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Biomedical subjects

R H Verheijen

Publications and source records attributed to R H Verheijen.

At least 19 recordsLinked to original sources
PubMed2003

Type II secretory phospholipase A2 binds to ischemic flip-flopped cardiomyocytes and subsequently induces cell death.

Type II secretory phospholipase A2 (sPLA2) is a cardiovascular risk factor. We recently found depositions of sPLA2 in the necrotic center of infarcted human myocardium and normally appearing cardiomyocytes adjacent to the border zone. The consequences of binding of sPLA2 to ischemic cardiomyocytes are not known. To explore a potential effect of sPLA2 on ischemic cardiomyocytes at a cellular level we used an in vitro model. The cardiomyocyte cell line H9c2 or adult cardiomyocytes were isolated from rabbits that were incubated with sPLA2 in the presence of metabolic inhibitors to mimic ischemia-reperfusion conditions. Cell viability was established with the use of annexin V and propidium iodide or 7-aminoactinomycin D. Metabolic inhibition induced an increase of the number of flip-flopped cells, including a population that did not stain with propidium iodide and that was caspase-3 negative. sPLA2 bound to the flip-flopped cells, including those negative for caspase-3. sPLA2 binding induced cell death in these latter cells. In addition, sPLA2 potentiated the binding of C-reactive protein (CRP) to these cells. We conclude that by binding to flip-flopped cardiomyocytes, including those that are caspase-3 negative and presumably reversibly injured, sPLA2 may induce cell death and tag these cells with CRP.

Animals↗
PubMed2001

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

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.

Adult↗
PubMed2001

Influence of the route of administration on targeting of ovarian cancer with the chimeric monoclonal antibody MOv18: i.v. vs. i.p.

MOv18 antibody binds the membrane folate receptor highly expressed on ovarian carcinoma cells. Since ovarian cancer is mainly limited to the peritoneal cavity, locoregional delivery of therapeutics can be an option. The same patient was injected i.v. and i.p. with c-MOv18 IgG labeled with different radionuclides. To study the kinetics of c-MOv18, patients were divided into 2 groups. Fifteen patients received c-MOv18 labeled with (131)I, (125)I and (123)I (for imaging). Seven patients were operated 2 days, 7 patients 6 days and 1 patient 3 days post-injection. Radioactivity was determined in blood, ascites and biopsies of tumor and of several normal tissues. No adverse events occurred. No anti-MOv18 responses were observed. The area under the blood activity vs. time curve (AUC) was significantly lower after i.p. injection for 2 and 6 days post-injection (p = 0.01 and p = 0.02, respectively). At 2 days post-injection, a significant difference in tumor uptake was found in favor of the i.v. route of administration (4.9% and 2.4%ID/kg for i.v. and i.p., respectively; p < 0.0001). Uptake in solid tumor tissue in ovarian cancer patients operated 6 days post-injection was not significantly different (p = 0.79) for both routes (3.8% and 3.9%ID/kg for i.v. and i.p., respectively). In conclusion, no advantage could be demonstrated for the i.p. route with respect to tumor uptake. The i.p. route could be advantageous with respect to bone marrow toxicity since the AUC was significantly lower for the i.p. route. However, within 2 days post-injection, the blood clearance followed the same pattern for both routes.

Adult↗
PubMed2001

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

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.

Adult↗
PubMed2001

Dysplastic changes in prophylactically removed Fallopian tubes of women predisposed to developing ovarian cancer.

The aim of this study was to investigate the occurrence of (pre)neoplastic lesions in overtly normal Fallopian tubes from women predisposed to developing ovarian carcinoma. The presence of (pre)neoplastic lesions was scored in histological specimens from 12 women with a genetically determined predisposition for ovarian cancer, of whom seven tested positive for a germline BRCA1 mutation. A control group included 13 women. Immunohistochemistry was used to determine the expression of p21, p27, p53, cyclin A, cyclin D1, bcl-2, Ki67, HER-2/neu, and the oestrogen and progesterone receptors. Loss of heterozygosity (LOH) analysis on the BRCA1 locus was also assessed on dysplastic tissue by PCR studies. Of the 12 women with a predisposition for ovarian cancer, six showed dysplasia, including one case of severe dysplasia. Five harboured hyperplastic lesions and in one woman no histological aberrations were found in the Fallopian tube. No hyperplastic, dysplastic or neoplastic lesions were detected in the Fallopian tubes of control subjects. In the cases studied, morphologically normal tubal epithelium contained a higher proportion of Ki67-expressing cells (p=0.005) and lower fractions of cells expressing p21 (p<0.0001) and p27 (p=0.006) than in the control group. Even higher fractions of proliferating cells were found in dysplastic areas (p=0.07) and accumulation of p53 was observed in the severely dysplastic lesion. Expression patterns of other proteins studied, including the hormone receptors, were similar in cases and controls. One subject, a germline BRCA1 mutation carrier, showed loss of the wild-type BRCA1 allele in the severely dysplastic lesion. In conclusion, the Fallopian tubes of women predisposed to developing ovarian cancer frequently harbour dysplastic changes, accompanied by changes in cell-cycle and apoptosis-related proteins, indicating an increased risk of developing tubal cancer.

Adult↗
PubMed2001

Survival analysis in familial ovarian cancer, a case control study.

OBJECTIVE: familial ovarian cancer patients have been found to differ from sporadic cases, clinically as well as in the molecular make-up of the tumour. Here, a case control study is performed to analyse potential differences in survival. STUDY DESIGN: 31 families with a strong history of ovarian and/or breast cancer presenting to a family cancer clinic 44 ovarian cancer patients were included. Each patient was matched for age and stage with controls from a cancer registry. Survival rates and the effect of several prognostic factors were analysed. RESULTS: median survival in the study group differed significantly from controls. A survival benefit for familial cases was maintained up to 5 years after diagnosis. Long-term survival was equally poor in both groups. CONCLUSION: the difference in survival between familial ovarian cancer cases and matched controls may reflect differences in biological behaviour. This may have important implications for the management and prevention of familial ovarian cancer.

BRCA1 Protein↗
PubMed2001

Comparative genomic hybridization of microdissected familial ovarian carcinoma: two deleted regions on chromosome 15q not previously identified in sporadic ovarian carcinoma.

The vast majority of familial ovarian cancers harbor a germline mutation in either the breast cancer gene BRCA1 or BRCA2 tumor suppressor genes. However, mutations of these genes in sporadic ovarian cancer are rare. This suggests that in contrast to hereditary disease, BRCA1 and BRCA2 are not commonly involved in sporadic ovarian cancer and may indicate that there are two distinct pathways for the development of ovarian cancer. To characterize further differences between hereditary and sporadic cancers, the comparative genomic hybridization technique was employed to analyze changes in copy number of genetic material in a panel of 36 microdissected hereditary ovarian cancers. Gains at 8q23-qter (18 of 36, 5 cases with high-level amplifications), 3q26.3-qter (18 of 36, 2 cases with high-level amplifications), 11q22 (11 of 36) and 2q31-32 (8 of 36) were most frequent. Losses most frequently occurred (in decreasing order of frequency) on 8p21-pter (23 of 36), 16q22-pter (19 of 36), 22q13 (19 of 36), 9q31-33 (16 of 36), 12q24 (16 of 36), 15q11-15 (16 of 36), 17p12-13 (14 of 36), Xp21-22 (14 of 36), 20q13 (13 of 36), 15q24-25 (12 of 36), and 18q21 (12 of 36). Comparison with the literature revealed that the majority of these genetic alterations are also common in sporadic ovarian cancer. Deletions of 15q11-15, 15q24-25, 8p21-ter, 22q13, 12q24 and gains at 11q22, 13q22, and 17q23-25, however, appear to be specific to hereditary ovarian cancer. Aberrations at 15q11-15 and 15q24-25 have not yet been described in familial ovarian cancer. In these regions, important tumor suppressor genes, including the hRAD51 gene, are located. These and other yet unknown suppressor genes may be involved in a specific carcinogenic pathway for familial ovarian cancer and may explain the distinct clinical presentation and behavior of familial ovarian cancer.

BRCA2 Protein↗
PubMed2001

Pharmacologic study of paclitaxel administered with or without the cytoprotective agent amifostine, and given as a single agent or in combination with epirubicin and cisplatin in patients with advanced solid tumors.

The main purpose of this study was to investigate whether the coadministration of amifostine alters the pharmacokinetic behavior of paclitaxel. Eight patients were included in the study: six received paclitaxel in combination with epirubicin and cisplatin, and two received paclitaxel as a single agent. Doses of paclitaxel in these protocols were 135, 150, 175, and 200 mg/m(2) and two patients were treated at each dose level. Pharmacokinetic sampling for paclitaxel analysis was performed in each patient during two consecutive cycles, one with and one without amifostine (750 mg/m(2) as a 15-minute intravenous infusion 30 minutes before paclitaxel administration). At each dose level, the pharmacokinetic data of paclitaxel were compared per patient for a cycle without amifostine versus a cycle with amifostine. Amifostine did not seem to interact pharmacokinetically with paclitaxel, given either alone or in combination chemotherapy. This is in line with the clinical findings that amifostine has no negative effects on the antitumor activity of various antineoplastic agents. Also, amifostine may reduce toxic effects of combination chemotherapy regimens that include paclitaxel.

Amifostine↗
PubMed2001

Prospective multicenter evaluation of the morphometric D-score for prediction of the outcome of endometrial hyperplasias.

Prospective multicenter evaluation of the WHO classification and the morphometric D-score to predict endometrial hyperplasia cancer progression. In 132 endometrial hyperplasias WHO classification was performed by two experienced gynecologic pathologists. The D-score was assessed blindly by technicians in a routine diagnostic setting. Development of endometrial carcinoma during a 1-10-year follow-up was used as the end point. Eleven of 132 patients (8%), 10 of 61 (16%) atypical hyperplasias, and 1 of 71 (1%) nonatypical hyperplasias developed cancer. Twenty-six curettings had a D-score < or = 0 ("unfavorable" or endometrial intraepithelial neoplasia) of which 10 (38%) developed cancer. None of the 86 cases with a D-score > 1 ("favorable") and one of the 20 (5%) cases with 0 < D-score < or = 1 ("uncertain") developed cancer. Sensitivity of the D-score was 100%, specificity 82%, the positive and negative predictive values were 38% and 100%, respectively. These values are similar to those in three prior retrospective D-score studies but higher than the WHO values (which are 91%, 58%, 16%, and 99%, respectively). The D-score in endometrial hyperplasias is a more sensitive and specific marker for cancer prediction than the WHO classification, can be assessed in a routine clinical setting on standard hematoxylin and eosin sections (15-30 minutes per case), and is highly reproducible and cost-effective (U.S. $50 per case).

Adult↗
PubMed2000

Human papillomavirus type 16 E6/E7-specific cytotoxic T lymphocytes in women with cervical neoplasia.

Infection with oncogenic human papillomavirus (HPV) types is associated with the development of cervical neoplasia (CIN). The E6 and E7 oncoproteins are constitutively expressed in these lesions and are therefore putative targets for the immune response against HPV. The relation between HPV 16-specific memory cytotoxic T-cell precursor (mCTLp) activity to both oncoproteins and the natural course of cervical dysplasia was analyzed in 38 patients participating in a nonintervention cohort study of women with CIN and 11 HPV 16-positive cervical carcinoma patients. In a cross-sectional study at the end of follow-up prior to biopsy, 8 of 20 patients with a persistent HPV 16 infection had specific mCTLp against at least one of the two oncoproteins. By contrast, no specific mCTLp activity was detected in 11 HPV-negative patients or in 7 patients who had cleared an HPV 16 infection at the end of follow-up. However, 5 of 11 cervical carcinoma patients showed mCTLp activity against the E7 protein only. This study demonstrates that HPV 16 oncogene-specific mCTLp are present in women with HPV 16-positive CIN prior to any intervention. Since HPV-specific mCTLp were detected predominantly in women with high-grade lesions or invasive cervical carcinoma and not in women who cleared the virus, the role of naturally occurring mCTLp in the protection against HPV-associated cervical neoplasia remains to be established.

Cohort Studies↗
PubMed2000

Distribution of 37 mucosotropic HPV types in women with cytologically normal cervical smears: the age-related patterns for high-risk and low-risk types.

Before guidelines can be set for the use of high-risk human papillomavirus (HR HPV) testing in cervical cancer screening and vaccine preparation, age-related prevalence of HR HPV types in cytologically normal smears has to be known. Therefore, in a cross-sectional study the prevalence of 37 different HPV genotypes and putatively unidentified HPV types was determined in 3,305 cytologically normal cervical smears from the general female population (15-69 years of age) using an HPV general primer GP5+/bioGP6+ mediated PCR assay. Subsequently, HPV-positive cervical smears were typed for 19 HR and 18 low-risk (LR) HPVs with an enzyme immunoassay using HPV type-specific oligoprobes in cocktails and individually, respectively. Overall, -HR and -LR HPV prevalences appeared to be of 4.6%, 3.3%, and 1.0%, respectively. Twenty-six different HPV types were detected in the 152 HPV-positive samples, the most prevalent types being HPV 16, 31, and 18. With regard to age, a peak prevalence of 19.6% for all HPVs was found in women 25-29 years of age, which declined to a mean of 4.3% in women over 30 years. With regard cytologically normal cervical smears (n = 3, 011) of women participating in the population-based screening program in the Netherlands (30 to 60 years), all HR HPVs showed decreased occurrence with increasing age, whereas the prevalence of LR HPV types remained constant. We suggest that screening for abnormal cytology implies screening for HR HPV infections and the subsequent treatment results in a decline of HR HPV prevalence in contrast to LR HPV prevalence during the years of screening.

Adolescent↗
PubMed2000

Molecular evidence linking primary cancer of the fallopian tube to BRCA1 germline mutations.

OBJECTIVES: BRCA1 and BRCA2 germline mutations increase the risk of ovarian and breast cancer. Fallopian tube cancer has occasionally been observed in breast-ovarian cancer families. At our family cancer clinic we recently encountered two cases of Fallopian tube cancer within two families harboring a BRCA1 germline mutation. To study the relationship between Fallopian tube cancer and BRCA1 mutations, a histopathological reevaluation and molecular analysis were performed. METHODS: Medical and histopathological reports of the Fallopian tube cancer cases as well as archival tissue blocks were retrieved. The histopathological diagnoses were reevaluated. We investigated whether patients with Fallopian tube cancer had been carriers of a BRCA germline mutation. In addition we investigated whether loss of the wild-type allele had occurred in the tumor. RESULTS: In 2 of 23 families with a known BRCA1 mutation from our family cancer clinic, a case of Fallopian tube cancer was reported. Histological reevaluation confirmed the diagnosis of Fallopian tube cancer in both cases. In one case Fallopian tube cancer may have been part of a multifocal primary malignancy. In both patients the presence of a BRCA1 mutation was confirmed in the germline. Furthermore, we showed loss of the wild-type BRCA1 allele in both tumors. CONCLUSIONS: These findings provide the first molecular evidence that Fallopian tube cancer may be due to germline mutations in BRCA1. This may have important consequences for the preferred method of prophylactic oophorectomy in BRCA1 mutation carriers.

Adult↗
PubMed2000

Ovarian cancer in female-to-male transsexuals: report of two cases.

BACKGROUND: Ovarium cancer is the fifth most common cause of cancer-related death in women and is the most common fatal gynecologic malignancy. So far, ovarium carcinoma has not been reported to have occurred in female-to-male transsexuals. OBJECTIVE AND METHOD: We report on two such cases. Long-term exposure to increased levels of endogenous and exogenous androgens is hypothesized to constitute an additional risk factor in transsexuals as it has been associated with ovarian epithelian cancer. CONCLUSION: Simultaneous salpingo-oophorectomy should be performed in any female-to-male transsexual undergoing hysterectomy in the course of gender-confirming therapy.

Androgens↗
PubMed2000

Sentinel node detection in cervical cancer.

BACKGROUND: For superficial tumors such as melanoma, breast, and vulvar cancer, sentinel node detection prevents unnecessary extensive lymph node dissections. Sentinel node detection has not yet proved feasible in tumors, such as cervical cancer, that drain to deep pelvic lymph nodes. TECHNIQUE: We injected technetium-99m colloidal albumin around the tumor allowing preoperative lymphscintigraphy and intraoperative gamma probe detection of sentinel nodes. For visual detection, blue dye was injected at the start of surgery. EXPERIENCE: In six of 10 eligible women who had Wertheim-Meigs operations for cervical cancer stage Ib, one or more sentinel nodes could be detected by scintigraphy. Intraoperative gamma probe detection was successful in eight of ten women, whereas visual detection found sentinel nodes in only four. They were found as far as the common iliac level. One woman had positive lymph nodes, of which one was a sentinel node. CONCLUSION: Identification of sentinel nodes using radionuclide is possible in women with cervical cancer and potentially identifies women in whom lymph node dissection can be avoided.

Adult↗
PubMed2000

Analysis of human papillomavirus type 16 E6 variants in relation to p53 codon 72 polymorphism genotypes in cervical carcinogenesis.

This study aimed to assess the role of specific human papillomavirus type 16 (HPV-16) variants, in combination with p53 codon 72 polymorphism genotypes, in cervical carcinogenesis. An initial sequence analysis of HPV-16 long control, E6 and E7 regions of 53 well-defined cervical samples containing HPV-16 revealed that a T to G transition at nucleotide position 350 within the E6 open reading frame was the most common variation, the frequency of which seemed to decrease with increasing severity of the lesion. Therefore, a total of 246 cervical samples of residents of The Netherlands was specifically analysed for HPV-16 350G/T variants and/or p53 codon 72 genotypes. These comprised HPV-negative normal cervical scrapes (n=40), normal cervical scrapes containing HPV-16 (n=46), scrapes containing HPV-16 from women with abnormal cervical cytology participating in a non-intervention follow-up study without (n=38) and with (n=51) a histologically proven cervical intraepithelial neoplasia (CIN) III lesion at the end of the study, and cervical squamous cell carcinomas (n=71). Neither specific HPV-16 350G/T variants nor specific p53 genotypes were associated with a higher risk of developing CIN III or cervical cancer. However, HPV-16 350T variants were significantly over-represented in p53 Arg homozygous women with cervical cancer. This suggests that, in p53 Arg/Arg women, infection with HPV-16 350T variants confers a higher risk of cervical cancer.

Base Sequence↗
PubMed2000

Sentinel lymph node procedure is highly accurate in squamous cell carcinoma of the vulva.

PURPOSE: To determine the diagnostic accuracy of the sentinel lymph node procedure in patients with squamous cell carcinoma of the vulva and to investigate whether step sectioning and immunohistochemistry of sentinel lymph nodes increase the sensitivity for detection of metastases. PATIENTS AND METHODS: Between July 1996 and July 1999, 59 patients with primary vulvar cancer were entered onto a two-center prospective study. All patients underwent sentinel lymph node procedure with the combined technique (preoperative lymphoscintigraphy with technetium-99m-labeled nanocolloid and intraoperative blue dye). Radical excision of the primary tumor with uni- or bilateral inguinofemoral lymphadenectomy was performed subsequently. Sentinel lymph nodes and lymphadenectomy specimens were sent for histopathologic examination separately. Sentinel lymph nodes, negative at the time of routine pathologic examination, were re-examined with step sectioning and immunohistochemistry. RESULTS: In 59 patients, 107 inguinofemoral lymphadenectomies were performed (11 unilateral and 48 bilateral). All sentinel lymph nodes, as observed on preoperative lymphoscintigram, were identified successfully intraoperatively. Routine histopathologic examination showed lymph node metastases in 27 groins, all of which were detected by the sentinel lymph node procedure. The negative predictive value for a negative sentinel lymph node was 100% (97.5% confidence interval [CI], 95% to 100%). Step sectioning and immunohistochemistry showed four additional metastases in 102 sentinel lymph nodes (4%; 95% CI, 1% to 9%) that were negative at the time of routine histopathologic examination. CONCLUSION: Sentinel lymph node procedure with the combined technique is highly accurate in predicting the inguinofemoral lymph node status in patients with early-stage vulvar cancer. Future trials should focus on the safe clinical implementation of the sentinel lymph node procedure in these patients. Step sectioning and immunohistochemistry slightly increase the sensitivity of detecting metastases in sentinel lymph nodes and should be included in these trials.

Adult↗