Histopathologic prognostic indices in tongue squamous cell carcinoma

Risk Factors of Oral Squamous Cell Carcinoma with Special Emphasis on Areca Nut Usage and Its Association with Clinicopathological Parameters and Recurrence

Introduction

Oral squamous cell carcinoma (OSCC) is the most prevalent type of head and neck cancer and is associated with high mortality, particularly in Southeast Asian countries. Areca nut usage, smoking, and alcohol consumption are the most common risk factors for OSCC. Areca nut chewing is highly prevalent in Pakistan and has been attributed to an increase in OSCC cases. This study aimed to determine the association between areca nut usage and various clinicopathological features of OSCC and further evaluate the association of clinicopathological parameters of OSCC with tumor recurrence.

Materials and Methods

The study was conducted using the data of 228 patients with OSCC resected at Liaquat National Hospital, Karachi, Pakistan, over 5 years between 2018 and 2022. Clinicopathological data were collected from hospital archives, and associations between various risk factors and clinicopathological parameters were determined.

Results

Males were more commonly affected (77.2%), and the most common age group was <50 years (54.4%). Areca nut usage was reported in 59.6% of cases, and the buccal mucosa was the most common site (62.7%). Areca nut usage was significantly associated with male gender, greater tumor size, greater depth of invasion (DOI), higher tumor stage, nodal stage, presence of perineural invasion (PNI), and recurrence. In addition, multivariate analysis revealed that OSCC recurrence was significantly associated with older age, larger tumor size and DOI, nodal metastasis, and areca nut usage.

Conclusion

Areca nut-related OSCCs were associated with poor prognosis and recurrence in our study population. Furthermore, OSCC recurrence was associated with various clinicopathological parameters, such as larger tumor size, a higher DOI, and nodal metastasis.

Experimental Study: The Development of a Novel Treatment for Chemotherapy-Resistant Tongue Cancer with the Inhibition of the Pathological Periostin Splicing Variant 1-2 with Exon 21

Tongue squamous cell carcinoma (TSCC) occurs frequently in the oral cavity, and because of its high proliferative and metastatic potential, it is necessary to develop a novel treatment for it. We have reported the importance of the inhibition of the periostin (POSTN) pathological splicing variant, including exon 21 (PN1-2), in various malignancies, but its influence is unclear in tongue cancer. In this study, we investigated the potential of POSTN exon 21-specific neutralizing antibody (PN21-Ab) as a novel treatment for TSCC. Human PN2 was transfected into the human TSCC (HSC-3) and cultured under stress, and PN2 was found to increase cell viability. PN2 induced chemotherapy resistance in HSC-3 via the phosphorylation of the cell survival signal Akt. In tissues from human TSCC and primary tumors of an HSC-3 xenograft model, PN1-2 was expressed in the tumor stroma, mainly from fibroblasts. The intensity of PN1-2 mRNA expression was positively correlated with malignancy. In the HSC-3 xenograft model, CDDP and PN21-Ab promoted CDPP's inhibition of tumor growth. These results suggest that POSTN exon 21 may be a biomarker for tongue cancer and that PN21-Ab may be a novel treatment for chemotherapy-resistant tongue cancer. The treatment points towards important innovations for TSCC, but many more studies are needed to extrapolate the results.

WAVE3 Facilitates the Tumorigenesis and Metastasis of Tongue Squamous Cell Carcinoma via EMT

Wiskott-Aldrich syndrome protein family verprolin-homologous domain-containing protein 3 (WAVE3) is reported as an oncogene regulating cell proliferation and motility in multiple malignancies, while its role in tongue squamous cell carcinoma (TSCC) remains unknown. This study aimed to explore the expression and mechanism of WAVE3 in TSCC. We enrolled 64 TSCC patients admitted between June 2013 and February 2014 and collected their cancerous and adjacent normal tissues to determine WAVE3 expression by immunohistochemistry. The correlation of WAVE3 expression with TSCC patients' pathological characteristics was analyzed. Then, a 7-year follow-up was conducted to observe the value of WAVE3 in evaluating patient outcomes. In addition, human TSCC SCC9, SCC25, and CAL27 cells were purchased and detected by Cell Counting Kit-8 (CCK-8), Transwell, and scratch-wound assays for their proliferation, invasion, and migration capacities, while real-time quantitative PCR (qRT-PCR) and Western blotting were utilized to quantify WAVE3 and epithelial-mesenchymal transition (EMT)-related protein expression, respectively. The most active cell lines were selected to be infected with lentiviral vectors that silenced WAVE3 (named WAVE3-sh group) and overexpressed WAVE3 cDNA (named WAVE3-OE group) to observe the impacts of interfering WAVE3 expression on TSCC cell biological behavior. The positive expression of WAVE3 in TSCC tissue was found to be obviously enhanced and predominantly located in the cytoplasm. In addition, close correlations were identified between WAVE3 and T staging, clinical staging, lymphatic metastasis, distant metastasis, and differentiation degree (P < 0.05). Increased WAVE3 expression predicted an elevated risk of death, as indicated by the follow-up analysis (P < 0.05). SCC9 was selected for subsequent experiments among various TSCC cell lines studied because it showed the most potent ability to proliferate, invade, and migrate (P < 0.05). Silencing WAVE3 expression in SCC9 cells decreased cell proliferation, invasion, migration, and EMT-related protein expression (P < 0.05), while increasing WAVE3 expression promoted SCC9 viability. WAVE3, which was highly expressed in TSCC, promoted EMT in tumor cells and accelerated their proliferation, invasion, and migration, which might provide a new theoretical basis for molecular targeted therapy of TSCC in the future.

The Depth of Invasion and Level IV Cervical Node Metastasis in Patients with Clinically N0 Tongue Cancer

BACKGROUND

The accurate indication for level IV dissection is crucial for preventing complications such as phrenic nerve damage and chylous fistulas in clinically N0 tongue cancer. Although the depth of invasion is an established independent risk factor for occult lymph node metastasis in tongue cancer, its relationship with level IV metastasis has not been evaluated. This study investigated the relationship between the depth of invasion and level IV nodal metastasis in clinically N0 tongue cancer.

METHODS

We retrospectively investigated clinical N0 patients who underwent glossectomy and level I-IV neck dissection. We examined lymph node metastasis, risk factors, and the relationship between depth of invasion and metastasis.

RESULTS

Our study included 58 patients, and no patient had isolated level IV metastasis. Additionally, there was no level IV metastasis in well-differentiated tumors. Tumor size, depth of invasion, differentiation, and perineural invasion were significantly associated with level IV neck metastasis. We found a critical tumor size of 2.5 cm and depth of invasion of 8 mm for level IV neck metastasis.

CONCLUSION

Based on our findings, we recommend that level IV dissection should be considered for poorly differentiated tumors, tumors greater than 2.5 cm in size, and those deeper than 8 mm. This study highlights the importance of depth of invasion as a prognostic factor for predicting level IV metastasis and suggests that our findings can be used to prevent unnecessary level IV dissections that may lead to complications in tongue cancer surgery.

Integrating DOI in T classification improves the predictive performance of laryngeal cancer staging

It has been recognized that depth of invasion (DOI) is closely associated with patient survival for most types of cancer. The purpose of this study was to determine the DOI optimal cutoff value and its prognostic value in laryngeal squamous carcinoma (LSCC). Most importantly, we evaluated the prognostic performance of five candidate modified T-classification models in patients with LSCC. LSCC patients from Harbin Medical University Cancer Hospital and Chinese Academy of Medical Sciences Cancer Hospital were divided into training group (n = 412) and validation group (n = 147). The primary outcomes were overall survival (OS) and relapse-free survival (RFS), and the effect of DOI on prognosis was analyzed using a multivariable regression model. We identified the optimal model based on its simplicity, goodness of fit and Harrell's consistency index. Further independent testing was performed on the external validation queue. The nomograms was constructed to predict an individual's OS rate at one, three, and five years. In multivariate analysis, we found significant associations between DOI and OS (Depth of Medium-risk invasion HR, 2.631; P < .001. Depth of high-risk invasion: HR, 5.287; P < .001) and RFS (Depth of high-risk invasion: HR, 1.937; P = .016). Model 4 outperformed the American Joint Committee on Cancer (AJCC) staging system based on a low Akaike information criterion score, improvement in the concordance index, and Kaplan-Meier curves. Inclusion of DOI in the current AJCC staging system can improve the differentiation of T classification in LSCC patients.

Margin distance in oral tongue cancer surgery: A systematic review of survival and recurrence outcomes

The status of resection margins is a proxy for the completeness of resection in oral tongue cancer surgery and is therefore a useful predictor for post-operative prognosis. Historically, a margin distance of 5 mm or greater has been deemed a negative margin and is believed to yield a benefit in terms of control and survival. To summarize the literature more completely on this topic, we conducted a systematic review that examines radial margin distance and its relationship to disease control and survival in oral tongue cancer. Our review includes 34 studies which reported survival and/or recurrence outcomes for oral tongue cancer patients based on margin status. Most studies reported outcomes for the 5 mm margin, while the minority utilized other margin cutoffs. For the 5 mm cutoff, outcomes were generally favorable regarding survival and recurrence outcomes. Nonetheless, studies using 4 mm, 3.3 mm, and 10 mm cutoffs also found favorable survival and recurrence outcomes; however, these are a minority of the included studies.

Brucea javanica oil inhibits tongue squamous cell invasion and metastasis by regulating miR-138-EZH2 pathway

Tongue squamous cell carcinoma (TSCC) is one of the most common malignant tumors of head and neck. Its incidence is on the rise, and the proportion of young patients is gradually increasing, which is prone to tumor recurrence and metastasis. At present, there is no effective method to completely treat TSCC. Studies have shown that brucea javanica oil (BJO) has good antitumor activity against lung cancer and gastrointestinal tumors, but its therapeutic effect on TSCC is not clear. We have previously confirmed that oleic acid, the main component of BJO, can induce apoptosis of TSCC and reduce its invasion and metastasis ability. However, the anticancer effect and mechanism of BJO in TSCC remain unclear. In order to further explore the effects of BJO on the biological characteristics of TSCC cells, we studied the effects of different concentrations of BJO on the migration, invasion ability and epithelial mesenchymal transition (EMT) progression of TSCC cells and the possible mechanisms through in vitro experiments. We found that BJO could inhibit the invasion and metastasis of TSCC and up-regulate miR-138. After BJO treatment, the expression of E-cad was significantly increased, while the expression of EZH2, Slug, p-ERK1/2 and Vimentin was significantly decreased. EZH2 is a miR-138 target gene involved in TSCC. BJO inhibits TSCC invasion and metastasis by regulating the miR-138-EZH2 pathway. In vivo experiments have also well demonstrated the targeting effect of this pathway. This study provides a new therapeutic strategy for the treatment of TSCC.

Accuracy of magnetic resonance imaging in the assessment of depth of invasion in tongue carcinoma: A systematic review and meta-analysis

Tongue carcinoma constitutes 10.4-46.9% of all oral squamous cell carcinomas (OSCCs) and is notoriously known for invading tissues deeper than the evident gross margins. The deeper the tumor invades, the higher are its chances of future morbidity and mortality due to extensive neck dissection and risk of recurrence. Magnetic resonance imaging (MRI) is a noninvasive diagnostic aid used for measuring a preoperative tumor's depth of invasion (DOI) as it can efficiently outline soft tissue tumors from adjacent normal tissue. To assess various MRI modalities used in measuring DOI in tongue carcinoma and their reliability compared with other DOI measuring modalities. The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (CRD42022330866), and the following Preferred Reporting Items for a Systematic Review and Meta-Analysis (PRISMA) Diagnostic Test Accuracy guidelines were performed. PubMed electronic database was searched using a combination of keywords for relevant articles in the English language since 2016. Critical appraisal was carried out using the Quality Assessment of Diagnostic Accuracy Studies-Comparative (QUADAS-C) risk-of-bias (RoB) assessment tool. A weighted mean difference (WMD) was calculated between MRI and histopathological DOI along with pooled correlation and subgroup analysis, where possible. A total of 795 records were retrieved of which 17 were included in the final review with 13 included for meta-analysis. A high RoB was found for most studies for all parameters except flow and timing. WMD showed a statistically significant MRI overestimation of 1.90 mm compared with histopathology. Subgroup analysis showed the 1.5 Tesla machine to be superior to the 3.0 Tesla machine, while imaging sequence subgroup analysis could not be performed. MRI is a viable preoperative DOI measurement modality that can help in efficient treatment planning to decrease surgical morbidity and mortality.

Prognostic impact of lymphovascular and perineural invasion in squamous cell carcinoma of the tongue

This study aimed to investigate the prognostic impact of lymphovascular and perineural invasions in patients with squamous cell carcinoma of the tongue who received surgery-based treatment at our institution between January 2013 and December 2020. Patients were divided into four groups based on the presence of perineural (P-/P +) and lymphovascular invasions (V-/V +): P-V-, P-V + , P + V-, and P + V + . Log-rank and Cox proportional hazard models were used to evaluate the association between perineural /lymphovascular invasion and overall survival (OS). Altogether, 127 patients were included, and 95 (74.8%), 8 (6.3%), 18 (14.2%), and 6 (4.7%) cases were classified as P-V-, P-V + , P + V-, and P + V + , respectively. Pathologic N stage (pN stage), tumor stage, histological grade, lymphovascular invasion, perineural invasion, and postoperative radiotherapy were significantly associated with OS (p < 0.05). OS was significantly different among the four groups (p < 0.05). Significant between-group differences in OS were detected for node-positive (p < 0.05) and stage III-IV (p < 0.05) cases. OS was the worst in the P + V + group. Lymphovascular and perineural invasions are independent negative prognostic factors for squamous cell carcinoma of the tongue. Patients with lymphovascular and/or perineural invasion may have significantly poorer overall survival than those without neurovascular involvement.

Rhaponticin suppresses the hypoxia-induced factor-1 alpha-mediated aggressive phenotype of tongue squamous cell carcinoma

Background

Emerging evidence suggests that rhaponticin, a stilbene monomeric compound isolated from North China rhubarb, has been shown to exhibit significant biological activity against tumors. However, the anticancer effects and mechanisms of rhaponticin in tongue squamous cell carcinoma (TSCC) remain elusive.

Objective

We investigated the changes of migration and invasion abilities and EMT progression of TSCC cells treated with different concentrations of rhaponticin under hypoxia, as well as the possible mechanisms, in order to initially explore the effects of rhaponticin on the biological characteristics of TSCC cells under hypoxia.

Results

The number of cell migration and invasion was prominently increased, E-cadherin protein was down-regulated, and N-cadherin and HIF-1α protein expression was elevated under hypoxia. Rhaponticin intervention strikingly prevented the increased abilities of migration and invasion and EMT of TSCC cells under hypoxia. This was followed by further validation finding that rhaponticin indeed leads to reduced HIF-1α post-transcriptional activity. Mechanistically, rhaponticin may bind to aryl-hydrocarbon nuclear translocator (ARNT) domain of HIF-1α.

Conclusions

Rhaponticin repressed the invasion and migration abilities and EMT process of TSCC cells under a hypoxic environment in vitro by targeted suppression of HIF-1α.

Early-onset oral cancer as a clinical entity: aetiology and pathogenesis

Oral squamous cell carcinoma (OSCC) is one of the most important medical and socio-economic problems in many of the developed countries worldwide, due to the high mortality. The incidence of OSCC among individuals under 45 years of age is growing every year; however, the aetiological factors and pathogenetic mechanisms are poorly understood. This review summarizes the available information regarding clinicopathological features, extrinsic and intrinsic aetiological factors, and the molecular and immune landscape of early-onset OSCC. This cancer shows high recurrence rates and is not associated with the aetiological factors specific to adult-onset OSCC. Young adults with OSCC are not infected with human papillomavirus and rarely consume alcohol or tobacco, but more frequently use smokeless tobacco. Data from single studies indicate the hereditary nature of early-onset OSCC: the KIR2DL1⁺-HLA-C2⁺ genotype and MMP-1 2 G allele are frequently detected in young patients. Early-onset OSCC shows specific genetic, epigenetic, transcriptomic, and proteomic changes. The tumour microenvironment in early-onset OSCC is tolerogenic rather than immunogenic. All of the data suggest that OSCC in young patients is a separate clinical entity with a specific aetiology and pathogenesis. Further studies are needed to reveal the causes and molecular targets of early-onset OSCC for the development of preventive and therapeutic strategies.