Oral cancer: Current role of radiotherapy and chemotherapy

Impact of oral care intervention on quality of life of patients with oral cancer undergoing radiotherapy in Sri Lanka: A quasi-experimental study

BACKGROUND

Radiotherapy is used to treat oral cancer, yet it negatively affects patients' health-related quality of life (HRQOL). The aim was to evaluate the impact of an oral healthcare intervention on HRQOL of patients with oral cancer who receive radiotherapy with or without chemotherapy.

METHODS

An oral healthcare intervention was provided to 41 patients with oral cancer before radiotherapy (fluoride varnish application, scaling, permanent restorations, adjustment of sharp teeth, and extraction of teeth with questionable prognosis, oral hygiene instructions), during, and 3 months after radiotherapy (baking soda mouthwash, artificial saliva spray). EORTC QLQ-H&N35 was used to compare the HRQOL of the intervention and control groups, with the latter having received routine oral healthcare.

RESULTS

The intervention group showed lesser values for HRQOL domains and items indicating fewer side effects during the last week of radiotherapy and 3 months after, compared to the control group. Most of the changes in HRQOL were significantly less in the intervention group compared to the control group (p < 0.01).

CONCLUSION

The oral healthcare intervention effectively reduced the effect of radiotherapy and positively impacted on HRQOL of patients with oral cancer.

Iodine-125 seed inhibits proliferation and promotes apoptosis of cholangiocarcinoma cells by inducing the ROS/p53 axis

With advances in radioactive particle implantation in clinical practice, Iodine-125 (125I) seed brachytherapy has emerged as a promising treatment for cholangiocarcinoma (CCA), showing good prognosis; however, the underlying molecular mechanism of the therapeutic effect of 125I seed is unclear. To study the effects of 125I seed on the proliferation and apoptosis of CCA cells. CCA cell lines, RBE and HCCC-9810, were treated with reactive oxygen species (ROS) scavenger acetylcysteine (NAC) or the p53 functional inhibitor, pifithrin-α hydrobromide (PFTα). Cell counting kit-8 (CCK-8) assay, 5-bromo-2-deoxy-uridine (BrdU) staining, and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay and flow cytometry assay were performed to test the radiation-sensitivity of 125I seed toward CCA cells at different radiation doses (0.4 mCi and 0.8 mCi). 2,7-dichlorofluorescein diacetate (DCF-DA) assay, real-time quantitative polymerase chain reaction (RT-qPCR), and western blot analysis were performed to assess the effect of 125I seed on the ROS/p53 axis. A dose-dependent inhibitory effect of 125I seeds on the proliferation of CCA cells was observed. The 125I seed promoted apoptosis of CCA cells and induced the activation of the ROS/p53 pathway in a dose-dependent manner. NAC or PFTα treatment effectively reversed the stimulatory effect of 125I seed on the proliferation of CCA cells. NAC or PFTα suppressed apoptosis and p53 protein expression induced by the 125I seed. 125I seed can inhibit cell growth mainly through the apoptotic pathway. The mechanism may involve the activation of p53 and its downstream apoptotic pathway by up-regulating the level of ROS in cells.

High expression of ACTL6A leads to poor prognosis of oral squamous cell carcinoma patients through promoting malignant progression

OBJECTIVE

The aim was to research ACTL6A's role in oral squamous cell carcinoma (OSCC).

METHODS

OSCC and normal samples were obtained from patients and public databases. GSEA was performed. CIBERSORT was utilized to analyze immune landscape. Kaplan-Meier survival analysis and multivariate Cox regression analysis were conducted. After knocking down ACTL6A, we performed MTT assay, transwell assays, and flow cytometry to detect the impact of knockdown.

RESULTS

ACTL6A expressed higher in OSCC samples than normal samples. The CNV and mutation rate of TP53 was higher in ACTL6A high-expression group. TFs E2F7 and TP63 and miRNA hsa-mir-381 were significantly related to ACTL6A. ACTL6A could influence immune microenvironment of OSCC. Knockdown of ACTL6A inhibited OSCC cells' proliferation, migration, and invasion. ACTL6A was able to predict OSCC prognosis independently.

CONCLUSION

ACTL6A expressed higher in OSCC than normal samples and it could be used as an independent prognostic marker in OSCC patients.

Are oral cancers effectively palliated with radiotherapy? Outcomes of treatment with a modified QUAD SHOT regimen

BACKGROUND

This study assessed a palliative radiotherapy regimen using daily radiation over 4 days for three courses in inoperable head and neck cancers, emphasizing oral primary cancers.

METHODS

Retrospective data of 116 patients treated with a daily dose of 3.6-3.7 Gy in four fractions over 4 days to a total of three courses, with a 2-week gap after every course, were analyzed for survival outcomes. A subgroup analysis was done for oral cancer.

RESULTS

Ninety-nine (85%) completed three courses. Overall subjective response rate was 77%. Median overall survival and progression-free survival were 12 months (95% confidence interval [CI]: 8-20) and 8 months (95% CI: 6-10), with numerically higher overall survival in oral cancer. The treatment was well tolerated, with no on-treatment hospitalization or grade 3-4 toxicities.

CONCLUSION

The modified QUAD SHOT regimen is practical for palliation in head and neck cancers.

Cellular mechanisms mediating the anti-cancer effects of carnosol on gingiva carcinoma

Carnosol, a rosemary polyphenol, displays anticancer properties and is suggested as a safer alternative to conventional surgery, radiotherapy, and chemotherapy. Given that its effects on gingiva carcinoma have not yet been investigated, the aim of this study was to explore its anti-tumor selectivity and to unravel its underlying mechanisms of action. Hence, oral tongue and gingiva carcinoma cell lines exposed to carnosol were analyzed to estimate cytotoxicity, cell viability, cell proliferation, and colony formation potential as compared with those of normal cells. Key cell cycle and apoptotic markers were also measured. Finally, cell migration, oxidative stress, and crucial cell signaling pathways were assessed. Selective anti-gingiva carcinoma activity was disclosed. Overall, carnosol mediated colony formation and proliferation suppression in addition to cytotoxicity induction. Cell cycle arrest was highlighted by the disruption of the c-myc oncogene/p53 tumor suppressor balance. Carnosol also increased apoptosis, oxidative stress, and antioxidant activity. On a larger scale, the alteration of cell cycle and apoptotic profiles was also demonstrated by QPCR array. This was most likely achieved by controlling the STAT5, ERK1/2, p38, and NF-ĸB signaling pathways. Lastly, carnosol reduced inflammation and invasion ability by modulating IL-6 and MMP9/TIMP-1 axes. This study establishes a robust foundation, urging extensive inquiry both in vivo and in clinical settings, to substantiate the efficacy of carnosol in managing gingiva carcinoma.

Chaga mushroom extract suppresses oral cancer cell growth via inhibition of energy metabolism

Oral cancer stands as a prevalent maligancy worldwide; however, its therapeutic potential is limited by undesired effects and complications. As a medicinal edible fungus, Chaga mushroom (Inonotus obliquus) exhibits anticancer effects across diverse cancers. Yet, the precise mechanisms underlying its efficacy remain unclear. We explored the detailed mechanisms underlying the anticancer action of Chaga mushroom extract in oral cancer cells (HSC-4). Following treatment with Chaga mushroom extracts, we analyzed cell viability, proliferation capacity, glycolysis, mitochondrial respiration, and apoptosis. Our findings revealed that the extract reduced cell viability and proliferation of HSC-4 cells while arresting their cell cycle via suppression of STAT3 activity. Regarding energy metabolism, Chaga mushroom extract inhibited glycolysis and mitochondrial membrane potential in HSC-4 cells, thereby triggering autophagy-mediated apoptotic cell death through activation of the p38 MAPK and NF-κB signaling pathways. Our results indicate that Chaga mushroom extract impedes oral cancer cell progression, by inhibiting cell cycle and proliferation, suppressing cancer cell energy metabolism, and promoting autophagy-mediated apoptotic cell death. These findings suggest that this extract is a promising supplementary medicine for the treatment of patients with oral cancer.

Can interventional radiotherapy (brachytherapy) be an alternative to surgery in early-stage oral cavity cancer? A systematic review

PURPOSE

Brachytherapy (BT), also known as interventional radiotherapy (IRT), has proven its utility in the treatment of localized tumors. The aim of this review was to examine the efficacy of modern BT in early-stage oral cavity cancer (OCC) in terms of local control (LC), overall survival (OS), disease-free survival (DFS), cancer-specific survival (CSS), and safety.

METHODS

The SPIDER framework was used, with sample (S), phenomena of interest (PI), design (D), evaluation (E), and research type (R) corresponding to early-stage oral cavity cancer (S); BT (PI); named types of qualitative data collection and analysis (D); LC, OS, DFS, CSS, and toxicity (E); qualitative method (R). Systematic research using PubMed and Scopus was performed to identify full articles evaluating the efficacy of BT in patients with early-stage OCC. The studies were identified using medical subject headings (MeSH). We also performed a PubMed search with the keywords "brachytherapy oral cavity cancer, surgery." The search was restricted to the English language. The timeframe 2002-2022 as year of publication was considered. We analyzed clinical studies of patients with OCC treated with BT alone only as full text; conference papers, surveys, letters, editorials, book chapters, and reviews were excluded.

RESULTS

The literature search resulted in 517 articles. After the selection process, 7 studies fulfilled the inclusion criteria and were included in this review, totaling 456 patients with early-stage node-negative OCC who were treated with BT alone (304 patients). Five-year LC, DFS, and OS for the BT group were 60-100%, 82-91%, and 50-84%, respectively.

CONCLUSION

In conclusion, our review suggests that BT is effective in the treatment of early-stage OCC, particularly for T1N0 of the lip, mobile tongue, and buccal mucosa cancers, with good functional and toxicity profiles.

Lip prosthesis as a palliative care modality for a head and neck cancer patient-A case report

The present case report describes the prosthetic management following partial loss of free-fibular osteocutaneous flap in an irradiated patient diagnosed with recurrent head and neck cancer. The patient presented with constant drooling of oral fluids due to an anatomically deficient lower lip. Salvage reconstructive surgery was not considered feasible due to past history of recurrence, multiple surgeries and radiotherapy, and financial constraints. An adhesive-retained interim silicone prosthesis was fabricated to alleviate the functional and psychosocial morbidity. The prosthesis served to restore the oro-facial seal to prevent constant drooling of oral fluids. It also aided in providing an excellent aesthetic solution to palliate the psychological suffering experienced by the patient due to lost facial contours.

Comparison of a daily and alternate-day photobiomodulation protocol in the prevention of oral mucositis in patients undergoing radiochemotherapy for oral cancer: a triple-blind, controlled clinical trial

BACKGROUND

Preventive Photobiomodulation Therapy (PBMT) significantly reduces oral mucositis (OM) severity in patients undergoing Radiochemotherapy (RCT) for the treatment of oral cancer, but daily applications generate cost, overload the dental team, and reduce the number of patients assisted.To evaluate the effectiveness of two PBMT protocols in preventing OM in patients undergoing RCT for oral cancer.

MATERIAL AND METHODS

16 patients diagnosed with oral cancer undergoing RCT were included, equally divided into two groups: a group treated daily with PBMT, and another group also submitted to daily treatment, however, performing the application of PBMT every three days, interspersed with a simulation of PBMT (placebo). A red laser was used (~660 nm), 0.1W power, 1J of energy applied per point, 9 points per area (labial mucosa, buccal mucosa, lateral borders of the tongue, body of the tongue, and floor of the mouth) from the beginning of RCT until the end of the oncological treatment. Daily assessments were performed regarding OM scores, the World Health Organization (WHO) pain scale, and the visual analog scale (VAS). Weight, salivary flow (SGAPP), OHIP-14, and DMFT were evaluated on the initial and final days of RT. OM incidence and clinical data were compared by Pearson's chi-square test or Fisher's exact test. Pain and other scale scores were compared using the Mann-Whitney and Friedman/Dunn tests (SPSS v20.0 p<0.05).

RESULTS

In the group with PBMT on alternate days, there was an increase in the frequency of grade 2 and grade 3 oral mucositis and an increased risk of grade 2 oral mucositis, in addition to higher mean pain scores and greater reduction in salivary flow.

CONCLUSIONS

The daily PBMT protocol proved more effective in controlling the frequency and severity of OM, pain, and salivary flow.

Exosomes: A Cutting-Edge Theranostics Tool for Oral Cancer

Exosomes are a subpopulation of extracellular vesicles (EVs) secreted by cells. In cancer, they are key cellular messengers during cancer development and progression. Tumor-derived exosomes (TEXs) promote cancer progression. In oral cancer, the major complication is oral squamous cell carcinoma (OSCC). Exosomes show strong participation in several OSCC-related activities such as uncontrolled cell growth, immune suppression, angiogenesis, metastasis, and drug and therapeutic resistance. It is also a potential biomarker source for oral cancer. Some therapeutic exosome sources such as stem cells, plants (it is more effective compared to others), and engineered exosomes reduce oral cancer development. This therapeutic approach is effective because of its specificity, biocompatibility, and cell-free therapy (it reduced side effects in cancer treatment). This article highlights exosome-based theranostics signatures in oral cancer, clinical trials, challenges of exosome-based oral cancer research, and future improvements. In the future, exosomes may become an effective and affordable solution for oral cancer.

The Use of Immune Regulation in Treating Head and Neck Squamous Cell Carcinoma (HNSCC)

Immunotherapy has emerged as a promising new treatment modality for head and neck cancer, offering the potential for targeted and effective cancer management. Squamous cell carcinomas pose significant challenges due to their aggressive nature and limited treatment options. Conventional therapies such as surgery, radiation, and chemotherapy often have limited success rates and can have significant side effects. Immunotherapy harnesses the power of the immune system to recognize and eliminate cancer cells, and thus represents a novel approach with the potential to improve patient outcomes. In the management of head and neck squamous cell carcinoma (HNSCC), important contributions are made by immunotherapies, including adaptive cell therapy (ACT) and immune checkpoint inhibitor therapy. In this review, we are focusing on the latter. Immune checkpoint inhibitors target proteins such as programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) to enhance the immune response against cancer cells. The CTLA-4 inhibitors, such as ipilimumab and tremelimumab, have been approved for early-stage clinical trials and have shown promising outcomes in terms of tumor regression and durable responses in patients with advanced HNSCC. Thus, immune checkpoint inhibitor therapy holds promise in overcoming the limitations of conventional therapies. However, further research is needed to optimize treatment regimens, identify predictive biomarkers, and overcome potential resistance mechanisms. With ongoing advancements in immunotherapy, the future holds great potential for transforming the landscape of oral tumor treatment and providing new hope for patients.

Anti-cancer effects of green synthesized gold nanoparticles using leaf extract of Annona muricata. L against squamous cell carcinoma cell line 15 through apoptotic pathway

Background

Oral cancer remains one of the most dreadful diseases in developing nations. Currently, there has been a rise in the prevalence of tongue squamous cell carcinoma (SCC), with a poor prognosis. The use of standard treatment approaches against oral cancer patients brings about several side effects. In recent years, nanomedicine has provided a versatile platform for developing new targeted therapeutic modalities. However, safety remains a concern in the synthesis of nanoparticles (NPs). Therefore, the present study aims to synthesize safer phytoconstituent-mediated gold NPs (AuNPs) utilizing leaf extracts of Annona muricata, where the biochemical components of the plant leaf act as the reducing and capping agents in the synthesis of NPs, and to evaluate its anti-cancer activity against SCC.

Materials and Methods

In this in vitro experimental study, AuNPs were synthesized through an effective, simple, and ecologically sound green synthesis method. After characterization of these synthesized AuNPs, in vitro assays such as 3-(4, 5-dimethylthiazole2-yl)-2, 5-biphenyl tetrazolium bromide, wound healing, and clonogenic assays were carried out to investigate the anti-cancer potential of green synthesized AuNPs in the human tongue SCC cell line (SCC-15), and the possible mechanism of action was evaluated through gene and protein expression analysis of Bax, Bcl-2, and p53 genes. The results were expressed as mean ± standard deviation using Statistical Package for Social Sciences (SPSS) 20.0 software and Student's t-test was performed for experimental data. P ≤0.05 were considered statistically significant.

Results

The in vitro assays demonstrated that the synthesized AuNPs are exhibiting anti-cancer activity by apoptosis of SCC-15 cells in a dose-dependent manner. Further, it also revealed a highly significant decrease in anti-apoptotic Bcl-2 gene expression, whereas pro-apoptotic genes p53 and Bax revealed a highly significant increase, which is statistically significant compared to the control (P < 0.05).

Conclusion

Our findings demonstrated that the AuNPs synthesized from A. muricata leaf extract could act as a novel anticancer agent, particularly against SCC, after further scrutiny.

Systemic and Local Administration of a Dual-siRNA Complex Efficiently Inhibits Tumor Growth and Bone Invasion in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) accounts for nearly 90% of oral and oropharyngeal cancer cases and is characterized by high mortality and poor prognosis. RNA-based gene therapies have been developed as an emerging option for cancer treatment, but it has not been widely explored in OSCC. In this work, we developed an efficient siRNA cationic micelle DOTAP-mPEG-PCL (DMP) by self-assembling the cationic lipid DOTAP and monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) (mPEG-PCL) polymer. We tested the characteristics and transformation efficiency of this micelle and combined DMP with siRNA targeting STAT3 and TGF-β to evaluate the antitumor effect and bone invasion interfering in vitro and in vivo. The average size of the DMP was 28.27 ± 1.62 nm with an average zeta potential of 54.60 ± 0.29 mV. The DMP/siRNA complex showed high delivery efficiency, with rates of 97.47 ± 0.42% for HSC-3. In vitro, the DMP/siSTAT3 complex exhibited an obvious cell growth inhibition effect detected by MTT assay (an average cell viability of 25.1%) and clonogenic assay (an average inhibition rate of 51.9%). Besides, the supernatant from HSC-3 transfected by DMP/siTGF-β complexes was found to interfere with osteoclast differentiation in vitro. Irrespective of local or systemic administration, DMP/siSTAT3+siTGF-β showed antitumor effects and bone invasion inhibition in the OSCC mice mandibular invasion model according to tumor volume assays and Micro-CT scanning. The complex constructed by DMP cationic micelles and siSTAT3+siTGF-β represents a potential RNA-based gene therapy delivery system for OSCC.

Comparative evaluation of quality of life in oral cancer patients undergoing 3-dimensional conformal radiation therapy with or without concomitant chemotherapy - A longitudinal study

OBJECTIVES

To assess and compare the quality of life (QOL) in Oral Cancer patients undergoing 3-DCRT with or without concomitant Chemotherapy at three different time intervals.

MATERIALS AND METHODS

This unicentric longitudinal study included 50 patients of oral cancer undergoing 3-DCRT with or without concomitant chemotherapy. QOL was recorded using the EORTC H and N 35 Questionnaire at baseline, end of treatment (EOT), and 3 months after treatment.

RESULTS

Maximum deterioration of most QOL domains were noted at End of treatment (EOT) in all the patients. A highly statistically significant difference was noted between different time intervals with the highest scores noted at the EOT (P < 0.01). There was a statistically significant difference in patients undergoing 3DCRT with chemotherapy when compared to those with 3DCRT without chemotherapy (P < 0.05).

CONCLUSION

There is substantial deterioration in QOL at the EOT after head-neck irradiation by 3-DCRT with or without concomitant Chemotherapy although it gradually improves over time. However, 3DCRT results in clinically meaningful and statistically better QOL scores at 3 months after treatment compared to baseline and EOT.

Role of Natural Killer Cells as Cell-Based Immunotherapy in Oral Tumor Eradication and Differentiation Both In Vivo and In Vitro

Despite advancements in the field of cancer therapeutics, the five-year survival rate remains low in oral cancer patients. Therefore, the effective therapeutics are needed against oral cancer. Also, several studies including ours, have shown severely suppressed function and number of NK cells in oral cancer patients. In this review, we discuss the approach to inhibit the tumor growth and metastasis by direct killing or NK cell-mediated tumor differentiation. This review also provides an overview on supercharging NK cells using osteoclasts and probiotic bacteria, and their efficacy as cancer immunotherapeutic in humanized-BLT mice.

Long-term follow-up of osteoradionecrosis of the mandible

AIM

Investigating the prevalence of mandibular ORN in a single Swedish Oncology Center.

METHODS

A total of 450 patients, treated with radiotherapy for squamous cell carcinoma in the oropharynx between 2004 and 2014 were included. Three different techniques of radiotherapy were studied. ORN diagnosis was set when clinical signs according to Marx were observed, or if radiological signs were staged according to Schwartz and Kagan.

RESULTS

Using the staging system, 90 patients (20%) were diagnosed with ORN. The mean age of the ORN patients was 56.6 years, the older the patient the lower the risk of developing ORN (p = .01). The risk of developing ORN for patients receiving Intensity Modulated Radiotherapy was lower compared to patients treated with the other techniques in the multivariable analysis. Brachytherapy significantly increases the risk of ORN. The risk of ORN increased by 8% each year after radiation (p = .04). The mean time to the ORN diagnosis was 3.9 years. In the multivariate analysis, the risk of ORN increased by 13% each year after radiation (p = .0013).

CONCLUSION

The mean radiation dose was of greater importance for the risk of ORN than the maximum dose. Elderly people with oropharyngeal cancer were less prone to develop ORN.

Surgical Management of Oral Cavity Cancer: Experience at a Tertiary Care Centre in Jamshedpur

Background Cancer of the oral cavity is very common in Eastern India. This is due to the lack of awareness that chewing tobacco causes oral cancer. Because of poor economic condition and lack of access to healthcare, patients in this region often present at an advanced stage of the disease when they become symptomatic. A retrospective study was conducted at Tata Main Hospital, Jamshedpur, India, to know the epidemiology and recurrence of oral cavity cancer in this region. Materials and methods We conducted a retrospective study of oral cavity cancer patients operated at Tata Main Hospital, Jamshedpur, from January 2018 to June 2023. Data were collected from the surgical register, operation theatre notes, case sheets and hospital online data. The following parameters were observed in this study: a) age, b) gender, c) site of cancer, d) histology, e) stage of disease at presentation, f) type of neck dissection, g) margin status on the final histopathology report, h) node positivity, i) presence of perineural invasion or lymphovascular invasion and j) recurrence.  Results A total of 218 patients were operated between January 2018 and June 2023. The most common site for oral cavity cancer was the buccal mucosa with the involvement of the lower alveolus (168 patients, 77.06%), followed by the tongue (27 patients, 12.38%). Two-hundred seventeen patients were diagnosed with squamous cell carcinoma (SCC), and one patient had epithelioid sarcoma on the biopsy report. The most common stage of presentation was stage IVa (180 patients, 82.56%), followed by stage III (16 patients, 7.34%). The most frequent neck dissection performed was modified radical neck dissection (MRND) sacrificing the sternocleidomastoid muscle (SCM) and preserving the internal juglar vein (IJV) and spinal accessory nerve (SAN) (176 patients, 80%). The margin was positive for 10 patients. Node positivity on the final histopathology report grouped according to the clinical stage are as follows: stage I (33.33%), stage II (60%), stage III (75%) and stage IV (86.67%). Similarly, the presence of lymphovascular or perineural invasion on the final histopathology report grouped according to the clinical stage is as follows: stage I (0%), stage II (20%), stage III (25%) and stage IV (55.55 %). Fifteen patients lost to follow-up. Recurrence was noted in 11 patients (5.04%). Patients presenting with stages I and II had no recurrence, whereas three out of 16 patients in stage III (1.1%) and eight out of 180 patients in stage IV (4.44%) had recurrence. Conclusion SCC is the most common type of oral cavity cancer in Eastern India. It is strongly related to tobacco chewing habit. Since most of the patients in this part of the country present with an advanced stage of the disease, awareness regarding cessation of tobacco use and screening can be beneficial to the general population.

SOX2 promotes a cancer stem cell-like phenotype and local spreading in oral squamous cell carcinoma

Emerging evidence shows that oral squamous cell carcinoma (OSCC) invasiveness can be attributed to a small subpopulation of cancer stem cells (CSCs) in the bulk of the tumor. However, the presence of CSCs in the OSCC close resection margins is still poorly unexplored. Here, we found that BMI1, CD44, SOX2, OCT4, UBE2C, CXCR4 CSCs marker genes are significantly upregulated, while IGF1-R, KLF4, ALDH1A1, CD133, FAM3C are downregulated in the tumor core vs healthy mucosa of 24 patients with OSCC. Among these, SOX2 appears also upregulated in the tumor close margin vs healthy mucosa and this significantly correlates with tumor size and lymph node compromise. In vitro analyses in CAL27 and SCC15 tongue squamous cell carcinoma cell lines, show that SOX2 transient knockdown i) promotes the mesenchymal-to-epithelial transition, ii) smooths the invasiveness, iii) attenuates the 3D tumor sphere-forming capacity, and iv) partially increases the sensitivity to cisplatin treatment. Overall, our study highlights that the OSCC close margins can retain CSC-specific markers. Notably, SOX2 may represent a useful CSCs marker to predict a more aggressive phenotype and a suitable target to prevent local invasiveness.

Emerging histological and serological biomarkers in oral squamous cell carcinoma: Applications in diagnosis, prognosis evaluation and personalized therapeutics (Review)

Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral cavity and accounts for >90% of all oral cancers. Despite advances in diagnostic procedures and therapeutic interventions, overall survival has not improved significantly in recent decades, primarily due to late diagnosis, locoregional recurrence and treatment resistance. Identifying reliable biomarkers for early detection, prognosis evaluation and treatment response prediction is critical for improving clinical outcomes in patients with OSCC. In the present review, the prognostic and predictive utility of circulating biomarkers, such as circulating tumour cells, serological biomarkers and histological and genetic biomarkers, were explored in the context of OSCC. In addition, the potential role of immune checkpoints in the treatment of OSCC was highlighted and the rapidly evolving field of liquid biopsy and its potential to revolutionize diagnosis, prognosis evaluation and treatment were examined. The existing evidence for the clinical utility of these biomarkers was critically evaluated and the challenges and limitations associated with their introduction into routine clinical practice were addressed. In conclusion, the present review highlights the promising role of biomarkers in improving the current understanding of the pathogenesis of OSCC and offers potential avenues for improving patient care through personalized medicine approaches.

Necroptosis in human cancers with special emphasis on oral squamous cell carcinoma

Necroptosis is a type of caspase independent 'programmed or regulated' necrotic cell death that has a morphological resemblance to necrosis and mechanistic analogy to apoptosis. This type of cell death requires RIPK1, RIPK3, MLKL, death receptors, toll like receptors, interferons, and various other proteins. Necroptosis is implicated in plethora of diseases like rheumatoid arthritis, Alzheimer's disease, Crohn's disease, and head and neck cancers including oral squamous cell carcinoma. Oral carcinomas show dysregulation or mutation of necroptotic proteins, mediate antitumoral immunity, activate immune response and control tumor progression. Necroptosis is known to play a dual role (pro tumorigenic and anti-tumorigenic) in cancer progression and targeting this pathway could be an effective approach in cancer therapy. Necroptosis based chemotherapy has been proposed in malignancies, highlighting the importance of necroptotic pathway to overcome apoptosis resistance and serve as a "fail-safe" pathway to modulate cancer initiation, progression, and metastasis. However, there is dearth of information regarding the use of necroptotic cell death mechanism in the treatment of oral squamous cell carcinoma. In this review, we summarise molecular mechanism of necroptosis, and its protumorigenic and antitumorigenic role in cancers to shed light on the possible therapeutic significance of necroptosis in oral squamous cell carcinoma.

Application Value of Antimicrobial Peptides in Gastrointestinal Tumors

Gastrointestinal cancer is a common clinical malignant tumor disease that seriously endangers human health and lacks effective treatment methods. As part of the innate immune defense of many organisms, antimicrobial peptides not only have broad-spectrum antibacterial activity but also can specifically kill tumor cells. The positive charge of antimicrobial peptides under neutral conditions determines their high selectivity to tumor cells. In addition, antimicrobial peptides also have unique anticancer mechanisms, such as inducing apoptosis, autophagy, cell cycle arrest, membrane destruction, and inhibition of metastasis, which highlights the low drug resistance and high specificity of antimicrobial peptides. In this review, we summarize the related studies on antimicrobial peptides in the treatment of digestive tract tumors, mainly oral cancer, esophageal cancer, gastric cancer, liver cancer, pancreatic cancer, and colorectal cancer. This paper describes the therapeutic advantages of antimicrobial peptides due to their unique anticancer mechanisms. The length, net charge, and secondary structure of antimicrobial peptides can be modified by design or modification to further enhance their anticancer effects. In summary, as an emerging cancer treatment drug, antimicrobial peptides need to be further studied to realize their application in gastrointestinal cancer diseases.

Oncologic Outcome in Advanced Oral Squamous Cell Carcinoma After Refusal of Recommended Adjuvant Therapy

Importance

Clinicians may be confronted with patients refusing recommended adjuvant therapy (AT) after the primary resection of an advanced oral squamous cell carcinoma (OSCC). However, for this tumor entity, data are lacking regarding the oncological outcomes and associated factors after refusal of AT.

Objective

To evaluate the difference in survival and disease recurrence for patients with and without recommended AT after resection of advanced OSCC.

Design, Setting, and Participants

In this single-center retrospective matched cohort study, patients with advanced OSCC who refused recommended AT between January 2010 and December 2021 were matched 1:1 according to Union for International Cancer Control tumor staging with patients who completed AT.

Exposures

Patients with advanced OSCC who refused or completed recommended AT between 2010 and 2021.

Main Outcomes and Measures

The primary outcome of this study was the comparison of overall survival (OS) and recurrence-free survival (RFS) between the 2 study groups.

Results

A total of 82 patients (mean [SD] age at time of surgery, 68.0 [11.3] years; 38 [46.3%] female, 44 [53.7%] male) with and without AT (41 per study group) were included in the analysis. Patients refusing AT developed more frequent disease recurrence than patients who completed AT (61.0% vs 26.8%; difference, 34.2%; odds ratio, 4.26; 95% CI, 1.68-10.84). In addition, patients who refused AT presented with lower 2-year OS (72.7% vs 88.6%; difference, 15.9%; 95% CI, 8.6%-40.6%) and much lower 2-year RFS (39.1% vs 74.2%; difference, 35.1%; 95% CI, 0.2%-70.5%). In the patient cohort who rejected AT, a worse OS was associated with female sex (48.6% vs 90.5%; difference, 41.9%; 95% CI, 0.6%-84.4%), pT1-2 category (57.1% vs 92.3%; difference, 35.2%; 95% CI, 3.3%-73.6%), and pN1 or higher category (61.2% vs 82.6%; difference, 21.4%; 95% CI, 14.1%-56.8%). Lower RFS was associated with female sex (37.9% vs 90.9%; difference, 53.0%; 95% CI, 8.0%-97.9%), advanced T category (pT3-4, 35.3% vs 80.0%; difference, 44.7%; 95% CI, 6.4%-95.3%), lymph node yield of 20 or greater (31.4% vs 80.6%; difference, 49.2%; 95% CI, 4.9%-93.4%), and lymph node ratio of less than 4.6% (36.6% vs 84.4%; difference, 47.8%; 95% CI, 1.8%-93.1%).

Conclusions and Relevance

In this cohort study of patients with advanced OSCC, refusal of AT was associated with worse oncological outcomes. The prevalence of disease recurrence during follow-up was 34% higher in patients who refused AT than in patients who completed AT. The results from this study may assist clinicians in guiding patients who are considering refusal of or withdrawal from AT.

Effect of radiotherapy on phagocytosis percentage and index in patients with oral squamous cell carcinoma

BACKGROUND

Phagocytosis plays an important role in the fundamental process of immunity and maintains systemic tissue homeostasis. Phagocytosis function is assessed in radiotherapy to signify the prognosis of patient. Therefore, we designed a study to assess and compare the phagocytosis percentage and phagocytic index of the leucocytes in patients with oral cancer before and after radiotherapy.

MATERIALS AND METHODS

A total of 60 subjects of both genders, between 50 and 75 years old, were included in the study. The subjects were categorized into three groups: group I: oral squamous cell carcinoma (OSCC) patients before radiotherapy (n = 20), group II: OSCC patients after radiotherapy (n = 20), and group III: control (n = 20). Further, 2-mL blood samples were collected from the patients during the 1st day before radiotherapy and at the end of radiotherapy. The obtained samples were centrifuged, separated leucocytes were incubated with C. albicans, and smears were made to determine the phagocytosis percentage and phagocytic index. The obtained values were tabulated and statistically analyzed. P < 0.05 was considered to be statistically significant.

RESULTS

Phagocytosis percentage and phagocytic index of OSCC patients before radiotherapy, OSCC patients after radiotherapy, and in the control group and the difference was found to be statistically highly significant (P < 0.01).

CONCLUSION

Phagocytosis function can be determined by assessing the phagocytic index and percentage to know the effect of radiotherapy-induced systemic immune suppression and predict the prognosis of OSCC patients after radiotherapy.

Definitive Surgery after Neoadjuvant Chemotherapy for Locally Advanced Oral Cavity Cancers: Experience from a Tertiary Care Center

Mansi AgrawalVidya KonduruBackground  Oral cavity cancers require definitive surgical resection as the primary treatment, but with advanced T stage, complete resection with pathologically negative margins might be difficult to achieve. Induction chemotherapy helps achieve the balance between resection and morbidity in locally advanced technically unresectable tumors. The aim of this study was to analyze the impact of surgery in locally advanced, technically unresectable oral cavity cancers after neoadjuvant chemotherapy (NACT). Materials and Methods  A retrospective analysis of patients with borderline resectable, locally advanced oral cavity cancers who were given NACT between February 2017 and December 2021 was conducted. Data regarding clinical and pathological characteristics, NACT, surgery, adjuvant therapy, and recurrences was analyzed. Results  Of the 69 patients in the study, 69.6% had tongue cancer, rest were gingivobuccal complex cancers. All tumors were resected based on the post-NACT tumor volume and clear margins were achieved in 42% of cases. About 85.4% of the tongue cancers required a lesser resection than anticipated, thereby following the concept of organ and functional preservation post-NACT as proposed by Licitra et al. About 30.4% had ypT0 and 17.4% had ypN0. Recurrence and survival rates noted in our study were comparable to those reported in literature. Lymph node density of more than or equal to 0.07 was found in all recurrent cases. Conclusions  Induction chemotherapy offers a chance of achieving adequate surgical resection while reducing morbidity and improving functional outcomes for patients with technically unresectable oral cavity cancers. Nodal disease may not respond to chemotherapy as well as the primary tumor. There is a need for comprehensive evaluation of prognostic factors, which could help identify the patients who will most benefit with NACT.

Therapeutic strategy for oncovirus-mediated oral cancer: A comprehensive review

Oral cancer is a neoplastic disorder of the oral cavities, including the lips, tongue, buccal mucosa, and lower and upper gums. Oral cancer assessment entails a multistep process that requires deep knowledge of the molecular networks involved in its progression and development. Preventive measures including public awareness of risk factors and improving public behaviors are necessary, and screening techniques should be encouraged to enable early detection of malignant lesions. Herpes simplex virus (HSV), human papillomavirus (HPV), Epstein-Barr virus (EBV), and Kaposi sarcoma-associated herpesvirus (KSHV) are associated with other premalignant and carcinogenic conditions leading to oral cancer. Oncogenic viruses induce chromosomal rearrangements; activate signal transduction pathways via growth factor receptors, cytoplasmic protein kinases, and DNA binding transcription factors; modulate cell cycle proteins, and inhibit apoptotic pathways. In this review, we present an up-to-date overview on the use of nanomaterials for regulating viral proteins and oral cancer as well as the role of phytocompounds on oral cancer. The targets linking oncoviral proteins and oral carcinogenesis were also discussed.

Identification of an endoplasmic reticulum stress-related prognostic risk model with excellent prognostic and clinical value in oral squamous cell carcinoma

BACKGROUND

Recently, endoplasmic reticulum stress related gene (ERS) markers have performed very well in predicting the prognosis of tumor patients.

METHODS

The differentially expressed genes in Oral squamous cell carcinoma (OSCC) were obtained from TCGA and GTEx database. Three prognosis-related and differentially expressed ERSs were screened out by Least Absolute Selection and Shrinkage Operator (Lasso) regression to construct a prognostic risk model. Receiver Operating Characteristic Curve (ROC), riskplots and survival curves were used to verify the model's accuracy in predicting prognosis. Multi-omics analysis of immune infiltration, gene mutation, and stem cell characteristics were performed to explore the possible mechanism of OSCC. Finally, we discussed the model's clinical application value from the perspective of drug sensitivity.

RESULTS

Three genes used in the model (IBSP, RDM1, RBP4) were identified as prognostic risk factors. Bioinformatics analysis, tissue and cell experiments have fully verified the abnormal expression of these three genes in OSCC. Multiple validation methods and internal and external datasets confirmed the model's excellent performance in predicting and discriminating prognosis. Cox regression analysis identified risk score as an independent predictor of prognosis. Multi-omics analysis found strong correlations between risk scores and immune cells, cell stemness index, and tumor mutational burden (TMB). It was also observed that the risk score was closely related to the half maximal inhibitory concentration of docetaxel, gefitinib and erlotinib. The excellent performance of the nomogram has been verified by various means.

CONCLUSION

A prognostic model with high clinical application value was constructed. Immune cells, cellular stemness, and TMB may be involved in the progression of OSCC.

Carcinoma buccal mucosa treated with definitive hypofractionated accelerated radiotherapy: a retrospective analysis of treatment outcomes

Introduction

Oral cancer is a major public health concern in India. Both conventional and altered fractionation radiotherapy schedules have been used in curative treatment of oral cancer. This study aimed to retrospectively evaluate the clinical profile and treatment outcomes of patients with carcinoma buccal mucosa who underwent treatment with definitive hypofractionated accelerated radiotherapy.

Methods

A total of 517 patients treated from January 2011 to December 2016 were eligible for the analysis. All patients were treated with definitive hypofractionated accelerated radiotherapy schedule of 5,250 cGy in 15 fractions over 3 weeks. Survival estimates were generated using the Kaplan-Meier method.

Results

At a median follow-up of 77.4 months, 473 (91.5%) patients attained complete remission with radiation therapy. The 5-year disease-free survival (DFS) and overall survival (OS) rates were 69% and 80.5%, respectively. The 5-year OS for stage I, II, III and IVa tumours was 80.3%, 84.4%, 81.4% and 73.7%, respectively, and the DFS was 75.7%, 73.2%, 69.6% and 60.2%, respectively. Age >50 years was found to be a significant factor affecting DFS (P = 0.026) and OS (P = 0.048) in multivariate analysis. Fifty-three (10.3%) patients developed osteoradionecrosis of the mandible.

Conclusion

Excellent outcome could be achieved in less-aggressive, low-volume carcinoma of the buccal mucosa with radical accelerated hypofractionated radiotherapy. A radiotherapy schedule over a 3-week period is useful in high-volume centres.

A Targeted and pH-Responsive Nano-Graphene Oxide Nanoparticle Loaded with Doxorubicin for Synergetic Chemo-Photothermal Therapy of Oral Squamous Cell Carcinoma

Purpose

Oral squamous cell carcinoma (OSCC) is a malignant disease with serious impacts on human health and quality of life worldwide. This disease is traditionally treated through a combination of surgery, radiotherapy, and chemotherapy. However, the efficacy of traditional treatments is hindered by systemic toxicity, limited therapeutic effects, and drug resistance. Fibroblast activation protein (FAP) is a membrane-bound protease. Although FAP has limited expression in normal adult tissues, it is highly expressed in the tumor microenvironment of many solid cancers - a characteristic that makes it an ideal target for anticancer therapy. In this study, we constructed a nano-drug delivery system (NPF@DOX) targeting FAP to increase the therapeutic efficiency of synergistic chemo-photothermal therapy against OSCC.

Methods

We utilized PEGylated nano-graphene oxide (NGO) to link doxorubicin (DOX) and fluorescently-labeled, FAP-targeted peptide chains via hydrogen bonding and π-π bonding to enhance the targeting capability of NPF@DOX. The synthesis of NPF@DOX was analyzed using UV-Vis and FT-IR spectroscopy and its morphology using transmission electron microscopy (TEM). Additionally, the drug uptake efficiency in vitro, photo-thermal properties, release performance, and anti-tumor effects of NPF@DOX were evaluated and further demonstrated in vivo.

Results

Data derived from FT-IR, UV-Vis, and TEM implied successful construction of the NPF@DOX nano-drug delivery system. Confocal laser scanning microscopy images and in vivo experiments demonstrated the targeting effects of FAP on OSCC. Furthermore, NPF@DOX exhibited a high photothermal conversion efficiency (52.48%) under near-infrared radiation. The thermogenic effect of NPF@DOX simultaneously promoted local release of DOX and apoptosis based on a pH-stimulated effect. Importantly, FAP-targeted NPF@DOX in combination with PTT showed better tumor suppression performance in vivo and in vitro than did either therapy individually.

Conclusion

NPF@DOX can precisely target OSCC, and combined treatment with chemical and photothermal therapy can improve the therapeutic outcomes of OSCC. This method serves as an efficient therapeutic strategy for the development of synergistic anti-tumor research.

Polydopamine surface-modified hyperbranched polymeric nanoparticles for synergistic chemo/photothermal therapy of oral cancer

A novel drug delivery system for the treatment of oral cancer was developed using a facile polydopamine (PDA)-based surface modification and a binding mechanism linking folic acid-targeting ligands. The system was able to achieve the following objectives: loading of chemotherapeutic agents, active targeting, pH responsiveness, and prolonged in vivo blood circulation. DOX-loaded polymeric nanoparticles (DOX/H20-PLA@PDA NPs) were functionalized with amino-poly (ethylene glycol)-folic acid (H₂N-PEG-FA) after coating them with PDA to form the targeting combination, DOX/H20-PLA@PDA-PEG-FA NPs. The novel NPs exhibited drug delivery characteristics similar to DOX/H20-PLA@ PDA NPs. Meanwhile, the incorporated H₂N-PEG-FA contributed to active targeting, as illustrated in cellular uptake assays and animal studies. In vitro cytotoxicity and in vivo anti-tumor studies have shown that the novel nanoplatforms exhibit extremely effective therapeutic effects. In conclusion, the multifunctional PDA-modified H20-PLA@PDA-PEG-FA NPs offer a promising chemotherapeutic strategy to improve the treatment of oral cancer.

Matrix stiffness induces an invasive-dormant subpopulation via cGAS-STING axis in oral cancer

OBJECTIVES

Dormancy is a crucial machinery for cancer cells to survive hostile microenvironment. It is considered as the major cause of post-treatment relapse and metastases. However, its regulatory mechanism in oral squamous cell carcinoma (OSCC) remains unclear. Here we sought to decipher the impacts of matrix stiffness on OSCC-cell dormancy.

MATERIALS AND METHODS

Clinicopathological relevance of matrix stiffness in OSCC was analyzed in a 127 patients' cohort. Impacts of stiffness-related mechanical stress (MS) on OSCC-cell behaviors were investigated in vitro and in vivo. Transcriptomic profiling of MS induced dormant cells were performed, following by mechanistic investigations on MS-induced dormancy. The functional relevance of cGAS in OSCC were analyzed through a bioinformatic approach.

RESULTS

Stiffened matrix correlated with poor survival and post-surgical recurrence in OSCC. Stiffness-related MS induces a dormant subpopulation in OSCC cells, which showed increased drug resistance, enhanced tumor repopulating ability, and an unexpected upregulation of epithelial-mesenchymal transition (EMT) and invasiveness. Mechanistically, MS caused DNA damage, resulted in activation of cGAS-STING signaling. Either blocking of cGAS or STING dramatically impeded the MS-induced production of this invasive-dormant subpopulation. Moreover, cGAS was found being central to the cell-cycle regulation and correlated with poor prognosis in OSCC.

DISCUSSION

We revealed a previously unsuspected role of cGAS-STING axis in mediating the induction of an invasive-dormant subpopulation in response to mechanical cues. Our findings indicated an adaptive machinery whereby tumor cells survive and escape from harsh microenvironment. Targeting this machinery may be a potential strategy for preventing post-therapeutic recurrence and lymphatic metastasis in OSCC.

Identification of Potential Molecular Mechanisms and Prognostic Markers for Oral Squamous Cell Carcinoma: A Bioinformatics Analysis

Aims and Objectives

The goal of this study was to uncover crucial biochemical pathways, prognostic indicators, and therapeutic targets in patients with oral cancer in order to enhance therapy strategies.

Materials and Methods

Five gene expression omnibus datasets were analyzed by using bioinformatics approaches to identify differentially expressed genes (DEGs). To determine biological alterations, gene ontology (GO) and KEGG pathway analyses were implied using the identified DEGs. Hub genes were determined using protein-protein interaction (PPI) network analysis and an interactome was constructed using NetworkAnalyst. Furthermore, five hub genes were evaluated for use as prognostic markers by using the human protein atlas (HPA) and the GEPIA2.0 database. In addition, the correlations between hub-gene expression and immune cell infiltration of oral squamous cell carcinoma (OSCC) tumors were analyzed using the tWumor immune estimation resource (TIMER) database.

Results

A total of 2071 upregulated genes and 1893 downregulated genes were identified. GO and pathway analysis showed DEGs were enriched in multiple immune response terms and interaction of inflammatory cytokines. From the PPI network, five hub genes were identified that have a crucial role in OSCC. These included interferon regulatory factor 4 (IRF4), chemokine receptor 7 (CCR7), TNF receptor superfamily member 17 (TNFRSF17), CD27, and sphingosine-1-phosphate receptor 4 (S1PR4), which were predicted to be favorable prognostic markers for OSCC using HPA. Overall survival analysis revealed that low expression of the five hub genes was significantly associated with worse overall survival. Our analysis of tumor-associated immune infiltration revealed that increased IRF4 expression was positively correlated with the gene expression profiles suggestive of infiltration of all immune cell types, whereas increased CCR7 expression was negatively correlated with neutrophil infiltration. Increased expression of CD27, S1PR4, and TNFRSF17 was found to be negatively correlated with dendritic cell, M0 macrophage, and neutrophil infiltration.

Conclusion

In summary, inflammation, and the immune response play an important role in OSCC. All five hub genes were good predictors of OSCC prognosis, suggesting that they could be used as potential therapeutic targets and tumor markers.

Proteasome inhibitor MG132 enhances the sensitivity of human OSCC cells to cisplatin via a ROS/DNA damage/p53 axis

Cis-diamine-dichloroplatinum II (cisplatin, CDDP) is a key chemotherapeutic regimen in the treatment of oral squamous cell carcinoma (OSCC). However, the therapeutic efficacy of cisplatin in OSCC may be hampered by chemoresistance. Therefore, the development of novel combination therapy strategies to overcome the limitations of CDDP is of great importance. The proteasome inhibitor MG132 exhibits anti-cancer properties against various types of cancer. However, our knowledge of its anti-cancer effects in combination with CDDP in OSCC cells remains limited. In the current study, the synergetic effects of MG132 and CDDP were evaluated in the human CAL27 OSCC cell line. CAL27 cells were treated with CDDP alone or in combination with MG132. The results showed that MG132 significantly reduced cell viability in a dose-dependent manner. Additionally, cell viability was significantly reduced in CAL27 cells treated with 0.2 µM MG132 and 2 µM CDDP compared with cells treated with MG132 or CDDP alone. In addition, MG132 significantly enhanced the CDDP-induced generation of intracellular reactive oxygen species and DNA damage in OSCC cells. Furthermore, treatment with CDDP or MG132 alone notably inhibited colony formation and proliferation of OSCC cells. However, co-treatment of OSCC cells with MG132 and CDDP further hampered colony formation and proliferation compared with cells treated with either MG132 or CDDP alone. Finally, in cells co-treated with MG132 and CDDP, the expression of p53 was markedly elevated and the p53-mediated apoptotic pathway was further activated compared with cells treated with MG132 or CDDP alone, as shown by the enhanced cell apoptosis, Bax upregulation, and Bcl-2 downregulation. Overall, the results of the current study support the synergistic anti-cancer effects of a combination of MG132 and CDDP against OSCC, thus suggesting that the combination of MG132 and CDDP may be a promising therapeutic strategy for the management of OSCC.

IRAK2, an Immune and Radiation-Response Gene, Correlates with Advanced Disease Features but Predicts Higher Post-Irradiation Local Control in Non-Metastatic and Resected Oral Cancer Patients

Gene Ontology (GO) analysis can provide a comprehensive function analysis for investigating genes, allowing us to identify the potential biological roles of genes. The present study conducted GO analysis to explore the biological function of IRAK2 and performed a case analysis to define its clinical role in disease progression and mediating tumor response to RT. Methods: We performed a GO enrichment analysis on the RNA-seq data to validate radiation-induced gene expression. A total of 172 I-IVB specimens from oral squamous cell carcinoma patients were collected for clinical analysis, from which IRAK2 expression was analyzed by immunohistochemistry. This was a retrospective study conducted between IRAK2 expression and the outcomes of oral squamous cell carcinoma patients after radiotherapy treatment. We conducted Gene Ontology (GO) analysis to explore the biological function of IRAK2 and performed a case analysis to define its clinical role in mediating tumor response to radiotherapy. GO enrichment analysis to validate radiation-induced gene expression was performed. Clinically, 172 stage I-IVB resected oral cancer patients were used to validate IRAK2 expression in predicting clinical outcomes. GO enrichment analysis showed that IRAK2 is involved in 10 of the 14 most enriched GO categories for post-irradiation biological processes, focusing on stress response and immune modulation. Clinically, high IRAK2 expression was correlated with adverse disease features, including pT3-4 status (p = 0.01), advanced overall stage (p = 0.02), and positive bone invasion (p = 0.01). In patients who underwent radiotherapy, the IRAK2-high group was associated with reduced post-irradiation local recurrence (p = 0.025) compared to the IRAK2-low group. IRAK2 plays a crucial role in the radiation-induced response. Patients with high IRAK2 expression demonstrated more advanced disease features but predicted higher post-irradiation local control in a clinical setting. These findings support IRAK2 as a potential predictive biomarker for radiotherapy response in non-metastatic and resected oral cancer patients.

Oral health related quality of life of oral cancer patients treated with radiotherapy alone or with chemotherapy in a tertiary referral centre in Sri Lanka

BACKGROUND

Oral cancer is the number one cancer among males in Sri Lanka. Radiotherapy is a common treatment modality for oral cancer, but this can affect oral health related quality of life (OHRQOL). This study assessed the OHRQOL and its changes from baseline to the last week of radiotherapy and three months post radiotherapy among oral cancer patients who received this treatment alone or with chemotherapy.

METHODS

A prospective longitudinal study was conducted among 90 oral cancer patients awaiting for radiotherapy alone or with chemotherapy. The modified Sinhala version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Oral Health Module (EORTC QLQ-OH15) was used to gather data related to OHRQOL before radiotherapy. Socio-demographic and clinical data were also recorded. The same cohort of patients were followed up and assessed their OHRQOL during the last week of radiotherapy and three months post radiotherapy. The Modified EORTC QLQ-OH15 assesses the OHRQOL under three domains namely 'Eating problem', 'Gum and speech problem' and 'Soreness', and one item named as 'Teeth'.

RESULTS

The majority of the sample (88%) was males. The anterior two-thirds of the tongue (40%) and buccal mucosa (22%) were the most common sites. The median scores of 'Eating problem' domain at baseline, last week of radiotherapy and three months post radiotherapy were 20 (IQR = 6.7-33.3), 100 (IQR = 86.9-100.0) and 66.7 (IQR = 46.7-93.3) respectively. 'Gum and speech problem' was higher during last week of radiotherapy (median, 50.0, IQR, 25.0-58.3) than three months post radiotherapy (median, 8.3, IQR, 0.0-33.3). The changes of OHRQOL between the time frames were statistically significant (p < 0.05). Baseline OHRQOL in relation to 'Gum and speech problem' domain and 'Teeth' item was identified as an influential factor for OHRQOL during last week of radiotherapy.

CONCLUSION

The OHRQOL of oral cancer patients who received radiotherapy alone or with chemotherapy had deteriorated from the baseline level to the last week of radiotherapy but then improved at three months post radiotherapy. The OHRQOL however did not return to the baseline level three months post radiotherapy. OHRQOL during the last week of radiotherapy was influenced by the OHRQOL at baseline, civil status and sites of metastasis.

Network-Based Method to Investigate the Promoted Cell Apoptosis Mechanisms of Oridonin in OSCC through the RNA-Transcriptome

The morbidity of oral cancer is high in the world. Oridonin is a traditional Chinese medicine that can effectively inhibit oral squamous cell carcinoma (OSCC) growth, but its mechanism remains unclear. Our previous data showed that oridonin inhibited CAL-27 cell proliferation and promoted apoptosis. Herein, we explored the mechanism and target of oridonin in human OSCC through RNA sequencing and integration of multiple bioinformatics analysis strategies. Differences in gene expression can be analyzed with RNA sequencing. Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), gene set enrichment analysis (GSEA), Disease Ontology (DO), and other enrichment analyses were used to evaluate differentially expressed genes (DEGs). Protein–protein interaction (PPI) networks were built via the STRING database. It was found that tumor necrosis factor (TNF) signaling pathway, cytokine–cytokine receptor interaction, and nuclear factor-kappa B (NF-kappaB) signaling pathway were associated with the therapeutic effects of oridonin in OSCC. Three key genes (BIRC3, TNFSF10, and BCL6) were found to associate with cell apoptosis in OSCC cells treated with oridonin. Quantitative PCR assays verified the expression of apoptosis-related DEGs: TNFSF10, BIRC3, AIFM2, BCL6, BCL2L2, and Bax. Western blots were employed for verifying proteins expression associated with DEGs: cleaved caspase 3, Bax, Bcl-w, anti-cIAP2, and anti-TRAIL. In conclusion, our findings reveal the molecular pathways and targets by which oridonin can treat and induce cytotoxic effects in OSCC: by affecting the signaling including TNF, NF-κB, and cytokine-cytokine receptor interaction and by regulating the key gene BIRC3, TNFSF10, and BCL6. It should be noted that further clinical trial validation is very necessary. Combined with current research trends, our existing research may provide innovative research drugs for the treatment of OSCC.

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.

Clinicopathological characteristics, treatment and prognosis of oral adenocarcinoma: a population-based study

OBJECTIVES

The aim of this study was to identify clinicopathologic features, treatment and prognosis of oral adenocarcinoma (OADC).

STUDY DESIGN

Retrospective cohort analysis.

SETTING

National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program.

METHODS

Patients diagnosed with OADC between 2000 to 2018 were identified from the SEER database. Overall survival (OS) and disease-specific survival (DSS) were assessed using Kaplan-Meier analyses and Cox regression models.

RESULTS

There were 924 OADC and 37,500 oral squamous cell carcinoma (OSCC) patients identified. Patients with OADC were more significantly associated with younger age, female gender, well differentiation and early AJCC Clinical stage. The study revealed that patients with OADC had better 10-year OS and DSS than those with OSCC (OS: 69.3% vs 40.8%, P < 0.001; DSS: 83.6% vs 53.3%, P < 0.001). The survival advantage still persisted in multivariable analyses (OS: hazard ratio [HR] = 0.427, P < 0.001; DSS: HR = 0.320, P < 0.001). For OADC, multivariable analysis showed that advanced age, stage, and histologic grade were associated with worse OS and DSS, and surgery was associated with better OS and DSS.

CONCLUSIONS

OADC has a significantly better prognosis than OSCC, with better differentiation, and more early stage. Surgery was the preferred treatment, for patients with lymph node metastasis, radiotherapy may afford a survival benefit.

The Debate between the Human Microbiota and Immune System in Treating Aerodigestive and Digestive Tract Cancers: A Review

The human microbiota comprises a group of microorganisms co-existing in the human body. Unbalanced microbiota homeostasis may impact metabolic and immune system regulation, shrinking the edge between health and disease. Recently, the microbiota has been considered a prominent extrinsic/intrinsic element of cancer development and a promising milestone in the modulation of conventional cancer treatments. Particularly, the oral cavity represents a yin-and-yang target site for microorganisms that can promote human health or contribute to oral cancer development, such as Fusobacterium nucleatum. Moreover, Helicobacter pylori has also been implicated in esophageal and stomach cancers, and decreased butyrate-producing bacteria, such as Lachnospiraceae spp. and Ruminococcaceae, have demonstrated a protective role in the development of colorectal cancer. Interestingly, prebiotics, e.g., polyphenols, probiotics (Faecalibacterium, Bifidobacterium, Lactobacillus, and Burkholderia), postbiotics (inosine, butyrate, and propionate), and innovative nanomedicines can modulate antitumor immunity, circumventing resistance to conventional treatments and could complement existing therapies. Therefore, this manuscript delivers a holistic perspective on the interaction between human microbiota and cancer development and treatment, particularly in aerodigestive and digestive cancers, focusing on applying prebiotics, probiotics, and nanomedicines to overcome some challenges in treating cancer.

Melatonin: Emerging Player in the Management of Oral Cancer

Oral cancer (OC) has emerged as a major medical and social issue in many industrialized nations due to the high death rate. It is becoming increasingly common in people under the age of 45, although the underlying causes and mechanisms of this increase remain unclear. Melatonin, as a pleiotropic hormone, plays a pivotal role in a wide variety of cellular and physiological functions. Mounting evidence supports melatonin's ability to modify/influence oral carcinogenesis, help in the reduction of the incidence of OC, and increase chemo- and radiosensitivity. Despite its potential anti-carcinogenic effects, the precise function of melatonin in the management of OC is not well understood. This review summarizes the current knowledge regarding melatonin function in anti-carcinogenesis mechanisms for OC. In addition, clinical assessment and the potential therapeutic utility of melatonin in OC are discussed. This review will provide a basis for researchers to create new melatonin-based personalized medicines for treating and preventing OC.

Conventional Therapies of Oral Cancers: Highlights on Chemotherapeutic Agents and Radiotherapy, Their Adverse Effects, and the Cost Burden of Conventional Therapies

Oral cancer (OC) is increasing worldwide, and it is mostly present to clinic in the late-stage of disease. Cancer of the lips, tongue, hard palate, upper and lower gingiva, buccal mucosa, and retromolar trigone are all included in the category of oral cavity cancer. Disease symptomatology and pathological grading decides the course of treatment. Several treatment modalities either alone in combinations may be utilized for oral squamous cell carcinoma (OSCC), including surgery, radiotherapy (external beam radiotherapy/brachytherapy), and adjuvant systemic therapy (chemotherapy or immunotherapy). Cancer patients also face a greater risk of oral side effects from chemotherapy, such as slowed tissue healing, bone, and salivary gland damage and disintegration, and disruption of the normal bacterial balance in the mouth. Consequently, the economic burden of the salivary gland, oral cavity, and oropharyngeal cancers must be also known for budget allocation, designing different programs and management strategies targeting oral cancers by any healthcare institutes. This article provides a summary of the most recent research that supports the use of chemotherapy for patients with advanced illness both alone and in conjunction with radiation including its adverse events and cost burden for oral cancers.

Novel Strategies for the Bioavailability Augmentation and Efficacy Improvement of Natural Products in Oral Cancer

Oral cancer is emerging as a major cause of mortality globally. Oral cancer occupies a significant proportion of the head and neck, including the cheeks, tongue, and oral cavity. Conventional methods in the treatment of cancer involve surgery, radiotherapy, and immunotherapy, and these have not proven to completely eradicate cancerous cells, may lead to the reoccurrence of oral cancer, and possess numerous adverse side effects. Advancements in novel drug delivery approaches have gained popularity in cancer management with an increase in the number of cases associated with oral cancer. Natural products are potent sources for drug discovery, especially for anticancer drugs. Natural product delivery has major challenges due to its low solubility, poor absorption, inappropriate size, instability, poor permeation, and first-pass metabolism. Therefore, it is of prime importance to investigate novel treatment approaches for the delivery of bioactive natural products. Nanotechnology is an advanced method of delivering cancer therapy with minimal damage to normal cells while targeting cancer cells. Therefore, the present review elaborates on the advancements in novel strategies for natural product delivery that lead to the significant enhancement of bioavailability, in vivo activity, and fewer adverse events for the prevention and treatment of oral cancer. Various approaches to accomplish the desired results involve size reduction, surface property modification, and polymer attachment, which collectively result in the higher stability of the formulation.

Role Played by Paraoxonase-2 Enzyme in Cell Viability, Proliferation and Sensitivity to Chemotherapy of Oral Squamous Cell Carcinoma Cell Lines

Oral squamous cell carcinoma represents the most aggressive and frequent form of head and neck cancer. Due to drug resistance, the 5-year survival rate of patients with advanced disease is less than 50%. In order to identify molecular targets for effective oral cancer treatment, we focused on paraoxonase-2 enzyme. Indeed, based on data previously obtained from preliminary immunohistochemistry and Western blot analyses performed on tissue specimens, the enzyme was found to be upregulated in tumor compared with normal oral mucosa. Therefore, paraoxonase-2 gene silencing was achieved in HSC-3 and HOC621 oral cancer cell lines, and the effect on cell proliferation, viability, apoptosis induction and sensitivity to cisplatin and 5-fluorouracil treatment was evaluated. Fourier Transform InfraRed Microspectroscopy analyzed alterations of cellular macromolecules upon treatment. Enzyme level and cell proliferation were also determined in cisplatin-resistant clones obtained from HOC621 cell line, as well as in parental cells. Reported data showed that paraoxonase-2 knockdown led to a reduction of cell proliferation and viability, as well as to an enhancement of sensitivity to cisplatin, together with the activation of apoptosis pathway. Spectroscopical data demonstrated that, under treatment with cisplatin, oxidative damage exerted on lipids and proteins was markedly more evident in cells down-regulating paraoxonase-2 compared to controls. Interestingly, enzyme expression, as well as cell proliferation were significantly higher in cisplatin-resistant compared with control HOC621 cells. Taken together these results seem to candidate the enzyme as a promising target for molecular treatment of this neoplasm.

Real-Time Monitoring of the Cytotoxic and Antimetastatic Properties of Cannabidiol in Human Oral Squamous Cell Carcinoma Cells Using Electric Cell-Substrate Impedance Sensing

Cannabidiol (CBD) is an active natural compound that is extracted from Cannabis sativa. Previous studies show that CBD is a nonpsychotropic compound with significant anticancer effects. This study determines its cytotoxic effect on oral cancer cells and OEC-M1 cells and compares the outcomes with a chemotherapeutic drug, cisplatin. This study has investigated the effect of CBD on the viability, apoptosis, morphology, and migration of OEC-M1 cells. Electric cell-substrate impedance sensing (ECIS) is used to measure the change in cell impedance for cells that are treated with a series concentration of CBD for 24 h. AlamarBlue and annexin V/7-AAD staining assays show that CBD has a cytotoxic effect on cell viability and induces cell apoptosis. ECIS analysis shows that CBD decreases the overall resistance and morphological parameters at 4 kHz in a concentration-dependent manner. There is a significant reduction in the wound-healing recovery rate for cells that are treated with 30 μM CBD. This study demonstrates that ECIS can be used for in vitro screening of new chemotherapy and is more sensitive, functional, and comprehensive than traditional biochemical assays. CBD also increases cytotoxicity on cell survival and the migration of oral cancer cells, so it may be a therapeutic drug for oral cancer.

Combined Treatment (Ultraviolet-C/Physapruin A) Enhances Antiproliferation and Oxidative-Stress-Associated Mechanism in Oral Cancer Cells

Physapruin A (PHA), a Physalis peruviana-derived withanolide, exhibits antiproliferation activity against oral and breast cancer cells. However, its potential antitumor effects in combined treatments remain unclear. This investigation focused on evaluating the impact of the combined treatment of ultraviolet-C with PHA (UVC/PHA) on the proliferation of oral cancer cells. The UVC-caused antiproliferation was enhanced by combination with PHA in oral cancer (Ca9-22 and CAL 27) but not normal cells (SG), as evidenced by ATP detection, compared with UVC or PHA alone. UVC/PHA showed a greater extent of subG1 increase, G2/M arrest, annexin-V-assessed apoptosis, caspase 3/7 activation, and reactive oxygen species (ROS) in the UVC or PHA treatment of oral cancer compared to normal cells. Moreover, the mitochondrial functions, such as mitochondrial superoxide bursts and mitochondrial membrane potential destruction, of oral cancer cells were also enhanced by UVC/PHA compared to UVC or PHA alone. These oxidative stresses triggered γH2AX and 8-hydroxyl-2'-deoxyguanosine-assessed DNA damage to a greater extent under UVC/PHA treatment than under UVC or PHA treatment alone. The ROS inhibitor N-acetylcysteine reversed all these UVC/PHA-promoted changes. In conclusion, UVC/PHA is a promising strategy for decreasing the proliferation of oral cancer cells but shows no inhibitory effect on normal cells.

Tumor microenvironment and immunotherapy of oral cancer

Oral cancer is one of the most common malignant tumors of the head and neck, not only affects the appearance, but also affects eating and even endangers life. The clinical treatments of oral cancer mainly include surgery, radiotherapy, and chemotherapy. However, unsatisfactory therapeutic effect and toxic side effects are still the main problems in clinical treatment. Tumor microenvironment (TME) is not only closely related to the occurrence, growth, and metastasis of tumor but also works in the diagnosis, prevention, and treatment of tumor and prognosis. Future studies should continue to investigate the relationship of TME and oral cancer therapy. This purpose of this review was to analyze the characteristics of oral cancer microenvironment, summarize the traditional oral cancer therapy and immunotherapy strategies, and finally prospect the development prospects of oral cancer immunotherapy. Immunotherapy targeting tumor microenvironment is expected to provide a new strategy for clinical treatment of oral cancer.

CMTM6 attenuates cisplatin-induced cell death in OSCC by regulating AKT/c-Myc-driven ribosome biogenesis

CMTM6, a type 3 transmembrane protein, is known to stabilize the expression of programmed cell death ligand 1 (PD-L1) and hence facilitates the immune evasion of tumor cells. Recently, we demonstrated that CMTM6 is a major driver of cisplatin resistance in oral squamous cell carcinomas (OSCC). However, the detailed mechanism of how CMTM6 rewires cisplatin resistance in OSCC is yet to be explored. RNA sequencing analysis of cisplatin-resistant OSCC lines stably expressing Nt shRNA and CMTM6 shRNA revealed that CMTM6 might be a potential regulator of the ribosome biogenesis network. Knocking down CMTM6 significantly inhibited transcription of 47S precursor rRNA and hindered the nucleolar structure, indicating reduced ribosome biogenesis. When CMTM6 was ectopically over-expressed in CMTM6KD cells, almost all ribosomal machinery components were rescued. Mechanistically, CMTM6 induced the expression of C-Myc, which promotes RNA polymerase I mediated rDNA transcription. In addition to this, CMTM6 was also found to regulate the AKT-mTORC1-dependent ribosome biogenesis and protein synthesis in cisplatin-resistant lines. The nude mice and zebrafish xenograft experiments indicate that blocking ribosome synthesis either by genetic inhibitor (CMTM6KD) or pharmacological inhibitor (CX-5461) significantly restores cisplatin-mediated cell death in chemoresistant OSCC. Overall, our study suggests that CMTM6 is a major regulator of the ribosome biogenesis network and targeting the ribosome biogenesis network is a viable target to overcome chemoresistance in OSCC. The novel combination of CX-5461 and cisplatin deserves further clinical investigation in advanced OSCC.

Stem cell membrane-coated abiotic nanomaterials for biomedical applications

Nanoscale materials have been extensively employed for diagnostic and therapeutic purposes. However, the developed nanosystems still suffer from some limitations, namely the rapid elimination by the immune system, lack of targeting to specific cells, and insufficient biocompatibility. Therefore, novel strategies based upon a biomimetic approach have received attention to improving the pharmacokinetics and safety profile of nanosystems. One promising strategy is the application of a biomimetic coating consisting of cell membranes derived from different cell types onto nanoparticle cores. Stem cells have been investigated to develop targeted nanodevices owing to their excellent intrinsic tissue-specific homing features, protecting them from the immune system to reach the sites of inflammation. This targeting ability is conferred by a surface repertoire of stem cell-associated biomolecules. Such nanoscopical materials offer sustained circulation and boosted drug accumulation at target sites, augmenting therapeutic efficacy and safety. Additionally, the coating of nanoparticles with cell membranes acts as a camouflage mechanism to increase their circulation time. The current review explores the particular features of stem cell membrane coating as multifunctional biomimetic surface functionalization agents to camouflage nanoparticle cores. Biomedical applications of engineered stem cell membrane-coated nanoparticles, challenges in clinical translation, and their future prospects are addressed.

Anti-Cancer Activity of the Combinational Treatment of Noozone Cold Plasma with p-FAK Antibody-Conjugated Gold Nanoparticles in OSCC Xenograft Mice

Oral squamous cell cancer (OSCC) is the most common type of oral cancer (about 80–90% of cases) and various research is being done to cure the disease. This paper aims to verify whether treatment with no-ozone cold plasma (NCP), which is designed for safe usage of the plasma on oral cavities, in combination with gold nanoparticles conjugated with p-FAK antibody (p-FAK/GNP) can trigger the selective and instant killing of SCC-25 cells both in vitro and in vivo. When SCC25 and HaCaT cells are exposed to p-FAK/GNP+NCP, the instant cell death was observed only in SCC25 cells. Such p-FAK/GNP+NCP-mediated cell death was observed only when NCP was directly treated on SCC25 harboring p-FAK/GNP. During NCP treatment, the removal of charged particles from NCP using grounded electric mesh radically decreased the p-FAK/GNP+NCP-mediated cell death. This p-FAK/GNP+NCP-mediated selective cell death of OSCC was also observed in mice xenograft models using SCC25 cells. The mere treatment of p-FAK/GNP and NCP on the xenograft tumor slowly decreased the size of the tumor, and only about 50% of the tumor remained at the end of the experiment. On the other hand, 1 week of p-FAK/GNP+NCP treatment was enough to reduce half of the tumor size, and most of tumor tissue had vanished at the end. An analysis of isolated tissues showed that in the case of individual treatment with p-FAK/GNP or NCP, the cancer cell population was reduced due to apoptotic cell death. However, in the case of p-FAK/GNP+NCP, apoptotic cell death was unobserved, and most tissues were composed of collagen. Thus, this paper suggests the possibility of p-FAK/GNP+NCP as a new method for treating OSCC.