The role of human papillomavirus DNAs in cervical carcinoma and risk of lymph node metastasis: association with 72-kilodalton metalloproteinase immunostaining

BACKGROUND: The role of human papillomavirus (HPV) as a prognostic factor in cervical carcinoma is not understood completely and little is known regarding the intrinsic mechanisms involved in the metastatic process of HPV positive carcinoma. The authors evaluated HPV status with respect to clinical features in early stage cervical carcinoma, with special emphasis on lymph node spread. The authors also analyzed the relation between HPV, lymph node involvement, and 72-kilodalton (kDa) metalloproteinase immunostaining, an enzyme that cleaves Type IV collagen and may play a role in tumor metastasis. METHODS: Thirty-two patients with International Federation of Gynecology and Obstetrics Stage I and IIA squamous cell cervical carcinoma treated by primary radical surgery were reviewed. Histologic grade of differentiation, tumor size, fractional depth of invasion, and lymph node spread were evaluated with respect to HPV status and 72-kDa metalloproteinase immunostaining. HPV DNA was detected by polymerase chain reaction and the primers potentially recognized at least the following HPV subtypes: 6, 11, 16, 18, 31, 33, 34, 35, 42, 51, 56, and 58. Immunohistochemical staining was performed using the avidin-biotin complex technique. Affinity-purified rabbit anti-72-kDa metalloproteinase antibody was used. RESULTS: HPV DNA was detected in a total of 69% of cases, and HPV-16 was the most frequent type detected. HPV positive carcinomas showed a significantly higher rate of lymph node metastases than HPV negative carcinomas (45% vs. 10%; P = 0.03); similarly, 72-kDa metalloproteinase index was significantly higher (P = 0.001). CONCLUSIONS: These findings suggest a relation between HPV and risk of lymph node metastasis, which may be mediated by an increased production of 72-kDa metalloproteinase.     

Carcinomas of Bartholin''s gland. Histogenesis and the etiological role of human papillomavirus

In this study, we examine 10 primary carcinomas of Bartholin's gland, including seven squamous carcinomas, two adenoid cystic carcinomas, and one adenocarcinoma, as well as four non-neoplastic Bartholin's gland. Six of seven squamous cell carcinomas contained human papillomavirus (HPV) type 16 DNA detectable by the polymerase chain reaction; one of these demonstrated HPV type 16 by in situ hybridization. The two adenoid cystic carcinomas, the adenocarcinoma, and the non-neoplastic Bartholin's gland epithelium showed no evidence of HPV DNA by polymerase chain reaction or in situ hybridization. A panel of eight antibodies (Cam 5.2, B72.3, CEA, EMA, MCA, Lewis X, ER, and PR) demonstrate that the squamous, transition zone, duct, acinar, and myoepithelial cells or Bartholin's gland are antigenically distinct, and are similar to those reported in analogous areas of the uterine cervix. Squamous carcinoma and adenocarcinomas of Bartholin's gland are antigenically similar, and seem to arise from the transition zone of the Bartholin's gland duct. The origin of adenoid cystic carcinomas is more difficult to determine; it is distinct from squamous and adenocarcinomas and seems more likely to arise from myoepithelial cells. We conclude that adenocarcinoma and squamous cell carcinoma of Bartholin's gland arise in the transition zone of Bartholin's gland, which is similar to the transition zone of the uterine cervix. We also show that HPV is associated with Bartholin's gland carcinoma and may play a role in the genesis of malignancy.     

Differential transforming growth factor-beta secretion in adenocarcinoma and squamous cell carcinoma of the uterine cervix

Tumor cells from eight freshly isolated cervical cancers (i.e., four adenocarcinomas and four squamous carcinomas) were analyzed for their production of the immune-inhibitory cytokine transforming growth factor-beta (TGF-beta) in vitro. All fresh adenocarcinomas secreted significant levels of TGF-beta (mean 397, range between 207 and 782 pg/ml/10(5) cells/48 hr). In contrast, no detectable TGF-beta was present in the supernatants from the four fresh squamous carcinoma cultures (P < 0.001). These data suggest that major differences in the secretion of the immunoinhibitory cytokine TGF-beta exist between squamous cell carcinomas and adenocarcinomas of the uterine cervix. Furthermore, these findings suggest that at least some of the differences in the natural biologic behavior, as well as in the response to radiation treatment, between these two histologic types of cervical cancer could be related to differences in secretion of this immune-inhibitory cytokine.     

Prevalence of human papillomavirus types 16 and 18 in penile carcinoma: a study of 41 cases using PCR

AIMS: To determine retrospectively the prevalence of human papillomavirus (HPV) types 16 and 18 in penile carcinomas. METHODS: Forty one surgically resected penile carcinomas from the archives at Queen Mary Hospital, Hong Kong, were reviewed and classified into verrucous carcinoma, and well, moderately, and poorly differentiated squamous cell carcinomas. Paraffin wax embedded tumour tissue was sectioned and analysed for HPV 16 and HPV 18 using the polymerase chain reaction with type specific internal probes. RESULTS: There were seven verrucous carcinomas, and 11 well, 17 moderately, and six poorly differentiated squamous cell carcinomas. Six of the 41 (15%) patients had penile carcinoma containing HPV 16 or HPV 18 DNA, or both, with HPV 16 found in four (10%) and HPV 18 in four (10%). The mean ages of HPV positive and HPV negative groups of patients were 68.5 and 57.6 years, respectively (p < 0.05). None of the seven verrucous and 11 well differentiated squamous cell carcinomas was positive for HPV. The mean age of patients who had these carcinomas was 52.4 years. As a group, these low grade carcinomas occurred in patients younger by more than a decade than those who had carcinomas of the higher grades (mean age 64.4 years; p < 0.01). CONCLUSIONS: Penile carcinomas had much lower rates of infection by HPV 16 or HPV 18 than cervical carcinomas in this Hong Kong population. Based on our findings and on data collated from published findings, it is concluded that penile verrucous carcinomas are not associated with HPV 16 and HPV 18. The overall low prevalence of HPV 16 and HPV 18 in penile carcinomas suggests that other HPV types might be important in the pathogenesis of these tumours.     

Alterations in exon 1 of c-myc and expression of p62c-myc in cervical squamous cell carcinoma

AIMS: To examine human papillomavirus (HPV) positive and negative squamous cell carcinomas of the cervix for structural alterations in exon 1 c-myc; and to investigate the expression pattern of p62, the protein product of c-myc. MATERIAL: Archival paraffin wax embedded tissues of cervical squamous cell carcinomas, stage I and II, retrieved from the files of the department of pathology, University College Cork, Ireland: 40 cases were examined for alterations in exon 1 of c-myc; 57 cases were used for immunocytochemical p62 analysis. METHODS: c-myc exon 1 PCR on HPV positive and negative stage I and II cervical squamous cell carcinomas was performed using primers designed to fragile sites in exon 1 of the c-myc oncogene, which are frequently involved in translocation phenomena and deletions in other neoplasms. This region is bordered by two promoter sequences P1 and P2. In addition, the expression of p62 was evaluated using the monoclonal antibody Mycl-9E10. RESULTS: Alterations in exon 1 of c-myc were shown in 7.5% of squamous cell carcinomas of the cervix. Changes in exon 1 and 2 of c-myc were also found in COLO 320 cells and Raji cells. These alterations were due to small deletions within exon 1 of c-myc, but point polymorphisms occurring within the priming sites (in one case) may also have occurred. The alterations uncovered appeared "clonal," as replicate samples showed the same amplicon band pattern. Expression of c-myc was variable, with cytoplasmic staining patterns predominating. All cases which showed exon 1 alterations were HPV positive and had strong nuclear positivity on p62 immunocytochemistry. CONCLUSIONS: Alterations in exon 1 of c-myc occur in a minority of cervical cancers and there was increased expression of p62 in a cohort of HPV positive and negative cervical squamous cell carcinomas. Exon 1 alterations may provide an alternative route to c-myc activation in early squamous cell carcinoma.     

Antibacterial activity of extracts and constituents of Pelargonium sidoides and Pelargonium reniforme

Tumor angiogenesis is essential for solid tumor growth. The object of this study was to investigate the presence of newly identified angiogenic factor, placenta growth factor (P1GF) in human cervical cancers. The expression of P1GF mRNA was assessed by RT-PCR in 29 patients with cervical cancer. Fifteen out of 29 cervical cancers expressed a certain level of P1GF mRNA. In addition, the expression levels of P1GF mRNA in squamous cell carcinomas were significantly higher than those in adenocarcinomas. There was no correlation between the expression of P1GF mRNA and FIGO stage. These results indicate that the expression of P1GF may be implicated in the promotion of angiogenesis in human cervical squamous cell carcinomas, but not in human cervical adenocarcinomas.     

Mutations in exon 7 and 8 of p53 as poor prognostic factors in patients with non-small cell lung cancer

This study was performed to clarify the different effects of each mutant exon of p53 as indicators of a poor prognosis in patients with non-small cell lung cancer (NSCLC). Tumor tissues of 204 patients with NSCLC were analysed; 96 tumors were stage I, 22 stage II, and 86 stage III. DNA was extracted from frozen specimens and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and direct sequencing were performed to investigate mutations of p53 from exon 5 to exon 8. Seventy-five patients with NSCLC (36.8%) had mutations in p53 which included 72 cases of missense mutations and three cases of non-missense mutations. The overall survival rate of patients with mutant p53 adenocarcinomas was strikingly worse than that of patients whose tumors had wild-type p53 (35.7% vs 53.8%; P=0.041), but no significant difference in survival was found in the patients with NSCLC and squamous cell carcinoma. Mutations in exon 5 of p53 occurred in 33 cases (16.2%), mutation in exon 6 was detected in only one case (0.5%), mutations in exon 7 in 20 cases (9.8%), and mutations in exon 8 in 18 cases (8.8%). The overall survival rate of patients with mutations in exon 7 was worse than that of patients with wild-type p53 in NSCLCs and adenocarcinomas (42.9% vs 56.0%; P=0.025 and 33.3% vs 53.8%; P=0.048, respectively), whereas the overall survival of patients with mutations in exon 5 was almost the same as that of patients with wild-type p53. In addition, the overall survival rate of patients with mutations in exon 8 was strikingly worse than that of patients with wild-type p53 in NSCLCs, adenocarcinomas and squamous cell carcinomas (22.9% vs 56.0%; P<0.001, 19.0% vs 53.8%; P=0.004 and 33.3% vs 62.5%; P=0.042, respectively). Multivariate analysis with the Cox regression model of patients with NSCLC, adenocarcinoma and squamous cell carcinoma indicated that mutations in exon 8 were best correlated with the overall survival rate, followed by lymph node status (P<0.001, P=0.015 and P=0.006, respectively), and mutations in exon 7 of NSCLC were also revealed to have good correlation, followed by lymph node status and mutations in exon 8 (P=0.031). Mutation of p53 was a poor prognostic factor for adenocarcinoma as described previously. Moreover, mutations in exon 8 were more useful indicators of prognosis not only for adenocarcinoma but also for NSCLC. Worse overall survival of the patients with mutations in exon 8 of p53 was suggested to be associated with codon 273 mutations as well as mutations between codon 280 and 285 included into the H2 alpha helix corresponding to residues 278-286. These results suggested that abnormal conformation of H2 alpha helix might play an important role not only in the loss of normal function but also in the acquisition of tumorigenesis. Investigation of mutations in exon 8, especially codon 273 mutation and mutant H2 alpha helix was considered to be a clinically useful approach for determining the prognosis of patients with NSCLC.     

Histopathologic changes seen in esophagectomy specimens from the high-risk region of Linxian, China: potential clues to an etiologic exposure?

Esophageal cancer is one of the most fatal cancers worldwide and is characterized by great variation in rates among different populations. Linxian, a county in Henan Province, located in north-central China, has one of the highest rates of esophageal squamous cell carcinoma in the world. Most squamous cell carcinomas in low-risk populations are attributable to alcohol and tobacco consumption, but the causative agents in high-risk populations are less clear. The prevention and treatment of esophageal cancer in high-risk regions, such as Linxian, are limited by our inability to identify these agent(s). During a preliminary histological review, the authors noticed characteristic findings in the arteries, nerves, and lymph nodes of esophagectomy specimens from Linxian and wondered whether these findings might offer clues to the cause of squamous cell carcinoma (eg, polycyclic aromatic hydrocarbon exposure) in the Linxian population. The purpose of this study was to report these previously undescribed histopathologic changes and to compare their presence and severity with those found in esophageal squamous cell carcinomas and adenocarcinomas from a lower-risk population in the United States. Forty esophagectomies were reviewed, including 13 squamous cell carcinomas from Linxian and 21 squamous cell carcinomas and six adenocarcinomas from the United States. The presence and severity of arteriosclerosis and myxoid degeneration of nerves and the presence of anthracosis in periesophageal lymph nodes were recorded. The prevalence and severity of these findings in the three groups of esophagectomies were compared. The esophageal squamous cell carcinomas from Linxian, China, had a higher prevalence of arteriosclerotic vessels, nerves with myxoid degeneration, and anthracotic lymph nodes than the squamous cell carcinomas from the United States (Wilcoxon test, P < .04 for all comparisons). There were also significant differences in the prevalence of arteriosclerotic vessels and anthracotic lymph nodes between the esophageal squamous cell carcinomas from Linxian and the adenocarcinomas from the United States. Arteriosclerosis and the myxoid degeneration were significantly more severe in the esophageal squamous cell carcinomas from Linxian than in the esophageal squamous cell carcinomas or adenocarcinomas from the United States (Mantel trend test, P < .006 for all comparisons). Arteriosclerotic vessels, nerves with myxoid degeneration, and anthracotic lymph nodes can be seen in association with esophageal squamous cell carcinomas from the high-risk region of Linxian, China. These changes appear to be more prevalent and severe than those seen in association with esophageal squamous cell carcinomas or adenocarcinomas from a low-risk population in the United States. These characteristic changes may be causatively significant and may represent histological evidence of high-level environmental exposure to polycyclic aromatic hydrocarbons.     

Prognostic features of cervical dysplasia associated with specific types of HPV DNA and cytologic features characteristic of HPV infection in dysplasia

OBJECTIVE: To study a possible etiologic relationship between the prognosis of uterine cervical dysplasia, association of type-specific human papillomavirus (HPV) DNA and cytologic features characteristic of HPV infection. STUDY DESIGN: Two hundred thirteen cases of uterine cervical dysplasia were selected in which follow-up survey for more than two years was possible. Frequency of the presence of HPV DNA in the DNA samples was determined by polymerase chain reaction. The cervical scrapings were also examined microscopically for the frequencies of cells with cytologic features characteristic of HPV infection. RESULTS: HPV was positive in 98 cases (46.0%). The high-risk type of HPV was detected at almost the same frequencies in both progressive and regressive states of dysplasia. Cytologic features were more evident in cells infected with the low-risk type of HPV. CONCLUSION: Involvement of an as-yet-unknown factor or factors coupled with infection with the high-risk type of HPV is implicated in the progression of uterine cervical dysplasia. Cytologic features characteristic of HPV infection may serve as a diagnostic marker for a favorable prognosis in dysplasia.     

Usefulness of hybrid capture HPV DNA assay as a diagnostic tool for human papillomavirus infection

The purpose of this study was to determine the usefulness of the hybrid capture HPV DNA assay, a new nonradioactive solution hybridization assay, as a diagnostic tool for human papillomavirus infection. In a total of 234 women, samples for the hybrid capture assay and polymerase chain reaction (PCR) assay were obtained by wiping a swab across the cervix and external os (either a Dacron swab or a cotton swab was used). The papanicolaou smear test (Pap smear) was carried out on all 234 women. Tissue samples for biopsy were obtained by colposcopy from 118 of the women. Fisher exact test was used for statistical analyses. Using the hybrid capture assay, HPV DNA of high- and intermediate-oncogenic-risk type was detected in 23 (13.9%) of 166 samples from women with Pap smear Class I or II, and 48 (70.6%) of 68 with Pap smear Class III, IV or V (p < 0.0001). The HPV DNA type was detected in 18 (29.0%) of 62 samples from those with no evidence of cervical intraepithelial neoplasia and 44 (78.6%) of 56 with cervical intraepithelial neoplasia or squamous cell carcinoma (p < 0.0001). Correlation of the test results between the hybrid capture test and PCR was determined by using the 217 samples in which both test results were available (PCR test results were not obtainable in 17 samples. When PCR is set as a gold standard, the hybrid capture test has high sensitivity (74.6%) and specificity (92.7%). These findings suggest that the hybrid capture HPV DNA assay is a useful method for diagnosing HPV infection in the clinic.     

Clinicopathological significance of Fhit protein expression in stage I non-small cell lung carcinoma

Abnormalities in structure and expression of the FHIT gene have been detected in a considerable fraction of primary lung tumors. Previous reports indicated that FHIT gene alterations can be simply detected by immunohistochemical methods. Therefore, we investigated the association of Fhit expression with clinicopathological features and allelic imbalance (AI) at the FHIT locus in 105 stage I non-small cell lung cancers (NSCLC) by the immunohistological method and PCR analysis. Thirty-six of 105 (34%) tumors showed marked reduction of Fhit immunoreactivity. Fhit expression was markedly reduced in most squamous cell carcinomas (24 of 28, 86%), whereas such a reduction was detected only in a small subset of adenocarcinomas (7 of 67, 10%; P < 0.001). A marked reduction of Fhit protein expression was observed more frequently in patients with a smoking history (32 of 80, 40%) than in patients without a smoking history (4 of 25, 16%; P = 0.013). These results indicate that FHIT gene alterations preferentially occur in squamous cell carcinomas and in smokers. Furthermore, a reduction of Fhit protein expression in tumor cells was associated with a poorer survival of patients with stage I NSCLC, irrespective of histological subtypes of tumors (P = 0.005; log-rank test). Fhit expression was reduced preferentially in tumors with AI at the FHIT locus; however, AI at the FHIT locus did not correlate with patients' survival (P = 0.262; log-rank test). These results suggested that Fhit protein expression could be a useful molecular marker for the prognosis of patients with surgically resected stage I NSCLC.     

Effects of flutamide on pituitary and adrenal responsiveness to corticotrophin releasing factor (CRF)

Although most studies have indicated that Ber-EP4 immunostaining can assist in differentiating epithelial pleural mesotheliomas from adenocarcinomas that metastasize to the pleura, the percentage of positive cases has varied greatly among different studies. Authors of a recent publication concluded that Ber-EP4 has no diagnostic utility in separating these conditions. To determine whether Ber-EP4 has any value in distinguishing mesothelioma from adenocarcinoma, 70 formalin-fixed epithelial pleural mesotheliomas, 20 pulmonary adenocarcinomas, 59 nonpulmonary adenocarcinomas, 4 squamous cell carcinomas of the lung, 6 transitional cell carcinomas, and 31 adenocarcinomas of unknown origin that metastasized to the pleura were stained with this antibody. Reactivity was observed in 18 (26%) of 70 mesotheliomas and in all 20 (100%) of the pulmonary adenocarcinomas, in 55 (93%) of the 59 nonpulmonary adenocarcinomas, in 4 (100%) of 4 squamous cell carcinomas of the lung, in 4 (67%) of 6 transitional cell carcinomas, and in 26 (84%) of 31 adenocarcinomas of unknown origin that metastasized to the pleura. The staining in the mesotheliomas was focal and restricted to a limited number of cells, in contrast with staining in the pulmonary adenocarcinomas in which it was invariably diffuse. The extent of the staining in the nonpulmonary adenocarcinomas and the metastatic adenocarcinomas of unknown origin was less consistent--negative or focal in some cases and diffuse in others. Therefore, while Ber-EP4 seems to be helpful in separating epithelial pleural mesotheliomas from lung adenocarcinomas, its value in distinguishing mesotheliomas from other tumors metastatic to the pleura is more limited and depends largely on the site of origin of the metastatic tumor.     

Cervical cancer survival in a high risk urban population

BACKGROUND: Cervical cancer remains an important public health problem, particularly for the urban minority population. To the authors' knowledge, determinants of cervical cancer survival have not been studied in this high risk population. METHODS: This study included all 158 women diagnosed and treated for invasive cervical cancer from January 1, 1986, through December 31, 1992, at the Grady Memorial Hospital and Clinics (Atlanta, GA). Medical records were abstracted to determine age at diagnosis, race, International Federation of Gynecology and Obstetrics (FIGO) clinical stage, treatment, and survival. Pathologic material was reviewed to confirm the diagnosis. RESULTS: Most patients (80%) were African American, and the stage distribution was similar for African American and white patients. Sixty-six (42%) had FIGO Stage I disease; 50%, Stage II or III; and 8%, Stage IV. Four-year actuarial survival differed significantly according to clinical stage (Ia = 94%, Ib = 79%, II = 39%, III = 26%, IV = 0%). Overall survival was lower for patients with glandular carcinomas than for those with squamous cell carcinomas (26% vs. 55%, P = 0.09). This difference was almost entirely due to increased mortality in patients with Stage Ib adenocarcinomas (53% vs. 88% for squamous cell carcinoma, Stage Ib, P = 0.03). CONCLUSIONS: The major prognostic markers for cervical cancer survival in this high risk patient population were clinical stage and histology, factors identical to those identified for other populations.     

Validation of the Point-EXACCT method in non-small cell lung carcinomas

K-ras point mutations are often detected in part of the lung carcinomas. For the validation of a highly sensitive and rapid assay for known point mutations, Point-EXACCT (Biochim Biophys Acta 1998; 1379:42-52), we analyzed 89 non-small cell lung carcinomas and compared the results with two sequencing methods. No point mutations were found with double-stranded sequencing. Single-stranded sequencing detected six patients positive for K-ras codon 12. When Point-EXACCT was used, K-ras codon 12 mutations were detected in 8 of 52 patients with squamous cell carcinomas, 10 of 29 patients with adenocarcinomas, and 3 of 8 patients with large cell carcinomas. The finding of K-ras mutations in squamous cell carcinomas is explained by the high sensitivity of the method. Therefore, Point-EXACCT may be applicable to detection of those alterations occurring at a low frequency among an excess of cells with wild-type DNA.     

Comparison of conventional PAP smears with thin layer specimen (liquid-based PAP test) and correlation with cytopathological findings with HPV status using the hybrid capture system

Cervical smears of 554 outpatients of a hospital were examined using a blinded, split sample match pair protocol for which a conventional PAP-smear (CS) was first prepared with Cervex brush and the reminder of the sample was used for the thin-layer-preparation (TLP) according to the manual CytoRich System. The preparations of the two methods were compared with respect to quality and to sensitivity for atypias. In addition the HPV status was determined on the same cell suspension in cases with borderline changes (BLC) and dysplasias including carcinoma using the Hybrid Capture System. The use of TLP reduced the proportion of suboptimal preparations by more than 50% (14.6% vs. 35%) and eliminated the only inadequate preparation registered in CS. The DSP detected more than twice as many dysplasias of all degrees as CS (3.4% vs. 1.4%) and reduced the proportion of BLC to one third (3.2% vs. 9.6%). The percentages of cases positive for high- and intermediate-risk HPV in preparations with BLC, LSIL and HSIL were 17, 62.5% and 100% respectively. The TL-method improves significantly the efficiency of PAP-smears and allows the typing of HPV which is of clinical importance for the management of low grade squamous intraepitelial lesions and borderline changes. The findings speak against the further use of CS for cervical screening.     

Cervical intraepithelial neoplasia (CIN) and human papillomavirus (HPV) infection

Many studies have shown a strong correlation between CIN and HPV infection. Molecular biology has allowed identification of types of HPV which seem to be connected, more frequently than others, to dysplastic lesions. Physical state of HPV-genome seems to play an important role in the development of cervical cancer. In this study the HPV-genome has been searched in tissue specimens obtained from 34 women affected by CIN II and III. All patients underwent laser conization. Immediately before treatment, colposcopically directed biopsies of the cervical lesion and of the areas with no colposcopically apparent disease were taken and on these samples, HPV-DNA has been searched, isolated and analysed for HPV types and physical state. Histologic examination on cones showed 6 cases of CIN II (3 with HPV), 24 cases of CIN III (14 with HPV), 1 microinvasive carcinoma and 3 with no residual lesion. Southern blot analysis detected HPV-DNA in 4 cases of CIN II (16.7%) and in 20 cases of CIN III (70.6%). In 50% of CIN II and 85% of CIN III HPV 16 DNA has been found and in the remaining 50% of CIN II and 15% of CIN III HPV 31 DNA has been detected. All CIN II and 14 cases of CIN III showed episomal HPV-DNA. Integrated HPV-DNA has been found in 3 cases of CIN III and the other 3 cases of CIN III showed both integrated and episomal HPV-genome. Integrated form has been noticed only for HPV 16 type. In no case of colposcopically normal tissue has HPV-DNA been found. These data seem to confirm the strong correlation between HPV 16 type, which often has integrated form, and CIN III strengthening the hypothesis of its potential oncogenic action.     

Mutations of K-ras oncogene and absence of H-ras mutations in squamous cell carcinomas of the lung

Mutations of the K-ras gene have been implicated in the pathogenesis of human lung adenocarcinomas. In most studies published so far, squamous cell lung cancers harbored ras mutations only exceptionally or no mutations were detected at all. We have examined 141 lung tumor DNA samples for mutations in codons 12, 13, and 61 of K-ras and H-ras oncogenes. A large panel of 118 squamous cell carcinomas was included in the study. For K-ras codon 12, we used a sensitive two-step PCR-restriction fragment length polymorphism method which detects <1% of mutated DNA in the sample. K-ras mutations were found in 17 tumors (12%; 14 in codon 12 and 3 in codon 13). Among 19 adenocarcinomas, mutation was revealed in 7 samples (37%). Of these, one sample harbored two point mutations in codon 12. Nine mutational events were found in squamous cell carcinomas (8%, one adenosquamous carcinoma included, all in codon 12). Of four large cell carcinomas, one contained a mutation. Mutant-enriched PCR products harboring mutations were directly sequenced. Fifteen mutational events were G-->T transversions or G-->A transitions, one was a G-->C transition, and one sample revealed a frameshift deletion of one G from codon 12. Similar mutational spectrum was found in both squamous cell carcinomas and adenocarcinomas, suggesting similar carcinogenic pathways in both histological types of the tumor. The presence of mutations did not correlate with the stage of the disease. Moreover, we analyzed all samples for mutations in codons 12, 13, and 61 of the H-ras gene. We found only one mutation in codon 12. Thus, H-ras mutations apparently play an inferior role in lung carcinogenesis. We conclude that mutations of the K-ras oncogene can play a role in the development of not only lung adenocarcinomas but also of a subset (about 8%) of squamous cell carcinomas.     

Expression of Ets-1 transcription factor in relation to angiogenesis in the healing process of gastric ulcer

Psoralen and UVA (PUVA) photochemotherapy is associated with a dose-dependent increased risk of nonmelanoma skin cancer in patients treated for psoriasis. Like ultraviolet B radiation, PUVA is both mutagenic and immunosuppressive and may thus act as a complete carcinogen; however, the reversed squamous to basal cell carcinoma ratio (SCC:BCC) in PUVA-treated patients, also seen in immunosuppressed renal transplant recipients, suggests a possible cofactor role for human papillomavirus (HPV) infection. In this study we examine a large series of benign and malignant cutaneous lesions for the presence of HPV DNA from patients treated with high dose (> or =500 J per cm2) ultraviolet A. A panel of degenerate primers based on the L1 (major capsid protein) open reading frame was employed, designed to detect mucosal, cutaneous, and epidermodysplasia verruciformis HPV types with high sensitivity and specificity. HPV DNA was detected in 15 of 20 (75%) non-melanoma skin cancer, seven of 17 (41.2%) dysplastic PUVA keratoses, four of five (80%) skin warts, and four of 12 (33%) PUVA-exposed normal skin samples. The majority of HPV positive lesions contained epidermodysplasia verruciformis-related HPV including HPV-5, -20, -21, -23, -24, and -38. Possible novel epidermodysplasia verruciformis types were identified in further lesions. Mixed infection with epidermodysplasia verruciformis, cutaneous, and/or mucosal types was present in six of 30 (20%) of all HPV positive lesions, including in normal skin, warts, dysplastic PUVA keratoses, and squamous cell carcinomas. The prevalence and type of HPV infection in cutaneous lesions from PUVA-treated patients is similar to that previously reported in renal transplant-associated skin lesions, and suggests that the role of HPV in PUVA-associated carcinogenesis merits further study.