NOTCH1 Signaling in Head and Neck Squamous Cell Carcinoma

Molecular features of T and N stage progression in laryngeal cancer

Laryngeal squamous cell cancer (LSCC) is a common type of head and neck cancer that is typically unrelated to human papilloma virus (HPV) infection. Late-stage laryngeal cancers are associated with greater morbidity due to obstructive symptoms, and poorer overall survival. Using data from The Cancer Genome Atlas (TCGA), we analyzed 112 patient LSCC samples, comparing patient proteome, transcriptome and genome between early and late T and N samples. We observed significant differences in SNV frequency for various genes between the early and late-stage groups. Most notably we observed that NOTCH1 mutation, which was more frequent in late N-stage supraglottic cancers, was also associated with poorer patient survival in LSCCs. Methylation analysis also revealed changes in JUN gene methylation in late N glottic cancers. Transcriptomic analysis revealed differential expression in c-JUN, HOXB7 and HOXB9 transcript levels, suggesting potential involvement of these pathways in progression and nodal involvement. Our findings illustrate that LSCC undergoes distinct molecular changes associated with different stages and subsites. We observed multiple potential markers for progression, metastases and survival, including NOTCH1 mutation, which may aid as prognostic indicators in future studies.

Altered TP53, CDKN2A, ATM, EPHA7, POT1, CHEK1, GRIN2A, and EGFR Predict Shorter Survival in Penile Squamous Cell Carcinoma

Penile squamous cell carcinoma (pSCC) represents an uncommon malignancy characterized by stagnant mortality, psychosexual distress, and a highly variable prognosis. Currently, the World Health Organization distinguishes between human papillomavirus (HPV)-related and HPV-independent pSCC. Recently, there has been an evolving line of research documenting the enrichment of HPV-independent pSCC with a high tumor mutational burden (TMB) and programmed death ligand-1 expression, as well as clusters of genes associated with HPV status. In this study, we conducted comprehensive next-generation sequencing DNA profiling of 146 pSCC samples using a panel consisting of 355 genes associated with tumors. This profiling was correlated with immunohistochemical markers and prognostic clinical data. A survival analysis of recurrent genomic events (found in ≥10 cases) was performed. TP53, CDKN2A, ATM, EPHA7, POT1, CHEK1, GRIN2A, and EGFR alterations were associated with significantly shortened overall survival in univariate and multivariate analysis. HPV positivity, diagnosed through both p16 immunohistochemistry and HPV DNA analysis, displayed no impact on survival but was associated with high-grade, lymphatic invasion, programmed death ligand-1 negativity/weak expression, and low TMB. FAT1, TP53, CDKN2A, CASP8, and HRAS were more often mutated in HPV-independent pSCC. In contrast, HPV-associated pSCCs were enriched by EPHA7, ATM, GRIN2A, and CHEK1 mutations. PIK3CA, FAT1, FBXW7, and KMT2D mutations were associated with high TMB. NOTCH1, TP53, CDKN2A, POT1, KMT2D, ATM, CHEK1, EPHA3, and EGFR alterations were related to adverse clinicopathologic signs, such as advanced stage, high tumor budding, and lymphovascular invasion. We detected 160 alterations with potential treatment implications, with 21.2% of samples showing alterations in the homologous recombination repair pathway. To the best of our knowledge, this study describes the largest cohort of pSCC with complex molecular pathologic, clinical, and prognostic analysis correlating with prognosis.

A Carbon-Based Nanomaterial with Dichotomous Effects: Antineoplastic on Oral Cancer Cells and Osteoinductive/Chondroinductive on Dental Pulp Stem Cells

BACKGROUND

Oral cancer is an aggressive malignancy with modest survival rates. It also causes disfigurement following surgical removal of the tumor, thus highlighting the need for new cancer treatment and tissue repair modalities. Carbon-based nanomaterials have emerged as promising tools in both anticancer and regenerative therapies.

OBJECTIVES

We aimed to synthesize a new carbon-based nanomaterial (CBN) and test its antineoplastic effects, as well as its potential regenerative capacity.

MATERIALS AND METHODS

A carbon nanomaterial, obtained by ball milling graphite flakes, was functionalized with polyvinylpyrrolidone (CBN/PVP). Its physicochemical properties were explored with X-ray diffraction (XRD), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), micro-Raman spectroscopy, fluorescent and scanning electron microscopy, and wettability analysis. For the antineoplastic effects investigation, oral cancer cells were treated with CBN/PVP and examined with MTT and migration assays, as well as cell-cycle and ROS production analyses. Gene expression was determined by qPCR. To examine the pro-regenerative capacity of CBN/PVP, dental pulp stem cell cultures (DPSCs) were treated with the nanomaterial and subjected to osteo- and chondro-induction.

RESULTS

Lower concentrations of CBN/PVP (50, 100 μg/mL) applied on cancer cells exerted remarkable cytotoxic effects, induced G1 cell-cycle arrest, and reduced cancer cell invasion potential by different mechanisms, including downregulation of the PI3K/AKT/mTOR pathway. In contrast, the addition of 50 µg/mL of CBN/PVP to DPSCs stimulated their survival and proliferation. CBN/PVP significantly enhanced both the osteogenic (p < 0.05) and chondrogenic (p < 0.01) induction of DPSCs.

CONCLUSIONS

The novel carbon-based nanomaterial displays unique characteristics, making it suitable in anticancer and regenerative therapies concomitantly.

WBP5 Expression Influences Prognosis and Treatment Response in Head and Neck Squamous Cell Carcinoma

OBJECTIVES

Head and neck squamous cell carcinoma (HNSCC) is characterized by complex genetic alterations. This study aimed to identify WBP5 as a promising therapeutic target and evaluate the effect of WBP5 expression on prognosis and treatment response in HNSCC.

METHODS

Publicly available datasets were comprehensively analyzed to investigate WBP5 expression through comprehensive bioinformatics analysis and functional validation.

RESULTS

WBP5 was particularly overexpressed in HNSCC, as analyzed through the Gene Expression Profiling Interactive Analysis version 2 (GEPIA2) database and validated using multiple Gene Expression Omnibus (GEO) datasets. Analysis with UALCAN confirmed that WBP5 expression was significantly higher in advanced cancer stages and tumor grades than that of normal samples. A Kaplan-Meier analysis demonstrated that patients overexpressing WBP5 had a poor prognosis. Moreover, WBP5 expression correlated with the overexpression of the epidermal growth factor receptor in HNSCC. In vitro experiments revealed that WBP5 knockdown significantly reduced FaDu cell proliferation and viability. Furthermore, silencing WBP5 enhanced cisplatin sensitivity, indicating its potential role in chemoresistance.

CONCLUSIONS

These results indicate that WBP5 could act as a prognostic marker and a viable therapeutic target in HNSCC. Modulating WBP5 expression may represent a novel strategy to enhance treatment efficacy. Future studies should elucidate the precise mechanisms of WBP5 action and develop targeted therapies. This integrated approach, combining a comprehensive analysis of publicly available datasets with in vitro experimental validation provides strong evidence for the clinical significance of WBP5 in HNSCC.

Bypassing cisplatin resistance in Nrf2 hyperactivated head and neck cancer through effective PI3Kinase targeting

Background

For patients with head and neck squamous cell carcinoma (HNSCC), failure of definitive radiation combined with cisplatin nearly universally results in death. Although hyperactivation of the Nrf2 pathway can drive radiation and cisplatin resistance along with suppressed anti-tumor immunity, treatment-refractory HNSCC tumors may retain sensitivity to targeted agents secondary to synergistic lethality with other oncogenic drivers (e.g., NOTCH1 mutations).

Purpose

We evaluated the efficacy of PI3K inhibitors (PI3Ki) in bypassing Nrf2-mediated cisplatin resistance in HNSCC.

Methods

We measured transcriptomic, metabolomic and signaling changes driven by PI3Kis in cisplatin-resistant HNSCCs in vitro and tested efficacy in vivo in subcutaneous, orthotopic and metastatic xenograft models using immunodeficient and humanized murine models of HNSCC coupled with spatial transcriptomics.

Results

The PI3K pathway is activated in Nrf2-driven cisplatin-resistant HNSCC and is suitable for blockade as demonstrated in an in vivo shRNA screen. The PI3Ki gedatolisib inhibits cisplatin-resistant HNSCC proliferation, induces G2M arrest and potentiates cisplatin effectiveness through activation of autophagy, senescence and disruption of fatty acid metabolism. Gedatolisib suppresses HNSCC tumor growth in orthotopic and metastatic settings and demonstrates profound anti-tumor activity in humanized murine models of HNSCC, coupled with a reduction in hypoxia-rich regions and reduced infiltration by regulatory T lymphocytes.

Conclusion

Our findings emphasize the critical role of the PI3K-AKT-mTOR pathway in cisplatin-resistant HNSCC and highlight the therapeutic potential of PI3K inhibitors. Gedatolisib induced metabolic regulation and substantial re-sensitization of resistant cells to cisplatin, positioning it as a promising candidate for combination therapies aimed at overcoming primary chemo-radiation failure in HNSCC.

NOTCH1 regulates the DNA damage response and sorafenib resistance by activating ATM in hepatocellular carcinoma

OBJECTIVE

This study investigates the mechanism underlying sorafenib resistance in hepatocellular carcinoma cells (HCC), focusing on DNA damage repair (DDR) pathways to develop targeted therapeutic strategies.

METHODS

Bioinformatics analysis was used to screen genes associated with sorafenib resistance, which was further demonstrated by western blotting. Cell proliferation was determined using the EdU assay. The presence of binding sites between valproic acid (VPA) and NOTCH1 was analyzed by molecular docking. Comet and flow cytometry assays evaluated DNA damage and cell cycle arrest induced by VPA in sorafenib-resistant cells, with further mechanistic insights gained via western blotting and co-immunoprecipitation (Co-IP).

RESULTS

We found that NOTCH1/ATM axis plays a vital role in the prognosis of patients with liver cancer and in the behavior of sorafenib-resistant cells. HCC resistant to sorafenib exhibited enhanced cell proliferation ability. Moreover, overexpression of NOTCH1 in sorafenib-sensitive HCC cells significantly increased liver cancer cell proliferation. Conversely, silencing NOTCH1 expression in sorafenib-resistant HCC cell lines reduced their proliferative activity. Additionally, VPA enhanced the therapeutic efficacy against sorafenib-resistance cells by modulating NOTCH1/ATM/p-BRCA1/p-CHK2/γ-H2AX signaling axis and homologous recombination (HR) activity.

CONCLUSION

Targeting NOTCH1 and ATM is a promising strategy to overcome sorafenib resistance in HCC, particularly through the combined use of VPA and sorafenib.

Eco-corona enhanced the interactive effects of nanoplastics and 6:2 chlorinated polyfluorinated ether sulfonate in zebrafish embryos

Nanoplastics (NPs, < 1000 nm) interact with chemicals and biomolecules to produce chemical-/eco-corona, altering the environmental destiny, bioavailability, and toxicity of plastic particles and co-occurring chemicals. This study employs exogenous (humic acid, HA) and endogenous (bovine serum albumin, BSA) natural organic matter (NOM) to investigate the eco-corona formation on NPs and explore the interfacial effects of eco-corona and 6:2 chlorinated polyfluorinated ether sulfonate (Cl-PFESA, commonly named as F-53B) on zebrafish (Danio rerio) after 7 days of exposure. Our results indicated significant changes in growth and developmental indices of zebrafish embryos among all eco-corona groups (p < 0.05). Additionally, NFB (BSA-corona, 1 mg/L NPs + 200 μg/L F-53B + 10 mg/L BSA), NFH (HA-corona, 1 mg/L NPs + 200 μg/L F-53B + 10 mg/L HA) and NFHB (BSA-HA-corona, 1 mg/L NPs + 200 μg/L F-53B + 10 mg/L BSA + 10 mg/L HA) showed elevated bioaccumulation of NPs, ROS generation and induction of apoptosis. Transcriptomic analysis showed the number of differentially expressed genes (DEGs) in the following order: BSA-HA-corona (NFHB (2953) > HA-corona (NFH (2797) > NH (2721) > F-53B (2292) > NF (2033) > BSA-corona (NFB (687) > NB (450)), and no DEGs were detected in the single NP compared to the control. Further, the PI3K-AKT, immune system, endocrine system, digestive system, infectious diseases, and neurovegetative disease pathways showed sensitive responses in the NFH/NFHB groups compared to those in the NFB group. Therefore, the interactive effects of NPs and F-53B on zebrafish embryos were lower in the presence of BSA-corona than those in HA- or HA-BSA-coronas, indicating a relationship between the formation of diverse eco-coronas on NPs by multiple NOM and an associated increase in the interfacial toxicological effects of plastic particles and F-35B in freshwater organisms.

Epithelial‑derived head and neck squamous tumourigenesis (Review)

Head and neck squamous cell carcinomas (HNSCCs), a heterogeneous group of cancers that arise from the mucosal epithelia cells in the head and neck areas, present great challenges in diagnosis, treatment and prognosis due to their complex aetiology and various clinical manifestations. Several factors, including smoking, alcohol consumption, oncogenic genes, growth factors, Epstein‑Barr virus and human papillomavirus infections can contribute to HNSCC development. The unpredictable tumour microenvironment adds to the complexity of managing HNSCC. Despite significant advances in therapies, the prediction of outcome after treatment for patients with HNSCC remains poor, and the 5‑year overall survival rate is low due to late diagnosis. Early detection greatly increases the chances of successful treatment. The present review aimed to bring together the latest findings related to the molecular mechanisms of HNSCC carcinogenesis and progression. Comprehensive genomic, transcriptomic, metabolomic, microbiome and proteomic analyses allow researchers to identify important biological markers such as genetic alterations, gene expression signatures and protein markers that drive HNSCC tumours. These biomarkers associated with the stages of initiation, progression and metastasis of cancer are useful in the management of patients with cancer in order to improve their life expectancy and quality of life.

Notch1 Phase Separation Coupled Percolation facilitates target gene expression and enhancer looping

The Notch receptor is a pleiotropic signaling protein that translates intercellular ligand interactions into changes in gene expression via the nuclear localization of the Notch intracellular Domain (NICD). Using a combination of immunohistochemistry, RNA in situ, Optogenetics and super-resolution live imaging of transcription in human cells, we show that the N1ICD can form condensates that positively facilitate Notch target gene expression. We determined that N1ICD undergoes Phase Separation Coupled Percolation (PSCP) into transcriptional condensates, which recruit, enrich, and encapsulate a broad set of core transcriptional proteins. We show that the capacity for condensation is due to the intrinsically disordered transcriptional activation domain of the N1ICD. In addition, the formation of such transcriptional condensates acts to promote Notch-mediated super enhancer-looping and concomitant activation of the MYC protooncogene expression. Overall, we introduce a novel mechanism of Notch1 activity in which discrete changes in nuclear N1ICD abundance are translated into the assembly of transcriptional condensates that facilitate gene expression by enriching essential transcriptional machineries at target genomic loci.

The role of cells and their derivatives in otorhinolaryngologic diseases treatment

Otolaryngology is an important specialty in the field of surgery that deals with the diagnosis and treatment of the ear, nose, throat, trachea, as well as related anatomical structures. Various otolaryngological disorders are difficult to treat using established pharmacological and surgical approaches. The advent of molecular and cellular therapies led to further progress in this respect. This article reviews the therapeutic strategies of using stem cells, immune cells, and chondrocytes in otorhinolaryngology. As the most widely recognized cell derivatives, exosomes were also systematically reviewed for their therapeutic potential in head and neck cancer, otitis media, and allergic rhinitis. Finally, we summarize the limitations of stem cells, chondrocytes, and exosomes, as well as possible solutions, and provide an outlook on the future direction of cell- and derivative-based therapies in otorhinolaryngology, to offer a theoretical foundation for the clinical translation of this therapeutic modality.

Notch1 Phase Separation Coupled Percolation facilitates target gene expression and enhancer looping

The Notch receptor is a pleiotropic signaling protein that translates intercellular ligand interactions into changes in gene expression via the nuclear localization of the Notch intracellular Domain (NICD). Using a combination of immunohistochemistry, RNA in situ, Optogenetics and super-resolution live imaging of transcription in human cells, we show that the N1ICD can form condensates that positively facilitate Notch target gene expression. We determined that N1ICD undergoes Phase Separation Coupled Percolation (PSCP) into transcriptional condensates, which recruit, enrich, and encapsulate a broad set of core transcriptional proteins. We show that the capacity for condensation is due to the intrinsically disordered transcriptional activation domain of the N1ICD. In addition, the formation of such transcriptional condensates acts to promote Notch-mediated super enhancer-looping and concomitant activation of the MYC protooncogene expression. Overall, we introduce a novel mechanism of Notch1 activity in which discrete changes in nuclear N1ICD abundance are translated into the assembly of transcriptional condensates that facilitate gene expression by enriching essential transcriptional machineries at target genomic loci.

The Notch inhibitor, FLI-06, increases the chemosensitivity of head and neck Squamous cell carcinoma cells to taxanes-based treatment

Aberration of Notch signaling is one of the key events involved in the development and progression of head and neck squamous cell carcinoma (HNSCC). The Notch pathway controls the tissue-specific differentiation of normal squamous epithelial cells and is frequently altered in squamous carcinomas, thus affecting their proliferation, growth, survival, and chemosensitivity or resistance against anti-cancer agents. In this study, we show that the use of novel, small-molecule inhibitors of Notch signaling, such as FLI-06, can have a beneficial effect on increasing the chemosensitivity of HNSCC to taxane-based chemotherapy. Inhibition of Notch signaling by FLI-06 alone virtually blocks the proliferation and growth of HNSCC cells in both 2D and 3D cultures and the zebrafish model, which is accompanied by down-regulation of key Notch target genes and proteins. Mechanistically, FLI-06 treatment causes cell cycle arrest in the G1-phase and induction of apoptosis in HNSCC, which is accompanied by increased c-JunS63 phosphorylation. Combining FLI-06 with Docetaxel shows a synergistic effect and partially blocks the cell growth of aggressive HNSCC cells via enhanced apoptosis and modification of c-JunS243 phosphorylation via GSK-3β inhibition. In conclusion, inhibition of Notch signaling in HNSCC cells that retain active Notch signaling significantly supports taxane-based anticancer activities via modulation of both the GSK-3β and the c-Jun.

Molecular pathways and targeted therapies in head and neck cancers pathogenesis

The substantial heterogeneity exhibited by head and neck cancer (HNC), encompassing diverse cellular origins, anatomical locations, and etiological contributors, combined with the prevalent late-stage diagnosis, poses significant challenges for clinical management. Genomic sequencing endeavors have revealed extensive alterations in key signaling pathways that regulate cellular proliferation and survival. Initiatives to engineer therapies targeting these dysregulated pathways are underway, with several candidate molecules progressing to clinical evaluation phases, including FDA approval for agents like the EGFR-targeting monoclonal antibody cetuximab for K-RAS wild-type, EGFR-mutant HNSCC treatment. Non-coding RNAs (ncRNAs), owing to their enhanced stability in biological fluids and their important roles in intracellular and intercellular signaling within HNC contexts, are now recognized as potent biomarkers for disease management, catalyzing further refined diagnostic and therapeutic strategies, edging closer to the personalized medicine desideratum. Enhanced comprehension of the genomic and immunological landscapes characteristic of HNC is anticipated to facilitate a more rigorous assessment of targeted therapies benefits and limitations, optimize their clinical deployment, and foster innovative advancements in treatment approaches. This review presents an update on the molecular mechanisms and mutational spectrum of HNC driving the oncogenesis of head and neck malignancies and explores their implications for advancing diagnostic methodologies and precision therapeutics.

Targeting the ZMIZ1-Notch1 signaling axis for the treatment of tongue squamous cell carcinoma

Zinc finger MIZ-type containing 1 (ZMIZ1) is a transcriptional coactivator related to the protein inhibitors of activated STATs (PIAS) family. Mounting evidence suggests that ZMIZ1 plays a crucial role in the occurrence and development of cancers. The function of ZMIZ1 in tongue squamous cell carcinoma (TSCC) and the mechanisms underpinning its role in this disease have not been fully clarified. We performed qualitative ZMIZ1 protein expression analyses using immunohistochemistry in 20 patient-derived, paraffin-embedded TSCC tissue sections. We used RNAi to knock down ZMIZ1 expression in the CAL-27 TSCC cell line and quantified the impact of ZMIZ1 knock down on proliferation, migration and apoptosis via CCK-8, scratch assay and flow cytometry, respectively. We used qRT-PCR and western blotting to investigate the role of ZMIZ1 in this cell line. Finally, we established a model of lung metastasis in nude mice to replicate the in vitro results. ZMIZ1 protein was significantly more abundant in TSCC case tissue samples. ZMIZ1 knockdown reduced the invasion and metastases of TSCC tumor cells and promoted apoptosis. ZMIZ1 knockdown was associated with the down-regulation of Notch signaling pathway related factors Jagged1 and Notch1, and invasion and metastasis related factors MKP-1, SSBP2 and MMP7 in vitro and in vivo, at the mRNA level. In vitro and in vivo data suggest that knock down of ZMIZ1 may inhibit TSCC invasion and metastasis by modulating Notch signaling. ZMIZ1 inhibition may therefore represent a new therapeutic target for TSCC.

Notch signaling pathway in cancer: from mechanistic insights to targeted therapies

Notch signaling, renowned for its role in regulating cell fate, organ development, and tissue homeostasis across metazoans, is highly conserved throughout evolution. The Notch receptor and its ligands are transmembrane proteins containing epidermal growth factor-like repeat sequences, typically necessitating receptor-ligand interaction to initiate classical Notch signaling transduction. Accumulating evidence indicates that the Notch signaling pathway serves as both an oncogenic factor and a tumor suppressor in various cancer types. Dysregulation of this pathway promotes epithelial-mesenchymal transition and angiogenesis in malignancies, closely linked to cancer proliferation, invasion, and metastasis. Furthermore, the Notch signaling pathway contributes to maintaining stem-like properties in cancer cells, thereby enhancing cancer invasiveness. The regulatory role of the Notch signaling pathway in cancer metabolic reprogramming and the tumor microenvironment suggests its pivotal involvement in balancing oncogenic and tumor suppressive effects. Moreover, the Notch signaling pathway is implicated in conferring chemoresistance to tumor cells. Therefore, a comprehensive understanding of these biological processes is crucial for developing innovative therapeutic strategies targeting Notch signaling. This review focuses on the research progress of the Notch signaling pathway in cancers, providing in-depth insights into the potential mechanisms of Notch signaling regulation in the occurrence and progression of cancer. Additionally, the review summarizes pharmaceutical clinical trials targeting Notch signaling for cancer therapy, aiming to offer new insights into therapeutic strategies for human malignancies.

Common skin cancers and their association with other non-cutaneous primary malignancies: a review of the literature

It has long been recognized that a history of skin cancer puts one at risk for additional primary skin cancers. However, more variable data exists for the risk of developing a non-cutaneous primary cancer following a diagnosis of skin cancer. The data are most variable for Basal Cell Carcinoma (BCC), the most common and least aggressive type of skin cancer. While early studies imply that BCC does not impart a larger risk of other primary non-cutaneous cancers, more recent studies with larger populations suggest otherwise. The cancers most significantly associated with BCC are lip, oropharyngeal, and salivary gland cancer. There is also burgeoning evidence to suggest a link between BCC and prostate, breast, and colorectal cancer, but more data are needed to draw a concrete conclusion. Squamous Cell Carcinoma (SCC), the second most common type of skin cancer, has a slightly more defined risk to other non-cutaneous primary malignancies. There is a notable link between SCC and non-Hodgkin's lymphoma (NHL), possibly due to immunosuppression. There is also an increased risk of other cancers derived from squamous epithelium following SCC, including oropharyngeal, lip, and salivary gland cancer. Some studies also suggest an increased risk of respiratory tract cancer following SCC, possibly due to shared risk factors. Melanoma, a more severe type of skin cancer, shows a well-defined risk of additional primary non-cutaneous malignancies. The most significant of these risks include NHL, thyroid cancer, prostate cancer, and breast cancer along with a host of other cancers. Each of these three main skin cancer types has a profile of genetic mutations that have also been linked to non-cutaneous malignancies. In this review, we discuss a selection of these genes to highlight the complex interplay between different tumorigenesis processes.

Molecular characterization of the evolution of premalignant lesions in the upper aerodigestive tract

Introduction

Early relapse and development of metastatic disease are some of the primary reasons for the poor prognosis of patients with head and neck squamous cell carcinoma (HNSCC). HNSCC is a heterogeneous disease which may develop in large premalignant fields of genetically altered cells. Yet knowing which individuals will progress and develop clinically significant cancers during their lifetimes remains one of the most important challenges of reducing HNSCC morbidity and mortality. To further elucidate the molecular mechanisms, we performed a focused analysis of the genome and immune microenvironment from multiple, matched normal squamous tissue, premalignant lesions, as well as primary and recurrent tumors from seven patients with p16-negative HNSCC.

Methods

We performed targeted panel Next Generation Sequencing (161 genes) to analyze somatic variants from sequentially collected, matched formalin-fixed paraffin-embedded tissue (normal, premalignant, HNSCC) from two patients. These samples plus samples from five additional patients were analyzed with the Nanostring PanCancer Immune Panel. In addition, we performed shallow whole genome sequencing (0.5x coverage on average) on samples from three of these patients. Patients were, apart from one case, primarily treated with curative-intent surgery, and received subsequent adjuvant treatment, if indicated.

Results

The most frequently mutated genes were TP53 and NOTCH1. Other mutated genes included NOTCH3 and CDKN2A, among others. A significant number of mutations were private to dysplasia and invasive carcinoma, respectively, however, almost 20% were shared between them. Increasing genomic instability was observed when comparing histologically normal squamous mucosa with higher levels of dysplasia. High-grade dysplasia showed similarly rearranged genomes as invasive carcinoma. Pathways related to interferon alpha and gamma response were upregulated even in moderate dysplastic lesions with increasing expression in higher grades of dysplasia and carcinoma. SPINK5, a known tumor suppressor gene in HNSCC, was already downregulated in low-grade dysplastic lesions, indicating an early deactivation in the evolution of the disease.

Conclusion

Genomic alterations as well as aberrant immune gene expression can be observed early in the evolution of tumors of the upper aerodigestive tract, highlighting the potential for targeting early mechanisms of disease progression.

Gene-Expression Patterns of Tumor and Peritumor Tissues of Smoking and Non-Smoking HPV-Negative Patients with Head and Neck Squamous Cell Carcinoma

We studied the gene-expression patterns in specimens of tumor and peritumor tissue biopsies of 26 patients with head and neck carcinomas depending on smoking status. Histological and immunohistochemical examinations verified that all tumors belonged to the "classical" subgroup of head and neck carcinomas, and the HPV-negative tumor status was confirmed. The expression of 28 tumor-associated genes determined by RT-PCR was independent of patients' sex or age, TNM status, degree of differentiation, or tissue localization. Moreover, in peritumor tissue, none of the 28 genes were differentially expressed between the groups of smoking and nonsmoking patients. During oncotransformation in both studied groups, there were similar processes typical for HNSCC progression: the expression levels of paired keratins 4 and 13 were reduced, while the expression levels of keratin 17 and CD44 were significantly increased. However, further investigation revealed some distinctive features: the expression of the genes EGFR and TP63 increased significantly only in the nonsmoking group, and the expression of IL6, CDKN2A, EGF, and PITX1 genes changed only in the smoking group. In addition, correlation analysis identified several clusters within which genes displayed correlations in their expression levels. The largest group included 10 genes: TIMP1, TIMP2, WEE1, YAP, HIF1A, PI3KCA, UTP14A, APIP, PTEN, and SLC26A6. The genetic signatures associated with smoking habits that we have found may serve as a prerequisite for the development of diagnostic panels/tests predicting responses to different therapeutic strategies for HNSCC.

Anti-NOTCH1 therapy with OMP-52 M51 inhibits salivary adenoid cystic carcinoma by depressing epithelial-mesenchymal transition (EMT) process and inducing ferroptosis

Salivary adenoid cystic carcinoma (ACC) is a common type of salivary gland cancer, and the mechanisms underlying its progression still remain poorly understood without efficient therapies. NOTCH1, an evolutionally conserved cell-cell signaling pathway, is involved in the progression of ACC. In our study, we attempted to explore whether NOTCH1 suppression using the monoclonal anti-NOTCH1 antibody OMP-52 M51 could be of potential for ACC treatment. Here, we identified NOTCH1 elevation in human ACC tissues compared with the matched normal samples. Patients with metastasis expressed much higher NOTCH1. We then found that OMP-52 M51 markedly reduced the expression of NOTCH1 and its intracellular active form NICD1 (NOTCH1 intracellular domain). Importantly, OMP-52 M51 markedly reduced the proliferation, migration and invasion of ACC cells. RNA-Seq and in vitro studies further showed that OMP-52 M51 significantly induced ferroptosis in ACC cells, indicated by the increased cellular malondialdehyde (MDA), iron contents and lipid ROS production, and decreased glutathione (GSH) levels. Further, remarkable glutathione peroxidase 4 (GPX4) reduction was detected in ACC cells with OMP-52 M51 treatment. However, promoting NOTCH1 expression markedly abolished the function of OMP-52 M51 to induce ferroptosis. Intriguingly, low-dose OMP-52 M51 strongly facilitated the capacity of ferroptosis inducer erastin to trigger ferroptotic cell death, revealing that OMP-52 M51 could improve the sensitivity of ACC cells to ferroptosis. In vivo, OMP-52 M51 administration suppressed tumor growth and induced ferroptosis in the constructed ACC xenograft mouse model. Collectively, our findings demonstrated that NOTCH1 inhibition by OMP-52 M51 represses the proliferation and epithelial-mesenchymal transition (EMT) in ACCs, and promotes ferroptosis, revealing the potential therapeutical application of OMP-52 M51 in ACC.

Exploring the frontiers: tumor immune microenvironment and immunotherapy in head and neck squamous cell carcinoma

The global prevalence of head and neck malignancies positions them as the sixth most common form of cancer, with the head and neck squamous cell carcinoma (HNSCC) representing the predominant histological subtype. Despite advancements in multidisciplinary approaches and molecular targeted therapies, the therapeutic outcomes for HNSCC have only marginally improved, particularly in cases of recurrent or metastatic HNSCC (R/MHNSCC). This situation underscores the critical necessity for the development of innovative therapeutic strategies. Such strategies are essential not only to enhance the efficacy of HNSCC treatment but also to minimize the incidence of associated complications, thus improving overall patient prognosis. Cancer immunotherapy represents a cutting-edge cancer treatment that leverages the immune system for targeting and destroying cancer cells. It's applied to multiple cancers, including melanoma and lung cancer, offering precision, adaptability, and the potential for long-lasting remission through immune memory. It is observed that while HNSCC patients responsive to immunotherapy often experience prolonged therapeutic benefits, only a limited subset demonstrates such responsiveness. Additionally, significant clinical challenges remain, including the development of resistance to immunotherapy. The biological characteristics, dynamic inhibitory changes, and heterogeneity of the tumor microenvironment (TME) in HNSCC play critical roles in its pathogenesis, immune evasion, and therapeutic resistance. This review aims to elucidate the functions and mechanisms of anti-tumor immune cells and extracellular components within the HNSCC TME. It also introduces several immunosuppressive agents commonly utilized in HNSCC immunotherapy, examines factors influencing the effectiveness of these treatments, and provides a comprehensive summary of immunotherapeutic strategies relevant to HNSCC.

Regulation of the Notch signaling pathway by natural products for cancer therapy

The Notch signaling pathway is an evolutionarily conserved pathway that modulates normal biological processes involved in cellular differentiation, apoptosis, and stem cell self-renewal in a context-dependent fashion. Attributed to its pleiotropic physiological roles, both overexpression and silencing of the pathway are associated with the emergence, progression, and poorer prognosis in various types of cancer. To decrease disease incidence and promote survival, targeting Notch may have chemopreventive and anti-cancer effects. Natural products with profound historical origins have distinguished themselves from other therapies due to their easy access, high biological compatibility, low toxicity, and reliable effects at specific physiological sites in vivo. This review describes the Notch signaling pathway, particularly its normal activation process, and some main illnesses related to Notch signaling pathway dysregulation. Emphasis is placed on the effects and mechanisms of natural products targeting the Notch signaling pathway in diverse cancer types, including curcumin, ellagic acid (EA), resveratrol, genistein, epigallocatechin-3-gallate (EGCG), quercetin, and xanthohumol and so on. Existing evidence indicates that natural products are feasible solution to fight against cancer by targeting Notch signaling, either alone or in combination with current therapeutic agents.

Clinical implication of genetic intratumor heterogeneity for targeted therapy in head and neck cancer

BACKGROUND

Genomic profiling is increasingly used both in therapeutic decision-making and as inclusion criteria for trials testing targeted therapies. However, the mutational landscape may vary across different areas of a tumor and intratumor heterogeneity will challenge treatments or clinical decisions based on single tumor biopsies. The purpose of this study was to assess the clinical relevance of genetic intratumor heterogeneity in head and neck squamous cell carcinomas (HNSCC) using the ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT).

MATERIALS AND METHODS

This prospective study included 33 whole tumor specimens from 28 patients with primary or recurrent HNSCC referred for surgery. Three tumor blocks were selected from central, semi-peripheral, and peripheral positions, mimicking biopsies in three different locations. Genetic analysis of somatic copy number alterations (SCNAs) was performed on the three biopsies using Oncoscan, focusing on 45 preselected HNSCC genes of interest. Clinical relevance was assessed using the ESCAT score to investigate whether and how treatment decisions would change based on the three biopsies from the same tumor.

RESULTS

The SCNAs identified among 45 preselected genes within the three tumor biopsies derived from the same tumor revealed distinct variations. The detected discrepancies could potentially influence treatment approaches or clinical decisions in 36% of the patients if only one tumor biopsy was used. Recurrent tumors exhibited significantly higher variation in SCNAs than primary tumors (p = .024). No significant correlation between tumor size and heterogeneity (p = .7) was observed.

CONCLUSION

In 36% of patients diagnosed with HNSCC, clinically significant intratumor heterogeneity was observed which may have implications for patient management. This finding substantiates the need for future studies that specifically investigate the clinical implications associated with intratumor heterogeneity.

Optimization of a Three-Dimensional Culturing Method for Assessing the Impact of Cisplatin on Notch Signaling in Head and Neck Squamous Cell Carcinoma (HNSCC)

Head and neck squamous cell carcinoma (HNSCC) is a prevalent cancer type, with cisplatin being a primary treatment approach. However, drug resistance and therapy failure pose a significant challenge, affecting nearly 50% of patients over time. This research had two aims: (1) to optimize a 3D cell-culture method for assessing the interplay between tumor cells and cancer-associated fibroblasts (CAFs) in vitro; and (2) to study how cisplatin impacts the Notch pathway, particularly considering the role of CAFs. Using our optimized "3D sheet model" approach, we tested two HNSCC cell lines with different cisplatin sensitivities and moderate, non-mutated NOTCH1 and -3 expressions. Combining cisplatin with a γ-secretase inhibitor (crenigacestat) increased sensitivity and induced cell death in the less sensitive cell line, while cisplatin alone was more effective in the moderately sensitive line and sensitivity decreased with the Notch inhibitor. Cisplatin boosted the expression of core Notch signaling proteins in 3D monocultures of both lines, which was counteracted by crenigacestat. In contrast, the presence of patient-derived CAFs mitigated effects and protected both cell lines from cisplatin toxicity. Elevated NOTCH1 and NOTCH3 protein levels were consistently correlated with reduced cisplatin sensitivity and increased cell survival. Additionally, the Notch ligand JAG2 had additional, protective effects reducing cell death from cisplatin exposure. In summary, we observed an inverse relationship between NOTCH1 and NOTCH3 levels and cisplatin responsiveness, overall protective effects by CAFs, and a potential link between JAG2 expression with tumor cell survival.

NOTCH1 and PIK3CA mutation are related to HPV-associated vulvar squamous cell carcinoma

NOTCH1 and PIK3CA are members of important cell signalling pathways that are deregulated in squamous cell carcinomas of various organs. Vulvar squamous cell carcinomas (vulvSCC) are classically divided into two pathways, HPV-associated or HPV-independent, but the effect of NOTCH1 and PIK3CA mutations in both groups is unclear. We analysed two different cohorts of vulvSCC using Hybrid Capture-based Comprehensive Genomic Profiling and identified NOTCH1 and PIK3CA mutations in 35% and 31% of 48 primary vulvSCC. In this first cohort, PIK3CA and NOTCH1 mutations were significantly correlated with HPV infection (p < 0.01). Furthermore, mutations in both genes were associated with an advanced tumor stage and poorly differentiated status (p < 0.05). PIK3CA and NOTCH1 mutations were also associated with shorter patient survival which did not reach significance. In the second cohort of 735 advanced vulvSCC from metastatic site biopsies or from sites of unresectable loco-regional disease, NOTCH1 and PIK3CA mutations were reported in 14% and 20.3%, respectively. 4 of 48 (8%) and 22 of 735 vulvSCC (3.0%) featured genomic alterations (short variants and/or copy number changes and/or rearrangements) in both NOTCH1 and PIK3CA. NOTCH1 mutations were mostly located in the extracellular EGF-like domains, were inactivating and indicated that NOTCH1 functions predominantly as a tumor suppressor gene in vulvSCC. In contrast, PIK3CA mutations favored hotspot codons 1624 and 1633 of the gene, indicating that PIK3CA acts as an oncogene in vulvar carcinogenesis. In conclusion, NOTCH1 and PIK3CA mutations are detectable in a substantial proportion of vulvSCC and are related to HPV infection and more aggressive tumor behaviour.

Increased NOTCH1 expression is associated with low survival in moderate/ poor differentiated human oral squamous cell carcinoma patients

Notch deregulation has been reported in various types of cancers, including Oral squamous cell carcinomas (OSCCs). The role of Notch1 signaling in oral squamous cell carcinoma (OSCC) remains poorly understood. In this study, NOTCH1 was aberrantly expressed in human oral cancer tissues compared with that in normal marginal tissues and was associated with poor prognosis. The positive Notch 1 expression was significantly associated with poor tumor differentiation status. Kaplan-Meier survival curves revealed that elevated cytoplasmic NOTCH1 expression levels in OSCC patients were associated with poor overall survival. Moreover, multivariate COX proportional hazard models revealed that T N status, AJCC stage histological grade were independent prognostic factors for survival. Our result clearly demonstrates the oncogenic role of Notch1 in oral cancer and Notch1 may be a useful biomarker to target oral cancer patients.

Modulation of Notch Signaling by Small-Molecular Compounds and Its Potential in Anticancer Studies

Notch signaling is responsible for conveying messages between cells through direct contact, playing a pivotal role in tissue development and homeostasis. The modulation of Notch-related processes, such as cell growth, differentiation, viability, and cell fate, offer opportunities to better understand and prevent disease progression, including cancer. Currently, research efforts are mainly focused on attempts to inhibit Notch signaling in tumors with strong oncogenic, gain-of-function (GoF) or hyperactivation of Notch signaling. The goal is to reduce the growth and proliferation of cancer cells, interfere with neo-angiogenesis, increase chemosensitivity, potentially target cancer stem cells, tumor dormancy, and invasion, and induce apoptosis. Attempts to pharmacologically enhance or restore disturbed Notch signaling for anticancer therapies are less frequent. However, in some cancer types, such as squamous cell carcinomas, preferentially, loss-of-function (LoF) mutations have been confirmed, and restoring but not blocking Notch functions may be beneficial for therapy. The modulation of Notch signaling can be performed at several key levels related to NOTCH receptor expression, translation, posttranslational (proteolytic) processing, glycosylation, transport, and activation. This further includes blocking the interaction with Notch-related nuclear DNA transcription. Examples of small-molecular chemical compounds, that modulate individual elements of Notch signaling at the mentioned levels, have been described in the recent literature.

Evaluation of the anticancer activity of RIN-1, a Notch signaling modulator, in head and neck squamous cell carcinoma

Notch signalling is one of the key molecular pathways involved in cell-to-cell signal transduction. Although the mechanisms of action of the NOTCH receptors are already relatively well known, their biological implications remain unclear, especially during the initiation and progression of head and neck squamous cell carcinoma (HNSCC). Here, we present the growth- and differentiation-modulating effects of various "next generation" small molecule Notch modulators represented by RIN-1, and CB-103, on HNSCC, compared to gamma secretase inhibitors as "conventional" NOTCH interfering compounds, like DAPT. These molecules were tested in different cell- and tissue culture conditions represented by 2D monolayer, non-adherent or spheroid culture, 3D organoid cultures, and zebrafish in vivo model. The most pronounced, pleiotropic effects were observed for the NOTCH modulator RIN-1. At the molecular level, RIN-1-dependent activation of Notch signalling led to characteristic changes in the expression of NOTCH-regulated targets, i.e., the transcriptional suppressors HES1 and HEY1, p21 (CDKN1A) cell cycle inhibitor, and pro-apoptotic BAX markers. These changes led to restriction of proliferation, growth, and reduced motility of HNSCC cells in 2D cultures. Consequently, cell cycle arrest in the G2-M phase and induction of apoptosis were observed. Similar anticancer effects were observed in 3D cultures and in the zebrafish model. In contrast, RIN-1 treatment resulted in inhibition of Notch signalling and the growth of HNSCC spheroids under non-adherent cell culture conditions. Our results suggest that modulation of Notch signalling could be used as a chemotherapeutic agent in selected patients with intact NOTCH signaling.

The Distinctive Features behind the Aggressiveness of Oral and Cutaneous Squamous Cell Carcinomas

Squamous cell carcinomas arise from stratified squamous epithelia. Here, a comparative analysis based on recent studies defining the genetic alterations and composition of the stroma of oral and cutaneous squamous cell carcinomas (OSCC and CSCC, respectively) was performed. Both carcinomas share some but not all histological and genetic features. This review was focused on how mutations in tumor suppressor genes and protooncogenes cooperate to determine the differentiation, aggressiveness, and metastatic potential of OSCC and CSCC. In fact, driver mutations in tumor suppressor genes are more frequently observed in OSCC than CSCC. These include mutations in TP53 (encoding pP53 protein), CDKN2A (encoding cyclin dependent kinase inhibitor 2A), FAT1 (encoding FAT atypical cadherin 1), and KMT2D (encoding lysine methyltransferase 2D), with the exception of NOTCH (encoding Notch receptor 1), whose mutation frequency is lower in OSCC compared to CSCC. Finally, we describe the differential composition of the tumor microenvironment and how this influences the aggressiveness of each tumor type. Although both OSCC and CSCC tumors are highly infiltrated by immune cells, high levels of tumor-infiltrating lymphocytes (TILs) have been more frequently reported as predictors of better outcomes in OSCC than CSCC. In conclusion, OSCC and CSCC partially share genetic alterations and possess different causal factors triggering their development. The tumor microenvironment plays a key role determining the outcome of the disease.

Exosome-mediated long noncoding RNA (lncRNA) PART1 suppresses malignant progression of oral squamous cell carcinoma via miR-17-5p/SOCS6 axis

BACKGROUND

Exosomes derived from oral squamous cell carcinoma (OSCC) could modulate OSCC development. This study aimed to explore effects of exosome-mediated lncRNA PART1 on OSCC cells.

METHODS

This study was performed in Tianjin Medical University Cancer Institute from February 2021 to March 2022. Bioinformatic analysis was performed on the public database GEPIA (http://gepia.cancer-pku.cn/). Exosomes isolated from cell lines squamous cell carcinoma 9 (SCC9) and Centre Antoine Lacassagne-27 (CAL27) were identified by transmission electron microscope and western blot. Exosome-mediated lncRNA PART1, microRNA-17-5p(miR-17-5p) and suppressor of cytokine signaling 6(SOCS6) RNA expressions were assessed by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Cell counting kit8(CCK-8), caspase-3 activity, and flow cytometry were applied to evaluate OSCC cell viabilities and apoptosis. Meanwhile, OSCC cell migratory ability and invasiveness were evaluated using transwell assay. Bindings between miR-17-5p and lncRNA PART1 or SOCS6 were validated using the luciferase reporter test. Western blot was used for detecting the protein levels of SOCS6, phosphorylated signal transducer and activator of transcription 3 (STAT3) and STAT3.

RESULTS

: According to GEPIA, lncRNA PART1 was downregulated in OSCC tissue samples and cells, and it had a positive correlation with the good prognosis of Head and neck squamous cell cancer (HNSCC) patients. After the exosomes from OSCC cells were isolated and verified, PART1 was then confirmed to be secreted by exosomes. Further, overexpression of exosome-mediated lncRNA PART1 inhibited OSCC cell viabilities, migration, and invasiveness but facilitated OSCC cell apoptosis. PART1 upregulated SOCS6 through sponging miR-17-5p. Moreover, exosome-mediated lncRNA PART1 suppressed the phosphorylation of STAT3.

DISCUSSION

Exosome-mediated lncRNA PART1 could mediate the OSCC progression via miR-17-5p/SOCS6 axis in vitro, suggesting that lncRNA PART1 might be a target for treating OSCC.

NOTCH pathway inactivation reprograms stem-like oral cancer cells to JAK-STAT dependent state and provides the opportunity of synthetic lethality

BACKGROUND

We have recently provided the evidence of interconvertible cellular states, driving non-genetic heterogeneity among stem-like oral cancer cells (oral-SLCCs). Here, NOTCH pathway-activity status is explored as one of the possible mechanisms behind this stochastic plasticity.

METHODS

Oral-SLCCs were enriched in 3D-spheroids. Constitutively-active and inactive status of NOTCH pathway was achieved by genetic or pharmacological approaches. RNA sequencing and real-time PCR was performed for gene expression studies. in vitro cytotoxicity assessments were performed by AlamarBlue assay and in vivo effects were studied by xenograft growth in zebrafish embryo.

RESULTS

We have observed stochastic plasticity in oral-SLCCs, spontaneously maintaining both NOTCH-active and inactive states. While cisplatin refraction was associated with post-treatment adaptation to the active-state of NOTCH pathway, oral-SLCCs with inactive NOTCH pathway status showed aggressive tumor growth and poor prognosis. RNAseq analysis clearly suggested the upregulation of JAK-STAT pathway in NOTCH pathway-inactive subset. The 3D-spheroids with lower NOTCH-activity status displayed significantly higher sensitivity to JAK-selective drugs, Ruxolitinib or Tofacitinib or siRNA mediated downregulation of tested partners STAT3/4. Oral-SLCCs were programmed to adapt the inactive status of NOTCH pathway by exposing to γ-secretase inhibitors, LY411575 or RO4929097, followed by targeting with JAK-inhibitors, Ruxolitinib or Tofacitinib. This approach resulted in a very significant inhibition in viability of 3D-spheroids as well as xenograft initiation in Zebrafish embryos.

CONCLUSION

Study revealed for the first time that NOTCH pathway-inactive state exhibit activation of JAK-STAT pathways, as synthetic lethal pair. Therefore, co-inhibition of these pathway may serve as novel therapeutic strategy against aggressive oral cancer.

Circulating Tumor DNA in Head and Neck Squamous Cell Carcinoma

Tumors shed cell-free DNA (cfDNA) into the plasma. "Liquid biopsies" are a diagnostic test to analyze cfDNA in order to detect minimal residual cancer, profile the genomic tumor landscape, and monitor cancers non-invasively over time. This technique may be useful in patients with head and neck squamous cell carcinoma (HNSCC) due to genetic tumor heterogeneity and limitations in imaging sensitivity. However, there are technical challenges that need to be overcome for the widespread use of liquid biopsy in the clinical management of these patients. In this review, we discuss our current understanding of HNSCC genetics and the role of cfDNA genomic analyses as an emerging precision diagnostic tool.

A NOTCH1 Mutation Found in a Newly Established Ovarian Cancer Cell Line (FDOVL) Promotes Lymph Node Metastasis in Ovarian Cancer

Peritoneal implantation and lymph node metastasis have different driving mechanisms in ovarian cancer. Elucidating the underlying mechanism of lymph node metastasis is important for treatment outcomes. A new cell line, FDOVL, was established from a metastatic lymph node of a patient with primary platinum-resistant ovarian cancer and was then characterized. The effect of NOTCH1-p.C702fs mutation and NOTCH1 inhibitor on migration was evaluated in vitro and in vivo. Ten paired primary sites and metastatic lymph nodes were analyzed by RNA sequencing. The FDOVL cell line with serious karyotype abnormalities could be stably passaged and could be used to generated xenografts. NOTCH1-p.C702fs mutation was found exclusively in the FDOVL cell line and the metastatic lymph node. The mutation promoted migration and invasion in cell and animal models, and these effects were markedly repressed by the NOTCH inhibitor LY3039478. RNA sequencing confirmed CSF3 as the downstream effector of NOTCH1 mutation. Furthermore, the mutation was significantly more common in metastatic lymph nodes than in other peritoneal metastases in 10 paired samples (60% vs. 20%). The study revealed that NOTCH1 mutation is probably a driver of lymph node metastasis in ovarian cancer, which offers new ideas for the treatment of ovarian cancer lymph node metastasis with NOTCH inhibitors.

Targeted therapy for head and neck cancer: signaling pathways and clinical studies

Head and neck cancer (HNC) is malignant, genetically complex and difficult to treat and is the sixth most frequent cancer, with tobacco, alcohol and human papillomavirus being major risk factors. Based on epigenetic data, HNC is remarkably heterogeneous, and treatment remains challenging. There is a lack of significant improvement in survival and quality of life in patients with HNC. Over half of HNC patients experience locoregional recurrence or distal metastasis despite the current multiple traditional therapeutic strategies and immunotherapy. In addition, resistance to chemotherapy, radiotherapy and some targeted therapies is common. Therefore, it is urgent to explore more effective and tolerable targeted therapies to improve the clinical outcomes of HNC patients. Recent targeted therapy studies have focused on identifying promising biomarkers and developing more effective targeted therapies. A well understanding of the pathogenesis of HNC contributes to learning more about its inner association, which provides novel insight into the development of small molecule inhibitors. In this review, we summarized the vital signaling pathways and discussed the current potential therapeutic targets against critical molecules in HNC, as well as presenting preclinical animal models and ongoing or completed clinical studies about targeted therapy, which may contribute to a more favorable prognosis of HNC. Targeted therapy in combination with other therapies and its limitations were also discussed.

Notch1 Protects against Ischemic-Reperfusion Injury by Suppressing PTEN-Pink1-Mediated Mitochondrial Dysfunction and Mitophagy

BACKGROUND

Myocardial ischemia/reperfusion injury is associated with adverse cardiovascular outcomes after acute myocardial infarction. However, the molecular mechanism of ischemia/reperfusion injury remains unclear. Mitochondria dysfunction is a participant in and regulator of myocardial ischemia-reperfusion injury. However, the molecular mechanisms involved in this process are not yet fully understood. We previously reported that Notch1 can reduce mitochondrial lysis, reduce myocardial infarct size, and inhibit ventricular remodeling. Herein, we explore the role of the downstream target Notch1 in mitochondrial regulation.

METHODS

This study constructs an ischemic/reperfusion injury rat model and a hypoxia/reoxygenation cell model. The expression of PTEN is detected by real-time PCR, Western blot, and immunofluorescence staining. Cell viability is analyzed with CCK-8. Apoptosis level is detected via the TUNEL assay, and mitochondrial fission/fusion is analyzed with MitoTracker Green staining. Cardiac troponin I (cTnI), lactate dehydrogenase (LDH), superoxide dismutase (SOD), and CK levels of creatine kinase-MB (CK) are measured with ELISA kits.

RESULTS

We found that PETN-Pink1-Parkin signaling is inhibited by Notch1 I/R in injured neonatal cardiomyocytes and hearts, i.e., via the inhibition of mitochondrial dysfunction and fragmentation. With the recure of PTEN or Pink1, the protective effect of Notch1 was largely diminished.

CONCLUSION

These results suggest that N1ICD acts protectively against ischemic reperfusion injury by suppressing PTEN-Pink1-mediated mitochondrial dysfunction and fragmentation.

Sustained Aurora Kinase B Expression Confers Resistance to PI3K Inhibition in Head and Neck Squamous Cell Carcinoma

Tumor suppressor mutations in head and neck squamous cell carcinoma (HNSCC) dominate the genomic landscape, hindering the development of effective targeted therapies. Truncating and missense mutations in NOTCH1 are frequent in HNSCC, and inhibition of PI3K can selectively target NOTCH1 mutant (NOTCH1MUT) HNSCC cells. In this study, we identify several proteins that are differentially regulated in HNSCC cells after PI3K inhibition based on NOTCH1MUT status. Expression of Aurora kinase B (Aurora B), AKT, and PDK1 following PI3K inhibition was significantly lower in NOTCH1MUT cell lines than in wild-type NOTCH1 (NOTCH1WT) cells or NOTCH1MUT cells with acquired resistance to PI3K inhibition. Combined inhibition of PI3K and Aurora B was synergistic, enhancing apoptosis in vitro and leading to durable tumor regression in vivo. Overexpression of Aurora B in NOTCH1MUT HNSCC cells led to resistance to PI3K inhibition, while Aurora B knockdown increased sensitivity of NOTCH1WT cells. In addition, overexpression of Aurora B in NOTCH1MUT HNSCC cells increased total protein levels of AKT and PDK1. AKT depletion in NOTCH1WT cells and overexpression in NOTCH1MUT cells similarly altered sensitivity to PI3K inhibition, and manipulation of AKT levels affected PDK1 but not Aurora B levels. These data define a novel pathway in which Aurora B upregulates AKT that subsequently increases PDK1 selectively in NOTCH1MUT cells to mediate HNSCC survival in response to PI3K inhibition. These findings may lead to an effective therapeutic approach for HNSCC with NOTCH1MUT while sparing normal cells.

SIGNIFICANCE

Aurora B signaling facilitates resistance to PI3K inhibition in head and neck squamous cell carcinoma, suggesting that combined inhibition of PI3K and Aurora kinase is a rational therapeutic strategy to overcome resistance.

Genomic and Immune Approach in Platinum Refractory HPV-Negative Head and Neck Squamous Cell Carcinoma Patients Treated with Immunotherapy: A Novel Combined Profile

Introduction: Only a minority of patients with platinum refractory head and neck squamous cell carcinoma (PR/HNSCC) gain some lasting benefit from immunotherapy. Methods: The combined role of the comprehensive genomic (through the FoundationOne Cdx test) and immune profiles of 10 PR/HNSCC patients treated with the anti-PD-1 nivolumab was evaluated. The immune profiles were studied both at baseline and at the second cycle of immunotherapy, weighing 20 circulating cytokines/chemokines, adhesion molecules, and 14 soluble immune checkpoints dosed through a multiplex assay. A connectivity map was obtained by calculating the Spearman correlation between the expression profiles of circulating molecules. Results: Early progression occurred in five patients, each of them showing TP53 alteration and three of them showing a mutation/loss/amplification of genes involved in the cyclin-dependent kinase pathway. In addition, ERB2 amplification (1 patient), BRCA1 mutation (1 patient), and NOTCH1 genes alteration (3 patients) occurred. Five patients achieved either stable disease or partial response. Four of them carried mutations in PI3K/AKT/PTEN pathways. In the only two patients, with a long response to immunotherapy, the tumor mutational burden (TMB) was high. Moreover, a distinct signature, in terms of network connectivity of the circulating soluble molecules, characterizing responder and non-responder patients, was evidenced. Moreover, a strong negative and statistically significant (p-value ≤ 0.05) correlation with alive status was evidenced for sE-selectin at T1. Conclusions: Our results highlighted the complexity and heterogeneity of HNSCCs, even though it was in a small cohort. Molecular and immune approaches, combined in a single profile, could represent a promising strategy, in the context of precision immunotherapy.

The role of T-cells in head and neck squamous cell carcinoma: From immunity to immunotherapy

Head and neck squamous cell carcinoma (HNSCC) encompass a group of complex entities of tumours affecting the aerodigestive upper tract. The main risk factors are strongly related to tobacco and alcohol consumption, but also HPV infection is often associated. Surgery, radiotherapy and/or chemotherapy are the standard treatments, though the 5-year overall survival is less than 50%. The advances in genomics, molecular medicine, immunology, and nanotechnology have shed a light on tumour biology which helps clinical researchers to obtain more efficacious and less toxic therapies. Head and neck tumours possess different immune escape mechanisms including diminishing the immune response through modulating immune checkpoints, in addition to the recruitment and differentiation of suppressive immune cells. The insights into the HNSCC biology and its strong interaction with the tumour microenvironment highlights the role of immunomodulating agents. Recently, the knowledge of the immunological features of these tumours has paved the way for the discovery of effective biomarkers that allow a better selection of patients with odds of improving overall survival through immunotherapy. Specially biomarkers regarding immune checkpoint inhibitors antibodies, such as anti-PD-1/PD-L1 and anti-CTLA-4 in combination with standard therapy or as monotherapy. New immunotherapies to treat head and neck cancer carcinomas, such as CAR T cells and nanoparticles have been the center of attention and in this review, we discuss the necessity of finding targets for the T cell in the cancer cells to generate CAR T cells, but also the relevance of evaluating specificity and safety of those therapies.

Inhibition of the Phosphatidylinositol-3 Kinase Pathway Using Bimiralisib in Loss-of-Function NOTCH1-Mutant Head and Neck Cancer

BACKGROUND

PI3K/mTOR inhibition leads to apoptosis of NOTCH1-mutant head and neck squamous cell carcinoma (HNSCC) cells. We tested the efficacy of the PI3K/mTOR inhibitor bimiralisib in patients with NOTCH1-mutant HNSCC.

METHODS

Patients with recurrent/metastatic NOTCH1-mutant HNSCC who had progressed during chemotherapy and immunotherapy received bimiralisib until unacceptable toxicity or progression. To assess whether NOTCH1 mutations can be detected in blood, we measured circulating tumor DNA (ctDNA). To assess activated NOTCH1 protein levels, we quantitated cleaved NOTCH1 (cl-NOTCH) by immunohistochemistry.

RESULTS

Eight patients were treated, and 6 were evaluable for response. The objective response rate was 17%. For all 8 patients, median progression-free and overall survival was 5 and 7 months, respectively. Bimiralisib was well tolerated, with expected hyperglycemia. Pharmacokinetic values were consistent with published studies. NOTCH1 mutations were detected in 83.3% of ctDNA. Staining for tumor cl-NOTCH1 was negative. The trial closed early due to sponsor insolvency.

CONCLUSION

Although the trial was small, outcomes with bimiralisib were better than the historical standard of care; Results will need to be confirmed in a larger trial. The lack of cl-NOTCH1 was consistent with loss-of-function mutations and validated our mutation function algorithm. The ability to detect NOTCH1 mutations in blood will help future studies. (ClinicalTrials.gov Identifier: NCT03740100).

Novel Systemic Treatment Modalities Including Immunotherapy and Molecular Targeted Therapy for Recurrent and Metastatic Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinomas (HNSCCs) are the sixth most common cancers worldwide. More than half of patients with HNSCC eventually experience disease recurrence and/or metastasis, which can threaten their long-term survival. HNSCCs located in the oral cavity and larynx are usually associated with tobacco and/or alcohol use, whereas human papillomavirus (HPV) infection, particularly HPV16 infection, is increasingly recognized as a cause of oropharyngeal HNSCC. Despite clinical, histologic, and molecular differences between HPV-positive and HPV-negative HNSCCs, current treatment approaches are the same. For recurrent disease, these strategies include chemotherapy, immunotherapy with PD-1-inhibitors, or a monoclonal antibody, cetuximab, that targets epidermal growth factor; these therapies can be administered either as single agents or in combination. However, these treatment strategies carry a high risk of toxic side effects; therefore, more effective and less toxic treatments are needed. The landscape of HNSCC therapy is changing significantly; numerous clinical trials are underway to test novel therapeutic options like adaptive cellular therapy, antibody-drug conjugates, new targeted therapy agents, novel immunotherapy combinations, and therapeutic vaccines. This review helps in understanding the various developments in HNSCC therapy and sheds light on the path ahead in terms of further research in this field.

NOTCH1 mutation associates with impaired immune response and decreased relapse-free survival in patients with resected T1-2N0 laryngeal cancer

Background

Patients with early-stage laryngeal cancer, even stage T1-2N0, are at considerable risk of recurrence and death. The genetic and immunologic characteristics of recurrent laryngeal cancer remain unclear.

Methods

A total of 52 T1-2N0 laryngeal cancer patients were enrolled. Of these, 42 tissue samples were performed by targeted DNA sequencing, and 21 cases were performed by NanoString immuno-oncology targeted RNA sequencing to identify the distinct molecular bases and immunologic features associated with relapse in patients with early laryngeal cancer, respectively.

Results

To the best to our knowledge, we present for the first time an overview of the genomic mutation spectrum of early-stage laryngeal cancers. A total of 469 genomic alterations were detected in 211 distinct cancer-relevant genes, and the genes found to be mutated in more than five patients (>10%) included tumor protein p53 (TP53, 78.5%), FAT atypical cadherin 1 (FAT1, 26%), LDL receptor related protein 1B (LRP1B, 19%), cyclin dependent kinase inhibitor 2A (CDKN2A, 17%), tet methylcytosine dioxygenase 2 (TET2, 17%), notch receptor 1 (NOTCH1, 12%) and neuregulin 1 (NRG1, 12%). Recurrent laryngeal cancer demonstrated a higher tumor mutation burden (TMB), as well as higher LRP1B mutation and NOTCH1 mutation rates. Univariate and multivariate analyses revealed that high TMB (TMB-H) and NOTCH1 mutation are independent genetic factors that are significantly associated with shorter relapse-free survival (RFS). Simultaneously, the results of the transcriptome analysis presented recurrent tumors with NOTCH1 mutation displayed upregulation of the cell cycle pathway, along with decreased B cells score, T cells score, immune signature score and tumor-infiltrating lymphocytes (TILs) score. The Cancer Genome Atlas (TCGA)-laryngeal cancer dataset also revealed weakened immune response and impaired adhesion functions in NOTCH1-mutant patients.

Conclusions

Genomic instability and impaired immune response are key features of the immunosurveillance escape and recurrence of early laryngeal cancer after surgery. These findings revealed immunophenotypic attenuation in recurrent tumors and provided valuable information for improving the management of these high-risk patients. Due to the small number of patients in this study, these differences need to be further validated in a larger cohort.

Topical Bimiralisib Shows Meaningful Cutaneous Drug Levels in Healthy Volunteers and Mycosis Fungoides Patients but No Clinical Activity in a First-in-Human, Randomized Controlled Trial

Mycosis fungoides (MF) is a subtype of CTCL with a low incidence and high medical need for novel treatments. The objective of this randomized, placebo-controlled, double-blinded, first-in-human study was to evaluate safety, efficacy, cutaneous and systemic pharmacokinetics (PK) of topical bimiralisib in healthy volunteers (HVs) and MF patients. In this trial, a total of 6 HVs and 19 early-stage MF patients were treated with 2.0% bimiralisib gel and/or placebo. Drug efficacy was assessed by the Composite Assessment of Index Lesion Severity (CAILS) score, supported by objective measuring methods to quantify lesion severity. PK blood samples were collected frequently and cutaneous PK was investigated in skin punch biopsies on the last day of treatment. Local distribution of bimiralisib in HVs showed a mean exposure of 2.54 µg/g in the epidermis. A systemic concentration was observed after application of a target dose of 2 mg/cm2 on 400 cm2, with a mean Cavg of 0.96 ng/mL. Systemic exposure of bimiralisib was reached in all treated MF patients, and normalized plasma concentrations showed a 144% increased exposure compared to HVs, with an observed mean Cavg of 4.49 ng/mL and a mean cutaneous concentration of 5.3 µg/g. No difference in CAILS or objective lesion severity quantification upon 42 days of once-daily treatment was observed in the MF patient group. In general, the treatment was well tolerated in terms of local reactions as well as systemic adverse events. In conclusion, we showed that topical bimiralisib treatment leads to (i) meaningful cutaneous drug levels and (ii) well-tolerated systemic drug exposure in MF patients and (iii) a lack of clinical efficacy, in need of further exploration due to numerous unknown factors, before depreciation of topical bimiralisib as a novel therapeutic drug for CTCLs.

NOTCH1 Intracellular Domain and the Tumor Microenvironment as Prognostic Markers in HNSCC

Simple Summary

In the head and neck, a large proportion of squamous cell carcinoma demonstrate a mutation of the NOTCH1 gene. The aim of this project was to investigate the role of NOTCH1 and immunological characteristics and highlight a potential rationale for therapy. We found that a high expression of NOTCH1 intracellular domain in these patients is associated with reduced overall survival. In vitro experiments additionally showed a reduction of migration and proliferation of cancer cells when NOTCH1 was knocked down. NOTCH1 is, therefore, most likely involved in migration and proliferation of head and neck squamous cell carcinoma and is a prognostic marker in these patients.

Abstract

(1) Background: NOTCH1 is the second most common mutated gene in whole-exome sequencing of HNSCC. The aim of this project was to gain further insight into the relevance of NOTCH1 in HNSCC, potentially establishing NOTCH1 as a prognostic marker or therapeutic target; (2) Methods: NOTCH1 was silenced via RNA interference in six HNSCC cell lines and the impact was evaluated in migration and proliferation assays. Subsequently, the protein expression of NOTCH1 intracellular domain (NICD) and NOTCH1 mRNA expression were examined in 70 oropharyngeal squamous cell cancer tissue samples. Lastly, the NICD expression was compared with the local infiltration of lymphocytes, measured with the immunoscore; (3) Results: Knockdown of NOTCH1 decreased migration and proliferation. A high NICD expression was associated with lower OS. A high immunoscore resulted in significantly better OS. NICD expression was independent of the immunoscore and as a whole differentiated three distinct prognostic groups; (4) Conclusions: These data suggest that NOTCH1 is involved in migration and proliferation of HNSCC cell lines. In vivo, NICD expression was associated with overall survival and could, therefore, be used as a prognostic marker. NICD expression differs from NOTCH1 mRNA levels, potentially explaining the previously suggested bimodal role as an oncogene and tumor suppressor in HNSCC.

The Antitumoral Effect of Paris Saponin II on Head and Neck Squamous Cell Carcinomas Mediated via the Nitric Oxide Metabolic Pathway

Paris saponin has shown great therapeutic value in cancer therapy. We used isolated Paris saponin II (PSII), an active component of Paris saponin, and demonstrated its antitumor effect on human head and neck squamous cell carcinoma cell lines. Additionally, we investigated its mechanisms of action in vivo by establishing a xenograft mouse model. The results showed that PSII had presented strong anticancer effects on both hypopharyngeal malignant tumor cell lines (FaDu) and laryngeal carcinoma cell lines (Tu212 and Tu686). In addition, we successfully isolated and cultured the head and neck squamous stem cells and the primary fibroblasts to perform metabonomics studies. The results showed that RPII remarkably decreased energy metabolism, and type III nitric oxide synthase 3 (NOS3) may be a target to block tumor growth. Furthermore, we found that PSII inhibited HNSCC proliferation and metastasis by inhibiting the nitric oxide metabolic pathway. Overall, these results demonstrated that PSII is a potent anticancer agent, and the metabonomics analysis is a valuable tool to investigate and establish the antitumor effects of traditional Chinese medicines.

Pathogenesis of Penile Squamous Cell Carcinoma: Molecular Update and Systematic Review

Penile squamous cell carcinoma (PSCC) is a rare but aggressive neoplasm with dual pathogenesis (human papillomavirus (HPV)-associated and HPV-independent). The development of targeted treatment is hindered by poor knowledge of the molecular landscape of PSCC. We performed a thorough review of genetic alterations of PSCC focused on somatic mutations and/or copy number alterations. A total of seven articles have been identified which, overall, include 268 PSCC. However, the series are heterogeneous regarding methodologies employed for DNA sequencing and HPV detection together with HPV prevalence, and include, in general, a limited number of cases, which results in markedly different findings. Reported top-ranked mutations involve TP53, CDKN2A, FAT1, NOTCH-1 and PIK3CA. Numerical alterations involve gains in MYC and EGFR, as well as amplifications in HPV integration loci. A few genes including TP53, CDKN2A, PIK3CA and CCND1 harbor both somatic mutations and copy number alterations. Notch, RTK-RAS and Hippo pathways are frequently deregulated. Nevertheless, the relevance of the identified alterations, their role in signaling pathways or their association with HPV status remain elusive. Combined targeting of different pathways might represent a valid therapeutic approach in PSCC. This work calls for large-scale sequencing studies with robust HPV testing to improve the genomic understanding of PSCC.

Shooting at Moving and Hidden Targets-Tumour Cell Plasticity and the Notch Signalling Pathway in Head and Neck Squamous Cell Carcinomas

Head and Neck Squamous Cell Carcinoma (HNSCC) is often aggressive, with poor response to current therapies in approximately 40-50% of the patients. Current therapies are restricted to operation and irradiation, often combined with a small number of standard-of-care chemotherapeutic drugs, preferentially for advanced tumour patients. Only very recently, newer targeted therapies have entered the clinics, including Cetuximab, which targets the EGF receptor (EGFR), and several immune checkpoint inhibitors targeting the immune receptor PD-1 and its ligand PD-L1. HNSCC tumour tissues are characterized by a high degree of intra-tumour heterogeneity (ITH), and non-genetic alterations that may affect both non-transformed cells, such as cancer-associated fibroblasts (CAFs), and transformed carcinoma cells. This very high degree of heterogeneity likely contributes to acquired drug resistance, tumour dormancy, relapse, and distant or lymph node metastasis. ITH, in turn, is likely promoted by pronounced tumour cell plasticity, which manifests in highly dynamic and reversible phenomena such as of partial or hybrid forms of epithelial-to-mesenchymal transition (EMT), and enhanced tumour stemness. Stemness and tumour cell plasticity are strongly promoted by Notch signalling, which remains poorly understood especially in HNSCC. Here, we aim to elucidate how Notch signal may act both as a tumour suppressor and proto-oncogenic, probably during different stages of tumour cell initiation and progression. Notch signalling also interacts with numerous other signalling pathways, that may also have a decisive impact on tumour cell plasticity, acquired radio/chemoresistance, and metastatic progression of HNSCC. We outline the current stage of research related to Notch signalling, and how this pathway may be intricately interconnected with other, druggable targets and signalling mechanisms in HNSCC.

Sesamol induces cytotoxicity via mitochondrial apoptosis in SCC-25 cells

Sesamol is the main constituent of sesame seed oil and is obtained from Sesamum indicum. Oral squamous cell carcinoma (OSCC) is one of the most common neoplasms affecting the oral cavity. In this study, we investigated the cytotoxic potentials of sesamol on human oral squamous carcinoma (SCC-25) cells. Human oral squamous carcinoma cells were treated with different concentrations (62.5, 125, and 250 μM/mL) of sesamol for 24 h. Cytotoxicity was analyzed by 3- (4, 5- dimethylthiazol -2- yl) -2, 5-diphenyltetrazolium bromide (MTT) assay. Intracellular reactive oxygen species (ROS) expression was investigated by dichloro-dihydro-fluorescein diacetate assay. Apoptosis-related morphology was analyzed by acridine orange/ethidium bromide staining. Caspase-9 expression was analyzed by confocal microscopic double immunofluorescence staining. Mitochondrial apoptosis-related markers are analyzed using qPCR. Sesamol treatment caused a significant cytotoxic effect in OSCC cells. Sesamol-induced cytotoxic effect was associated with intracellular ROS generation. Sesamol treatments induced a significant increase in the early and late apoptotic cells. This treatment also induced caspase-9 expression in OSCC cells. Sesamol treatments caused downregulation of Harvey rat sarcoma viral oncogene homolog (HRAS) expression at protein and gene levels. Sesamol treatment modulates intrinsic apoptotic marker gene expression in OSCC cells. Overall results confirm the anti-cancer potential of sesamol and it seems to be a promising candidate for OSCC.

Cystatin-B Negatively Regulates the Malignant Characteristics of Oral Squamous Cell Carcinoma Possibly Via the Epithelium Proliferation/Differentiation Program

Disturbance in the proteolytic process is one of the malignant signs of tumors. Proteolysis is highly orchestrated by cysteine cathepsin and its inhibitors. Cystatin-B (CSTB) is a general cysteine cathepsin inhibitor that prevents cysteine cathepsin from leaking from lysosomes and causing inappropriate proteolysis. Our study found that CSTB was downregulated in both oral squamous cell carcinoma (OSCC) tissues and cells compared with normal controls. Immunohistochemical analysis showed that CSTB was mainly distributed in the epithelial structure of OSCC tissues, and its expression intensity was related to the grade classification. A correlation analysis between CSTB and clinical prognosis was performed using gene expression data and clinical information acquired from The Cancer Genome Atlas (TCGA) database. Patients with lower expression levels of CSTB had shorter disease-free survival times and poorer clinicopathological features (e.g., lymph node metastases, perineural invasion, low degree of differentiation, and advanced tumor stage). OSCC cell models overexpressing CSTB were constructed to assess the effects of CSTB on malignant biological behaviors and upregulation of CSTB inhibited cell proliferation, migration, and invasion in vitro. Weighted gene correlation network analysis (WGCNA) and gene set enrichment analysis (GSEA) were performed based on the TCGA data to explore potential mechanisms, and CSTB appeared to correlate with squamous epithelial proliferation-differentiation processes, such as epidermal cell differentiation and keratinization. Moreover, in WGCNA, the gene module most associated with CSTB expression (i.e., the brown module) was also the one most associated with grade classification. Upregulation of CSTB promoted the expression levels of markers (LOR, IVL, KRT5/14, and KRT1/10), reflecting a tendency for differentiation and keratinization in vitro. Gene expression profile data of the overexpressed CSTB cell line were obtained by RNA sequencing (RNA-seq) technology. By comparing the GSEA enrichment results of RNA-seq data (from the OSCC models overexpressing CSTB) and existing public database data, three gene sets (i.e., apical junction, G2/M checkpoint, etc.) and six pathways (e.g., NOTCH signaling pathway, glycosaminoglycan degradation, mismatch repair, etc.) were enriched in the data from both sources. Overall, our study shows that CSTB is downregulated in OSCC and might regulate the malignant characteristics of OSCC via the epithelial proliferation/differentiation program.

Targeting the genetic landscape of oral potentially malignant disorders has the potential as a preventative strategy in oral cancer

This study reviews the molecular landscape of oral potentially malignant disorders (OPMD). We examine the impact of tumour heterogeneity, the spectrum of driver mutations (TP53, CDKN2A, TERT, NOTCH1, AJUBA, PIK3CA, CASP8) and gene transcription on tumour progression. We comment on how some of these mutations impact cellular senescence, field cancerization and cancer stem cells. We propose that OPMD can be monitored more closely and more dynamically through the use of liquid biopsies using an appropriate biomarker of transformation. We describe new gene interactions through the use of a systems biology approach and we highlight some of the first studies to identify functional genes using CRISPR-Cas9 technology. We believe that this information has translational implications for the use of re-purposed existing drugs and/or new drug development. Further, we argue that the use of digital technology encompassing clinical and laboratory-based data will create relevant datasets for machine learning/artificial intelligence. We believe that therapeutic intervention at an early molecular premalignant stage should be an important preventative strategy to inhibit the development of oral squamous cell carcinoma and that this approach is applicable to other aerodigestive tract cancers.

Pluripotent Stem Cells: Cancer Study, Therapy, and Vaccination

INTRODUCTION

Pluripotent stem cells (PSCs) are promising tools for modern regenerative medicine applications because of their stemness properties, which include unlimited self-renewal and the ability to differentiate into all cell types in the body. Evidence suggests that a rare population of cells within a tumor, termed cancer stem cells (CSCs), exhibit stemness and phenotypic plasticity properties that are primarily responsible for resistance to chemotherapy, radiotherapy, metastasis, cancer development, and tumor relapse. Different therapeutic approaches that target CSCs have been developed for tumor eradication.

RESULTS AND DISCUSSION

In this review, we first provide an overview of different viewpoints about the origin of CSCs. Particular attention has been paid to views believe that CSCs are probably appeared through dysregulation of very small embryonic-like stem cells (VSELs) which reside in various tissues as the main candidate for tissue-specific stem cells. The expression of pluripotency markers in these two types of cells can strengthen the validity of this theory. In this regard, we discuss the common properties of CSCs and PSCs, and highlight the potential of PSCs in cancer studies, therapeutic applications, as well as educating the immune system against CSCs.

CONCLUSION

In conclusion, the resemblance of CSCs to PSCs can provide an appropriate source of CSC-specific antigens through cultivation of PSCs which brings to light promising ideas for prophylactic and therapeutic cancer vaccine development.