Mutational Status of CDKN2A and TP53 Genes in Laryngeal Squamous Cell Carcinoma

Molecular pathways modulated by phytochemicals in head and neck cancer

In the last few years, natural dietary phytochemicals have shown immense potential in the suppression and incidence of Head and Neck Cancer (HNC). From various in-vitro, animal, and epidemiological studies it is now clear that intake of foods rich in dietary phytochemicals lower the risk of HNC. These phytochemicals have been reported to target different stages of Head and Neck cancer (initiation to promotion) by modulating many cellular signaling pathways. A single phytochemical may target different pathways simultaneously or a single pathway may be targeted by a diversity of phytochemicals. This review highlights the molecular pathways modulated by a large number of phytochemicals relevant to HNC with an intent to identify specific signaling pathways that could be therapeutically targeted. Therefore, relevant literature was screened and scrutinized for molecular details. We have focused on the complexity of the molecular mechanisms that are modulated by various phytochemicals and the role they can play in better clinical efficacy and management of head and neck cancer. In-depth knowledge of these molecular mechanisms can lead to innovative therapeutic strategies using phytochemicals alone or along with available treatments for various cancers including HNC. Molecular pathways modulated by Phytochemicals.

Potential ferroptosis-related diagnostic and prognostic biomarkers in laryngeal cancer

PURPOSE

Laryngeal cancer (LC) is a common malignant tumor of the head and neck. However, the relationship between ferroptosis and LC is still unclear. The aim of this study was to identify potential ferroptosis-related biomarkers for diagnosis and prognosis in LC.

METHODS

We screened differentially expressed genes (DEGs) related to ferroptosis in LC from the TCGA and FerrDb database. DEGs were identified and enrichment by GO/KEGG, GSEA, GSVA analysis. PPI analysis was performed using String and Cytoscape, then hub genes were extracted. Furthermore, ROC analysis, pan-cancer analysis, gene mutation analysis, immune infiltration correlation analysis and clinical correlation analysis of hub genes were performed.

RESULTS

A total of 59 DEGs were screened, which were more significantly enriched in biological processes and involved in HIF-1 signaling pathway, serotonergic synapse and ferroptosis. A total of 29 significant gene set pathways of LC data were performed by GSEA analysis. The GSVA analysis obtained 53 significant differential gene set pathways. The top 20 genes were identified by PPI. ROC curves revealed four of the top20 genes had a good performance, which were CA9 (AUC = 0.930), MAPK3 (AUC = 0.915), MUC1 (AUC = 0.945), and NOX4 (AUC = 0.933). Subsequent analysis found that CDKN2A has the highest mutation frequency in the top 20 gene, and IFNG had a significant correlation with age, tumor stage, degree of tumor differentiation and lymphatic clearance surgery.

CONCLUSION

Our study identified key genes closely related to ferroptosis in LC, which still need more studies to explore the mechanisms involved and may become effective clinical diagnostic and prognostic biomarkers.

Systemic Analysis on the Features of Immune Microenvironment Related to Prognostic Signature in Head and Neck Squamous Cell Carcinoma

Background: Head and neck squamous cell carcinoma's tumor immune microenvironment (TIME) plays an important role in tumorigenesis and progression, but its clinical significance remains unclear. Therefore, the TIME needs to be better understood in order to improve the response of diagnosis and therapy. Methods: The gene expression and clinical data of 569 HNSCC patients were obtained from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). Immune-related genes (IRGs) from the ImmPort database were used for immunotyping of HNSCC patients, and independent GEO datasets were used for subtype verification and comprehensive molecular identification. Results: The patients were divided into three subtypes (C1, C2, and C3) related to different gene expression profiles. The three subtypes showed widely different patterns in tumor genetic distortion, immune cell composition, cytokine profile, and so on, verifying that the immune-enhanced C2 subtype was associated with better prognosis. In addition, the stroma-deficient C1 subtype may be more efficient for the immune response than the C3 subtype. Furthermore, using WGCNA on the IRGs of those three subtypes, we found two C2-positive gene modules closely related to infection- and immune-associated pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database, and the two modules had 22 common pathways. Conclusion: This study improves the power for prognosis prediction and develops new therapeutic strategies to stratify HNSCC patients into clinically significant groups through TIME-related prognostic signature.

Overview on Molecular Biomarkers for Laryngeal Cancer: Looking for New Answers to an Old Problem

Laryngeal squamous cell cancer (LSCC) accounts for almost 25-30% of all head and neck squamous cell cancers and is clustered according to the affected districts, as this determines distinct tendency to recur and metastasize. A major role for numerous genetic alterations in driving the onset and progression of this neoplasm is emerging. However, major efforts are still required for the identification of molecular markers useful for both early diagnosis and prognostic definition of LSCC that is still characterized by significant morbidity and mortality. Non-coding RNAs appear the most promising as they circulate in all the biological fluids allowing liquid biopsy determination, as well as due to their quick and characteristic modulation useful for non-invasive detection and monitoring of cancer. Other critical aspects are related to recent progress in circulating tumor cells and DNA detection, in metastatic status and chemo-refractoriness prediction, and in the functional interaction of LSCC with chronic inflammation and innate immunity. We review all these aspects taking into account the progress of the technologies in the field of next generation sequencing.

Molecular Pathways and Druggable Targets in Head and Neck Squamous Cell Carcinoma

Head and neck cancers are a heterogeneous group of neoplasms, affecting an ever increasing global population. Despite advances in diagnostic technology and surgical approaches to manage these conditions, survival rates have only marginally improved and this has occurred mainly in developed countries. Some improvements in survival, however, have been a result of new management and treatment approaches made possible because of our ever-increasing understanding of the molecular pathways triggered in head and neck oncogenesis, and the growing understanding of the abundant heterogeneity of this group of cancers. Some important pathways are common to other solid tumours, but their impact on reducing the burden of head and neck disease has been less than impressive. Other less known and little-explored pathways may hold the key to the development of potential druggable targets. The extensive work carried out over the last decade, mostly utilising next generation sequencing has opened up the development of many novel approaches to head and neck cancer treatment. This paper explores our current understanding of the molecular pathways of this group of tumours and outlines associated druggable targets which are deployed as therapeutic approaches in head and neck oncology with the ultimate aim of improving patient outcomes and controlling the personal and economic burden of head and neck cancer.

A rare multiple primary sarcomatoid carcinoma (SCA) of small intestine harboring driver gene mutations: a case report and a literature review

Primary sarcomatoid carcinoma (SCA) is a type of rare tumor consisting of both malignant epithelial and mesenchymal components. Only 32 cases of SCA of the small bowel have been reported in the literature to date. Due to its rarity and complexity, this cancer has not been genetically studied and its diagnosis and treatment remain difficult. Here we report a 54-year-old male underwent emergency surgical resection in the small intestine due to severe obstruction and was diagnosed with multiple SCA based on postoperative pathological examination. Over 100 polypoid tumors scattered along his whole jejunum and proximal ileum. Chemotherapy (IFO+Epirubicin) was performed after surgery while the patient died two months after the surgery due to severe malnutrition. Whole-exome sequencing was performed for the tumor tissue with normal tissue as the control. Important cancer-related gene mutations, including KRAS (c.37G>T, p.G13C), TP53 (c.871A>T, p.K291*), EGFR (c.1351C>T, p.R451C), and CDKN2A (c.104_138del, p.G35fs), were found among 286 nonsynonymous somatic mutations (SNV and Indel). Copy-number amplified genes mainly gathered in chromosome 6, 7, 16 and 20. Mutation clustering analysis showed that main genetic abnormalities included DNA methylation, DNA alkylation, cellular homeostasis, and shared similarities with melanoma, glioma, prostate cancer, bladder cancer, non-small cell lung cancer, and pancreatic cancer. In summary, the genomic features of the small intestine SCA were explored at whole-exome level for the first time, and over 200 somatic mutations were identified in the tumor tissue. Key tumor driver gene mutations were revealed, as well as several aberrant functional pathways. These results contribute to further understanding of the pathogenesis and molecular mechanism of this rare tumor.

MMP2/3 promote the growth and migration of laryngeal squamous cell carcinoma via PI3K/Akt-NF-κB-mediated epithelial-mesenchymal transformation

Laryngeal squamous cell carcinoma (LSCC) is an aggressive malignancy with metastatic potential and high mortality worldwide. Matrix metalloproteinases (MMPs) are a group of extracellular proteolytic enzymes. Although MMPs have been proved to be essential in the process of tumor migration and metastasis in most types of carcinomas, the expression and function of MMP2/3 in LSCC remain unknown. Here, we investigated the roles of MMP2/3 in LSCC and elucidated the underlying mechanism. We found that levels of MMP2/3 were significantly higher in clinical LSCC samples than in paired normal sample examined by real-time polymerase chain reaction and western blot assays. Moreover, overexpression of MMP2/3 promoted the proliferation and migration of LSCC cells by Cell Counting Kit-8, transwell, and scratch wound-healing assays in vitro. Furthermore, levels of epithelial cell markers (E-cadherin and occludin) were decreased following MMP2/3 overexpression, with increased levels of mesenchymal cell markers (N-cadherin and vimentin), suggesting the involvement of epithelial-mesenchymal transformation (EMT) process in MMP2/3-mediated LSCC cell migration. By using short hairpin RNA, knockdown of MMP2/3 expression inhibited the proliferation, migration, and EMT process in LSCC cells in vitro. More importantly, we confirmed that MMP2/3 promoted LSCC in the PI3K/Akt-NF-κB-dependent manner. This study provides insight into MMP2/3-mediated LSCC development and lays a foundation for potential pharmacological targets to LSCC.

LncRNA MEG3 inhibits cell proliferation and induces apoptosis in laryngeal cancer via miR-23a/APAF-1 axis

Long non‐coding RNA (LncRNA) MEG3 serves a regulatory role in the progression of several types of cancer, but the role of MEG3 in laryngeal cancer is still unknown. The aim of this study was to explore the regulatory role and mechanism of MEG3 in laryngeal cancer. MEG3 expression in 50 laryngeal cancer tissue samples was detected by reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR). The effects of MEG3 overexpression on laryngeal cancer cells were investigated in vitro and in vivo. The mechanism of competitive endogenous RNA (ceRNA) was validated through luciferase reporter assay, RT‐qPCR and Western blotting. MEG3 was down‐regulated in laryngeal cancer tissues, and the low MEG3 expression was associated with advanced clinical stage. Additionally, MEG3 overexpression inhibited the proliferation and induced the apoptosis of laryngeal cancer cells in vitro and in vivo. Particularly, MEG3 bound to miR‐23a specifically and a reciprocal negative regulation existed between miR‐23a and MEG3. Moreover, MEG3 up‐regulated apoptotic protease activating factor‐1 (APAF‐1), a known miR‐23a's target, thereby leading to the activation of caspase‐9 and caspase‐3. Meanwhile, these activated effects were rescued by miR‐23a overexpression. In conclusion, the present study demonstrated that MEG3 functions as a novel tumour suppressive LncRNA in laryngeal cancer for the first time. Furthermore, MEG3 may act as a ceRNA to regulate APAF‐1 expression by competitive binding to miR‐23a, thereby regulating the progression of laryngeal cancer.

Novel genetic alterations and their impact on target therapy response in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is highly variable by tumor site, histologic type, molecular characteristics, and clinical outcome. During recent years, emerging targeted therapies have been focused on driver genes. HNSCC involves several genetic alterations, such as co-occurrence, multiple feedback loops, and cross-talk communications. These different kinds of genetic alterations interact with each other and mediate targeted therapy response. In the current review, it is emphasized that future treatment strategy in HNSCC will not solely be based on "synthetic lethality" approaches directed against overactivated genes. More importantly, biologic, genetic, and epigenetic alterations of HNSCC will be taken into consideration to guide the therapy. The emerging genetic alterations in HNSCC and its effect on targeted therapy response are discussed in detail. Hopefully, novel combination regimens for the treatment of HNSCC can be developed.