Human papillomavirus, p16(INK4A), and Ki-67 in relation to clinicopathological variables and survival in primary carcinoma of the vagina.

BACKGROUND: This study aimed to determine human papillomavirus (HPV) status and to investigate p16(INK4A) and Ki-67 expression and their correlation with clinical parameters and survival in women with primary carcinoma of the vagina (PCV). METHODS: The presence of HPV DNA was evaluated by PCR. Genotyping was performed by Luminex in 68 short-term (2 years) and long-term (8 years) PCV survivors. p16(INK4A) and Ki-67 expression was evaluated by immunohistochemistry. RESULTS: Human papillomavirus DNA was detected in 43% of patients, the majority (63%) of whom were HPV16 positive. High p16(INK4A) expression was significantly correlated with low histopathological grade (P=0.004), HPV positivity (P=0.032), and long-term survival (P=0.045). High Ki-67 expression was negatively correlated with histopathological grade (P<0.001) and tumour size (P=0.047). There was an association between HPV positivity and low histopathological grade, but not between HPV positivity and survival. CONCLUSION: High p16(INK4A) expression was associated with long-term survival, but the only independent predictors for survival were tumour size and histopathological grade. Our results indicate that p16(INK4A) and Ki-67 expression might be useful in tumour grading, and that it might be possible to use p16(INK4A) expression as a marker for HPV positivity, but this has to be further elucidated.

Self-sampling of vaginal fluid and high-risk human papillomavirus testing in women aged 50 years or older not attending Papanicolaou smear screening.

OBJECTIVES: To study the value of self-sampling of vaginal fluid at home in combination with high-risk human papillomavirus (HPV) testing in a cohort of older women not attending Papanicolaou (Pap) smear screening. DESIGN: Women (n = 3618), aged 50-65 years, who had not attended screening for at least 6 years were offered self-sampling of vaginal fluid at home (study cohort). The collected material was analysed for the presence of high-risk HPV (using Hybrid capture 2; Hc2). Women with a positive HPV test were referred for colposcopy. These results were compared with the results of Pap smear screening in a corresponding age group of women (controls). The end point of the study was identification of a histological cervical intraepithelial neoplasia stage 2 (CIN2) and above (CIN2+). RESULTS: In all, 39.4% (n = 1426) women participated and 4.6% (n = 66) were high-risk HPV positive. Of the HPV-positive women 56 chose to attend a surgery (84.8%) after a mean time of 2.1 months and ten of these women (17.9%) showed CIN2+, corresponding to 0.70% of all participating women. In the controls, who participated in organised Pap smear screening, the prevalence of CIN2+ was 0.25% (15/6048). The odds ratio for identification of CIN2+ in women aged 50 years or older performing self-sampling and HPV test in comparison with Pap smear was: 2.84 (95% CI 1.14-6.77, P = 0.0174). In older women primary high-risk HPV testing (Hc2) and Pap smear screening showed equal specificity of around 96%. CONCLUSIONS: Self-sampling of vaginal fluid in combination with high-risk HPV testing appears to be an attractive method to improve screening coverage and decrease the prevalence of cervical cancer in women aged 50 years or older.

Short-time repeat high-risk HPV testing by self-sampling for screening of cervical cancer.

BACKGROUND: Testing for high-risk human papillomavirus (HPV) in primary screening for cervical cancer is considered more sensitive, but less specific, in comparison with Pap-smear cytology. Women with persistent HPV infections have a higher risk of developing cervical intraepithelial neoplasia 2+ (CIN2+) lesions. This study was performed to evaluate the gain in specificity for detection of histologically confirmed CIN2+ lesions achieved by short-time repeat testing for high-risk HPV in women aged 30-65 years, with the primary sample for HPV analysis taken by self-sampling. METHODS: A total of 8000 women in Uppsala County, aged 30-65 years, who had not attended organised screening for 6 years or longer, were offered self-sampling of vaginal fluid at home and the samples sent for HPV typing. Of these, 8% (669) were not possible to contact or had performed hysterectomy. Women positive for high-risk HPV in the self-sampling test were invited for a follow-up HPV test and a cervical biopsy on average 3 months after the initial HPV test. RESULTS: In all, 39% (2850/7331) of invited women chose to perform self-sampling of vaginal fluid at home. High-risk HPV infection was found in 6.6% (188) of the women. In all, 89% of the women testing HPV positive performed a follow-up examination, on average 2.7 months, after the first test and 59% of these women were HPV positive in the follow-up test. The prevalence of CIN2+ lesions in women with an initial HPV-positive test was 23% (95% CI 18-30%) and in women with two consecutive HPV-positive tests was 41% (95% CI 31-51%). In women with two positive HPV tests, the prevalence of CIN2+ lesions varied from 49% in women at age 30-39 years to 24% in women at age 50-65 years. Short-time repeat HPV testing increased the specificity for detection of CIN2+ lesions from about 94.2% to 97.8%. The most prevalent HPV types were HPV16 (32%), followed by HPV18/45 (19%) and HPV 33/52/58 (19%). CONCLUSION: The short-time persistence of high-risk HPV infection in this age group was about 60%. Repeat testing for high-risk HPV using self-sampling of vaginal fluid can be used to increase the specificity in the screening for cervical cancer in women aged 30-65 years.

Self-sampling and HPV testing or ordinary Pap-smear in women not regularly attending screening: a randomised study.

BACKGROUND: Most women with cervical cancer have not participated in Pap-smear screening. Self-sampling of vaginal fluid in combination with high-risk HPV testing may be a method to increase the attendance rate. METHODS: A total of 4060 women, 39-60 years old, who had not attended the organised Pap-smear screening for 6 years or more were randomised into two equal groups. A study group was offered to self-sample vaginal fluid (Qvintip) at home and/or recommended to attend the Pap-smear screening. The collected fluid after self-sampling was examined for the presence of high-risk HPV (Hybrid Capture 2 method). Controls were only recommended to attend the Pap-smear screening. The end point was a histological identification of CIN2-3. RESULTS: The participation rate was 39% (771 out of 2000) in the self-sampling group and 9% (188 out of 2060) in the conventional cytology (P<0.001). The number of histological CIN2-3 alterations detected was 0.4% (8 out of 2000) among women offered self-sampling of vaginal fluid and 0.07% (3 out of 4060) in women offered Pap-smears. The odds ratio (OR) for offering self-sampling and HPV testing instead of Pap-smear screening for detection of CIN2-3 was OR=5.42 (95% CI: 1.30-31.8). CONCLUSION: Offering self-sampling of vaginal fluid followed by a high-risk HPV test was considerably more effective for detection of histological CIN2-3 lesions in comparison with offering Pap-test in a midwife reception in women not regularly attending organised screening.

Self-sampling of the vaginal fluid at home combined with high-risk HPV testing.

BACKGROUND: Around 65% of women with cervical carcinoma in Sweden have not attended an organised screening. We therefore investigated the value of using self-sampling at home in combination with a test for high-risk human papilloma virus (HPV) to increase participation. METHODS: A total of 2829 women 30-58 years old, who had not attended the organised screening for > or = 6 years, were recruited. They were offered self-sampling at home (Qvintip) and recommended to send the collected vaginal fluid to a laboratory for analysis of the presence of high-risk HPV (Hybrid Capture 2 method). RESULTS: A total of 39.1% of the women accepted home sampling. These women disclosed a relatively high prevalence of high-risk HPV, which decreased with age, from 11.1% in women 30-39 years old to 2.9% in women > or =50 years . Follow-up disclosed histological cervical intraepithelial neoplasm (CIN) 2-3 lesions in 43.2% of the women with a persistent HPV infection, corresponding to 2.0% of the total number of participating women. The sensitivity of a single smear to detect the histological CIN 2-3 lesions were only 52.6%, even if all abnormal smears (atypical squamous cells of unknown significance (ASCUS)-CIN 3)) were included. CONCLUSION: The use of self-sampling at home in combination with testing for high-risk HPV increases the participation rate of the organised screening and detects almost twice as many women with pre-malignant cell alterations (CIN 2-3) in comparison those with a single cytological smear.

Comparative study of the effect of luminal hypotonicity on mucosal permeability in rat upper gastrointestinal tract.

AIM: To investigate whether the increase in mucosal permeability in the duodenum, induced by luminal hypotonicity, also occurs in the stomach and the jejunum and whether this increase in permeability can be explained by epithelial injury. METHODS: The stomach, duodenum or jejunum of the anaesthetized rat were perfused with a hypotonic solution and effects on mucosal permeability (blood-to-lumen clearance of radioactive probes); luminal alkalinization and net fluid flux were determined in the absence and presence of cyclooxygenase inhibition. RESULTS: The hypotonicity-induced (50 mM NaCl) increase in duodenal mucosal permeability was markedly larger in cyclooxygenase-2-inhibited animals than in controls and associated with a 20% decrease in luminal alkalinization and increased fluid absorption. Perfusion with 50 mM NaCl increased duodenal mucosal permeability to all probes investigated, i.e. (14)C-urea, (14)C-methyl-D-glucose, (51)Cr-EDTA and (14)C-inulin. The percentage increase in permeability was the greatest for inulin and the lowest for urea. Luminal hypotonicity caused superficial villous tip damage in some but not in all duodenal specimens but there was no difference in morphology between controls and cyclooxygenase-2-inhibited animals. Jejunum, but not the stomach, responded to luminal hypotonicity by increasing net fluid absorption, mucosal permeability (greater than sixfold) and the rate of luminal alkalinization (>100%). CONCLUSIONS: The stomach does not respond while the jejunum is more sensitive to hypotonicity-induced increase in mucosal permeability than the duodenum. The hypotonicity-induced increase in duodenal mucosal permeability most probably constitutes a physiological mechanism that entails widening of paracellular pathways, which facilitates the transport of osmolytes into the lumen.

The carcinogenic role of oncogenic HPV and p53 gene mutation in cervical adenocarcinomas.

Thirty tumors were collected from our archive of cervical adenocarcinomas. They were examined with respect to the content of oncogenic HPV and presence of mutations in the p53 gene exons 5 through 8. Furthermore, available clinical information on the cases was reviewed. For the detection of p53 gene and presence of oncogenic HPV, PCR followed by direct sequence analysis of the amplified DNA was employed. Seventeen tumors were identified as HPV-positive, comprising both HPV types 18 and 16. Six cases showed a p53 gene mutation, of which five were of the missence and one of the silent type. No statistical correlation between the occurrence of oncogenic HPV and presence of p53 gene mutation (p = 0.67) was recorded. Among the tumors with p53 gene mutation, three were HPV-positive and three were HPV-negative. The determination of p53 gene mutations was not related to clinical findings such as the stage of the tumor or presence of metastases of the lymph nodes. However, p53 gene mutations were somewhat more prevalent in low differentiated tumors (p < 0.02). The results indicate that oncogenic HPV and p53 gene mutations have independent carcinogenic roles in cervical adenocarcinomas.

High viral loads of human papillomavirus predict risk of invasive cervical carcinoma.

High loads of human papillomavirus (HPV) 16 and HPV 18/45 increase the risk of developing invasive cervical carcinoma, revealing higher risk in percentiles of highest viral loads for HPV 16 (odds ratio (OR) 58.7, 95% confidence interval (CI) 21.9-151.4) compared to HPV 18/45 (OR 3.3, 95% CI 1.5-7.2). Thus, HPV load is a type-dependent risk marker for invasive carcinoma.

Human papillomavirus 16 E6 polymorphisms in cervical lesions from different European populations and their correlation with human leukocyte antigen class II haplotypes.

Infection with high-risk human papillomavirus (HPV) is necessary for the development of a cervical lesion, but only a fraction of precursor lesions progress to cancer. Additional factors, other than HPV type per se, are likely to increase the probability for progression. Intratype genome variations have been reported to be associated with viral persistence and the development of a major cervical disease. We have recently shown that the prevalence of specific HPV16-E6 variants in invasive cervical cancer (ICC) varies between Italian and Swedish women. To extend our initial study we have analyzed E6 variants in cervical lesions from Czech women, ranging from low-grade cervical intraepithelial neoplasia (LCIN) to ICC and scaled up the sample size of our initial study of Swedish and Italian women. In addition, we have correlated the cases of cancers with human leukocyte antigen (HLA) class II haplotypes. In line with our earlier observation, the distribution of specific HPV16-E6 genotypes in CIN and ICC varied in the 3 cohorts. For instance, the HPV16-E6 L83V variant, which has been found to be positively associated with ICC in Swedish women (p = 0.002), was more prevalent in LCIN than in ICC in Italian and Czech women (p = 0.01 and = 0.03, respectively). These data indicate that host genetic factors, such as HLA polymorphism, may determine the potential oncogenicity of the HPV16-E6 L83V variant. Indeed, the DR04-DQ03 haplotype, which is approximately 3-fold more abundant in the normal Swedish population than in those in Italy and the Czech Republic, was found to be positively associated with HPV16-E6 L83V in the 3 cohorts investigated (p = 0.01). This observation may explain why L83V is a risk factor more in Sweden than in the other 2 countries.

Chromogranin A in human neuroendocrine tumors: an immunohistochemical study with region-specific antibodies.

Antibodies to six specific regions of the chromogranin A (CgA) molecule were used to study their immunoreactivity in human neuroendocrine (NE) tumors. Tissue specimens from endocrine pancreatic tumors (n = 14), duodenal carcinoids (n = 2), bronchial carcinoids (n = 5), ileal carcinoids (n = 5) appendix carcinoids (n = 2), medullary thyroid carcinomas (n = 6), parathyroid adenomas (n = 2), and pheochromocytomas (n = 8) were analyzed. The results showed that the NE tumor types expressed varying numbers of CgA fragments. A variation in frequency of the expression of immunoreactive cells was sometimes seen also within the same tumor type. The midportion fragment CgA 176-195 (chromacin) was the only fragment expressed in all tumors. Benign and malignant tumors expressed different patterns, being especially true of insulinomas and pheochromocytomas. These findings suggest that region-specific antibodies to CgA fragments can be used as a diagnostic tool for the characterization of NE tumors.

The significance of p53 codon 72 polymorphism for the development of cervical adenocarcinomas.

Infection with the human papillomavirus is an important co-factor in the development of cervical carcinomas. Accordingly, HPV DNA is recognised in most of these tumours. Polymorphism of the p53 gene, codon 72, is also considered a risk factor in the development of cervical carcinoma. However, this finding is contradicted by several observers. In the present investigation, 111 cases of adenocarcinoma of the cervix collected through the Swedish Cancer Registry and 188 controls (females with normal cytology at organised gynaecological screening) were analysed with regard to p53, codon 72, polymorphism using a PCR- and SSCP-based technique. In the controls, 9% showed pro/pro, 44% pro/arg and 47% arg/arg, whereas in the invasive adenocarcinomas, the corresponding figures were 0%, 29% and 71%, respectively. The difference was statistically significant (P = 0.001). HPV DNA was identified in 86 tumours (HPV 18 in 48, HPV 16 in 31 and HPV of unknown type in 7 cases) and 25 tumours were HPV negative. The p53, codon 72, genotypes observed in HPV-positive and HPV-negative cervical adenocarcinomas were not statistically different (P = 0.690). The results indicate that women homozygotic for arg/arg in codon 72 of the p53 gene are at an increased risk for the development of cervical adenocarcinomas. However, this genetic disposition seems to be unrelated to the HPV infection.

Analysis of intratumoral heterogeneity of chromosome 3p deletions and genetic evidence of polyclonal origin of cervical squamous carcinoma.

Investigation on intratumoral genetic heterogeneity provides an important insight into the roles of genetic alterations in human carcinogenesis and clues to clonal origin of tumors. Intratumoral heterogeneity of genetic changes of cervical cancer has not been described so far. In this study, we analyzed the intratumoral heterogeneity of chromosome 3p deletions and X-chromosome inactivation patterns in multiple microdissected samples from each individual cervical cancer, attempting to understand the roles of 3p deletions in development of cervical cancer and its clonal origin. Totally, 120 normal and lesional samples from 14 cases of fresh cervicalcancers were analyzed. Frequency and patterns of allelic losses of 3p were assessed by polymerase chain reaction (PCR) amplification of 12 microsatellite markers flanking the frequently deleted regions of 3p, followed by Genescan analysis in an ABI 377 DNA sequencer. Loss of heterozygosity was recorded as heterogeneous pattern (LOH present in parts of samples or LOH involving different alleles among different samples) and homogeneous pattern (LOH involving identical alleles in all samples from the tumor). Allelic loss affecting at least one marker was detected in 8 of 14 cases (57%). Allelic losses, both homogeneous and heterogeneous, were frequently detected at FHIT gene region (D3S1300, 40% and 60%; D3S4103, 27.3% and 54.6%), 3p21.3-21.2 (D3S1478, 27.3% and 45.5%), and 3p24.2-22 (D3S1283, 30% and 50%). Seven of eight LOH-positive tumors exhibited homogeneous allelic loss involving at least one of these three 3p loci. Allelic losses were present in the CIN lesions synchronous with invasive lesions positive for LOH. Our findings suggest essential roles of genes on these 3p loci, particularly the FHIT gene in participating in clonal selection and early development of cervical cancer. Most interestingly, with the combination of LOH analysis and X-chromosome inactivation analysis, we provided the first clear genetic evidence of polyclonal origin of cervical invasive cancer in two of eight cases. This finding strongly suggests the importance of field defect (possible human papilloma virus) in cervical carcinogenesis.

p53 codon 72 polymorphism and various human papillomavirus 16 E6 genotypes are risk factors for cervical cancer development.

Risk factors other than human papillomavirus (HPV) infection per se for cervical cancer development have been investigated recently. It was suggested that HPV 16 E6 variants and the p53 codon 72 arginine polymorphism could be progression markers. Indeed, it has been demonstrated that specific E6 variants and p53 arginine were both enriched in cancer. However, especially with regard to the latter, divergent results have been reported. Our aim was thus to investigate whether p53 arginine is important for cervical carcinogenesis by scaling up samples of the two European cohorts, the initial results of which were reported previously. In addition, we have assessed the occurrence of p53 codon 72 arginine, in combination with specific HPV 16 E6 genotypes. We found p53 arginine to be increased in cancer of both cohorts, consistent with our previous concept. Although specific E6 genotypes increased gradually with the severity of the lesion, p53 arginine was enriched in cancer only. Moreover, the frequency of the arginine allele was similar in groups with different E6 genotypes. It is concluded that p53 arginine is a risk factor for cervical cancer but probably acts independently of E6 variants.

The role of human papillomavirus in cervical adenocarcinoma carcinogenesis.

Human papillomavirus (HPV) is considered the single most important co-factor in the development of cervical squamous cell carcinomas. Adenocarcinomas of the cervix are also related to HPV, but the correlation is reported to be less pronounced. In the present study, 131 cervical adenocarcinomas were identified through the Swedish Cancer Registry, examined morphologically and then analysed with sensitive polymerase chain reaction (PCR)-based HPV methods for a study of age-related prevalence of HPV. HPV was identified in 64% of the tumours after PCR amplification of the HPV L1 gene only and in 71% following PCR amplification of both the L1 and E6 genes of HPV. HPV 18 was the most prevalent (52%), followed by HPV 16 (33%) and other types of HPV (15%). The prevalence of HPV was shown to be age-dependent. In women younger than 40 years, HPV was present in 89%, whereas in women 60 years and older, HPV was observed in only 43%. The difference was statistically significant, P<0.005. The HPV-positive adenocarcinomas were represented by an age distribution similar to that of cervical squamous carcinomas with a maximum age, in the 40-49 year old group, whereas the frequency of HPV-negative adenocarcinomas increased with age, typical of most carcinomas occurring in elderly women.

Experience in treatment of metastatic pulmonary carcinoid tumors.

BACKGROUND: The only cure for patients with pulmonary carcinoids is surgery. In the present paper, we report the results of medical treatment of patients with metastatic tumors, their circulating hormone markers, and immunohistochemical profile of the tumors. PATIENTS AND METHODS/RESULTS: The response to systemic antitumoral treatment was studied in 31 patients with metastatic pulmonary carcinoids. Median survival from treatment start was 25 months. Alpha-interferon treatment has resulted in stable disease in 4 of 27 patients (median duration 15 months), while 23 patients showed progressive disease. Somatostatin analogues given as single drug treatment resulted in progressive disease. Streptozotocin and 5-fluorouracil resulted in progressive disease in seven of seven patients. Stable disease was obtained for 8 and 10 months respectively in two of two patients treated with streptozotocin + doxorubicin. Two of eight patients treated with cisplatinum + etoposide showed a significant decrease in tumor size lasting six and eight months respectively, and one displayed stable disease for seven months. Elevation of plasma chromogranin A was seen in 93%. CONCLUSIONS: The results of systemic antitumoral treatment of pulmonary carcinoids with distant metastases are generally discouraging. Chemotherapy with cisplatinum + etoposide, or doxorubicin combined with streptozotocin or paclitaxel may be of value. Alpha-interferon and octreotide offer efficient symptomatic relief, but stabilizes tumor growth in merely 15% of the cases. Plasma chromogranin A is the most frequently elevated tumor marker.

The level of the mitochondrial mutation A3243G decreases upon ageing in epithelial cells from individuals with diabetes and deafness.

We have in a longitudinal study determined the proportion of the mitochondrial A3243G mutation in DNA obtained from cervical cell samples collected from three individuals affected with mitochondrial diabetes and hearing loss during a period of up to 18 years. Using the minisequencing method we were able to sensitively determine the proportion between mutant and normal mitochondrial DNA. Our results demonstrate a constant decrease in the levels of the pathogenic mutation in mitotic tissues of affected individuals with time.

Streptozocin and o,p'DDD in the treatment of adrenocortical cancer patients: long-term survival in its adjuvant use.

BACKGROUND: To evaluate the efficacy of streptozocin and o.p'DDD (SO) in adrenocortical cancer (ACC) patients since other chemotherapeutic regimens have limited effects. PATIENTS AND METHODS: We performed a phase II study with SO therapy in 40 ACC patients (median age 44 years). Oral o,p'DDD administration (1-4 g/d, every day) was given together with intravenous streptozocin (1 g/d for five days, thereafter 2 g once every three weeks). 5HT3-receptor blocker was used as standard premedication for streptozocin. RESULTS: The SO therapy was found to have significant effects on disease-free interval (P = 0.02) as well as on survival (P = 0.01) in adjuvantly treated cases (n = 17) in comparison to the patients who did not get any therapy after complete resection (n = 11). Complete or partial response was obtained in 36.4% of patients with measurable disease (n = 22). The overall two-year and five-year survival rates were 70% and 32.5%, respectively. The presence of metastases at diagnosis was identified as a poor prognostic factor (P = 0.02). CONCLUSIONS: The present study necessitates further randomized clinical study of SO therapy in the treatment of ACC, mainly as adjuvant treatment immediately after curative intended surgery, and could be developed into a regular treatment regimen.

Prognostic markers in patients with typical bronchial carcinoid tumors.

Typical bronchial carcinoids are usually considered fairly benign tumors. Metastases do however occur, and up to 10% of the patients ultimately die from their disease. To identify prognostic markers, we immunostained 43 typical bronchial carcinoids with antibodies against 8 possibly relevant hormones, oncogenes, tumor suppressor genes, adhesion molecules, and proliferation markers. Altogether 12 patients (28%) had metastatic disease, of whom 10 had regional lymph node metastases at diagnosis. Distant metastases have occurred in 5 patients (12%); all of these have died from their disease. Patients with high expression of Ki-67 had shorter survival time (P < 0.01). None of the immunostained hormones correlated to distant metastases or shorter survival time, but gastrin-releasing peptide correlated to metastatic disease (P < 0.05). All patients who died had CD44-negative tumors (P < 0.001). Nuclear nm23 staining correlated to decreased risk for metastatic disease and distant metastases per se (P < 0.01). Bcl-2 and p53 were associated with increased risk for distant metastases (P < 0.05 and P < 0.01, respectively). We conclude that some patients with typical bronchial carcinoids die from their disease and that gastrin-releasing peptide, Bcl-2, and p53 may be of importance for the malignant transformation of the tumor. Moreover, CD44, nm23, and Ki-67 may give valuable prognostic information and help identify the patients at risk of disease-related death.

Uneven distribution of HPV 16 E6 prototype and variant (L83V) oncoprotein in cervical neoplastic lesions.

A previous Swedish study revealed that both prototype and variant HPV16 E6 oncoprotein, occur in about equal numbers in high-grade cervical intraepithelial neoplasia (HCIN), whereas variant HPV16 predominates in invasive cervical squamous carcinoma. Most of the malignant HPV16 variants contain a common mutation, L83V, in the E6 oncoprotein. In the present investigation, 28 HPV16 positive, invasive cervical adenocarcinomas were collected from a total number of 131 adenocarcinomas. These HPV16-positive cases were evaluated with analysis of the E6 gene, using a recently described PCR-SSCP method for identification of the specific mutation (L83V) in the E6 gene. The results obtained were correlated to findings in 103 preinvasive, HCIN, and 31 invasive cervical squamous carcinomas also infected with HPV16. The HPV16 E6 variant L83V was present in 40% of the HCIN lesions, in 54% of the invasive adenocarcinomas, in comparison to 81% of the invasive squamous carcinomas. The difference between HCIN and squamous carcinomas was statistically significant, P < 0.001, whereas the difference between HCIN and invasive adenocarcinomas was not statistically significant, P = 0.604. Prototype HPV16 and its E6 variant L83V are both prevalent in preinvasive and invasive cervical lesions in Swedish women. However, the obvious predominance of HPV16 variant in squamous carcinomas was not seen in adenocarcinomas. A single amino-acid shift in the HPV16 E6 gene appears to result in a different transforming potential in squamous and glandular cervical lesions.

Clonality of precursors of cervical cancer and their genetical links to invasive cancer.

Two problems were the focus of this study. (1) Is precancer and/or invasive cancer of the human cervix a poly- or monoclonal proliferation of neoplastic cells? (2) Are simultaneously present precancers and cancers of the cervix clonally related, or do they arise independently? Microdissection of 37 neoplastic lesions with different degrees of histologic severity in 22 patients followed by polymerase chain reaction-based analysis of X-chromosome inactivation was used as a principal method. Invasive cancers were interpreted as monoclonal because samples invariably showed monoclonal signals. In two thirds of these cases, simultaneously present precursors had the identical X-chromosome inactivation pattern, but in one third the pattern was different. Polyclonality was seen in a subgroup of precursors, where there was no simultaneous presence of invasive cancer. In contrast, when invasive cancer was present, no precursor signaled polyclonality. Data taken together indicate that the pathogenesis of cervical cancer is probably even more complicated than that of other cancers involving selection of subclones from originally polyclonal precursors and possibility of coexistence of precursors of different monoclonal composition. The study also observed that a large field of normal cervical squamous epithelium (approximately 500 basal squamous epithelial cells) with nonrandom X-chromosome inactivation was present. It remains to be further investigated whether this phenomenon represents an embryologic lyonization pattern of X-chromosome inactivation or postembryologic clonal expansion of submorphologically transformed cells.