Analysis of human papilloma virus in oral squamous cell carcinoma using p16: An immunohistochemical study

Prognostic role of PD-L1 expression in head and neck squamous cell carcinoma: An institutional experience from India

BACKGROUND

Squamous cell carcinoma accounts for > 90% of Head and neck cancers and has a poor 5-year survival rate of only 50%. Immunosuppressive agents like PD-L1 inhibitors have been found to improve survival in many tumour types, including advanced/recurrent head and neck squamous cell carcinoma (HNSCC). The PD-L1 expression in this tumour can also predict clinical outcome. However, this fact still remains to be proven.

AIM

The aim was to study the expression of PD-L1 in HNSCC, correlate with clinicopathological parameters and outcome.

MATERIAL AND METHOD

This prospective study was conducted between March 2021 to June 2023 in department of Pathology of a tertiary care centre located in northern India. A total of 65 histologically confirmed cases of HNSCC were included. Expression of PD-L1 was determined by immunohistochemistry. The combined positive (CPS) and tumour proportion (TP) scores were calculated. The results were correlated with clinicopathological parameters and outcome using appropriate statistical tools.

RESULTS

Considering CPS, 42 (64.6%) cases showed expression of PD-L1. A high score of ≥ 20% was seen in 10 cases (15.4%). PD-L1 expression did not correlate with any of the clinical parameters including age, gender, addiction, site, TNM stage and HPV status. Conventional HNSCC had significantly higher expression of PD-L1. The cases with positive PD-L1 expression had a higher mean survival and a lower mortality, but the difference was not statistically significant.

CONCLUSION

PD-L1 expression is more likely to be seen in conventional HNSCC histomorphology. PD-L1 expression is a predictor of better prognosis in HNSCC.

Expression of Human Papillomavirus and the p16 Gene in Oral Potentially Malignant Disorders (OPMD): a Comparative Study With Oral Squamous Cell Carcinoma

BACKGROUND

The incidence of oral squamous cell carcinoma (OSCC) of the tongue is increasing in the younger population without traditional risk habits that lead researchers to find other related factors such as diet and viruses, especially human papillomavirus (HPV). It is noteworthy that many OSCCs develop from oral potentially malignant disorders (OPMDs). Correct diagnosis and timely management of OPMDs may help to prevent malignant transformation, and therefore it is worth seeing the involvement of HPV in OPMDs and oral cancers, as the preventive and curative measures in HPV-induced cancer types are different from the conventional types of OPMDs and OSCCs. Therefore, the main objective of this study was to identify a relationship between HPV and p16 in OPMDs and compare it with OSCC.

METHODS

This study was conducted on 83 cases of known OSCCs and OPMDs (oral submucous fibrosis, leukoplakia, and oral lichen planus). Assays, such as polymerized chain reaction (PCR) and reverse transcription-PCR, were carried out for HPV and p16 . The results were compared with clinical information and with the literature. The results were analyzed using SPSS 16.0 for windows.

RESULTS

P16 expression was mostly seen in males than in female patients. Out of 21 cases of keratosis with dysplasia, 19% expressed p16 . Of 26 oral lichen planus patients, 29% showed the p16 gene with immunohistochemistry. Interestingly, a high percentage of OSF cases expressed p16 (48.27%). Minimal expression was observed in OSCC (6.25%). HPV DNA was detected in 2.4% of the total sample. Both p16 and HPV were detected in a single case of OSCC. OPMDs expressed a significant amount of the p16 gene by immunohistochemistry and reverse transcription-PCR technique when compared with malignant lesions, suggesting a possible inactivation of the p16 gene. HPV and p16 are mostly negative in our OSCC sample, exhibiting low prevalence.

CONCLUSIONS

OPMDs expressed a significant amount of the p16 gene when compared with malignant lesions, suggesting a possible inactivation of the p16 gene. Although OSF expressed p16 , HPV was not detected, suggesting that over-expression could be independent of HPV. OSCC shows low HPV prevalence.

Human papillomavirus in oral squamous cell carcinoma using p16 and its co-relationship with cervical lymph node metastasis and clinicopathological parameters

Background

Due to the increasing prevalence of oral squamous cell carcinoma (OSCC) in Iran and especially in young people, this study aimed to identify human papillomavirus (HPV) using p16 in OSCC.

Materials and Methods

In this descriptive-analytical cross-sectional study, 40 samples from the archives of the Pathology Department of Kashani Hospital were selected by a definitive diagnosis of OSCC with neck dissection. Demographic information including age, gender, location, and size of the lesion was obtained. Samples were divided into two groups based on lymph node (LN) metastasis. Immunohistochemical staining was performed for p16. Data were entered into SPSS 24 software and statistically analyzed by t-test, ANOVA, and Spearman nonparametric test. P <0.05 was statistically significant.

Results

The mean age of patients was 59.7 ± 17.11 which in terms of age and gender there was no significant difference between the two groups including with and without cervical LN metastasis (P > 0.05). There was no significant difference between the two groups based on the grade of tumor, perninural invasion, tumor size and location (P > 0.05). The only significant difference between the two groups was based on lymphovascular invasion and disease stage (P < 0.05). The p16 expression also showed a significant difference between the two groups (P < 0.05).

Conclusion

In OSCCs without cervical LN metastasis, a significant increase in p16 expression was observed compared to samples with cervical LNs metastasis. The presence of HPV was higher in samples with less LNs metastasis and possibly a better prognosis.

Evaluation of p16 expression in oral and oropharyngeal squamous cell carcinoma

Introduction

Oral and oropharyngeal cancers together are the 6th most common cancers in the world and more than 90% are squamous cell carcinomas (OSCC, OPSCC). HPV is an important risk factor. p16 expression apart from indirectly assessing HPV infection, is an independent favorable prognostic marker. Lewis/Modified Lewis criteria of p16 grading identifies a subset of patients with improved overall survival.

Aims

(1) To evaluate p16 expression in these cancers. (2) To correlate p16 expression with age, gender, sub-site, histological type and grade. (3) To utilize the Lewis/modified Lewis criteria.

Methodology

The study included 70 cases of OSSC's and OPSCC's. Histological features were analyzed. p16 expression was determined and graded. Results were analyzed and evaluated using Chi-square test (value of P < 0.05 was taken significant).

Results

p16 positivity was seen in 46/70 (66%) cases (44 OSCC & 26 OPSCC). It was more frequent in younger patients and significantly higher in males. There was no correlation between degree of differentiation and p16 expression. In OSCC, 72.7% were p16 positive, mostly from tongue, buccal mucosa, and hard palate. p16 positivity was seen in 53.8% of OPSCCs, mostly from base of tongue and tonsil. Also, 30.4% of all cases could be included in Lewis criteria and 39.1% in modified Lewis criteria.

Conclusion

p16 is an inexpensive, easily available marker, it may be incorporated routinely in all histologically diagnosed cases of OSCC and OPSCC.

Mathematical analysis of a SIPC age-structured model of cervical cancer

Human Papillomavirus (HPV), which is the main causal factor of cervical cancer, infects normal cervical cells on the specific cell's age interval, i.e., between the G₁ to S phase of cell cycle. Hence, the spread of the viruses in cervical tissue not only depends on the time, but also the cell age. By this fact, we introduce a new model that shows the spread of HPV infections on the cervical tissue by considering the age of cells and the time. The model is a four dimensional system of the first order partial differential equations with time and age independent variables, where the cells population is divided into four sub-populations, i.e., susceptible cells, infected cells by HPV, precancerous cells, and cancer cells. There are two types of the steady state solution of the system, i.e., disease-free and cancerous steady state solutions, where the stability is determined by using Fatou's lemma and solving some integral equations. In this case, we use a non-standard method to calculate the basic reproduction number of the system. Lastly, we use numerical simulations to show the dynamics of the age-structured system.

Real-time loop-mediated isothermal amplification assay for rapid detection of human papillomavirus 16 in oral squamous cell carcinoma

OBJECTIVE

The present study established a real-time loop-mediated isothermal amplification (qLAMP) for rapid detection of human papillomavirus subtype 16 (HPV-16) in oral squamous cell carcinoma (OSCC).

METHODS

The qLAMP assay was optimized targeting the HPV-16 E7 gene. The analytical sensitivity and specificity of the assay were determined using HPV-18 (ATCC® 45152D™), HPV-35 (ATCC® 40330™), HPV-43 (ATCC® 40338™) and HPV-56 (ATCC® 40549™) viral strains and oral bacteria. HPV-16 standard curve was constructed for determination of HPV-16 viral load. The diagnostic performance of the assay was evaluated from 63 OSCC patients comprising 63 tissue, 13 saliva and 49 blood samples, in comparison with p16 immunohistochemistry (IHC), in-house PCR and nested PCR assays.

RESULTS

The detection limit of developed LAMP and PCR assays was 4.68 × 10¹ and 4.68 × 10³ copies/μl, respectively. qLAMP assay enabled detection of positive results as early as 23 min at 67 °C. This assay can detect HPV-16 positivity in 23 % (3/13) saliva and 4.8 % (3/63) tissue samples with the viral load ranging from 4.68 × 10¹ to 4.68 × 10⁴ copies/μl. HPV-16 positivity was not detected in all the blood samples. The sensitivity and specificity of qLAMP were 100 % in comparison with that of p16 IHC and nested PCR.

CONCLUSION

This study reports for the first time on the use of qLAMP assay for detection of HPV-16 in OSCC in both tissue and saliva as the sample matrix which holds promise in improving the diagnostic application owing to its rapidity, simplicity, high sensitivity and specificity.

The prevalence and clinicopathological correlation of human papillomavirus in head and neck squamous cell carcinoma in India: A systematic review article

OBJECTIVE

Head and neck squamous cell carcinoma (HNSCC) pose a great danger to society and now we have shreds of evidence for Human Papillomavirus (HPV) being one of the major causative agents for it. Though the prevalence of HPV varies throughout the world, it is gradually on the rise. The present systematic review aims to retrospect all the available studies on the prevalence of HPV in HNSCC in India and its clinicopathological aspect to study how it is different from HPV negative HNSCC.

METHODS

An objective electronic database search was conducted in PUBMED Central, MeSH, NLM Catalog, Bookshelf, and PUBMED published in 25 years period from 1994 till 2019. A total of 33 articles were shortlisted for the present review.

RESULTS

Studies conducted across India show the prevalence of HPV in Head and Neck Cancers ranging from 0-86.6%. Some studies reported that HPV positive HNSCC is more common in younger age, presents with advanced stage disease, and more commonly presents with nodal metastasis. As opposed to western literature HPV positive HNSCC in India is associated with a well-differentiated tumor grade. There is no difference in treatment outcome and survival among HPV positive and negative HNSCC.

CONCLUSION

Exact prevalence of HPV in HNSCC is still doubtful but now we have some insight into it. The prevalence of HPV in Indian HNSCC patients has risen gradually but treatment outcome and survival may be poorer compared to other countries. However definite conclusions cannot be drawn without proper prospective study.

Human Papillomavirus Detection in Oropharyngeal Squamous Cell Carcinoma Using p16 Immunohistochemistry

Introduction:

Oral cancer ranks third among all cancers in the Indian population with approximately 45% of call cancer cases in India being diagnosed as oral cancer, among which 20%–50% of the cases are observed to be associated with human papillomavirus (HPV) infection.

Aim:

This study aims to detect and evaluate the presence of p16 in oropharyngeal squamous cell carcinoma (OPSCC) patients using immunohistochemistry (IHC).

Materials and Methods:

This study was based on samples collected from 21 patients with primary OPSCC who were diagnosed and treated during the period of December 2017–March 2018. Inclusion criteria were complete clinicopathologic data, adequate clinical follow-up, and availability of sufficient paraffin-embedded tumor material. HPV immunoreactivity was further investigated by means of IHC using p16 as a marker.

Results:

IHC results revealed p16 positivity in six OPSCC cases. There was no statistically significant association of the p16 positivity of HPV with the age, gender, or site.

Conclusion:

Our results suggest that IHC-based detection of p16 provides a suboptimal prognostic information if not combined with detection of HPV DNA. Although p16 expression and HPV DNA infection are correlated with HPV-associated OPSCCs, neither of the tests alone is the optimal method for HPV status detection.

Quantitative polymerase chain reaction-based detection of HPV 16 E6 and E7 DNA in oral squamous cell carcinoma

BACKGROUND

Although human papillomavirus (HPV) is considered as a causative factor in oral squamous cell carcinoma (OSCCs), its pathogenetic role is not well established. Moreover, a limited number of studies have compared the techniques of detecting the HPV infection in OSCC. This study aimed at the detection of HPV 16 E6 and E7 DNA in OSCC by quantitative polymerase chain reaction (qPCR) technique.

METHODOLOGY

This retrospective study included 297 tissue sections obtained from histopathologically confirmed OSCC patients. The classification of tumors as poorly differentiated, moderately differentiated and well differentiated was performed by H&E staining following the WHO criteria for OSCC. The presence of HPV infection was detected by p16^INK4A expression, conventional PCR technique, HPV 16 E6, and E7 by qPCR and flow cytometry. All statistical analysis was performed using MedCalc software v.16.4.3. P < 0.05 is considered as statistically significant.

RESULTS

Of 297 samples, 128 samples were found to be HPV-positive by p16. Of total 128 HPV-positive samples, PCR, E6, and E7 qPCR were positive in 19, 97, and 98 samples, respectively. qPCR techniques were found highly significant in the detection of moderately differentiated (P < 0.0001) and widely differentiated (P < 0.0001) cases. The positivity of E6 qPCR increased as the p16 expression increased. A significant variation in E6 DNA copies was observed in different grades of p16 expression (P < 0.0001). However, overall E7 (5.4 × 10⁵ copies/μL) DNA copies were higher than E6 (7.7 × 10³ copies/μL).

CONCLUSION

qPCR detection of HPV infection is a fast, reliable, and accurate technique gives valuable information about the infection status in terms of viral load.

Roles of Human Papillomaviruses and p16 in Oral Cancer

Head and neck cancer, including oral cancer, is the sixth most common cancer in humans worldwide. More than 90% of oral cancers are of squamous cell carcinoma type. Recent studies have shown a strong relationship between human papillomavirus (HPV) infection and head and neck cancer, especially oropharyngeal squamous cell carcinoma (OPSCC) and oral squamous cell carcinoma (OSCC). Moreover, the incidence of HPV-related OSCC appears to be on the rise while HPV-unrelated OSCC tends to have stabilized in the past decades. p16, a tumor suppressor gene, normally functions as a regulator of the cell cycle. Upon infection with high-risk types of HPV (HR-HPV), particularly types 16, 18, 31, 33, 34, 35, 39, 51, 52, 56, 58, 59, 66, 68, and 70, the expression of p16 is aberrantly overexpressed. Therefore, the expression of p16 is widely used as a surrogate marker for HPV infection in head and neck cancer.