Expression of ezrin in oral squamous cell carcinoma: Prognostic impact and clinicopathological correlations

Moesin Serves as Scaffold Protein for PD-L1 in Human Uterine Cervical Squamous Carcinoma Cells

Immune checkpoint blockade (ICB) therapy targeting the programmed death ligand-1 (PD-L1)/PD-1 axis has emerged as a promising treatment for uterine cervical cancer; however, only a small subset of patients with uterine cervical squamous cell carcinoma (SCC) derives clinical benefit from ICB therapies. Thus, there is an urgent unmet medical need for novel therapeutic strategies to block the PD-L1/PD-1 axis in patients with uterine cervical SCC. Here, we investigated the involvement of ezrin/radixin/moesin (ERM) family scaffold proteins, which crosslink several plasma membrane proteins with the actin cytoskeleton, on the plasma membrane localization of PD-L1 in BOKU and HCS-2 cells derived from human uterine cervical SCC. Immunofluorescence analysis showed that PD-L1 colocalized with all three ERM proteins in the plasma membrane. Gene knockdown of moesin, but not ezrin and radixin, substantially reduced the plasma membrane expression of PD-L1, with limited effect on mRNA expression. An immunoprecipitation assay demonstrated the molecular interaction between PD-L1 and moesin. Moreover, phosphorylated, i.e., activated, moesin was highly colocalized with PD-L1 in the plasma membrane. In conclusion, moesin may be a scaffold protein responsible for the plasma membrane expression of PD-L1 in human uterine cervical SCC.

Platelet CLEC2-Podoplanin Axis as a Promising Target for Oral Cancer Treatment

Cancer tissues are not just simple masses of malignant cells, but rather complex and heterogeneous collections of cellular and even non-cellular components, such as endothelial cells, stromal cells, immune cells, and collagens, referred to as tumor microenvironment (TME). These multiple players in the TME develop dynamic interactions with each other, which determines the characteristics of the tumor. Platelets are the smallest cells in the bloodstream and primarily regulate blood coagulation and hemostasis. Notably, cancer patients often show thrombocytosis, a status of an increased platelet number in the bloodstream, as well as the platelet infiltration into the tumor stroma, which contributes to cancer promotion and progression. Thus, platelets function as one of the important stromal components in the TME, emerging as a promising chemotherapeutic target. However, the use of traditional antiplatelet agents, such as aspirin, has limitations mainly due to increased bleeding complications. This requires to implement new strategies to target platelets for anti-cancer effects. In oral squamous cell carcinoma (OSCC) patients, both high platelet counts and low tumor-stromal ratio (high stroma) are strongly correlated with increased metastasis and poor prognosis. OSCC tends to invade adjacent tissues and bones and spread to the lymph nodes for distant metastasis, which is a huge hurdle for OSCC treatment in spite of relatively easy access for visual examination of precancerous lesions in the oral cavity. Therefore, locoregional control of the primary tumor is crucial for OSCC treatment. Similar to thrombocytosis, higher expression of podoplanin (PDPN) has been suggested as a predictive marker for higher frequency of lymph node metastasis of OSCC. Cumulative evidence supports that platelets can directly interact with PDPN-expressing cancer cells via C-type lectin-like receptor 2 (CLEC2), contributing to cancer cell invasion and metastasis. Thus, the platelet CLEC2-PDPN axis could be a pinpoint target to inhibit interaction between platelets and OSCC, avoiding undesirable side effects. Here, we will review the role of platelets in cancer, particularly focusing on CLEC2-PDPN interaction, and will assess their potentials as therapeutic targets for OSCC treatment.

Risk factors associated with the mortality rate of oral squamous cell carcinoma patients: A 10-year retrospective study

In Malaysia, oral cancer is very common and the reported 5-year survival of such patients is nearly 50% after treatment with surgery and radiotherapy, much lower than most of the developed countries. This study aimed to investigate the socio-demographic and clinicopathological parameters that influence the mortality rate of the patients suffering from oral squamous cell carcinoma (OSCC) in the Kelantanse population.In this retrospective study, data regarding socio-demographic, clinicopathological factors, and treatment outcome associated with OSCC were gathered from the archives of the medical records office of Hospital Universiti Sains Malaysia. For statistical analysis, simple and multiple logistic regression were performed. The significance level was set to P < .25.A total of 211 OSCC cases were registered in Hospital Universiti Sains Malaysia from January 1, 2000 to December 31, 2018. Majority of them were male (57.82%), non-smoker (54.97%), non-alcohol consumer (91.94%), and non-betel quid chewer (93.83%) Malay (60.66%) patients. The tongue was the most commonly involved part of the oral cavity (41.52%). Histologically, the majority of the cases had moderately-differentiated OSCC (52.82%). Most of the patients were diagnosed at stage IV at the time of diagnosis (61.61%). When this study was performed, the survival status of the majority of the patients was alive (68.24%).Within the analyzed socio-demographic and clinicopathological parameters, gender, alcohol consumption, T-classification, histological grading, and treatment status have been demonstrated as an independent risk factors for mortality rate in multivariate analysis. Hence, these parameters need to be taken into account for the individualized therapy management of OSCC patients.

Podoplanin expression in oral leukoplakia─a prospective study

PURPOSE

The aim of this prospective work was to examine oral leukoplakia for their podoplanin expression to determine whether podoplanin expression is associated with the degree of dysplasia.

MATERIALS AND METHODS

We took biopsy samples from 50 patients with oral leukoplakia in 2013. The preparations studied by immunohistochemistry were analyzed in correlation with the degree of dysplasia and other clinicopathological variables.

RESULTS

The Chi-square test showed a significant correlation between podoplanin expression and the degree of dysplasia according to the squamous intraepithelial neoplasia (SIN) classification (p = 0.033). Also, a significant association between age grouping and podoplanin expression was found. We were able to show that the distribution is the same for both age groups in relation to the score of podoplanin expression (p = 0.003).

CONCLUSION

In a comparable retrospective work of our working group, it could be shown that podoplanin is a reliable predictive marker for the assessment of the risk of malignant transformation. The present work was able to substantiate the assumption that podoplanin not only plays an important role in the context of malignant degeneration but also exerts a major influence in advance.