HPV involvement in OSCC: Correlation of PCR results with light microscopic features

lncRNA TMEM161B-AS1 screened the onset of oral squamous cell carcinoma in HPV-infected patients, predicted poor prognosis, and regulated cell progression via modulating the miR-651-5p/BDNF axis

Oral squamous cell carcinoma (OSCC) has become the most common HPV-related cancer with high invasion and metastasis. Exploring biomarkers for the screening and monitoring of OSCC, especially for the HPV-OSCC, would benefit patients' diagnosis and prognosis. This study evaluated the significance and mechanism of TMEM161B-AS1 and miR-651-5p in HPV-OSCC aiming to provide novel insight into the mechanism of HPV-OSCC development. Expression of TMEM161B-AS1 and miR-561-5p was analyzed in healthy individuals, HPV-infected non-OSCC patients, and HPV-OSCC patients using PCR. Their significance in HPV-OSCC occurrence and prognosis was evaluated by logistic regression, ROC, Kaplan-Meier, and Cox regression analysis. In OSCC cells, CCK8 and Transwell assays were employed for assessing cell growth and metastasis. The luciferase reporter assay and cell transfection were performed to evaluate the regulatory association between TMEM161B-AS1, miR-561-5p, and BDNF. Significant upregulation of TMEM161B-AS1 and downregulation of miR-561-5p were observed in oral HPV-infected patients. Both TMEM161B-AS1 and miR-651-5p served as risk factors for the occurrence of OSCC in oral HPV-infected patients and could distinguish HPV-OSCC patients from HPV-infected non-OSCC patients. Increased TMEM161B-AS1 and reduced miR-561-5p indicated severe development and adverse prognosis of HPV-OSCC patients. In OSCC cells, silencing TMEM161-AS1 suppressed cell proliferation and motility via negatively modulating miR-561-5p. miR-561-5p negatively regulated BDNF, which was considered the underlying mechanism of TMEM161B-AS1. Increasing TMEM161B-AS expression and decreasing miR-561-5p showed the occurrence of OSCC in HPV-infected patients and predicted malignant development and adverse prognosis. TMEME161B-AS1 served as a tumor promoter via regulating the miR-561-5p/BDNF axis.

Application of the Bethesda system of reporting for cervical cytology to evaluate human papilloma virus induced changes in oral leukoplakia, oral squamous cell carcinoma, and oropharyngeal squamous cell carcinoma: A cytomorphological and genetic study

BACKGROUND

Human papilloma virus (HPV) has a well-established carcinogenic role in certain head and neck cancers. These HPV associated cancers possess unique clinicopathological behavior and exhibits better prognosis than their negative counterparts. Detection through polymerase chain reaction (PCR) has been considered as the "gold standard" but imposes burden in low resource settings. Therefore, in the present study, we assessed the validity of cytomorphological features for the detection of HPV in oral leukoplakia (OL), oral squamous cell carcinoma (OSCC), and oropharyngeal squamous cell carcinoma (OPSCC).

METHODOLOGY

This study included 63 subjects comprising of 25 OL, 26 OSCC, and 12 OPSCC cases. Exfoliated cells were collected and processed for PCR followed by Papanicolaou staining and subsequent grading. Additionally the non-classical signs were evaluated and statistical analysis included Chi-square and Spearman's test.

RESULT

23/63 (36.5%) cases showed PCR positivity for HPV16. Most of the cytomorphological features showed significant correlation for the presence of HPV. A greater sensitivity and specificity was observed in the Bethesda system for reporting cervical cytology (TBS) than the Papanicolaou grading system.

CONCLUSION

We conclude that the non-classic cytological features could be employed in the detection of HPV in low resource settings with improved sensitivity. Liquid based cytology graded using TBS could be suitable for oral cytology in the detection of early atypical changes.

Silencing of LINC01116 suppresses the development of oral squamous cell carcinoma by up-regulating microRNA-136 to inhibit FN1

Background

Oral squamous cell carcinoma (OSCC), one of the most common cancers worldwide with a high mortality rate, is accompanied by poor prognosis, highlighting the significance of early diagnosis and effective treatment. Long non-coding RNAs (lncRNAs) have been linked with the development and progression of various cancers. In this study, aberrantly expressed lncRNA LINC01116, microRNA-136 (miR-136), and fibronectin1 (FN1) were identified in OSCC using a microarray analysis. Therefore, this study aimed to investigate the role of LINC01116/miR-136/FN1 regulatory axis in OSCC.

Methods

The gain-of-function and loss-of-function experiments in vitro were performed to alter the expression of LINC01116 and miR-136 in OSCC cells to elucidate their effects on cellular processes, including epithelial-mesenchymal transition (EMT), viability, invasion, and migration. In addition, the interaction among LINC01116, miR-136, and FN1 was identified. Additionally, the tumorigenicity and lymph node metastasis (LNM) affected by LINC01116 were observed through xenograft tumor in nude mice.

Results

LINC01116 and FN1 were abundant in both OSCC tissues and cells, while miR-136 was poorly expressed. LINC01116 could competitively bind to miR-136, which targets and negatively regulates FN1. Moreover, in response to LINC01116 silencing or miR-136 over-expression, OSCC cells exhibited diminished EMT process and inhibited cell viability, invasion, and migration in vitro, coupling with impaired tumorigenicity and LNM in vivo.

Conclusion

The fundamental findings in this study collectively demonstrate that LINC01116 silencing may inhibit the progression of OSCC via the miR-136-mediated FN1 inhibition, highlighting a promising therapeutic strategy for OSCC treatment.

Benign proliferative epithelial lesions of oral mucosa are infrequently associated with α-, β-, or γ human papillomaviruses

BACKGROUND

Oral papillomas and verruca vulgaris have been associated with human papillomavirus (HPV) infection. However, approximately half of these have remained HPV-negative when tested for mucosal HPV genotypes. In this study, we evaluated presence of α-, β-, and γ-HPVs in benign papillary and verrucous lesions.

METHODS

Eighty-three clinical lesions with suspected HPV etiology were analyzed for HPV types of genus α (n = 24), β (n = 46), and γ (n = 52). Immunohistochemistry was used for p16 as a possible surrogate marker of high-risk HPV, accompanied by Ki-67 proliferation marker.

RESULTS

Altogether, α-HPVs were detected in 6.4%, β-HPVs in 2.4%, and γ-HPV in 4.8%. The following genotypes were identified: HPV6, 8, 11, 16, 22, 161, and 170. Neither Ki-67 nor p16 positivity alone were associated with HPV but combined staining showed significant inverse association (P = .042).

CONCLUSION

HPV infection is found only in a minority of benign verrucous and papillary oral lesions, with the predominance of α-HPVs.

LEVEL OF EVIDENCE

4.

A Comparative Immunohistochemical Study of Presence and Distribution Pattern of Stromal Myofibroblast in Oral Dysplasia and in Different Grades of Oral Squamous Cell Carcinoma

Aims and Objectives:

Squamous cell carcinoma (SCC) is a common oral malignancy with a poor survival rate. Early tumorigenesis is marked by transdifferentiation of fibroblasts to myofibroblasts (MFs), which is supported by growth factors and cytokines expressed by tumor cells. The expression of alpha-smooth muscle actin (αSMA) marker correlates with the activation of MFs. This study was undertaken to compare the frequency and distribution of αSMA immunoexpression in oral epithelial dysplasia (OED) and OSCC.

Materials and Methods:

This study was conducted on samples collected from patients with oral epithelial dysplasia and oral SCC who visited Rajarajeswari Dental College and Hospital, Bengaluru. Tissue sections were subjected to Immunohistochemistry using αSMA marker, and cells were counted. The obtained data was subjected to Kruskal–Wallis test and Mann–Whitney U-test.

Results:

On performing Kruskal–Wallis test and Mann–Whitney U-test between the three groups (normal oral mucosa, OED, and OSCC) statistically significant result was found in the frequency between OED and OSCC and between normal tissue and OSCC. On comparing the distribution pattern, statistically significant result was found between OED and OSCC and between normal tissue and OSCC.

Conclusion:

The expression of MFs increases as the disease progresses from high-grade epithelial dysplasia to invasive OSCC. Poorly differentiated SCC showed more attendance of positive MFs in the stroma than other grades of OSCC. The rise in the number of αSMA-positive MFs and change in distribution pattern in OSCC can be associated with tumor invasive characteristics. Thus, the proliferation of MFs may be used as a stromal marker of premalignancy and malignancy.

Detection of human papilloma virus-E6/E7 proteins of high-risk human papilloma virus in saliva and lesional tissue of oral squamous cell carcinoma patients using nested multiplex polymerase chain reaction: A comparative study

INTRODUCTION

Human papilloma virus (HPV)-associated oral squamous cell carcinoma (OSCC) shows different biological behavior as compared to tobacco-induced OSCC. Mere presence of HPV in OSCC is of no clinical significance; however, the integration of HPV-DNA through E6/E7 gene into the host genome is important as it affects the development and progression of OSCC.

AIM

The aim of this study was to determine the presence of E6/E7 proteins of high-risk (HR) HPV (HPV16 and HPV18) in saliva as well as lesional tissue of OSCC patients and to determine the use of saliva as an alternative to tissue for E6 and E7 proteins in OSCC.

MATERIALS AND METHODS

Histopathologically confirmed 47 cases of OSCC were taken up for the study. The tumor tissue and saliva sample of each patient were obtained to detect the presence of HPV16 and HPV18 along with E6/E7 proteins in both samples by nested multiplex polymerase chain reaction (NMPCR). The data were analyzed using Student t-test (2 tailed) and Wilcoxon signed-ranks test.

RESULTS

In tumor tissue, 40.42% of cases showed HPV16 (19/47) positivity while 34.04% were HPV18 (16/47) positive; whereas, in salivary sample, 31.91% showed HPV16 (15/47) positivity while 25.53% of cases were HPV18 positive (12/47). Mean age of participants was 46.7 years, males showed no significant difference from females in the prevalence of HPV 16/18 with tongue being the most common site for the occurrence. There was no statistically significant difference for HPV16/18 presence in tissue and saliva sample of OSCC. Taking lesional tissue sample as standard, sensitivity and specificity for HPV16 and HPV18 in saliva by NMPCR was estimated at 68.42% and 92.86%, respectively. The accuracy level of NMPCR detection for HPV16 was 82.98% and HPV18 was 65.96%.

CONCLUSION

The study revealed no significant difference in the prevalence of HPV (16/18) among tissue and saliva of OSCC patients in Indian population. The study also found no difference in the level of DNA content of HPV in saliva and tissue indicating that saliva can be used as an alternative predictor of HPV positivity in OSCC.

Prevalence of human papillomavirus16 DNA and p16INK4a protein in oral squamous cell carcinoma: A systematic review and meta-analysis

BACKGROUND AND AIM

Indian patients with oral squamous cell carcinoma (OSCC) are etiologically associated with the use of tobacco and alcohol; yet, a proportion of tumors that may harbor human papillomavirus (HPV) infections cannot be neglected. The following meta-analysis was conducted to address the association of p16INK4a and HPV DNA with OSCC. In addition, the study also provides the updated prevalence of HPV-induced OSCC.

MATERIALS AND METHODS

Literature survey was performed using databases such as PubMed with the help of the following keywords - "HPV infection," "oral squamous cell carcinoma," "p16INK4a," "HPV DNA," "E6," "E7," "L1," "L2" and "LCR." Proportion method was performed to derive the forest plot using MedCalc statistical software version 16.4.3.

RESULTS

Among 145 research articles, 33 articles were selected for further analysis, in which 13 articles were related to HPV DNA detection in tissues, 11 articles detected the overexpression of p16INK4a and nine articles reported the detection of both HPV DNA and p16INK4a expression. Meta-analysis revealed significant heterogeneity (P < 0.0001) among the articles. Overall, the study consisted of 3339 patients with OSCC, among which 559 patients were diagnosed with the presence of HPV16 DNA with a random proportion of 20.1% at 95% confidence interval (CI) (13.9-27.1, P < 0.0001). Overexpression of p16INK4a protein was observed in 709 patients with a random proportion of 25.4% at 95% CI (14.3-38.3, P < 0.0001).

CONCLUSION

HPV DNA and expression of p16INK4a was suggested as gold standard for the detection of HPV infection in many cases of cancers. Frequency of HPV infection is significantly higher in patients with OSCC as identified through the detection of HPV DNA and p16INK4a expression. Even though the association of HPV infection has been established in head and neck cancer, this review could further the establishment of molecular level interaction of HPV in patients with oral cancer.