Diagnostic utility of p16INK4a: a reappraisal of its use in cervical biopsies

Expression of p16 Tumor Suppressor Protein in Malignant Ovarian Germ Cell Tumors; Immunohistochemical Study

BACKGROUND

Malignant ovarian germ cell tumors represent small percentage of malignant ovarian neoplasms but they affect significantly young age group.

AIM OF THE STUDY

To investigate the immunohistochemical expression of p16 tumor suppressor protein in malignant ovarian germ cell tumors.

MATERIALS AND METHODS

Twenty-two malignant ovarian germ cell tumors (five dysgerminoma, eight immature teratoma, and nine yolk sac tumors), twenty mature cystic teratoma tumors and twenty normal ovarian tissue were immunohistochemically stained with p16 monoclonal antibody. Ki67 immunohistochemical staining was done for malignant ovarian germ cell tumors to assess proliferation.

RESULTS

We found that p16 tumor suppressor protein is overexpressed in all malignant ovarian germ cell tumors in both nuclear and cytoplasmic locations compared to control and to mature cystic teratoma (p-value <0.001). Cytoplasmic p16 expression was significantly correlated to Ki67 proliferation index in malignant ovarian germ cell tumors (p-value = 0.033, r = 0.445).

CONCLUSION

Overexpression of p16 in malignant ovarian germ cell tumors denotes that dysfunction of the cyclin dependent kinase pathway is involved in tumorigenesis of malignant ovarian germ cell tumors.

Human parvovirus B19 infection in malignant and benign tissue specimens of different head and neck anatomical subsites

BACKGROUND

The role of human parvovirus B19 (B19V) infection in malignant and benign lesions such as head and neck squamous cell carcinomas (HNSCCs) and oral mucocele lesions has not been established. Herein, we examined, for the first time, the presence of B19V in HNSCCs from Iranian subjects.

METHODS

One hundred and eight HNSCC specimens were analyzed for the presence of B19V using nested polymerase chain reaction (nPCR) and TaqMan quantitative PCR assays. Immunohistochemistry procedures were performed to evaluate the expression of B19V VP1/VP2 proteins, p16INK4a, and NF-κB in tumor tissues and their adjacent non-tumor tissues. In addition, 40 oral mucocele, 30 oral buccal mucosa swabs, and 30 nasopharyngeal swabs obtained from healthy adults were analyzed as controls.

RESULTS

B19V DNA was detected in 36.1% of HNSCCs. Further, 23.3% of HNSCC specimens showed immunoreactivity against B19V VP1/VP2 proteins. There was a significant difference in the frequency of B19V DNA-positive cases between the patient and control groups (p < 0.0001). Moreover, comparing tumoral tissues and their adjacent non-tumor tissues in terms of immunoreactivity against B19V structural proteins, a significant association was found between tumor tissues and B19V infection (p < 0.0001). Finally, investigating the simultaneous presence of B19V and high-risk human papillomaviruses (HPV) DNA, we found a significant association between these two viral infections in HNSCCs (p = 0.031).

CONCLUSIONS

To sum up, B19V was frequently present in HNSCC tissues of Iranian patients but mostly absent in the adjacent non-tumor tissues as well as oral mucocele lesions, buccal, and nasopharyngeal swabs of healthy subjects. HPV possibly contributes to B19V persistence in HNSCC tissues. Additional research is required to investigate potential etiological or cofactor roles of B19V in the development of HNSCCs.

Promotor methylation in ocular surface squamous neoplasia development: epigenetics implications in molecular diagnosis

INTRODUCTION

Cancer is heavily influenced by epigenetic mechanisms that include DNA methylation, histone modifications, and non-coding RNA. A considerable proportion of human malignancies are believed to be associated with global DNA hypomethylation, with localized hypermethylation at promoters of certain genes.

AREA COVERED

The present review aims to emphasize on recent investigations on the epigenetic landscape of ocular surface squamous neoplasia, that could be targeted/explored using novel approaches such as personalized medicine.

EXPERT OPINION

While the former is thought to contribute to genomic instability, promoter-specific hypermethylation might facilitate tumorigenesis by silencing tumor suppressor genes. Ocular surface squamous neoplasia, the most prevalent type of ocular surface malignancy, is suggested to be affected by epigenetic mechanisms, as well. Although the exact role of epigenetics in ocular surface squamous neoplasia has mostly been unexplored, recent findings have greatly contributed to our understanding regarding this pathology of the eye.

Decreased number of p16-positive senescent cells in human endometrium as a marker of miscarriage

PURPOSE

The aim of this study was to evaluate whether the number of p16-positive cells in the functional layer of the endometrium could be a useful biomarker to identify women with recurrent implantation failure (RIF) undergoing in vitro fertilization (IVF) at risk of miscarriage.

METHODS

Immunohistochemical staining was performed in 311 endometrial biopsies taken during mid-luteal phase using antibody against p16^INK4A. The percentage of p16-positive cells was determined in luminal, glandular and stromal endometrial cells. After embryo transfer, women were divided into the following groups: unsuccessful embryo implantation (n = 151), miscarriage (n = 66) and live birth (n = 94). The percentage of p16-positive cells in all endometrial compartments was compared among these groups.

RESULTS

We found that the percentages of p16-positive glandular and luminal epithelial endometrial cells were significantly higher in patients with live births compared to women with miscarriage (9.3% vs. 2.9%, P < 0.001; and 35.2% vs. 11.7%, P = 0.001, respectively). This tendency was not confirmed in thе stroma. The cut-off values with p16-positive luminal cells lower than 12.5% and p16-positive glandular cells lower than 3.2% could be predictive factors for miscarriage (AUC 0.80 and 0.79; sensitivity 71.3% and 74.5%; specificity 74.2% and 71.2%, respectively).

CONCLUSION

A decreased number of senescent p16-positive cells could be involved in the implantation failures and aetiology of recurrent miscarriage. Women with history of RIF with reduced populations of p16-positive cells in the endometrial glandular and luminal epithelium may be at greater risk for unsuccessful implantation and miscarriage. The percentage of p16-positive luminal epithelial cells may be clinically useful as a biomarker of miscarriage.

Human papillomavirus infection in esophageal squamous cell carcinoma and esophageal adenocarcinoma: a concise review

The causal link between high-risk human papillomavirus (hr-HPV) infection and cervical, anogenital, and some oropharyngeal malignancies has been established by both molecular and epidemiological data. The association between HPV and esophageal squamous cell carcinoma (ESCC) remains controversial, as is the true prevalence of HPV infection in ESCC. The wide range in reported rates reflects variability in the primary literature, with some larger scale case-control studies suggesting the infection rates range from 0% to 78%. Interactions between HPV and the Barrett's metaplasia-dysplasia-carcinoma sequence have been explored, and these studies have shown some conflicting data. Overall, systematic reviews have reported the prevalence of HPV-positive DNA in esophageal adenocarcinoma patients of between 13% and 35%. Postulated reasons for discrepancies in HPV prevalence rates in esophageal cancer include variations in testing methodology and assay sensitivities; technical issues, including the lack of a gold-standard primer; types of specimens utilized (fresh-frozen versus formalin-fixed tissue); geographical variation; cross-contamination; and small sample sizes. Thus, efforts must be undertaken to (1) standardize HPV testing, ideally in a central laboratory and utilizing tests that detect viral transcriptional activity; (2) avoid cross-contamination; and (3) recruit large numbers of patients to accurately ascertain HPV rates in esophageal malignancy.

Grading immunohistochemical markers p16INK4a and HPV E4 identifies productive and transforming lesions caused by low- and high-risk HPV within high-grade anal squamous intraepithelial lesions

OBJECTIVES

Because current guidelines recognise high-grade anal squamous intraepithelial lesions (HSILs) and low-grade SILs (LSILs), and recommend treatment of all HSILs although not all progress to cancer, this study aims to distinguish transforming and productive HSILs by grading immunohistochemical (IHC) biomarkers p16INK 4a (p16) and E4 in low-risk human papillomavirus (lrHPV) and high-risk (hr)HPV-associated SILs as a potential basis for more selective treatment.

METHODS

Immunostaining for p16 and HPV E4 was performed and graded in 183 biopsies from 108 HIV-positive men who have sex with men. The causative HPV genotype of the worst lesion was identified using the HPV SPF10-PCR-DEIA-LiPA25 version 1 system, with laser capture microdissection for multiple infections. The worst lesions were scored for p16 (0-4) to identify activity of the hrHPV E7 gene, and panHPV E4 (0-2) to mark HPV production and life cycle completion.

RESULTS

There were 37 normal biopsies, 60 LSILs and 86 HSILs, with 85% of LSILs caused by lrHPV and 93% of HSILs by hrHPV. No normal biopsy showed E4, but 43% of LSILs and 37% of HSILs were E4 positive. No differences in E4 positivity rates were found between lrHPV and hrHPV lesions. Most of the lesions caused by lrHPV (90%) showed very extensive patchy p16 staining; p16 grade in HSILs was variable, with frequency of productive HPV infection dropping with increasing p16 grade.

CONCLUSIONS

Combined p16/E4 IHC identifies productive and nonproductive HSILs associated with hrHPV within the group of HSILs defined by the Lower Anogenital Squamous Terminology recommendations. This opens the possibility of investigating selective treatment of advanced transforming HSILs caused by hrHPV, and a 'wait and see' policy for productive HSILs. What's already known about this topic? For preventing anal cancer in high-risk populations, all patients with high-grade squamous intraepithelial lesions (HSILs) are treated, even though this group of lesions is heterogeneous, the histology is variable and regression is frequent. What does this study add? By adding human papillomavirus (HPV) E4 immunohistochemistry to p16 INK4a (p16), and grading expression of both markers, different biomarker expression patterns that reflect the heterogeneity of HSILs can be identified. Moreover, p16/E4 staining can separate high-risk HPV-associated HSILs into productive and more advanced transforming lesions, providing a potential basis for selective treatment.

Is human papillomavirus and p16 expression associated with survival outcomes in nasopharyngeal cancer?: A systematic review and meta-analysis

INTRODUCTION

Human papillomavirus (HPV) is a known prognostic indicator in oropharyngeal cancer. Not much is known about the prognostic role of HPV in Nasopharyngeal cancer (NPC). Here, we performed a systematic review and meta-analysis of the literature to investigate if HPV status was a prognostic factor for NPC.

METHODS

PubMed (via the web), Embase, Scopus, and the Cochrane Library were searched. A systematic review and meta-analysis was done to generate the pooled Hazard Ratios (HR) for Overall Survival (OS).

RESULTS

A total of 7 studies from 2014 to 2018, reporting data on 2646 patients (range 43-1328) were included in this meta-analysis. The pooled data showed that HPV/p16 status was not associated with OS in NPC with HR of 0.77 (95% CI: 0.55-1.09, p = 0.14). The test for heterogeneity showed little to no heterogeneity of results (I² = 4%, p = 0.38). Subgroup analysis showed that in large sample sizes, HPV was significantly associated with survival.

CONCLUSION

Despite the finding in the pooled HR, we could not draw a definitive conclusion as to the prognostic significance of HPV in NPC. Recommendations for future research are given.

p16INK4a overexpression as a predictor of survival in ocular surface squamous neoplasia

AIMS

To evaluate the expression and methylation status of the p16^INK4a gene in early and advanced American Joint Committee on Cancer (AJCC) stages of ocular surface squamous neoplasia (OSSN) and to correlate its association with clinicopathological features and survival.

METHODS

Sixty-four (35 early and 29 advanced AJCC stage) patients with OSSN formed part of this study and were followed up for 36-58 (mean 48±3.6) months. Immunohistochemical expression of the p16^INK4a protein and methylation status of the p16^INK4a gene were determined by methylation-specific PCR.

RESULTS

Overexpression of p16^INK4a was observed in 18/64 (28%) and hypermethylation in 35/64 (54.7%) OSSN cases. A gradual significant increase in the expression of p16^INK4a (0%-48%, P=0.03) and decrease in its methylation (75%-16%, P=0.001) was observed with disease progression from early to advanced tumour stage. Overexpression of p16^INK4a was significantly associated with palpebral location and diffuse growth pattern in both early and advanced T stage. Hypermethylation of p16^INK4a was significantly associated with history of longer sunlight exposure in both early and advanced T stage of OSSN cases. In advanced T stage, p16^INK4a overexpression was associated with reduced disease-free survival (P=0.02) and poor prognosis (HR, 0.2; P=0.03).

CONCLUSIONS

OSSN patients presenting at an advanced AJCC stage with p16^INK4a overexpression may require more aggressive treatment. Epigenetic inactivation of the p16^INK4a gene due to sunlight exposure could be responsible for pathogenesis of OSSN.

Loss of pRB in Conjunctival Squamous Cell Carcinoma: A Predictor of Poor Prognosis

Conjunctival squamous cell carcinoma (SCC) is the most common tumor of conjunctival epithelium. It is associated with risk of permanent visual impairment and has the capability to recur, metastasize, and cause death. Deregulation of cell cycle control has been reported in a number of malignancies. The aim of the present study was to assess expression of G1/S cell cycle regulatory proteins [retinoblastoma protein (pRb)/P16/cyclin D1] in conjunctival SCC. Forty-four prospective cases of conjunctival SCC from a tertiary eye care referral center in northern India were included in this study. American Joint Committee on Cancer (AJCC) staging was performed and patients were followed up for 46±3.2 months. pRb loss was seen in 87% and overexpression of p16 and cyclin D1 in 36% and 66%, respectively. Kaplan-Meier analysis revealed reduced disease-free survival in patients with pRb loss (P=0.006). On univariate analysis, pRb loss (P=0.02), orbital invasion (P=0.03), and AJCC stage ≥T3 (P=0.03) emerged as significant high-risk features. On multivariate analysis pRb loss emerged as the most significant poor prognostic indicator in conjunctival SCC cases. Our findings suggest pRb loss to be a useful indicator of aggressive behavior and is recommended for identifying high-risk conjunctival SCC patients.

Stromal p16 expression is significantly increased in malignant ovarian neoplasms

Alterations in p16 protein expression have been reported to be associated with tumor development and progression. However, p16 expression status in the peritumoral stroma has been rarely investigated. We investigated the stromal p16 expression in ovarian neoplasms using immunohistochemistry, and differences in the expression status depending on the degree of malignancy and histological type were analyzed. This study included 24, 21, and 46 cases of benign, borderline, and malignant ovarian lesions, respectively, of which 29, 25, and 32 cases were serous, mucinous, and endometriosis-associated lesions. Most benign lesions showed negative or weak expression, whereas borderline lesions showed focal, moderate expression. Malignant lesions showed markedly elevated stromal p16 expression compared with benign or borderline lesions. There were significant differences in stromal p16 expression between benign and borderline lesions (P < 0.001) and between borderline and malignant lesions (P < 0.001). These significances remained when analysis was performed based on lesion classification as serous, mucinous, and endometriosis-associated. In contrast, differences in stromal p16 expression among the histological types were not significant. Stromal p16 expression in ovarian neoplasms was absent or weak in benign and focal, moderate in borderline lesions, whereas malignant lesions exhibited diffuse, moderate-to-strong p16 immunoreactivity. Our observations suggest that stromal p16 expression is involved in the development of ovarian carcinoma. Further studies are necessary to confirm our preliminary results.

Stromal p16 expression is significantly increased in endometrial carcinoma

p16 is a negative regulator of cell proliferation and is considered a tumor suppressor protein. Alterations in p16 protein expression are associated with tumor development and progression. However, the p16 expression status in the peritumoral stroma has not been investigated in the endometrium. Therefore, we evaluated stromal p16 expression in different types of endometrial lesions using immunohistochemistry. Differences in the p16 expression status according to the degree of malignancy and histological type were analyzed. This study included 62, 26, and 36 cases of benign, precancerous, and malignant endometrial lesions, respectively. Most benign lesions showed negative or weak expression, whereas precancerous lesions showed a variable degree of staining proportion and intensity. Atypical hyperplasia/endometrial intraepithelial neoplasia (AH/EIN) and serous endometrial intraepithelial carcinoma (SEIC) had significantly higher stromal p16 expression levels than benign lesions. Endometrioid carcinoma (EC), serous carcinoma (SC), and carcinosarcoma showed significantly elevated stromal p16 expression levels compared with benign and precancerous lesions. In addition, there were significant differences in stromal p16 expression between AH/EIN and SEIC and between EC and SC. In contrast, differences in stromal p16 expression among nonpathological endometrium, atrophic endometrium, endometrial polyp, and hyperplasia without atypia were not statistically significant. Our observations suggest that stromal p16 expression is involved in the development and progression of endometrial carcinoma, and raise the possibility that p16 overexpression in the peritumoral stroma is associated with aggressive oncogenic behavior of endometrial SC.

P16ink4a Subcellular Expression Patterns in Colorectal Adenocarcinoma, Adenoma and Non-Neoplastic Tissue Samples

Background: Colorectal cancer (CRC) is one of the most common neoplasms with high mortality at advanced stages worldwide. Thus diagnosis of CRC at an early stage with sensitive molecular methods is a high priority. The aim of this study was to evaluate P16ink4a subcellular expression patterns in colorectal adenocarcinoma, adenoma and non-neoplastic tissue samples. Methods: A total of 137 colorectal formalin fixed paraffin-embedded tissue blocks from the pathology archives of Ali-Ebne-Abitaleb central hospital, Zahedan, Iran, were examined in three groups: adenocarcinoma (n= 63), adenoma (n= 38) and non-neoplastic (n= 36). The subcellular expression pattern was determined by immunocytochemistry. Data analysis was performed using Kruskal-Wallis and Fisher exact tests with the significance level set as p˂0.05. Results: P16ink4a subcellular localization was observed in three different patterns, nuclear+cytoplasmic (73.33%), cytoplasmic (13.33%) and nuclear (13.33%). In most samples, nuclear+cytoplasmic was the predominant subcellular pattern. However, a significant difference in P16ink4a subcellular expression patterns was observed along the non-neoplastic, adenoma, adenocarcinoma sequence (p˂0.001). An association with the histological tumor type was also noted (p=0.021). Conclusion: Considering variation in localization of P16ink4a under different pathological conditions, P16ink4a night be sensitive prognostic biomarker for benign colon lesions. Its use may improve strategies for screening, prognostic assessment and management of patients with CRC. Further studies are recommended in this field.

Consolidation of molecular testing in clinical virology

INTRODUCTION

The development of quantitative methods for the detection of viral nucleic acids have significantly improved our ability to manage disease progression and to assess the efficacy of antiviral treatment. Moreover, major advances in molecular technologies during the last decade have allowed the identification of new host genetic markers associated with antiviral drug response but have also strongly revolutionized the way we see and perform virus diagnostics in the coming years. Areas covered: In this review, we describe the history and development of virology diagnostic methods, dedicating particular emphasis on the gradual evolution and recent advances toward the introduction of multiparametric platforms for the syndromic diagnosis. In parallel, we outline the consolidation of viral genome quantification practice in different clinical settings. Expert commentary: More rapid, accurate and affordable molecular technology can be predictable with particular emphasis on emerging techniques (next generation sequencing, digital PCR, point of care testing and syndromic diagnosis) to simplify viral diagnosis in the next future.

Human Papillomavirus Genotyping and p16(INK4a) Expression in Cervical Lesions: A Combined Test to Avoid Cervical Cancer Progression

Cervical cancer is a major public health problem in Morocco. The cervical cancer has a long precancerous period that provides an opportunity for the screening and treatment. Improving screening tests is a priority goal for the early diagnosis of cervical cancer. This study was conducted to evaluate the combination of p16(INK4a) protein expression, human papillomavirus (HPV) typing, and histopathology for the identification of cervical lesions with high risk to progress to cervical cancer among Moroccan women. A total of 96 cervical biopsies were included in this study. Signal amplification in situ hybridization with biotinylated probes was used to detect HPV. Immunohistochemistry was used to evaluate the expression of p16(INK4a) protein. HPV DNA was detected in 74.0% of the biopsies (71/96). Of the seventy-one positive HPV cases, we detected 67.6% (48/71) of high risk (HR)-HPV (HPV 16 and 18), 24% of low risk-HPV (HPV 6 and 11), 1.4% intermediate risk-HPV (HPV 31, 33, and 35), and 7% coinfections (HPV 6/11 and 16/18). Overexpression of p16(INK4a) protein was observed in 72.9% (70/96) of the biopsies. In addition, p16(INK4a) protein detection was closely correlated with recovery of HR HPV. Our result showed that p16(INK4a) expression level is correlated with HR-HPV status.

Overdiagnosis of HSIL on cervical biopsy: errors in p16 immunohistochemistry implementation

In 2012, the lower anogenital squamous terminology (LAST) project introduced new nomenclature for human papillomavirus-related squamous lesions of the lower genital tract: low-grade and high-grade squamous intraepithelial lesion (LSIL and HSIL). Biomarker p16(INK4a) immunohistochemistry (IHC) was also recommended to assist classification: block-like positive staining supports the diagnosis of HSIL. We aim to assess the impact of LAST recommendations on our practice as well as to identify challenges and errors in p16 IHC implementation. We studied 262 cervical biopsies meeting 3 criteria: (1) HSIL diagnosis; (2) p16 IHC performed at time of diagnosis; and (3) patient's follow-up more than 12 months, including cervical cytology, biopsy, and excision. Among these patients, subsequent loop electrosurgical excision procedure and surveillance revealed 163 HSILs (62%), 28 LSILs (11%), and 71 "nondysplastic changes" (27%). We reviewed the latter 2 groups' original hematoxylin and eosin and p16 IHC slides. The diagnosis of HSIL was confirmed in 49 cases (49%), whereas 50 (51%) were reclassified as LSIL (n=46) or negative for dysplasia (n=4). These cases were initially overdiagnosed as HSIL because pathologists (1) overused p16 IHC on unequivocal LSIL (n=27) or (2) upgraded questionable lesions to HSIL based on nonblock p16 staining patterns (patchy or focal, n=23). To implement LAST recommendations successfully, we advocate judicious use of p16 in the designated circumstances and careful interpretation of staining patterns in the context of morphology. A standardized threshold for p16 positivity and supplementary guidance will help clarify the biomarker's utility and will facilitate LAST implementation in routine practice.

Prognostic value of p16 expression in Epstein-Barr virus-positive nasopharyngeal carcinomas

BACKGROUND

Overexpression of p16 is associated with improved outcomes among patients with oropharyngeal carcinoma. However, its role in the outcomes of patients with nasopharyngeal cancer (NPC) remains unclear.

METHODS

Eighty-six patients with NPC treated at MD Anderson Cancer Center from 2000 to 2014 were identified. Epstein-Barr virus (EBV) and human papillomavirus (HPV) status were determined by in situ hybridization (ISH) and p16 by immunohistochemical staining.

RESULTS

EBV positivity was associated with extended overall survival (OS; median, 95.0 vs 44.9 months; p < .004), progression-free survival (PFS; median, 80.4 vs 28.1 months; p < .013), and locoregional control (median, 104.4 vs 65.5 months; p < .043). In patients with EBV-positive tumors, p16 overexpression correlated with improved PFS (median, 106.3 vs 27.1 months; p < .02) and locoregional control (median, 93.6 vs 64.5 months; p < .02).

CONCLUSION

P16 overexpression is associated with improved PFS and locoregional control in patients with EBV-positive NPC. P16 expression may complement EBV status in predicting treatment outcomes for patients with NPC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1459-E1466, 2016.

Sensitivity of APTIMA HPV E6/E7 mRNA test in comparison with hybrid capture 2 HPV DNA test for detection of high risk oncogenic human papillomavirus in 396 biopsy confirmed cervical cancers

The sensitivity of E6/E7 mRNA-based Aptima HPV test (AHPV; Hologic, Inc.) for detection of cervical cancer has been reported based on only a small number of cases. We determined the sensitivity of AHPV in comparison with the DNA-based Hybrid Capture 2 HPV test (HC2; Qiagen) for the detection of oncogenic HPV in a large number of cervical cancers at the time of diagnosis using cervical samples obtained in ThinPrep (Hologic). Samples yielding discordant results were genotyped using Linear Array assay (LA; Roche). Of 396 cases tested, AHPV detected 377 (sensitivity, 95.2%; 95%CI: 93.1-97.3), and HC2 376 (sensitivity, 94.9%; 95%CI: 92.7-97.1) with an agreement of 97.2% (kappa 0.7; 95%CI: 0.54-0.87). Among six AHPV+/HC2- cases, LA identified oncogenic HPV types in four including a type 73 and was negative in two. Among five AHPV-/HC2+ cases, LA detected oncogenic HPV types in two including a type 73 and was negative in three. Of 14 AHPV-/HC2- cases, 13 were genotyped. LA detected oncogenic HPV types in six, non-oncogenic types in three, and was negative in four. This is the largest study to demonstrate the sensitivity of AHPV for the detection of invasive cervical cancer and this assay showed equal sensitivity to HC2.

Human papillomavirus 16 (HPV16) enhances tumor growth and cancer stemness of HPV-negative oral/oropharyngeal squamous cell carcinoma cells via miR-181 regulation

High-risk human papillomaviruses (e.g., HPV16, HPV18) are closely associated with the development of head and neck cancers including oral/oropharyngeal squamous cell carcinoma (OSCC). We previously demonstrated immortalization of normal human oral keratinocytes by introducing high-risk HPV whole genome, suggesting that HPV infection plays an important role in the early stage of oral carcinogenesis. Although HPV infection may occur in different stages of cancer development, roles of HPV in exacerbating malignant phenotypes in already-transformed cells in the context of cancer stemness are not clearly defined. In this study, we investigated the role of HPV16 in promoting the virulence of HPV-negative OSCC. Introducing HPV16 whole genome in HPV-negative OSCC increased malignant growth and self-renewal capacity, a key characteristic of cancer stem cells (CSCs). HPV16 also enhanced other CSC properties, including aldehyde dehydrogenase 1 (ALDH1) activity, migration/invasion, and CSC-related factor expression. Mechanistically, we found that HPV16 inhibited the expression of miR-181a and miR-181d (miR-181a/d) at the transcriptional level. Ectopic expression of miR-181a/d decreased anchorage independent growth and CSC phenotype of HPV16-transfected OSCC. Furthermore, silencing of miR-181a/d target genes, i.e., K-ras and ALDH1, abrogated the effects of HPV16 in HPV16-transfected OSCC, supporting the functional importance of HPV16/miR-181a/d axis in HPV-mediated oral carcinogenesis. Our study suggests that high-risk HPV infection further promotes malignancy in HPV-negative OSCC by enhancing cancer stemness via miR-181a/d regulation. Consequently, miR-181a/d may represent a novel therapeutic agent for the treatment of HPV-positive OSCC.

Combination of p16(INK4a) /Ki67 immunocytology and HPV polymerase chain reaction for the noninvasive analysis of HPV involvement in head and neck cancer

BACKGROUND

High-risk human papillomavirus (HPV) infection has been identified as a relevant risk for the development of head and neck squamous cell carcinomas (HNSCCs). As HPV status has also gained a role as a prognostic and predictive biomarker for this entity, there is a growing demand for valid HPV testing in HNSCC patients

METHODS

Liquid-based cytological smears from 45 HNSCC and 20 control patients were collected and used for simultaneous immunocytochemical p16(INK4a) /Ki67 staining using a CINtec PLUS kit after the presence of tumor cells was verified in a Papanicolaou-stained slide. The same cytological suspension was used for the detection of HPV DNA by specific polymerase chain reaction (PCR).

RESULTS

Tumor cells were detected in the swab material of 44 HNSCC patients corresponding to a sensitivity of 98% (44 of 45). PCR analysis revealed the presence of HPV DNA in the cytological suspension of 13 patients (13 of 65, 20%) with simultaneous p16(INK4a) /Ki67 expression by the tumor cells in 11 of these HPV DNA-positive samples (11 of 13, 85%) - a staining pattern that is strongly associated with a carcinogenic HPV infection.

CONCLUSIONS

A simultaneous immunocytochemical detection of p16(INK4a) and Ki67 can reliably be performed on liquid-based cytological smears from HNSCC patients using a CINtec PLUS kit. In addition, the same cytological material can be used for the detection of HPV DNA by specific PCR. The combined results of both techniques enable better discrimination between latent and carcinogenic HPV infections as well as HPV-negative cases and thus can provide information on the prognosis of HNSCC patients and facilitate therapeutic decisions.

Adjunct p16(INK4a) immunohistochemistry aids the detection of high-grade squamous intraepithelial lesions in endocervical curettage specimens

OBJECTIVES

We questioned whether the use of p16(INK4a) immunohistochemistry in endocervical curettage (ECC) specimens would improve the detection of high-grade squamous intraepithelial lesions (HSIL) in a high-risk patient population.

METHODS

Papanicolaou test results were retrieved in 58 consecutive ECC specimens that were previously diagnosed as no histopathologic abnormality in patients with antecedent HSIL or atypical squamous cells, cannot exclude HSIL. An H&E recut and immunohistochemistry for p16(INK4a) were performed on all cases.

RESULTS

HSIL were found in 18 (31%) ECC specimens originally interpreted as negative. Of these 18 cases, three had moderate-sized fragments of ectocervical epithelium with HSIL seen on the recut H&E with concurrent positivity for p16(INK4a). Fourteen cases had rare to occasional clusters of atypical cells with strong immunoreactivity for p16(INK4a). A single case showed a medium-sized fragment of HSIL on the p16(INK4a)-stained section.

CONCLUSIONS

The use of recuts and adjunct p16(INK4a) should be considered when evaluating ECC specimens in high-risk patient populations.

Ancillary Diagnostics in Gynecologic Cytology

Cytology has been the mainstay of cervical dysplasia and cancer screening in the United States. The specificity of a woman harboring a high-grade lesion when identified as high-grade squamous intraepithelial lesion on Pap test is high; however, the test suffers from low sensitivity. Epidemiology studies have demonstrated that human papillomavirus (HPV) types 16 and 18 account for most cervical squamous cell carcinomas. Tests have been developed to identify high-risk HPV, some specifically to identify HPV 16 and 18. Simultaneous to the increase in HPV detection methods, interdisciplinary groups are making recommendations on the managerial use of the tests.

Detection of HPV E7 oncoviral protein in cervical lesions by a new antibody

The availability of a new E7 mAb-based immunohistochemistry (IHC) detection assay, Cervimax, allowed for the first time reliable testing of the E7 protein marker in formalin-fixed and paraffin-embedded tissues from cervical lesions. E7-specific IHC staining patterns were compared with those patterns of cervical cancer biomarkers, including the viral capsid protein L1 and the surrogate biomarkers p16INK4A, p53, hTERT, ubiquitin, and Ki67. The use of a tissue microarray of 138 cervical tissue cores from different pathologic stages allowed for a first profiling of the various markers in comparison with E7. Cervimax staining patterns closely overlap with those from p16INK4A and human telomerase reverse transcriptase (hTERT) in IHC staining for high-grade cervical intraepithelial neoplasia and squamous cell carcinoma. In squamous cell carcinoma, E7 immunostaining matched better to hTERT and ubiquitin profiles. On the contrary, the pattern of E7 and L1 were different in all the squamous lesions. The nuclear staining of E7 significantly discriminates between low-grade cervical intraepithelial neoplasia and high-grade cervical intraepithelial neoplasia in the basal, parabasal, and superficial layers. The results obtained in the presented pilot study suggest E7 as a valid candidate biomarker for all the stages of the malignant progression of cervical cancer; however, more extensive studies are needed to confirm the causal effect of the oncoprotein E7 in the diagnosis of human papillomavirus-induced diseases. These results also suggest that the diagnostic interpretation of cervical lesions could be increased by the combination of E7 and L1 staining in the evaluation of risk of progression, because related to different phases of viral integration.

P16INK4A as a surrogate biomarker for human papillomavirus-associated oropharyngeal carcinoma: consideration of some aspects

Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinomas (OPSCCs) frequently show different clinical and pathological features, which tend to be younger age, better performance status, less tobacco and alcohol consumption, more poorly differentiated histopathology, but usually with better treatment response and prognosis compared with HPV-negative OPSCCs. In tumor tissue, HPV infection is closely correlated with p16(INK4A) expression, which has been suggested to be a surrogate biomarker of HPV infection. However, there is diversity of sensitivity and specificity about p16(INK4A) in surrogate detection of HPV status. Herein, we summarize the current knowledge and note some aspects for consideration concerning p16(INK4A) as a surrogate biomarker for HPV-associated OPSCC.

Ocular expression and distribution of products of the POAG-associated chromosome 9p21 gene region

It has recently been shown that there are highly significant associations for common single nucleotide polymorphisms (SNPs) near the CDKN2B-AS1 gene region at the 9p21 locus with primary open angle glaucoma (POAG), a leading cause of irreversible blindness. This gene region houses the CDKN2B/p15^INK4B_,CDKN2A/p16^INK4A and p14ARF (rat equivalent, p19^ARF) tumour suppressor genes and is adjacent to the S-methyl-5′-thioadenosine phosphorylase (MTAP) gene. In order to understand the ocular function of these genes and, therefore, how they may be involved in the pathogenesis of POAG, we studied the distribution patterns of each of their products within human and rat ocular tissues. MTAP mRNA was detected in the rat retina and optic nerve and its protein product was localised to the corneal epithelium, trabecular meshwork and retinal glial cells in both human and rat eyes. There was a very low level of p16^INK4A mRNA present within the rat retina and slightly more in the optic nerve, although no protein product could be detected in either rat or human eyes with any of the antibodies tested. P19^ARF mRNA was likewise only present at very low levels in rat retina and slightly higher levels in the optic nerve. However, no unambiguous evidence was found to indicate expression of specific P19^ARF/p14^ARF proteins in either rat or human eyes, respectively. In contrast, p15^INK4B mRNA was detected in much higher amounts in both retina and optic nerve compared with the other genes under analysis. Moreover, p15^INK4B protein was clearly localised to the retinal inner nuclear and ganglion cell layers and the corneal epithelium and trabecular meshwork in rat and human eyes. The presented data provide the basis for future studies that can explore the roles that these gene products may play in the pathogenesis of glaucoma and other models of optic nerve damage.

Transcriptionally active human papillomavirus is strongly associated with Barrett's dysplasia and esophageal adenocarcinoma

OBJECTIVES

The role of human papillomavirus (HPV) in Barrett's esophagus (BE) remains unclear. The few studies that have previously investigated HPV and esophageal adenocarcinoma (EAC) or BE have produced either negative data or positive results of doubtful clinical/etiological significance or have detected only low-risk HPV types. We therefore prospectively determined the prevalence of biologically active HPV in esophageal epithelium of patients representing the Barrett's metaplasia-dysplasia-adenocarcinoma sequence.

METHODS

HPV DNA was estimated by nested PCR and viral transcriptional activity detected by E6/7 oncogene mRNA expression and p16INK4A immunohistochemistry in fresh frozen and paraffin-embedded esophageal biopsies of patients with BE, Barrett's dysplasia (BD), and EAC, as well as controls. Biopsies were obtained from the transformation zone (squamocolumnar junction (SCJ)) and the lesion, or corresponding site in controls, i.e., 2 cm above the gastroesophageal junction (GEJ).

RESULTS

Of the 261 patients, 81 were positive for HPV DNA. In controls and BE, the virus was mostly detected at the transformation zone. Compared with controls (18.0%), HPV positivity was significantly more common in BD (68.6%, incidence rate ratio (IRR) 2.94, 95% confidence interval (CI) 1.78-4.85, P<0.001) and EAC (66.7%, IRR 2.87, 95% CI 1.69-4.86, P<0.001), but not in BE (22.1%, IRR 1.06, 95% CI 0.60-1.85, P=0.85). Of the patients, 92.6% were high-risk (HR) HPV, i.e., types 16 and 18. Again, p16INK4A positivity was greatest in BD and EAC and much less in BE patients (44.1%, IRR 17.0 (95% CI 4.86-59.6, P<0.001), 44.4%, 17.0 (95% CI 4.87-59.4, P<0.001), and 10.6%, 3.93 (95% CI 1.01-15.3, P=0.048) respectively). In 66 HPV DNA-positive patients tested for E6/E7 mRNA, none of the control (n=16) or BE (n=13) individuals were positive, whereas 9/22 BD and 9/15 EAC patients demonstrated oncogene expression (P<0.001). When HPV DNA, p16INK4A, and E6/E7 mRNA were all positive, there was a very strong association with disease severity (SCJ: odds ratio (OR) 104, 95% CI 20.3-529, P<0.001; lesion: OR 62.2, 95% CI 12.4-311, P<0.001) than when all were negative.

CONCLUSIONS

Transcriptionally active HR-HPV was strongly associated with BD and EAC, but was largely biologically irrelevant in BE and controls, suggesting a potential role in esophageal carcinogenesis. These data provide robust justification for further detailed longitudinal, interventional, and molecular studies.

Cutaneous manifestations of dabrafenib (GSK2118436): a selective inhibitor of mutant BRAF in patients with metastatic melanoma

BACKGROUND

Inhibitors of mutant BRAF are emerging as standard of care in patients with metastatic melanoma carrying relevant oncogenic mutations. Cutaneous reactions are frequent and significant. We conducted a systematic prospective dermatological review of all patients enrolled at a single institution in the phase I/II clinical trial of the mutant BRAF inhibitor dabrafenib (GSK2118436).

OBJECTIVES

To identify the cutaneous manifestations of the BRAF inhibitor dabrafenib; to form diagnostic criteria to standardize the diagnosis of verrucal keratotic squamoproliferative lesions; and to bring awareness to the medical community of the importance of dermatological assessment of patients taking dabrafenib.

METHODS

Patients enrolled in the phase I/II trial (n = 43) were monitored for the development of new skin lesions. Each new lesion was photographed, a clinical diagnosis recorded and, where appropriate, a biopsy taken. Human papillomavirus (HPV) and p16 immunohistochemistry analyses were performed.

RESULTS

The most frequently observed lesions were verrucal keratotic squamoproliferative lesions (49%), Grover's disease (27%) and reactive hyperkeratotic lesions on the soles, at points of friction (22%). Eighteen squamous cell carcinomas (SCCs) occurred in 20% of patients. Most SCCs appeared between weeks 6 and 24 following commencement of therapy on both sun-damaged and nonsun-damaged skin. All SCCs were well differentiated, five were of the keratoacanthoma type, and two were SCC in situ. Other lesions observed included seborrhoeic keratoses, epidermal cysts, acneiform eruptions, hair loss and changes in hair structure. HPV was negative in 15 of the 16 tissues studied and p16 expression was higher in SCCs compared with verrucal keratoses.

CONCLUSIONS

Administration of the mutant BRAF inhibitor dabrafenib is associated with induction of keratinocytic proliferation, which in some cases develops features of low-grade malignancy. Highly oncogenic HPV infection is unlikely to be a contributor to the formation of SCCs or verrucal keratoses.

Dynamin 2 expression as a biomarker in grading of cervical intraepithelial neoplasia

OBJECTIVE

Dynamin 2, which plays a role in endocytosis, is known to be required for HPV infection on host cells. We investigated dynamin 2 as a biomarker in grading of cervical intraepithelial neoplasia (CIN) by comparing with Ki-67 expression and the type of HPV infection (low-risk vs. high-risk).

STUDY DESIGN

We performed immunohistochemical stains of dynamin 2 and Ki-67 on tumor samples of patients with CIN and the type of HPV infection was investigated.

RESULTS

All the patients with reactive changes (n=7) or normal (n=4) did not show dynamin 2 expression. There were 33, 14, and 12 cases with CIN I, II, and III, respectively, and there was a negative correlation between the degree of dynamin 2 expression and the severity of CIN lesions with statistical significance (P<0.001). Negative expression of dynamin 2 was more sensitive for the detection of CIN II/III than high expression (2+) of Ki-67 (96.2% vs. 73.1%, P=0.041). Among patients in whom HPV infection was detected, the degrees of dynamin 2 expression were not associated with the type of HPV infection (low-risk vs. high-risk). Overall, there was a negative correlation between the expression patterns of Ki-67 and dynamin 2.

CONCLUSION

We found that dynamin 2 may be a helpful biomarker in grading of CIN lesions and a candidate biomarker for detecting low grade CIN with high sensitivity.

The Utility of p16INK4a and Ki-67 as a Conjunctive Tool in Uterine Cervical Lesions

Background

Immunohistochemical staining for p16INK4a and Ki-67 has been used to improve the accuracy in making a diagnosis of the uterine cervix cancer on biopsy. This study was conducted to examine the usefulness of these markers in the pathological diagnosis based on cervical biopsy.

Methods

We selected a consecutive series of 111 colposcopically directed cervical punch biopsies. Using these biopsy samples, we performed an immunohistochemical staining for p16INK4a and Ki-67 to establish a diagnosis. The slides were circulated among four pathologists in a sequential order: the hematoxylin and eosin (H&E) slide, H&E slide and p16INK4a-stained slide, and H&E slide, p16INK4a- and Ki-67-stained slides.

Results

The overall rates of the concordance in the first, the second, and the third diagnoses were 77.5%, 82.0%, and 82.0%, respectively. The rate of the concordance in the diagnosis of cervical intraepithelial neoplasm (CIN) 2/3 was increased from 62.2% to 73.0%. But there was a variability in the rate of the revision of the diagnosis between the pathologists. With the application of criteria for interpreting the expressions of p16INK4a and Ki-67, benign and CIN 1 lesions showed a p16INK4a expression score of 0 or 1. But CIN 2 and CIN 3 lesions showed a p16INK4a expression score of 2 and 3, respectively.

Conclusions

The immunostain for p16INK4a and Ki-67 might be useful in reducing an inter-observer variability. But criteria for interpreting both markers should be strictly applied.

A comparison of clinically utilized human papillomavirus detection methods in head and neck cancer

Detection of human papillomavirus (HPV) in head and neck cancer has therapeutic implications. In situ hybridization and immunohistochemistry for p16 are used by surgical pathologists. We compared the sensitivity and specificity of three popular commercial tests for HPV detection in head and neck squamous cell carcinomas with a 'gold standard' HPV PCR assay. A total of 110 prospectively collected, formalin-fixed tumor specimens were compiled onto tissue microarrays and tested for HPV DNA by in situ hybridization with two probe sets, a biotinylated probe for high-risk (HR) HPV types 16/18 (Dako, CA, USA) and a probe cocktail for 16/18, plus 10 additional HR types (Ventana, AZ, USA). The p16(INK4) expression was also assessed using a Pharmingen immunohistochemistry antibody (BD Biosciences, CA, USA). Tissue microarrays were stained and scored at expert laboratories. HPV DNA was detected by MY09/11-PCR, using Gold AmpliTaq and dot-blot hybridization on matched-fresh frozen specimens in a research laboratory. HPV 16 E6 and E7-RNA expression was also measured using RT-PCR. Test performance was assessed by a receiver operating characteristic analysis. HR-HPV DNA types 16, 18 and 35 were detected by MY-PCR in 28% of tumors, with the majority (97%) testing positive for type 16. Compared with MY-PCR, the sensitivity and specificity for HR-HPV DNA detection with Dako in situ hybridization was 21% (95% confidence interval (CI): 7-42) and 100% (95% CI: 93-100), respectively. Corresponding test results by Ventana in situ hybridization were 59% (95% CI: 39-78) and 58% (95% CI: 45-71), respectively. The p16 immunohistochemistry performed better overall than Dako (P=0.042) and Ventana (P=0.055), with a sensitivity of 52% (95% CI: 32-71) and specificity of 93% (95% CI: 84-98). Compared with a gold standard HPV-PCR assay, HPV detection by in situ hybridization was less accurate for head and neck squamous cell carcinoma on tissue microarrays than p16 immunohistochemistry. Further testing is warranted before these assays should be recommended for clinical HPV detection.

Performance of p16INK4a immunocytochemistry as a marker of anal squamous intraepithelial lesions

BACKGROUND

Protein p16(INK4a) immunocytochemistry (ICCp16) has the potential to reveal lesions at risk of progression to anal cancer. This study examined measures of diagnostic validity of ICCp16 in HIV-positive patients treated at the Tropical Medicine Foundation of Amazonas in the coloproctology outpatient clinic.

METHODS

One hundred ninety HIV-positive patients were consecutively enrolled in 2007 and 2008. All patients underwent anal cytologic sampling to perform ICCp16 in conventional and GluCyte (Synermed International, Westfield, Indiana and S¸ao Paulo, Brazil) smears and also for genotyping of human papillomavirus (HPV). Patients were then subjected to anal biopsies monitored by high-resolution anoscopy. Hematoxylin-eosin and immunoperoxidase p16 (clone 6H12) stains were performed in slides with biopsied and cytological specimens, respectively. HPV genotyping on anal scrapings was performed by a polymerase-chain reaction (PCR)-based method. The immunochemical findings were compared with histopathological and PCR results in contingency tables and analyzed by nonparametric tests. Measures of diagnostic validity of ICCp16 were calculated. Statistical significance was set at P ≤ .5.

RESULTS

There was no statistically significant association between the immunochemical results (conventional or GluCyte smears) and histopathological or HPV genotyping findings (P > .05). In the best scenario, ICCp16 presented 31% sensitivity and 81% specificity for the diagnosis of anal squamous intraepithelial lesion (ASIL) and 30% and 66%, respectively, for the diagnosis of infection with high-risk HPV.

CONCLUSIONS

There was no association between ICCp16 results and histopathological findings nor between ICCp16 and HPV genotyping. ICCp16 showed poor sensitivity and moderate specificity for the diagnosis of ASIL or high-risk HPV.

p16(Ink4a) overexpression in cancer: a tumor suppressor gene associated with senescence and high-grade tumors

p16(Ink4a) is a protein involved in regulation of the cell cycle. Currently, p16(Ink4a) is considered a tumor suppressor protein because of its physiological role and downregulated expression in a large number of tumors. Intriguingly, overexpression of p16(Ink4a) has also been described in several tumors. This review attempts to elucidate when and why p16(Ink4a) overexpression occurs, and to suggest possible implications of p16(Ink4a) in the diagnosis, prognosis and treatment of cancer.

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.

Diagnostic value and implications of vimentin expression in normal, reactive and neoplastic endocervical epithelium

AIMS

To assess vimentin immunoreactivity in normal, reactive and neoplastic endocervical epithelium, and compare the results with p16 protein, Ki-67 and bcl-2 expression.

METHODS

Sixty-two cervical biopsy specimens including normal endocervical epithelium, tubo-endometrioid metaplasia, adenocarcinoma in situ, stratified mucin producing intraepithelial lesions (SMILE), and invasive adenocarcinomas were stained immunohistochemically for vimentin and for p16 protein, Ki-67 and bcl-2. Twelve cases also included areas of high grade cervical intraepithelial neoplasia (CIN).

RESULTS

Normal endocervical epithelium usually showed subtle but distinct sub-nuclear and delicate lateral cell border vimentin expression while tubo-endometrioid metaplasia exhibited more diffuse cytoplasmic immunoreactivity. Usually adenocarcinoma in situ was completely negative and therefore vimentin staining sharply distinguished the benign and neoplastic epithelial elements. The SMILE lesions and high grade CIN were also vimentin negative in most cases. Most invasive adenocarcinomas were not stained but focal vimentin immunoreactivity was observed in 7/18 cases, and was restricted to small glands and infiltrating cell clusters at the deep (advancing) tumour margin.

CONCLUSIONS

Normal endocervical cells often exhibit vimentin staining, and this is increased in reactive and metaplastic situations, whereas adenocarcinoma in situ is usually completely negative. Therefore vimentin is a useful additional diagnostic marker in the assessment of problematic cervical glandular lesions. The localised re-expression of vimentin at the deep margin of some endocervical adenocarcinomas may be relevant to the process of tumour progression and invasion in these cases.

Cyclin D1 immunoreactivity in normal endocervix and diagnostic value in reactive and neoplastic endocervical lesions

It may be difficult to distinguish reactive glandular lesions from adenocarcinoma in situ of the uterine cervix, and although several immunohistochemical markers have established value in this diagnostic setting, none is completely reliable. We have noted that neoplastic endocervical lesions often show loss of nuclear cyclin D1 expression in contrast to benign glandular cells. Therefore, we investigated cyclin D1 staining in a series of 64 cervical biopsy specimens including examples of normal and reactive endocervical epithelium, adenocarcinoma in situ, stratified mucin-producing intraepithelial lesions, and invasive adenocarcinoma. Thirteen specimens also included a component of high-grade cervical squamous intraepithelial neoplasia. Normal endocervical epithelium usually expressed cyclin D1, although staining was typically focal, and there was increased immunoreactivity in reactive and metaplastic glandular cells including tubo-endometrioid metaplasia. In contrast, most cases of adenocarcinoma in situ were completely negative and, therefore, cyclin D1 staining distinguished benign from neoplastic epithelial cells. Although focal cyclin D1 expression was observed in 5/19 cases of adenocarcinoma in situ, the staining was associated with more marked cytological atypia precluding confusion with a reactive process. The invasive adenocarcinomas were mainly negative for cyclin D1. However, focal staining was observed in 10/19 cases and was mainly restricted to cells at the deep tumor margin, or to small infiltrative glands and detached cell clusters within the stroma. In conclusion, cyclin D1 can be included within an immunohistochemical panel to aid in the distinction between reactive cervical glandular lesions and adenocarcinoma in situ. The localized distribution of staining within invasive lesions suggests that cyclin D1 up-regulation has a specific role during the progression of some endocervical adenocarcinomas.

Conjunctive p16INK4a testing significantly increases accuracy in diagnosing high-grade cervical intraepithelial neoplasia

The histopathologic interpretation of cervical intraepithelial neoplasia (CIN) is subject to a high level of interobserver variability and a substantial number of false-positive and false-negative results. We assessed the impact of the conjunctive interpretation of p16(INK4a)-immunostained slides on the accuracy of community-based pathologists in diagnosing high-grade cervical intraepithelial neoplasia (CIN; CIN 2 and CIN 3) in biopsy specimens. Twelve pathologists rendered independent diagnoses on a set of 500 H&E-stained cervical punch and conization specimens. Results were compared with a dichotomized "gold standard" established by consensus of 3 gynecopathology experts. When p16(INK4a)-immunostained slides were added and conjunctively interpreted with the H&E-stained slides, a significant increase in diagnostic accuracy for the detection of high-grade CIN was observed (P = .0004). Sensitivity for high-grade CIN was increased by 13%, cutting the rate of false-negative results in half. Agreement of community-based pathologists in diagnosing high-grade CIN was significantly improved (mean kappa values advanced from 0.566 to 0.749; P < .0001). Reproducibility of p16(INK4a) stain interpretation was excellent (kappa = 0.899). Our results show that conjunctive interpretation of p16(INK4a)-stained slides could significantly improve the routine interpretation of cervical histopathology.

Fluorescence in situ hybridization markers for prediction of cervical lymph node metastases

The presence of lymph node metastases is associated with poor prognosis in early stage cervical cancer. As of yet, no molecular markers predicting lymph node metastases have been identified. We examined single genetic markers and a composite marker, comprised of three fluorescence in situ hybridization (FISH) probes targeting the genes LAMP3, PROX1, and PRKAA1, in pretreatment cervical biopsies from 16 lymph node positive cases and 15 lymph node negative controls from women with stage IB and IIA cervical cancer. In addition, we determined clonal patterns by including CCND1 to compare the clonal constitution of primary tumors and associated lymph node metastases. The composite FISH marker allowed for classification of patients into those with and without lymph node metastases with a sensitivity and specificity of 75% and 87%, respectively (P = 0.001). The positive predictive value and negative predictive value were 86% and 76%, respectively. Clonal patterns varied among the tumors. In many cases, changes between the primary tumor and lymph node metastases in the most common clones may indicate that certain clones have a growth advantage for establishing metastases in lymph nodes. We conclude that the composite FISH marker may be useful for determining risk for subsequent development of lymph node metastases in patients with cervical cancer.