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Featured researches published by H. Hollema.


Journal of Clinical Oncology | 1996

Pretreatment serum squamous cell carcinoma antigen: A newly identified prognostic factor in early-stage cervical carcinoma

Jitze M. Duk; Klaas H. Groenier; H.W.A. de Bruijn; H. Hollema; K. A. ten Hoor; A.G.J. van der Zee; Jg Aalders

PURPOSE To investigate the prognostic value of pretreatment serum squamous cell carcinoma antigen (SCC-ag) levels in patients with cervical squamous cell carcinoma in relation to well-established conventional risk factors. PATIENTS AND METHODS Sera from 653 women treated for squamous cervical cancer between 1978 and 1994 were analyzed for the presence of SCC-ag and related to clinicopathologic characteristics and patient outcome using univariate and multivariate analyses. RESULTS Increased pretreatment SCC-ag levels correlated strongly with unfavorable clinicopathologic characteristics (International Federation of Gynecology and Obstetrics [FIGO] stages IB to IV [P < or = .00005]; stages IB and IIA: tumor size [P = .0236], deep stromal infiltration [P = .00009], and lymph node metastasis [P = .0001]). After multivariate analysis, elevated pretreatment serum SCC-ag levels (P = .001), lesion size (P = .043), and vascular invasion by tumor cells (P = .001) were independent predictors for the presence of lymph node metastases. In Cox regression analysis, controlling for SCC-ag, lesion size, grade, vascular invasion, depth of stromal infiltration, and lymph node status only the initial SCC-ag level had a significant independent effect on survival (P = .0152). Even in node-negative patients, the risk of recurrence was three times higher if the SCC-ag level was elevated before therapy. CONCLUSION The determination of pretreatment serum SCC-ag level provides a new prognostic factor in early-stage disease, particularly in patients with small tumor size. In future trials to assess the value of new treatment strategies, pretreatment serum SCC-ag levels can be used to help identify patients with a poor prognosis.


International Journal of Cancer | 2012

A four-gene methylation marker panel as triage test in high-risk human papillomavirus positive patients†

Jasper J.H. Eijsink; Agnes Lendvai; Valérie Deregowski; Harry G. Klip; G. Verpooten; Luc Dehaspe; G. H. de Bock; H. Hollema; W. van Criekinge; Ed Schuuring; A.G.J. van der Zee; G.B.A. Wisman

Cervical neoplasia‐specific biomarkers, e.g. DNA methylation markers, with high sensitivity and specificity are urgently needed to improve current population‐based screening on (pre)malignant cervical neoplasia. We aimed to identify new cervical neoplasia‐specific DNA methylation markers and to design and validate a methylation marker panel for triage of high‐risk human papillomavirus (hr‐HPV) positive patients. First, high‐throughput quantitative methylation‐specific PCRs (QMSP) on a novel OpenArray™ platform, representing 424 primers of 213 cancer specific methylated genes, were performed on frozen tissue samples from 84 cervical cancer patients and 106 normal cervices. Second, the top 20 discriminating methylation markers were validated by LightCycler® MSP on frozen tissue from 27 cervical cancer patients and 20 normal cervices and ROCs and test characteristics were assessed. Three new methylation markers were identified (JAM3, EPB41L3 and TERT), which were subsequently combined with C13ORF18 in our four‐gene methylation panel. In a third step, our methylation panel detected in cervical scrapings 94% (70/74) of cervical cancers, while in a fourth step 82% (32/39) cervical intraepithelial neoplasia grade 3 or higher (CIN3+) and 65% (44/68) CIN2+ were detected, with 21% positive cases for ≤CIN1 (16/75). Finally, hypothetical scenario analysis showed that primary hr‐HPV testing combined with our four‐gene methylation panel as a triage test resulted in a higher identification of CIN3 and cervical cancers and a higher percentage of correct referrals compared to hr‐HPV testing in combination with conventional cytology. In conclusion, our four‐gene methylation panel might provide an alternative triage test after primary hr‐HPV testing.


Clinical Cancer Research | 2009

Expression of epidermal growth factor receptor (EGFR) and activated EGFR predict poor response to (chemo)radiation and survival in cervical cancer

Maartje G. Noordhuis; Jasper J.H. Eijsink; K. A. ten Hoor; Frank Roossink; H. Hollema; Hjg Arts; Elisabeth Pras; J.H. Maduro; Anna K.L. Reyners; G. H. de Bock; G.B.A. Wisman; Ed Schuuring; A.G.J. van der Zee

Purpose: Activation of the epidermal growth factor receptor (EGFR) signaling pathway has been reported to induce resistance to (chemo)radiation in cancers, such as head and neck cancer, whereas EGFR-targeted agents in combination with (chemo)radiation seem to improve treatment efficacy. The aim of this study was to determine the relation between proteins involved in the EGFR pathway and response to (chemo)radiation and survival in a large, well-documented series of cervical cancer patients. Experimental Design: Pretreatment tissue samples of 375 consecutive International Federation of Gynecologists and Obstetricians stage Ib to IVa cervical cancer patients treated with (chemo)radiation between January 1980 and December 2006 were collected. Clinicopathologic and follow-up data were prospectively obtained during standard treatment and follow-up. Protein expression of EGFR, phosphorylated EGFR (pEGFR), PTEN, phosphorylated AKT, and phosphorylated extracellular signal-regulated kinase (pERK) was assessed by immunohistochemistry on tissue microarrays. Results: EGFR staining was present in 35.3%, pEGFR in 19.7%, PTEN in 34.1%, phosphorylated AKT in 4.1%, and pERK in 29.2% of tumors. pEGFR staining was related to PTEN (P = 0.001) and pERK staining (P = 0.004). EGFR staining was inversely related to PTEN (P = 0.011). In multivariate analysis, membranous staining of EGFR [hazard ratio (HR), 1.84; 95% confidence interval (95% CI), 1.20-2.82; P = 0.005] and cytoplasmic staining of pEGFR (HR, 1.71; 95% CI, 1.11-2.66; P = 0.016) were independent predictors of poor response to (chemo)radiation. Membranous EGFR staining also was an independent prognostic factor for poor disease-specific survival (HR, 1.54; 95% CI, 1.09-2.17; P = 0.014). Conclusions: EGFR and pEGFR immunostainings are frequently observed and independently associated with poor response to therapy and disease-specific survival in cervical cancer patients primarily treated by (chemo)radiation. Our data present the EGFR pathway as a promising therapeutic target in already ongoing clinical trials. (Clin Cancer Res 2009;15(23):7389–97)


British Journal of Cancer | 2008

The ErbB signalling pathway: protein expression and prognostic value in epithelial ovarian cancer

P. A. de Graeff; Anne Crijns; K. A. ten Hoor; Harry Klip; H. Hollema; Karin A. Oien; John M.S. Bartlett; G.B.A. Wisman; G. H. de Bock; E.G.E. de Vries; S de Jong; A.G.J. van der Zee

Ovarian cancer is the most frequent cause of death from gynaecological cancer in the Western world. Current prognostic factors do not allow reliable prediction of response to chemotherapy and survival for individual ovarian cancer patients. Epidermal growth factor receptor (EGFR) and HER-2/neu are frequently expressed in ovarian cancer but their prognostic value remains unclear. In this study, we investigated the expression and prognostic value of EGFR, EGFR variant III (EGFRvIII), HER-2/neu and important downstream signalling components in a large series of epithelial ovarian cancer patients. Immunohistochemical staining of EGFR, pEGFR, EGFRvIII, Her-2/neu, PTEN (phosphatase and tensin homologue deleted on chromosome 10), total and phosphorylated AKT (pAKT) and phosphorylated ERK (pERK) was performed in 232 primary tumours using the tissue microarray platform and related to clinicopathological characteristics and survival. In addition, EGFRvIII expression was determined in 45 tumours by RT–PCR. Our results show that negative PTEN immunostaining was associated with stage I/II disease (P=0.006), non-serous tumour type (P=0.042) and in multivariate analysis with a longer progression-free survival (P=0.015). Negative PTEN staining also predicted improved progression-free survival in patients with grade III or undifferentiated serous carcinomas (P=0.011). Positive pAKT staining was associated with advanced-stage disease (P=0.006). Other proteins were expressed only at low levels, and were not associated with any clinicopathological parameter or survival. None of the tumours were positive for EGFRvIII. In conclusion, our results indicate that tumours showing negative PTEN staining could represent a subgroup of ovarian carcinomas with a relatively favourable prognosis.


Journal of Clinical Oncology | 1998

Telomerase activity as a biomarker for (pre)neoplastic cervical disease in scrapings and frozen sections from patients with abnormal cervical smear.

G.B.A. Wisman; H. Hollema; S de Jong; J. Ter Schegget; Steven P. Tjong-A-Hung; Marcel H. J. Ruiters; Mindert Krans; E.G.E. de Vries; A.G.J. van der Zee

PURPOSE To evaluate the diagnostic value of semi-quantitative telomerase activity assessment in cervical scrapings together with human papillomavirus (HPV) typing for detection of (pre)neoplastic cervical lesions and to compare telomerase activity in cervical scrapings and frozen specimens from the same patients. PATIENTS AND METHODS A cross-sectional study was performed in 161 patients referred for an abnormal cervical cytology report. In cervical scrapings, telomerase activity was determined by modified telomere repeat amplification protocol (TRAP) assay and HPV typing by polymerase chain reaction (PCR) with general and type-specific primers. Final diagnosis was made by pathologic examination of biopsy and/or loop excision specimens. RESULTS Telomerase activity was detectable in assessable scrapings from one of nine (11%) patients without cervical intraepitheleal neoplasia (CIN), in three of 26 (12%) with CIN I, eight of 35 (22%) with CIN II, 18 of 62 (29%) with CIN III, and four of 13 (31%) with cancer. Sensitivity and negative predictive value of the TRAP assay for CIN II/III and cancer lesions were 25% and 28%, respectively, while specificity for no CIN or CIN I was 89%. In representative frozen sections, frequency of detectable telomerase activity was related to grade of CIN/cancer; none of 21 normal cervices, none of two CIN I, two of 12 (17%) CIN II, 10 of 31 (32%) CIN III, and 18 of 21 (86%) cervical cancer lesions were telomerase-positive (P < .0005). Telomerase activity levels in paired scrapings and frozen sections appeared to be only weakly related; telomerase-positive sections with negative scrapings and vice versa (only in CIN III) were observed. In oncogenic HPV-negative scrapings (n = 14), no telomerase activity was detected, but in frozen sections, telomerase activity levels appeared to be unrelated to presence of specific HPV types. CONCLUSION Telomerase activity is more frequent in higher grade CIN/cervical cancer lesions. Telomerase activity assessment in cervical scrapings has a low sensitivity for CIN II/III and/or cervical cancer and does not appear to be useful in primary screening for cervical cancer. However, increased telomerase activity in frozen CIN sections may be a possible marker of progressive disease.


Tumor Biology | 1998

THE CLINICAL VALUE OF SQUAMOUS CELL CARCINOMA ANTIGEN IN CANCER OF THE UTERINE CERVIX

H.W.A. de Bruijn; Jitze M. Duk; A.G.J. van der Zee; Elisabeth Pras; Phb Willemse; H. Boonstra; H. Hollema; Mje Mourits; E.G.E. de Vries; Jg Aalders

A review is given of the clinical use and interpretation of serum tumor marker levels during the treatment of patients with cancer of the uterine cervix. Pretreatment serum squamous cell carcinoma (SCC) antigen provides a new prognostic factor in early stage squamous cell carcinoma of the uterine cervix. Elevated serum values of SCC antigen at the time of diagnosis of stage IB and IIA cervical cancer indicate a 3 × increased risk of tumor recurrence, independent of tumor diameter, grade or the presence of lymph node metastases. High pretreatment SCC antigen levels could therefore be used to select ‘high-risk’ patients for adjuvant therapy. Measurement of the serum SCC antigen levels provides a means of monitoring the effect of therapy. During the postoperative follow-up of patients with localized cancer of the uterine cervix the measurement of SCC antigen can lead to the early detection of recurrent disease when curative therapy is still an option. The profile of serum SCC antigen parallels the response to radiotherapy and provides a way of evaluating the effectiveness of chemotherapy. Serial measurements after surgery and during radio- and chemotherapy demonstrate that SCC antigen is a more sensitive marker for recognizing tumor progression or recurrence than CYFRA-21.1, TPS or CEA. When following up patients with a pure adenocarcinoma of the cervix measurements of serum CA 125 and CEA are preferred over SCC antigen measurements.


Journal of Clinical Pathology | 2003

Detection of telomerase, its components, and human papillomavirus in cervical scrapings as a tool for triage in women with cervical dysplasia

Nathalie Reesink-Peters; Marco N. Helder; G.B.A. Wisman; Aj Knol; S Koopmans; H. M. Boezen; Eduardus Maria Dominicus Schuuring; H. Hollema; E. de Vries; S de Jong; A.G.J. van der Zee

Aim: To examine whether the detection of either telomerase and its components or high risk human papillomavirus (HPV) are of value in predicting the presence of cervical intraepithelial neoplasia (CIN) grade II/III in women referred because of cervical cytology reports showing at most moderate dyskaryosis. Methods: Cervical scrapings of 50 women referred with cytological borderline, mild, or moderate dyskaryosis were analysed. Telomerase activity was assessed by a commercially available telomere repeat amplification protocol assay and its components human telomerase RNA (hTR) and human telomerase reverse transcriptase (hTERT) were assessed by reverse transcriptase polymerase chain reaction (PCR). HPV was detected by GP5+/6+ PCR enzyme immunosassay. Histological findings on colposcopy guided biopsies or excised cervical tissue were regarded as the final pathological diagnosis. The sensitivity and specificity for detecting CIN II/III were calculated. Results: Twenty eight women were diagnosed with CIN II/III. Telomerase activity was detected in none, hTR in 88%, hTERT in 23%, and high risk HPV was detected in 79% of these women. As a diagnostic test none of the described analyses combined a sensitivity of at least 90% with a specificity ≥ 90%. Despite the small numbers, calculation of the 95% confidence intervals excluded a combined sensitivity and specificity of at least 90% for all of the evaluated parameters. Conclusions: Neither detection of telomerase or its components, nor detection of high risk HPV seem suitable for the triage of women with borderline, mild, and moderate cytological dyskaryosis.


British Journal of Cancer | 1992

Glutathione S-transferase activity and isoenzyme composition in benign ovarian tumours, untreated malignant ovarian tumours, and malignant ovarian tumours after platinum/cyclophosphamide chemotherapy.

A.G.J. van der Zee; B. van Ommen; Coby Meijer; H. Hollema; P.J. van Bladeren; E.G.E. de Vries

Glutathione S-transferase (GST) isoenzyme composition, isoenzyme quantities and enzymatic activity were investigated in benign (n = 4) ovarian tumours and malignant ovarian tumours, before (n = 20) and after (n = 16) chemotherapy. Enzymatic activity of GST in cytosols was measured by determining 1-chloro-2,4-dinitrobenzene conjugation with glutathione, cytosolic GST subunits were determined by wide pore reversed phase HPLC, using a S-hexylglutathione-agarose affinity column, and isoelectric focussing. Both GST activity and GST pi amount were not related to histopathologic type, differentiation grade, or tumour volume index in untreated malignant tumours. GST isoenzyme patterns were identical in benign tumours and malignant tumours before and after platinum/cyclophosphamide chemotherapy, while GST pi was the predominant transferase. Mean GST activity and GST pi amount were decreased (P < 0.05) in malignant ovarian tumours after platinum/cyclophosphamide chemotherapy compared to untreated ovarian malignant tumours. No relation was found in untreated ovarian tumours between GST pi amount and response to platinum/cyclophosphamide chemotherapy. Thus, within the limitations of the current study no arguments were found for a role of GST in in vivo drug resistance of malignant ovarian tumours to platinum/cyclophosphamide chemotherapy.


British Journal of Cancer | 2006

Factors influencing p53 expression in ovarian cancer as a biomarker of clinical outcome in multicentre studies

P. A. de Graeff; Jacqueline A. Hall; Anne Crijns; G. H. de Bock; James Paul; Karin A. Oien; K. A. ten Hoor; S de Jong; H. Hollema; John M.S. Bartlett; Robert Brown; A.G.J. van der Zee

The prognostic impact of p53 immunostaining in a large series of tumours from epithelial ovarian cancer patients in a two-centre study was analysed. The study population (n=476) comprised of a retrospective series of 188 patients (Dutch cohort) and a prospective series of 288 patients (Scottish cohort) enrolled in clinical trials. P53 expression was determined by immunohistochemistry on tissue microarrays. Association with progression-free survival (PFS) and overall survival (OS) was analysed by univariate and multivariate Cox regression analysis. Aberrant p53 overexpression was significantly associated with PFS in the Dutch and Scottish cohorts (P=0.001 and 0.038, respectively), but not with OS in univariate analysis. In multivariate analysis, when the two groups were combined and account taken of clinical factors and country of origin of the cohort, p53 expression was not an independent prognostic predictor of PFS or OS. In this well-powered study with minimal methodological variability, p53 immunostaining is not an independent prognostic marker of clinical outcome in epithelial ovarian cancer. The data demonstrate the importance of methodological standardisation, particularly defining patient characteristics and survival end-point data, if biomarker data from multicentre studies are to be combined.


Scandinavian Journal of Gastroenterology | 2003

Dysplasia in fundic gland polyps is associated with nuclear beta-catenin expression and relatively high cell turnover rates

Mathilde Jalving; Jan J. Koornstra; W. Boersma-van Ek; S de Jong; A Karrenbeld; H. Hollema; E.G.E. de Vries; Jh Kleibeuker

Background: Fundic gland polyps (FGPs) occur in both syndromic and sporadic form. Syndromic FGPs arise through mutations in the adenomatous polyposis coli (APC) gene, whereas sporadic FGPs are caused by

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A.G.J. van der Zee

University Medical Center Groningen

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E.G.E. de Vries

University Medical Center Groningen

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S de Jong

University of Groningen

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Hans W. Nijman

University Medical Center Groningen

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Phb Willemse

University of Groningen

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J.A. de Hullu

Radboud University Nijmegen

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Agj van der Zee

University Medical Center Groningen

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Jan J. Koornstra

University Medical Center Groningen

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