Squamous cell lung cancer: Current landscape and future therapeutic options

Role of COL5A1 in lung squamous cell Carcinoma: Prognostic Implications and therapeutic potential

BACKGROUND

Lung squamous cell carcinoma (LUSC) is a significant health concern, characterized by a lack of specific therapies and limited treatment options for patients in advanced stages. This study aims to identify key molecules of prognostic importance in LUSC and provide an experimental foundation for their potential therapeutic applications.

METHODS

Immune-related transcriptome expression analysis was performed on LUSC samples using the NanoString digital gene analysis system to develop a prognostic transcriptomic signature. This was followed by validation within the LUSC cohort database, and the immune properties and cellular functions of the critical molecule were examined through molecular biology experiments.

RESULTS

Advanced nCounter analysis revealed significant differences in the numbers of T cells, cytotoxic cells, B cells, and CD45+ and CD8+ T cells between the OS1 (short-term survival) group and the OS2 (long-term survival) group. A comparison of the differences in tumor immune-related pathways between the two groups revealed that signaling pathways such as the PI3K-AKT, NF-kappaB signaling, Notch signaling, angiogenesis, matrix remodeling, and metastasis pathways were activated in the OS1 subgroup, and DNA damage repair and lymphatic chamber signaling pathways were activated in the OS2 subgroup. We analyzed and compared differentially expressed mRNAs with high expression levels in the OS1 and stage IV groups. Collagen type V alpha 1 (COL5A1) was found to be associated with the prognosis of LUSC. Phenotypic analysis revealed that COL5A1 knockdown inhibited the proliferation, migration, and invasion of SKMES1 cells. Locating COL5A1 was shown to be expressed in CAFs, T cells, and EPI cells through single-cell omics analysis.

CONCLUSION

COL5A1 plays a crucial role in tumor progression, indicating that COL5A1 inhibitors may represent a promising therapeutic strategy for the treatment of LUSC.

High circulating activin A plasma levels are associated with tumour stage and poor survival in treatment-naive lung squamous cell cancer patients

OBJECTIVES

Lung squamous cell carcinoma (LUSC) is associated with a poor prognosis and a lack of specific treatment options. The dysregulation of activin A (ActA) has been reported in various malignancies. Herein, we investigated the diagnostic and prognostic significance of ActA in LUSC.

MATERIALS AND METHODS

ActA concentrations were measured using ELISA in plasma samples of 128 LUSC patients (stage I-IV) and 73 controls, and correlated those values with clinicopathological parameters and survival.

RESULTS

ActA plasma levels were significantly higher in therapy-naive LUSC patients compared to controls (444.1 ± 310.9 pg/mL vs 338.9 ± 145.5 pg/mL, p = 0.010). ActA levels significantly correlated with advanced stage as well as with T and N factors. High circulating ActA levels were significantly increased in metastatic disease patients compared to M0 disease. Further, patients with ActA levels above a computationally established optimal cut-off value of 443.0 pg/mL had a significantly worse median overall (OS, 17.63 vs 64.77 months, HR 0.391, 95 % CI 0.200-0.762, p < 0.001) and median disease-/progression-free survival (DFS/PFS; 11.57 vs 30.20 months, HR 0.502, 95 % CI 0.248-1.019, p = 0.020). Multivariate analysis revealed that high ActA levels were an independent prognostic factor for shorter OS (p = 0.001) and DFS/PFS (p = 0.018). A newly developed score combining CRP and ActA levels was also an independent prognostic factor for OS and DFS/PFS.

CONCLUSION

Measurement of circulating ActA levels may help identify advanced-stage LUSC patients, and this value could serve as a prognostic parameter in LUSC. Thus, ActA may be a novel blood-based biomarker for identifying LUSC patients with distant metastasis.

Causal relationship between gut microbiota and lung squamous cell carcinoma: a bidirectional two-sample Mendelian randomization study

PURPOSE

This study aims to explore the potential causal relationship between gut microbiota and lung squamous cell carcinoma (LUSC).

METHODS

A bidirectional two-sample Mendelian randomization analysis was conducted using genome-wide association study (GWAS) data from gut microbiota and LUSC. Gut microbiota served as the exposure factor, with instrumental variables selected from a GWAS involving 18 340 participants. LUSC data were drawn from a European cohort including 29 266 LUSC cases and 56 450 controls. Inverse-variance weighted (IVW) method was used as the primary method, with the Benjamini-Hochberg method applied to adjust for multiple comparisons. An independent dataset (ieu-a-967, containing 3275 LUSC cases and 15 038 controls) was used for replication analysis to ensure robustness.

RESULTS

IVW analysis found that Butyricicoccus (OR = 0.79, 95% CI: 0.63-0.99, P = .042) and Coprobacter (OR = 0.85, 95% CI: 0.74-0.97, P = .018) were significantly protective against LUSC. In contrast, Victivallis (OR = 1.11, 95% CI: 1.00-1.23, P = .045) and Ruminococcus (OR = 1.28, 95% CI: 1.03-1.60, P = .028) increased LUSC risk. Replication analysis in the independent dataset confirmed significant associations for Ruminococcus and Coprobacter. No reverse causality or pleiotropy was detected.

CONCLUSION

This study provides evidence of a causal relationship between specific gut microbiota and LUSC risk, highlighting new microbial targets for potential prevention and treatment strategies in lung cancer. Key messages What is already known on this topic?  Previous studies have suggested potential links between gut microbiota composition and the development of various cancers, including lung cancer. However, the exact causal relationship between specific gut microbiota and lung squamous cell carcinoma (LUSC) has remained unclear. Traditional observational studies have struggled to determine the direction of causality due to confounding factors, making further investigation necessary through more robust methods such as Mendelian randomization (MR). What this study adds?  This bidirectional MR study provides novel genetic evidence indicating that certain gut microbiotas are causally associated with LUSC risk. Specifically, Butyricicoccus appears to reduce the risk of LUSC, while Victivallis increases the risk. These findings highlight the role of the gut-lung axis in LUSC and open up new avenues for exploring gut microbiota as potential modulators of lung cancer risk. How this study might affect research, practice, or policy?  The implications of this study may significantly influence future research into cancer prevention strategies by targeting gut microbiota. Additionally, it could inform clinical practices aimed at modulating gut microbiota to lower the risk of LUSC, potentially influencing dietary or probiotic interventions to reduce cancer susceptibility. Furthermore, these results might shape public health policies that focus on the gut-lung axis as a novel avenue for cancer prevention and management.

PIK3CA Mutations and Co-Mutations in Operated Non-Small Cell Lung Carcinoma

Background: Understanding PIK3CA mutations and co-mutations in non-small cell lung carcinoma (NSCLC) is critical to developing personalized treatment strategies. Therefore, this study aims to investigate PIK3CA mutations and the accompanying somatic variations in NSCLC. Methods: This retrospective study included 98 patients over 18 years of age who were diagnosed with NSCLC, operated on, and referred to the Molecular Pathology Laboratory between January 2019 and June 2024 for next-generation sequencing panel tests and ALK-ROS1 FISH analysis. Results: All patients were found to carry PIK3CA mutations. Among the 98 NSCLC patients analyzed, 16 (16.33%) were female and 82 (83.67%) were male. The average age of the patients was 64.53 ± 9.63 years, with an age range of 38-84 years, and the majority were 50 years or older. Of the cases, 51 presented the adenocarcinoma subtype, while the remaining 47 showed the squamous cell carcinoma subtype. A smoking history was present in 77 (78.57%) patients, while 21 (21.43%) had no smoking history. The most frequently detected pathogenic or likely pathogenic PIK3CA variations were c.1633G>A p.E545K (32.65%), c.1624G>A p.E542K (11.22%), c.3140A>G p.H1047R (11.22%), c.3140A>T p.H1047L (5.10%), c.1357G>C p.E453Q (4.08%), and c.3143A>G p.H1048R (2.04%). The top 10 mutations that most commonly accompanied PIK3CA variations were KRAS, NF1, TP53, EGFR, PTEN, BRAF, KIT, CDKN2A, SMARCA4, and ATM mutations, respectively. Conclusions:PIK3CA variations, along with other gene variations, may influence cancer progression and thus may play a crucial role in the determination of targeted treatment strategies.

Reactive oxygen species control protein degradation at the mitochondrial import gate

While reactive oxygen species (ROS) have long been known to drive aging and neurodegeneration, their persistent depletion below basal levels also disrupts organismal function. Cells counteract loss of basal ROS via the reductive stress response, but the identity and biochemical activity of ROS sensed by this pathway remain unknown. Here, we show that the central enzyme of the reductive stress response, the E3 ligase Cullin 2-FEM1 homolog B (CUL2FEM1B), specifically acts at mitochondrial TOM complexes, where it senses ROS produced by complex III of the electron transport chain (ETC). ROS depletion during times of low ETC activity triggers the localized degradation of CUL2FEM1B substrates, which sustains mitochondrial import and ensures the biogenesis of the rate-limiting ETC complex IV. As complex III yields most ROS when the ETC outpaces metabolic demands or oxygen availability, basal ROS are sentinels of mitochondrial activity that help cells adjust their ETC to changing environments, as required for cell differentiation and survival.

Lung-MAP Next-Generation Sequencing Analysis of Advanced Squamous Cell Lung Cancers (SWOG S1400)

INTRODUCTION

Squamous cell cancer (SqCC) is a lung cancer subtype with few targeted therapy options. Molecular characterization, that is, by next-generation sequencing (NGS), is needed to identify potential targets. Lung Cancer Master Protocol Southwest Oncology Group S1400 enrolled patients with previously treated stage IV or recurrent SqCC to assess NGS biomarkers for therapeutic sub-studies.

METHODS

Tumors underwent NGS using Foundation Medicine's FoundationOne research platform, which sequenced the exons and/or introns of 313 cancer-related genes. Mutually exclusive gene set analysis and Selected Events Linked by Evolutionary Conditions across Human Tumors were performed to identify mutually exclusive and co-occurring gene alterations. Comparisons were performed with data on 495 lung SqCC downloaded from The Cancer Genome Atlas. Cox proportional hazards models were used to assess associations between genetic variants and survival.

RESULTS

NGS data are reported for 1672 patients enrolled on S1400 between 2014 and 2019. Mutually exclusive gene set analysis identified two non-overlapping sets of mutually exclusive alterations with a false discovery rate of less than 15%: NFE2L2, KEAP1, and PARP4; and CDKN2A and RB1. PARP4, a relatively uncharacterized gene, showed three frequent mutations suggesting functional significance: 3116T>C (I1039T), 3176A>G (Q1059R), and 3509C>T (T1170I). When taken together, NFE2L2 and KEAP1 alterations were associated with poorer survival.

CONCLUSIONS

As the largest dataset to date of lung SqCC profiled on a clinical trial, the S1400 NGS dataset establishes a rich resource for biomarker discovery. Mutual exclusivity of PARP4 and NFE2L2 or KEAP1 alterations suggests that PARP4 may have an uncharacterized role in a key pathway known to impact oxidative stress response and treatment resistance.

Lymph node metastasis prediction from in-situ lung squamous cell carcinoma histopathology images using deep learning

Lung squamous cell carcinoma (LUSC), a subtype of non-small cell lung cancer, represents a significant portion of lung cancer cases with distinct histologic patterns impacting prognosis and treatment. The current pathological assessment methods face limitations such as inter-observer variability, necessitating more reliable techniques. This study seeks to predict lymph node metastasis in LUSC using deep learning models applied to histopathology images of primary tumors, offering a more accurate and objective method for diagnosis and prognosis. Whole slide images (WSIs) from the Outdo-LUSC and TCGA-LUSC cohorts were used to train and validate deep-learning models. Multi-instance learning was applied, with patch-level predictions aggregated into WSI-level outcomes. The study employed the ResNet-18 network, transfer learning, and rigorous data preprocessing. To represent WSI features, innovative techniques like patch likelihood histogram (PLH) and bag of words (BoW) were used, followed by training of machine learning classifiers, including the ExtraTrees algorithm. The diagnostic model for lymph node metastasis showed strong performance, particularly using the ExtraTrees algorithm, as demonstrated by receiver operating characteristic (ROC) curves and Grad-CAM visualizations. The signature generated by the ExtraTrees algorithm, named LN_ISLUSCH (lymph node status-related in-situ lung squamous cell carcinoma histopathology), achieved an area under the curve (AUC) of 0.941 (95% CI: 0.926-0.955) in the training set and 0.788 (95% CI: 0.748-0.827) in the test set. Kaplan-Meier analyses confirmed that the LN_ISLUSCH model was a significant prognostic factor (p = 0.02). This study underscores the potential of artificial intelligence in enhancing diagnostic precision in pathology. The LN_ISLUSCH model stands out as a promising tool for predicting lymph node metastasis and prognosis in LUSC. Future studies should focus on larger and more diverse cohorts and explore the integration of additional omics data to further refine predictive accuracy and clinical utility.

IGF2BP3/CTCF Axis-Dependent NT5DC2 Promotes M2 Macrophage Polarization to Enhance the Malignant Progression of Lung Squamous Cell Carcinomas

BACKGROUND

Lung squamous cell carcinoma (LUSC) is a type of lung cancer that develops in the squamous cells. It is known to be promoted by the activation of various signaling pathways and the dysregulation of key regulatory molecules. One such molecule, 5'-nucleotidase domain containing 2 (NT5DC2), has been identified as a critical regulator in various cancers including lung cancer. However, there are no data regarding its role in LUSC.

METHODS

The mRNA expression of insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3), CCCTC-binding factor (CTCF), and NT5DC2 was analyzed using quantitative real-time polymerase chain reaction (qRT-PCR), whereas their protein expression was assessed using a western blotting assay. Cell proliferation was determined using a cell counting kit-8 (CCK-8) assay. Cell apoptosis, CD11b expression, and CD206 expression were analyzed using flow cytometry. Tube formation was assessed through a tube formation assay. Glucose consumption, lactate production, and ATP levels were measured using colorimetric methods. The effect of NT5DC2 on the malignant progression of LUSC cells was analyzed using a xenograft mouse model assay. The levels of transforming growth factor-beta 1 (TGF-β1) and interleukin-10 (IL-10) were detected using enzyme-linked immunosorbent assays. The associations among IGF2BP3, CTCF and NT5DC2 were identified using dual-luciferase reporter assay, RNA immunoprecipitation assay and m6A RNA immunoprecipitation assay.

RESULTS

The expression of NT5DC2 was found to be upregulated in LUSC tissues and cells when compared with normal lung tissues and normal human bronchial epithelial cells. Silencing of NT5DC2 inhibited LUSC cell proliferation, tube formation, glycolysis, M2 macrophage polarization, and tumor formation while inducing cell apoptosis. In addition, CTCF was found to transcriptionally activate NT5DC2 in LUSC cells. IGF2BP3 stabilized the mRNA expression of CTCF through m6A methylation. Further, overexpression of CTCF or NT5DC2 attenuated the effects of IGF2BP3 silencing in both NCI-520 and SK-MES-1 cells.

CONCLUSION

The IGF2BP3/CTCF axis-dependent NT5DC2 promotes M2 macrophage polarization, thereby enhancing the malignant progression of LUSC. This study was the first to reveal the role of NT5DC2 in LUSC and the underlying mechanism. The result suggests that targeting the IGF2BP3/CTCF/NT5DC2 axis may have clinical significance in the treatment of LUSC.

Natural Killer Cells in Cancers of Respiratory System and Their Applications in Therapeutic Approaches

BACKGROUND

Cancer is still regarded as a major worldwide health issue due to its high health and socioeconomic burden. Currently, lung cancer is the most common cause of cancer-related fatalities globally. Additionally, mesotheliomas and other cancers of the respiratory system, including those of the trachea, larynx, and bronchi, are also posing a significant health threat. Natural killer (NK) cells are lymphocytes of the innate immune system involved in response against cancer.

OBJECTIVE

This review discussed recent findings in the context of NK cell activity in the immune surveillance of respiratory system cancers and NK cell-based treatments to combat those malignancies.

RESULTS

The presence of natural killer cells in the tumor microenvironment is shown to be associated with a higher survival rate in patients with various malignancies. However, cancerous cells benefit from several mechanisms to evade natural killer cell-mediated cytotoxicity, including reduced major histocompatibility complex I expression, shedding of ligands, upregulation of inhibitory receptors, and release of soluble factors. Using NK cells to design therapeutic approaches may enhance antitumor immunity and improve clinical outcomes. Clinical trials investigating the use of natural killer cells in combination with cytokine stimulation or immune checkpoint inhibitors have exhibited promising results in various respiratory system malignancies.

CONCLUSION

Respiratory system cancers present significant health challenges worldwide, and while NK cells play a crucial role in tumor surveillance, tumors often evade NK cell responses through various mechanisms. Advances in NK cell-based therapies, including CAR-NK cells, immune checkpoint inhibitors, and cytokine stimulation, have shown promising outcomes in tackling these tactics. However, challenges such as the immunosuppressive tumor microenvironment persist. Ongoing research is crucial to improve NK cell therapies by targeting autophagy, modulating miRNAs, and developing combinatorial approaches to enhance treatment efficacy for respiratory cancers.

Landscape of targeted therapies for lung squamous cell carcinoma

Lung cancer, a common type of malignant neoplasm, has seen significant advancements in the treatment of lung adenocarcinoma (LUAD). However, the management of lung squamous cell carcinoma (LSCC) continues to pose challenges. Traditional treatment methods for LSCC encompass surgical resection, chemotherapy, and radiotherapy. The introduction of targeted therapy and immunotherapy has greatly benefited LSCC patients, but issues such as limited immune response rates and adverse reactions persist. Therefore, gaining a deeper comprehension of the underlying mechanisms holds immense importance. This review provides an in-depth overview of classical signaling pathways and therapeutic targets, including the PI3K signaling pathway, CDK4/6 pathway, FGFR1 pathway and EGFR pathway. Additionally, we delve into alternative signaling pathways and potential targets that could offer new therapeutic avenues for LSCC. Lastly, we summarize the latest advancements in targeted therapy combined with immune checkpoint blockade (ICB) therapy for LSCC and discuss the prospects and challenges in this field.

Exploring the prognostic and therapeutic value of HIF1A in lung adenocarcinoma

Lung adenocarcinoma (LUAD) remains a challenge within the realm of non-small cell lung cancer (NSCLC), demanding innovative diagnostic and therapeutic solutions. In this study, we systematically detected the correlation between the expression of hypoxia-induced factor 1A (HIF1A) and the clinical characteristics of LUAD, alongside lung squamous cell carcinoma (LUSC). Our bioinformatic analysis reveals that HIF1A mRNA expression is significantly upregulated in both LUAD and LUSC samples compared to non-tumorous lung tissues. The overexpression is positively correlated with increased copy number variation and negatively associated with promoter methylation. However, meta-analysis and survival analyses revealed a pronounced association between elevated HIF1A expression and poor clinical outcome specifically within the LUAD subset, with no such correlation evident in LUSC. Additionally, we explored the interplay between HIF1A expression, leukocyte infiltration, and the presence of immunosuppressive markers, revealing HIF1A's suppressive role in cytotoxicity against cancer cells. Furthermore, we performed in silico prediction to explore the correlations between HIF1A and its interacting proteins, associated pathways, glycolysis, and m6A modification, and the feasibility of targeting HIF1A with specific drugs. In summary, our study revealed the prognostic significance and therapeutic potential of HIF1A in LUAD.

Wee1 inhibitor PD0166285 sensitized TP53 mutant lung squamous cell carcinoma to cisplatin via STAT1

BACKGROUND

Lung squamous cell carcinoma (LUSCs) is associated with high mortality (20-30%) and lacks of effective treatments. Almost all LUSC exhibit somatic mutations in TP53. Wee1, a tyrosine kinase, regulates the cell cycle at the G2/M checkpoint. In TP53-deficient cells, the dependence on G2/M checkpoints increases. PD0166285 is the first reported drug with inhibitory activity against both Wee1 and PKMYT1.

METHODS

Protein expression was determined by Western blot analysis. Cell proliferation was assessed using cell colony formation and CCK-8 assays. Cell cycle was performed by PI staining with flow cytometry. Apoptosis was evaluated using Annexin V-Phycoerythrin double staining and flow cytometry. DNA damage was detected through comet assay and immunofluorescence assay. In vivo, apoptosis and anti-tumor effects were assessed using the TUNEL assay, a nude mouse model, and immunohistochemistry (IHC). Co-immunoprecipitation assay was used to detect protein-protein interactions. We analyzed Wee1, PKMYT1, and Stat1 expression in pan-cancer studies using the Ualcan public database and assessed their prognostic implications with Kaplan-Meier curves.

RESULT

PD0166285, a Wee1 inhibitor, effectively inhibits Wee1 activity, promoting cell entry into a mitotic crisis. Moreover, PD0166285 sensitizes cells to cisplatin, enhancing clinical outcomes. Our study demonstrated that PD016628 regulates the cell cycle through Rad51 and results in cell cycle arrest at the G2/M phase. We observed increased apoptosis in tumor cells treated with PD0166285, particularly when combined with cisplatin, indicating an enhanced apoptotic response. The upregulation of γ-H2AX serves as an indicator of mitotic catastrophe. Co-immunoprecipitation and data analysis revealed that apoptosis in LUSC is mediated through the Stat1 pathway, accompanied by decreased levels of Socs3. Furthermore, IHC staining confirmed significant differences in the expression of Phospho-CDK1 and γ-H2AX in LUSCs, suggesting involvement in DNA damage.

CONCLUSIONS

In summary, our study suggests that PD0166285, an inhibitor of Wee1, sensitizes LUSC cells to cisplatin and modulates DNA damage and apoptosis pathways through Rad51 and Stat1, respectively. These findings highlight the combination of PD0166285 and cisplatin as a promising therapeutic approach for treating LUSC.

Toosendanin Induces Lung Squamous Cell Carcinoma Cell Apoptosis and Inhibits Tumor Progression via the BNIP3/AMPK Signaling Pathway

Lung squamous cell carcinoma (LUSC) is the second most common type of non-small cell lung cancer. Toosendanin can target critical cancer cell survival and proliferation. However, the function of toosendanin in LUSC is limited. Cancer cell proliferative capacity is detected using cell morphology, colony formation, and flow cytometry. The invasiveness of the cells is detected by a Transwell assay, western blotting, and RT-qPCR. Nude mice are injected with H226 (1×106) and received an intraperitoneal injection of toosendanin every 2 days for 21 days. RNA sequence transcriptome analysis is performed on toosendanin-treated cells to identify target genes and signaling pathways. With increasing concentrations of toosendanin, the rate of cell proliferation decreases and apoptotic cells increases. The number of migrated cells significantly reduces and epithelial-mesenchymal transition is reversed. Injection of toosendanin in nude mice leads to a reduction in tumor volume, weight, and the number of metastatic tumors. Furthermore, KEGG shows that genes related to the AMPK pathway are highly enriched. BNIP3 is the most differentially expressed gene, and its expression along with phosphorylated-AMPK significantly increases in toosendanin-treated cells. Toosendanin exerts anticancer effects, induces apoptosis in LUSC cells, and inhibits tumor progression via the BNIP3/AMPK signaling pathway.

Effects of 630 nm laser on apoptosis, metastasis, invasion and epithelial-to-mesenchymal transition of human lung squamous cell carcinoma H520 cells mediated by hematoporphyrin derivatives

Photodynamic therapy (PDT) has significant advantages in the treatment of malignant lung tumors. The research on the mechanism of PDT mediated by hematoporphyrin derivatives (HPD) and its cytotoxic effects on lung cancer cells has primarily focused on lung adenocarcinoma cells. However, the impact of HPD-PDT on lung squamous cell carcinoma has not been thoroughly studied. This study aimed to investigate the effects of 630 nm laser on apoptosis, metastasis, invasion, and epithelial-mesenchymal transition (EMT) in human lung squamous cell carcinoma H520 cells mediated by HPD. H520 cells were divided into four groups: control group, photosensitizer group, irradiation group, and HPD-PDT group. Cell proliferation was assessed using CCK8 assay; cell apoptosis was detected by Hoechst 33258 staining and flow cytometry; cell migration and invasion abilities were evaluated using wound-healing and invasion assays; and protein and mRNA expressions were analyzed by Western blot and reverse transcription-polymerase chain reaction (RT-PCR) respectively. Results showed that HPD-PDT significantly inhibited cell proliferation, promoted apoptosis (P < 0.05), suppressed cell migration and invasion (P < 0.05), decreased Bcl-2 mRNA expression, and increased Bax and Caspase-9 mRNA expression(P < 0.05). Western blotting analysis indicated increased expression of Bax, Caspase-9, and E-cadherin, and decreased expression of Bcl-2, N-cadherin, and Vimentin (P < 0.05). In conclusion, 630 nm laser mediated by HPD promoted cell apoptosis via upregulation of Bax and caspase-9, and downregulation of Bcl-2, and inhibited cell migration and invasion by regulating EMT in H520 cells.

Opposing Functions of Maspin Are Regulated by Its Subcellular Localization in Lung Squamous Cell Carcinoma Cells

Mammary serine protease inhibitor (maspin) is a tumor suppressor protein downregulated during carcinogenesis and cancer progression; cytoplasmic-only maspin expression is an independent, unfavorable prognostic indicator in patients with lung squamous cell carcinoma (LUSC). We hypothesized that the cytoplasmic-only localization of maspin has tumor-promoting functions in LUSC. The subcellular localization of maspin and the invasive capability of LUSC cell lines were investigated using RNA sequencing (RNA-seq), Western blotting, and siRNA transfection. Maspin mRNA and protein expression were suppressed in LK-2 and RERF-LC-AI cells. Cell invasion significantly increased in response to siRNA-mediated maspin knockdown in KNS-62 cells expressing both nuclear and cytoplasmic maspin. In LK-2 cells, both nuclear and cytoplasmic maspin were re-expressed, and cell invasion and migration were significantly decreased. In contrast, re-expressed maspin in RERF-LC-AI cells was detected only in the cytoplasm (cytMaspin), and cell invasion and migration were significantly promoted. RNA-seq and downstream analyses revealed that increased cytMaspin expression downregulated the genes associated with cell adhesion and activated PYK2 and SRC, which play important roles in cancer progression. Our study demonstrates a novel biological function of cytMaspin in enhancing the invasive capabilities of LUSC cells. Understanding cytoplasm-to-nuclear maspin translocation dysregulation may develop novel therapeutic approaches to improve the prognosis of patients with LUSC.

Unveiling potential drug targets for lung squamous cell carcinoma through the integration of druggable genome and genome-wide association data

Background: Lung squamous cell carcinoma (LSCC) is a major subtype of lung cancer with poor prognosis and low survival rate. Compared with lung adenocarcinoma, yet no FDA-approved targeted-therapy has been found for lung squamous cell carcinoma. Methods: To identify potential drug targets for LSCC, Summary-data-based Mendelian randomization (SMR) analysis was used to examine the potential association between 4,543 druggable genes and LSCC, followed by colocalization analysis and HEIDI tests to confirm the robustness of the result. Phenome-wide association study (PheWAS) explored potential side effects of candidate drug targets. Enrichment analysis and protein-protein interaction networks revealed the function and significance of therapeutic targets. Single-cell expression analysis was used to examine cell types with enrichment expression of druggable genes in LSCC tissue. Drug prediction included screening potential drug candidates and evaluating their interactions with targets through molecular docking. Results: This research has identified ten significant drug targets for LSCC through a comprehensive SMR analysis. These targets included (COPA, PKD2L1, CCR1, C2, CYP21A2, and NCSTN as risk factors, and CCNA2, C4A, APOM, and LPAR2 as protective factors). PheWAS demonstrated that C2, CCNA2, LPAR2, and NCSTN exhibited associations with other phenotypes at the genetic level. Then, we found four potentially effective drugs with the Dsigdb database. Subsequently, molecular docking indicated that favorable binding interactions between drug candidates and potential target molecules. In the druggability evaluation, five out of ten drug target genes have been used in drug development (APOM, C4A, CCNA2, COPA, and PKD2L1). Six out of ten druggable genes showed significant expression in LSCC tissues (COPA, PKD2L1, CCR1, C2, NCSTN, LPAR2). Besides, Single-cell expression analysis revealed that C2 and CCNA2 were primarily enriched in macrophages, while COPA and NCSTN were enriched in both macrophages and epithelial cells. Conclusion: Our research revealed ten potential druggable genes for LSCC treatment, which might help to advance the precise and efficient therapeutic approaches of LSCC.

Toll-like Receptors: Key Players in Squamous Cell Carcinoma Progression

Background/Objectives Lung squamous cell carcinoma (SCC) is one of the major subtypes of lung cancer, characterized by diverse molecular pathways and variable clinical outcomes. This study focused on assessing the levels of TLR-2, TLR-3, TLR-4, TLR-7, TLR-8, and TLR-9 on peripheral blood lymphocytes in patients with newly diagnosed SCC compared to a group of healthy controls, in the context of disease development and patient survival, conducted over three years. The study aimed to investigate the differences in TLR expression between SCC patients and healthy people and to understand their role in the development of the disease and patient survival over three years. Methods: The study included the assessment of TLR-2, TLR-3, TLR-4, TLR-7, TLR-8, and TLR-9 levels on peripheral blood lymphocytes in patients with newly diagnosed SCC and in the control group. The expression of TLRs was measured using flow cytometry, and the soluble forms of the tested TLRs were measured using enzyme-linked immunosorbent assays. All the analyses were conducted over a three-year period from the time patients were recruited to the study. The obtained test results were statistically analyzed. Results: Results showed statistically significant differences in TLR expression between the groups, with higher TLR levels correlating with an advanced stage of disease and poorer survival rates. This suggests that the deregulation of TLR levels may be involved in promoting tumor development and influencing its microenvironment. Conclusions: The research, conducted over three years, indicates the need for further research on the role of TLRs in SCC, including their potential use as therapeutic targets and biomarkers. This may help to increase the effectiveness of standard treatments and improve clinical outcomes in patients with SCC.

Design and Discovery of New Collagen V-Derived FGF2-Blocking Natural Peptides Inhibiting Lung Squamous Cell Carcinoma In Vitro and In Vivo

Aberrant FGF2/FGFR signaling is implicated in lung squamous cell carcinoma (LSCC), posing treatment challenges due to the lack of targeted therapeutic options. Designing drugs that block FGF2 signaling presents a promising strategy different from traditional kinase inhibitors. We previously reported a ColVα1-derived fragment, HEPV (127AA), that inhibits FGF2-induced angiogenesis. However, its large size may limit therapeutic application. This study combines rational peptide design, molecular dynamics simulations, knowledge-based prediction, and GUV and FRET assays to identify smaller peptides with FGF2-blocking properties. We synthesized two novel peptides, HBS-P1 (45AA) and HBS-P2 (66AA), that retained the heparin-binding site. Both peptides demonstrated anti-LSCC and antiangiogenesis properties in cell viability and microvessel network induction assays. In two LSCC subcutaneous models, HBS-P1, with its affinity for FGF2 and enhanced penetration ability, demonstrated substantial therapeutic potential without apparent toxicities. Our study provides the first evidence supporting the development of collagen V-derived natural peptides as FGF2-blocking agents for LSCC treatment.

p53 Genetics and Biology in Lung Carcinomas: Insights, Implications and Clinical Applications

The TP53 gene is renowned as a tumor suppressor, playing a pivotal role in overseeing the cell cycle, apoptosis, and maintaining genomic stability. Dysregulation of p53 often contributes to the initiation and progression of various cancers, including lung cancer (LC) subtypes. The review explores the intricate relationship between p53 and its role in the development and progression of LC. p53, a crucial tumor suppressor protein, exists in various isoforms, and understanding their distinct functions in LC is essential for advancing our knowledge of this deadly disease. This review aims to provide a comprehensive literature overview of p53, its relevance to LC, and potential clinical applications.

Smoking-induced CCNA2 expression promotes lung adenocarcinoma tumorigenesis by boosting AT2/AT2-like cell differentiation

Lung adenocarcinoma (LUAD), a type of non-small cell lung cancer (NSCLC), originates from not only bronchial epithelial cells but also alveolar type 2 (AT2) cells, which could differentiate into AT2-like cells. AT2-like cells function as cancer stem cells (CSCs) of LUAD tumorigenesis to give rise to adenocarcinoma. However, the mechanism underlying AT2 cell differentiation into AT2-like cells in LUAD remains unknown. We analyze genes differentially expressed and genes with significantly different survival curves in LUAD, and the combination of these two analyses yields 147 differential genes, in which 14 differentially expressed genes were enriched in cell cycle pathway. We next analyze the protein levels of these genes in LUAD and find that Cyclin-A2 (CCNA2) is closely associated with LUAD tumorigenesis. Unexpectedly, high CCNA2 expression in LUAD is restrictedly associated with smoking and independent of other driver mutations. Single-cell sequencing analyses reveal that CCNA2 is predominantly involved in AT2-like cell differentiation, while inhibition of CCNA2 significantly reverses smoking-induced AT2-like cell differentiation. Mechanistically, CCNA2 binding to CDK2 phosphorylates the AXIN1 complex, which in turn induces ubiquitination-dependent degradation of β-catenin and inhibits the WNT signaling pathway, thereby failing AT2 cell maintenance. These results uncover smoking-induced CCNA2 overexpression and subsequent WNT/β-catenin signaling inactivation as a hitherto uncharacterized mechanism controlling AT2 cell differentiation and LUAD tumorigenesis.

SMARCA4 mutation induces tumor cell-intrinsic defects in enhancer landscape and resistance to immunotherapy

Cancer genomic studies have identified frequent alterations in components of the SWI/SNF (SWItch/Sucrose Non- Fermenting) chromatin remodeling complex including SMARCA4 and ARID1A . Importantly, clinical reports indicate that SMARCA4 -mutant lung cancers respond poorly to immunotherapy and have dismal prognosis. However, the mechanistic basis of immunotherapy resistance is unknown. Here, we corroborated the clinical findings by using immune-humanized, syngeneic, and genetically engineered mouse models of lung cancer harboring SMARCA4 deficiency. Specifically, we show that SMARCA4 loss caused decreased response to anti-PD1 immunotherapy associated with significantly reduced infiltration of dendritic cells (DCs) and CD4+ T cells into the tumor microenvironment (TME). Mechanistically, we show that SMARCA4 loss in tumor cells led to profound downregulation of STING, IL1β and other components of the innate immune system as well as inflammatory cytokines that are required for efficient recruitment and activity of immune cells. We establish that this deregulation of gene expression is caused by cancer cell-intrinsic reprogramming of the enhancer landscape with marked loss of chromatin accessibility at enhancers of genes involved in innate immune response such as STING, IL1β, type I IFN and inflammatory cytokines. Interestingly, we observed that transcription factor NF-κB binding motif was highly enriched in enhancers that lose accessibility upon SMARCA4 deficiency. Finally, we confirmed that SMARCA4 and NF-κB co-occupy the same genomic loci on enhancers associated with STING and IL1β, indicating a functional interplay between SMARCA4 and NF-κB. Taken together, our findings provide the mechanistic basis for the poor response of SMARCA4 -mutant tumors to anti-PD1 immunotherapy and establish a functional link between SMARCA4 and NF-κB on innate immune and inflammatory gene expression regulation.

TNIK Inhibition Sensitizes TNIK-Overexpressing Lung Squamous Cell Carcinoma to Radiotherapy

Most patients with lung squamous cell carcinoma (LSCC) undergo chemotherapy, radiotherapy, and adjuvant immunotherapy for locally advanced disease. The efficacy of these treatments is still limited because of dose-limiting toxicity or locoregional recurrence. New combination approaches and targets such as actionable oncogenic drivers are needed to advance treatment options for patients with LSCC. Moreover, other options for chemotherapy-ineligible patients are limited. As such, there is a critical need for the development of selective and potent chemoradiosensitizers for locally advanced LSCC. In this study, we investigated inhibiting TRAF2- and NCK-interacting protein kinase (TNIK), which is amplified in 40% of patients with LSCC, as a strategy to sensitize LSCC tumors to chemotherapy and radiotherapy. Employing a range of human LSCC cell lines and the TNIK inhibitor NCB-0846, we investigated the potential of TNIK as a chemo- and radiosensitizing target with in vitro and in vivo preclinical models. The combination of NCB-0846 with cisplatin or etoposide was at best additive. Interestingly, pre-treating LSCC cells with NCB-0846 prior to ionizing radiation (IR) potentiated the cytotoxicity of IR in a TNIK-specific fashion. Characterization of the radiosensitization mechanism suggested that TNIK inhibition may impair the DNA damage response and promote mitotic catastrophe in irradiated cells. In a subcutaneous xenograft in vivo model, pretreatment with NCB-0846 significantly enhanced the efficacy of IR and caused elevated necrosis in TNIKhigh LK2 tumors but not TNIKlow KNS62 tumors. Overall, these results indicate that TNIK inhibition may be a promising strategy to increase the efficacy of radiotherapy in patients with LSCC with high TNIK expression.

Efficacy and safety of PD-1 inhibitors plus chemotherapy with or without endostatin for stage IV lung squamous cancer: a retrospective study

Backgroud

The study aimed to analyze the efficacy and safety of PD-1 inhibitors plus chemotherapy with or without endostatin for stage IV lung squamous cell carcinoma (LUSC).

Methods

A total of 219 patients with stage IV LUSC were included. 120 received PD-1 inhibitors plus chemotherapy with or without endostatin (IC ± A), of which 39 received endostatin (IC+A) and 81 did not receive endostatin (IC-A). 99 received chemotherapy with or without endostatin (C ± A). Endpoints included overall survival (OS), progression-free survival (PFS), adverse events (AEs), and immune-related adverse events (irAEs).

Results

The median PFS in the IC ± A group versus the C ± A group was 8 and 4 months (P < 0.001), and the median OS was 17 and 9 months (P < 0.001). There was no significant difference in any grade AEs between the IC ± A and C ± A groups (P > 0.05). The median PFS in the IC+A group versus the IC-A group was 11 and 7 months (P = 0.024), and the median OS was 34 and 15 months (P = 0.01). There was no significant difference between the IC+A group and the IC-A group for all grade AEs and irAEs (P > 0.05). The subgroup analysis showed that patients with LIPI = 0 had significant OS and PFS benefits in IC+A group, while for patients with LIPI = 1-2, there was no significant difference in OS and PFS benefits between the IC+A group and IC-A group.

Conclusions

PD-1 inhibitors plus chemotherapy with endostatin might be first-line treatment for patients with stage IV LUSC.

Machine learning-based identification of a cell death-related signature associated with prognosis and immune infiltration in glioma

Accumulating evidence suggests that a wide variety of cell deaths are deeply involved in cancer immunity. However, their roles in glioma have not been explored. We employed a logistic regression model with the shrinkage regularization operator (LASSO) Cox combined with seven machine learning algorithms to analyse the patterns of cell death (including cuproptosis, ferroptosis, pyroptosis, apoptosis and necrosis) in The Cancer Genome Atlas (TCGA) cohort. The performance of the nomogram was assessed through the use of receiver operating characteristic (ROC) curves and calibration curves. Cell-type identification was estimated by using the cell-type identification by estimating relative subsets of known RNA transcripts (CIBERSORT) and single sample gene set enrichment analysis methods. Hub genes associated with the prognostic model were screened through machine learning techniques. The expression pattern and clinical significance of MYD88 were investigated via immunohistochemistry (IHC). The cell death score represents an independent prognostic factor for poor outcomes in glioma patients and has a distinctly superior accuracy to that of 10 published signatures. The nomogram performed well in predicting outcomes according to time-dependent ROC and calibration plots. In addition, a high-risk score was significantly related to high expression of immune checkpoint molecules and dense infiltration of protumor cells, these findings were associated with a cell death-based prognostic model. Upregulated MYD88 expression was associated with malignant phenotypes and undesirable prognoses according to the IHC. Furthermore, high MYD88 expression was associated with poor clinical outcomes and was positively related to CD163, PD-L1 and vimentin expression in the in-horse cohort. The cell death score provides a precise stratification and immune status for glioma. MYD88 was found to be an outstanding representative that might play an important role in glioma.

Depletion of squalene epoxidase in synergy with glutathione peroxidase 4 inhibitor RSL3 overcomes oxidative stress resistance in lung squamous cell carcinoma

Background

Lung squamous cell carcinoma (LUSC) lacks effective targeted therapies and has a poor prognosis. Disruption of squalene epoxidase (SQLE) has been implicated in metabolic disorders and cancer. However, the role of SQLE as a monooxygenase involved in oxidative stress remains unclear.

Methods

We analyzed the expression and prognosis of lung adenocarcinoma (LUAD) and LUSC samples from GEO and TCGA databases. The proliferative activity of the tumors after intervention of SQLE was verified by cell and animal experiments. JC-1 assay, flow cytometry, and Western blot were used to show changes in apoptosis after intervention of SQLE. Flow cytometry and fluorescence assay of ROS levels were used to indicate oxidative stress status.

Results

We investigated the unique role of SQLE expression in the diagnosis and prognosis prediction of LUSC. Knockdown of SQLE or treatment with the SQLE inhibitor terbinafine can suppress the proliferation of LUSC cells by inducing apoptosis and reactive oxygen species accumulation. However, depletion of SQLE also results in the impairment of lipid peroxidation and ferroptosis resistance such as upregulation of glutathione peroxidase 4. Therefore, prevention of SQLE in synergy with glutathione peroxidase 4 inhibitor RSL3 effectively mitigates the proliferation and growth of LUSC.

Conclusion

Our study indicates that the low expression of SQLE employs adaptive survival through regulating the balance of apoptosis and ferroptosis resistance. In future, the combinational therapy of targeting SQLE and ferroptosis could be a promising approach in treating LUSC.

PLAU, transcriptionally negatively regulated by GATA6, promotes lung squamous carcinoma cell proliferation and migration

BACKGROUND

Lung squamous cell carcinoma (LUSC) is associated with high mortality and has limited therapeutic treatment options. Plasminogen activator urokinase (PLAU) plays important roles in tumor cell malignancy. However, the oncogenic role of PLAU in the progression of LUSC remains unknown. GATA-binding factor 6 (GATA6), a key regulator of lung development, inhibits LUSC cell proliferation and migration, but the underlying regulatory mechanism remains to be further explored. Moreover, the regulatory effect of GATA6 on PLAU expression has not been reported. The aim of this study was to identify the role of PLAU and the transcriptional inhibition mechanism of GATA6 on PLAU expression in LUSC.

METHODS

To identify the potential target genes regulated by GATA6, differentially expressed genes (DEGs) obtained from GEO datasets analysis and RNA-seq experiment were subjected to Venn analysis and correlation heatmap analysis. The transcriptional regulatory effects of GATA6 on PLAU expression were detected by real-time PCR, immunoblotting, and dual-luciferase reporter assays. The oncogenic effects of PLAU on LUSC cell proliferation and migration were evaluated by EdU incorporation, Matrigel 3D culture and Transwell assays. PLAU expression was detected in tissue microarray of LUSC via immunohistochemistry (IHC) assay. To determine prognostic factors for prognosis of LUSC patients, the clinicopathological characteristics and PLAU expression were subjected to univariate Cox regression analysis.

RESULTS

PLAU overexpression promoted LUSC cell proliferation and migration. PLAU is overexpressed in LUSC tissues compared with normal tissues. Consistently, high PLAU expression, which acts as an independent risk factor, is associated with poor prognosis of LUSC patients. Furthermore, the expression of PLAU is transcriptionally regulated by GATA6.

CONCLUSION

In this work, it was revealed that PLAU is a novel oncogene for LUSC and a new molecular regulatory mechanism of GATA6 in LUSC was unveiled. Targeting the GATA6/PLAU pathway might help in the development of novel therapeutic treatment strategies for LUSC.

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.

Different types of tumor microvessels in stage I-IIIA squamous cell lung cancer and their clinical significance

BACKGROUND

Lung cancer (LC) is the leading cause of morbidity and mortality among malignant neoplasms. Improving the diagnosis and treatment of LC remains an urgent task of modern oncology. Previously, we established that in gastric, breast and cervical cancer, tumor microvessels (MVs) differ in morphology and have different prognostic significance. The connection between different types of tumor MVs and the progression of LC is not well understood.

AIM

To evaluate the morphological features and clinical significance of tumor MVs in lung squamous cell carcinoma (LUSC).

METHODS

A single-center retrospective cohort study examined medical records and archival paraffin blocks of 62 and 180 patients with stage I-IIIA LUSC in the training and main cohorts, respectively. All patients underwent radical surgery (R0) at the Orenburg Regional Cancer Clinic from May/20/2009 to December/14/2021. Tumor sections were routinely processed, and routine Mayer's hematoxylin and eosin staining and immunohistochemical staining for cluster of differentiation 34 (CD34), podoplanin, Snail and hypoxia-inducible factor-1 alpha were performed. The morphological features of different types of tumor MVs, tumor parenchyma and stroma were studied according to clinicopathological characteristics and LUSC prognosis. Statistical analysis was performed using Statistica 10.0 software. Univariate and multivariate logistic regression analyses were performed to identify potential risk factors for LUSC metastasis to regional lymph nodes (RLNs) and disease recurrence. Receiver operating characteristic curves were constructed to discriminate between patients with and without metastases in RLNs and those with and without disease recurrence. The effectiveness of the predictive models was assessed by the area under the curve. Survival was analyzed using the Kaplan-Meier method. The log-rank test was used to compare survival curves between patient subgroups. A value of P < 0.05 was considered to indicate statistical significance.

RESULTS

Depending on the morphology, we classified tumor vessels into the following types: normal MVs, dilated capillaries (DCs), atypical DCs, DCs with weak expression of CD34, "contact-type" DCs, structures with partial endothelial linings, capillaries in the tumor solid component and lymphatic vessels in lymphoid and polymorphocellular infiltrates. We also evaluated the presence of loose, fine fibrous connective tissue (LFFCT) and retraction clefts in the tumor stroma, tumor spread into the alveolar air spaces (AASs) and fragmentation of the tumor solid component. According to multivariate analysis, the independent predictors of LUSC metastasis in RLNs were central tumor location (P < 0.00001), the presence of retraction clefts (P = 0.003), capillaries in the tumor solid component (P = 0.023) and fragmentation in the tumor solid component (P = 0.009), whereas the independent predictors of LUSC recurrence were tumor grade 3 (G3) (P = 0.001), stage N2 (P = 0.016), the presence of LFFCT in the tumor stroma (P < 0.00001), fragmentation of the tumor solid component (P = 0.0001), and the absence of tumor spread through the AASs (P = 0.0083).

CONCLUSION

The results obtained confirm the correctness of our previously proposed classification of different types of tumor vessels and may contribute to improving the diagnosis and treatment of LUSC.

RICTOR amplification is associated with Rictor membrane staining and does not correlate with PD-L1 expression in lung squamous cell carcinoma

RICTOR gene, which encodes the scaffold protein of mTORC2, can be amplified in various tumor types, including squamous cell carcinoma (SCC) of the lung. RICTOR amplification can lead to hyperactivation of mTORC2 and may serve as a targetable genetic alteration, including in lung SCC patients with no PD-L1 expression who are not expected to benefit from immune checkpoint inhibitor therapy. This study aimed to compare RICTOR amplification detected by fluorescence in situ hybridization (FISH) with Rictor and PD-L1 protein expression detected by immunohistochemistry (IHC) in SCC of the lung. The study was complemented by analysis of the publicly available Lung Squamous Cell Carcinoma (TCGA, Firehose legacy) dataset. RICTOR amplification was observed in 20% of our cases and 16% of the lung SCC cases of the TCGA dataset. Rictor and PD-L1 expression was seen in 74% and 44% of the cases, respectively. Rictor IHC showed two staining patterns: membrane staining (16% of the cases) and cytoplasmic staining (58% of the cases). Rictor membrane staining predicted RICTOR amplification as detected by FISH with high specificity (95%) and sensitivity (70%). We did not find any correlation between RICTOR amplification and PD-L1 expression; RICTOR amplification was detected in 18% and 26% of PD-L1 positive and negative cases, respectively. The TCGA dataset analysis showed similar results; RICTOR copy number correlated with Rictor mRNA and protein expression but showed no association with PD-L1 mRNA and protein expression. In conclusion, the correlation between RICTOR amplification and Rictor membrane staining suggests that the latter can potentially be used as a surrogate marker to identify lung SCC cases with RICTOR amplification. Since a significant proportion of PD-L1 negative SCC cases harbor RICTOR amplification, analyzing PD-L1 negative tumors by RICTOR FISH or Rictor IHC can help select patients who may benefit from mTORC2 inhibitor therapy.

Construction of a prognostic model with CAFs for predicting the prognosis and immunotherapeutic response of lung squamous cell carcinoma

Lung squamous cell carcinoma (LUSC) is one of the subtypes of lung cancer (LC) that contributes to approximately 25%-30% of its prevalence. Cancer-associated fibroblasts (CAFs) are key cellular components of the TME, and the large number of CAFs in tumour tissues creates a favourable environment for tumour development. However, the function of CAFs in the LUSC is complex and uncertain. First, we processed the scRNA-seq data and classified distinct types of CAFs. We also identified prognostic CAFRGs using univariate Cox analysis and conducted survival analysis. Additionally, we assessed immune cell infiltration in CAF clusters using ssGSEA. We developed a model with a significant prognostic correlation and verified the prognostic model. Furthermore, we explored the immune landscape of LUSC and further investigated the correlation between malignant features and LUSC. We identified CAFs and classified them into three categories: iCAFs, mCAFs and apCAFs. The survival analysis showed a significant correlation between apCAFs and iCAFs and LUSC patient prognosis. Kaplan-Meier analysis showed that patients in CAF cluster C showed a better survival probability compared to clusters A and B. In addition, we identified nine significant prognostic CAFRGs (CLDN1, TMX4, ALPL, PTX3, BHLHE40, TNFRSF12A, VKORC1, CST3 and ADD3) and subsequently employed multivariate Cox analysis to develop a signature and validate the model. Lastly, the correlation between CAFRG and malignant features indicates the potential role of CAFRG in promoting tumour angiogenesis, EMT and cell cycle alterations. We constructed a CAF prognostic signature for identifying potential prognostic CAFRGs and predicting the prognosis and immunotherapeutic response for LUSC. Our study may provide a more accurate prognostic assessment and immunotherapy targeting strategies for LUSC.

Expanding Broad Molecular Reflex Testing in Non-Small Cell Lung Cancer to Squamous Histology

Due to the success story of biomarker-driven targeted therapy, most NSCLC guidelines agree that molecular reflex testing should be performed in all cases with non-squamous cell carcinoma (non-SCC). In contrast, testing recommendations for squamous cell carcinoma (SCC) vary considerably, specifically concerning the exclusion of patients of certain age or smoking status from molecular testing strategies. We performed a retrospective single-center study examining the value of molecular reflex testing in an unselected cohort of 316 consecutive lung SCC cases, tested by DNA- and RNA-based next-generation sequencing (NGS) at our academic institution between 2019 and 2023. Clinicopathological data from these cases were obtained from electronic medical records and correlated with sequencing results. In 21/316 (6.6%) cases, we detected an already established molecular target for an approved drug. Among these were seven cases with an EGFR mutation, seven with a KRAS G12C mutation, four with an ALK fusion, two with an EGFR fusion and one with a METex14 skipping event. All patients harboring a targetable alteration were >50 years of age and most of them had >15 pack-years, questioning restrictive molecular testing strategies. Based on our real-world data, we propose a reflex testing workflow using DNA- and RNA-based NGS that includes all newly diagnosed NSCLC cases, irrespective of histology, but also irrespective of age or smoking status.

MiR-320a upregulation contributes to the effectiveness of pemetrexed by inhibiting the growth and invasion of human lung cancer cell line (Calu-6)

BACKGROUND

Lung cancer is a common and deadly disease. Chemotherapy is the most common treatment, which inhibits cancer cell growth. Pemetrexed (PMX) is often used with other drugs. Environmental stress can affect regulatory non-coding RNAs such as MicroRNAs that modify gene expression. This study investigates the effect of PMX on the hsa-miR-320a-3p expression in the Calu-6 lung cancer cell line.

METHODS AND RESULT

Calu-6 cells were cultured in an incubator with 37 °C, 5% CO2, and 98% humidity. The MTT test was performed to determine the concentration of PMX required to inhibit 50% of cell growth. To examine growth inhibition and apoptosis, release of lactate dehydrogenase (LDH), cell assays and caspase 3 and 7 enzyme activity were used. Finally, molecular studies were conducted to compare the expression of hsa-miR-320a-3p and genes including VDAC1, DHFR, STAT3, BAX and BCL2 before and after therapy.

RESULTS

According to a study, it has been observed that PMX therapy significantly increases LDH release after 24 h. The study found that PMX's IC50 on Calu-6 is 8.870 µM. In addition, the treated sample showed higher expression of hsa-miR-320a-3p and BAX, while the expression of VDAC1, STAT3, DHFR and BCL2 decreased compared to the control sample.

CONCLUSION

According to the findings of the current research, hsa-miR-320a-3p seems to have the potential to play an important role in the development of novel approaches to the treatment of lung cancer.

Re-inventing a better wheel? Serplulimab for squamous cell lung cancer

Immune checkpoint inhibitors have reshaped the treatment landscape of non-small cell lung cancer (NSCLC). However, chemoimmunotherapy trials dedicated to squamous NSCLC are limited. In this issue of Cancer Cell, Zhou et al. demonstrate serplulimab plus chemotherapy as an effective first-line regimen to treat patients with advanced squamous NSCLC.

Characterization and verification of CD81 as a potential target in lung squamous cell carcinoma

CD81 is a cell surface transmembrane protein of the tetraspanin family, which critically regulates signal transduction and immune response. Growing evidence has shown that CD81 plays important roles in tumorigenesis and influences immunotherapy response. Here, combining bio-informatics and functional analysis, we find that CD81 is a risk factor in lung squamous cell carcinoma (LUSC), whereas a protective factor in lung adenocarcinoma. In LUSC with high expression of CD81, the autophagy and JAK-STAT signaling pathway are activated. Meanwhile, the expression level of CD81 is negatively correlated with tumor mutational load (TMB), microsatellite instability (MSI), and neoantigen (NEO). Furthermore, patients with LUSC and high expression of CD81 do not respond to immunotherapy drugs, but can respond to chemotherapy drugs. Importantly, depletion of CD81 suppresses the proliferation of LUSC cell, and enhances the sensitivity to cisplatin. Our findings suggest that CD81 represents a potential target for cisplatin-based chemotherapy in patients with LUSC.

Population-based high-dimensional analyses identify multiple intrinsic characters for cancer vaccines against lung squamous cell carcinoma

In lung squamous cell carcinoma (LUSC), current cancer vaccines show promising effects, despite a lack of benefit for a large number of patients. We first identified the tumor antigens into shared and private antigens, and determined the population by clustering analysis in public datasets. For vaccine development, The Cancer Genome Atlas (TCGA) and Clinical Proteomic Tumor Analysis Consortium (CPTAC) were collected. WGCNA method was furthermore applied to construct a consensus gene co-expression network based on TCGA and CPTAC datasets. The main analyses in bulk sequencing included survival, clinical features, tumor microenvironment (TME), and pathways enrichment. In addition, single-cell RNA (scRNA) analysis of cancer epithelium dissected consensus subtype. We identified the ideal population for cancer vaccines, and candidate neoantigens including AOC1, COL5A2, LGI2, and POSTN. According to subtype analysis, Lung squamous 1 (LSQ1) type exhibited a higher tumor mutational load (TMB) and copy number but no immune infiltration, whereas lung squamous 2 (LSQ2) tumors had a higher global methylation level and more fibroblasts but had less stemness. Meanwhile, trajectory analysis further revealed that the evolution of TME influenced prognosis. We emphasized specific pathways or targets with the potential for combination immunotherapy by consensus network and single-cell RNA analyses. Anti-androgen therapy has been validated in vitro experiments of LUSC as proof of concept. In conclusion, LSQ1 was linked to immune exclusion and might be utilized for vaccination, while LSQ2 was linked to immune dysfunction and could be used for programmed cell death protein 1 (PD1) blocking therapy.

Pulmonary squamous cell carcinoma and lymphoepithelial carcinoma - morphology, molecular characteristics and differential diagnosis

Squamous cell carcinoma (SCC) comprises one of the major groups of non-small-cell carcinoma of the lung, and is subtyped into keratinising, non-keratinising and basaloid SCC. SCC can readily be diagnosed using histomorphology alone in keratinising SCC. Confirmatory immunohistochemical analyses should always be applied in non-keratinising and basaloid tumours to exclude differential diagnoses, most prominently adenocarcinoma and high-grade neuroendocrine carcinoma, which may have important therapeutic consequences. According to the World Health Organisation (WHO) classification 2015, the diagnosis of SCC can be rendered in resections of morphologically ambiguous tumours with squamous immunophenotype. In biopsies and cytology preparations in the same setting the current guidelines propose a diagnosis of 'non-small-cell carcinoma, favour SCC' in TTF1-negative and p40-positive tumours to acknowledge a possible sampling bias and restrict extended immunohistochemical evaluation in order to preserve tissue for molecular testing. Most SCC feature a molecular 'tobacco-smoke signature' with enrichment in GG > TT mutations, in line with the strong epidemiological association of SCC with smoking. Targetable mutations are extremely rare but they do occur, in particular in younger and non- or light-smoking patients, warranting molecular investigations. Lymphoepithelial carcinoma (LEC) is a poorly differentiated SCC with a syncytial growth pattern and a usually prominent lymphoplasmacytic infiltrate and frequent Epstein-Barr virus (EBV) association. In this review, we describe the morphological and molecular characteristics of SCC and LEC and discuss the most pertinent differential diagnoses.

USP13 drives lung squamous cell carcinoma by switching lung club cell lineage plasticity

Lung squamous cell carcinoma (LUSC) is associated with high mortality and limited targeted therapies. USP13 is one of the most amplified genes in LUSC, yet its role in lung cancer is largely unknown. Here, we established a novel mouse model of LUSC by overexpressing USP13 on KrasG12D/+; Trp53flox/flox background (KPU). KPU-driven lung squamous tumors faithfully recapitulate key pathohistological, molecular features, and cellular pathways of human LUSC. We found that USP13 altered lineage-determining factors such as NKX2-1 and SOX2 in club cells of the airway and reinforced the fate of club cells to squamous carcinoma development. We showed a strong molecular association between USP13 and c-MYC, leading to the upregulation of squamous programs in murine and human lung cancer cells. Collectively, our data demonstrate that USP13 is a molecular driver of lineage plasticity in club cells and provide mechanistic insight that may have potential implications for the treatment of LUSC.

Microbiota modulate lung squamous cell carcinoma lymph node metastasis through microbiota-geneset correlation network

BACKGROUND

The tumor-resident microbiota in lung squamous cell carcinoma (LUSC) has been reported to be associated with the initiation and progression of cancer. And the gut microbiome can modulate the efficacy of immunotherapies. However, it remains to be understood whether the tumor-resident microbiome promotes lymph node (LN) metastasis, which is important for clinical decision-making and prediction of a patient's prognosis. To investigate the potential role of tumor-resident microbiota in LN metastasis, we worked on the microbiota-geneset interaction profiles to characterize the molecular pathogenesis.

METHODS

RNA sequencing data and their matched clinical and genomic information were obtained from The Cancer Genome Atlas database. The matched microorganism quantification data were accessed via the cBioPortal database. The mutational signature analysis, transcriptome analysis, gene set enrichment analysis, immune infiltration, and microbiota-geneset network analysis were performed.

RESULTS

In this paper, we identified the tumor microbiota composition and microbial biomarkers in patients with and without LN metastases. In addition, significantly upregulated gene sets characterize the transcript profiles of patients with LN metastases, for example, Myc Targets, E2F Targets, G2M Checkpoint, Mitotic Spindle, DNA Repair, and Oxidative Phosphorylation. Finally, we found that Proteus and Bacteroides were strongly correlated with gene sets related to tumor development and energy metabolism in the networks of patients with LN metastases.

CONCLUSIONS

We found the associations between intratumor microbiota and transcripts. Our results shed light on the correlation network of Proteus and Bacteroides, which may serve as a novel strategy for modulating LN metastasis.

Online decision tools for personalized survival prediction and treatment optimization in elderly patients with lung squamous cell carcinoma: a retrospective cohort study

BACKGROUND

Despite major advances in cancer therapeutics, the therapeutic options of Lung Squamous Cell Carcinoma (LSCC)-specific remain limited. Furthermore, the current staging system is imperfect for defining a prognosis and guiding treatment due to its simplicity and heterogeneity. We sought to develop prognostic decision tools for individualized survival prediction and treatment optimization in elderly patients with LSCC.

METHODS

Clinical data of 4564 patients (stageIB-IIIB) diagnosed from 2010 to 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database for prognostic nomograms development. The proposed models were externally validated using a separate group consisting of 1299 patients (stage IB-IIIB) diagnosed from 2012-2015 in China. The prognostic performance was measured using the concordance index (C-index), calibration curves, the average time-dependent area under the receiver operator characteristic curves (AUC), and decision curve analysis.

RESULTS

Eleven candidate prognostic variables were identified by the univariable and multivariable Cox regression analysis. The calibration curves showed satisfactory agreement between the actual and nomogram-estimated Lung Cancer-Specific Survival (LCSS) rates. By calculating the c-indices and average AUC, our nomograms presented a higher prognostic accuracy than the current staging system. Clinical usefulness was revealed by the decision curve analysis. User-friendly online decision tools integrating proposed nomograms were created to estimate survival for patients with different treatment regimens.

CONCLUSIONS

The decision tools for individualized survival prediction and treatment optimization might facilitate clinicians with decision-making, medical teaching, and experimental design. Online tools are expected to be integrated into clinical practice by using the freely available website ( https://loyal-brand-611803.framer.app/ ).

Successful treatment of immune-related lichenoid dermatitis by Weiling decoction in a patient with non-small cell lung cancer: A case report and review of literature

BACKGROUND

Immune checkpoint inhibitors (ICIs) have emerged as a revolutionary therapy in advanced squamous non-small cell lung cancer (sqNSCLC) and ushered a new era of immunotherapy. Despite of remarkable outcomes, a wide spectrum of immune-related adverse events (irAEs) was reported, among which cutaneous reactions were the most common. Cutaneous irAEs were mainly managed by glucocorticoids, whereas prolonged use of glucocorticoids may cuase kinds of side effects, especially in elderly paitients, and diminish the anti-tumor efficacy of ICIs, thus finding a safe and effective alternative approach to managing cutaneous irAEs is imperative.

CASE SUMMARY

A 71-year-old man who was diagnosed with advanced sqNSCLC suffered from sporadic maculopapulars one week later after the fifth cycle of sintilimab treatment, and the skin lesions had been deteriorating rapidly. Skin biopsy revealed epidermal parakeratosis with a dense band-like lymphocytic infiltrate and acanthosis, indicating a diagnosis of immune-induced lichenoid dermatitis. Oral administration of traditional Chinese herbal formula modified Weiling decoction significantly alleviated the symptoms of the patient. The dosage of Weiling decoction were maintained for about three months without recurrence of cutaneous adverse reactions and any other side effects. The patient refused to receive further anti-tumor medication and stayed alive without disease progression at follow up.

CONCLUSION

We present modified Weiling decoction successfully ameliorates immune-induced lichenoid dermatitis in a patient with sqNSCLC for the first time. This report indicates that Weiling decoction may be an effective and safe complementary or alternative approach for the treatment of cutaneous irAEs. Further investigation of the underling mechanism is required in the future.

Characterization of platelet-related genes and constructing signature combined with immune-related genes for predicting outcomes and immunotherapy response in lung squamous cell carcinoma

Lung squamous cell carcinoma (LUSC) is a highly malignant subtype of non-small cell lung cancer with poor prognosis. Platelets are known to play a critical role in cancer development and progression, and recent studies suggest that they can also regulate immune response in tumors. However, the relationship between platelet-related genes (PRGs) and LUSC prognosis and tumor microenvironments remains unclear. In this study, we used multiple bioinformatics algorithms to identify 25 dysregulated PRGs that were significantly associated with LUSC prognosis. We found that PRGs were involved in multiple biological processes, particularly in the tumor microenvironment, and that platelet-related scores (PRS) were a risk factor. Additionally, we established a 6-gene prognostic signature combining PRGs and immune-related genes that accurately predicted outcomes and immunotherapy efficacy in LUSC patients. Our study provides a comprehensive analysis of the biological functions and potential therapeutic targets of PRGs in LUSC, which may inform the development of new treatments for this disease.

Characterization of stemness features and construction of a stemness subtype classifier to predict survival and treatment responses in lung squamous cell carcinoma

BACKGROUND

Cancer stemness has been proven to affect tumorigenesis, metastasis, and drug resistance in various cancers, including lung squamous cell carcinoma (LUSC). We intended to develop a clinically applicable stemness subtype classifier that could assist physicians in predicting patient prognosis and treatment response.

METHODS

This study collected RNA-seq data from TCGA and GEO databases to calculate transcriptional stemness indices (mRNAsi) using the one-class logistic regression machine learning algorithm. Unsupervised consensus clustering was conducted to identify a stemness-based classification. Immune infiltration analysis (ESTIMATE and ssGSEA algorithms) methods were used to investigate the immune infiltration status of different subtypes. Tumor Immune Dysfunction and Exclusion (TIDE) and Immunophenotype Score (IPS) were used to evaluate the immunotherapy response. The pRRophetic algorithm was used to estimate the efficiency of chemotherapeutic and targeted agents. Two machine learning algorithms (LASSO and RF) and multivariate logistic regression analysis were performed to construct a novel stemness-related classifier.

RESULTS

We observed that patients in the high-mRNAsi group had a better prognosis than those in the low-mRNAsi group. Next, we identified 190 stemness-related differentially expressed genes (DEGs) that could categorize LUSC patients into two stemness subtypes. Patients in the stemness subtype B group with higher mRNAsi scores exhibited better overall survival (OS) than those in the stemness subtype A group. Immunotherapy prediction demonstrated that stemness subtype A has a better response to immune checkpoint inhibitors (ICIs). Furthermore, the drug response prediction indicated that stemness subtype A had a better response to chemotherapy but was more resistant to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). Finally, we constructed a nine-gene-based classifier to predict patients' stemness subtype and validated it in independent GEO validation sets. The expression levels of these genes were also validated in clinical tumor specimens.

CONCLUSION

The stemness-related classifier could serve as a potential prognostic and treatment predictor and assist physicians in selecting effective treatment strategies for patients with LUSC in clinical practice.

Metabolomic differentiation of benign vs malignant pulmonary nodules with high specificity via high-resolution mass spectrometry analysis of patient sera

Differential diagnosis of pulmonary nodules detected by computed tomography (CT) remains a challenge in clinical practice. Here, we characterize the global metabolomes of 480 serum samples including healthy controls, benign pulmonary nodules, and stage I lung adenocarcinoma. The adenocarcinoma demonstrates a distinct metabolomic signature, whereas benign nodules and healthy controls share major similarities in metabolomic profiles. A panel of 27 metabolites is identified in the discovery cohort (n = 306) to distinguish between benign and malignant nodules. The discriminant model achieves an AUC of 0.915 and 0.945 in the internal validation (n = 104) and external validation cohort (n = 111), respectively. Pathway analysis reveals elevation in glycolytic metabolites associated with decreased tryptophan in serum of lung adenocarcinoma vs benign nodules and healthy controls, and demonstrates that uptake of tryptophan promotes glycolysis in lung cancer cells. Our study highlights the value of the serum metabolite biomarkers in risk assessment of pulmonary nodules detected by CT screening.

KMT2D deficiency drives lung squamous cell carcinoma and hypersensitivity to RTK-RAS inhibition

Lung squamous cell carcinoma (LUSC) represents a major subtype of lung cancer with limited treatment options. KMT2D is one of the most frequently mutated genes in LUSC (>20%), and yet its role in LUSC oncogenesis remains unknown. Here, we identify KMT2D as a key regulator of LUSC tumorigenesis wherein Kmt2d deletion transforms lung basal cell organoids to LUSC. Kmt2d loss increases activation of receptor tyrosine kinases (RTKs), EGFR and ERBB2, partly through reprogramming the chromatin landscape to repress the expression of protein tyrosine phosphatases. These events provoke a robust elevation in the oncogenic RTK-RAS signaling. Combining SHP2 inhibitor SHP099 and pan-ERBB inhibitor afatinib inhibits lung tumor growth in Kmt2d-deficient LUSC murine models and in patient-derived xenografts (PDXs) harboring KMT2D mutations. Our study identifies KMT2D as a pivotal epigenetic modulator for LUSC oncogenesis and suggests that KMT2D loss renders LUSC therapeutically vulnerable to RTK-RAS inhibition.