene mutation. Multivariate logistic regression analysis demonstrated that lung ADC and proGRP elevation were independent risk factors for predicting EGFR gene positivity (P < 0.05).

CONCLUSION

STMs are associated with mutant EGFR status and could be integrated with other clinical factors to facilitate the classification of EGFR mutation status among NSCLC patients.

PP4C facilitates lung cancer proliferation and inhibits apoptosis via activating MAPK/ERK pathway

PURPOSE

Protein phosphatase 4 catalytic subunit (PP4C) has been shown to play crucial regulatory roles in biological process and is frequently upregulated in cancer such as breast and colorectal carcinoma. However, the function and potential molecular mechanism of PP4C in lung cancer remains unclear.

METHODS

Bioinformatic analysis was used to detect the expression level and prognosis of patients. Western blot, quantitative real-time PCR (qRT-PCR), CCK8, 5-Ethynyl-2'-deoxyuridine (Edu) proliferation assay and flow cytometric were used to explore the function in lung cancer cells.

RESULTS

In this study, we found that PP4C was upregulated in lung cancer tissues as compared with that in normal lung tissues. Furthermore, patients with high expression level of PP4C were correlated with a poor prognosis in lung cancer patients. In vitro, CCK8, Edu proliferation assays and flow cytometry analysis showed that PP4C could promote lung cancer cell growth and inhibit apoptosis. Mechanistic investigations revealed that PP4C may interact with PP4R1 and promote ERK activation. Additionally, PP4C depletion resulted in lower tumor growth in vivo.

CONCLUSIONS

Taken together, these data showed the oncogenic of PP4C in NSCLC tumorigenesis and provide a new insight of PP4C in the progression of NSCLC.

Predictive biomarkers for response to EGFR-directed monoclonal antibodies for advanced squamous cell lung cancer

Background

Upregulated expression and aberrant activation of the epidermal growth-factor receptor (EGFR) are found in lung cancer, making EGFR a relevant target for non-small-cell lung cancer (NSCLC). Treatment with anti-EGFR monoclonal antibodies (mAbs) is associated with modest improvement in overall survival in patients with squamous cell lung cancer (SqCLC) who have a significant unmet need for effective treatment options. While there is evidence that using EGFR gene copy number, EGFR mutation, and EGFR protein expression as biomarkers can help select patients who respond to treatment, it is important to consider biomarkers for response in patients treated with combination therapies that include EGFR mAbs.

Design

Randomized trials of EGFR-directed mAbs cetuximab and necitumumab in combination with chemotherapy, immunotherapy, or antiangiogenic therapy in patients with advanced NSCLC, including SqCLC, were searched in the literature. Results of associations of potential biomarkers and outcomes were summarized.

Results

Data from phase III clinical trials indicate that patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein (H-score of ≥200) and/or gene copy numbers of EGFR (e.g. ≥40% cells with ≥4 EGFR copies as detected by fluorescence in situ hybridization; gene amplification in ≥10% of analyzed cells) derive greater therapeutic benefits from EGFR-directed mAbs. Biomarker data are limited for EGFR mAbs used in combination with immunotherapy and are absent when used in combination with antiangiogenic agents.

Conclusions

Therapy with EGFR-directed mAbs in combination with chemotherapy is associated with greater clinical benefits in patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein and/or have increased EGFR gene copy number. These data support validating the role of these as biomarkers to identify those patients who derive the greatest clinical benefit from EGFR mAb therapy. However, data on biomarkers for EGFR-directed mAbs combined with immunotherapy or antiangiogenic agents remain limited.

Clinicopathological Characteristics And EGFR-TKIs Efficacies In Lung Squamous Cell Carcinoma Patients Harboring An EGFR Sensitizing Mutation

Objective

This study analyzed the relationship between the clinicopathological features and epidermal growth factor receptor (EGFR) mutation status of squamous cell lung cancer (SqCLC) patients. Mutation status was analyzed by comparing the amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and next-generation sequencing (NGS). We also assessed the efficacies of EGFR tyrosine kinase inhibitors (TKIs).

Methods

Retrospective analysis was performed for 292 SqCLC patients treated at the Guangxi Medical University Affiliated Tumor Hospital from December 2013 to December 2018. The EGFR mutations in tumor tissues were identified by ARMS-PCR and NGS. The affiliation between EGFR mutation and clinicopathological features was analyzed. Efficacies of EGFR-TKIs and survival were evaluated using the benchmarks of response evaluation criteria in solid tumors 1.1 (RECIST 1.1) and the Kaplan–Meier method, respectively.

Results

Among the 292 SqCLC patients, 24 (8.2%) were identified to have an EGFR-sensitizing mutation. Both ARMS-PCR and NGS were equally effective in detecting EGFR mutations. Females and non-smokers had higher EGFR mutation rates than males and smokers (22.1% vs. 5.1%, P = 0.007 and 16.7% vs. 4.5%, P = 0.001, respectively). EGFR mutation was unrelated to the degree of differentiation, clinical stage, specimen type and level of serum carcino-embryonic antigen (CEA) and squamous cell carcinoma antigen (SCC) (P > 0.05). In the 14 EGFR mutant cases treated with EGFR-TKIs, the objective response rate (ORR) and disease control rate (DCR) were 28.6% and 78.6%, respectively. Median progression-free survival (mPFS) and overall survival (mOS) were 4.9 and 10.75 months, respectively, with fine tolerance and mild side-effects.

Conclusion

EGFR-sensitizing mutations are rare in SqCLC patients with females and non-smokers having a higher risk of harboring them. There was no difference in the detection rates of EGFR for both the ARMS-PCR and NGS methods. EGFR-TKIs showed modest efficacies and low toxicity profiles in EGFR mutant cases.

Profiling the Mutational Landscape in Known Driver Genes and Novel Genes in African American Non-Small Cell Lung Cancer Patients

PURPOSE

Identifying novel driver genes and mutations in African American non-small cell lung cancer (NSCLC) cases can inform targeted therapy and improve outcomes for this traditionally underrepresented population.

EXPERIMENTAL DESIGN

Tumor DNA, RNA, and germline DNA were collected from African American NSCLC patients who participated in research conducted at the Karmanos Cancer Institute (KCI) in Detroit, Michigan. Known mutations were ascertained through the Sequenom LungCarta panel of 214 mutations in 26 genes, RET/ROS1 fusions, amplification of FGFR1, and expression of ALK. Paired tumor and normal DNA was whole-exome sequenced for a subset of cases without known driver mutations.

RESULTS

Of the 193 tumors tested, 77 known driver mutations were identified in 66 patients (34.2%). Sixty-seven of the 127 patients without a known driver mutation were sequenced. In 54 of these patients, 50 nonsynonymous mutations were predicted to have damaging effects among the 26 panel genes, 47 of which are not found in The Cancer Genome Atlas NSCLC white or African American samples. Analyzing the whole-exome sequence data using MutSig2CV identified a total of 88 genes significantly mutated at FDR q < 0.1. Only 5 of these genes were previously reported as oncogenic.

CONCLUSIONS

These findings suggest that broader mutation profiling including both known and novel driver genes in African Americans with NSCLC will identify additional mutations that may be useful in treatment decision-making.

IL23-Producing Human Lung Cancer Cells Promote Tumor Growth via Conversion of Innate Lymphoid Cell 1 (ILC1) into ILC3

PURPOSE

The plasticity of innate lymphoid cells (ILCs) has been reported in vitro and in the microenvironment of the intestine. However, whether ILC plasticity contributes to regulation of the tumor microenvironment remains unknown. In this study, we explored plasticity of ILCs in human lung cancer.

EXPERIMENTAL DESIGN

We analyzed immune subsets and cytokine expression in lung cancers freshly obtained from 80 patients and explored conversion of ILC1 into ILC3 in coculture with lung cancer cells. Prognostic effects of converted ILC3 and related pathway were evaluated by retrospective cohort composed of 875 patients with lung cancer.

RESULTS

Low percentages of ILC1, and high percentages of ILC3 were found in pulmonary squamous cell carcinomas (SqCC) but not adenocarcinomas (ADC). In non-small-cell lung cancers, the percentage of ILC3 was associated with IL23 expression in tumor cells but not immune cells. In cocultures, tumor cells of SqCCs converted ILC1 into ILC3 by producing IL23, thus promoting IL17-mediated tumor cell proliferation. Consistently, among IL17⁺ immune cells, the percentages of ILCs were higher in SqCCs than ADCs. Furthermore, the numbers of CD3^-RORγt⁺ ILC3, IL17 expression level, and IL23- or IL17RA-expressing tumor cells were associated with short survival of patients with SqCC but not ADC.

CONCLUSIONS

Conversion from ILC1 into ILC3 by IL23-producing SqCCs promotes IL17-mediated tumor progression, resulting in a poor prognosis.

Choice of the surgical approach for patients with stage I lung squamous cell carcinoma ≤3 cm

Background

We tried to explore the surgical procedures for stage I squamous cell carcinoma (SCC) with a size of ≤3 cm by using the Surveillance, Epidemiology, and End Results (SEER) database. Furthermore, we investigated the relationships between the chosen surgical option and the size of SCC.

Methods

In total, 1,147 patient data sets were collected from 2010 to 2011 using the SEER database. Afterwards, 849 patients with a pT1-2aN0M0 SCC with a size of ≤3 cm after a lobectomy or sublobectomy procedure were identified. Kaplan-Meier curves were conducted to compare the overall survival (OS) rates and the lung cancer-specific survival (LCSS) rates between the two surgical approaches. Cox proportional hazards regressions were performed to discover the independent risk factors for both the OS and LCSS rates. Lastly, subgroup analysis was stratified by the size of the SCC and then classified by the 8^th edition T category.

Results

The sublobectomy procedure did not demonstrate a difference for the OS rate. Additionally, it demonstrated a worse LCSS rate when compared with a lobectomy for stage I SCC. In the subgroup analysis, a lobectomy was shown to have a better survival outcome only when the SCC was >2 and ≤3 cm. Multivariable analysis showed that a size of >2 to ≤3 cm, and an age of >60 were independently associated with poorer OS while the sublobectomy procedure and pleural invasions (PI) were related with a poorer LCSS rate. In the stratification of data for the tumor size, the cox proportional analysis still confirmed the protective effects of the lobectomy in subgroups of SCCs with sizes between >2 to ≤3 cm as well as the T1c category.

Conclusions

The choice of the SCC surgery can be recommended based on the tumor size. A lobectomy procedure demonstrated a better LCSS against the sublobectomy in stage I SCC. SCC with sizes of >2 to ≤3 cm could become a pretty good indicator for lobectomy, while a sublobectomy may be an adequate substitute when the SCC size is ≤2 cm, especially for patients who cannot tolerate a lobectomy. T1c category can also suggest a lobectomy instead of sublobectomy for stage I SCC patients.

Comparative analysis of co-occurring mutations of specific tumor suppressor genes in lung adenocarcinoma between Asian and Caucasian populations

INTRODUCTION

Mutated tumor suppressor genes (TSG) such as TP53, STK11, and MGA are widely-reported. We hypothesized the presence of single mutation or co-occurring mutations in these specific genes may represent a significant therapeutic target for lung adenocarcinoma.

METHODS

We sequenced lung adenocarcinoma samples from 677 East-Asian patients, combined them with those from cBioPortal public database (including TCGA) and performed a comparative analysis between Asian and Caucasian populations.

RESULTS

East-Asian lung adenocarcinomas presented distinct driver-mutational distribution compared to that of Caucasians (79% vs 56%, p < 0.001). Similar results were observed in TSG mutations of TP53 (35% vs 46%, p = 0.150), STK11 (4% vs 17%, p = 0.006) and MGA (10% vs 4%, p = 0.166). Compared with none-mutational cases, the patients harboring TSG mutations are more likely to be male (p = 0.009), smokers (p < 0.001), and more advanced disease (p = 0.004). In addition, the TSG-mutated tumors had poorer differentiation (p < 0.001), and more likely to be solid or micropapillary-predominant adenocarcinomas (p < 0.001). Survival analysis showed that both overall survival (OS, p < 0.001) and post-recurrence survival (PRS, p < 0.001) became worse with the accumulation of TSG mutations. However, the prognostic variety was not found in Caucasian patients. Moreover, multivariate analysis proved the accumulation of TSG mutations independently predicts both unfavorable OS (HR = 0.435, 95% CI 0.245-0.774, p = 0.005) and PRS (HR = 0.491, 95% CI 0.269-0.894, p = 0.020) in East-Asian patients, adjusting all other survival-associated factors.

CONCLUSIONS

Co-occurring mutations of specific TSGs define unfavorable subgroups of lung adenocarcinoma, implying that the tumor promotion mechanisms contribute to the heterogeneity in tumor evolution. However, the Caucasian population did not show the same results, providing insights into the molecular basis underlying the striking racial disparities of this disease and evidence for different gene-panel designs for different population in the purpose of targeted therapy.

Identification a novel clinical biomarker in early diagnosis of human non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a malignant tumor with high morbidity and mortality. The clinical biomarkers currently used for the early diagnosis of lung cancer have poor sensitivity and specificity. Therefore, it is urgent to identify sensitive biomarkers for the early detection of NSCLC to improve the patient survival of patients. In our previously study, we identified glycoprotein alpha-1-antichymotrypsin (AACT) as an early biomarker of NSCLC. In this study, serum glycopeptides were enriched using the high-GlcNAc-specific binding lectin, AANL/AAL2, for further quantitative proteomics analysis using LC-MS/MS. A total of 55 differentially expressed proteins were identified by using demethylation labelling proteomics. Serum paraoxonase/arylesterase 1 (PON1) was selected for validation by western blotting and lectin-ELISA in samples from 120 enrolled patients. Our data showed that AANL-enriched PON1 has better diagnostic performance than total PON1 in early NSCLC, since it differed between early Stage I tumor samples and tumor-free samples (healthy and benign). Combining AANL-enriched PON1 with carcinoembryonic antigen (CEA) significantly improved the diagnostic specificity of CEA. Moreover, combined AANL-enriched PON1 and AANL-enriched AACT was significantly different between early NSCLC samples and tumor-free samples with an AUC of 0.940, 94.4% sensitivity, and 90.2% specificity. Our findings suggest that combined AANL-enriched PON1 and AANL-enriched AACT is a potential clinical biomarker for the early diagnosis of NSCLC.

Genetic alteration profiling of patients with resected squamous cell lung carcinomas

In this study, we analyzed the genetic profiles of squamous cell lung carcinoma (SqCLC) to identify potential therapeutic targets. Approximately 2,800 COSMIC mutations from 50 genes were determined by next-generation sequencing. Amplification/deletion of SOX2, CDKN2A, PTEN, FGFR1, EGFR, CCND1, HER2 and PDGFRA were detected by FISH and expression of VEGFR2, PD-L1 and PTEN were examined by IHC. One hundred and fifty-seven samples of SqCLC were collected. Somatic mutations was identified in 73.9% of cases, with TP53 (56.1%), CDKN2A (8.9%), PIK3CA (8.9%), KRAS (4.5%) and EGFR (3.2%). Gene copy number alterations were identified in 75.8% of cases, including SOX2 amplification (31.2%), CDKN2A deletion (21.7%), PTEN deletion (16.6%), FGFR1 amplification (15.9%), EGFR amplification (14.0%), CCND1 amplification (14.0%), HER2 amplification (9.6%) and PDGFRA amplification (7.6%). Positive expression of VEGFR2 and PD-L1 and loss of PTEN expression were observed in 80.5%, 47.2%, and 42.7% of cases, respectively. Multivariate analysis showed that positive expression of PD-L1 was an independent favorable prognostic factor for DFS (HR = 0.610; P = 0.044). In conclusion, nearly all (93.6%) SqCLC cases harbored at least one potential druggable target. The findings of this study could facilitate the identification of therapeutic target candidates for precision medicine of SqCLC.

Clinical and genetic features of lung squamous cell cancer in never-smokers

To evaluate the importance of specific driver mutations to the development and outcome of lung squamous cell cancer (SQCC) in never-smokers, we assessed the clinicopathological characteristics and outcomes of 597 patients who underwent complete resection of SQCCs. In total, 88 (14.7%) never-smokers and 509 (85.3%) ever-smokers were compared. The never-smokers included more females (42.05% vs. 1.57%, P < 0.001) and more often had a personal history of malignant disease (9.09% vs. 2.36%, P = 0.003). The tumors of never-smokers were more often poorly differentiated (70.45% vs. 53.24%, P = 0.010) and more often contained oncogenic mutations (21.05% vs 11.05%, P = 0.023), particularly EGFR mutations (13.16% vs 3.40%, P = 0.001). Never-smokers also tended to have poorer OS than smokers. Our results suggest lung SQCCs in never-smokers are a subtype distinct from SQCCs occurring in smokers.

Comprehensive investigation of clinicopathologic features, oncogenic driver mutations and immunohistochemical markers in peripheral lung squamous cell carcinoma

Background

Although the majority of lung squamous cell carcinomas (SQCC) arise in central airways, the prevalence of peripheral (p) SQCC is increasing. This study aimed to have a comprehensive investigation of clinicopathologic features, status of common driver mutations and immunophenotypes of p-SQCC compared to central (c) SQCC.

Methods

A total of 261 p-SQCC were compared to 444 c-SQCC for clinicopathologic characteristics. Comprehensive mutational analysis of EGFR, KRAS, HER2, BRAF, PIK3CA, DDR2, AKT1, ALK, ROS1, RET and FGFRs were performed. TTF1, CK7, Napsin A and PE10 protein expression were analyzed through immunohistochemistry (IHC). TTF1, CK7, CK8, SPA and TP63 gene expression levels were measured by quantitative real-time PCR.

Results

Compared to c-SQCC, p-SQCC were associated with female (14.2% vs. 4.5%, P<0.001), never-smokers (22.6% vs. 13.3%, P=0.001), older age at diagnosis (64.9 vs. 59.5 years, P<0.001) and lower pathologic stage (P<0.001). The frequency of EGFR mutations was significantly higher in p-SQCC than c-SQCC (6.2% vs. 2.2%, P=0.040). Positive protein expression of TTF1 (P=0.010) and CK7 (P=0.001) was significantly more prevalent in p-SQCC. p-SQCC had significantly higher gene expression of SPA (P=0.003), whereas c-SQCC showed higher gene expression of TP63 (P=0.028).

Conclusions

Lung p-SQCC had distinctive clinicopathologic characteristics and molecular features compared to c-SQCC, but showed some similarity with adenocarcinoma (ADC).

Unique distribution of programmed death ligand 1 (PD-L1) expression in East Asian non-small cell lung cancer

BACKGROUND

To determine the proportion and clinical features of programmed death ligand 1 (PD-L1) expression in East Asian non-small cell lung cancer (NSCLC).

METHODS

PD-L1 expression was assessed by immunohistochemistry (IHC) and tumor proportion score (TPS) with the use of PD-L1 IHC 22C3 antibody (Dako North America) in 108 surgically resected lung squamous cell carcinomas (SCC) and 221 lung adenocarcinomas (LUADs), and was correlated with clinical variables, histologic subtypes, and common driver mutations.

RESULTS

Positive PD-L1 expression was found in 37 lung SCC (37/108, 34.3%), including 15 cases with TPS ≥50% (15/108, 13.9%) and 22 cases with TPS <50% (22/108, 20.4%). In adenocarcinoma cohort, 9 cases were found PD-L1 expression positive (9/221, 4.1%), including 1 case with TPS ≥50% (1/221, 0.5%) and 8 cases with TPS <50% (8/221, 3.9%). Totally, high PD-L1 expression (TPS ≥50%) was significantly associated with male sex (P=0.026), current/ever smoking history (P=0.008) and SCC subtype (P<0.001). Positive PD-L1 expression (including TPS ≥50% and TPS <50%) in LUAD cohort was significantly associated with male sex (P=0.046), current/ever smoking history (P=0.002), mutation pan-negative status (P=0.038), solid-predominant subtype (P<0.001), large tumor size (P=0.027) and lymph node metastasis (P=0.019). No significant difference was found between PD-L1 high expression group (TPS ≥50%) and low/negative expression group in SCC cohort.

CONCLUSIONS

This study revealed the unique distribution of PD-L1 expression in East Asian NSCLCs, which is largely different from Western populations. Since the high response rate of pembrolizumab in the treatment of lung cancer patients with PD-L1 TPS ≥50%, this result indicates that prospective PD-L1 expression testing in specific East Asian patients could facilitate decision making for immunotherapy.

Second-line therapy of squamous non-small cell lung cancer: an evolving landscape

INTRODUCTION

The treatment of lung cancer has radically changed over the last few years. The discovery of druggable oncogenic alterations and the introduction of immunotherapy have provided lung cancer patients with the possibility of more efficient and less toxic therapeutic alternatives than chemotherapy. In the case of lung squamous cell carcinoma (LSCC), the treatment progress is slower than adenocarcinoma, for which several targeted agents have been already approved. The standard first-line therapy for LSCC, in most sites of the world, is platinum-based chemotherapy. After disease progression, these patients now have novel treatment options, including antiangiogenic agents and immune checkpoint blockade. Areas covered: We provide a summary of the recent novelties for the second-line therapy of LSCC, emphasizing on the results of the most important clinical trials that have led to regulatory approvals. Expert commentary: Immune checkpoint inhibitors have changed the therapeutic algorithm for LSCC patients. Other treatment options in the second-line setting include ramucirumab in combination with docetaxel and afatinib. However, we still lack biomarkers to predict which patients could respond better to each treatment. Despite the identification of several actionable molecular alterations, there are no approved targeted agents specific for advanced LSCC. Results from ongoing biomarker-driven studies are eagerly awaited to establish effective treatments for molecularly selected subgroups of patients.

Clinicopathological characteristics and survival of ALK, ROS1 and RET rearrangements in non-adenocarcinoma non-small cell lung cancer patients

BACKGROUND

ALK, ROS1 and RET rearrangements represent 3 most frequent fusion genes in non-small cell lung cancer (NSCLC). Rearrangements of these 3 genes exist predominantly in lung adenocarcinoma while rarely in non-adenocarcinoma. Our objective was to explore the frequency, clinicopathological characteristics and survival of ALK, ROS1 and RET rearrangements in non-adenocarcinoma NSCLC patients.

METHODS

ALK, ROS1 and RET rearrangements were screened by reverse transcriptase polymerase chain reaction (RT-PCR) in patients with completely resected non-adenocarcinoma NSCLC. All positive samples were confirmed with fluorescence in situ hybridization (FISH). Survival analysis was performed with Kaplan-Meier method and log-rank for comparison.

RESULTS

A total of 385 patients underwent complete resection, including squamous cell carcinoma (n = 245), adenosquamous carcinoma (n = 85) and large cell carcinoma (n = 55). Twelve of them were identified as harboring fusion genes, including ALK (n = 7), ROS1 (n = 3) and RET (n = 2) rearrangements. The fusion frequencies of adenosquamous, squamous cell and large cell carcinomas were 8.2%, 1.6% and 1.8% respectively. Their median age was 49.5 y and 3 of them had a smoking history. No survival difference existed between fusion gene positive and negative patients (36.7 vs.50.2 months, P = 0.21).

CONCLUSION

The frequencies of ALK, ROS1 and RET rearrangements are low in non-adenocarcinoma NSCLC patients. And their clinical characteristics are similar to those in lung adenocarcinoma. Fusions of the above 3 genes are not prognostic factor for non-adnocarcinoma NSCLC patients.

Comprehensive investigation of oncogenic driver mutations in Chinese non-small cell lung cancer patients

Purpose

To determine the frequency of driver mutations in Chinese non-small cell lung cancer (NSCLC) patients.

Methods

Comprehensive mutational analysis was performed in 1356 lung adenocarcinoma, 503 squamous cell carcinoma, 57 adenosquamous lung carcinoma, 19 large cell carcinoma and 8 sarcomatoid carcinoma. The effect of EGFR tyrosine kinase inhibitors (TKIs) on EGFR-mutated lung adenocarcinoma patients after disease recurrence was investigated.

Results

Mutations in EGFR kinase domain, HER2 kinase domain, KRAS, BRAF, ALK, ROS1 and RET were mutually exclusive. In lung adenocarcinoma cases “pan-negative” for the seven above-mentioned driver mutations, we also detected two oncogenic EGFR extracellular domain mutations (A289D and R324L), two HER2 extracellular and transmembrane domain mutations (S310Y and V659E), one ARAF S214C mutation and two CD74-NRG1 fusions. Six (1.2%) FGFR3 activating mutations were identified in lung squamous cell carcinoma (five S249C and one R248C). There were three (15.8%) EGFR mutations and four (21.1%) KRAS mutations in large cell carcinoma. Three (37.5%) KRAS mutations were detected in sarcomatoid carcinoma. In EGFR-mutated lung adenocarcinoma patients who experienced disease recurrence, treatment with EGFR TKIs was an independent predictor of better overall survival (HR = 0.299, 95% CI: 0.172–0.519, P < 0.001).

Conclusion

We determined the frequency of driver mutations in a large series of Chinese NSCLC patients. EGFR TKIs might improve the survival outcomes of EGFR-mutated lung adenocarcinoma patients who experienced disease recurrence.

MET exon 14 skipping defines a unique molecular class of non-small cell lung cancer

PURPOSE

Recurrent MET exon 14 splicing has been revealed in lung cancers and is a promising therapeutic target. Because we have limited knowledge about the natural history of MET mutant tumors, the current study was aiming to determine the clinical and pathological characteristics in non-small cell lung cancers (NSCLC).

RESULTS

Twenty-three patients (1.3%) were positive for MET exon 14 skipping. Patients with MET exon 14 skipping displayed unique characteristics: female, non-smokers, earlier pathology stage and older age. MET exon 14 skipping indicated an early event as other drivers in lung cancer, while MET copy number gain was more likely a late event in lung cancer. Overall survival (OS) of patients harboring MET exon 14 skipping was longer than patients with KRAS mutation. Almost four-fifths of the lung tumors with MET exon 14 skipping had EGFR and/or HER2 gene copy number gains. EGFR inhibitor showed moderate antitumor activity in treatment of a patient harboring MET exon 14 skipping.

PATIENTS AND METHODS

From October 2007 to June 2013, we screened 1770 patients with NSCLC and correlated MET status with clinical pathologic characteristics and mutations in EGFR, KRAS, BRAF, HER2, and ALK. Quantitative Real-Time PCR was used to detect MET gene copy number gain. Immunohistochemistry (IHC) was also performed to screen MET exon 14 skipping. Clinicopathological characteristics and survival information were analyzed.

CONCLUSIONS

MET exon 14 skipping was detected in 1.3% (23/1770) of the Chinese patients with NSCLC. MET exon 14 skipping defined a new molecular subset of NSCLC with identifiable clinical characteristics. The therapeutic EGFR inhibitors might be an alternative treatment for patients with MET mutant NSCLC.

Differences in driver genes between smoking-related and non-smoking-related lung cancer in the Chinese population

Recently, non-smoking-related lung cancer was classified as an independent disease entity because it is different from tobacco-associated lung cancer. Non-smoking-related lung cancer occurs more often in women than men, and the predominant histological type is adenocarcinoma (ADC) rather than squamous cell carcinoma. Most of the driver gene alterations that have been identified in ADC in never-smokers include epidermal growth factor receptor mutations, KRAS mutations, echinoderm microtubule-associated protein like 4/anaplastic lymphoma kinase fusion, and ROS1 fusion, among others. Meanwhile, significant progress has been made in the treatment of ADC. However, in comparison with ADC, no such available molecular targets exist for smoking-associated lung cancer, for which treatment strategies are limited. Next-generation sequencing has been widely applied to the discovery of more genetic profiles of lung cancers. This review summarizes the differences between smoking-related and non-smoking-related lung cancer as follows: different somatic mutation burdens, C:G→A:T transversions, common and novel driver genes, and treatment strategies. Overall, smoking-related lung cancer is more complicated than non-smoking-related lung cancer. Furthermore, we review the prevalence of driver genes in smoking-associated and non-smoking-associated lung cancers in the Chinese population.

Lung cancer molecular epidemiology in China: recent trends

Lung cancer is both the most common diagnosed cancer and the leading cause of cancer related deaths in China. During the past three decades, the incidence and mortality of lung cancer in China are increasing rapidly. According to data from National Central Cancer Registry (NCCR) in 2010, the crude incidence of lung cancer in China was 46.08 per 100,000 population (61.86 per 100,000 men and 29.54 per 100,000 women), with an estimated over 600,000 new diagnosed lung cancer patients (416,333 males and 189,613 females). Meanwhile, the crude mortality of lung cancer in China was 37.00 per 100,000 population (50.04 per 100,000 men and 23.33 per 100,000 women). Consistent with the change in developed countries, adenocarcinoma has become the most predominant histological subtype of lung cancer in China. For the majority advanced non-small-cell lung cancer (NSCLC) patients, especially patients with adenocarcinoma, targeted therapy became increasing important in the treatment. Chinese researcher have done a lot work in terms of lung cancer molecular epidemiology, therefore, in this review, we further summarized the epidemiology of driver genes in NSCLC, hoping to help clinicians to better screen certain driver genes in China for treatment decisions.

FGFR1/3 tyrosine kinase fusions define a unique molecular subtype of non-small cell lung cancer

PURPOSE

The fibroblast growth factor receptor (FGFR)-3 fusion genes have been recently demonstrated in a subset of non-small cell lung cancer (NSCLC). To aid in identification and treatment of these patients, we examined the frequency, clinicopathologic characteristics, and treatment outcomes of patients who had NSCLC with or without FGFR fusions.

EXPERIMENTAL DESIGN

Fourteen known FGFR fusion variants, including FGFR1, FGFR2, and FGFR3, were detected by RT-PCR and verified by direct sequencing in 1,328 patients with NSCLC. All patients were also analyzed for mutations in EGFR, KRAS, HER2, BRAF, ALK, RET, and ROS1. Clinical characteristics, including age, sex, smoking status, stage, subtypes of lung adenocarcinoma, relapse-free survival, and overall survival, were collected.

RESULTS

Of 1,328 tumors screened, two (0.2%) were BAG4-FGFR1 fusion and 15 (1.1%) were FGFR3-TACC3 fusion. Six of 1,016 patients with lung adenocarcinoma were FGFR3-TACC3 fusions and 11 of 312 lung squamous cell carcinoma harbored BAG4-FGFR1 or FGFR3-TACC3 fusions. Compared with the FGFR fusion-negative group, patients with FGFR fusions were more likely to be smokers (94.1%, 16 of 17 patients, P < 0.001), significantly associated with larger tumor (>3 cm; 88.2%, 15 of 17 patients, P < 0.001) and with a tendency to be more poorly differentiated (53.9%, nine of 17 patients, P = 0.095).

CONCLUSIONS

FGFR fusions define a molecular subset of NSCLC with distinct clinical characteristics. FGFR is a druggable target and patients with FGFR fusions may benefit from FGFR-targeted therapy, which needs further clinical investigation.