Ruediger Ridder

Klinikum der Stadt Wolfsburg, Wolfsburg, Lower Saxony, Germany

Are you Ruediger Ridder?

Claim your profile

Publications (50)213.34 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background:Women with borderline/mildly dyskaryotic (BMD) cytology smears are currently followed up with repeat testing at 6 and 18 months. The objective of this study is to analyse the cross-sectional and longitudinal performance of p16/Ki-67 dual-stained cytology for the detection of cervical intraepithelial neoplasia (CIN) grade 3 or worse (CIN3+) and CIN2+ in women with BMD, and to compare the results with baseline human papillomavirus (HPV) testing.Methods:Conventional Pap cytology specimens of 256 women with BMD were dual stained for p16/Ki-67 retrospectively, and compared with baseline HPV results and long-term follow-up results.Results:p16/Ki-67 dual-stained cytology showed a sensitivity of 100%, a specificity of 64.4% and a negative predictive value (NPV) of 100.% for CIN3+. Human papillomavirus testing demonstrated similar sensitivity (96.3%), and NPV (99.1%), but a significantly lower specificity (57.6%; P=0.024) for CIN3+. Sensitivity, specificity and NPV for CIN2+ of dual-stained cytology were 89.7%, 73.1% and 95.1%, respectively, which was similar when compared with HPV testing. Dual-stained cytology showed a significant lower referral rate than HPV testing (43.6% vs 49.1%; P=0.043). During long-term follow-up, no CIN3+ lesions developed in HPV-positive, dual-stained negative women.Conclusions:Comparable sensitivity and NPV of dual-stained cytology for CIN3+, combined with a significantly higher specificity, makes p16/Ki-67 dual-stained cytology a viable alternative to HPV testing for triaging BMD.British Journal of Cancer advance online publication, 11 February 2014; doi:10.1038/bjc.2014.34
    British Journal of Cancer 02/2014; · 5.08 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Pap cytology is known to be more specific but less sensitive than testing for human papillomavirus (HPV) for the detection of high-grade cervical intraepithelial neoplasia (CIN2+). We assessed whether p16/Ki-67 dual-stained cytology, a biomarker combination indicative of transforming HPV infections, can provide high sensitivity for CIN2+ in screening while maintaining high specificity. Results were compared with Pap cytology and HPV testing. A total of 27349 women 18 years or older attending routine cervical cancer screening were prospectively enrolled in five European countries. Pap cytology, p16/Ki-67 immunostaining, and HPV testing were performed on all women. Positive test results triggered colposcopy referral, except for women younger than 30 years with only positive HPV test results. Presence of CIN2+ on adjudicated histology was used as the reference standard. Two-sided bias-corrected McNemar P values were determined. The p16/Ki-67 dual-stained cytology positivity rates were comparable with the prevalence of abnormal Pap cytology results and less than 50% of the positivity rates observed for HPV testing. In women of all ages, dual-stained cytology was more sensitive than Pap cytology (86.7% vs 68.5%; P < .001) for detecting CIN2+, with comparable specificity (95.2% vs 95.4%; P = .15). The relative performance of the tests was similar in both groups of women: younger than age 30 and 30 years or older. HPV testing in women 30 years or older was more sensitive than dual-stained cytology (93.3% vs 84.7%; P = .03) but less specific (93.0% vs 96.2%; P < .001). The p16/Ki-67 dual-stained cytology combines superior sensitivity and noninferior specificity over Pap cytology for detecting CIN2+. It suggests a potential role of dual-stained cytology in screening, especially in younger women where HPV testing has its limitations.
    CancerSpectrum Knowledge Environment 10/2013; · 14.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Diffuse overexpression of p16(INK4a) in basal and parabasal cells of cervical epithelium is a hallmark of human papillomavirus-mediated transformation. Focal p16(INK4a) expression is occasionally observed in nondysplastic epithelium. In normal cells, expression of p16(INK4a) triggers cell cycle arrest. However, cells undergoing transformation in intraepithelial lesions actively proliferate. To prove that the different expression patterns of p16(INK4a) , i.e., focal versus diffuse, reflect biologically different entities, we hypothesized that p16(INK4a) -positive cells in epithelia displaying focal p16(INK4a) expression pattern do not coexpress proliferation-associated Ki-67 protein, while p16(INK4a) -positive cells in lesions with diffuse p16(INK4a) expression may do. A total of 138 cervical cone biopsies were stained for the expression of p16(INK4a) and Ki-67 using a primary antibody cocktail. All metaplastic lesions (n = 21) displayed focal staining for p16(INK4a) , and in all of these lesions p16(INK4a) -positive cells were found to be negative for Ki-67 expression. Diffuse expression of p16(INK4a) was observed in 12/21 (57.1%) cervical intraepithelial neoplasia (CIN) 1 lesions, all of them simultaneously showed Ki-67 immunoreactivity in a large proportion of p16(INK4a) -positive cells. Seventeen of 23 (73.9%) CIN2 lesions and all 27 (100%) CIN3/carcinoma in situ (CIS) as well as all 46 (100%) carcinoma cases displayed diffuse and combined expression of p16(INK4a) and Ki-67. Coexpression of Ki-67 and p16(INK4a) in the same cell is entirely restricted to cervical lesions displaying diffuse p16(INK4a) expression, whereas in lesions with focal p16(INK4a) expression, p16(INK4a) -expressing cells are negative for Ki-67. Thus, diffuse expression of p16(INK4a) reflects lesions with proliferation-competent cells, while p16(INK4a) -expressing cells associated with focal expression patterns are cell cycle arrested.
    International Journal of Cancer 03/2011; 130(2):388-94. · 6.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The objective of this study was to analyze the diagnostic performance of a newly established immunocytochemical dual-stain protocol, which simultaneously detects p16(INK4a) and Ki-67 expression in cervical cytology samples, for identifying high-grade cervical intraepithelial neoplasia (CIN2+) in women with Papanicolaou (Pap) cytology results categorized as atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesions (LSIL). Residual liquid-based cytology material from 776 retrospectively collected ASCUS/LSIL cases that were available from a recent study evaluating p16 cytology and HPV testing were subjected to p16/Ki-67 dual staining. The presence of 1 or more double-immunoreactive cell(s) was regarded as a positive test outcome, irrespective of morphology. Test results were correlated to histology follow-up. Sensitivity of p16/Ki-67 dual-stain cytology for biopsy-confirmed CIN2+ was 92.2% (ASCUS) and 94.2% (LSIL), while specificity rates were 80.6% (ASCUS) and 68.0% (LSIL), respectively. Similar sensitivity/specificity profiles were found for both age groups of women aged <30 years versus women aged ≥30 years. Dual-stain cytology showed comparable sensitivity, but significantly higher specificity, when compared with human papillomavirus (HPV) testing. The results of this study show that p16/Ki-67 dual-stain cytology provided a high sensitivity for the detection of underlying CIN2+ in women with ASCUS or LSIL Pap cytology results, comparable to the rates previously reported for HPV testing and p16 single-stain cytology. However, the specificity of this morphology-independent interpretation of p16/Ki-67 dual-stain cytology testing was further improved compared with the earlier p16 single-stain cytology approach, which required morphology interpretation, and it is significantly higher when compared with HPV testing.
    Cancer Cytopathology 03/2011; 119(3):158-66. · 4.43 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Testing for human papillomavirus (HPV) has been shown to increase the sensitivity and negative predictive value for detection of high-grade cervical intraepithelial neoplasia (CIN2+), either when used in conjunction with Pap cytology testing or alone. However, there is no satisfying clinical management algorithm for women testing Pap negative/HPV positive. We therefore evaluated the clinical utility of a novel dual biomarker-based approach (p16/Ki-67 Dual-stained cytology) for the identification of CIN2+ in women with Pap negative/HPV positive screening results, without the need to refer all women to immediate colposcopy. All women aged ≥30 enrolled during 2007/2008 into a regional prospective Pap/HPV co-testing screening pilot project and tested Pap negative, but positive for HPV (n=425) were included in the analysis. p16/Ki-67 Dual-stained cytology was performed from residual cellular material available from the liquid-based cytology vial collected during the initial Pap/HPV co-testing screening visit. Results were correlated to the presence of CIN2+ confirmed during preliminary follow-up. p16/Ki-67 Dual-stained cytology tested positive at baseline in 108 out of 425 (25.4%) Pap negative/HPV positive cases. Sensitivity of Dual-stain testing for the detection of biopsy-confirmed CIN2+ during preliminary follow-up within the group of Pap negative/HPV positive women was 91.9% for CIN2+ (34/37 cases), and 96.4% for CIN3+ (27/28 cases). Specificity was 82.1% for CIN2+ on biopsy, and 76.9% for CIN3+, respectively. Triaging Pap negative/HPV positive screening test results with p16/Ki-67 Dual-stained cytology may identify women with a high probability of underlying CIN2+ and may efficiently complement HPV-based screening programs to prevent cervical cancer.
    Gynecologic Oncology 03/2011; 121(3):505-9. · 3.93 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We analyzed the performance of p16(INK4a) immunocytochemistry on a series of 810 retrospectively collected atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL) cases with available biopsy follow-up data, including 94 cases of cervical intraepithelial neoplasia (CIN) 2 and 128 cases of CIN 3. Human papillomavirus (HPV) testing was performed from the same residual liquid-based cytologic specimen, and results for both tests were correlated with histologic follow-up data. Sensitivity values for high-grade CIN (HGCIN) confirmed on biopsy within 6 months were 92.6% (ASC-US) and 92.2% (LSIL) for cytotechnologists' reviews of p16 cytology and 90.1% (ASC-US) and 95.7% (LSIL) for HPV testing. Sensitivity rates of initial pathologists' reviews were slightly lower, 76.4% to 80.1%, with levels comparable to cytotechnologists' results after adjudication. The specificity of p16 cytology for HGCIN detection was significantly higher than for HPV testing for cytotechnologists and pathologists: 63.2% to 71.1% (p16 cytology) vs 37.8% for HPV in ASC-US (P < .001) and 37.3% to 53.3% (p16 cytology) vs 18.5% for HPV in LSIL (P < .001). This evaluation of the diagnostic performance of p16 cytology confirms the potential of this stain for the efficient triage of ASC-US and LSIL cytologic results.
    American Journal of Clinical Pathology 07/2010; 134(1):12-21. · 2.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    American Journal of Clinical Pathology 03/2010; 133(3):395-406. · 2.88 Impact Factor
  • Rüdiger Ridder, Hermann Gram
    [Show abstract] [Hide abstract]
    ABSTRACT: Rabbits provide an interesting alternative to antibodies derived from the murine system. Furthermore, rabbits show an exceptional feature with respect to the mechanisms that are used for the generation of antibody diversity, i.e. a single VH gene that is preferentially used, and the diversity of the antibody repertoire being mainly generated by gene conversion and hypermutation, which facilitates the molecular cloning of the rabbit immune repertoire. In this chapter, the general strategy for the combinatorial cloning of the variable heavy and light chain immunoglobulin repertoire of rabbits for the subsequent phage display of rabbit scFv antibody fragments is described.
    12/2009: pages 115-123;
  • [Show abstract] [Hide abstract]
    ABSTRACT: The low sensitivity of cytology and low specificity of human papillomavirus testing prompts searching for more accurate cervical cancer screening strategies. Our goal was to evaluate an ELISA-based test for p16(INK4a). 1,781 women undergoing routine screening provided cervical specimens for p16(INK4a) ELISA (original and enhanced versions of a prototype), liquid-based cytology, and Hybrid Capture II (hc2) testing. All women with a positive result and a random sample of those with negative results on all tests were referred for histologic diagnosis. Cervical intraepithelial neoplasia grade >or=3 (>or=CIN3) was the main outcome. The original analysis included all >or=CIN3 outcomes (n = 28). The a posteriori analysis was used to represent clinically relevant results with >or=CIN3 as outcomes only when detected after a positive screening test (n = 27). Participants had a median age of 23 years. The prevalence of high-risk human papillomavirus DNA was 30.6%. In a posteriori analyses, the sensitivity and specificity for p16(INK4a) ELISA (>or=8 pg/mL cut-point), cytology, and hc2 were 50.9%, 58.1%, and 100.0%, respectively, and 90.4%, 89.3%, and 69.2%, respectively. Referral to colposcopy of women with positive results for hc2 and p16(INK4a) (enhanced ELISA, >or=6 pg/mL cut-point) had a sensitivity of 91.8% (95% confidence interval, 79.1-100.0%) and specificity of 86.0% (95% confidence interval, 82.0-89.0%). Results of the original analyses had similar specificity but substantially lower sensitivity due to the strong influence of the single CIN3 case with completely negative screening results. An enhanced version of this prototypic p16(INK4a) ELISA showed promise in screening, particularly when combined with hc2.
    Cancer Epidemiology Biomarkers &amp Prevention 11/2009; 18(11):3008-17. · 4.56 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The quality of cervical histopathology is critical to cervical cancer prevention, cancer treatment, and research programs. On the basis of the histology results further patient management is determined. However, the diagnostic interpretation of histologic hematoxylin-eosin (H&E)-stained slides is affected by substantial rates of discordance among pathologists. Overexpression of the cyclin-dependent kinase inhibitor p16INK4a, a cell cycle regulating protein, has been shown to be strongly correlated with dysplastic lesions of the cervix uteri. In this study, we assessed whether p16INK4a immunohistochemistry may increase the performance of pathologists in diagnosing squamous lesions in cervical punch and cone biopsies. When using a consecutive p16INK4a-stained slide in conjunction to the H&E-stained slide, interobserver agreement between 6 pathologists improved significantly for both cervical punch and cone biopsies (P < 0.001). For punch biopsies (n = 247), kappa value increased from 0.49 (moderate agreement) to 0.64 indicating substantial agreement, and interobserver agreement for cone biopsies (n = 249) improved from 0.63 (conventional H&E slide reading) to 0.70 when H&E-stained slides were read conjunctively with p16INK4a-stained slides. In comparison to a common consensus diagnosis established by 3 independent experts, 4 pathologists reached an improvement with the conjunctive p16INK4a test, 2 of them showing significantly better agreement (P < 0.001 and P = 0.002, respectively), p16INK4a immunohistochemistry as an adjunct to conventional H&E-stained specimens thus contributes to a more reproducible diagnosis of cervical intraepithelial neoplasia and may be a valuable aid for the interpretation of cervical histology.
    American Journal of Surgical Pathology 05/2008; 32(4):502-12. · 4.87 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: p16(INK4a), a cell cycle regulation protein, accumulates in abnormal epithelial cells infected with high-risk human papilloma virus (HPV). In immunostaining studies, p16(INK4a) has shown potential as a marker of high grade cervical intraepithelial neoplasia (CIN) and invasive cervical cancer. To evaluate its potential use in cervical cancer screening, we conducted a feasibility study to compare the performance of a new enzyme linked immunosorbant assay (ELISA) for p16(INK4a) (mtm laboratories, Heidelberg, Germany) to that of the Hybrid Capture 2 (hc2) test for high-risk HPV DNA for the detection of CIN3. Three hundred and nineteen women were referred from Western Washington Planned Parenthood clinics for colposcopy examination and cervical biopsy because of abnormal Pap test results. Cervical samples were obtained from study participants for p16(INK4a) ELISA, liquid-based cytology and hc2. The order (first and second) for obtaining samples for cervical cytology and p16(INK4a) ELISA changed with every other subject. Concentrations of p16(INK4a) protein were higher when the sample was taken before the cytology. The sensitivity of p16(INK4a) ELISA (concentration > or = 8 units/ml) taken as first sample was 90.0% for CIN3, and the sensitivity of HC2 taken as a second sample was 85%. In the same group, the specificity of p16(INK4a) ELISA (46.9%) was slightly better than hc2 (35.4%) Results from this proof-of-concept study suggest that p16(INK4a) ELISA has a similar sensitivity and slightly better specificity for CIN3 compared to hc2. These findings support proceeding with a larger study with samples from a population of women presenting for routine cytology screening.
    International Journal of Cancer 07/2007; 120(11):2435-8. · 6.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The purpose of the study is to test the hypothesis that expression of cell cycle regulatory proteins p16(INK4a) and pRb is significantly associated with prognosis in ovarian carcinomas. We performed immunohistochemical analysis of p16(INK4a) and pRb expression and correlated with survival in a series of 300 patients with FIGO stage IIb-IV ovarian carcinoma which were enrolled in a randomized prospective trial evaluating two different platinum and paxlitaxel chemotherapy combinations after radical surgery. p16(INK4a) negative tumours (17/300; 6%) had a significantly worse prognosis (univariate analysis, P<0.001; multivariate analysis: odds ratio 2.41, P=0.009). Among p16(INK4a)-positive tumours (283 out of 300; 94%), survival was better for patients with intermediate expression as compared to low or high expression levels (P=0.001). High expression levels of pRb were associated with an incremental deterioration of prognosis (univariate analysis, P=0.004; multivariate analysis: odds ratio 2.98, P=0.002). This observation held also true in the subgroup of optimally debulked patients (n=82), in whom the most important established prognostic factor, postoperative residual tumour cannot be applied. In conclusion p16(INK4a) and pRb are independent prognostic factors in advanced-stage ovarian carcinomas after radical surgery and postoperative chemotherapy. High pRb expression is a significant prognosticator in optimally debulked patients and may hold potential for subgroup stratification in postoperative treatment.
    British Journal of Cancer 02/2007; 96(2):306-13. · 5.08 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Current cervical cancer screening approaches are based on cytology supplemented by human papillomavirus (HPV) testing in some settings. Whereas cytology is laborious and depends on the cytologists' experience, HPV testing has limited specificity when it is used to detect high-grade lesions. A dichotomous test to identify high-grade lesions with greater specificity may be a useful tool for cervical cancer screening. p16(INK4a) is a cell-cycle regulator that has demonstrated strong overexpression in cervical precancer cells and cervical cancer induced by the deregulated expression of HPV oncogenes. The authors used a sandwich enzyme-linked immunosorbent assay (ELISA) to quantify the amount of solubilized p16(INK4a) protein in lysates that were prepared from cervical samples to detect high-grade cervical lesions. In total, 187 specimens that were obtained after sampling for conventional cytology in women who attended a cervical colposcopy clinic were analyzed. Seventy-six women underwent a biopsy, and 45 of those women showed histologically confirmed, high-grade cervical intraepithelial neoplasia. For 76 women with biopsy-proven diagnoses, receiver operating characteristic (ROC) analysis of different cutoff values showed an area under the ROC curve of 0.89 for the detection of high-grade cervical dysplasia. At a cutoff value of 8 U/mL, the sensitivity of the p16(INK4a) ELISA for detecting high-grade dysplastic cervical lesions was 96%. The data obtained in this study suggested that ELISA-based quantification of solubilized p16(INK4a) protein may have high sensitivity for detecting cervical precancer. Further population-based studies will be necessary to analyze the specificity and predictive values of p16(INK4a) protein quantification in cervical samples.
    Cancer 12/2006; 107(9):2307-13. · 5.20 Impact Factor
  • Ruediger Ridder, Marcus J Trunk, Giovanni Negri
    Diagnostic Cytopathology 08/2006; 34(7):512-4; author reply 515. · 1.49 Impact Factor
  • Journal of Lower Genital Tract Disease - J LOW GENIT TRACT DIS. 01/2006; 10(3).
  • Journal of Lower Genital Tract Disease - J LOW GENIT TRACT DIS. 01/2006; 10(3):170-171.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The chromosomal translocation t(12;16)(q13;p11) is a common genetic alteration in myxoid and round-cell liposarcomas. It results in transcription of various chimeric FUS/CHOP fusion transcripts that encode different oncogenic proteins. Recent reports suggest that these may have different neoplastic transformation activities. To audit this hypothesis, we transfected expression plasmids for the two major variant FUS/CHOP transcripts I and II in NIH 3T3 cells and determined the number of outgrowing foci as well as their growth potential in soft agar. In addition, we compared tumour growth in nude mice upon subcutaneous injection of the respective transfectants. No significant differences in transformation assays in vitro and in vivo were observed, suggesting that both variant transcripts confer comparable transforming activities. The histopathological picture of tumours derived from both cell populations resembles high-grade spindle cell sarcomas. This suggests that both FUS/CHOP variants cause similar patterns of differential gene expression. This hypothesis was confirmed by mRNA-expression profiles of the respective cell clones. Strong overexpression of the pentaxin-related gene (PTX), the osteoblast-specific factor 2 (osf-2), the basic Kruppel-like factor (bklf), the leucoprotease inhibitor, and the cyclophilin B were observed in both types of FUS/CHOP-transfected cell clones. Taken together, our data suggest that different FUS/CHOP variants cause transformation of mesenchymal cells via the same pathways with comparable efficacy.
    Oncogene 10/2004; 23(40):6798-805. · 7.36 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Due to the high prevalence of cancer-associated types of human papillomavirus (HPV) and the poorly reproducible histologic classification of low-grade lesions, identifying infected women at highest risk for cancer prior to neoplastic progression remains a challenge. We therefore explored the utility of p16INK4a immunostaining as a potential diagnostic and prognostic biomarker for cervical neoplasia using paraffin-embedded tissue blocks (punch biopsies and loop electrosurgical excision procedures) obtained from women referred to colposcopy during the enrollment phase of the Guanacaste Project (1993 to 1994). All blocks from 292 women selected by HPV status (HPV negative, nononcogenic HPV positive, or oncogenic HPV positive) and representing the diagnostic spectrum of the population [normal to precancer: cervical intraepithelial neoplasia (CIN) 3] were immunostained for p16INK4a using the p16INK4a research kit based on the monoclonal antibody clone E6H4 (MTM Laboratories, Heidelberg, Germany). For CIN3, the sensitivity of diffuse p16INK4a immunostaining was 100% and the specificity was 95%. For CIN2, the sensitivity and specificity for diffuse staining were 81.1% and 95.4%, respectively. Generalized to the 10,000-woman cohort, this translated to positive predictive value and negative predictive value of 13.9% and 100% for CIN3, respectively, and 20.4% and 99.7% for CIN2 or CIN3, respectively. Of women with an initial diagnosis of less than CIN2 for whom follow-up data for up to 5 to 7 years were available, 44% with diffuse staining developed persistent infection (CIN2 or CIN3). Whereas our data support the diagnostic potential for p16INK4a, further prospective studies with detailed follow-up determining the prognostic capacity of this marker are needed.
    Cancer Epidemiology Biomarkers &amp Prevention 09/2004; 13(8):1355-60. · 4.56 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: P16INK4a overexpression has been identified as a specific biomarker in high-risk human papillomavirus (HPV)-infected cervical (pre)cancer lesions. To evaluate the overexpression of this cyclin-dependent kinase inhibitor in skin tumors depending on HPV infections, we analyzed normal skin, benign skin disease, and skin cancer specimens. Biopsies of 23 patients with normal histology (3), psoriasis (2), verrucae vulgaris (2), actinic keratoses (5), squamous cell carcinoma (SCC) in situ (3), Bowen's carcinoma (1), and SCC (7) were analyzed. Specimens of 23 patients were immunostained using the monoclonal antibody E6H4 specific for p16INK4a. HPV status was assessed by a polymerase chain reaction (PCR) system to detect all currently known HPV types. MY (MY09/MY11 and MYN9/MYN10)-, CP (CP65/CP70 and CP66/CP69)-nested PCR, and three single PCR methods CN1, CN3, and CN4 were used in a first step, and HPV typing was performed by restriction fragment length polymorphism analysis. Only beta-globin-positive patients were included in this study. HPV DNA was detected in all actinic keratoses, SCC in situ, Bowen's carcinoma, and SCC, in 50% (one of two) of verrucae vulgaris, in 66% (two of three) of normal skin, and in none of two psoriasis. P16INK4a expression was not detected in normal skin, psoriasis, and verrucae vulgares. Overexpression of p16INK4a was detected in a subset of dysplastic cells (10% to 80%) of all skin (pre)cancer lesions such as actinic keratoses, SCC in situ, Bowen's carcinoma, and SCC infected with HPV independent of sun exposure. P16INK4a appears to be overexpressed in a portion of dysplastic cells from actinic keratoses and SCC. Further studies to examine the association of HPV infection and the overexpression of p16INK4a are warranted.
    Dermatologic Surgery 04/2004; 30(3):409-14. · 1.87 Impact Factor
  • Pathology Research and Practice - PATHOL RES PRACT. 01/2004; 200(4):357-357.

Publication Stats

2k Citations
213.34 Total Impact Points


  • 2011
    • Klinikum der Stadt Wolfsburg
      Wolfsburg, Lower Saxony, Germany
  • 1997–2011
    • Universität Heidelberg
      • • Institute of Pathology (Mannheim)
      • • Department of Pathology
      • • Department of Spine Surgery
      Heidelberg, Baden-Wuerttemberg, Germany
  • 2010
    • North Bristol NHS Trust
      Bristol, England, United Kingdom
    • Laboratoire CERBA
      Île-de-France, France
  • 2004
    • National Cancer Institute (USA)
      Maryland, United States
  • 2001
    • Max-Delbrück-Centrum für Molekulare Medizin
      Berlín, Berlin, Germany