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S Parkkinen

Publications and source records attributed to S Parkkinen.

29 records · Page 2Linked to original sources

Tumorigenicity of primary mouse fibroblasts transformed by bovine papillomavirus type 1.

Cell lines transformed by bovine papillomavirus type 1 DNA were established from transfected primary fibroblast cultures of C57BL/6 mice. Southern blot analysis revealed that most of the viral DNA in the cells was in episomal oligomeric form. These cell lines were tested for tumorigenicity in nude mice in comparison to properties associated with malignant transformation including growth in low-serum medium, focus formation in agar, and resistance to natural killer cells. Two of the 5 cell lines were highly tumorigenic, producing spindle cell sarcomas in all animals. Metastatic spreading to local lymph nodes was also observed. The same cell lines also showed anchorage-independent growth in agar, but no correlation was observed between natural killer cell resistance and tumorigenicity. Viral transcripts were detected in two nontumorigenic and in two tumorigenic cell lines.

Animals↗

Evolution of human papillomavirus infections in the uterine cervix during a long-term prospective follow-up.

A series of 513 women presented with cervical human papillomavirus (HPV) infections (with or without cervical intraepithelial neoplasia; CIN) have been prospectively followed up since 1981 (mean 25.6 months), at 6-month intervals, by colposcopy with PAP smears and/or punch biopsies. The latter were analyzed by light microscopy, as well as immunohistochemically for HPV structural proteins. HPV DNA typing was accomplished by Southern blot, spot, and in situ hybridization techniques using the DNA probes for HPV 6, 11, 16, 18 and 31. Of the 513 lesions, 24.8% regressed, 59.8% persisted, and 14.1% progressed, 11.9% having been coned due to progression to carcinoma in situ (CIS). So far, 1.1% of lesions have recurred after such a treatment. The natural history was significantly associated with the grade of CIN (HPV-NCIN versus HPV-CIN, p less than 0.01). The progression rate was highest (33.3%) and regression lowest (5.6%) in HPV 16 lesions. All the recurrent lesions disclosed HPV 16 DNA, this type being found most frequently in the severest lesions (CIN III). Depending on the hybridization technique used, changes in HPV type were found in 11-17% of the lesions during the follow-up. Noteworthy is the discovery of all the HPV types also in biopsies with no signs of HPV infection on light microscopy, suggesting a latent HPV infection in these 'regressor' lesions. The results confirm that cervical HPV infections show a natural history comparable to that of classical CIN. Although the high-risk character of HPV 16 (and HPV 18) was clearly established, the inherent potential for progression (25.6%) of the HPV 6/11 lesions should not be neglected in therapeutic considerations.

Adolescent↗

Human papillomavirus (HPV) infections involved in the neoplastic process of the uterine cervix as established by prospective follow-up of 513 women for two years.

A total of 513 women with cervical HPV infections have been followed-up since 1981 (mean 25.6 months) to establish the biological potential of HPV in cervical carcinogenesis. On each attendance, the patients were subjected to colposcopy accompanied by Papanicolaou (PAP) smears and/or punch biopsies. The latter were analysed for HPV particles on TEM, for the cytopathic changes of HPV, as well as for HPV structural proteins. The local immunocompetent cell (ICC) infiltrates are enumerated using ANAE-technique to define B-, MPS- and T cells, and monoclonal antibodies for T cell subsets, NK and K cells and Langerhans cells. HPV DNA typing was accomplished by Southern blot and spot hybridization using the DNA probes for HPV 6, 11, 16 and 18. Antibody titres for HSV were measured, and Chlamydia trachomatis isolations completed in cervical swabs. No correlation with the clinical course, e.g. regression (RE), persistence (PE), progression (PR) or recurrence (RC) of the HPV lesions could be established for the following factors; expression of HPV antigens, presence of HPV particles on TEM, Chlamydia in cervical swabs, the levels of HSV antibodies, and the levels of the ICCs. The OKT4+/OKT8+ cell ratio, however, was inversely correlated with PR, being most markedly reduced in recurrent lesions. Of the 513 lesions, 24.8% regressed, 59.8% remained persistent, and 14.1% progressed, 11.9% having been coned due to progression into CIS. So far, 1.1% of lesions have recurred after such a treatment. The progression rate was highest (45.5%) in HPV 16 lesions, followed by that (27.3%) in HPV 18 lesions, as contrasted to 0% and 13.3% for HPV 6 and 11, respectively. The results clearly confirm that cervical HPV infections are capable of progressing into CIS and thus show a natural history equivalent to that of classical CIN. The inherent potential of HPV 16 and HPV 18 lesions for clinical progression was clearly established, supporting the concept on HPV 16 and HPV 18 as the high risk HPV types in cervical carcinogenesis.

Adolescent↗

Detection of human papillomavirus DNA by the nucleic acid sandwich hybridization method from cervical scraping.

Cervical scrapes collected from 100 consecutive patients participating in a prospective follow-up study for cervical human papillomavirus (HPV) infections were tested for the presence of HPV 11 DNA by the nucleic acid sandwich hybridization method, which allows testing the specimens in a crude form. Part of each specimen was processed through phenol extraction and DNA purification to a dot blot hybridization assay. The dot blots were serially hybridized with HPV 6, 11, 16, and 18 probes as well as with an Alu-repeat probe to estimate the number of cells in the specimen. In PAP smears, HPV-infection was suspected in 63 patients whereas in 37 patients the smear was negative. In the first group, the dot blot assay revealed three cases of HPV 11, two of HPV 16, and one of HPV 18 infection. In the second group with normal PAP smear, one additional HPV 18 infection was found. The sandwich hybridization assay detected 5 HPV 11 infections, including the three mentioned above. All HPV DNA-positive samples contained at least 1.6 X 10(6) cells. Since we considered this a prerequisite for successful diagnosis, only 25 specimens in the first group and 15 in the second were adequate specimens. Thus the HPV-DNA detection rate was 32% (8/25) in the first group and 1/15 in the second. This study demonstrates that sandwich hybridization, detecting 1-3 X 10(5) HPV 11 molecules is a reliable diagnostic method. Cervical scrape is a valuable alternative to punch biopsy, but the number of cells collected is critical for the outcome of the assay.

Cervix Uteri↗

Human papillomavirus (HPV) DNA sequences demonstrated by in situ DNA hybridization in serial paraffin-embedded cervical biopsies.

An in situ DNA hybridization technique was used to identify various types of Human papillomavirus (HPV) in paraffin sections of serial punch biopsies taken from 64 patients having colposcopy because of abnormal smears. There women were in fact 64 consecutive patients out of 505 attending our clinic (at 6-month intervals) since 1981 for HPV infections. HPV 6 DNA sequences were found in 20%, HPV 11 in 17%, HPV 16 in 8% and HPV 18 in 5% of the 64 biopsies analysed with this method so far. More than 60% of HPV 6-positive lesions belong to HPV-NCIN (HPV lesion without concomitant CIN) or HPV-CIN I categories, as contrasted with HPV 16-positive lesions, 80% of which belong to HPV-CIN II and III categories. None of the HPV 16- or HPV 18-infected lesions regressed, as contrasted with 23% and 45% in those infected with HPV 6 and HPV 11, respectively (P less than 0.01). The rate of progression (38.4% and 45.5%, respectively) was markedly lower in HPV 6- and HPV 11 lesions as compared with that (80%) of HPV 16 lesions. The present results while supporting the concept on HPV 16 and HPV 18 as the high risk HPV types in cervical carcinogenesis also emphasize the applicability of the in situ DNA hybridization as a powerful tool in analysis of the specific HPV DNA sequences in routinely progressed biopsies of these lesions.

Carcinoma in Situ↗

Coexistent chlamydial infections related to natural history of human papillomavirus lesions in uterine cervix.

To assess the role of Chlamydia trachomatis in the development of cervical intraepithelial neoplasia (CIN) and to evaluate possible synergism between chlamydiae and human papillomavirus (HPV) in this process, 418 women who had been prospectively followed up for cervical HPV infections at our clinic since 1981 were tested for chlamydiae. At each visit the patients were examined by colposcopy, and other investigations, such as Papanicolaou (Pap) smears, punch biopsies, urethral, and cervical swabs, were undertaken as indicated. In biopsy specimens the cytopathic changes of HPV, concomitant CIN, and the local immunocompetent cell infiltrates were analysed. The latter were measured and further identified using an alpha naphthyl acetate esterase (ANAE) technique to define B cells, macrophages, and T cells and using monoclonal antibodies to define T cell subsets, NK (natural killer cells), and Langerhans cells. Chlamydial isolation (4.1% in the cervix, and 3.6% in the urethra) did not positively correlate with the degree of cytological atypia in PAP smears or with the degree of CIN lesions associated with HPV. Chlamydial cervicitis did not affect the ANAE definable cell composition of the immunocompetent cell infiltrates in HPV lesions, or that of the immunocompetent cell subsets, including the ratios of T helper to T suppressor cells and the numbers of NK cells. Chlamydial infection did not alter the natural history of HPV lesions, of which 30% regressed, 53% persisted, and 17% progressed during follow up. The present results do not provide evidence to substantiate the hypothesis that chlamydiae and HPV might act synergistically in cervical carcinogenesis, or the view that C trachomatis may be a major aetiological agent of CIN lesions. Chlamydiae and HPV are covariables of sexual behaviour, and their concomitant appearance in sexually promiscuous women is best explained by this fact. As we do not have more direct evidence for the oncogenic potential of C trachomatis (as we have of HPV), it seems reasonable to consider that this agent is not a major cause of CIN, but rather a sexually transmitted agent commonly found in women with CIN because of their promiscuous sexual behaviour.

Adolescent↗

Electron microscopy in assessment of the biological behavior of human papillomavirus infections in the uterine cervix.

To asses the natural history of human papillomavirus (HPV) infections in uterine cervix, currently implicated in etiology of cervical cancer, a prospective follow-up study has been conducted for 418 women at our clinic since 1981. The present communication summarized the current follow-up data of these patients, with special emphasis on detection of the virus in cervical punch biopsies, as correlated with other characteristics pertinent to the clinical behavior of cervical HPV infections. On each attendance, the patients are subjected to colposcopy accompanied either by Papanicolaou (PAP) smears or punch biopsies. The latter are analyzed for the cytopathic changes of HPV, for concomitant cervical intraepithelial neoplasia (CIN), for HPV structural proteins with IP-PAP technique as well as on transmission electron microscopy (TEM) for the presence of HPV particles. The local immunocompetent cell (ICC) infiltrates are analyzed using ANAE technique to define B cells, MPS cells and T cells and monoclonal antibodies (McAb) for T cell subsets, NK (natural killer) cells and Langerhans cells. HPV particles were disclosed with equal frequency (approx. 65%) in all three types of HPV lesions. Surprisingly, HPV particles were present in 70% of the biopsies derived from the regressed lesions (e. g. in those without histological evidence of HPV lesions), suggesting a possibility of a latent HPV infection. Presence of viral particles did not bear any direct correlations with the expression of HPV antigens, intensity or cellular composition of the ICC infiltrate, defined by ANAE or using McAb. Presence of HPV particles was not a major prognostic determinant, whereas the clinical course was most significantly influenced by the grade of HPV-associated CIN, to which regression was inversely and progression directly related. The results clearly confirm that cervical HPV infections are capable of progressing into carcinoma in situ and thus present with a natural history equivalent to that of classical CIN.

Female↗

Human papillomavirus (HPV) type as an important determinant of the natural history of HPV infections in uterine cervix.

The present report summarizes our current observations on the natural history of cervical HPV (Human papillomavirus) infections, based on data from 418 women prospectively followed-up in our clinic for a mean of 20 +/- 15 (M +/- SD) months. On each attendance at the clinic (at 6-month intervals), the patients are subjected to colposcopy accompanied by PAP smears and/or punch biopsy, both being analysed for the cytopathic changes of HPV, and for concomitant CIN (cervical intraepithelial neoplasia). In the biopsies, the expression of HPV structural proteins was assessed using an indirect immunoperoxidase (IP-PAP) technique. HPV typing was accomplished by spot hybridization with the DNA probes for HPV 6, 11, 16 and 18. During the follow-up, 24% of the HPV lesions regressed, 55% remained persistent, and 21% progressed, 10.6% having been coned due to progression into CIS. The clinical progression was significantly associated with the grade of HPV-associated CIN. On DNA hybridization, HPV 6 was found in 8%, HPV 11 in 36%, HPV 16 in 11% and HPV 18 in 8% of the 103 lesions typed for HPV DNA so far. HPV-CIN lesions were more frequently than HPV-NCIN associated with HPV 16 and HPV 18, as was the expression of HPV structural proteins. The progression rate was highest (45.5%) in HPV 16 lesions, followed by that (27.3%) in HPV 18 lesions, as contrasted to 0% and 13.3% for HPV 6 and 11, respectively. The natural history of cervical HPV lesions seems to be identical with that of classical CIN lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Natural history of cervical human papillomavirus (HPV) infections based on prospective follow-up.

To assess the natural history of human papillomavirus (HPV) lesions in the uterine cervix, a prospective follow-up of untreated lesions has been conducted since late 1981. The present report summarizes the data on 343 women with cervical HPV lesions currently followed-up for a mean of 18.7 (SD 15.2) months by colposcopy and PAP smears (group B) or by additional punch biopsy (group A). Initially these two groups were classified on the first PAP smears, presenting with HPV-induced cytopathic changes, and either with (group A) or without (group B) concomitant changes suggestive of cervical intraepithelial neoplasia (CIN). The clinical course of the HPV lesions could not be predicted adequately from the findings of the first PAP smears, as evidenced by the higher progression rate (15.4%) in the 214 women initially classified in group B, compared with 11.6% in the 129 women classified in group A. Furthermore, the number progressing to carcinoma in situ requiring conization was equal (seven patients) in the two groups. This necessitated a more flexible approach to follow-up, permitting transfer of patients between groups, which resulted in a final allocation of 261 women to group A, and 82 to group B. To date, 25% of the total of 343 HPV lesions have regressed, 61% have persisted, and 14% have progressed. Of the latter, a total of 14 (4.1%) have been coned due to progression to carcinoma in situ. The rate of regression seems to be inversely related, and progression directly related, to the degree of HPV-associated CIN.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Cervical smears in assessment of the natural history of human papillomavirus infections in prospectively followed women.

The value of cervical (Papanicolaou) smears in monitoring the natural history of cervical human papillomavirus (HPV) infections was assessed in a series of 513 women prospectively followed since 1981. On each clinic visit, the patients were subjected to colposcopy accompanied by cervical smears and/or punch biopsies. The latter were analyzed by light microscopy for concomitant cervical intraepithelial neoplasia (CIN) and by transmission electron microscopy (TEM) for HPV particles as well as for HPV structural proteins. The stromal immunocompetent cell (ICC) infiltrates were phenotypically characterized using monoclonal antibodies for T-cell subsets, NK and K cells and Langerhans cells. HPV DNA typing was accomplished by Southern blot, spot and in situ hybridization using probes for HPV 6, 11, 16, 18 and 31. Lesions showing only changes consistent with HPV infection (HPV-NCIN) were associated with less severe atypia in cervical smears than were lesions with coexistent CIN (HPV-CIN). Normal smears were observed, however, in 24.7% of the cases with HPV-NCIN lesions, in 11.5% of cases with HPV-CIN I lesions but only exceptionally in cases with HPV-CIN II and III lesions (2.2% and 3.3%). The percentages of the different ICC phenotypes did not correlate with the atypia in cervical smears, but there was a shift towards the lower values of the T-helper/T-suppressor (OKT4+/OKT8+) cell ratio in parallel with increasing atypia. The possibility of latent HPV infection was suggested by the detection of viral particles, HPV antigens and HPV DNA in lesions shedding normal cells in the smears. The high-risk HPV types 16 and 18 were associated with the highest frequency of severely atypical cells; in the majority of cases, the low-risk types HPV 6 and 11 presented with less severe atypia. The first cervical smear seems to be of value as a predictor of the natural history of HPV lesions, as indicated by the fact that regression was inversely and progression directly related to initial cellular atypia. The present results confirm the intimate association between HPV infections and CIN. Although the biologic potential of the HPV infections seems to be dependent on multiple factors, routine cervical smears, because of their potential value in monitoring the natural history of this infection, should constitute an important means in the prospective follow-up of these patients.

Adult↗