Search PubMed⌕ Search

Biomedical subjects

C J Meijer

Publications and source records attributed to C J Meijer.

At least 127 records · Page 7Linked to original sources
PubMed1999

Screening for genital human papillomavirus: results from an international validation study on human papillomavirus sampling techniques.

The objective of this study was to determine the validity of human papillomavirus (HPV) detection using exfoliated cervical cells compared with cervical biopsy specimens in women with normal cervix and to assess whether HPV detection rates using exfoliated cells is dependent on the number and order in which cervical scrapes are taken. Women undergoing hysterectomy for reasons other than cervical cancer were recruited in three hospitals in countries with varying risks of cervical cancer. After informed consent and at the time of surgery, three consecutive cervical scrapes were taken as well as four biopsy specimens, one in each of the quadrants around the cervical os. In this study, 331 women were recruited and provided 992 cell samples and 1324 biopsy samples. All scrapes and a sample of biopsy specimens (n = 103) were tested by polymerase chain reaction enzyme immunoassay using a general primer (GP5+/ bio6+). Type-specific tests were performed for 14 HPV types at the subpicogram level in one test and individually. Positive samples were verified using Southern blot hybridization. The prevalence of HPV DNA was 6.3% in cervical cells. Of 19 HPV positive samples in the scrapes, 17 were confirmed in the biopsy specimens. The agreement, as measured by the Kappa statistic, was 0.90 (P < 0.0001). The concordance in detecting HPV infection between scrapes and biopsy specimens was 97.5%, and the concordance in categorizing the samples as negatives was 94.4%. These values were unchanged when the order in which scrapes were taken was compared. Among women without cervical cancer, HPV DNA detection rates do not vary if exfoliated cells or random biopsy specimens are taken as the primary testing specimen. Screening programs based on highly sensitive HPV DNA detection technology in cell scrapes should expect a minimal underdetection.

Biopsy↗
PubMed1999

Immune responses against human papillomavirus (HPV) type 16 virus-like particles in a cohort study of women with cervical intraepithelial neoplasia. I. Differential T-helper and IgG responses in relation to HPV infection and disease outcome.

T-helper (Th) cell-dependent IL-2 production and plasma IgG responses to virus-like particles consisting of the human papillomavirus type 16 (HPV-16) major capsid protein L1 (L1-VLP) were determined in patients with cytological evidence of cervical intraepithelial neoplasia (CIN) participating in a non-intervention prospective cohort study. IgG responses were associated with HPV-16 persistence and high-grade CIN lesions, while high frequencies of Th responses were observed in patients with both virus clearance and virus persistence, irrespective of CIN grade. The IgG response was found in conjunction with an IL-2 response to L1-VLP in 87% of the patients. Recognition of the HPV-16 L1 Th epitope (amino acids 311-335) was found to be more closely associated than recognition of L1-VLP as a whole to HPV exposure and CIN development. Among the HPV-16+ patients included in this study, those showing a Th response to amino acids 311-335 were more likely to carry the HLA DRB1*11/DQB1*0301 haplotype, while those showing an IgG response to L1-VLP were more likely to carry DRB1*0101/DQB1*0501. However, neither cell-mediated nor humoral immune responses against HPV-16 L1 appear to be sufficient for the natural control of HPV infection and CIN development.

Adult↗
PubMed1999

Immune responses against human papillomavirus (HPV) type 16 virus-like particles in a cohort study of women with cervical intraepithelial neoplasia. II. Systemic but not local IgA responses correlate with clearance of HPV-16.

To investigate whether there is an association between local or systemic IgG and IgA responses against human papillomavirus (HPV) type 16 virus-like particles (VLP) containing L1 and L2 and the possible influence of these responses on clearance of HPV-16 and its associated lesions, cervical mucus samples from 125 patients and plasma samples from 100 patients, all participating in a non-intervention cohort study of women with abnormal cytology, were analysed. The results show that local IgG and IgA HPV-16 VLP-specific antibodies do not correlate with virus clearance. However, systemic IgG responses were more frequently detected in patients with a persistent infection (11/24) compared with patients with cleared HPV-16 infections (3/28, P = 0.006). Furthermore, the ultimate development of high-grade lesions was associated with systemic VLP-specific IgG reactivity (P = 0.026). By contrast, systemic IgA responses were correlated with virus clearance (7/28 clearance compared with 1/24 persistence patients, P = 0.06). This correlation was statistically significant when only those clearance patients who tested HPV-16 DNA-positive at more than one visit were included in the analysis (5/11 compared with 1/24, P = 0.007). As these systemic IgA responses were not accompanied by local IgA responses, the systemic IgA responses in HPV-16 clearance patients are suggested to be a by-product of a successful cellular immune response induced at the local lymph nodes, mediated by cytokines.

Adolescent↗
PubMed1999

Determination of Chlamydia trachomatis prevalence in an asymptomatic screening population: performances of the LCx and COBAS Amplicor tests with urine specimens.

This study determined the performances of the LCx (Abbott) and COBAS Amplicor (Roche) tests with urine specimens for the detection of Chlamydia trachomatis in an asymptomatic screening population. Randomly selected women and men (age range, 15 to 40 years) registered in 20 general practices in Amsterdam, The Netherlands, were invited to participate in this study. Urine specimens (n = 2, 906; 1,138 specimens from men and 1,717 specimens from women) were tested for C. trachomatis by the COBAS Amplicor (Roche) and LCx (Abbott) tests. Samples which were positive by only one assay were subjected to discrepant analyses by a third assay (in-house plasmid PCR). By the LCx assay C. trachomatis DNA was detected in urine specimens from 46 of 1,717 women and 29 of 1,138 men, while the COBAS Amplicor detected C. trachomatis DNA in 52 and 35 specimens, respectively. When comparing the LCx and COBAS Amplicor tests, 32 test results (20 for women and 12 for men) were discrepant. After discrepant analyses the following sensitivities, specificities, and positive predictive values were found for the LCx and COBAS Amplicor tests: 78.6 versus 98.8%, 99.7 versus 99.9%, and 88.0 versus 95.4%, respectively. No prominent differences were found between men and women with regard to the test performances. After discrepant analyses the overall prevalences of C. trachomatis in women and men were 3.0 and 2.8%, respectively. For both women and men the prevalence in the younger age groups was higher than that in the older age groups. In conclusion, the COBAS Amplicor tests shows better diagnostic characteristics than the LCx assay for the detection of C. trachomatis in urine specimens from an asymptomatic screening population. In this asymptomatic population the overall prevalence of C. trachomatis was 2.9%.

Adolescent↗
PubMed1999

Mailed, home-obtained urine specimens: a reliable screening approach for detecting asymptomatic Chlamydia trachomatis infections.

The use of mailed, home-obtained urine specimens could facilitate screening programs for the detection of asymptomatic Chlamydia trachomatis infections. Since transport time could have an adverse effect on the sensitivity of C. trachomatis detection by PCR, the influence of DNA degradation on amplification was monitored over the course of 1 week. Therefore, urine specimens were aliquoted on the day of collection or arrival. Two groups of urine specimens were investigated. Group I contains first-void C. trachomatis-positive and -negative urine samples. DNA degradation was monitored in group I samples for 7 days at room temperature (RT) and at 4 degrees C by amplifying different lengths of the human beta-globin gene and the C. trachomatis plasmid target. DNA degradation was observed only for the larger human beta-globin fragments at days 5 to 7 at RT. In contrast, at 4 degrees C all targets could be amplified. Urine specimens were also frozen and thawed before aliquoting to mimic freezing during transport. This resulted in a lower sensitivity for the detection of C. trachomatis after thawing and 3 to 4 days at RT. In addition, mailed, home-obtained C. trachomatis-positive urine specimens (group II) were analyzed for 7 days after arrival by two commercially available C. trachomatis detection systems (PCR and ligase chain reaction [LCR]). The C. trachomatis plasmid target in mailed, home-obtained urine specimens could be amplified by both PCR and LCR after 1 week of storage and/or transport at RT. In conclusion, our findings indicate that mailed, home-obtained urine specimens are suitable for the sensitive detection of asymptomatic C. trachomatis infections by amplification methods, even if the transport time is up to 1 week at RT. These findings support the feasibility and validity of screening programs based on mailed, home-obtained urine specimens. Larger studies should be initiated to confirm our results.

Base Sequence↗
PubMed1999

Monitoring of epstein-barr virus DNA load in peripheral blood by quantitative competitive PCR.

A competitive quantitative PCR (Q-PCR) assay combined with simple silica-based DNA extraction was developed for monitoring of Epstein-Barr virus (EBV) DNA load in unfractionated peripheral blood. The Q-PCR is based on competitive coamplification of a highly conserved 213-bp region of the EBNA-1 open reading frame with an internal standard (IS), added in a known concentration. The IS has the same amplicon length and base composition as the wild-type (WT) EBNA-1 amplicon but differs in 23 internally randomized bases. Competitive coamplification yields two PCR products that are quantified by enzyme immunoassay or by electrochemiluminescence detection, with probes specific for the 23 differing internal nucleotides. The Q-PCR has a sensitivity of 10 copies of either WT or IS plasmid DNA. The Q-PCR was validated by quantification of known amounts of plasmid containing the WT EBNA-1 target. Furthermore, we determined EBV genome copy numbers in different cell lines. For EBV quantification in clinical samples, DNA was isolated from lysed whole blood by silica-affinity purification. Forty-six percent of healthy donor peripheral blood samples were positive by Q-PCR. In most of these samples, viral load was less than 2,000 EBV copies/ml of blood. In peripheral blood samples from two AIDS-related non-Hodgkin's lymphoma patients, elevated EBV loads (up to 120,000 copies/ml) were observed, which decreased upon therapy. In Burkitt's lymphoma patients, up to 4,592,000 EBV genome copies/ml of blood were detected. In conclusion, the EBNA-1-based Q-PCR assay provides a reproducible, accurate, and easy method for studying the relationship between EBV load and clinical parameters.

Burkitt Lymphoma↗
PubMed1999

A cytotoxic phenotype does not predict clinical outcome in anaplastic large cell lymphomas.

AIM: To investigate whether anaplastic large cell lymphomas (ALCL) expressing cytotoxic proteins have a relatively worse clinical outcome compared with ALCL lacking a cytotoxic phenotype. METHODS: 59 primary cases of ALCL originating from different sites were investigated by immunohistochemistry for the presence of the cytotoxic proteins T cell intracytoplasmic antigen (TIA-1) and granzyme B in the neoplastic cells. Since site of origin and expression of anaplastic lymphoma kinase (ALK) strongly influence prognosis, the presence of a cytotoxic phenotype was also investigated in relation to the primary site of origin (lymph node, gut, or skin) and ALK expression. The prognostic value was investigated by analysis of overall and relapse-free survival time, including Cox regression analysis. RESULTS: 39 of 59 ALCL (66%) appeared to have a cytotoxic phenotype as shown by expression of TIA-1 or granzyme B or both in the neoplastic cells. The presence of a cytotoxic phenotype did not have any influence on prognosis. Even when the survival data were corrected for site of origin and stage at presentation or were analysed separately for ALK positive and negative cases, no prognostic influence of a cytotoxic phenotype was observed. CONCLUSIONS: In primary biopsies of patients with ALCL, the presence of a cytotoxic phenotype is not related to clinical outcome of the disease.

Adult↗
PubMed1999

Immunohistochemical differentiation between primary adenocarcinomas of the ovary and ovarian metastases of colonic and breast origin. Comparison between a statistical and an intuitive approach.

AIM: To discriminate between adenocarcinomas that are primary to the ovary and metastatic to the ovary, especially of colonic and breast origin, by immunohistochemistry, using stepwise discriminant analysis or a decision tree. METHODS: 312 routinely processed, formalin fixed tissue specimens were used. The tumours were divided into a learning set (n = 159), composed of primary tumours of ovary, breast, and colon, and a test set, comprising 134 metastases from these sites and an additional 19 primary ovarian carcinomas. The immunohistochemical panel was composed of antibodies against cytokeratin 7 (CK7) and 20 (CK20), CA125, vimentin, carcinoembryonic antigen (CEA), gross cystic disease fluid protein-15 (GCDFP-15), and the oestrogen receptor (ER). The staining results of the tumours were expressed as the product of the staining intensity and the percentage of positive tumour cells. Analyses were first performed on the learning set and then evaluated on the test set. RESULTS: Although the immunostaining patterns showed a considerable overlap between the three types of adenocarcinoma, the breast carcinomas were typically positive for GCDFP-15 and often for ER, and negative for vimentin. Ovarian carcinomas were always positive for CK7 and to a lesser extent for CA125. Colonic carcinomas showed prominent positivity for CEA and CK20, while no staining was seen for ER and vimentin. In discriminant analysis, six antibodies (alpha CK7, alpha CK20, alpha CA125, alpha CEA, alpha ER, and alpha GCDFP-15) appeared to be necessary for optimal classification: 89% of the learning set and 82% of the test set were classified correctly. In the decision tree, only four antibodies (alpha CK7, alpha CEA, alpha ER, and alpha GCDFP-15) were used to obtain a correct classification score of 89% for the learning set and 84% for the test set. CONCLUSIONS: Using a semiquantitative assessment of the immunostaining results by a restricted panel of six antibodies with stepwise discriminant analysis, 80-90% of the adenocarcinomas of colon, breast, and ovary can be correctly classified. Discriminant analysis is computer aided and therefore an easy method and for each case a probability value of the classification result is obtained. The intuitive decision tree method provides a slightly better result, requires only four antibodies, and offers a more practical method for the surgical pathologist.

Adenocarcinoma↗
PubMed1999

Reliable high risk HPV DNA testing by polymerase chain reaction: an intermethod and intramethod comparison.

BACKGROUND: The development of a reproducible, sensitive, and standardised human papillomavirus (HPV) polymerase chain reaction (PCR) test is required to implement HPV testing in cervical cancer screening programmes and for triaging women with mild to moderate dysplasia. AIMS: To determine the intermethod agreement between different GP5+/6+ and MY09/11 PCR based protocols for the detection and typing of high risk (HR) HPV DNA in cervical smears and to assess the intramethod reproducibility of the GP5+/6+ PCR enzyme immunoassay (EIA) for HR-HPV detection. METHODS: For the intermethod comparison, crude aliquots of 20 well characterised cervical smears comprising five HPV negative samples, and six and nine samples containing single and multiple HPV infections, respectively, were coded and sent from reference laboratory (A) to three other laboratories. One of these (laboratory B) used the GP5+/6+ PCR-EIA and was provided with standard protocols. Another laboratory (C) used GP5+/6+ PCR combined with sequence analysis and type specific PCR, whereas two laboratories (D and E) used MY09/11 PCR followed by restriction fragment length polymorphism (RFLP) analysis for the detection and typing of HR-HPV. The intramethod agreement of GP5+/6+ PCR-EIA was analysed in a subsequent study with four other laboratories (F to I) on crude aliquots of 50 well characterised cervical smears, consisting of 32 HR-HPV positive and 18 HPV negative samples. Standardised protocols, primers, and probes were also provided by the reference laboratory for HR-HPV detection. RESULTS: In the intermethod comparison, pairwise agreement of the different laboratories with reference laboratory A for the detection of HR-HPV varied between 75% and 100% (kappa values: 0.5 to 1). Typing data revealed a broader range in pairwise agreement rates between 32% and 100%. The highest agreement was found between laboratories A and B using standardised protocols and validated reagents. In the intramethod evaluation, pairwise comparison of the laboratories F to I with reference laboratory A revealed excellent agreement rates from 92% to 100% (kappa values: 0.88 to 1.0) with an overall sensitivity of 97.5% (195/200) and specificity of 99.5% (199/200). CONCLUSIONS: The detection of HR-HPV as a group is highly reproducible with GP5+/6+ PCR-EIA provided that standardised protocols and validated reagents are used.

Cervix Uteri↗
PubMed1999

Expression of Epstein-Barr virus (EBV) transcripts encoding homologues to important human proteins in diverse EBV associated diseases.

AIMS: To examine the expression of Epstein-Barr virus (EBV) transcripts encoding proteins homologous to important human proteins in diverse EBV associated diseases. The proteins were: BHRF1 (homologous to Bcl-2), BDLF2 (homologous to cyclin B1), BARF1 (homologous to intercellular cell adhesion molecule 1 (ICAM-1)), and BCRF1 (viral IL-10 (vIL-10), homologous to human IL-10 (hIL-10)). METHODS: Six cases of oral hairy leukoplakia, seven of Hodgkin's disease, eight of T cell non-Hodgkin's lymphoma, and nine of nasopharyngeal carcinoma were examined at the mRNA level using either the reverse transcriptase polymerase chain reaction (RT-PCR) or nucleic acid sequence based amplification (NASBA). Different primer sets allowed the differentiation by RT-PCR of the latent (Cp/Wp driven) and lytic (Hp driven) transcripts of BHRF1. A specific NASBA reaction was developed for the detection of vIL-10 and BDLF2 transcripts and this was tested initially on cell lines and later on clinical samples. RESULTS: vIL-10 and BDLF2 were expressed almost exclusively in oral hairy leukoplakia, whereas BARF1 transcripts were present in all cases of nasopharyngeal carcinoma, with weak expression in one oral hairy leukoplakia and isolated cases of lymphoid malignancy. Both BHRF1 transcripts were detected across the range of tissues tested, but strong expression of lytic BHRF1 transcripts was seen only in oral hairy leukoplakia. CONCLUSIONS: vIL-10 and BDLF2 transcripts are expressed during productive EBV infection and are unlikely to be important in the pathogenesis of EBV associated malignancies. BARF1 appears to be expressed preferentially during viral latency and is more closely associated with malignant rather than benign epithelial proliferations. The alternative transcripts derived from the BHRF1 open reading frame may have very different roles during latent or productive infection.

Epstein-Barr Virus Infections↗
PubMed1999

Treatment of multifocal primary cutaneous B-cell lymphoma: a clinical follow-up study of 29 patients.

PURPOSE: Although patients with primary cutaneous B-cell lymphoma (CBCL) and localized skin lesions are generally treated with radiotherapy and have an excellent prognosis, the clinical behavior and optimal treatment of CBCL presenting with multifocal skin lesions are less well defined. In this study, we evaluated the clinical behavior of and results of treatment for multifocal CBCL in 29 patients, and we formulated therapeutic guidelines. PATIENTS AND METHODS: The study group included 16 patients with primary cutaneous follicular center-cell lymphoma (PCFCCL), eight with primary cutaneous immunocytoma (PCI), and five with primary cutaneous large B-cell lymphoma presenting on the legs (PCLBCL of the leg). RESULTS: Only one of the 24 patients with multifocal PCFCCL or PCI developed extracutaneous disease, and no patient died from lymphoma (median follow-up, 54 months). In patients with PCFCCL, treatment with either multiagent chemotherapy (nine patients) or radiotherapy directed toward all skin lesions (five patients) proved equally effective in terms of complete remission, relapse, and survival. In contrast, all five patients with PCLBCL of the leg developed extracutaneous disease, and four of the five died from systemic lymphoma, 8 to 36 months (median, 21 months) after diagnosis. CONCLUSION: The results of these preliminary studies suggest that patients with PCFCCL or PCI presenting with multifocal skin lesions have the same excellent prognosis that patients with localized PCFCCL or PCI have and that radiotherapy directed toward all skin lesions is as effective as multiagent chemotherapy. Patients with PCLBCL of the leg have a more unfavorable prognosis, particularly patients presenting with multifocal skin lesions. This last group should always be treated with multiagent chemotherapy.

Adult↗
PubMed1999

Serum antibodies to human papillomavirus 16 proteins in women from Brazil with invasive cervical carcinoma.

Serum samples from 194 cases and 217 controls participating in a case-control study of invasive cervical cancer in Brazil were examined for antibodies to human papillomavirus (HPV) 16 virus-like particles (VLPs) by ELISA. The prevalence of antibody in cases and controls was 47.4 versus 24.4% (P < 0.001). The prevalence was higher in women who had HPV-16 DNA in the genital tract (54.2%) than in those with other HPVs (36.8%) or no HPVs (44.8%), but the differences were not statistically significant. Among cases and controls, HPV-16 VLP antibodies were associated with a greater number of lifetime sexual partners (chi2 for trend, P < 0.001). Among controls, age was inversely associated with HPV-16 VLP seroreactivity (chi2 for trend, P = 0.019). The sera were previously tested for antibodies to HPV-16 E6 and E7 oncoproteins; there was no correlation between antibody titers to HPV-16 E6 or E7 and VLPs. The HPV-16 serological assays were compared as screening tests for invasive cervical cancer. The sensitivity and specificity estimates were 47.4 and 75.6% for HPV-16 VLP serology, 63.4 and 89.9% for either HPV-16 E6 or E7 serology, and 53.6 and 93.6% for high titers of either HPV-16 E6 or E7 or VLP antibodies. The utility of HPV-16 VLP ELISA as a screening test for invasive cervical cancer is limited by a high seroprevalence in women with probable prior exposure to HVP 16 but without disease.

Adult↗
PubMed1998

[Sexually transmitted infection as a cause of anal cancer].

Interviews were carried out with 423 women and 93 men with invasive or in situ anal cancer in Denmark and Sweden in a search for clues to the aetiology of this neoplasm. Patients with rectal adenocarcinoma (n = 534) and persons drawn from the background population (n = 554) served as controls. Multivariate logistic regression analyses confirmed previous observations of a strong association between either male homosexual experience or a history of anogenital warts and the risk for anal cancer. Moreover, hitherto unknown, but strong and consistent associations were observed between measures of high heterosexual activity and the risk for anal cancer among both sexes. Polymerase chain reaction analysis revealed human papilloma-virus DNA in the majority (88%) of anal cancer specimens but in none of 20 examined rectal adenocarcinomas. It is concluded that most anal cancers appear to be caused by sexually transmitted types of human papillomaviruses and, consequently, that anal cancer is a potentially preventable neoplasm.

Adenocarcinoma↗
PubMed1998

VH gene analysis of primary cutaneous B-cell lymphomas: evidence for ongoing somatic hypermutation and isotype switching.

Primary cutaneous B-cell lymphomas are B-cell non-Hodgkin's lymphomas that arise in the skin. The major subtypes discerned are follicle center cell lymphomas, immunocytomas (marginal zone B-cell lymphomas), and large B-cell lymphomas of the leg. In this study, we analyzed the variable heavy chain (VH) genes of 7 of these lymphomas, ie, 4 follicle center cell lymphomas (diffuse large-cell lymphomas) and 3 immunocytomas. We show that all these lymphomas carry heavily mutated VH genes, with no obvious bias in VH gene usage. The low ratios of replacement versus silent mutations observed in the framework regions of 5 of the 7 lymphomas suggest that the structure of the B-cell antigen receptor was preserved, as in normal B cells that are selected for antibody expression. Moreover, evidence for ongoing mutation was obtained in 3 immunocytomas and in one lymphoma of large-cell type. In addition, in 1 immunocytoma, both IgG- and IgA-expressing clones were found, indicative of isotype switching. Our data provide insight into the biology of primary cutaneous B-cell lymphomas and may be of significance for their classification.

Codon↗
PubMed1998

HPV 16 infection and progression of cervical intra-epithelial neoplasia: analysis of HLA polymorphism and HPV 16 E6 sequence variants.

High-risk human papillomavirus (HPV) infection plays an important role in cervical intra-epithelial neoplasia (CIN), but HPV infection alone is not sufficient for progression to cervical cancer. Several lines of evidence suggest that cellular immune surveillance is important in the control of HPV infection and the development of CIN. The presentation to T cells of target viral peptides in the context of HLA molecules is influenced by the genetic polymorphisms of both HPV and HLA and thereby influences the host immune response and clinical outcome of HPV infection. HLA class I and II polymorphism in susceptibility for HPV 16 infection, development and progression of CIN was analyzed in a group of 118 patients participating in a prospective study of women with initial abnormal cytology. Patients were stratified according to HPV status and course of the disease. HLA-B*44 frequency was increased in the small group of patients with a lesion that showed clinical progression during follow-up [OR = 9.0 (4.6-17.5), p = 0.007]. HLA-DRB1*07 frequency was increased among HPV 16-positive patients compared with patients who were negative for all HPV types [OR = 5.9 (3.0-11.3), p = 0.02]. Our results are consistent with the immunogenetic factors associated with disease progression being different from those associated with susceptibility to HPV 16 infection. Sequencing of the HPV 16 E6 and E7 open reading frames of a subset of these patients (n = 40) showed the frequency of HPV 16 variants to be similar to other studies. However, there was no significant correlation between variant incidence and disease progression or viral persistence and no significant correlation with any HLA allele. It appears that multiple HLA types can influence HPV 16-associated cervical dysplasia but the role of HPV 16 variants in disease progression and susceptibility in relation to HLA polymorphism remains unclear.

Adult↗
PubMed1998

Telomerase activity exclusively in cervical carcinomas and a subset of cervical intraepithelial neoplasia grade III lesions: strong association with elevated messenger RNA levels of its catalytic subunit and high-risk human papillomavirus DNA.

In this study, we investigated telomerase activity and human telomerase reverse transcriptase (hTERT) mRNA expression in relation to high-risk human papillomavirus (HPV) DNA presence in the spectrum of cervical premalignant lesions. Reconstruction experiments revealed that telomerase activity determined by the telomeric repeat amplification protocol assay and hTERT mRNA by reverse transcriptase-PCR could be detected in down to 100 and 1 SiHa cervical cancer cells, respectively. Telomeric repeat amplification protocol analysis on cervical tissue specimens revealed that none of the histomorphologically normal cervical samples (n = 8) and cervical intraepithelial neoplasia (CIN) grade I (n = 10) and grade II (n = 8) lesions had detectable telomerase activity. However, telomerase activity was shown in 40% of CIN grade III lesions (n = 15) and 96% of squamous cell carcinomas (n = 24). Despite the fact that hTERT mRNA was found at much higher frequencies, semiquantitative reverse transcriptase-PCR revealed that elevated hTERT mRNA levels were strongly correlated with detectable telomerase activity. Furthermore, telomerase activity and elevated hTERT mRNA levels were only detected in cases that contained high-risk HPV DNA. In contrast, low or undetectable hTERT mRNA levels were demonstrated in both high-risk HPV positive and negative cases. These data indicate that telomerase activity detectable with the assay used and concomitant elevated levels of hTERT mRNA reflect a rather late step in the CIN to squamous cell carcinoma sequence, which follows infection with high-risk HPV.

DNA, Viral↗
PubMed1998

Different risk factor patterns for high-grade and low-grade intraepithelial lesions on the cervix among HPV-positive and HPV-negative young women.

Risk factors for cervical intraepithelial neoplasia have most often been studied in high-grade lesions. Furthermore, in a high proportion of the studies, human papillomavirus (HPV), the most significant risk determinant of cervical neoplasia, was not taken into account when evaluating other risk factors. To compare risk factors for ASCUS (atypical cells of undetermined significance), LSIL (low-grade squamous intraepithelial lesion) and HSIL (high-grade squamous intraepithelial lesion), we conducted a case-control study among 20 to 29 year-old women participating in a prospective cohort study in Copenhagen. It included 131 women with ASCUS, 120 women with LSIL, 79 women with HSIL and 1,000 randomly chosen, cytologically normal, control women. All participants had a personal interview and a gynecological examination including a Pap smear and cervical swabs for HPV DNA detection using general primer-mediated polymerase chain reaction. The most significant risk determinant of all 3 disease categories was the presence of genital HPV DNA. The risk factor pattern was nearly identical for ASCUS and LSIL, but differed significantly from that for HSIL. Stratified analysis by HPV-status showed that, apart from, respectively, smoking and parity among HPV-positive women, and smoking and number of sex partners among HPV-negative women, no additional risk factors were observed for ASCUS and LSIL. In contrast, among HPV-negative women with HSIL, long-term use of oral contraceptives was the most important risk factor. However, our result should be taken with great caution as it is based on very small numbers, and as it is unknown whether the HPV-negative lesions constitute a true entity. Among HPV-positive women, the risk of HSIL was associated with e.g., years of sex life without barrier contraceptive use, early age at first genital warts and smoking. Whether the risk factors that are applicable only to HSIL represent factors related to progression remains unknown.

Adult↗