Immunohistochemical expression of p16(INK4a) is predictive of HR-HPV infection in cervical low-grade lesions.

The p16(INK4a) is a cyclin-dependent kinase inhibitor that decelerates the cell cycle by inactivating the cyclin-dependent kinases involved in the phosphorylation of the retinoblastoma protein (RB). Expression of E6 and E7 oncogenes of high-risk (HR) human papillomavirus (HPV), affecting the RB-p16 pathway, leads to p16 upregulation. Although it is widely reported that p16 is overexpressed in a high percentage of preneoplastic lesions and in almost all carcinomas of the uterine cervix, protein upregulation and its correlation with HPV infection in low-grade lesions is still being debated. In this study, we investigated in parallel, p16 expression and HPV infection in 100 cervical biopsies (17 normal tissues, 54 CIN1, 10 CIN2, 11 CIN3, eight invasive squamous cancers). Results obtained demonstrated that none of the 17 normal cervical tissues, evaluated by immunohistochemistry, presented p16 positivity whereas, starting from CIN1 (31%) to CIN2 (90%), CIN3 (100%) and carcinomas (100%), a constant and significant increase of protein overexpression (P<0.0001) was observed. In addition, p16 overexpression consistently showed elevated sensitivity (84%) and specificity (98%) in detecting HR-HPV infection with a high positive predictive value (97%) and negative predictive value (86%). Of interest, 93% of the p16-positive CIN1 were also HR-HPV infected. Our findings confirmed that p16 overexpression is associated to high-grade precancerous lesions and cervical carcinomas, and further demonstrated that immunohistochemical evaluation of p16 may be a useful biomarker in identifying HR-HPV-infected low-grade lesions.     

Detection of human papilloma virus and p16 expression in high-grade adenoid cystic carcinoma of the head and neck

Squamous cell carcinoma of the head and neck, particularly basaloid squamous cell carcinoma, may be difficult to distinguish from high-grade adenoid cystic carcinoma. Evidence of human papilloma virus (HPV) infection, particularly HPV 16, is frequently found in non-keratinizing oropharyngeal squamous cell carcinoma. Immunoreactivity for p16, a surrogate marker for HPV infection, often parallels the HPV infection status in oropharyngeal squamous cell carcinoma. However, the incidence and correlation between p16 expression and HPV infection in high-grade adenoid cystic carcinoma is unknown. Sixteen cases of high-grade adenoid cystic carcinoma, three cases of dedifferentiated adenoid cystic carcinoma and eight cases of low-/intermediate-grade adenoid cystic carcinoma were identified for inclusion in the study. All cases were tested by immunohistochemistry for p16 expression and in situ hybridization for high- and low-risk HPV. Eight cases (100%) of low-to-intermediate-grade adenoid cystic carcinoma were focally positive for p16, all of which were negative for HPV. In all, 14 of 16 cases (88%) of high-grade adenoid cystic carcinoma and three cases (100%) of dedifferentiated adenoid cystic carcinoma were positive for p16; strong and diffuse staining was noted in three cases (3 of 19, 16%). Two cases (11%) of high-grade adenoid cystic carcinoma, which were also diffusely positive for p16, showed the presence of high-risk HPV. These findings suggest that the presence of HPV infection in high-grade adenoid cystic carcinoma is infrequent, even in the presence of p16 immunostaining. Nevertheless, HPV positivity should not be used to exclude the possibility of high-grade adenoid cystic carcinoma when the differential diagnosis includes squamous cell carcinoma. Moreover, although p16 overexpression is often used as a surrogate marker for HPV in squamous cell carcinoma, it cannot be used in this manner in high-grade adenoid cystic carcinoma.     

Human papillomavirus genotyping by oligonucleotide microarray and p16 expression in uterine cervical intraepithelial neoplasm and in invasive carcinoma in Korean women

For evaluating the diagnostic significance of p16(INK4A) over-expression in the uterine cervical intraepithelial neoplasm and in invasive carcinoma, human papillomavirus (HPV) was detected and genotyped by oligonucleotide microarray in archival tissues of 117 cervical specimens, including 47 invasive squamous cell carcinomas (SCC), 30 cases of cervical intraepithelial neoplasia (CIN), 20 adenocarcinomas, and 20 cases of non-neoplastic cervix. The expression of p16(INK4A) protein was immunohistochemically studied in these cases and in five HPV-positive and one HPV-negative cervical cancer cell lines. HPV was detected in 50% of CIN, 61.7% of SCC, and 45.5% of adenocarcinomas. p16(INK4A) expression was seen in all 20 cases of adenocarcinoma, 78.7% (37/47) of SCC, and 96.7% (29/30) of CIN, but not in any cases of the non-neoplastic cervix. There was no difference in p16(INK4A) expression between the HPV-positive and HPV-negative cervical lesions. All HPV-positive and -negative cervical cancer cell lines expressed p16(INK4A) protein. In conclusion, the presence of p16(INK4A) expression in cervical squamous and glandular epithelium indicates the existence of dysplasia or malignancy in the uterine cervix, regardless of HPV infection.     

Clinicopathological Implications of Human Papilloma Virus (HPV) L1 Capsid Protein Immunoreactivity in HPV16-Positive Cervical Cytology

Background: The objective of this study was to investigate the expression of human papilloma virus (HPV) L1 capsid protein in abnormal cervical cytology with HPV16 infection and analyze its association with cervical histopathology in Korean women.Material and Methods: We performed immunocytochemistry for HPV L1 in 475 abnormal cervical cytology samples from patients with HPV16 infections using the Cytoactiv^® HPV L1 screening set. We investigated the expression of HPV L1 in cervical cytology samples and compared it with the results of histopathological examination of surgical specimens.Results: Of a total of 475 cases, 188 (39.6%) were immunocytochemically positive and 287 (60.4%) negative for HPV L1. The immunocytochemical expression rates of HPV L1 in atypical squamous cells of unknown significance (ASCUS), low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), and cancer were 21.8%, 59.7%, 19.1%, and 0.0%, respectively. LSIL exhibited the highest rate of HPV L1 positivity. Of a total of 475 cases, the multiple-type HPV infection rate, including HPV16, in HPV L1-negative cytology samples was 27.5%, which was significantly higher than that in HPV L1-positive cytology samples (p = 0.037). The absence of HPV L1 expression in ASCUS and LSIL was significantly associated with high-grade (≥cervical intraepithelial neoplasia [CIN] 2) than low-grade (≤CIN1) histopathology diagnoses (p < 0.05), but was not significantly different between HPV16 single and multiple-type HPV infections (p > 0.05). On the other hand, among 188 HPV L1-positive cases, 30.6% of multiple-type HPV infections showed high-grade histopathology diagnoses (≥CIN3), significantly higher than the percentage of HPV16 single infections (8.6%) (p = 0.0004)Conclusions: Our study demonstrates that the expression of HPV L1 is low in advanced dysplasia. Furthermore, the absence of HPV L1 in HPV16-positive low-grade cytology (i.e., ASCUS and LSIL) is strongly associated with high-grade histopathology diagnoses. The multiplicity of HPV infections may have an important role in high-grade histopathology diagnoses (≥CIN3) in HPV L1-positive cases.     

Kategorisierung der Tumoren der Cervix uteri

In the 2014 WHO classification, squamous cell precursor lesions are classified as low-grade and high-grade intraepithelial lesions. LSIL corresponds to CIN1, HSIL includes CIN2 and CIN3. Only adenocarcinoma in situ (AIS) is accepted as precursor of adenocarcinoma and includes the stratified mucin-producing intraepithelial lesion (SMILE). Although relatively rare, adenocarcinoma and squamous cell carcinoma can be mixed with a poorly differentiated neuroendocrine carcinoma. Most cervical adenocarcinomas are low grade and of endocervical type. Mucinous carcinomas show marked intra- and extracellular mucin production. Almost all squamous cell carcinomas, the vast majority of adenocarcinomas, and many rare carcinoma types are HPV related. For low grade endocervical adenocarcinomas, the pattern-based classification according to Silva should be reported. Neuroendocrine tumors are rare and are classified into low-grade and high-grade, whereby the term carcinoid is still used.     

Histologic and immunophenotypic classification of cervical carcinomas by expression of the p53 homologue p63: a study of 250 cases

Recent studies of the p53 homologue p63 indicate that this gene is preferentially expressed in basal and immature cervical squamous epithelium. This study correlated p63 expression with morphologic phenotype and human papillomavirus (HPV) type in a wide range of cervical neoplasms. Two hundred fifty cases of cervical carcinoma, including squamous cell carcinoma (SCCA; n = 178), adenocarcinoma (ADCA; n = 28), adenosquamous carcinoma (ASCA; n = 8), neuroendocrine carcinoma (NECA; n = 15), and other variant or mixed types (n = 21) were studied. Ninety-seven percent of SCCA, 0% of ADCA, and 0% of SCUC showed strong (>75% v <30%) positivity for p63 (P<.001). p63 sharply distinguished SCCA (p63+) from ADCA (p63-), Large-cell, poorly differentiated carcinomas were distinguished as putative glandular (glassy cell) or squamous (lymphoepithelial-like or spindle cell) types based on p63 staining. Eight (73%) of 11 neuroendocrine tumors tested were chromogranin positive; all showed no or low (<30%) levels of p63 immunostaining. Absence of p63 was also associated with a subset of nonneuroendocrine undifferentiated carcinomas. Transitions from squamous to columnar or undifferentiated morphology coincided with loss of p63 expression. A strong association between HPV 16 and p63 positivity was identified because of the colocalization of both within tumors of squamous phenotype. p63 is a powerful marker for squamous differentiation and, when diffusely expressed, excludes a glandular or neuroendocrine differentiation. p63 may be useful for differentiating pure squamous or glandular from adenosquamous carcinomas, tracking shifts in differentiation within tumors, supporting (by its absence) the diagnosis of neuroendocrine carcinomas, and clarifying the spectrum of poorly differentiated carcinomas lacking either squamous or neuroendocrine differentiation.     

人乳头状瘤病毒阴性的宫颈癌及其癌前病变中p16INK4A蛋白表达和DNA倍体分析

目的探讨人乳头状瘤病毒（HPV）感染阴性的宫颈癌及其癌前病变中p16^INK4A蛋白表达和DNA倍体分析的临床病理学意义。方法应用PCR方法筛查出HPV感染阴性的20例慢性宫颈炎、20例宫颈上皮内瘤变（CIN）、3例宫颈腺上皮内瘤变（CGIN）、38例浸润性鳞状细胞癌（鳞癌）和15例浸润性腺癌作为研究对象。应用免疫组织化学（LSAB）染色方法检测p16^INK4A蛋白在这些病变组织中的表达,并结合流式细胞仪DNA倍体分析探讨HPV阴性的宫颈癌的早期诊断和预后判定。结果p16^INK4A蛋白特异性地表达在CIN和CGIN病变、鳞癌以及腺癌细胞的胞核和胞质中,而在正常鳞状上皮和腺上皮中没有任何阳性表达信号。另外,DNA异倍体在浸润性鳞癌和腺癌中的表达率明显高于CIN病变组（P〈0．01）。在有淋巴结转移的浸润癌中DNA异倍体存在的百分率高于无淋巴结转移组,但尚未发现差异有统计学意义。在8例p16^INK4A表达阴性的浸润性鳞癌中有2例表现为DNA异倍体。结论p16^INK4A蛋白检测可以作为HPV感染阴性的宫颈鳞癌及腺癌的早期诊断指标,结合DNA倍体分析将对宫颈恶性肿瘤的诊断有重要的辅助意义。     

Immunohistochemical detection of p53 in cervical epithelial lesions with or without infection of human papillomavirus types 16 and 18

Using formalin-fixed and paraffin-embedded cervical tissues, we examined infection with human papillomavirus (HPV) types 16 and 18 by Southern blot analysis following polymerase chain reaction (PCR), and the accumulation of p53 protein by immunohistochemistry in 30 cases of normal or metaplastic cervix, 17 cases of cervical intraepithelial neoplasia grade I (CIN I), 20 cases of CIN II, 37 cases of CIN III and 23 cases of invasive squamous cell carcinoma (ISCC). In addition, we examined the ratio of HPV-infected cells by in situ hybridization (ISH) and the alteration of p53 gene using PCR followed by single-strand conformation polymorphism (PCR-SSCP) in 2 cases of CIN III and 12 cases of ISCC, in which overexpression of p53 was immunohistochemically detected. HPV DNA was detected in 5 cases (16.7%) of normal or metaplastic cervix, 5 cases (29.4%) of CIN I, 9 cases (45.0%) of CIN II, 26 cases (70.3%) of CIN III and 15 cases (65.2%) of ISCC. Positivity for HPV in the groups of CIN III and ISCC was significantly higher than in the normal or metaplastic cervix (P<0.05). The accumulation of p53 was not detected in the normal or metaplastic cervix, CIN I and CIN II. High-level p53 accumulation was identified in basal and suprabasal atypical cells in 27.0% (10/37) of CIN III and in carcinoma cells in 43.5% (10/23) of ISCC cases, and low-level accumulation was identified in atypical cells of 35.1% (13/37) of CIN III and in carcinoma cells in 30.4% (7/23) of ISCC cases. The accumulation of p53 was found to coexist with infection by HPV in 17 (46.0%) of 37 CIN III cases and 12 (52.2%) of 23 ISCC cases, and high-level p53 accumulation was more frequently detected in HPV-positive ISCC cases. Either HPV infection or accumulation of p53 was found in 16.7% (5/30) of the cases of normal or metaplastic cervix, 29.4% (5/17) of CIN I, 45.0% (9/20) of CIN II, 86.5% (32/37) of CIN III and 87.0% (20/23) of ISCC cases. These results suggest that the inactivation of p53 function by HPV infection or alteration of p53 protein itself precedes the development of tumours with a fully malignant and invasive phenotype and plays an important role in tumorigenesis in the uterine cervix. ISH study provided no correlation between the degree of immunohistochemical positivity for p53 and the ratio of HPV-positive cells in the same lesions. PCR-SSCP detected the alteration of p53 gene in at least 4 cases of ISCC, 2 of which were accompanied by HPV infection.     

The Detection of Human Papillomaviruses in Cervical Biopsies by Immunohistochemistry and In Situ Hybridization

The presence of human papillomavirus (HPV) types 6, 16 and 8 in cervical biopsies can be detected by an immunoperoxidase technique using type-restricted monoclonal antibodies raised against fusion proteins representing the L1 major capsid proteins of these three HPV types. In a retrospective study ( n = 54) we have used these antibodies and biotinylated DNA probes of HPV 6.16 and 18 lo detect and type HPV in formalin-fixed material from the cervix. The biopsies were classified histologically into normals, wart infections without dysplasia, cervical intraepithelial neoplasia (CIN)and squamous cell carcinomas. Antibody staining showed that 22% of all CIN was positive for HPV 16and 40% of cervical warts were positive for HPV 6, 16 and 18, There was no HPV capsid protein detected in the normals and squamous cell carcinomas using these antibodies, whereas 25% of the tumours were positive for HPV 16 by in situ hybridization. Sections of cervical warts and CIN positive for HPV types by in situ hybridization were also positive by antibody staining which suggests that both techniques are detecting replicating virus. We feel these two techniques complement each other in detection and typing of HPV in cervical biopsies from patients with active disease.     

Human papillomavirus infection, centrosome aberration, and genetic stability in cervical lesions.

DNA replication and centrosome duplication have to be strictly synchronized to guarantee genomic stability. p53, pRb, cyclin E, and cyclin A are reported to be involved in the synchronizing process. We investigated the relationship between papillomavirus infection, centrosome aberration and aneuploidy during genesis of cervical carcinoma. The number of centrosomes found in cells from normal cervical epithelium (n = 5), condyloma acuminata (n = 5), cervical intraepithelial neoplasia (CIN) I, II, and III (n = 14) and invasive cervical carcinoma (n = 5) was analyzed by gamma tubulin immunofluorescence staining. The nuclear DNA content was investigated by image cytometry and human papillomavirus (HPV) infection was determined by polymerase chain reaction. Normal epithelia and condyloma acuminata showed cells with one or two centrosomes, whereas CIN lesions showed cells with an increasing number of centrosomes. This abnormality was found to be lowest in CIN I lesions, increased with advancing grade of CIN and was highest in lesions of invasive carcinomas. In parallel, an increasing number of cells with aberrant DNA content was seen. All carcinomas and all except one of the CIN III lesions showed aneuploidy. Three CIN II cases were aneuploid and two cases with CIN I were tetraploid. Normal epithelia and condyloma acuminata showed diploidy. All invasive carcinomas and lesions with CIN were positive for high-risk HPV types 16, 18, or 31, except one invasive carcinoma and one CIN II lesion positive for universal primers only. Three condyloma acuminata were HPV 16-positive and one HPV 6-positive. The results suggest that high-risk HPV infection is correlated to a progressive numerical disturbance of centrosome replication followed by progressive chromosomal aberrations in CIN lesions and invasive carcinomas.     

Distribution of HPV genotypes in uterine cervical lesions in Yanbian, northern China

The aim of the present study was to investigate the distribution of HPV genotypes in uterine cervical lesions in Yanbian, northern China. HPV-DNA chip (oligonucleotide microarray) and cervical biopsy were used for 322 women in 1998-2005. All the normal cervical epithelia were negative for HPV. The positive rate of high-risk HPV was 33.9% in cervical intra-epithelial neoplasia (CIN)-1, 51.6% in CIN-2, 57.7% in CIN-3, 66.7% in cervical glandular intra-epithelial neoplasia (CGIN), 91.7% in squamous cell carcinoma (SCC), and 78.6% in adenocarcinoma. HPV-16 was the major type in all CIN and SCC cervical lesions, but in cervical adenocarcinoma HPV-18 was the most common type, and HPV-16 was the second most common type. Several cases of CIN-3, SCC and adenocarcinoma had multiple types of HPV, but there was none in CIN-1/2. In summary, HPV-16 is the type most frequently involved in the development of SCC of the cervix, and this may be helpful for the prediction of the development and progress of CIN-2/3, whereas both HPV-18 and -16 play a prominent role in the development of adenocarcinoma and CGIN of the cervix in Yanbian, northern China.     

Detection of human papillomavirus DNA sequences by in situ DNA-DNA hybridisation in cervical intraepithelial neoplasia and invasive carcinoma: a retrospective study.

Human papillomavirus (HPV) infection of cervical intraepithelial neoplasia (CIN) and invasive cervical carcinoma was investigated using in situ DNA-DNA hybridisation on histological sections of formalin fixed, paraffin embedded tissue to assess the technique's sensitivity and to assess retrospectively the association between HPV16 and invasive cervical carcinoma. HPV DNA was detected in 16 of 33 biopsy specimens of CIN. Cells containing viral DNA were more numerous than those positive for viral structural proteins. HPV DNA was also present in less differentiated cells deeper in the epithelium. The detection rate in CIN was lower than that reported for other hybridisation techniques such as Southern blotting. In a retrospective study of biopsy specimens of invasive squamous carcinoma of the cervix HPV16 DNA, the virus most commonly associated with cervical malignant disease, was found in 20 of 25 cases, including those dating from as far back as 1932. The level of sensitivity was similar to that reported for other hybridisation techniques. DNA positive cells were focally distributed in the invasive tumours, and most tumour cells were negative for viral DNA, a result consistent with the low copy number found in malignant cells. It is concluded that HPV16 is not a new virus but that its prevalence is a result of changes in sexual behaviour and that in situ hybridisation is useful in the localisation of HPV DNA replication in CIN and invasive carcinoma.     

子宫颈癌中Gli蛋白过表达的临床病理学意义

目的 研究Gli蛋白检测在子宫颈癌及其癌前病变中的临床病理学意义,并分析Gli蛋白表达与HPV16型感染的关系.方法 32例正常子宫颈上皮、71例子宫颈上皮内瘤变(CIN);其中CIN1 28例、CIN2 18例、CIN3 25例和80例子宫颈鳞状上皮癌(SCC)共183例存档蜡块选自延边大学医院、延边妇幼保健院和延边肿瘤医院病理科.应用PCR技术检测上述组织中HPV16型的感染,并用免疫组化方法在子宫颈病变组织芯片中检测Gli-1、Gli-2、Gli-3蛋白的表达情况.结果 Gli-1和Gli-2蛋白呈胞质和胞核染色,Gli-3蛋白多数呈胞质染色.在子宫颈癌和癌前病变(CIN2/3)中,Gli-1~3呈强阳性,其阳性表达率均显著高于正常子宫颈黏膜上皮.80例子宫颈癌标本中HPV16阳性率是77.5%.在子宫颈癌组织中HPV16阳性组的Gli-1蛋白的胞质阳性率(85.5%,53/62)与强阳性率(85.5%,53/62)以及Gli-2蛋白的胞质阳性率(100%)与胞核强阳性率(100%)均高于HPV16阴性组(Gli-1胞质阳性率与强阳性率均为0,Gli-2胞质阳性率和胞核强阳性率分别为0和50%),差异具有统计学意义(P均<0.05);而3种蛋白表达率与患者的年龄、淋巴结转移、肿瘤学分期和临床分期均无关.结论 Gli-1、Gli-2、Gli-3蛋白过表达可以作为子宫颈癌及其癌前病变的早期辅助诊断指标,Gli蛋白的表达水平与HPV16感染密切相关,且有望成为子宫颈癌靶向治疗的新靶点.     

p16INK4A, CDC6, and MCM5: predictive biomarkers in cervical preinvasive neoplasia and cervical cancer

AIM: To analyse and compare expression patterns of three potential biomarkers-p16(INK4A), CDC6, and MCM5-and evaluate their use as predictive biomarkers in squamous and glandular cervical preinvasive neoplasia. METHODS: Immunocytochemical analysis of p16(INK4A), MCM5, and CDC6 expression was performed on 20 normal, 38 cervical intraepithelial neoplasia 1 (CIN1), 33 CIN2, 46 CIN3, 10 squamous cell carcinoma, 19 cervical glandular intraepithelial neoplasia (cGIN), and 10 adenocarcinoma samples. Staining intensity was assessed using a 0-3 scoring system. p16(INK4A), MCM5, and CDC6 expression was also examined in ThinPrep slides exhibiting mild, moderate, and severe dyskaryosis. Human papillomavirus (HPV) was detected using a modified SYBR green assay. Fluorogenic polymerase chain reaction (PCR) and solution phase PCR were used for specific HPV typing. RESULTS: All three markers showed a linear correlation between expression and grade of dysplasia. p16(INK4A) and MCM5 protein expression was upregulated in all grades of squamous and glandular dysplasia. CDC6 protein was preferentially expressed in high grade lesions and in invasive squamous cell carcinoma. CONCLUSION: p16(INK4A) expression was closely associated with high risk HPV infection-all grades of squamous and glandular cervical lesions were immunohistochemically positive. MCM5 staining intensity was independent of high risk HPV infection, highlighting its potential as a biomarker in both HPV dependent and independent cervical dysplasia. CDC6 may be a biomarker of high grade and invasive lesions of the cervix, with limited use in low grade dysplasia. p16(INK4A) was the most reliable marker of cervical dysplasia. Combinations of dysplastic biomarkers may be useful in difficult diagnostic cases.