Critical pathways of oral squamous cell carcinoma: molecular biomarker and therapeutic intervention

A bibliometric analysis of programmed cell death in oral cancer literature: research patterns and emerging trends (2000-2024)

BACKGROUND

Programmed cell death (PCD) plays a crucial role in oral cancer pathogenesis and treatment. However, a comprehensive bibliometric analysis of the global research landscape in this field has not been conducted. This study aims to analyze the evolution and current trends of PCD research in oral cancer from 2000 to 2024.

METHODS

Publications were retrieved from the Web of Science Core Collection database using relevant keywords related to oral cancer and PCD. VOSviewer 1.6.20 and CiteSpace 6.1R6 software were employed to conduct bibliometric analysis, including publication trends, citation analysis, co-authorship networks, keyword co-occurrence, and research hotspots. The time span was set from January 2000 to December 2024.

RESULTS

A total of 963 publications were identified and analyzed. The annual publication output showed a steady increase, with a significant growth rate after 2010, dividing the study period into three distinct phases. The most productive countries were China (58.42%), South Korea (12.27%), and Japan (10.04%), with China Medical University and Kaohsiung Medical University being the leading institutions. Research hotspots evolved from traditional apoptosis studies to emerging forms of PCD such as autophagy, ferroptosis, and pyroptosis. Keyword analysis revealed three major research clusters: basic molecular mechanisms (centered around ROS and oxidative stress), clinical aspects (including prognosis and cell proliferation), and cell death pathways. Citation burst analysis identified emerging trends in targeting multiple PCD pathways simultaneously for oral cancer therapy, with special focus on treatment resistance and survival.

CONCLUSION

This bibliometric analysis provides a comprehensive overview of global research trends in PCD and oral cancer over the past two decades. The findings highlight the shift from basic mechanistic studies focusing on apoptosis to more diverse PCD pathways and translational research. Emerging research directions include the exploration of synergistic mechanisms among multiple PCD pathways, development of AI-based personalized treatment plans, investigation of microenvironment regulation of PCD, and application of novel drug delivery systems. These trends demonstrate the field's evolution toward more integrated, personalized approaches in oral cancer treatment. This study offers valuable insights for researchers and funding agencies to identify research gaps and potential collaboration opportunities in this rapidly developing field.

Tongluo Jiedu as an adjuvant therapy for oral cancer

Oral cancer is one of the malignant neoplasms that present major global health challenge. It is the sixth most prevalent type of cancer in the world, with a high incidence and mortality rate. This letter is a review of the study by Yin et al which was published in the World Journal of Clinical Cases (2024). The study evaluated the effect of Tongluo Jiedu as an adjuvant treatment for oral cancer. Over the years, there has been a continuous search for effective and less invasive treatments for oral cancer. This article emphasizes and discusses various therapeutic options currently available, and it highlights that early intervention and multidisciplinary management are crucial for improving outcomes. Traditional Chinese medicine, particularly Tongluo Jiedu, presents potential complementary approach to conventional oral cancer therapies. Future research on Tongluo Jiedu should be focused on validation of its efficacy and safety through large, well-designed clinical trials, as well as better understanding of the molecular mechanisms involved, and optimization of therapeutic combinations. Additionally, continuous education of health professionals is key to the effective and safe integration of this traditional medicine into clinical practice. Continuous research is essential for optimization of therapeutic strategies and for addressing the challenges presented by this neoplasm.

Network pharmacological analysis and experimental study of cucurbitacin B in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a malignant tumor with a high incidence and poor prognosis. Cucurbitacin B (CuB) is a tetracyclic triterpenoid small-molecule compound extracted from plants, such as Cucurbitaceae and Brassicaceae, which has powerful anticancer effects. However, the effect and mechanism of CuB on OSCC remain unclear. Within the framework of the current study, network pharmacology was used to analyze the relationship between CuB and OSCC. The network pharmacology analysis showed that CuB and OSCC share 134 common targets; among them, PIK3R1, SRC, STAT3, AKT1, and MAPK1 are the key targets. The molecular docking analysis showed that CuB binds five target proteins. The results of the enrichment analysis showed that CuB exerted effects on OSCC through various pathways; of these pathways, PI3K-AKT was the most important pathway. The results of the in vitro cell experiments showed that CuB could inhibit the proliferation and migration of SCC25 and CAL27 cells, block the cell cycle in the G2 phase, induce cell apoptosis, and regulate the protein expression of the PI3K-AKT signaling pathway. The results of the in vivo animal experiments showed that CuB could inhibit 4NQO-induced oral cancer in mice. Therefore, network pharmacology, molecular docking, cell experiments, and animal experiments showed that CuB could play a role in OSCC by regulating multiple targets and pathways.

Exploring the therapeutic potential of lipid-based nanoparticles in the management of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a highly malignant and invasive tumor with significant mortality and morbidity. Current treatment modalities such as surgery, radiotherapy, and chemotherapy encounter significant limitations, such as poor targeting, systemic toxicity, and drug resistance. There is an urgent need for novel therapeutic strategies that offer targeted delivery, enhanced efficacy, and reduced side effects. The advent of lipid-based nanoparticles (LNPs) offers a promising tool for OSCC therapy, potentially overcoming the limitations of current therapeutic approaches. LNPs are composed of biodegradable and biocompatible lipids, which minimize the risk of toxicity and adverse effects. LNPs can encapsulate hydrophobic drugs, improving their solubility and stability in the biological environment, thereby enhancing their bioavailability. LNPs demonstrate significantly higher ability to encapsulate lipophilic drugs than other nanoparticle types. LNPs offer excellent storage stability, minimal drug leakage, and controlled drug release, making them highly effective nanoplatforms for the delivery of chemotherapeutic agents. Additionally, LNPs can be modified by complexing them with specific target ligands on their surface. This surface modification allows the active targeting of LNPs to the tumors in addition to the passive targeting mechanism. Furthermore, the PEGylation of LNPs improves their hydrophilicity and enhances their biological half-life by reducing clearance by the reticuloendothelial system. This review aims to discuss current treatment approaches and their limitations, as well as recent advancements in LNPs for better management of OSCC.

Quercetin induces ferroptosis by inactivating mTOR/S6KP70 pathway in oral squamous cell carcinoma

Although recent studies increasingly suggest the potential anti-cancer effect of quercetin, the exact underlying mechanism remains poorly demonstrated in oral squamous cell carcinoma (oSCC). Therefore, our research explored the impacts of quercetin on the ferroptosis and mTOR/S6KP70 axis in oSCC cell lines. After treating oSCC cells with quercetin or indicated compounds and transfection with SLC7A11- or S6KP70-overexpressing plasmid, cell viability was detected by CCK-8 assay. The level of ferroptosis in oSCC cells was assessed by measuring ROS and GSH levels. The activation of mTOR/S6KP70 axis was assessed by Western blotting. Quercetin promoted ferroptosis in an mTOR/S6KP70-dependent manner to inhibit tumor growth in oSCC cells. Mechanistically, we revealed that quercetin induced lipid peroxidation and reduced GSH levels by repressing SLC7A11 expression in oSCC cells. Specifically, the effects of quercetin on ferroptosis and mTOR and S6KP70 phosphorylation were partially blocked by both mTOR agonist and S6KP70 overexpression. Moreover, mTOR inhibitor promoted ferroptosis in quercetin-treated oSCC cells. Our findings showed that ferroptosis may be a new anti-tumor mechanism of quercetin. Additionally, we identified that quercetin can target mTOR/S6KP70 cascade to inhibit the growth of oSCC cells.

RUVBL1 accelerates tongue squamous cell carcinoma by mediating CRaf/MEK/ERK pathway

RAF/MEK/ERK pathway is frequently activated in tumor. Therefore, this study will investigate the function of RUVBL1 (RAF-binding protein) in tongue squamous cell carcinoma (TSCC). Bioinformatics was performed to identify differentially expressed mRNAs (DE-mRNAs) in TCGA-oral squamous cell carcinoma, GSE13601, and GSE34105 datasets. A total of 672 shared DE-mRNAs were identified in three datasets, and they are regulating metastasis and angiogenesis. Patients with RUVBL1 low expression had high overall survival. Overexpressing RUVBL1 enhanced the viability, wound healing percentage, invasion, sphere formation, angiogenesis, and resistance to cisplatin and 5-fluorouracil in CAL-27 and SCC-4 cells, and the opposite results were obtained by knocking down RUVBL1. Moreover, overexpression of RUVBL1 bolstered tumor growth in vivo. Strikingly, RUVBL1 diminished the phosphorylation of CRAF Ser259, which led to activation of the MEK/ERK pathway. In conclusion, RUVBL1 contributes to the malignant biological behavior of TSCC via activating the CRAF/MEK/ERK pathway. This provides molecular mechanisms and perspectives for targeted therapy of the CRAF/MEK/ERK pathway.

Pyruvate Kinase Differentially Alters Metabolic Signatures during Head and Neck Carcinogenesis

During glycolysis, the muscle isoform of pyruvate kinase PKM2 produces ATP in exchange for dephosphorylation of phosphoenolpyruvate (PEP) into pyruvate. PKM2 has been considered as a tumor-promoting factor in most cancers, whereas the regulatory role of PKM2 during head and neck carcinogenesis remained to be delineated. PKM2 mRNA and protein expression was examined in head and neck tumorous specimens. The role of PKM2 in controlling cellular malignancy was determined in shRNA-mediated PKM2-deficient head and neck squamous cell carcinoma (HNSC) cells. In agreement with the results in other cancers, PKM2 expression is enriched in both mouse and human HNSC tissues. Nevertheless, PKM2 mRNA expression reversely correlated with tumor stage, and greater recurrence-free survival rates are evident in the PKM2high HNSC population, arguing that PKM2 may be tumor-suppressive. Multifaceted analyses showed a greater in vivo xenografic tumor growth and an enhanced cisplatin resistance in response to PKM2 loss, whereas PKM2 silencing led to reduced cell motility. At the molecular level, metabolic shifts towards mitochondrial metabolism and activation of oncogenic Protein kinase B (PKB/Akt) and extracellular signal-regulated kinase (ERK) signals were detected in PKM2-silencing HNSC cells. In sum, our findings demonstrated that PKM2 differentially modulated head and neck tumorigenicity via metabolic reprogramming.

Microneedles: structure, classification, and application in oral cancer theranostics

Oral cancer is a malignant tumor that threatens the health of individuals on a global scale. Currently available clinical treatment methods, including surgery, radiotherapy, and chemotherapy, significantly impact the quality of life of patients with systemic side effects. In the treatment of oral cancer, local and efficient delivery of antineoplastic drugs or other substances (like photosensitizers) to improve the therapy effect is a potential way to optimize oral cancer treatments. As an emerging drug delivery system in recent years, microneedles (MNs) can be used for local drug delivery, offering the advantages of high efficiency, convenience, and noninvasiveness. This review briefly introduces the structures and characteristics of various types of MNs and summarizes MN preparation methods. An overview of the current research application of MNs in different cancer treatments is provided. Overall, MNs, as a means of transporting substances, demonstrate great potential in oral cancer treatments, and their promising future applications and perspectives of MNs are outlined in this review.

Fatty Liver and Risk of Head and Neck Cancer in Type 2 Diabetes Mellitus: A Nationwide Cohort Study

This study is aimed at investigating the association between NAFLD and the risk of HNC separately based on cancer site using a large population-based cohort of patients with T2DM. The data used in this population-based retrospective cohort study were provided by the Korean National Health Insurance Service. The Cox proportional hazards model was used to estimate multivariable adjusted hazard ratios and 95% CIs for the association of the fatty liver index (FLI) and the risk of HNC. During the mean 6.9 years of follow-up, approximately 25.4% of the study cohort had NAFLD, defined as an FLI ≥60. A total of 3543 HNC cases were identified. Overall, patients with a higher FLI had a significantly higher risk of HNC in the oral cavity, pharynx, and larynx compared with patients with an FLI <30. An association was not observed between salivary gland cancer and FLI. There was no association between obesity and HNC. However, obese patients showed a lower risk of cancer for the oral cavity (p = 0.040), pharynx (p = 0.009), and larynx (p < 0.001) than non-obese patients with the same FLI level. Neither obesity nor smoking affected the association between FLI- and HNC-risk in stratified analyses. In T2DM patients, NAFLD was associated with an increased risk of developing HNC in the oral cavity, pharynx, and larynx, but not in the salivary gland.

Targeting the PI3K/AKT/mTOR and RAF/MEK/ERK pathways for cancer therapy

The PI3K/AKT/mTOR and RAF/MEK/ERK pathways are commonly activated by mutations and chromosomal translocation in vital targets. The PI3K/AKT/mTOR signaling pathway is dysregulated in nearly all kinds of neoplasms, with the component in this pathway alternations. RAF/MEK/ERK signaling cascades are used to conduct signaling from the cell surface to the nucleus to mediate gene expression, cell cycle processes and apoptosis. RAS, B-Raf, PI3K, and PTEN are frequent upstream alternative sites. These mutations resulted in activated cell growth and downregulated cell apoptosis. The two pathways interact with each other to participate in tumorigenesis. PTEN alterations suppress RAF/MEK/ERK pathway activity via AKT phosphorylation and RAS inhibition. Several inhibitors targeting major components of these two pathways have been supported by the FDA. Dozens of agents in these two pathways have attracted great attention and have been assessed in clinical trials. The combination of small molecular inhibitors with traditional regimens has also been explored. Furthermore, dual inhibitors provide new insight into antitumor activity. This review will further comprehensively describe the genetic alterations in normal patients and tumor patients and discuss the role of targeted inhibitors in malignant neoplasm therapy. We hope this review will promote a comprehensive understanding of the role of the PI3K/AKT/mTOR and RAF/MEK/ERK signaling pathways in facilitating tumors and will help direct drug selection for tumor therapy.

Deoxypodophyllotoxin Induces ROS-Mediated Apoptosis by Modulating the PI3K/AKT and p38 MAPK-Dependent Signaling in Oral Squamous Cell Carcinoma

Deoxypodophyllotoxin (DPT), a naturally occurring flavonolignan, possesses several pharmacological properties, including anticancer property. However, the mechanisms underlying DPT mode of action in oral squamous cell carcinoma (OSCC) remain unknown. This study aimed to investigate the anticancer effects of DPT on OSCC and the underlying mechanisms. Results of the MTT assay revealed that DPT significantly reduced the cell viability in a time- and dose-dependent manner. Flow cytometry analysis revealed that DPT induces apoptosis in OSCC cells in a dose-dependent manner. Moreover, DPT enhanced the production of mitochondrial reactive oxygen species (ROS) in OSCC cells. Mechanistically, DPT induced apoptosis in OSCC cells by suppressing the PI3K/AKT signaling pathway while activating the p38 MAPK signaling to regulate the expression of apoptotic proteins. Treatment with SC79, an AKT activator, reversed the effects of DPT on AKT signaling in OSCC cells. Taken together, these results provide the basis for the use of DPT in combination with conventional chemotherapy for the treatment of oral cancer.

p-S6 as a Prognostic Biomarker in Canine Oral Squamous Cell Carcinoma

Scarce information exists on the role of mTOR pathway proteins and their association to aggressiveness and prognosis of patients with canine oral cancers. We aimed to investigate the activated form of mTOR and its downstream S6 protein in canine oral squamous cell carcinoma (OSCC), and to evaluate potential associations between protein expression and clinic-pathologic variables and survival. For that we analysed p-mTOR and p-S6 protein expression by immunohistochemistry in 61 canine OSCCs. Multivariate analysis was conducted to examine their role in patients’ cancer-specific survival (CSS). p-mTOR and p-S6 expression were present in almost all cases. High-expression of p-mTOR was observed in 44 (72.1%) cases using extent score and 52 (85.2%) cases using intensity score. For p-S6, high expression was observed in 53 (86.9%) cases using extent score and in 54 (88.5%) cases using intensity score. An independent prognostic value for p-S6 extension (p = 0.027), tumour stage (p = 0.013) and treatment (p = 0.0009) was found in patients’ CSS analysis. Our data suggest that p-mTOR and p-S6 proteins are commonly expressed in canine OSCC and p-S6 expression is correlated with poor CSS in dogs with OSCC. More studies should be performed to identify possible therapeutic targets related with mTOR pathway for these patients.