Efficiency of immunohistochemical p16 expression and HPV typing in cervical squamous intraepithelial lesion grading and review of the p16 literature

Assessment and clinicopathological correlation of p16 expression in cervical squamous cell carcinoma of Indian population: Diagnostic implications

BACKGROUND

Our aim was to assess the p16 expression in normal cervical epithelium and cervical lesions and how it correlated with HPV oncoprotein E7 and other etiological parameters of cervical cancer.

METHODS

For this purpose, we analyzed protein expression of p16 and E7 oncoprotein in total 20 normal cervical epithelium tissue (as control) and 62 cervical lesions. Next, the result was correlated with different clinico-pathological parameters.

RESULTS

Out of 62 cases of cervical lesions, we found around 75%-100% of the cervical lesion samples exhibited E7 nuclear protein expression, whereas around 33.33%-75% samples were p16 positive. On the other hand, p16 expression showed strong association with E7 oncoprotein and other clinico-pathological parameters (like high parity, early age of sextual debut) in the same set of samples of our study.

CONCLUSION

We concluded that overexpression of p16 is very practical and can be readily implemented in most diagnostic pathology laboratories.

Observation of the cervical microbiome in the progression of cervical intraepithelial neoplasia

OBJECTIVE

Cervical microbial community in the cervical intraepithelial neoplasia and cervical cancer patients was analysed to study its composition, diversity and signalling pathways by high-throughput 16S rDNA sequencing,and the candidate genes associated with occurrence and progression of cervical intraepithelial neoplasia were screened out and the model was established to predict the evolution of cervical intraepithelial neoplasia malignant transformation from the cervical microbial genes aspect.

METHODS

Cervical tissues of normal, cervical intraepithelial neoplasia and cervical cancer patients without receiving any treatment were collected. The correlation between candidate genes and cervical intraepithelial neoplasia progression was initially determined by analyzing the microbial flora. Real-time fluorescence quantitative PCR was used to detect the expression of candidate genes in different cervical tissues, ROC curve and logistic regression was used to analyse and predict the risk factors related to the occurrence and progression of cervical intraepithelial neoplasia. Finally, the early warning model of cervical intraepithelial neoplasia occurrence and progression is established.

RESULTS

Cervical tissues from normal, cervical intraepithelial neoplasia and cervical cancer patients were collected for microbial community high-throughput 16S rDNA sequencing. The analysis revealed five different pathways related to cervical intraepithelial neoplasia. 10 candidate genes were selected by further bioinformatics analysis and preliminary screening. Real time PCR, ROC curve and Logistic regression analysis showed that human papillomavirus infection, TCT severity, ABCG2, TDG, PCNA were independent risk factors for cervical intraepithelial neoplasia. We used these indicators to establish a random forest model. Seven models were built through different combinations. The model 4 (ABCG2 + PCNA + TDG) was the best early warning model for the occurrence and progression of CIN.

CONCLUSIONS

A total of 5 differential pathways and 10 candidate genes related to occurrence and progression of cervical intraepithelial neoplasia were found in cervical microbial community. This study firstly identified the genes from cervical microbial community that play an important role in the occurrence and progression of cervical intraepithelial neoplasia. At the same time, the early warning model including ABCG2 + PCNA+TDG genes provided a new idea and target for clinical prediction and blocking the evolution of cervical intraepithelial neoplasia malignant transformation from the aspect of cervical microbiological related genes.

Evaluation of Telomerase (hTert), Ki67 and p16ink4a expressions in low and high-grade cervical intraepithelial lesions

Objective

to study the association between the histological grading of cervical intraepithelial neoplasia (CIN I, CIN II and CIN III) and the immunohistochemical expression for p16ink4a, hTert and Ki67, as well as to evaluate the relationship of these markers with the risk of recurrence after surgical treatment.

Methods

we studied a historical cohort of 94 women with intraepithelial lesions CIN I (low grade), CIN II and CIN III (high grades) submitted to conization or electrosurgical excision of the transformation zone. We evaluated all surgical specimens for immunohistochemical expression of p16ink4a, hTert and Ki67.

Results

the mean age was 38.2 years; p16ink4a was absent in most CIN I cases. In patients with CIN II or I/II (association of low and high-grade lesions), we observed p16ink4a ≤10%. In patients with CIN III, we found a higher expression frequency of p16ink4a >50%. In CIN I, the majority had Ki67≤10% and low frequency of Ki67>50%. In the CIN III category, there were fewer patients with Ki67≤10%, and Ki67 was absent in most patients of CIN II and III groups. There was no association between hTert expression and histologic grade. There were no statistically significant differences between the expression of the markers in patients with and without recurrence.

Conclusion

there was a statistically significant association of p16ink4a and Ki67 with histological grade. The markers' expression, as for disease recurrence, was not statistically significant in the period evaluated.

Role of p16 testing in cervical cancer screening among HIV-infected women

BACKGROUND

p16 immunohistochemistry is used to evaluate for HPV-associated cervical intraepithelial neoplasia. The diagnostic performance of p16 in HIV infection is unclear.

METHODS

Between June-December 2009, HIV-infected women underwent Papanicolaou (Pap) smear, human papillomavirus (HPV) testing, visual inspection with acetic acid (VIA), and colposcopy-directed biopsy as the disease gold standard at a HIV clinic in Kenya. Pap smears were evaluated for p16 expression. Sensitivity, specificity, positive predictive value (PPV), and area under the receiver operating characteristic curve (AUC) of p16 to detect CIN2/3 on histology and the impact of immunosuppression and ART was assessed.

RESULTS

Of 331 cervical samples with p16 expression, p16 sensitivity and specificity to detect CIN2/3 was 54.1% and 72.4% respectively, which was lower than Pap and HPV in sensitivity, but higher in specificity than Pap, HPV, and VIA. Combining tests and p16 reduced sensitivity and increased specificity of Pap from 90.5% to 48.7% and 51.4% to 81.7%; of VIA from 59.5% to 37.8% and 67.6% to 89.9%; and of HPV from 82.4% to 50.0% and 55.3% to 84.8%. Combination p16 increased the PPV of Pap from 34.9% to 43.4%; of HPV from 34.7% to 48.7%; and VIA from 34.9% to 51.9%. Adjunctive p16 did not change AUC (P>0.05). P16 performance was not altered by immunosuppression or ART use. Combining p16 with HPV and VIA reduced the variation in HPV and VIA performance associated with CD4 and ART.

CONCLUSION

As an adjunctive test in HIV-infected women, p16 immunohistochemistry increased specificity and PPV of HPV and VIA for CIN2/3, and was not altered in performance by immunosuppression, ART, or age.

Comparison Between Two Detection Methods for HPV16, HPV18 and P16Ink4a Biomarkers in Diagnosis of Abnormal Cervical Cytology

Background:

Cervical cancer is the second most common cancer among women in many populations. While the Pap smear is a well established screening test it suffers from both false-positive and false-negative results in diagnosis of cancers and precancerous states. In this study, immunocytochemistry of the P16 biomarker and HPV-PCR were compared for their diagnostic potential.

Materials and methods:

In the study, we obtained pairs of specimens from 45 women with cervical dysplasia. One sample was placed in a liquid-based solution, and processed for staining of sections with antibodies to P16. HPV-PCR was performed on the other and the results obtained were analyzed by T-test using SPSS v. 15.

Results:

Using HPV-PCR 71% of the samples were found to be infected with either HPV 16 or HPV 18, and the rate of infection did not have a statistically significant relationship with higher grades of dysplasia (p= 0.253). In contrast, with immunocytochemistry evaluation of P16, 64% of the specimens were positive, but the percentage of positive results significantly increased with higher grades of dysplasia (p= 0.0001).

Conclusion:

Employment of the P16 marker as an optional test might be preferable over HPV-PCR for cervical dysplasia in our geographical region.

Werner syndrome through the lens of tissue and tumour genomics

Werner syndrome (WS) is the canonical adult human progeroid ('premature aging') syndrome. Patients with this autosomal recessive Mendelian disorder display constitutional genomic instability and an elevated risk of important age-associated diseases including cancer. Remarkably few analyses of WS patient tissue and tumors have been performed to provide insight into WS disease pathogenesis or the high risk of neoplasia. We used autopsy tissue from four mutation-typed WS patients to characterize pathologic and genomic features of WS, and to determine genomic features of three neoplasms arising in two of these patients. The results of these analyses provide new information on WS pathology and genomics; provide a first genomic characterization of neoplasms arising in WS; and provide new histopathologic and genomic data to test several popular models of WS disease pathogenesis.

Mucosal alpha-papillomaviruses are not associated with esophageal squamous cell carcinomas: Lack of mechanistic evidence from South Africa, China and Iran and from a world-wide meta-analysis

Epidemiological and mechanistic evidence on the causative role of human papillomaviruses (HPV) in esophageal squamous cell carcinoma (ESCC) is unclear. We retrieved alcohol- and formalin-fixed paraffin-embedded ESCC tissues from 133 patients seropositive for antibodies against HPV early proteins, from high-incidence ESCC regions: South Africa, China and Iran. With rigorous care to prevent nucleic acid contamination, we analyzed these tissues for the presence of 51 mucosotropic human alpha-papillomaviruses by two sensitive, broad-spectrum genotyping methods, and for the markers of HPV-transformed phenotype: (i) HPV16/18 viral loads by quantitative real-time PCR, (ii) type-specific viral mRNA by E6*I/E6 full-length RT-PCR assays and (iii) expression of cellular protein p16(INK4a). Of 118 analyzable ESCC tissues, 10 (8%) were positive for DNA of HPV types: 16 (4 tumors); 33, 35, 45 (1 tumor each); 11 (2 tumors) and 16, 70 double infection (1 tumor). Inconsistent HPV DNA+ findings by two genotyping methods and negativity in qPCR indicated very low viral loads. A single HPV16 DNA+ tumor additionally harbored HPV16 E6*I mRNA but was p16(INK4a) negative (HPV16 E1 seropositive patient). Another HPV16 DNA+ tumor from an HPV16 E6 seropositive patient showed p16(INK4a) upregulation but no HPV16 mRNA. In the tumor tissues of these serologically preselected ESCC patients, we did not find consistent presence of HPV DNA, HPV mRNA or p16(INK4a) upregulation. These results were supported by a meta-analysis of 14 other similar studies regarding HPV-transformation of ESCC. Our study does not support the etiological role of the 51 analyzed mucosotropic HPV types in the ESCC carcinogenesis.

Grading of atypia in genital skin lesions: routine microscopic evaluation and use of p16 immunostaining

BACKGROUND

p16 immunostaining has been used to aid and improve the histopathologic evaluation of equivocal cervical lesions with associated low-grade or high-grade dysplasia. However, the utility of p16 immunostaining in the diagnosis of atypical genital skin lesions remains debatable.

METHODS

We conducted a cross-sectional study of genital skin lesions with varying degrees of atypia. Four pathologists assessed lesional atypia and interpreted hematoxylin and eosin (H&E) staining and p16 immunostaining without knowledge of original diagnosis. Our primary outcomes were diagnostic agreement and test performance of p16 immunostaining compared to consensus H&E diagnosis.

RESULTS

Our sample was comprised of 23 cases of atypical genital skin lesions. p16 immunostaining was negative in all cases of reactive atypia (n = 3) and the majority (n = 7 of 8; 88%) of low-grade squamous intraepithelial lesions (LSILs). The majority (n = 10 of 12; 83%) of high-grade squamous intraepithelial lesions (HSIL) were p16 positive. Diagnostic agreement for histopathologic assessment using H&E staining was moderate (kappa = 0.44), while inter-observer agreement of p16 immunostaining was excellent (kappa = 0.87). Compared to consensus diagnosis using H&E staining, p16 immunostaining performed well (sensitivity 83.3%; specificity 90.9%).

CONCLUSIONS

p16 immunostaining may be a useful adjunctive marker for assessing dysplasia in genital skin lesions and increasing diagnostic agreement among pathologists.

P16INK4A and survivin: Diagnostic and prognostic markers in cervical intraepithelial neoplasia and cervical squamous cell carcinoma

OBJECTIVE

To explore the the correlations of p16INK4A (p16) and survivin expressions with cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma.

METHODS

The p16 and survivin expressions were detected in 50 cervical squamous cell carcinoma tissues, 150 various grades of CIN tissues and 30 normal cervical tissues using immunohistochemistry. All data were analyzed applying SPSS 17.0 software.

RESULTS

The p16 and survivin expressions showed the presence of statistical significance in cervical cancer, CINI, CINII, CINIII and normal cervical tissues (P<0.05), and the comparison also revealed statistical significance among groups (all P<0.05); the p16 and survivin expressions were positively correlated with the grade of cervical diseases (both P<0.05). Moreover, p16 protein was associated with CIN grade and lymph node metastases in cervical cancer (all P<0.05); survivin protein was also related with clinical stages, CIN grade and lymph node metastases (all P<0.05); the p16 and survivin expressions were positively correlated with cervical cancer (r=0.854, P<0.001), and associated with poor prognosis of cervical cancer.

CONCLUSION

Briefly, p16 and survivin expression may be correlated with the clinico-pathological and prognosis of cervical cancer.

p16INK4a immunohistochemical and histopathologic study of Pap test cases interpreted as HSIL without CIN2-3 identification in subsequent cervical specimens

Tissue biopsy following a pap test diagnosis of high grade squamous intraepithelial lesion (HSIL) sometimes fails to confirm the presence of a corresponding high grade cervical intraepithelial lesion (CIN 2-3), leading to confusion as to how best to manage the patient. It has been shown that these patients are still at higher risk for future detection of CIN 2-3 even if the initial biopsy fails to detect it. It has also been shown that immunohistochemical staining for p16INK4a can be reliably used as a surrogate marker for infection with high risk human papillomavirus in cervical samples, and that it can be used to enhance detection of CIN2-3 in cases where suspicion is high. To evaluate the use of p16INK4a staining in cases of HSIL which were not confirmed on initial biopsy, two pathologists rereviewed Pap and hematoxylin and eosin preparations from all such cases seen within the preceding 3 years. Immunohistochemical study for p16INK4a was performed and graded on representative sections. The results were tabulated and analyzed. Of the identified 596 HSIL Pap cases, 82% had HSIL on initial cervical specimens. Table 1 shows the 56 cases included in the study with graded and stratified p16INK4a results. On review of the p16INK4a slides, only 2 cases could be upgraded to HSIL/CIN2-3 from the original diagnosis. p16INK4a 2-3+ was expressed more frequently in cases initially interpreted on Pap as low-grade cervical lesion as compared with benign (24 of 35 cases). In the younger than 24-yr-old group p16 2-3+ reactivity was more frequent in benign and low-grade cervical lesion/CIN1 groups (benign: 3 of 5 cases, and CIN1: 6 of 8), and p16 negative reactivity was not seen. p16INK4a was graded 0-1+ more frequently in specimens interpreted as benign in the older than 25 yr olds (10 of 16 cases). The study suggests some diagnostic benefit from the use of p16INK4a immunohistochemical study on cervical specimens from women with a HSIL Pap test without HSIL/CIN2-3 on original hematoxylin and eosin review.

Methylated ZNF582 gene as a marker for triage of women with Pap smear reporting low-grade squamous intraepithelial lesions - a Taiwanese Gynecologic Oncology Group (TGOG) study

OBJECTIVE

Our previous work revealed that host genes ZNF582, PTPRR, PAX1, and SOX1 are highly methylated in cervical intraepithelial neoplasias grade 3 or worse (CIN3(+)). In this study, we used a standardized testing assay to evaluate the clinical efficacy of these biomarkers in the triage of cytological diagnoses of low-grade squamous intraepithelial lesions (LSILs), and compared the performance with human papillomavirus (HPV) testing.

METHODS

This 2-year multicenter prospective study examined a population of 230 women from 12 medical centers who were diagnosed with LSILs on cervical cytology. Cervical scrapings were obtained prior to a colposcopy-directed biopsy for quantitative methylation analysis of ZNF582, PTPRR, PAX1, and SOX1, and HPV testing. Using logistic regression and receiver operating characteristic curve analyses, the abilities of methylated genes and HPV to predict CIN3(+) were assessed.

RESULTS

Fifteen (6.5%) of the 230 women with a cytological diagnosis of LSIL were confirmed to have CIN3(+) after a colposcopy-directed biopsy. Among the 4 methylated genes, ZNF582 was found to be the best biomarker for detecting CIN3(+). The sensitivities for methylated ZNF582 and HPV testing were 73% and 80%, and the specificities were 71% and 28%, respectively. The odds ratio for predicting CIN3(+) using methylated ZNF582 was 6.8 (95% confidence interval (CI) 2.1-22.1), which was much better than HPV testing (OR=1.6, 95% CI 0.4-5.8).

CONCLUSION

This is the first study to show that ZNF582 methylation analysis of cervical swabs may be a promising choice in the positive triage of cytological diagnoses of LSILs.

P16(INK4A) immunostaining is a strong indicator for high-risk-HPV-associated oropharyngeal carcinomas and dysplasias, but is unreliable to predict low-risk-HPV-infection in head and neck papillomas and laryngeal dysplasias

Human papillomavirus (HPV) is a risk factor for the development of benign and malignant mucosal head and neck lesions. P16(INK4A) is often used as a surrogate marker for HPV-infection, although there is still controversy with respect its reliability. Our aim was to determine if p16(INK4A) overexpression can accurately predict both high-risk and low-risk-HPV-presence in (pre)malignant and benign head and neck lesions. P16(INK4A) immunohistochemistry was performed on paraffin-embedded tissue sections of 162 oropharyngeal squamous cell carcinomas (OPSCC), 14 tonsillar and 23 laryngeal dysplasias, and 20 tonsillar and 27 laryngeal papillomas. PCR, enzyme-immunoassay and FISH analysis were used to assess HPV-presence and type. Of the 162 OPSCC and 14 tonsillar dysplasias, 51 (31%) and 10 (71%) were HPV16-positive, respectively. All tonsillar papillomas were HPV-negative and four laryngeal dysplasias and 26 laryngeal papillomas were positive for HPV6 or -11. P16(INK4A) immunohistochemistry revealed a strong nuclear and cytoplasmic staining in 50 out of 51 HPV16-positive and 5 out of 111 HPV-negative OPSCC (p < 0.0001) and in all HPV16-positive tonsillar dysplasias, whereas highly variable staining patterns were detected in the papillomas and laryngeal dysplasias, irrespective of the HPV-status. In addition, the latter lesions generally showed a higher nuclear than cytoplasmic p16(INK4A) immunostaining intensity. In conclusion, our data show that strong nuclear and cytoplasmic p16(INK4A) overexpression is a reliable surrogate indicator for HPV16 in OPSCC and (adjacent) dysplasias. For HPV6 or -11-positive and HPV-negative benign and premalignant lesions of the tonsil and larynx, however, p16(INK4A) immunostaining is highly variable and cannot be recommended to predict HPV-presence.

The Utility of Immunohistochemistry for Providing Genetic Information on Tumors

With advances in immunohistochemical technology and growing knowledge of the molecular genetics of tumors, immunohistochemistry is playing an increasingly important role in providing genetic information for tumors. Specific chromosomal translocations can be demonstrated through detection of the protein product of one of the genes involved in gene fusion (such as BCL2, cyclin D, and ALK). Some mutations can be detected by (1) aberrant localization of the protein product (such as β-catenin and nucleophosmin), (2) abnormal accumulation of the protein product as a result of stabilization of the protein (such as p53), and (3) mutation-specific antibodies directed against the mutant protein (such as isocitrate dehydrogenase gene R132H mutation, epidermal growth factor receptor gene L858R and exon 19 deletion mutations, and BRAF gene V600E mutation). Gene deletion or loss of function can be demonstrated by the loss of immunostaining for the protein product (such as mismatch repair proteins in microsatellite-unstable tumors, E-cadherin in lobular carcinoma of the breast, and INI1 in rhabdoid tumors, atypical teratoid/rhabdoid tumors, and epithelioid sarcomas). Gene amplification can be demonstrated by overexpression of the protein product (such as HER2 in breast and gastric cancers, and MDM2 or CDK4 in well-differentiated/dedifferentiated liposarcomas). Viruses associated with tumors can be demonstrated directly (such as Epstein-Barr virus latent membrane protein-1 in Hodgkin lymphomas, human herpesvirus 8 in Kaposi sarcomas, and Merkel cell polyomavirus in Merkel cell carcinomas) or by a surrogate marker (such as p16 in human papillomavirus infection). In this review, examples are given to illustrate the principles and pitfalls of these applications.

Cell cycle suppressor proteins are not related to HPV status or clinical outcome in patients with vulvar carcinoma

Interactions between the cyclin-dependent kinase inhibitors (CDKI) and human papillomavirus (HPV) infection in the pathogenesis of vulvar carcinoma are still incomplete. This study aimed to evaluate the prognostic relevance of these proteins in vulvar cancer. One hundred and thirty-nine patient specimens assembled in a tissue microarray were evaluated for p16, p21, p27, and pRb by immunohistochemistry. HPV status was assessed by a linear array HPV genotyping test. In 16 cases with available frozen tumor, quantitative real-time reverse transcriptase-polymerase chain reaction for CDKN2A(p16), CDKN1A, and Rb was performed. Protein expression was considered positive in 40 patients for p16, 35 for p21, 28 for p27, and 19 for pRb. HPV was positive in 43 of the 105 evaluable cases. Expression of CDKIs and pRb, with the exception of p16, seem to be linked to the early phases of vulvar carcinogenesis. Although p16 and p21 protein expression was associated with early stages of disease, no prognostic significance was found when analyzing CDKI proteins or detecting HPV status, limiting their clinical usage. No association was observed between expression of CDKI proteins and HPV status, suggesting that in spite of this association found in cervical cancer, this seems not to be valid for vulvar carcinoma.

Post-cervical conization outcomes in patients with high-grade intraepithelial lesions

To investigate the rates of residual, recurrent and invasive disease after cervical conization in patients diagnosed with cervical intraepithelial neoplasia (CIN) grades 2/3. A retrospective study was conducted with 274 patients undergoing cervical conization due to diagnosis of CIN 2/3. Cervical conization was done through the Loop Electrosurgical Excision Procedure (LEEP) and Cold Knife Conization. Data related to personal, familial, gynecological, and obstetric antecedents, as well as surgical specimens margins were collected from medical records. The outcome after conization was evaluated, including the time of follow-up and disease recurrence. The outcome after conization was not associated with age of menarche (p = 0.920), age of the first sexual intercourse (p = 0.533), number of parturition (p = 0.063), number of sexual partners (p = 0.328), immunosuppression (p = 0.225), smoking habit (p = 0.193), and conization type (p = 0.198). However, the outcome presented a significant association with age (p < 0.001), pregnancy numbers (p = 0.009), use of hormonal contraception methods (p = 0.016), menopause (p = 0.007), type of margins (p = 0.011), and cone histological results (p = 0.030). The routine control of all patients who had undergone cervical conization is obligate, independently of surgical margins, due to the risk of disease recurrence; the older patients and those with CIN 3 should have a more rigorous follow-up.

Laboratory management of cervical intraepithelial neoplasia: proposing a new paradigm

Since the discovery of human papillomavirus (HPV) type 16 in early 80s, the link between HPV and cervical cancer has been established with certainty, a function of the discovery and cloning of a range of HPV types associated with both cancer precursors (cervical intraepithelial neoplasia or CIN) and carcinomas and extensive epidemiologic, clinical, pathologic, and experimental data. These accumulated results have culminated in new paradigms of cancer prevention through screening and triage. Despite this, the management of women with CIN is still suboptimal and the overtreatment of these conditions still occurs, largely due to the lack of clarity regarding which precancerous lesions are most likely to progress in grade. Recently, a discrete population of cuboidal cells was discovered at the cervical squamocolumnar junction, the anatomic site where the large majority of HPV-related (pre)neoplastic lesions develop. These cells seem to be embryonic in nature and participate both in benign metaplasias and the initial phase of precancer development. This review summarizes the historical evolution of precursor management, assesses the potential role of this and other discoveries in segregating lower from higher-risk precursors, and examines their potential impact on the management of women with real or potential cervical cancer precursors.

Deregulation of p27 and cyclin D1/D3 control over mitosis is associated with unfavorable prognosis in non-small cell lung cancer, as determined in 405 operated patients

INTRODUCTION

A large group of interacting molecular factors, involved in epithelial-mesenchymal transition, epidermal growth factor receptor (EGFR) signaling, and G1 mitotic phase, are shown to play an important role in cancerogenesis and progression of non-small cell lung cancer (NSCLC). Since success concerning potential correlations, structural and numeric gene aberrations, and biological risk assessment of these molecular factors are still lacking, combined analysis of a multitude of intertwined factors is currently a promising approach.

METHODS

Cyclins (D1, D2, D3, and E), p21, p27, EGFR, Snail, E-cadherin, beta-catenin, phosphatidylinositol-3' kinase, phosphatase and tensin homologue, phosphorylated Akt, and phosphorylated signal transducer, and activator of transcription-3 were analyzed by immunohistochemistry in 405 surgically resected NSCLC, using a standardized tissue microarray platform. In addition, the gene status of EGFR and cyclin D1 was examined by fluorescence in situ hybridization. Extensive clinical data were acquired, enabling detailed clinicopathologic correlation during a postoperative follow-up period of up to 14 years.

RESULTS

The protein overexpressions of nuclear p27, cyclin D1, cyclin D3, E-cadherin, and EGFR as assessed by immunohistochemistry were all associated with a significant reduction in overall survival time. In addition, cyclin D1 proved especially important, being the only independent molecular tumor-related factor with prognostic significance by multivariable analysis. In analogy to EGFR, recurrent numeric gene aberrations, particularly high-level amplifications, of cyclin D1 were obvious.

CONCLUSIONS

The results emphasize that deregulation of controlling factors of the early G1 phase is of significant oncogenic relevance and may represent a potential treatment target in NSCLC.

Diagnostic role of p16/INK4A protein in Human Papillomavirus (HPV) induced cervical dysplasia

The p16/INK4A protein is a cellular regulatory polypeptide over-expressed in the presence of high levels of the Human Papillomavirus (HPV) coded E7 protein. This review outlines the use of p16 antigen staining in cervical biopsies as well as in PAP smears summarizing the corresponding literature and commenting the authors’ own experience. The p16 antigen is a reliable marker for dysplastic cells in CINII/CINIII (HSIL) lesions as viewed in cervical biopsies. When PAP smears were examined at large scale screening for p16 antigenreactive and atypical cells, considerable variations could be found especially in ASCUS graded lesions. Therefore, the presence of p16-reactive atypical cells in PAP smears should be interpreted together with the cytological signs of dysplasia, such as the altered N/C ratio. In addition, women revealing p16-positive ASCUS/LSIL specimens should be examined for the presence of HPV DNA. Detection of HPV DNA alone, i.e. in the absence of cytological screening has a low predictive value, since the clearance of HPV may occur even in the absence of morphological alterations. Combined cytological as well as molecular follow up contributes to the efficiency of diagnostic and increases the probability of correct interpretation of the pre-cancerous lesions by non-invasive techniques.

Primary signet-ring cell carcinoma of the cervix: case report and review of the literature

Mucinous adenocarcinoma of the cervix has 5 subtypes: endocervical, intestinal, signet-ring cell, minimal deviation, and villoglandular. There are only rare reports of primary signet-ring cell carcinoma of the cervix in the literature. Herein we report a 53-year-old woman with cervical adenocarcinoma with signet-ring cell morphology. Thorough systemic examination did not reveal another primary focus. DNA extraction from paraffin-embedded tissue revealed the presence of human papilloma virus (HPV) type 18, which supports the cervical origin of the tumor. Signet-ring cell morphology can be observed in both benign and malignant lesions of the uterine cervix. Most of the malignant lesions are metastatic. Histological features and immunohistochemical profiles are discussed, and a review of signet-ring cell morphology in the uterine cervix is included.

Tissue transglutaminase 2 as a biomarker of cervical intraepithelial neoplasia (CIN) and its relationship to p16INK4A and nuclear factor kappaB expression

Tissue transglutaminase 2 (TG2) is a recently identified molecule with multifunctional physiological roles. This is the first report of the expression of TG2 in cervical intraepithelial neoplasia (CIN) and invasive squamous cell carcinoma (SCC). For comparison, the expression of p16, a known surrogate biomarker of HPV infection, was evaluated. The expression of nuclear factor kappa B (NF-kappaB), a molecule crucial to inflammation and neoplasia, was also determined to explore its possible linkage with TG2 expression. Twenty cases each with normal cervical histology, CIN1, CIN2, CIN3, and invasive SCC were analyzed for TG2, p16, and NF-kappaB expression by immunohistochemistry. Intergroup differences were analyzed by Friedman ANOVA. Cytoplasmic as well as nuclear TG2 expression was observed in the epithelial cells. As compared to normal controls, CIN1 showed markedly increased cytoplasmic TG2 expression (p = 0.006). In CIN2/3, additional nuclear TG2 expression was seen (p = 0.009 and 0.031, respectively). Marked extracellular stromal upregulation of TG2 was noted in CIN3/SCC versus normal controls (p = 0.054; p = 0.003). There was no relationship of TG2 with either p16 of NF-kappaB expression. Combining TG2 immunoreactivity with p16 increased the immunolabeling of dysplasia from 35% to 100% in CIN1, 45% to 60% in CIN2, and 60% to 85% in CIN3. TG2 serves as an additional biomarker for all grades of cervical dysplasia, especially for low-grade dysplasia.

Large-scale analysis of protein expression changes in human keratinocytes immortalized by human papilloma virus type 16 E6 and E7 oncogenes

Background

Infection with high-risk type human papilloma viruses (HPVs) is associated with cervical carcinomas and with a subset of head and neck squamous cell carcinomas. Viral E6 and E7 oncogenes cooperate to achieve cell immortalization by a mechanism that is not yet fully understood. Here, human keratinocytes were immortalized by long-term expression of HPV type 16 E6 or E7 oncoproteins, or both. Proteomic profiling was used to compare expression levels for 741 discrete protein features.

Results

Six replicate measurements were performed for each group using two-dimensional difference gel electrophoresis (2D-DIGE). The median within-group coefficient of variation was 19–21%. Significance of between-group differences was tested based on Significance Analysis of Microarray and fold change. Expression of 170 (23%) of the protein features changed significantly in immortalized cells compared to primary keratinocytes. Most of these changes were qualitatively similar in cells immortalized by E6, E7, or E6/7 expression, indicating convergence on a common phenotype, but fifteen proteins (~2%) were outliers in this regulatory pattern. Ten demonstrated opposite regulation in E6- and E7-expressing cells, including the cell cycle regulator p16^INK4a; the carbohydrate binding protein Galectin-7; two differentially migrating forms of the intermediate filament protein Cytokeratin-7; HSPA1A (Hsp70-1); and five unidentified proteins. Five others had a pattern of expression that suggested cooperativity between the co-expressed oncoproteins. Two of these were identified as forms of the small heat shock protein HSPB1 (Hsp27).

Conclusion

This large-scale analysis provides a framework for understanding the cooperation between E6 and E7 oncoproteins in HPV-driven carcinogenesis.

p16 expression in conventional and desmoplastic trichilemmomas

The expression of p16 in cutaneous neoplasms is upregulated in melanocytic neoplasms, ultraviolet radiation-induced neoplasms, such as actinic keratoses and squamous cell carcinomas, and in lesions related to human papillomavirus, such as Bowen's disease and bowenoid papulosis. In cervical dysplasia and tonsillar carcinoma, there is such a close relationship between p16 and human papillomavirus (HPV) to the extent that p16 immunostaining is used as a surrogate marker for the presence of HPV proteins. In this study we were interested in the expression pattern of p16 in trichilemmomas. Twenty-six conventional and 19 desmoplastic trichilemmomas were immunohistochemically stained for p16. p16 immunostaining was noted in the majority of conventional (80.8%) and desmoplastic trichilemmomas (73.7%). The staining pattern was both nuclear and cytoplasmic. The staining intensity was more pronounced in the desmoplastic variant. We describe for the first time p16 expression in trichilemmomas and discuss our findings in conjunction with p16 expression found in other cutaneous neoplasms. Additionally, the relationship of p16 to HPV infection is critically evaluated.

p16(INK4a) immunostaining in cytological and histological specimens from the uterine cervix: a systematic review and meta-analysis

BACKGROUND

P16(INK4a) is a biomarker for transforming HPV infections that could act as an adjunct to current cytological and histological assessment of cervical smears and biopsies, allowing the identification of those women with ambiguous results that require referral to colposcopy and potentially treatment.

MATERIAL AND METHODS

We conducted a systematic review of all studies that evaluated the use of p16(INK4a) in cytological or histological specimens from the uterine cervix. We also estimated the mean proportion of samples that were positive for p16(INK4a) in cytology and histology, stratified by the grade of the lesion.

RESULTS

Sixty-one studies were included. The proportion of cervical smears overexpressing p16(INK4a) increased with the severity of cytological abnormality. Among normal smears, only 12% (95% CI: 7-17%) were positive for the biomarker compared to 45% of ASCUS and LSIL (95% CI: 35-54% and 37-57%, respectively) and 89% of HSIL smears (95% CI: 84-95%). Similarly, in histology only 2% of normal biopsies (95% CI: 0.4-30%) and 38% of CIN1 (95% CI: 23-53%) showed diffuse staining for p16(INK4a) compared to 68% of CIN2 (95% CI: 44-92%) and 82% of CIN3 (95% CI: 72-92%).

CONCLUSION

Although there is good evidence that p16(INK4a) immunostaining correlates with the severity of cytological/histological abnormalities, the reproducibility is limited due to insufficiently standardized interpretation of the immunostaining. Therefore, a consensus needs to be reached regarding the evaluation of p16(INK4a) staining and the biomarker needs to be assessed in various clinical settings addressing specific clinical questions.

ELISA test to detect CDKN2A (p16(INK4a)) expression in exfoliative cells: a new screening tool for cervical cancer

BACKGROUND

The purpose of this study was to use an enzyme-linked immunosorbent assay (ELISA) to detect cyclin-dependent kinase inhibitor 2A (CDKN2A; also known as p16(INK4a)) in exfoliative cervical cells. CDKN2A is upregulated and considered as a surrogate marker for cervical intraepithelial neoplasia and cancer.

METHODS

Liquid-based ThinPrep((R)) cytologic test (TCT) and ELISA were performed on 1356 specimens collected prior to biopsy. A cotton swab was used to gather exfoliative cells. A sandwich ELISA was performed to measure the amount of solublized CDKN2A protein.

RESULTS

The sensitivity and specificity of the TCT for screening of cervical dysplasia and cancer were 82.93% and 88.11%, respectively. The sensitivity and specificity for measuring CDKN2A with ELISA to detect significant cervical disease were 87.80% and 92.43%, respectively. CDKN2A expression was correlated with the severity of cervical damage (r = 0.774; p < 0.001).

CONCLUSION

The sensitivity and specificity of detecting CDKN2A expression with ELISA in exfoliative cervical cells was superior to TCT (p = 0.023 and p < 0.001, respectively). These results suggest that detecting CDKN2A with ELISA has the potential to become a new screening method for cervical cancer.