Immunohistochemical Expression Of p16INK4a Research Articles

Significance of Combined Analysis of High-Risk Human Papillomaviruses Polymerized Chain Reaction Analysis and Immunohistochemical Expression of p16INK4A in Cervical Cancer in a Cohort of South-Indian Population.

IntroductionCervical cancer is the fourth most frequent cancer in women worldwide, and it continues to be a big issue in developing countries. The current case-control study sought to determine the presence of high-risk human papillomaviruses (hr-HPV) in the development of cervical cancer, as well as their relationship with the cell cycle inhibitor gene p16INK4A in cervical cancer.MethodsThe association between p16INK4A protein and the presence of hr-HPV DNA in cervical lesions was explored in this study, which included 150 cervical cancer patients and 100 normal cervix samples. The immunohistochemistry approach was used to identify the expression of the p16INK4A protein, while the semi-quantitative polymerized chain reaction (PCR) method was used to identify the genomic identity of hr-HPV.ResultsAbout 90.67% (n=136) of the 150 case samples were found to be hr-HPV positive. Within the 136 HPV-positive samples, 45 (33.08%) show moderate expression of the p16INK4A protein, whereas 91 (66.91%) show overexpression, which is statistically significant (0.05). Among the 136 HPV-positive samples, 22.08% (N=30) were classified as having cervical intraepithelial neoplasia (CIN), with 56.66% (n=17) having CIN3, 36.66% (n=11) having CIN2, and 6.67% (n=2) having CIN1.ConclusionBased on the semi-quantitative immune staining scoring method of p16INK4A protein, genomic expression of HPV demonstrates that the expression of p16INK4A protein increases with the infectious load of the hr-HPV genome in the host cell. The result directly shows that immunostaining of the p16INK4A protein, in conjunction with the assessment of high-risk HPV in the host genome, will aid in the identification of cervical cancer in the cervix.

Molecular and Immunohistochemical Cognizance of HPV16 in Oral Leukoplakia, Oral Squamous Cell Carcinoma and Oropharyngeal Squamous Cell Carcinoma.

Prior studies have established the carcinogenic role of HPV16 and also demonstrated its unique biological behavior in cervical and oropharyngeal squamous cell carcinoma (OPSCC) but its role in oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC) is not well explored. Therefore, in the present study, we assessed HPV16 prevalence using PCR and Anti-HPV16 antibodies for the first time and correlated its biological behavior using p16INK4a and Ki67 proliferation index (PI) in OL, OSCC, and OPSCC. 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 immunohistochemistry with primary antibodies p16INK4a, Anti-HPV16, and Ki67. The expressions were evaluated and statistical analysis included Chi-square and Spearman's test. Cumulatively 37% (OL-7%, OSCC-14% & OPSCC-16%) of cases showed positive PCR expression. PCR positivity was observed to be significantly higher (p 0.00) in OPSCC (9/12) than OSCC (9/26) and OL (5/25) cases. Overall immunohistochemical expression of p16INK4a, Anti-HPV16, and Ki67 were significantly (p 0.02) higher in HPV16 (PCR) positive cases. HPV16 + OSCC cases showed higher grades of p16INK4a and Ki67 expression. We have demonstrated a prevalence of HPV16 in OL, OSCC, and OPSCC through PCR, which may be concluded as a gold standard for the detection of HPV16 DNA.

Cellular senescence evaluated by P16INK4a immunohistochemistry is a prevalent phenomenon in advanced calcific aortic valve disease

BackgroundFibrosis, calcification, and ossification are histopathologic hallmarks of calcific aortic valve disease (CAVD), a leading cause of morbidity and mortality in the aging population. Cellular senescence contributes to a functional decay in chronic diseases by intensifying tissue remodeling and impairing tissue regeneration. We evaluated the expression of P16INK4A and P53 as surrogate markers of senescence in CAVD. MethodsAortic valves from 27 individuals with severe CAVD requiring aortic valve replacement were selected for routine histologic processing. Immunohistochemical expression of P16INK4A and P53 was quantified using computerized image analysis on fields matching compartments with varying degrees of tissue remodeling. ResultsAll aortic valves demonstrated P16INK4A and P53-positive cells. The percentage of P16INK4A -positive cells, but not of P53, was higher in areas of calcification and/or ossification (57.21%±26.31, n=40) and severe fibrosis (54.79%±27.19, n=25) than in areas with minimal to mild tissue remodeling (13.69% ± 11.88, n=16, P<.0001). P16INK4A expression was observed in interstitial valve cells within all compartments proportional to the degree of fibrosis and did not correlate with age, severity of aortic stenosis, or P53 expression. Multiple linear regression analysis by backward elimination revealed P16INK4A expression was lower among statin users (P<.01). ConclusionsP16INK4A- expression is ubiquitous in calcified aortic valves and correlates with severity of tissue remodeling, suggesting a role of cellular senescence in the progression of CAVD. Further research is needed to identify possible treatment modalities as disease modifying agents for CAVD.

Immunohistochemical expression of p16INK4A in the lesions of uterine cervix

Background: Cervical cancer is the major cause of cancer deaths among women. Globally, around 5,70,000 new cases of cervical cancer and 3,11,000 deaths occurred in the year 2018. In India, Cervical cancer is a leading cause of cancer related mortality among women and the number of deaths is 60,000 per year among 97,000 diagnosed patients, especially those from lower socioeconomic group. Human Papilloma Virus (HPV) plays a crucial role in causing cervical dysplasia. This is done by upregulating p16INK4A, a cyclin dependent kinase inhibitor through interaction with cellular regulatory proteins. Hence p16INK4A can be used as a biomarker, since it is directly related variable for the presence of HPV. This study was conducted to evaluate the expression of p16INK4A in benign, premalignant and malignant cervical lesions and to assess its utility in diagnosing and grading cervical lesions.&#x0D; Methods: A total of 80 cervical specimens categorized histopathologically into nonspecific cervicitis, low grade squamous intraepithelial neoplasia (LSIL), high grade squamous intraepithelial neoplasia (HSIL) and squamous cell carcinoma cervix were included in this prospective study of one-year duration. Immunohistochemical study of p16INK4A were interpreted qualitatively and semi-quantitatively by Allred scoring system (0 to 8 points) which measures the proportion of stained cells and intensity of staining of cells. The collected data were statistically analyzed by ANOVA and chi square test.&#x0D; Result: Qualitative method showed absence of p16INK4A expression in all nonspecific cervicitis. 16.7% (2/12) LSIL, 100% (12/12) HSIL and 100% (28/28) squamous cell carcinoma cases showed p16INK4A positivity. Allred scoring of p16INK4A showed 66% (8/12) HSIL and 85.7% (24/28) squamous cell carcinoma cases with score 3 positivity. Hence high-grade lesions showed higher expression of this marker.&#x0D; Conclusion: IHC expression of p16INK4A showed increasing degree of expression from benign to premalignant and malignant lesions suggesting its diagnostic and prognostic value in the cervical cancer management

Expression of P16INK4a in Uveal Melanoma: New Perspectives.

Uveal melanoma (UM) is the most common intraocular tumor in adults. Despite sharing the name and similar morphological features with cutaneous melanoma (CM), it is an entirely different neoplasia with a particular genetic background and clinical behavior. CDKN2A is a gene located at chromosome 9p21, encoding for P16INK4a and P14(ARF) proteins, whose role as a tumor suppressor has been clearly defined in many malignant tumors. CDKN2A frequently presents germline mutations in familial CM and epigenetic downregulation in a considerable percentage of sporadic CM. It has been hypothesized that CDKN2A alterations are early events in CM development, playing a central role in the malignant transformation of melanocytes. Alterations of the CDKN2A gene reduce the expression of P16INK4a in most CM subtypes. Immunohistochemical evaluation of P16INK4a is currently used, in association with Ki67 and HMB45, in pathology practice to discriminate between dysplastic nevi and melanoma. On the other hand, CKDN2A is rarely mutated in UM, and the immunohistochemical expression of P16INK4a has only been reported in small case series. We tested P16INK4a expression on paraffin-embedded tissue sections from 9 tissue microarrays (TMAs), built with 2 mm cores derived from 133 uveal melanoma FFPE blocks, collected from 1990 to 2018, and from selected paraffin-blocks of 3 UM liver metastases. The immunohistochemical expression of P16INK4a was assessed with a visual evaluation by light microscopy and then with a digital approach. Both approaches, with an acceptable concordance rate, revealed P16INK4a expression in a large proportion of UM cases and all liver metastases, opening new possibilities of using it in the differential diagnosis between cutaneous and uveal melanoma metastases in cases of unknown primary tumor or patients with two different primary melanomas.

Immunohistochemical Expression of P16ink4a in Colorectal Adenocarcinoma Compared to Adenomatous and Normal Tissue Samples: A Study on Southeast Iranian Samples

Background: Colorectal cancer (CRC) is one of the most common neoplasms of the digestive system with high morbidity and mortality. Treatment of CRC in advanced metastatic stages is problematic. Thus, early diagnosis in primary stages using sensitive molecular markers seems to be necessary. Objectives: This study aimed at investigating the immunohistochemical expression of P16ink4a in CRC compared to adenomatous and normal colorectal tissue samples of a population from the southeast of Iran. Methods: This case-control study was conducted on 137 colorectal formalin fixed paraffin-embedded tissue blocks for P16ink4a a protein using Immunohistochemistry (IHC). The tissue blocks were categorized in 3 groups, including adenocarcinoma (n = 63), adenomatous (n = 38), and normal (n = 36). All tissue blocks were collected from the pathology department of Ali-Ebne-Abitaleb central and referral Hospital, Zahedan, Iran from 2010 to 2015. The sections were evaluated using semi-quantitative scoring. The P16ink4a expression was reported as negative and positive. Clinicopathological characteristics were also assessed. The data were analyzed by Kruskal-Wallis and Fisher exact tests. The significance level was considered as P < 0.05. Results: The expression of P16ink4a in adenocarcinoma, adenomatous, and normal colorectal tissues was 25.40%, 50.00%, and 69.50%, respectively. The P16ink4a expression was significantly higher in non-neoplastic tissues compared to the adenomatous and colorectal tissues (P < 0.001). There was a significant association between P16ink4a expression and differentiation grade (P < 0.001) and primary location of the tumor (P = 0.010). Conclusions: Considering the significant expression of P16ink4a in normal compared to adenomatous and cancerous samples, it seems that this biomarker could be used as a potential useful predictor for screening and diagnosis of CRC patients in early stages. Further researches should be conducted on this matter.

HPV-associated p16 INK4A expression and response to therapy and survival in selected head and neck cancers.

Development of squamous cell cancer of head and neck (SCCHN) is associated with human papillomavirus (HPV) infection, which in turn is closely related with expression of p16 INK4A. Loss of p16 INK4A expression by deletion, mutation, or hypermethylation is common in SCCHN. We here evaluated p16 INK4A as a prognostic marker of treatment response and survival in our SCCHN patients with laryngeal, hypopharyngeal or nasopharyngeal cancers. 131 patients diagnosed with SCCHN between January 2,2006 and July 17, 2010 were examined for p16 INK4A. The median age was 60 years (15-82 years). Fifty one patients were stage I-II and 80 were stage III-IV. Immunohistochemical expression of p16 INK4A was analyzed in pretreatment paraffin-embedded tumor blocks. The influence of p16 INK4A status on disease-free survival, and overall survival after treatment was evaluated. P16 INK4A positivity was found in 58 patients (44%). Tumor-positivity for p16INK4A was correlated with improved disease free survival (70.1 months vs 59 months) and improved overall survival (2, 3 and 5-year values; 77% vs 72%, 70% vs 63% and, 63% vs 55%; respectively). On multivariate analysis, stage was determined as independent prognostic factor for disease-free survival. Stage was the major prognostic factor on treatment response and survival in our patients. P16 INK4A status predicts better outcome in laryngeal, hypopharyngeal or nasopharyngeal cancer cases treated with surgery plus adjuvant radiochemotherapy as well as with definitive radiation therapy and/or chemotherapy.

Concurrent radiotherapy plus epidermal growth factor receptor inhibitors in patients with human papillomavirus-related head and neck cancer

Concurrent radio-chemotherapy (RT-CT) is the standard treatment for locally advanced head and neck squamous cell carcinoma (LA-HNSCC), but RT plus epidermal growth factor receptor (EGFR) inhibitors is an effective option when CT is not appropriate. Human papillomavirus (HPV) is associated with an improved prognosis in LA-HNSCC; however, it has not been fully studied as a prognostic factor after RT + EGFR inhibitors. Immunohistochemical expression of p16INK4A and PCR of HPV16 DNA were retrospectively analyzed in tumor blocks from 52 stage III/IV LA-HNSCC patients treated with RT + EGFR inhibitors. Disease-free survival (DFS) and overall survival (OS) were analyzed by the Kaplan-Meier method. DNA of HPV16 was found in six of 52 tumors (12 %) and p16 positivity in eight tumors (15 %). After a median follow-up time of 45 months (6-110), p16-positive patients treated with RT + EGFR inhibitors showed an improved DFS (2-year DFS 75 vs. 44 %, HR 0.25, 95 % CI 0.06-0.99, p = 0.047) compared with p16-negative patients. These differences were outperformed when compared by HPV16 status (2-year OS rates of 83 vs. 58 %, HR 0.17, 95 % CI 0.02-0.99, p = 0.049 and 2-year DFS rates of 83 vs. 45 %, HR 0.17, 95 % CI 0.02-0.99, p = 0.049). In the Cox regression analysis with OS as the end point, ECOG 0-1 was the only prognostic factor independently associated with a good prognosis in the multivariable analysis. In this study, p16/HPV16-positive patients with LA-HNSCC treated with RT + EGFR inhibitors showed a better survival, not confirmed in multivariate analysis.

Chlamydia trachomatis and human papillomavirus coinfection: association with p16INK4a and Ki67 expression in biopsies of patients with pre-neoplastic and neoplastic lesions

The objective of this study was to identify the frequency of coinfection by human papillomavirus (HPV) and Chlamydia trachomatis (CT) in cervical lesions and relate it with immunohistochemical expression of p16INK4a and Ki67, both oncogenicity markers. A cross-sectional study with 86 women from primary care units in southern Brazil was conducted. Cervical swabs were collected for HPV-DNA and CT-DNA detection, through the polymerase chain reaction technique (PCR). The immunohistochemical analysis was performed on biopsy cervical tissue material to identify the expression of p16INK4a and Ki67 cell cycle markers. About 83 % were positive for HPV-DNA and 19% had coinfection with CT-DNA. Among coinfected women, 56% expressed p16INK4a. There was a statistically significant association between the histological grade of the lesion and Ki67 expression. All high-grade lesions, 50% of low-grade lesions and 31% of negative biopsies expressed Ki67 (p = 0.004). A total of 37% of coinfected women expressed both markers. In conclusion, although more than half of the coinfected patients have expressed p16INK4a and more than one third have expressed both markers, these results suggest no association between those variables. However, other studies involving larger samples are necessary to corroborate such findings.

Chlamydia trachomatis and human papillomavirus coinfection: association with p16INK4a and Ki67 expression in biopsies of patients with pre-neoplastic and neoplastic lesions

The objective of this study was to identify the frequency of coinfection by human papillomavirus (HPV) and Chlamydia trachomatis (CT) in cervical lesions and relate it with immunohistochemical expression of p16INK4a and Ki67, both oncogenicity markers. A cross-sectional study with 86 women from primary care units in southern Brazil was conducted. Cervical swabs were collected for HPV-DNA and CT-DNA detection, through the polymerase chain reaction technique (PCR). The immunohistochemical analysis was performed on biopsy cervical tissue material to identify the expression of p16INK4a and Ki67 cell cycle markers. About 83 % were positive for HPV-DNA and 19% had coinfection with CT-DNA. Among coinfected women, 56% expressed p16INK4a. There was a statistically significant association between the histological grade of the lesion and Ki67 expression. All high-grade lesions, 50% of low-grade lesions and 31% of negative biopsies expressed Ki67 (p=0.004). A total of 37% of coinfected women expressed both markers. In conclusion, although more than half of the coinfected patients have expressed p16INK4a and more than one third have expressed both markers, these results suggest no association between those variables. However, other studies involving larger samples are necessary to corroborate such findings.

Maximum Standardized Uptake Value of F-18 FDG-PET Inversely Correlated with Immunoexpression of p16INK4a in Patients with Non-Small Cell Lung Cancer

We have studied the possible relationship between the immunohistochemical expression of p16 INK4a and the maximum standardized uptake value (SUV max) of F-18 fluorodeoxyglucose-positron emission tomography (F-18 FDG- PET) in 49 patients with non-small cell lung cancer (NSCLC). Immunohistochemical negativity of p16 INK4a was verified in 71.4 % of the patients, higher in squamous cell carcinomas than in adenocarcinomas (p: 0.033). The SUV max corre- lates with negativity for p16 INK4a (p: 0.042) and was higher (p: 0.024) in cases with p16 INK4a -negative (17.3 ± 8.3) than in cases with p16 INK4a -positive (12.7 ± 5.2). We can conclude that inactivation of the p16 INK4a gene is very frequent in NSCLC, with higher values in squamous cell carcinomas. SUV max correlated positively and statistically with negativity for p16 INK4a , which could explain why higher estimates of SUV max are found in squamous cell carcinomas when com- pared to adenocarcinomas. Only the clinical stage was found to be an independent prognostic value after multivariate analysis.

Immunohistochemical Expression of p16INK4A, Ki-67, and Mcm2 Proteins in Gastrointestinal Stromal Tumors: Prognostic Implications and Correlations with Risk Stratification of NIH Consensus Criteria

Inactivation of p16(INK4A) promotes G1/S progression of cell cycle. Minichromosome maintenance protein-2 (Mcm2), a novel cell proliferation marker, is known to better correlate with clinical outcomes than Ki-67 in many carcinomas. Since gastrointestinal stromal tumors (GISTs) sometimes remains challenging in prognostication, we analyzed the utility of these three markers in GISTs. Immunohistochemistry was performed in tissue microarrays of 277 primary GISTs and correlated with NIH consensus criteria and clinical outcomes. The increment of NIH risk levels significantly correlated with increasing labeling indices (LI) of both Ki-67 (P <.001) and Mcm2 (P <.001) and loss of p16(INK4A) expression (P <.035). However, the latter aberration did occur in 23% of very low/low-risk GISTs. The relationship between Mcm2 and Ki-67 LIs could be modeled as linear (P <.001, r = 0.697), while Mcm2 LI was considerably higher (P <.001) with a stepwise escalation related to risk levels. Ki-67 LI >5% (P <.0001) and Mcm2 LI >10% (P <.0001) were strongly predictive of inferior disease-specific survival (DSS), while aberrant loss of p16(INK4A) only reached a trend (P = .0954). In multivariate analyses, independent adverse factors of DSS were high-risk category (RR = 16.93, P <.0001), metastatic disease (RR = 4.12, P = .0015), Ki-67 LI >5% (RR = 3.55, P = .001), and presence of epithelioid histology (RR = 2.17, P = .0308). Prognostic efficacy of NIH consensus criteria is substantiated. P16(INK4A) deregulation can occur early in GIST tumorigenesis and marginally correlates with patient survival. Despite Ki-67 LI being an independent prognosticator, simultaneous detection of Mcm2 is recommended as a prognostic adjunct of GISTs, given its better sensitivity and stepwise escalation with increasing risk levels.

P16INK4a Overexpression Independent of Human Papillomavirus Infection in Lobular Endocervical Glandular Hyperplasia

A high rate of human papillomavirus (HPV) infection has been reported in cervical cancer and precancerous lesions. Many studies also have shown that p16INK4a overexpression is of diagnostic value for high-risk HPV-related cervical cancer and precursors. Lobular endocervical glandular hyperplasia (LEGH) is a rare lesion of the uterine cervix. There is one report about HPV infection and few studies on p16INK4a expression in LEGH. Therefore, we 1) detected HPV infection and examined p16INK4a expression and 2) observed the relationship between HPV and p16INK4a overexpression in LEGH. The immunohistochemical expression of p16INK4a was studied in 24 cases of LEGH. HPV DNA was also evaluated in these cases using a polymerase chain reaction technique. Strong (++) p16INK4a immunoreactivity was observed in 10 (41.7%) of the 24 LEGH cases; a moderate (+) pattern was observed in 9 (37.5%) cases; a weak (+) pattern was observed in 2 (8.3%) cases; and the remaining 3 (12.5%) cases showed negative expression. Overall, p16INK4a overexpression was seen in 87.5% of the cases (21/24). HPV DNA was not detected in any of the 24 LEGH cases. These results suggest that p16INK4a overexpression is independent of HPV infection in LEGH.

Immunohistochemical expression of p16INK4a is predictive of HR-HPV infection in cervical low-grade lesions

The p16INK4a is a cyclin-dependent kinase inhibitor that decelerates the cell cycle by inactivating the cyclin-dependent kinases involved in the phosphorylation of the retinoblastoma protein (RB). Expression of E6 and E7 oncogenes of high-risk (HR) human papillomavirus (HPV), affecting the RB-p16 pathway, leads to p16 upregulation. Although it is widely reported that p16 is overexpressed in a high percentage of preneoplastic lesions and in almost all carcinomas of the uterine cervix, protein upregulation and its correlation with HPV infection in low-grade lesions is still being debated. In this study, we investigated in parallel, p16 expression and HPV infection in 100 cervical biopsies (17 normal tissues, 54 CIN1, 10 CIN2, 11 CIN3, eight invasive squamous cancers). Results obtained demonstrated that none of the 17 normal cervical tissues, evaluated by immunohistochemistry, presented p16 positivity whereas, starting from CIN1 (31%) to CIN2 (90%), CIN3 (100%) and carcinomas (100%), a constant and significant increase of protein overexpression (P<0.0001) was observed. In addition, p16 overexpression consistently showed elevated sensitivity (84%) and specificity (98%) in detecting HR-HPV infection with a high positive predictive value (97%) and negative predictive value (86%). Of interest, 93% of the p16-positive CIN1 were also HR-HPV infected. Our findings confirmed that p16 overexpression is associated to high-grade precancerous lesions and cervical carcinomas, and further demonstrated that immunohistochemical evaluation of p16 may be a useful biomarker in identifying HR-HPV-infected low-grade lesions.