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Dive into the research topics where Theo J.M. Helmerhorst is active.

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Featured researches published by Theo J.M. Helmerhorst.


The New England Journal of Medicine | 2008

Treatment of Vulvar Intraepithelial Neoplasia with Topical Imiquimod

Manon van Seters; Marc van Beurden; Fiebo J. ten Kate; Ilse Beckmann; Patricia C. Ewing; Marinus J.C. Eijkemans; Marjolein J. Kagie; Chris J. L. M. Meijer; Neil K. Aaronson; Alex Kleinjan; Claudia Heijmans-Antonissen; F. Zijlstra; Matthé P.M. Burger; Theo J.M. Helmerhorst

BACKGROUND Alternatives to surgery are needed for the treatment of vulvar intraepithelial neoplasia. We investigated the effectiveness of imiquimod 5% cream, a topical immune-response modulator, for the treatment of this condition. METHODS Fifty-two patients with grade 2 or 3 vulvar intraepithelial neoplasia were randomly assigned to receive either imiquimod or placebo, applied twice weekly for 16 weeks. The primary outcome was a reduction of more than 25% in lesion size at 20 weeks. Secondary outcomes were histologic regression, clearance of human papillomavirus (HPV) from the lesion, changes in immune cells in the epidermis and dermis of the vulva, relief of symptoms, improvement of quality of life, and durability of response. Reduction in lesion size was classified as complete response (elimination), strong partial response (76 to 99% reduction), weak partial response (26 to 75% reduction), or no response (< or =25% reduction). The follow-up period was 12 months. RESULTS Lesion size was reduced by more than 25% at 20 weeks in 21 of the 26 patients (81%) treated with imiquimod and in none of those treated with placebo (P<0.001). Histologic regression was significantly greater in the imiquimod group than in the placebo group (P<0.001). At baseline, 50 patients (96%) tested positive for HPV DNA. HPV cleared from the lesion in 15 patients in the imiquimod group (58%), as compared with 2 in the placebo group (8%) (P<0.001). The number of immune epidermal cells increased significantly and the number of immune dermal cells decreased significantly with imiquimod as compared with placebo. Imiquimod reduced pruritus and pain at 20 weeks (P=0.008 and P=0.004, respectively) and at 12 months (P=0.04 and P=0.02, respectively). The lesion progressed to invasion (to a depth of <1 mm) in 3 of 49 patients (6%) followed for 12 months (2 in the placebo group and 1 in the imiquimod group). Nine patients, all treated with imiquimod, had a complete response at 20 weeks and remained free from disease at 12 months. CONCLUSIONS Imiquimod is effective in the treatment of vulvar intraepithelial neoplasia. (Current Controlled Trials number, ISRCTN11290871 [controlled-trials.com].).


The Lancet | 2001

Cytological regression and clearance of high-risk human papillomavirus in women with an abnormal cervical smear.

Mariëlle Ae Nobbenhuis; Theo J.M. Helmerhorst; Adriaan J. C. van den Brule; Lawrence Rozendaal; Feja J. Voorhorst; P. Dick Bezemer; René H.M. Verheijen; Chris J. L. M. Meijer

We studied the natural course of high-risk human papillomavirus (HPV) infection and cytological regression in women referred for colposcopy because of abnormal cervical smears. We found that high-risk HPV clearance preceded regression of cervical lesions by an average of 3 months. The cumulative 1-year rate of cytological regression was similar in women with mild and moderate dyskaryotic cervical smears. Thus, retesting of high-risk HPV after 6 months in women with mild to moderate dyskaryosis predicts cytological regression.


British Journal of Cancer | 2001

Addition of high-risk HPV testing improves the current guidelines on follow-up after treatment for cervical intraepithelial neoplasia

Mariëlle Ae Nobbenhuis; Chris J. L. M. Meijer; A. J. C. Van Den Brule; Lawrence Rozendaal; Feja J. Voorhorst; Elle K.J. Risse; René H.M. Verheijen; Theo J.M. Helmerhorst

We assessed a possible role for high-risk human papillomavirus (HPV) testing in the policy after treatment for cervical intraepithelial neoplasia (CIN) 2 or 3 (moderate to severe dysplasia). According to the Dutch guidelines follow-up after treatment consists of cervical cytology at 6, 12 and 24 months. Colposcopy is only performed in case of abnormal cervical cytology. In this observational study 184 women treated for CIN 2 or 3 were prospectively monitored by cervical cytology and high-risk HPV testing 3, 6, 9, 12 and 24 months after treatment. Post-treatment CIN 2/3 was present in 29 women (15.8%). A positive high-risk HPV test 6 months after treatment was more predictive for post-treatment CIN 2/3 than abnormal cervical cytology (sensitivity 90% and 62% respectively, with similar specificity). At 6 months the negative predictive value of a high-risk HPV negative, normal smear, was 99%. Largely overlapping, partly different groups of women with post-treatment CIN 2/3 were identified by HPV testing and cervical cytology. Based on these results we advocate to include high-risk HPV testing in monitoring women initially treated for CIN 2/3. In case of a high-risk HPV positive test or abnormal cervical cytology, colposcopy is indicated. All women should be tested at 6 and 24 months after treatment and only referred to the population-based cervical cancer screening programme when the tests are negative on both visits.


British Journal of Cancer | 1994

Differences in MHC and TAP-1 expression in cervical cancer lymph node metastases as compared with the primary tumours.

F. V. Cromme; P. F. J. Van Bommel; J. M. M. Walboomers; Maarten P.W. Gallee; P. L. Stern; Peter Kenemans; Theo J.M. Helmerhorst; M. J. Stukart; Chris J. L. M. Meijer

In previous studies we have shown down-regulation of class I major histocompatibility complex (MHC) expression in a significant proportion of primary cervical carcinomas, which was found to be strongly correlated with loss of expression of the transporter associated with antigen presentation (TAP). By contrast, class II MHC expression was frequently up-regulated on neoplastic keratinocytes in these malignancies. In order to investigate whether these changes are associated with biological behaviour of the tumours, 20 cervical carcinomas were analyzed for MHC (HLA-A, HLA-B/C, HLA-DR) and TAP-1 expression in the primary tumours and in lymph node metastases by immunohistochemistry. The results showed a significant increase in the prevalence of HLA-A and HLA-B/C down-regulation in metastasised neoplastic cells as compared with the primary tumour (P = 0.01). In all cases this was accompanied by loss of TAP-1 expression. Up-regulated HLA-DR expression was found exclusively in primary tumours and was absent in the corresponding metastases (P = 0.002). These data are consistent with the hypothesis that loss of TAP-1 and the consequent down-regulation of class I MHC expression provides a selective advantage for neoplastic cervical cells during metastasis. Furthermore, the lack of class II MHC expression in metastasised cells either reflects a different local lymphokine production or indicates that these cells may have escaped CD4+ cytotoxic T-lymphocyte (CTL)-mediated killing.


International Journal of Cancer | 2007

Human papillomavirus testing on self-sampled cervicovaginal brushes: An effective alternative to protect nonresponders in cervical screening programs

Aagje G. Bais; Folkert J. van Kemenade; Johannes Berkhof; René H.M. Verheijen; Peter J.F. Snijders; Feja J. Voorhorst; Milena Babović; Marjolein van Ballegooijen; Theo J.M. Helmerhorst; Chris J. L. M. Meijer

Women not attending cervical screening programs are at increased risk of cervical cancer. We investigated in these nonresponders to what extent offering self‐sampling devices for cervicovaginal brushes for high‐risk human papillomavirus (hrHPV) testing would induce participation and, if so, what the yield of precursor (i.e. CIN2 or worse) lesions following self‐sampling would be. In addition, we assessed screening history of participants and costs per detected high‐grade CIN2 or worse (“CIN2+”) lesion in comparison to the regular program in the Netherlands. Nonresponders received a device for hrHPV testing (self‐sampling group, n = 2,546) or an extra recall for conventional cytology (control group, n = 284). The percentage of self‐sampling responders were compared with responders in the recall group. hrHPV positive self‐sampling responders were invited for cytology and colposcopy. CIN2+ yield and costs per detected CIN2+ were evaluated. Active response was higher in the self‐sampling than in the control group (34.2 vs. 17.6%; p < 0.001). hrHPV positive self‐sampling responders were less likely to have a prior screening history than screening participants (p < 0.001), indicating that they are regular nonresponders. hrHPV prevalence was similar (8.0 vs. 6.8%; p = 0.11), but CIN2+ yield was higher in self‐sampling responders compared to screening participants (1.67 vs. 0.97%; OR = 2.93, 95% CI 1.48–5.80; p = 0.0013). Costs per CIN2+ lesion detected via self‐sampling were in the same range as those calculated for conventional cytological screening (€8,836 vs. €7,599). Offering self‐sampling for hrHPV testing in nonresponders is an attractive adjunct to effectively increase population coverage of screening without the adverse effect of markedly increased costs per detected CIN2+ lesion.


Journal of Clinical Pathology | 2005

A shift to a peripheral Th2-type cytokine pattern during the carcinogenesis of cervical cancer becomes manifest in CIN III lesions.

Aagje G. Bais; Ilse Beckmann; Jan Lindemans; Patricia C. Ewing; Chris J. L. M. Meijer; Peter J.F. Snijders; Theo J.M. Helmerhorst

Background: A shifted balance between T helper 1 (Th1)-type and Th2-type cytokines has been hypothesised in cervical dysplasia Aims: To evaluate possible deregulation of the cytokine network by estimating the expression of peripheral cytokines in different stages of cervical disease and in relation to the presence or absence of high risk human papillomavirus (HR-HPV). Methods: Twenty one HR-HPV positive women with high grade cervical intraepithelial neoplasia (CIN II–III) and 12 patients with invasive cervical carcinoma formed the study groups. Two control groups consisted of 10 HR-HPV positive and 11 HR-HPV negative women without CIN. Differences in leucocyte subgroups were evaluated by a differential leucocyte count. Plasma concentrations of tumour necrosis factor α (TNFα), TNFα receptors TNFRI and TNFRII, interferon γ (IFNγ), interleukin 2 (IL-2), IL-12, IL-4, and IL-10 were determined by enzyme linked immunosorbent assays. Results: Leucocyte counts in patients with CIN III and carcinoma were significantly higher than in controls. Plasma IFNγ concentrations were significantly lower in patients with CIN III and carcinoma than in women with CIN II or controls. Plasma concentrations of IL-12, IL-2, IL-4, and TNFα did not differ significantly between groups, but significantly lower plasma concentrations of TNFRII were found in CIN III and carcinoma compared with CIN II. IL-10 was detected with increased frequency in the plasma of patients with CIN III and carcinoma. Conclusions: These results indicate that a shift to a Th2-type cytokine pattern during the carcinogenesis of cervical cancer occurs in women with CIN III lesions.


The Journal of Pathology | 2008

Association between dense CADM1 promoter methylation and reduced protein expression in high-grade CIN and cervical SCC†

René Overmeer; Florianne E. Henken; Peter J.F. Snijders; Debbie Claassen-Kramer; Johannes Berkhof; Theo J.M. Helmerhorst; Daniëlle A.M. Heideman; Saskia M. Wilting; Yoshinori Murakami; Akihiko Ito; Chris J. L. M. Meijer; Renske D.M. Steenbergen

We previously showed that silencing of TSLC1, recently renamed CADM1, is functionally involved in high‐risk HPV‐mediated cervical carcinogenesis. CADM1 silencing often results from promoter methylation. Here, we determined the extent of CADM1 promoter methylation in cervical (pre)malignant lesions and its relation to anchorage‐independent growth and gene silencing to select a CADM1‐based methylation marker for identification of women at risk of cervical cancer. Methylation‐specific PCRs targeting three regions within the CADM1 promoter were performed on high‐risk HPV‐containing cell lines, PBMCs, normal cervical smears, and (pre)malignant lesions. CADM1 protein expression in cervical tissues was analysed by immunohistochemistry. All statistical tests were two‐sided. Density of methylation was associated with the degree of anchorage‐independent growth and CADM1 gene silencing in vitro. In cervical squamous lesions, methylation frequency and density increased with severity of disease. Dense methylation (defined as ≥ 2 methylated regions) increased from 5% in normal cervical samples to 30% in CIN3 lesions and 83% in squamous cell carcinomas (SCCs) and was significantly associated with decreased CADM1 protein expression (p < 0.00005). The frequency of dense methylation was significantly higher in ≥ CIN3 compared with ≤ CIN1 (p = 0.005), as well as in SCCs compared with adenocarcinomas (83% versus 23%; p = 0.002). Detection of dense CADM1 promoter methylation will contribute to the assembly of a valuable marker panel for the triage of high‐risk HPV‐positive women at risk of ≥ CIN3. Copyright


Clinical Cancer Research | 2005

Detection of Human Papillomavirus (HPV) 16-Specific CD4+ T-cell Immunity in Patients with Persistent HPV16-Induced Vulvar Intraepithelial Neoplasia in Relation to Clinical Impact of Imiquimod Treatment

Mariette I.E. van Poelgeest; Manon van Seters; Marc van Beurden; Kitty M. C. Kwappenberg; Claudia Heijmans-Antonissen; Jan W. Drijfhout; Cornelis J. M. Melief; Gemma G. Kenter; Theo J.M. Helmerhorst; Rienk Offringa; Sjoerd H. van der Burg

Purpose: Topical application of the immune response modifier imiquimod is an alternative approach for the treatment of human papillomavirus (HPV)–positive vulvar intraepithelial neoplasia (VIN) and aims at the immunologic eradication of HPV-infected cells. We have charted HPV16-specific immunity in 29 patients with high-grade VIN and examined its role in the clinical effect of imiquimod treatment. Experimental Design: The magnitude and cytokine polarization of the HPV16 E2-, E6-, and E7-specific CD4+ T-cell response was charted in 20 of 29 patients by proliferation and cytokine bead array. The relation between HPV16-specific type 1 T-cell immunity and imiquimod treatment was examined in a group of 17 of 29 patients. Results: HPV16-specific proliferative responses were found in 11 of the 20 patients. In eight of these patients, T-cell reactivity was associated with IFNγ production. Fifteen of the women treated with imiquimod were HPV16+, of whom eight displayed HPV16 E2- and E6-specific T-cell immunity before treatment. Imiquimod neither enhanced nor induced such immunity in any of the subjects. Objective clinical responses (complete remission or >75% regression) were observed in 11 of the 15 patients. Of these 11 responders, eight patients displayed HPV16-specific type 1 CD4+ T-cell immunity, whereas three lacked reactivity. Notably, the four patients without an objective clinical response also lacked HPV16-specific type 1 T-cell immunity. Conclusions: HPV16-specific IFNγ-associated CD4+ T-cell immunity, although not essential for imiquimod-induced regression of VIN lesions, may increase the likelihood of a strong clinical response (P = 0.03).


Journal of The Society for Gynecologic Investigation | 2003

Distinct functional differences of human progesterone receptors A and B on gene expression and growth regulation in two endometrial carcinoma cell lines

Ellen Smid-Koopman; Leen J. Blok; Liesbeth C. M. Kühne; Curt W. Burger; Theo J.M. Helmerhorst; Albert O. Brinkmann; Frans J. Huikeshoven

Objective: To study the functional differences between the two progesterone receptor isoforms (hPRA and hPRB) in human endometrial cancer, two new endometrial carcinoma cell lines were created—one expressing hPRA and one expressing hPRB. Methods: A well-differentiated, hPR-negative Ishikawa cell line was stably transfected with either hPRA or hPRB cDNA. Transfected cells were selected, and two cell lines expressing approximately equal amounts of receptor were isolated—one expressing hPRA (PRA-14) and one expressing hPRB (PRB-59). Results: Cell growth experiments revealed a growth-inhibitory response to progestins (MPA and R5020) in the PRB-59 cells but not in the PRA-14 cells. Differences in expression of genes targeted by the two isoforms were studied using a cDNA expression array technique. A different se to genes appeared to be progesterone regulated in the PRA-14 cells than in the PRB-59 cells. None of the genes were regulated by both hPRA and hPRB. Insulin-like growth factor binding protein 3 expression was studied in more detail as an example of a gene regulated in PRB-59 cells but not in PRA-14 cells. Conclusion: We established a new model to study functional differences between the two hPR isoforms in human endometrial carcinoma cells. This model revealed distinctive differences in target gene regulation between the two hPR isoforms. Moreover, antiproliferative actions of progesterone on human endometrial cancer cells could be observed only in the PRB-expressing cell line.


Cancer Research | 2009

Chromosomal Signatures of a Subset of High-Grade Premalignant Cervical Lesions Closely Resemble Invasive Carcinomas

Saskia M. Wilting; Renske D.M. Steenbergen; Marianne Tijssen; Wessel N. van Wieringen; Theo J.M. Helmerhorst; Folkert J. van Kemenade; Maaike C.G. Bleeker; Mark A. van de Wiel; Beatriz Carvalho; Gerrit A. Meijer; Bauke Ylstra; Chris J. L. M. Meijer; Peter J.F. Snijders

Cervical cancer develops from precancerous high-grade cervical intraepithelial neoplasia (CIN) harboring a transforming infection with high-risk human papillomavirus, which is characterized by p16(INK4a) overexpression. Once such a lesion has developed, progression toward an invasive squamous cell carcinoma (SCC) may take one or more decades, underlining the heterogeneity of these lesions in terms of duration of existence and progression risk. We performed array-based comparative genomic hybridization (array CGH) on 46 p16(INK4a) immunopositive CIN2/3 lesions to determine whether this heterogeneity is reflected in their chromosomal profiles. Chromosomal profiles of CIN2/3 lesions were related to those of invasive cervical SCC and promoter methylation of CADM1, a tumor suppressor gene known to be functionally involved in the tumorigenic phenotype of cervical cancer cells. Frequent alterations found in CIN2/3 lesions included gains located at chromosome 1, 3, 7, and 20 and losses located at 4, 11, 16, 17, and 19. Unsupervised hierarchical clustering identified two subsets of CIN2/3 lesions, chromosomal profiles of one of which closely resembled invasive SCCs. Gains of 1, 3q, and 20 were characteristic for CIN2/3 lesions with chromosomal signatures resembling carcinomas. In addition, dense promoter methylation of the CADM1 gene was significantly more frequent in these CIN2/3 lesions (P = 0.004). No chromosomal alterations were detected in six CIN1 lesions, five of which were completely p16(INK4a) immunonegative. These findings suggest that biomarkers associated with gains at chromosomes 1, 3q, and 20 are potential hallmarks of advanced p16(INK4a)-positive CIN2/3 lesions with a high short-term risk of progression.

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Peter J.F. Snijders

VU University Medical Center

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Leen J. Blok

Erasmus University Rotterdam

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Ilse Beckmann

Erasmus University Rotterdam

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Marc van Beurden

Netherlands Cancer Institute

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Patricia C. Ewing

Erasmus University Medical Center

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Aagje G. Bais

Erasmus University Rotterdam

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