Identification of diagnostic biomarkers and immune cell infiltration in tongue squamous cell carcinoma using bioinformatic approaches.

OBJECTIVE: In this study, we employed a bioinformatics approach to identify diagnostic biomarkers for tongue squamous cell carcinoma (TSCC) and investigate the infiltration of immune cells in TSCC, as well as the relationship between biomarkers and immune cells. METHODS: We obtained the TSCC expression dataset from a database and conducted differential gene expression analysis between TSCC and adjacent normal tissues using R software. Enrichment analysis of the differentially expressed genes (DEGs) was performed using the DAVID website. Protein interaction networks for the DEGs were constructed, and hub genes were identified using tools such as STRING and Cytoscape. Survival analysis was conducted to identify diagnostic biomarkers and the infiltration of immune cells in TSCC was analyzed using the inverse convolution algorithm with Cibersort software. Finally, the expression of the discovered molecules was verified through clinical pathological sections. RESULTS: We identified 24 DEGs in TSCC, primarily associated with signal transduction, substance metabolism, innate immune response, and other related signaling pathways. Among the 24 hub genes screened through the construction of a protein-protein interaction (PPI) network, seven (MMP13, POSTN, MMP9, MMP10, MMP3, SPP1, MMP1) exhibited prognostic value. Survival analysis indicated that SPP1 demonstrated diagnostic potential. The expression level of the SPP1 gene showed a correlation with TSCC as well as several immune cell types, including macrophage M0, M1, M2, CD8+ T cell, activated NK cell, and monocyte (p < 0.05). Histological results confirmed higher expression of SPP1 in TSCC tissues compared to adjacent non-cancerous tissues, particularly in CD68-expressing macrophages. CONCLUSION: Our findings suggest that SPP1 serves as a diagnostic biomarker for TSCC and is involved in immune cell infiltration within TSCC tissues. The correlation between SPP1 and macrophages may offer new insights for targeted therapeutic research on TSCC.

Chromatin remodeling-driven autophagy activation induces cisplatin resistance in oral squamous cell carcinoma.

It is still challenging to predict the efficacy of cisplatin-based therapy, particularly in relation to the activation of macroautophagy/autophagy in oral squamous cell carcinoma (OSCC). We studied the effect of selected chromatin remodeling genes on the cisplatin resistance and their interplay with autophagy in 3-dimensional tumor model and xenografts. We analyzed gene expression patterns in the cisplatin-sensitive UMSCC1, and a paired cisplatin-resistant UM-Cis cells. Many histone protein gene clusters involved in nucleosome assembly showed significant difference of expression. Gain- and loss-of-function analyses revealed an inverse correlation between cisplatin resistance and HIST1H3D expression, while a positive correlation was observed with HIST3H2A or HIST3H2B expression. In UM-Cis, HIST3H2A- and HIST3H2B-mediated chromatin remodeling upregulates autophagy status, which results in cisplatin resistance. Additionally, knockdown of HIST3H2A or HIST3H2B downregulated autophagy-activating genes via chromatin compaction of their promoter regions. MiTF, one of the key autophagy regulators upregulated in UM-Cis, negatively regulated transcription of HIST1H3D, suggesting an interplay between chromatin remodeling-dependent cisplatin resistance and autophagy. On comparing the staining intensity between cisplatin-sensitive and -insensitive tissues from OSCC patients, protein expression pattern of the selected histone protein genes were matched with the in vitro data. By examining the relationship between autophagy and chromatin remodeling genes, we identified a set of candidate genes with potential use as markers predicting chemoresistance in OSCC biopsy samples.

The spatial distribution of intermediate fibroblasts and myeloid-derived cells dictate lymph node metastasis dynamics in oral cancer.

BACKGROUND: Oral cancer poses a significant health challenge due to limited treatment protocols and therapeutic targets. We aimed to investigate the invasive margins of gingivo-buccal oral squamous cell carcinoma (GB-OSCC) tumors in terms of the localization of genes and cell types within the margins at various distances that could lead to nodal metastasis. METHODS: We collected tumor tissues from 23 resected GB-OSCC samples for gene expression profiling using digital spatial transcriptomics. We monitored differential gene expression at varying distances between the tumor and its microenvironvent (TME), and performed a deconvulation study and immunohistochemistry to identify the cells and genes regulating the TME. RESULTS: We found that the tumor-stromal interface (a distance up to 200 µm between tumor and immune cells) is the most active region for disease progression in GB-OSCC. The most differentially expressed apex genes, such as FN1 and COL5A1, were located at the stromal ends of the margins, and together with enrichment of the extracellular matrix (ECM) and an immune-suppressed microenvironment, were associated with lymph node metastasis. Intermediate fibroblasts, myocytes, and neutrophils were enriched at the tumor ends, while cancer-associated fibroblasts (CAFs) were enriched at the stromal ends. The intermediate fibroblasts transformed into CAFs and relocated to the adjacent stromal ends where they participated in FN1-mediated ECM modulation. CONCLUSION: We have generated a functional organization of the tumor-stromal interface in GB-OSCC and identified spatially located genes that contribute to nodal metastasis and disease progression. Our dataset might now be mined to discover suitable molecular targets in oral cancer.

XPO1 serves as a prognostic marker involving AKT/MAPK/TGFBR1 pathway in OSCC.

BACKGROUND: Exportin 1 (XPO1) is a nuclear export protein that facilitates the transportation of various substances. XPO1 promotes tumor development as a poor prognostic factor in a variety of tumors and is a therapeutic target for screening inhibitors. However, the role of XPO1 in oral squamous cell carcinoma (OSCC) has yet to be determined. METHODS: The expression patterns of XPO1 mRNA in OSCC were investigated using bioinformatics tools, and the expression levels of XPO1 protein in OSCC specimens were confirmed by immunohistochemical assays. Survival analysis was conducted to evaluate the impact of XPO1 on prognosis. GO and KEGG enrichment analyses were utilized to uncover the signaling pathways mediated by XPO1. Additionally, we examined the association between XPO1 and AKT/MAPK/TGFBR1 and immune infiltration. RESULTS: XPO1 mRNA and protein expression levels were significantly enhanced in OSCC and associated with OSCC severity. Enhanced XPO1 expression was indicative of poor survival. Functional analysis showed that XPO1 mediated pathways associated with cell cycle and DNA replication and reduced immune infiltration in OSCC. Additionally, XPO1 mRNA and protein expression levels had significant positive relationships with AKT/MAPK/TGFBR1. CONCLUSIONS: XPO1, as a marker of poor prognosis in OSCC, can promote OSCC through AKT/MAPK/TGFBR1.

Exploring the prognostic landscape of oral squamous cell carcinoma through mitochondrial damage-related genes.

Oral squamous cell carcinoma (OSCC), the most prevalent form of oral cancer, poses significant challenges to the medical community due to its high recurrence rate and low survival rate. Mitochondrial Damage-Related Genes (MDGs) have been closely associated with the occurrence, metastasis, and progression of OSCC. Consequently, we constructed a prognostic model for OSCC based on MDGs and identified potential mitochondrial damage-related biomarkers. Gene expression profiles and relevant clinical information were obtained from The Cancer Genome Atlas (TCGA) database. Differential analysis was conducted to identify MDGs associated with OSCC. COX analysis was employed to screen seven prognosis-related MDGs and build a prognostic prediction model for OSCC. Cases were categorized into low-risk or high-risk groups based on the optimal risk score threshold. Kaplan-Meier (KM) analysis revealed significant survival differences (P < 0.05). Additionally, the area under the ROC curve (AUC) for patient survival at 1 year, 3 years, and 5 years were 0.687, 0.704, and 0.70, respectively, indicating a high long-term predictive accuracy of the prognostic model. To enhance predictive accuracy, age, gender, risk score, and TN staging were incorporated into a nomogram and verified using calibration curves. Risk scoring based on MDGs was identified as a potential independent prognostic biomarker. Furthermore, BID and SLC25A20 were identified as two potential independent mitochondrial damage-related prognostic biomarkers, offering new therapeutic targets for OSCC.

Pituitary tumor­transforming gene 1 regulates the senescence and apoptosis of oral squamous cell carcinoma in a p21­dependent DNA damage response manner.

Pituitary tumor­transforming gene 1 (PTTG1), also known as securin, is a proto­oncogene involved in the development of various cancers by promoting cell proliferation and mobility. However, its underlying biological mechanisms in oral squamous cell carcinoma (OSCC) progression remain unclear. in the present study, it was sought to elucidate the role of PTTG1 as an oncogene in OSCC progression and was attempted to unravel the underlying mechanism and impact of PTTG1 expression on cell cycle, cell death, and cellular senescence. The effect of double strand break on PTTG1 expression was investigated in OSCC growth. To identify the role of PTTG1 in OSCC growth, the cell viability and senescence was analyzed by EdU and senescence­associated beta­galactosidase (SA­ß­gal) assay, respectively. To verify the DNA damage­induced senescence of PTTG1, the chromosomal damage in OSCC was analyzed in vitro. Finally, the effect of PTTG1 on tumor growth and gene expression related to cell viability and DNA damaged­induced senescence was investigated in vivo. PTTG1 expression was compared between OSCC and healthy patient samples (n=32) using reverse transcription­quantitative PCR and immunohistochemistry; and it was found that PTTG1 expression was upregulated in OSCC. Small interfering RNA­mediated knockdown of PTTG1 in two OSCC cell lines revealed that PTTG1 downregulation significantly inhibited cell proliferation and arrested the cell cycle pathway as evidenced by changes in checkpoint genes (such as cyclin D1, E and B1). PTTG1 knockdown also increased apoptosis, as evidenced by the upregulation of apoptotic genes [such as cleaved (c­) Caspase­7 and c­poly (ADP­ribose) polymerase]. Moreover, PTTG1 downregulation promoted cellular senescence, as shown by western blotting and SA­ß­gal staining. Finally, senescence­induced DNA damage was observed in OSCC cells, which accelerates genomic instability, through chromosomal damage analysis. Taken together, the present findings suggested that PTTG1 acts as a proto­oncogene; regulates cell proliferation, cell cycle, cellular senescence and DNA damage in OSCC; and may serve as a novel diagnostic biomarker and potential therapeutic target for OSCC.

Noncanonical formation of SNX5 gene-derived circular RNA regulates cancer growth.

Oral squamous cell carcinoma (OSCC) is a prevalent cancer worldwide, exhibiting unique regional prevalence. Despite advancements in diagnostics and therapy, the 5-year survival rate for patients has seen limited improvement. A deeper understanding of OSCC pathogenesis, especially its molecular underpinnings, is essential for improving detection, prevention, and treatment. In this context, noncoding RNAs, such as circular RNAs (circRNAs), have gained recognition as crucial regulators and potential biomarkers in OSCC progression. Our study highlights the discovery of previously uncharacterized circRNAs, including a SNX5 gene-derived circRNA, circSNX5, through deep sequencing of OSCC patient tissue transcriptomes. We established circSNX5's tumor-specific expression and its strong correlation with patient survival using structure-specific and quantitative PCR analyses. In vitro and in vivo experiments underscored circSNX5 RNA's regulatory role in cancer growth and metastasis. Further, our omics profiling and functional assays revealed that ADAM10 is a critical effector in circSNX5-mediated cancer progression, with circSNX5 maintaining ADAM10 expression by sponging miR-323. This novel circRNA-miRNA-mRNA regulatory axis significantly contributes to oral cancer progression and malignancy. Moreover, we discovered that circSNX5 RNA is produced via noncanonical sequential back-splicing of pre-mRNA, a process negatively regulated by the RNA-binding protein STAU1. This finding adds a new dimension to our understanding of exonic circRNA biogenesis in the eukaryotic transcriptome. Collectively, our findings offer a detailed mechanistic dissection and functional interpretation of a novel circRNA, shedding light on the role of the noncoding transcriptome in cancer biology and potentially paving the way for innovative therapeutic strategies.

Distinctive field effects of smoking and lung cancer case-control status on bronchial basal cell growth and signaling.

RATIONAL: Basal cells (BCs) are bronchial progenitor/stem cells that can regenerate injured airway that, in smokers, may undergo malignant transformation. As a model for early stages of lung carcinogenesis, we set out to characterize cytologically normal BC outgrowths from never-smokers and ever-smokers without cancers (controls), as well as from the normal epithelial "field" of ever-smokers with anatomically remote cancers, including lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC) (cases). METHODS: Primary BCs were cultured and expanded from endobronchial brushings taken remote from the site of clinical or visible lesions/tumors. Donor subgroups were tested for growth, morphology, and underlying molecular features by qRT-PCR, RNAseq, flow cytometry, immunofluorescence, and immunoblot. RESULTS: (a) the BC population includes epithelial cell adhesion molecule (EpCAM) positive and negative cell subsets; (b) smoking reduced overall BC proliferation corresponding with a 2.6-fold reduction in the EpCAMpos/ITGA6 pos/CD24pos stem cell fraction; (c) LUSC donor cells demonstrated up to 2.8-fold increase in dysmorphic BCs; and (d) cells procured from LUAD patients displayed increased proliferation and S-phase cell cycle fractions. These differences corresponded with: (i) disparate NOTCH1/NOTCH2 transcript expression and altered expression of potential downstream (ii) E-cadherin (CDH1), tumor protein-63 (TP63), secretoglobin family 1a member 1 (SCGB1A1), and Hairy/enhancer-of-split related with YRPW motif 1 (HEY1); and (iii) reduced EPCAM and increased NK2 homeobox-1 (NKX2-1) mRNA expression in LUAD donor BCs. CONCLUSIONS: These and other findings demonstrate impacts of donor age, smoking, and lung cancer case-control status on BC phenotypic and molecular traits and may suggest Notch signaling pathway deregulation during early human lung cancer pathogenesis.

Development of a disulfidptosis-related lncRNA prognostic signature for enhanced prognostic assessment and therapeutic strategies in lung squamous cell carcinoma.

Limited treatment options and poor prognosis present significant challenges in the treatment of lung squamous cell carcinoma (LUSC). Disulfidptosis impacts cancer progression and prognosis. We developed a prognostic signature using disulfidptosis-related long non-coding RNAs (lncRNAs) to predict the prognosis of LUSC patients. Gene expression matrices and clinical information for LUSC were downloaded from the TCGA database. Co-expression analysis identified 209 disulfidptosis-related lncRNAs. LASSO-Cox regression analysis identified nine key lncRNAs, forming the basis for establishing a prognostic model. The model's validity was confirmed by Kaplan-Meier and ROC curves. Cox regression analysis identified the risk score (RS) as an independent prognostic factor inversely correlated with overall survival. A nomogram based on the RS demonstrated good predictive performance for LUSC patient prognosis. The relationship between RS and immune function was explored using ESTIMATE, CIBERSORT, and ssGSEA algorithms. According to the TIDE database, a negative correlation was found between RS and immune therapy responsiveness. The GDSC database revealed that 49 drugs were beneficial for the low-risk group and 25 drugs for the high-risk group. Silencing C10orf55 expression in SW900 cells reduced invasiveness and migration potential. In summary, this lncRNA model based on TCGA-LUSC data effectively predicts prognosis and assists clinical decision-making.

FOXA2 Activates RND1 to Regulate Arachidonic Acid Metabolism Pathway and Suppress Cisplatin Resistance in Lung Squamous Cell Carcinoma.

BACKGROUND: The primary cause of cancer-related fatalities globally is lung cancer. Although the chemotherapy drug cisplatin (DDP) has brought certain benefits to patients, the rapid development of drug resistance has greatly hindered treatment success. METHODS: We used the lung squamous cell carcinoma (LUSC) mRNA data set to explore the differentially expressed gene (RND1) in LUSC and detected RND1 expression in LUSC cells and DDP-resistant cells by qRT-PCR. Meanwhile, we performed abnormal expression treatment on RND1 and conducted CCK8, colony formation, and flow cytometry to evaluate the impact of RND1 expression on cell proliferation, apoptosis, and DDP resistance. In addition, we analyzed metabolism pathways involving RND1 using GSEA. We also used online tools such as hTFtarget and JASPAR to screen for the upstream transcription factor FOXA2 of RND1 and verified their relationship through CHIP and dual luciferase experiments. Finally, we validated the role of FOXA2-RND1 in DDP resistance in LUSC through the above experiments. RESULTS: RND1 was downregulated in LUSC, and overexpression of RND1 repressed proliferation and DDP resistance of LUSC cells and facilitated cell apoptosis. RND1 modulated the arachidonic acid (AA) metabolism pathway, and FOXA2 positively manipulated RND1 expression. By activating FOXA2, stabilizing RND1, and regulating AA levels, the sensitivity of LUSC cells to DDP could be enhanced. CONCLUSION: Our study suggested that FOXA2 positively modulated the RND1-AA pathway, which repressed the resistance of LUSC cells to DDP.

Sumo-regulatory SENP2 controls the homeostatic squamous mitosis-differentiation checkpoint.

Squamous or epidermoid cancer arises in stratified epithelia but also is frequent in the non-epidermoid epithelium of the lung by unclear mechanisms. A poorly studied mitotic checkpoint drives epithelial cells bearing irreparable genetic damage into epidermoid differentiation. We performed an RNA-sequencing gene search to target unknown regulators of this response and selected the SUMO regulatory protein SENP2. Alterations of SENP2 expression have been associated with some types of cancer. We found the protein to be strongly localised to mitotic spindles of freshly isolated human epidermal cells. Primary cells rapidly differentiated after silencing SENP2 with specific shRNAs. Loss of SENP2 produced in synchronised epithelial cells delays in mitotic entry and exit and defects in chromosomal alignment. The results altogether strongly argue for an essential role of SENP2 in the mitotic spindle and hence in controlling differentiation. In addition, the expression of SENP2 displayed an inverse correlation with the immuno-checkpoint biomarker PD-L1 in a pilot collection of aggressive lung carcinomas. Consistently, metastatic head and neck cancer cells that do not respond to the mitosis-differentiation checkpoint were resistant to depletion of SENP2. Our results identify SENP2 as a novel regulator of the epithelial mitosis-differentiation checkpoint and a potential biomarker in epithelial cancer.

Plasma extracellular vesicle long RNA profiling identifies a predictive signature for immunochemotherapy efficacy in lung squamous cell carcinoma.

Introduction: The introduction of Immune Checkpoint Inhibitors (ICIs) has marked a paradigm shift in treating Lung Squamous Cell Carcinoma (LUSC), emphasizing the urgent need for precise molecular biomarkers to reliably forecast therapeutic efficacy. This study aims to identify potential biomarkers for immunochemotherapy efficacy by focusing on plasma extracellular vesicle (EV)-derived long RNAs (exLRs). Methods: We enrolled 78 advanced LUSC patients undergoing first-line immunochemotherapy. Plasma samples were collected, and exLR sequencing was conducted to establish baseline profiles. A retrospective analysis was performed on 42 patients to identify differentially expressed exLRs. Further validation of the top differentially expressed exLRs was conducted using quantitative reverse transcription PCR (qRT-PCR). Univariate Cox analysis was applied to determine the prognostic significance of these exLRs. Based on these findings, we developed a predictive signature (p-Signature). Results: In the retrospective analysis of 42 patients, we identified 460 differentially expressed exLRs, with pathways related to leukocyte migration notably enriched among non-responders. Univariate Cox analysis revealed 45 exLRs with prognostic significance. The top 6 protein-coding exLRs were validated using qRT-PCR, identifying CXCL8, SSH3, and SDHAF1 as differentially expressed between responders and non-responders. The p-Signature, comprising these three exLRs, demonstrated high accuracy in distinguishing responders from non-responders, with an Area Under the Curve (AUC) of 0.904 in the retrospective cohort and 0.812 in the prospective cohort. Discussion: This study highlighted the potential of plasma exLR profiles in predicting LUSC treatment efficacy. Intriguingly, lower p-Signature scores were associated with increased abundance of activated CD4+ and CD8+ T cells, indicating a more robust immune environment. These findings suggest that the p-Signature could serve as a valuable tool in guiding personalized and effective therapeutic strategies for LUSC.

HPV- associated sinonasal squamous cell carcinoma with FGFR3::TACC3 fusion. A rare case report.

Sinonasal squamous cell carcinomas (SNSCCs) are uncommon and they are associated with adverse prognosis. HPV-associated SNSCCs and fusion-driven SNSCCs are particularly rare. A case of an HPV-associated SNSCC with a FGFR3::TACC3 fusion is thus presented; a brief review of the pertinent literature is also provided.

Proximity ligation-based sequencing for the identification of human papillomavirus genomic integration sites in formalin-fixed paraffin embedded oropharyngeal squamous cell carcinomas.

Human papillomavirus (HPV) infections are an increasing cause of oropharyngeal squamous cell carcinomas (OPSCC). Integration of the viral genome into the host genome is suggested to affect carcinogenesis, however, the correlation with OPSCC patient prognosis is still unclear. Research on HPV integration is hampered by current integration detection technologies and their unsuitability for formalin-fixed paraffin-embedded (FFPE) tissues. This study aims to develop and validate a novel targeted proximity-ligation based sequencing method (targeted locus amplification/capture [TLA/TLC]) for HPV integration detection in cell lines and FFPE OPSCCs. For the identification of HPV integrations, TLA/TLC was applied to 7 cell lines and 27 FFPE OPSCCs. Following preprocessing steps, a polymerase chain reaction (PCR)-based HPV enrichment was performed on the cell lines and a capture-based HPV enrichment was performed on the FFPE tissues before paired-end sequencing. TLA was able to sequence up to hundreds of kb around the target, detecting exact HPV integration loci, structural variants, and chromosomal rearrangements. In all cell lines, one or more integration sites were identified, in accordance with detection of integrated papillomavirus sequences PCR data and the literature. TLC detected integrated HPV in 15/27 FFPE OPSCCs and identified simple and complex integration patterns. In general, TLA/TLC confirmed PCR data and detected additional integration sites. In conclusion TLA/TLC reliably and robustly detects HPV integration in cell lines and FFPE OPSCCs, enabling large, population-based studies on the clinical relevance of HPV integration. Furthermore, this approach might be valuable for clonality assessment of HPV-related tumors in clinical diagnostics.

Expression and prognostic analysis of PFKFB4 in oral squamous cell carcinoma.

Fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase 4 (PFKFB4) is a crucial enzyme in the glycolysis pathway, possessing both kinase and phosphatase capabilities. Although it has emerged as an important oncogene in various cancer types, its function in oral squamous cell carcinoma (OSCC) is still not well understood. In our research, PFKFB4 expression was assessed via immunohistochemical (IHC) staining of tissue microarrays and OSCC patient specimens. The transcriptional expression of PFKFB4 in OSCC was analyzed by utilizing The Cancer Genome Atlas (TCGA) dataset. Correlation between PFKFB4 expression and clinicopathological features was examined using the χ2 test. Prognostic investigation of PFKFB4 was conducted via Kaplan-Meier and Cox analyses. PFKFB4 levels were notably elevated in OSCC samples in comparison to adjacent normal tissues (P < 0.001). Elevated PFKFB4 expression was associated with higher histologic grade (P = 0.0438), higher T stage (P = 0.031), and more advanced clinical stage (P = 0.0063). The ROC curve demonstrated the diagnostic potential of PFKFB4 (AUC = 0.827). Increased levels of PFKFB4 were linked to decreased overall survival (OS) (P = 0.04), poorer disease-specific survival (DSS) (P = 0.04), and shorter progression-free interval (PFI) (P < 0.001). PFKFB4 expression was identified as an independent risk factor for OS based on Cox regression analysis [hazard ratio (HR) = 1.517, P = 0.044)]. An OS nomogram was constructed with a concordance index of 0.690. Our findings reveal that upregulated PFKFB4 expression in OSCC tissues could serve as a potential prognostic biomarker.

p27 specifically decreases in squamous carcinoma, and mediates NNK-induced transformation of human bronchial epithelial cells.

Lung cancer remains the leading cause of cancer-related deaths, with cigarette smoking being the most critical factor, linked to nearly 90% of lung cancer cases. NNK, a highly carcinogenic nitrosamine found in tobacco, is implicated in the lung cancer-causing effects of cigarette smoke. Although NNK is known to mutate or activate certain oncogenes, its potential interaction with p27 in modulating these carcinogenic effects is currently unexplored. Recent studies have identified specific downregulation of p27 in human squamous cell carcinoma, in contrast to adenocarcinoma. Additionally, exposure to NNK significantly suppresses p27 expression in human bronchial epithelial cells. Subsequent studies indicates that the downregulation of p27 is pivotal in NNK-induced cell transformation. Mechanistic investigations have shown that reduced p27 expression leads to increased level of ITCH, which facilitates the degradation of Jun B protein. This degradation in turn, augments miR-494 expression and its direct regulation of JAK1 mRNA stability and protein expression, ultimately activating STAT3 and driving cell transformation. In summary, our findings reveal that: (1) the downregulation of p27 increases Jun B expression by upregulating Jun B E3 ligase ITCH, which then boosts miR-494 transcription; (2) Elevated miR-494 directly binds to 3'-UTR of JAK1 mRNA, enhancing its stability and protein expression; and (3) The JAK1/STAT3 pathway is a downstream effector of p27, mediating the oncogenic effect of NNK in lung cancer. These findings provide significant insight into understanding the participation of mechanisms underlying p27 inhibition of NNK induced lung squamous cell carcinogenic effect.

Micro RNA Dysregulation in Keratinocyte Carcinomas: Clinical Evidence, Functional Impact, and Future Directions.

The keratinocyte carcinomas, basal cell carcinoma (BCC), and cutaneous squamous cell carcinoma (cSCC), are the most common cancers in humans. Recently, an increasing body of literature has investigated the role of miRNAs in keratinocyte carcinoma pathogenesis, progression and their use as therapeutic agents and targets, or biomarkers. However, there is very little consistency in the literature regarding the identity of and/or role of individual miRNAs in cSCC (and to a lesser extent BCC) biology. miRNA analyses that combine clinical evidence with experimental elucidation of targets and functional impact provide far more compelling evidence than studies purely based on clinical findings or bioinformatic analyses. In this study, we review the clinical evidence associated with miRNA dysregulation in KCs, assessing the quality of validation evidence provided, identify gaps, and provide recommendations for future studies based on relevant studies that investigated miRNA levels in human cSCC and BCC. Furthermore, we demonstrate how miRNAs contribute to the regulation of a diverse network of cellular functions, and that large-scale changes in tumor cell biology can be attributed to miRNA dysregulation. We highlight the need for further studies investigating the role of miRNAs as communicators between different cell types in the tumor microenvironment. Finally, we explore the clinical benefits of miRNAs as biomarkers of keratinocyte carcinoma prognosis and treatment.

Impact of Human Papillomavirus on microRNA-21 Expression in Oral and Oropharyngeal Cancer-A Systematic Review.

Recently, microRNAs (miR) were identified to have potential links with oral squamous cell carcinoma (OSCC) and oropharyngeal squamous cell carcinoma (OPSCC) oncogenesis, specifically miR-21. Since HPV is a major risk factor for the development of these diseases, we aimed to search the literature regarding miR-21 expression in both HPV-positive and HPV-negative OSCC/OPSCC. The search was performed in the PubMed (MEDLINE), Scopus, Web of Science, and Cochrane electronic databases. The research question was as follows: Is there a difference in the tissue expression of miR-21 between patients with HPV-positive and those with HPV-negative OSCC/OPSCC? After conducting a meticulous search strategy, four studies were included, and they had a pooled sample size of 621 subjects with OSCC and/or OPSCC. Three studies did not find any significant difference in miR-21 expression between HPV-positive and HPV-negative OSCC/OPSCC. The findings of this systematic review showed that there are no differences in miR-21 expression between HPV-positive and HPV-negative OSCC/OPSCC. Nevertheless, it is worth noting that there are still insufficient studies regarding this important subject, because understanding how HPV influences miR-21 expression and its downstream effects can provide insights into the molecular mechanisms underlying OSCC/OPSCC development and progression.

Squamous Cell Carcinoma in Never Smokers: An Insight into SMARCB1 Loss.

Lung cancer remains the leading cause of cancer-related mortality worldwide, with non-small cell lung cancer (NSCLC) constituting 85% of cases. Among NSCLCs, squamous cell carcinoma (SqCC) is strongly associated with smoking. However, lung cancer in never smokers (LCINS) represents approximately 25% of lung cancer cases globally and shows increasing incidence, particularly in East Asia. LCINS-SqCC is less well-characterized, especially regarding its genomic alterations and their impact on clinical outcomes. We conducted a retrospective analysis over a 20-year period (July 2003-July 2023) at two major tertiary centers in the UK. The cohort included 59 patients with LCINS-SqCC who underwent radical surgical resection. Data collected included demographic information, comorbidities, histopathological details, and outcome metrics such as disease-free and overall survival. Molecular sequencing of tumor specimens was performed to identify genomic aberrations. The cohort had a median age of 71 years (IQR 62-77) and a median BMI of 25.4 (IQR 22.8-27.8), with a slight male predominance (53%). The majority of patients (93%) had a preoperative MRC of 1-2. Recurrent disease was observed in 23 patients (39%), and 32 patients (54%) had died at a median follow-up of 3 years. Median disease-free survival was 545 days (IQR 132-1496), and overall survival was 888 days (IQR 443-2071). Preoperative creatinine levels were higher in patients who experienced recurrence (p = 0.037). Molecular analysis identified biallelic SMARCB1 loss in two younger patients, associated with rapid disease progression despite R0 resection. These patients' tumors were PDL1-negative, TTF-1-negative, and positive for cytokeratin, CD56, and p40. SMARCB1-deficient SqCC in never smokers represents a highly aggressive variant with poor disease-free survival, highlighting the importance of integrating advanced molecular diagnostics in clinical practice. This study underscores the necessity for personalized treatment strategies, including targeted therapies such as EZH2 inhibitors and immune checkpoint blockade, to address the unique molecular pathways in SMARCB1-deficient cancers. Further clinical trials are essential to optimize therapeutic approaches for this challenging subgroup of lung cancer.