Treatment of advanced squamous cell carcinoma of the lung: a review

Bulk and single-cell RNA sequencing reveal the contribution of laminin γ2 -CD44 to the immune resistance in lymphocyte-infiltrated squamous lung cancer subtype

The high heterogeneity of lung squamous cell carcinomas (LUSC) and the complex tumor microenvironment lead to non-response to immunotherapy in many patients. Therefore, characterizing the heterogeneity of the tumor microenvironment in patients with LUSC and further exploring the immune features and molecular mechanisms that lead to immune resistance will help improve the efficacy of immunotherapy in such patients. Herein, we retrospectively analyzed the RNA sequencing (RNA-seq) data of 513 LUSC samples with other multiomics and single-cell RNA-seq data and validated key features using multiplex immunohistochemistry. We divided these samples into six subtypes (CS1-CS6) based on the RNA-seq data and found that CS3 activates the immune response with a high level of lymphocyte infiltration and gathers a large number of patients with advanced-stage disease but increases the expression of exhausted markers cytotoxic T-lymphocyte associated protein 4, lymphocyte-activation gene 3, and programmed death-1. The prediction of the response to immunotherapy showed that CS3 is potentially resistant to immune checkpoint blockade therapy, and multi-omic data analysis revealed that CS3 specifically expresses immunosuppression-related proteins B cell lymphoma 2, GRB2-associated binding protein, and dual-specificity phosphatase 4 and has a high mutation ratio of the driver gene ATP binding cassette subfamily A member 13. Furthermore, single-cell RNA-seq verified lymphocyte infiltration in the CS3 subtype and revealed a positive relationship between the expression of LAMC2-CD44 and immune resistance. LAMC2 and CD44 are epithelial-mesenchymal transition-associated genes that modulate tumor proliferation, and multicolor immunofluorescence validated the negative relationship between the expression of LAMC2-CD44 and immune infiltration. Thus, we identified a lymphocyte-infiltrated subtype (CS3) in patients with LUSC that exhibited resistance to immune checkpoint blockade therapy, and the co-hyperexpression of LAMC2-CD44 contributed to immune resistance, which could potentially improve immunological efficacy by targeting this molecule pair in combination with immunotherapy.

Prognostic analysis of lung squamous cell carcinoma patients with second primary malignancies: a SEER database study

Background

As lung squamous cell carcinoma (LUSC) patients are at increased risk of developing a second primary cancer, this complicates the patient's condition and thus makes prognostic assessment more difficult, posing a significant prognostic challenge for clinicians. Our goal was to assess the prognosis of LUSC patients with a second primary tumor, and provide insights into appropriate therapy and monitoring strategies.

Methods

Data was obtained for LUSC patients from the Surveillance, Epidemiology, and End Results (SEER) database. The LUSC patients were divided into three groups (LS-SPM, OT-LUSC and LUSC-only). Univariate and stratified analyses were performed for the baseline and clinical characteristics of the participants. Multiple regression and Kaplan-Meier survival analyses were also performed, followed by a final life table analysis.

Results

In our sample of 101,626 patients, the HR for OS in the LS-SPM group was 0.40 in univariate analysis. Kaplan-Meier survival curves showed that LS-SPM patients had considerably longer lifespans compared to the other groups. The LS-SPM patients had median and mean survival times of 64 months and 89.11 months. Unadjusted and adjusted multiple regression analyses showed that LS-SPM patients had a superior survival compared to LUSC-only and OT-LUSC groups.

Conclusion

LS-SPM patients have a good prognosis with aggressive therapy and immune monitoring. The present study offers novel insights into the pathophysiological causes and treatments for LS-SPM.

Long-Lasting Complete Remission in a Patient With Metastatic Metaplastic Breast Cancer Treated With Immune Checkpoint Inhibitor and Chemotherapy: A Case Report and a Review of the Literature

Metaplastic breast cancer (MpBC) is a rare form of breast cancer known for suboptimal response to chemotherapy, high recurrence rate, poor prognosis, and limited treatment options. Recent studies have reported that MpBC has high expression of programmed death ligand 1 and tumor-infiltrating lymphocytes, indicating the potential effectiveness of immunotherapy (IO) in MpBC. In addition, several reports have demonstrated the activity of IO in MpBC. In this case report, we present a case of recurrent MpBC that achieved durable, rapid, complete remission with atezolizumab (anti-PD-L1) and nab-paclitaxel with a continued response even after discontinued therapy.

Licochalcone A induces cell cycle arrest and apoptosis via suppressing MAPK signaling pathway and the expression of FBXO5 in lung squamous cell cancer

Lung squamous cell carcinoma (LSCC) is a highly heterogeneous malignancy with high mortality and few therapeutic options. Licochalcone A (LCA, PubChem ID: 5318998) is a chalcone extracted from licorice and possesses anticancer and anti‑inflammatory activities. The present study aimed to elucidate the anticancer effect of LCA on LSCC and explore the conceivable molecular mechanism. MTT assay revealed that LCA significantly inhibited the proliferation of LSCC cells with less cytotoxicity towards human bronchial epithelial cells. 5‑ethynyl‑2'‑deoxyuridine (EdU) assay demonstrated that LCA could reduce the proliferation rate of LSCC cells. The flow cytometric assays indicated that LCA increased the cell number of the G1 phase and induced the apoptosis of LSCC cells. LCA downregulated the protein expression of cyclin D1, cyclin E, CDK2 and CDK4. Meanwhile, LCA increased the expression level of Bax, cleaved poly(ADP‑ribose)polymerase‑1 (PARP1) and caspase 3, as well as downregulated the level of Bcl‑2. Proteomics assay demonstrated that LCA exerted its antitumor effects via inhibiting mitogen‑activated protein kinase (MAPK) signaling pathways and the expression of F‑box protein 5 (FBXO5). Western blot analysis showed that LCA decreased the expression of p‑ERK1/2, p‑p38MAPK and FBXO5. In the xenograft tumors of LSCC, LCA significantly inhibited the volumes and weight of tumors in nude mice with little toxicity in vital organs. Therefore, the present study demonstrated that LCA effectively inhibited cell proliferation and induced apoptosis in vitro, and suppressed xenograft tumor growth in vivo. LCA may serve as a future therapeutic candidate of LSCC.

Immune-active tumor-adjacent tissues are associated with favorable prognosis in stage I lung squamous cell carcinoma

The immunogenomic features of tumor-adjacent lungs (TALs) in stage I lung squamous cell carcinoma (LUSC) are not clear. Multiomics analyses of tumor tissues and paired TALs from 59 stage I LUSC patients were performed. Compared to tumors, TALs exhibited a better-preserved immune contexture indicated by upregulation of immune pathways, increased immune infiltration, and higher expression of immune effector molecules. Notably, TALs had no mutations in PTEN and KEAP1, a lower incidence of human leukocyte antigen (HLA) loss and higher expression of HLA class I genes, major histocompatibility complex (MHC) I chaperones, and interferon (IFN)-γ-associated genes. Digital spatial profiling validated the generally higher immune infiltration in TALs and revealed a higher level of immune heterogeneity in LUSC tumors. Importantly, patients with higher immune infiltration in TALs had significantly longer survival, while high immune heterogeneity was associated with inferior patient survival. Our work can be considered in the selection of patients for adjuvant therapy, especially immunotherapy.

Whole-tumor histogram analysis of multi-parametric MRI for differentiating brain metastases histological subtypes in lung cancers: relationship with the Ki-67 proliferation index

This study aims to investigate the predictive value of preoperative whole-tumor histogram analysis of multi-parametric MRI for histological subtypes in patients with lung cancer brain metastases (BMs) and explore the correlation between histogram parameters and Ki-67 proliferation index. The preoperative MRI data of 95 lung cancer BM lesions obtained from 73 patients (42 men and 31 women) were retrospectively analyzed. Multi-parametric MRI histogram was used to distinguish small-cell lung cancer (SCLC) from non-small cell lung cancer (NSCLC), and adenocarcinoma (AC) from squamous cell carcinoma (SCC), respectively. The T1-weighted contrast-enhanced (T1C) and apparent diffusion coefficient (ADC) histogram parameters of the volumes of interest (VOIs) in all BMs lesions were extracted using FireVoxel software. The following histogram parameters were obtained: maximum, minimum, mean, standard deviation (SD), variance, coefficient of variation (CV), skewness, kurtosis, entropy, and 1st-99th percentiles. Then investigated their relationship with the Ki-67 proliferation index. The skewness-T1C, kurtosis-T1C, minimum-ADC, mean-ADC, CV-ADC and 1st - 90th ADC percentiles were significantly different between the SCLC and NSCLC groups (all p < 0.05). When the 10th-ADC percentile was 668, the sensitivity, specificity, and accuracy (90.80%, 76.70% and 86.32%, respectively) for distinguishing SCLC from NSCLC reached their maximum values, with an AUC of 0.895 (0.824 - 0.966). Mean-T1C, CV-T1C, skewness-T1C, 1st - 50th T1C percentiles, maximum-ADC, SD-ADC, variance-ADC and 75th - 99th ADC percentiles were significantly different between the AC and SCC groups (all p < 0.05). When the CV-T1C percentiles was 3.13, the sensitivity, specificity and accuracy (75.00%, 75.60% and 75.38%, respectively) for distinguishing AC and SCC reached their maximum values, with an AUC of 0.829 (0.728-0.929). The 5th-ADC and 10th-ADC percentiles were strongly correlated with the Ki-67 proliferation index in BMs. Multi-parametric MRI histogram parameters can be used to identify the histological subtypes of lung cancer BMs and predict the Ki-67 proliferation index.

[Licochalcone A induces cell cycle arrest in human lung squamous carcinoma cells via the PI3K/Akt signaling pathway]

OBJECTIVE

To investigate the effect of licochalcone A (LCA) on the proliferation and cell cycle of human lung squamous carcinoma cells and explore its possible molecular mechanism.

METHODS

MTT assay was used to detect the changes in proliferation of H226 cells after treatment with different concentrations of LCA for 48 h, and the IC₅₀ of LCA was calculated. Flow cytometry was used to analyze cell cycle changes in H226 cells treated with 10, 20, and 40 μmol/L LCA, and the expressions of cyclin D1, cyclin-dependent kinase CDK2 and CDK4, and p-PI3K, PI3K, p-Akt, and Akt in the treated cells were detected using Western blotting. The effect of intraperitoneal injection of LCA for 24 days on tumor volume and weight was assessed in a BALB/c-nu mouse model bearing lung squamous carcinoma xenografts.

RESULTS

MTT assay showed that LCA significantly decreased the viability of H226 cells with an IC₅₀ of 28.3 μmol/L at 48 h. Flow cytometry suggested that LCA treatment induced obvious cell cycle arrest at the G1 phase. LCA treatment also significantly decreased the expressions of cyclin D1, CDK2, and CDK4, and inhibited the phosphorylation of PI3K and Akt in H226 cells. In the tumor-bearing mice, LCA treatment for 24 days significantly reduced the tumor volume and weight.

CONCLUSION

LCA is capable of inhibiting the proliferation and inducing cell cycle arrest in lung squamous carcinoma cells possibility by regulating the PI3K/Akt singling pathway.

Clinical characteristics and gene mutation profiles of chronic obstructive pulmonary disease in non-small cell lung cancer

Purpose

The coexistence of chronic obstructive pulmonary disease (COPD) often leads to a worse prognosis in patients with non-small cell lung cancer (NSCLC). Meanwhile, approaches targeting specific genetic alterations have been shown to significantly improve the diagnosis and treatment outcomes of patients with NSCLC. Herein, we sought to evaluate the impact of COPD on the clinical manifestations and gene mutation profiles of NSCLC patients with both circulating tumor (ctDNA) and tumor DNA (tDNA).

Materials and methods

The influence of COPD on clinical features was observed in 285 NSCLC cohorts suffering from NSCLC alone, NSCLC coexisting with COPD, or NSCLC coexisting with prodromal changes in COPD (with emphysema, bullae, or chronic bronchitis). The gene mutation profiles of specific 168 NSCLC-related genes were further analyzed in the NSCLC sub-cohorts with formalin-fixed and paraffin-embedded tumor DNA (FFPE tDNA) samples and plasma circulating tumor DNA (PLA ctDNA) samples. Moreover, mutation concordance was assessed in tDNA and paired ctDNA of 110 NSCLC patients.

Results

Relative to patients with NSCLC alone, patients with NSCLC coexisting with COPD and prodromal changes presented with worse lung functions, more clinical symptoms, signs and comorbidities, and inconsistent gene mutation profiles. In addition, patients in the latter two groups exhibited a higher average frequency of gene mutation. Lastly, mutation concordance between tDNA and ctDNA samples was significantly reduced in NSCLC patients coexisting with COPD.

Conclusions

Collectively, our findings revealed that coexistence of COPD leads to worse clinical manifestations and altered gene mutation profiles in patients with NSCLC. Additionally, for NSCLC patients with COPD, the use of ctDNA instead of tDNA may not be the most efficient approach to identifying gene mutations.

Clinicopathological implications of lncRNAs, immunotherapy and DNA methylation in lung squamous cell carcinoma: a narrative review

Objective

To explore the clinicopathological impact of lncRNAs, immunotherapy, and DNA methylation in lung squamous cell carcinoma (LUSC), emphasizing their exact roles in carcinogenesis and modes of action.

Background

LUSC is the second most prevalent form, accounting for around 30% of non-small cell lung cancer (NSCLC). To date, molecular-targeted treatments have significantly improved overall survival in lung adenocarcinoma patients but have had little effect on LUSC therapy. As a result, there is an urgent need to discover new treatments for LUSC that are based on existing genomic methods.

Methods

In this review, we summarized and analyzed recent research on the biological activities and processes of lncRNA, immunotherapy, and DNA methylation in the formation of LUSC. The relevant studies were retrieved using a thorough search of Pubmed, Web of Science, Science Direct, Google Scholar, and the university's online library, among other sources.

Conclusions

LncRNAs are the primary components of the mammalian transcriptome and are emerging as master regulators of a number of cellular processes, including the cell cycle, differentiation, apoptosis, and growth, and are implicated in the pathogenesis of a variety of cancers, including LUSC. Understanding their role in LUSC in detail may help develop innovative treatment methods and tactics for LUSC. Meanwhile, immunotherapy has transformed the LUSC treatment and is now considered the new standard of care. To get a better knowledge of LUSC biology, it is critical to develop superior modeling systems. Preclinical models, particularly those that resemble human illness by preserving the tumor immune environment, are essential for studying cancer progression and evaluating novel treatment targets. DNA methylation, similarly, is a component of epigenetic alterations that regulate cellular function and contribute to cancer development. By methylating the promoter regions of tumor suppressor genes, abnormal DNA methylation silences their expression. DNA methylation indicators are critical in the early detection of lung cancer, predicting therapy efficacy, and tracking treatment resistance. As such, this review seeks to explore the clinicopathological impact of lncRNAs, immunotherapy, and DNA methylation in LUSC, emphasizing their exact roles in carcinogenesis and modes of action.

The importance of enhancer methylation for epigenetic regulation of tumorigenesis in squamous lung cancer

Lung squamous cell carcinoma (LUSC) is a subtype of non-small cell lung cancer (NSCLC). LUSC occurs at the bronchi, shows a squamous appearance, and often occurs in smokers. To determine the epigenetic regulatory mechanisms of tumorigenesis, we performed a genome-wide analysis of DNA methylation in tumor and adjacent normal tissues from LUSC patients. With the Infinium Methylation EPIC Array, > 850,000 CpG sites, including ~350,000 CpG sites for enhancer regions, were profiled, and the differentially methylated regions (DMRs) overlapping promoters (pDMRs) and enhancers (eDMRs) between tumor and normal tissues were identified. Dimension reduction based on DMR profiles revealed that eDMRs alone and not pDMRs alone can differentiate tumors from normal tissues with the equivalent performance of total DMRs. We observed a stronger negative correlation of LUSC-specific gene expression with methylation for enhancers than promoters. Target genes of eDMRs rather than pDMRs were found to be enriched for tumor-associated genes and pathways. Furthermore, DMR methylation associated with immune infiltration was more frequently observed among enhancers than promoters. Our results suggest that methylation of enhancer regions rather than promoters play more important roles in epigenetic regulation of tumorigenesis and immune infiltration in LUSC.

Molecular cytogenetic characterization of the urethane-induced murine lung cell line LA-4 as a model for human squamous cell lung cancer

The murine tumor cell line LA-4 (also known as LA4 or LA 4) has been extensively used in ~70 studies from 1975 to present. However, the genetic characteristics have not been comprehensively delineated, apart from a single solid-stain cytogenetic study, which reported an average of 116 chromosomes per cell. LA-4 was created via urethane induction in an A/He mouse and demonstrated characteristic features of lung adenoma cells. In the present study, multicolor banding-based molecular cytogenetics was combined with molecular karyotyping to characterize ploidy, copy number alterations and chromosomal breakpoints of LA-4. A hyper-tetraploid karyotype with 85-93 chromosomes per cell, three distinct (pseudo-) dicentric derivatives, two neocentrics, four unbalanced translocations, two chromosomes with terminal deletions and one chromosome with a balanced inversion were detected. The results were translated into the human genome and a comparison with the literature revealed that LA-4 is well-suited as a murine model for human squamous cell lung cancer.

Primary lung tumour invading the chest wall

Introduction

This case study describes a primary lung tumour invading the chest wall, that clinically was thought likely to be a lipoma, and was imaged first using ultrasound.

Case Report

A 67 year old male presented to his GP with a six month history of a lump increasing in size on the left upper chest wall. The ultrasound scan demonstrated a hypoechoic and hypervascular soft tissue mass, extending out of the chest into the subcutaneous tissue and starting to erode the overlying rib. The appearances were highly suspicious for a chest malignancy. Further imaging and an ultrasound guided biopsy confirmed the diagnosis of a squamous cell carcinoma.

Discussion

The majority of patients who present to their general practitioner with a soft tissue mass commonly have benign abnormalities such as a lipoma or epidermoid cyst. Tumours of the chest wall are varied and are divided into benign and malignant tumours, and those that arise from the rib cage. Primary lung tumours are uncommonly seen on ultrasound. Lung cancers account for around 20% of all cancer deaths and the chest wall is involved in around 5% of primary lung tumours.

Conclusion

This case highlights the need for prompt investigation of enlarging superficial masses. Ultrasound imaging offers excellent detail for superficial structures and in this case, due to the location of the mass, identified a primary lung tumour.

Role of NRF2 in Lung Cancer

The gene expression program induced by NRF2 transcription factor plays a critical role in cell defense responses against a broad variety of cellular stresses, most importantly oxidative stress. NRF2 stability is fine-tuned regulated by KEAP1, which drives its degradation in the absence of oxidative stress. In the context of cancer, NRF2 cytoprotective functions were initially linked to anti-oncogenic properties. However, in the last few decades, growing evidence indicates that NRF2 acts as a tumor driver, inducing metastasis and resistance to chemotherapy. Constitutive activation of NRF2 has been found to be frequent in several tumors, including some lung cancer sub-types and it has been associated to the maintenance of a malignant cell phenotype. This apparently contradictory effect of the NRF2/KEAP1 signaling pathway in cancer (cell protection against cancer versus pro-tumoral properties) has generated a great controversy about its functions in this disease. In this review, we will describe the molecular mechanism regulating this signaling pathway in physiological conditions and summarize the most important findings related to the role of NRF2/KEAP1 in lung cancer. The focus will be placed on NRF2 activation mechanisms, the implication of those in lung cancer progression and current therapeutic strategies directed at blocking NRF2 action.

How mathematical modeling could contribute to the quantification of metastatic tumor burden under therapy: insights in immunotherapeutic treatment of non-small cell lung cancer

BACKGROUND

Cancer is one of the leading death causes globally with about 8.2 million deaths per year and an increase in numbers in recent years. About 90% of cancer deaths do not occur due to primary tumors but due to metastases, of which most are not clinically identifiable because of their relatively small size at primary diagnosis and limited technical possibilities. However, therapeutic decisions are formed depending on the existence of metastases and their properties. Therefore non-identified metastases might have huge influence in the treatment outcome. The quantification of clinically visible and invisible metastases is important for the choice of an optimal treatment of the individual patient as it could clarify the burden of non-identifiable tumors as well as the future behavior of the cancerous disease.

RESULTS

The mathematical model presented in this study gives insights in how this could be achieved, taking into account different treatment possibilities and therefore being able to compare therapy schedules for individual patients with different clinical parameters. The framework was tested on three patients with non-small cell lung cancer, one of the deadliest types of cancer worldwide, and clinical history including platinum-based chemotherapy and PD-L1-targeted immunotherapy. Results yield promising insights into the framework to establish methods to quantify effects of different therapy methods and prognostic features for individual patients already at stage of primary diagnosis.

A Retrospective Study on Using a Novel Single Needle Cone Puncture Approach for the Iodine-125 Seed Brachytherapy in Treating Patients With Thoracic Malignancy

Background

Patients with progressive thoracic malignancy characterized by large irregular tumors with necrosis and life-threatening symptoms lack effective treatments. We set out to develop a single needle cone puncture method for the Iodine-125 seed (SNCP-¹²⁵I) brachytherapy, and aim to report the initial results.

Methods

294 patients with advanced thoracic malignancy were treated with local SNCP-¹²⁵I brachytherapy between March 2009 and July 2020, followed by thorough evaluation of clinical outcome, overall survival (OS), progression-free survival (PFS) and procedure-related complications after treatment.

Results

The overall response rate (ORR) among the treated patients was 81.0% (238/294). Life-threatening symptoms due to tumor oppression, hemoptysis and large irregular tumor with necrosis were successfully alleviated after the SNCP-¹²⁵I treatment with a remission rate at 91% to 94%. The median OS and PFS were 13.6 months and 5.8 months, respectively. Procedure-related side effects including pneumothorax (32/294), blood-stained sputum (8/294), subcutaneous emphysema (10/294), puncture site bleeding (16/294) and chest pain (6/294) were observed. Patients who were able to follow with chemotherapy or immunotherapy experienced extended OS and PFS, as compared with patients who opted to receive hospice care (16.5 months Vs. 11.2 months). Further pathological and immunological analysis showed that SNCP-¹²⁵I induced tumor lymphocytes infiltration and long-term tumor necrosis.

Conclusion

SNCP-¹²⁵I brachytherapy effectively eliminates life-threatening symptoms due to local tumor oppression, hemoptysis and large irregular and necrotic tumors in patients with unresectable chest malignancy and significantly induces local tumor regression. SNCP-¹²⁵I brachytherapy combines with chemotherapy significantly prolong OS and PFS compare with SNCP-¹²⁵I brachytherapy alone.

Development of alternative splicing signature in lung squamous cell carcinoma

Increasing evidence demonstrated that alternative splicing (AS) plays a vital role in tumorigenesis and clinical outcome of patient. However, systematical analysis of AS in lung squamous cell carcinoma (LUSC) is lacking and greatly necessary. Thus, this study was to systematically estimate the function of AS events served as prognostic indicators in LUSC. Among 31,345 mRNA AS events in 9633 genes, we detected 1996 AS in 1409 genes which have significant connection with overall survival (OS) of LUSC patients. Then, prognostic model based on seven types of AS events was established and we further constructed a combined prognostic model. The Kaplan–Meier curve results suggested that seven types of AS signatures and the combined prognostic model could exhibit robust performance in predicting prognosis. Patients in the high-risk group had significantly shorter OS than those in the low-risk group. The ROC showed all prognostic models had high accuracy and powerful predictive performance with different AUC ranging from 0.837 to 0.978. Moreover, the combined prognostic model had highest performance in risk stratification and predictive accuracy than single prognostic models and had higher accuracy than other mRNA model. Finally, a significant correlation network between survival-related AS genes and prognostic splicing factors (SFs) was established. In conclusion, our study provided several potential prognostic AS models and constructed splicing network between AS and SFs in LUSC, which could be used as potential indicators and treatment targets for LUSC patients.

New Therapeutic Opportunities for the Treatment of Squamous Cell Carcinomas: A Focus on Novel Driver Kinases

Squamous cell carcinomas of the lung, head and neck, esophagus, and cervix account for more than two million cases of cancer per year worldwide with very few targetable therapies available and minimal clinical improvement in the past three decades. Although these carcinomas are differentiated anatomically, their genetic landscape shares numerous common genetic alterations. Amplification of the third chromosome's distal portion (3q) is a distinguishing genetic alteration in most of these carcinomas and leads to copy-number gain and amplification of numerous oncogenic proteins. This area of the chromosome harbors known oncogenes involved in squamous cell fate decisions and differentiation, including TP63, SOX2, ECT2, and PIK3CA. Furthermore, novel targetable oncogenic kinases within this amplicon include PRKCI, PAK2, MAP3K13, and TNIK. TCGA analysis of these genes identified amplification in more than 20% of clinical squamous cell carcinoma samples, correlating with a significant decrease in overall patient survival. Alteration of these genes frequently co-occurs and is dependent on 3q-chromosome amplification. The dependency of cancer cells on these amplified kinases provides a route toward personalized medicine in squamous cell carcinoma patients through development of small-molecules targeting these kinases.

Oxidative Stress and the Intersection of Oncogenic Signaling and Metabolism in Squamous Cell Carcinomas

Squamous cell carcinomas (SCCs) arise from both stratified squamous and non-squamous epithelium of diverse anatomical sites and collectively represent one of the most frequent solid tumors, accounting for more than one million cancer deaths annually. Despite this prevalence, SCC patients have not fully benefited from recent advances in molecularly targeted therapy or immunotherapy. Rather, decades old platinum-based or radiation regimens retaining limited specificity to the unique characteristics of SCC remain first-line treatment options. Historically, a lack of a consolidated perspective on genetic aberrations driving oncogenic transformation and other such factors essential for SCC pathogenesis and intrinsic confounding cellular heterogeneity in SCC have contributed to a critical dearth in effective and specific therapies. However, emerging evidence characterizing the distinct genomic, epigenetic, and metabolic landscapes of SCC may be elucidating unifying features in a seemingly heterogeneous disease. In this review, by describing distinct metabolic alterations and genetic drivers of SCC revealed by recent studies, we aim to establish a conceptual framework for a previously unappreciated network of oncogenic signaling, redox perturbation, and metabolic reprogramming that may reveal targetable vulnerabilities at their intersection.

Novel gene signatures for stage classification of the squamous cell carcinoma of the lung

The squamous cell carcinoma of the lung (SCLC) is one of the most common types of lung cancer. As GLOBOCAN reported in 2018, lung cancer was the first cause of death and new cases by cancer worldwide. Typically, diagnosis is made in the later stages of the disease with few treatment options available. The goal of this work was to find some key components underlying each stage of the disease, to help in the classification of tumor samples, and to increase the available options for experimental assays and molecular targets that could be used in treatment development. We employed two approaches. The first was based in the classic method of differential gene expression analysis, network analysis, and a novel concept known as network gatekeepers. The second approach was using machine learning algorithms. From our combined approach, we identified two sets of genes that could function as a signature to identify each stage of the cancer pathology. We also arrived at a network of 55 nodes, which according to their biological functions, they can be regarded as drivers in this cancer. Although biological experiments are necessary for their validation, we proposed that all these genes could be used for cancer development treatments.

Squamous cell carcinoma mimics small cell carcinoma of the lung: a case report

Squamous cell carcinomas (SCC) accounts for roughly 20% of lung cancers in the USA. The 2015 World Health Organization classification of lung tumors further categorizes SCC as three subtypes: keratinizing, non-keratinizing and basaloid variant. The non-keratinizing subtype is a poorly differentiated tumor that can present histologically in different ways, and one of which is a rare variant that strongly resembles small cell carcinoma. As a result, histological diagnosis alone is not sufficient to properly diagnose lung carcinomas. Immunohistochemistry has been increasingly used over the past few years to differentiate between lung tumors. The combination of morphological and immunohistochemical staining should be the mainstay for diagnosis of all lung carcinomas as more targeted therapies become more available.

Development of an Immune-Related Risk Signature for Predicting Prognosis in Lung Squamous Cell Carcinoma

Lung squamous cell carcinoma (LSCC) is the most common subtype of non-small cell lung cancer. Immunotherapy has become an effective treatment in recent years, while patients showed different responses to the current treatment. It is vital to identify the potential immunogenomic signatures to predict patient' prognosis. The expression profiles of LSCC patients with the clinical information were downloaded from TCGA database. Differentially expressed immune-related genes (IRGs) were extracted using edgeR algorithm, and functional enrichment analysis showed that these IRGs were primarily enriched in inflammatory- and immune-related processes. "Cytokine-cytokine receptor interaction" and "PI3K-AKT signaling pathway" were the most enriched KEGG pathways. 27 differentially expressed IRGs were significantly correlated with the overall survival (OS) of patients using univariate Cox regression analysis. A prognostic risk signature that comprises seven IRGs (GCCR, FGF8, CLEC4M, PTH, SLC10A2, NPPC, and FGF4) was developed with effective predictive performance by multivariable Cox stepwise regression analysis. Most importantly, the signature could be an independent prognostic predictor after adjusting for clinicopathological parameters, and also validated in two independent LSCC cohorts (GSE4573 and GSE17710). Potential molecular mechanisms and tumor immune landscape of these IRGs were investigated through computational biology. Analysis of tumor infiltrating lymphocytes and immune checkpoint molecules revealed distinct immune landscape in high- and low-risk group. The study was the first time to construct IRG-based immune signature in the recognition of disease progression and prognosis of LSCC patients.

PDX models of human lung squamous cell carcinoma: consideration of factors in preclinical and co-clinical applications

Background

Treatment of human lung squamous cell carcinoma (LUSC) using current targeted therapies is limited because of their diverse somatic mutations without any specific dominant driver mutations. These mutational diversities preventing the use of common targeted therapies or the combination of available therapeutic modalities would require a preclinical animal model of this tumor to acquire improved clinical responses. Patient-derived xenograft (PDX) models have been recognized as a potentially useful preclinical model for personalized precision medicine. However, whether the use of LUSC PDX models would be appropriate enough for clinical application is still controversial.

Methods

In the process of developing PDX models from Korean patients with LUSC, the authors investigated the factors influencing the successful initial engraftment of tumors in NOD scid gamma mice and the retainability of the pathological and genomic characteristics of the parental patient tumors in PDX tumors.

Conclusions

The authors have developed 62 LUSC PDX models that retained the pathological and genomic features of parental patient tumors, which could be used in preclinical and co-clinical studies.

Trial registration Tumor samples were obtained from 139 patients with LUSC between November 2014 and January 2019. All the patients provided signed informed consents. This study was approved by the institutional review board (IRB) of Samsung Medical Center (2018-03-110)

An integrative investigation on significant mutations and their down-stream pathways in lung squamous cell carcinoma reveals CUL3/KEAP1/NRF2 relevant subtypes

Background

Molecular mechanism of lung squamous cell carcinoma (LUSC) remains poorly understood, hampering effective targeted therapies or precision diagnosis about LUSC. We devised an integrative framework to investigate on the molecular patterns of LUSC by systematically mining the genomic, transcriptional and clinical information.

Methods

We utilized the genomics and transcriptomics data for the LUSC cohorts in The Cancer Genome Atlas.. Both kinds of omics data for 33 types of cancers were downloaded from The NCI’s Genomic Data Commons (GDC) (https://gdc.cancer.gov/about-data/publications/pancanatlas). The genomics data were processed in mutation annotation format (maf), and the transcriptomics data were determined by RNA-seq method. Mutation significance was estimated by MutSigCV. Prognosis analysis was based on the cox proportional hazards regression (Coxph) model.

Results

Significant somatic mutated genes (SMGs) like NFE2L2, RASA1 and COL11A1 and their potential down-stream pathways were recognized. Furthermore, two LUSC-specific and prognosis-meaningful subtypes were identified. Interestingly, the good prognosis subtype was enriched with mutations in CUL3/KEAP1/NRF2 pathway and with markedly suppressed expressions of multiple down-stream pathways like epithelial mesenchymal transition. The subtypes were verified by the other two cohorts. Additionally, primarily regulated down-stream elements of different SMGs were also estimated. NFE2L2, KEAP1 and RASA1 mutations showed remarkable effects on the subtype-determinant gene expressions, especially for the inflammatory relevant genes.

Conclusions

This study supplies valuable references on potential down-stream processes of SMGs and an alternative way to classify LUSC.

Construction and Validation of a Protein Prognostic Model for Lung Squamous Cell Carcinoma

Lung squamous cell carcinoma (LUSCC), as the major type of lung cancer, has high morbidity and mortality rates. The prognostic markers for LUSCC are much fewer than lung adenocarcinoma. Besides, protein biomarkers have advantages of economy, accuracy and stability. The aim of this study was to construct a protein prognostic model for LUSCC. The protein expression data of LUSCC were downloaded from The Cancer Protein Atlas (TCPA) database. Clinical data of LUSCC patients were downloaded from The Cancer Genome Atlas (TCGA) database. A total of 237 proteins were identified from 325 cases of LUSCC patients based on the TCPA and TCGA database. According to Kaplan-Meier survival analysis, univariate and multivariate Cox analysis, a prognostic prediction model was established which was consisted of 6 proteins (CHK1_pS345, CHK2, IRS1, PAXILLIN, BRCA2 and BRAF_pS445). After calculating the risk values of each patient according to the coefficient of each protein in the risk model, the LUSCC patients were divided into high risk group and low risk group. The survival analysis demonstrated that there was significant difference between these two groups (p= 4.877e-05). The area under the curve (AUC) value of the receiver operating characteristic (ROC) curve was 0.699, which suggesting that the prognostic risk model could effectively predict the survival of LUSCC patients. Univariate and multivariate analysis indicated that this prognostic model could be used as independent prognosis factors for LUSCC patients. Proteins co-expression analysis showed that there were 21 proteins co-expressed with the proteins in the risk model. In conclusion, our study constructed a protein prognostic model, which could effectively predict the prognosis of LUSCC patients.

Integrated evaluation of clinical, pathological and radiological prognostic factors in squamous cell carcinoma of the lung

Objective

Little is known about prognostic factors for lung squamous cell carcinoma (SCC). We aimed to explore radiologic and clinical factors affecting prognosis and to compare the prognosis of both central and peripheral lung SCCs.

Materials and methods

Radiologic, clinical, and pathologic profiles of surgically confirmed SCCs from 382 patients were retrospectively reviewed. Tumor location, enhancement, necrosis, the presence of obstructive pneumonitis/atelectasis and underlying lung disease were evaluated on chest CT examination. Age, pulmonary function, tumor marker, and cancer stage were also assessed. Univariate and multivariate Cox regression analyses were performed to identify any correlation to overall survival (OS) and disease-free survival (DFS). Hazard rate estimation and competing risk analysis were done to evaluate recurrence pattern.

Results

The median follow-up period was 56.2 months. Tumors were located centrally in 230 patients (60.2%) and peripherally in 152 patients (39.8%). Age (p = 0.002, hazard ratio [HR] 1.03, 95% confidence interval [CI] = [1.01, 1.06]) and interstitial lung abnormalities (ILAs) (p<0.001, HR 5.41, 95% CI = [3.08, 9.52]) were associated with poor OS on multivariate analysis. ILAs also had a strong association to DFS (p<0.001, HR 4.25, 95% CI = [3.08, 9.52]). Central cancers had two peaks of local recurrence development at 15 and 60 months after surgery, and peripheral tumors showed rising curves for metastasis development at 60 months.

Conclusions

CT-determined ILAs are a strong biomarker predicting poor outcome. Prognosis may not vary according to tumor location, but the two groups exhibited different recurrence patterns.

Identification of lncRNAs associated with lung squamous cell carcinoma prognosis in the competitive endogenous RNA network

Background

Long noncoding RNAs (lncRNAs) play a role in the formation, development, and prognosis of various cancers. Our study aimed to identify prognostic-related lncRNAs in lung squamous cell carcinoma (LUSC), which may provide new perspectives for individualized treatment of patients.

Materials and Methods

The RNA sequencing (lncRNA, microRNA (miRNA), mRNA) data and clinical information related to LUSC were obtained from The Cancer Genome Atlas (TCGA) database. Differentially expressed RNA sequences were used to construct the competitive endogenous RNA (ceRNA) network. In present study, we mainly used two prognostic verification methods, Cox analysis and survival analysis, to identify the prognostic relevance of specific lncRNAs and construct prognostic model of lncRNA.

Results

Datasets on 551 samples of lncRNA and mRNA and 523 miRNA samples were retrieved from the TCGA database. Analysis of the normal and LUSC samples identified 170 DElncRNAs, 331 DEmiRNAs, and 417 DEmRNAs differentially expressed RNAs. The ceRNA network contained 27 lncRNAs, 43 miRNAs, and 11 mRNAs. Furthermore, we identified seven specific lncRNAs (ERVH48-1, HCG9, SEC62-AS1, AC022148.1, LINC00460, C5orf17, LINC00261) as potential prognostic factors after correlation analysis, and five of the seven lncRNAs (AC022148.1, HCG9, LINC00460, C5orf17, LINC00261) constructed a prognostic model of LUSC.

Conclusion

In present study, we identified seven lncRNAs in the ceRNA network that are associated with potential prognosis in LUSC patients, and constructed a prognostic model of LUSC which can be used to assess the prognosis risk of clinical patients. Further biological experiments are needed to elucidate the specific molecular mechanisms underlying them.

Chronic Obstructive Pulmonary Disease and Lung Cancer: Underlying Pathophysiology and New Therapeutic Modalities

Chronic obstructive pulmonary disease (COPD) and lung cancer are major lung diseases affecting millions worldwide. Both diseases have links to cigarette smoking and exert a considerable societal burden. People suffering from COPD are at higher risk of developing lung cancer than those without, and are more susceptible to poor outcomes after diagnosis and treatment. Lung cancer and COPD are closely associated, possibly sharing common traits such as an underlying genetic predisposition, epithelial and endothelial cell plasticity, dysfunctional inflammatory mechanisms including the deposition of excessive extracellular matrix, angiogenesis, susceptibility to DNA damage and cellular mutagenesis. In fact, COPD could be the driving factor for lung cancer, providing a conducive environment that propagates its evolution. In the early stages of smoking, body defences provide a combative immune/oxidative response and DNA repair mechanisms are likely to subdue these changes to a certain extent; however, in patients with COPD with lung cancer the consequences could be devastating, potentially contributing to slower postoperative recovery after lung resection and increased resistance to radiotherapy and chemotherapy. Vital to the development of new-targeted therapies is an in-depth understanding of various molecular mechanisms that are associated with both pathologies. In this comprehensive review, we provide a detailed overview of possible underlying factors that link COPD and lung cancer, and current therapeutic advances from both human and preclinical animal models that can effectively mitigate this unholy relationship.

Effectiveness of first-line treatments in metastatic squamous non-small-cell lung cancer

Background

Commonly used first-line (1L) chemotherapies for patients with advanced squamous-cell lung cancer (scc) include gemcitabine-platinum (gp), nab-paclitaxel-carboplatin (nabpc), and sb-paclitaxel-carboplatin (sbpc) regimens. However, no head-to-head trials have compared those treatments. In the present study, we compared the efficacy of 1L gp, nabpc, and sbpc in patients with scc and in patients with scc who subsequently received second-line (2L) immunotherapy.

Methods

Medical records of patients who initiated the 1L treatments of interest between June 2014 and October 2015 were reviewed by 132 participating physicians. Kaplan-Meier curves were used to evaluate overall survival (os), progression-free survival (pfs), and treatment discontinuation (td), and then Cox proportional hazards regression was used to compare the results between the cohorts.

Results

Medical records of 458 patients with scc receiving gp (n = 139), nabpc (n = 159), or sbpc (n = 160) as 1L therapy were reviewed. Median os was longer with nabpc (23.9 months) than with gp (16.9 months; adjusted hazard ratio vs. nabpc: 1.55; p < 0.05) and with sbpc (18.3 months; adjusted hazard ratio: 1.42; p = 0.10). No differences were observed in pfs (median pfs: 8.8, 8.0, and 7.6 months for gp, nabpc, and sbpc respectively; log-rank p = 0.76) or in td (median td: 5.5, 5.7, and 4.6 months respectively; p = 0.65). For patients who subsequently received 2L immunotherapy, no differences in os were observed (median os: 27.3, 25.0, and 23.0 months respectively; p = 0.59).

Conclusions

In a nationwide sample of scc patients, longer median os was associated with 1L nabpc than with gp and sbpc. Median os for all 1L agents considered was similar in the subgroup of patients who sequenced to a 2L immunotherapy.

Endogenous arginase 2 as a potential biomarker for PEGylated arginase 1 treatment in xenograft models of squamous cell lung carcinoma

Depletion of arginine induced by PEGylated arginase 1 (ARG1) (BCT-100) has shown anticancer effects in arginine auxotrophic cancers that lack argininosuccinate synthetase (ASS1) and ornithine transcarbamylase (OTC). High levels of endogenous arginase 2 (ARG2) have been previously reported in human lung cancers. Although a high-ARG2 level neither causes immunosuppression nor affects disease progression, it may theoretically affect the efficacy of PEGylated ARG1 treatment. ARG2 was shown to be highly expressed in H520 squamous cell lung carcinoma (lung SCC) xenografts but undetectable in SK-MES-1 and SW900 lung SCC xenografts. We propose that high-endogenous expression of ARG2 could impede the anti-tumor effect of PEGylated ARG1 in lung SCC. The in vivo effect of PEGylated ARG1 was investigated using three xenograft models of lung SCC. PEGylated ARG1 (60 mg/kg) suppressed tumor growth in SK-MES-1 and SW900 but not H520 xenografts. ASS1 was expressed in SK-MES-1 and SW900 xenografts while OTC expression remained low in all xenografts. A high-endogenous ARG2 level was detected only in H520 xenografts. Serum arginine level was decreased significantly by PEGylated ARG1 in all xenografts. Nonetheless intratumoral arginine level was decreased by PEGylated ARG1 in SK-MES-1 and SW900, not H520 xenografts. In SK-MES-1 xenografts, PEGylated ARG1 treatment induced G1 arrest, downregulation of Ki67 and Mcl-1 and activation of apoptosis. In SW900 xenografts, upregulation of Bim and activation of apoptosis were observed upon PEGylated ARG1 treatment. Silencing of ARG2 re-sensitized the H520 xenografts to PEGylated ARG1 treatment, partially mediated through arginine depletion via G1 arrest and apoptosis. PEGylated ARG1 treatment (BCT-100) was effective in lung SCC xenografts with low-endogenous levels of ASS1/OTC and ARG2. High-endogenous ARG2 expression may cause resistance to PEGylated ARG1 treatment in lung SCC xenografts. ARG2 may serve as a third predictive biomarker in PEGylated ARG1 treatment in lung SCC.

[Microwave Hyperthermia Combined with Gemcitabine Inhibits Proliferation and Induces Apoptosis of Human Lung Squamous Carcinoma Cells]

BACKGROUND

Lung cancer is one of the highest morbidity and mortality in the world and it is very important to find an effective anti-tumor method. Microwave hyperthermia, a new treatment technology, has been getting more and more attention. This study was designed to investigate the effects of microwave hyperthermia combined with gemcitabine on the proliferation and apoptosis of human lung squamous cell carcinoma (NCI-H1703 and NCI-H2170) in vitro.

METHODS

The proliferation of cells treated with microwave hyperthermia, the effect of gemcitabine on cell proliferation and the proliferation of cells treated with different methods of microwave hyperthermia and gemcitabine were detected by CCK-8 assay. Colony formation assay was used to measure the colony formation of human lung squamous cell carcinoma cells. Flow cytometry assay was used to detect the total apoptosis rates of the treated cells. Caspase-3, Caspase-8 activity assay was used to detect the activity of Caspase-3, Caspase-8 enzyme in each group of cells. CCK-8 assay was used to detect the effect of control group, AC-DEVD (Caspase-3 inhibitor) group, thermalization combined group, and thermal AC-DEVD combined group on cell proliferation. The levels of p53, Caspase-3, Cleaved-Caspase-3, PARP, Bax and BCL-2 protein expression were detected using Western blot assay.

RESULTS

Our results demonstrated that microwave hyperthermia inhibited the proliferation of lung squamous cell carcinoma. The IC₅₀ values of gemcitabine for the two cells were 8.89 μmol/L and 44.18 μmol/L, respectively. The first chemotherapy after microwave hyperthermia has synergistic effect on the two lung squamous cell carcinoma cells and can significantly inhibit the cell clone formation (P<0.001), promote cell apoptosis (P<0.001) and increase Caspase-3 enzyme activity (P<0.001). However, it has no effect on Caspase-8 enzyme activity (P>0.05). Furthermore, Western blot analysis showed that microwave hyperthermia combined with gemcitabine could up-regulate the p53, Caspase-3, Cleaved-Caspase-3, Cleaved-PARP and Bax protein expression.

CONCLUSIONS

Microwave hyperthermia combined with gemcitabine remarkably inhibit the proliferation and induce apoptosis of human lung squamous cell carcinoma in vitro. This effect may be associated with the activation of p53, cleavage of PARP protein, and induced the Caspase-3 dependent apoptosis.

Identification of beta-arrestin-1 as a diagnostic biomarker in lung cancer

Background

Distinguishing lung adenocarcinoma (ADC) from squamous cell carcinoma (SCC) has a tremendous therapeutic implication. Sometimes, the commonly used immunohistochemistry (IHC) markers fail to discriminate between them, urging for the identification of new diagnostic biomarkers.

Methods

We performed IHC on tissue microarrays from two cohorts of lung cancer patients to analyse the expression of beta-arrestin-1, beta-arrestin-2 and clinically used diagnostic markers in ADC and SCC samples. Logistic regression models were applied for tumour subtype prediction. Parallel reaction monitoring (PRM)-based mass spectrometry was used to quantify beta-arrestin-1 in plasma from cancer patients and healthy donors.

Results

Beta-arrestin-1 expression was significantly higher in ADC versus SCC samples. Beta-arrestin-1 displayed high sensitivity, specificity and negative predictive value. Its usefulness in an IHC panel was also shown. Plasma beta-arrestin-1 levels were considerably higher in lung cancer patients than in healthy donors and were higher in patients who later experienced a progressive disease than in patients showing complete/partial response following EGFR inhibitor therapy.

Conclusions

Our data identify beta-arrestin-1 as a diagnostic marker to differentiate ADC from SCC and indicate its potential as a plasma biomarker for non-invasive diagnosis of lung cancer. Its utility to predict response to EGFR inhibitors is yet to be confirmed.

Elevated expression of podoplanin and its clinicopathological, prognostic, and therapeutic values in squamous non-small cell lung cancer

Background

Squamous non-small cell lung cancer (SqNSCLC), as a leading cause of cancer-related deaths worldwide, has limited treatment options and poor prognosis. Thus, novel targeted therapies are desperately needed.

Materials and methods

SqNSCLC cases from derivation and validation cohorts were ana-lyzed for podoplanin (PDPN) expression, and its clinicopathological correlation and prognostic prediction. The Human Proteome Map database was used to compare the expression of different lung cancer targets in normal human tissues. Two human lung cancer cell lines, H226 (a SqNSCLC line) and A549 (a non-SqNSCLC line), were examined for PDPN expression. The in vitro cytotoxicity of an anti-PDPN therapy (NZ-1-immunotoxin [NZ-1-IT]) was tested against both lines. The in vivo therapeutic effect of NZ-1-IT was examined in subcutaneous non-small cell lung cancer (NSCLC) xenograft mouse models.

Results

In the derivation cohort, 40% (28/70) were PDPN positive. There was significantly increasing pleural invasion (46.4% vs 9.5%, p=0.001), lymphovascular invasion (25.0% vs 9.5%, p=0.08), and lymph node involvement (53.6% vs 33.3%, p=0.09) in PDPN-positive vs PDPN-negative patients, along with poorer progression-free survival in PDPN-positive patients (p=0.07). The validation cohort with 224 randomly matched cases from The Cancer Genome Atlas data set also displayed significantly shorter overall survival in the group with elevated PDPN mRNA (p=0.05). However, PDPN showed limited expression in normal tissues. PDPN was highly and specifically expressed on the surface of H226 cells instead of A549 cells. Subsequently, PDPN-positive H226 cells were around 800 times more sensitive to anti-PDPN NZ-1-IT therapy than PDPN-negative A549 cells in vitro. Furthermore, NZ-1-IT significantly delayed tumorigenesis only in the H226 subcutaneous mouse model (p<0.05).

Conclusion

Our results demonstrate a distinctively elevated expression of PDPN in SqNSCLC, which is significantly associated with worse clinicopathological features and poorer prognosis. With promising preclinical therapeutic results, anti-PDPN targeted therapy can thus be a robust potential strategy for future SqNSCLC treatment.

Mutation profiles in early-stage lung squamous cell carcinoma with clinical follow-up and correlation with markers of immune function

Background

Lung squamous cell carcinoma (LUSC) accounts for 20–30% of non-small cell lung cancers (NSCLCs). There are limited treatment strategies for LUSC in part due to our inadequate understanding of the molecular underpinnings of the disease. We performed whole-exome sequencing (WES) and comprehensive immune profiling of a unique set of clinically annotated early-stage LUSCs to increase our understanding of the pathobiology of this malignancy.

Methods

Matched pairs of surgically resected stage I-III LUSCs and normal lung tissues (n = 108) were analyzed by WES. Immunohistochemistry and image analysis-based profiling of 10 immune markers were done on a subset of LUSCs (n = 91). Associations among mutations, immune markers and clinicopathological variables were statistically examined using analysis of variance and Fisher’s exact test. Cox proportional hazards regression models were used for statistical analysis of clinical outcome.

Results

This early-stage LUSC cohort displayed an average of 209 exonic mutations per tumor. Fourteen genes exhibited significant enrichment for somatic mutation: TP53, MLL2, PIK3CA, NFE2L2, CDH8, KEAP1, PTEN, ADCY8, PTPRT, CALCR, GRM8, FBXW7, RB1 and CDKN2A. Among mutated genes associated with poor recurrence-free survival, MLL2 mutations predicted poor prognosis in both TP53 mutant and wild-type LUSCs. We also found that in treated patients, FBXW7 and KEAP1 mutations were associated with poor response to adjuvant therapy, particularly in TP53-mutant tumors. Analysis of mutations with immune markers revealed that ADCY8 and PIK3CA mutations were associated with markedly decreased tumoral PD-L1 expression, LUSCs with PIK3CA mutations exhibited elevated CD45ro levels and CDKN2A-mutant tumors displayed an up-regulated immune response.

Conclusion(s)

Our findings pinpoint mutated genes that may impact clinical outcome as well as personalized strategies for targeted immunotherapies in early-stage LUSC.

Multivariate Entropy Characterizes the Gene Expression and Protein-Protein Networks in Four Types of Cancer

There is an important urgency to detect cancer at early stages to treat it, to improve the patients’ lifespans, and even to cure it. In this work, we determined the entropic contributions of genes in cancer networks. We detected sudden changes in entropy values in melanoma, hepatocellular carcinoma, pancreatic cancer, and squamous lung cell carcinoma associated to transitions from healthy controls to cancer. We also identified the most relevant genes involved in carcinogenic process of the four types of cancer with the help of entropic changes in local networks. Their corresponding proteins could be used as potential targets for treatments and as biomarkers of cancer.

Cell-free DNA and next-generation sequencing in the service of personalized medicine for lung cancer

Personalized medicine has emerged as the future of cancer care to ensure that patients receive individualized treatment specific to their needs. In order to provide such care, molecular techniques that enable oncologists to diagnose, treat, and monitor tumors are necessary. In the field of lung cancer, cell free DNA (cfDNA) shows great potential as a less invasive liquid biopsy technique, and next-generation sequencing (NGS) is a promising tool for analysis of tumor mutations. In this review, we outline the evolution of cfDNA and NGS and discuss the progress of using them in a clinical setting for patients with lung cancer. We also present an analysis of the role of cfDNA as a liquid biopsy technique and NGS as an analytical tool in studying EGFR and MET, two frequently mutated genes in lung cancer. Ultimately, we hope that using cfDNA and NGS for cancer diagnosis and treatment will become standard for patients with lung cancer and across the field of oncology.

Targeted depletion of PIK3R2 induces regression of lung squamous cell carcinoma

Oncogenic mutations in the PI3K/AKT pathway are present in nearly half of human tumors. Nonetheless, inhibitory compounds of the pathway often induce pathway rebound and tumor resistance. We find that lung squamous cell carcinoma (SQCC), which accounts for ~20% of lung cancer, exhibits increased expression of the PI3K subunit PIK3R2, which is at low expression levels in normal tissues. We tested a new approach to interfere with PI3K/AKT pathway activation in lung SQCC. We generated tumor xenografts of SQCC cell lines and examined the consequences of targeting PIK3R2 expression. In tumors with high PIK3R2 expression, and independently of PIK3CA, KRAS, or PTEN mutations, PIK3R2 depletion induced lung SQCC xenograft regression without triggering PI3K/AKT pathway rebound. These results validate the use PIK3R2 interfering tools for the treatment of lung squamous cell carcinoma.

Imaging genotyping of functional signaling pathways in lung squamous cell carcinoma using a radiomics approach

Imaging features can be useful for identifying distinct genomic differences and have predictive power for certain phenotypes attributed to genomic mutations. We aimed to identify predictive imaging biomarkers that underpin genomic alterations and clinical outcomes in lung squamous cell carcinoma (SQCC) using a radiomics approach. In 57 patients with lung SQCC who underwent preoperative computed tomography (CT) and whole-exome DNA sequencing, 63 quantitative imaging features were extracted from CT and 73 clinicoradiological features including imaging features were classified into 8 categories: clinical, global, histogram-based, lung cancer-specific, shape, local, regional, and emphysema. Mutational profiles for core signaling pathways of lung SQCC were classified into five categories: redox stress, apoptosis, proliferation, differentiation, and chromatin remodelers. Range and right lung volume was significantly associated with alternation of apoptosis and proliferation pathway (p = 0.03, and p = 0.03). Energy was associated with the redox stress pathway (p = 0.06). None of the clinicoradiological features showed any significant association with the alteration of differentiation and chromatin remodelers pathway. This study showed that radiomic features indicating five different functional pathways of lung SQCC were different form one another. Radiomics approaches to lung SQCC have the potential to noninvasively predict alterations in core signaling pathways and clinical outcome.

Circulating metabolite profiles to predict overall survival in advanced non-small cell lung cancer patients receiving first-line chemotherapy

OBJECTIVES

The prognosis for advanced-stage non-small cell lung cancer (NSCLC) is usually poor. However, survival may be variable and difficult to predict. In the current study, we aimed to identify circulating metabolites as potential predictive biomarkers for overall survival of advanced-stage (III/IV) NSCLC patients treated with first-line platinum-based chemotherapy.

MATERIALS AND METHODS

Using two-stage study design, we performed global metabolomic profiling in blood of 220 advanced-stage NSCLC patients, including 110 with poor survival and 110 with good survival. Metabolomic profiling was conducted using Metabolon platform. The association of each metabolite with survival was assessed by Cox proportional hazard regression model with adjustment for covariates.

RESULTS AND CONCLUSION

We found levels of 4 metabolites, caffeine, paraxanthine, stachydrine, and methyl glucopyranoside (alpha+beta), differed significantly between NSCLC patients with poor and good survival in both discovery and validation phases (P<0.05). Interestingly, majority of the identified metabolites are involved in caffeine metabolism, and 2 metabolites are related to coffee intake. In fact, caffeine metabolism pathway was the only significant pathway identified which significantly differed between NSCLC patients with poor and good survival (P=1.48E-07) in the pathway analysis. We also found 4 metabolites whose levels were significantly associated with good survival in both discovery and validation phases. Strong cumulative effects on overall survival were observed for these 4 metabolites. In conclusion, we identified a panel of metabolites including metabolites in caffeine metabolism pathway that may predict survival outcome in advanced-stage NSCLC patients. The identified small metabolites may be useful biomarker candidates to help identify patients who may benefit from platinum-based chemotherapy.

A three-microRNA signature for lung squamous cell carcinoma diagnosis in Chinese male patients

Various studies have demonstrated the diagnostic value of microRNA (miRNA) for lung cancer, but miRNA signatures varied between different subtypes. Whether serum miRNAs could be used as biomarkers in lung squamous cell carcinoma (SCC) remains unknown. Using quantitative real-time polymerase chain reaction (qRT-PCR) based Exiqon panel, 38 differentially expressed miRNAs were identified from 3 male lung SCC pool samples and 1 normal control (NC) pool in the initial screening phase. After the training (24 SCC VS. 15 NCs), testing (44 SCC VS. 57 NCs) and external validation (34 SCC VS. 36 NCs VS. 10 pulmonary hamartoma) processes via qRT-PCR, we identified a three-miRNA panel ((miR-106a-5p, miR-20a-5p and miR-93-5p) to be a potential diagnostic marker for male lung SCC patients. The areas under the receiver operating characteristic (ROC) curve of the three-miRNA panel for the training, testing and validation phases were 0.969, 0.881 and 0.954 respectively. In addition, this signature could also differentiate lung SCC from pulmonary hamartoma (AUC=0.900). The 3 miRNAs were consistently up-regulated in lung SCC tissues (23 SCC VS. 23 NCs) and serum exosomes (17 SCC VS. 24 NCs). Moreover, expression of the 3 miRNAs was decreased in arterial serum (n = 3). In conclusion, we established a three-miRNA signature in the peripheral serum with considerable clinical value in the diagnosis of male lung SCC patients.

Epigenetically silenced PTPRO functions as a prognostic marker and tumor suppressor in human lung squamous cell carcinoma

Protein tyrosine phosphatase receptor-type O (PTPRO), a member of the PTP family, has been frequently reported as potential tumor suppressor in many types of cancer. However, the exact function of PTPRO in lung squamous cell carcinoma (LSCC) remains unclear. Bisulfite sequencing and methylation specific polymerase chain reaction (PCR) were used to identify the methylation status of PTPRO in LSCC cells, and quantitative methylation specific PCR was used to evaluate the methylation levels of PTPRO in LSCC patients. Stably expressing PTPRO vectors were constructed and transfected into H520 and SK-MES-1 cells, followed by MTT and colony formation assays, and analysis of tumor weight and volume in in vivo mouse xenograft models. The present study demonstrated that the CpG island of PTPRO exon 1 was obviously hypermethylated in LSCC cells and tissues. The mRNA expression of PTPRO could be restored by treatment with a demethylation agent. Increased methylation and decreased mRNA levels of PTPRO were observed in LSCC samples compared with adjacent healthy tissues, and were associated with poor prognosis of patients. The mRNA expression of PTPRO was negatively correlated with its methylation level in tumors. Functionally, ectopic PTPRO expression in LSCC cells significantly inhibited the proliferation rates, and colony formation, in comparison with control and non-transfected cells. In vivo assays confirmed the inhibitory effect of PTPRO on LSCC cell growth. In conclusion, these data provided evidence that epigenetic regulation of PTPRO impairs its tumor suppressor role in LSCC, and restoration of PTPRO may be a potential therapeutic strategy.

New developments in the treatment of advanced squamous cell lung cancer: focus on afatinib

Until recently, few treatment options existed for the treatment of squamous cell carcinoma (SqCC) of the lung, especially in the second-line setting following platinum-based chemotherapy. Accordingly, outcomes in this subtype of non-small-cell lung cancer (NSCLC) were generally poor. In this context, the recent availability of the checkpoint inhibitors nivolumab and pembrolizumab, the anti-VEGFR2 antibody ramucirumab (combined with docetaxel), and the ErbB-family blocker afatinib for the treatment of relapsed/refractory SqCC of the lung represent major advances. However, the rapid expansion of the treatment armamentarium invites many questions regarding optimal treatment choice and sequence in individual patients. This review focuses on the biologic rationale and clinical evidence to support the use of afatinib in this treatment setting, highlighting the prominent role of the ErbB-signaling cascade in SqCC tumors. The seminal Phase III LUX-Lung 8 study, on which the approval of afatinib is based, is discussed and contextualized with the emergence of immunotherapies. Finally, criteria are explored that might drive physicians’ treatment decisions when considering the use of afatinib based on individual patient characteristics. Other ongoing developments in the treatment of SqCC of the lung that will lead to further options and welcome improvements in the management of this difficult-to-treat disease are summarized.

[Altered Treg and IL-1A Expression in the Immune Microenvironment of Lung Squamous-cell Cancer after EGFR Blockade]

背景与目的

精确靶向表皮生长因子受体（epidermal growth factor receptor, EGFR）的治疗在肺鳞癌、口腔和肠胃癌中取得了一定疗效，但会引发系统性炎症。本实验旨在探究EGFR抑制剂治疗癌引发的肿瘤内部免疫变化。

方法

我们通过含H-ras基因逆转录病毒转染EGFR基因缺失或野生型小鼠角质细胞，将改造的细胞同源移植至小鼠以成瘤，吉非替尼治疗荷瘤小鼠，流式细胞仪检测T细胞比例与程序性死亡受体1（programmed death 1, PD-1）表达，RT-PCR检测细胞因子与趋化因子的表达。

结果

敲除EGFR基因形成的肿瘤较野生型小，并且肿瘤微环境中浸润FoxP3+调节性T细胞（regulatory cells, Treg）细胞较少，FoxP3 RNA较少，程序性死亡受体1（programmed death 1, PD-1）阳性CD4⁺细胞比例降低。表明肿瘤细胞可以自主调节肿瘤微环境。野生型成瘤模型使用吉非替尼治疗1周显示，相对于对照组肿瘤较小；在这短期的药理模型中，同样观察到FoxP3+细胞、FoxP3 RNA减少的趋势，同时IL-1A/IL-1RA比例明显升高，表明相对短暂的系统性抑制EGFR信号通路可改变靶向肿瘤的免疫微环境。

结论

肿瘤细胞自发（基因）或系统性（药理作用）的抑制EGFR信号通路可减少肿瘤的生长和肿瘤微环境中Treg的渗透。EGFR依赖性Treg细胞增强肺鳞癌的生长，是EGFR抑制剂治疗的靶标。

A piRNA-like Small RNA Induces Chemoresistance to Cisplatin-Based Therapy by Inhibiting Apoptosis in Lung Squamous Cell Carcinoma

Lung cancer is the leading cause of cancer-related death worldwide. Although advanced drugs have benefitted patients, therapeutic success has largely been hampered because of rapid development of resistance. Here we report that PIWI-interacting RNA likes (piR-Ls), a novel type of functional sncRNAs, play key roles in chemoresistance to cisplatin (CDDP)-based chemotherapy in lung squamous cell carcinoma (LSCC). piR-L-138 was upregulated upon CDDP-based chemotherapy both in LSCC cells and in patient-derived xenograft (PDX) LSCC models. Further, targeting upregulated piR-L-138 led to increased apoptosis in CDDP-treated LSCC cells and LSCC xenograft mice treated with CDDP. In addition, piR-L-138 directly interacted with p60-MDM2 and inhibited CDDP-activated apoptosis in p53-mutated LSCC. We identified the upregulated piR-L-138 upon CDDP-based chemotherapy, confirmed the enhanced sensitivity of LSCC to agents by targeting the upregulated piR-L-138 both in vitro and in vivo, and revealed mechanisms underlying piR-L-138 in chemoresistance, bolstering a new emerging clinical modality where novel functional piR-Ls provide potential strategies to overcome chemoresistance for patients with LSCC.

PD-L1+MDSCs are increased in HCC patients and induced by soluble factor in the tumor microenvironment

Myeloid-derived suppressor cells (MDSCs) could have important roles in immune regulation, and MDSCs can be induced in patients with various malignant tumors. The immune-suppressive functions of MDSCs in hepatocellular carcinoma (HCC) patients have not been clarified. Therefore, we tried to analyze the biological significance of MDSCs in HCC patients. We quantified PD-L1⁺MDSCs of HCC patients in various conditions by using multi-color flow cytometry analysis. PBMCs from HCC patients contained significantly higher percentages of PD-L1⁺MDSCs in comparison to those from healthy subjects (p < 0.001). The percentages of PD-L1⁺MDSCs were reduced by curative treatment for HCC (p < 0.05), and the percentages of PD-L1⁺MDSCs before treatment were inversely correlated with disease-free survival time. After we cocultivated PBMCs and several liver cancer cell lines in a transwell coculture system, the percentages of PD-L1⁺MDSCs were significantly increased compared with control (p < 0.05). The expression of M-CSF and VEGFA was higher in the cell lines that strongly induced PD-L1⁺MDSCs. Peripheral blood from HCC patients had significantly higher percentages of PD-L1⁺MDSCs in comparison to those of healthy subjects, and the percentages of PD-L1⁺MDSCs were reduced by HCC treatment, suggesting that we might use PD-L1⁺MDSCs as a new biomarker of HCC.

Influence of MDM2 polymorphisms on squamous cell carcinoma susceptibility: a meta-analysis

PURPOSE

Controversial associations between single-nucleotide polymorphisms (rs2279744, rs937283, rs3730485) of the MDM2 gene and the etiology of squamous cell carcinomas (SCCs) have been reported. This merits further comprehensive assessment.

MATERIALS AND METHODS

We systematically reviewed the available data and conducted an updated meta-analysis to evaluate the genetic effect of MDM2 polymorphisms in SCC susceptibility, using Stata/SE 12.0 software.

RESULTS

After screening, 7,987 SCC cases and 12,954 controls from 26 eligible case-control studies were enrolled. Overall, compared with the control group, a significantly increased SCC risk was observed for the MDM2 rs2279744 polymorphism in the Asian population (test of association: odds ratio [OR] 1.12, P=0.027 for G vs T; OR 1.26, P=0.016 for GG vs TT; OR 1.25, P<0.001 for GG vs TT + TG; and OR 1.08, P=0.023 for carrier G vs T). In subgroup analysis by SCC type, a similarly increased esophageal SCC risk was detected (OR 1.19, P<0.001 for G vs T; OR 1.46, P<0.001 for GG vs TT; and OR 1.48, P=0.005 for GG vs TT + TG). Furthermore, MDM2-TP53 double mutation was statistically associated with increased SCC susceptibility overall (OR 1.52, P=0.001), especially in the Asian population (OR 1.49, P=0.022). However, no significant difference between the control and case groups was obtained for MDM2 rs937283 or rs3730485 under any genetic model (all P>0.05).

CONCLUSION

Our results highlight a positive association between the GG genotype of MDM2 rs2279744 polymorphism and an increased risk of esophageal SCC in the Asian population, which needs to be clarified by more large-scale studies.

Deguelin Induces the Apoptosis of Lung Squamous Cell Carcinoma Cells through Regulating the Expression of Galectin-1

Lung cancer is the leading cause of cancer mortality around the world. Despite advances in the targeted therapy, patients with lung squamous cell carcinoma(SCC) still benefit few from it, and the search for potential effective therapies is imperative. Here, we demonstrated that deguelin induced significant apoptosis of lung SCC cells in vitro. Importantly, we found deguelin down-regulated the expression of galectin-1, which was involved in a wide range of tumorous physiologic process. Thus, we both over-expressed and down-regulated galectin-1 to perform its role in deguelin-induced apoptosis. We found that increased galectin-1 attenuated apoptosis of SCC cells exposed to deguelin, while galectin-1 knockdown sensitized lung cancer cells to deguelin treatment. Additionally, we observed that down-regulation of galectin-1 resulted in suppression of Ras/Raf/ERK pathway which was involved in deguelin-induced cell apoptosis. We also found that deguelin had a significant anti-tumor ability with decline of galectin-1 in vivo. In conclusion, these findings confirm that deguelin may act as a new chemo-preventive agent through inducing apoptosis of lung SCC cells in a galectin-1 dependent manner.

Spotlight on afatinib and its potential in the treatment of squamous cell lung cancer: the evidence so far

Compared to adenocarcinoma, fewer effective treatment options are available for advanced or metastatic squamous cell carcinoma (SCC) of the lung. Afatinib is an orally administered, irreversible EGFR antagonist. As a second-generation tyrosine kinase inhibitor, it has been applied in the treatment of patients with EGFR-mutant non-small-cell lung cancer. Recently, several clinical trials have shown that afatinib leads to a significant improvement in progression-free survival and overall survival of patients with SCC. Moving forward, afatinib should be one of the options among tyrosine kinase inhibitors, monoclonal antibodies, and cytotoxicity chemotherapy drugs for SCC.