[The occupational doctor, a comprehensive point of reference for the health at work. An experience of management of mental patients at work]. / Il medico competente, riferimento globale della prevenzione in azienda: l'esperienza nella gestione del disagio psichiatrico.

Sime essential conditions are necessary to place and keep on duty a mental patient: a correct diagnosis and therapy, a continuos consultation between doctors (family, NHS and occupational doctor), an easy working environment, a sensible leader and manager and a good steering committee. The absence of these elements takes to the end of employment condition. Occupational doctor is a point of reference to manage the health of mental worker, to prepare for a well disposed environment at work and to keep relationship between factory and NHS.

CDKN2A and CDK4 mutation analysis in Italian melanoma-prone families: functional characterization of a novel CDKN2A germ line mutation.

Physical interaction between CDKN2A/p16 and CDK4 proteins regulates the cell cycle progression through the G1 phase and dysfunction of these proteins by gene mutation is implicated in genetic predisposition to melanoma. We analysed 15 Italian melanoma families for germ line mutations in the coding region of the CDKN2A gene and exon 2 of the CDK4 gene. One novel disease-associated mutation (P48T), 3 known pathological mutations (R24P, G101W and N71S) and 2 common polymorphisms (A148T and Nt500 G>C) were identified in the CDKN2A gene. In a family harbouring the R24P mutation, an intronic variant (IVS1, +37 G>C) of uncertain significance was detected in a non-carrier melanoma case. The overall incidence of CDKN2A mutations was 33.3%, but this percentage was higher in families with 3 or more melanoma cases (50%) than in those with only 2 affected relatives (25%). Noteworthy, functional analysis established that the novel mutated protein, while being impaired in cell growth and inhibition assays, retains some in vitro binding to CDK4/6. No variant in the p16-binding region of CDK4 was identified in our families. Our results, obtained in a heterogeneous group of families, support the view that inactivating mutations of CDKN2A contribute to melanoma susceptibility more than activating mutations of CDK4 and that other genetic factors must be responsible for melanoma clustering in a high proportion of families. In addition, they indicate the need for a combination of functional assays to determine the pathogenetic nature of new CDKN2A mutations.

DNA damage-associated dysregulation of the cell cycle and apoptosis control in cells with germ-line p53 mutation.

Lymphoblastoid cell lines (LCLs) with heterozygous p53 mutations at residues 286A, 133R, 282W, 132E, and 213ter were established from five independent Li-Fraumeni syndrome families. When cell cycle regulation in response to gamma-irradiation was studied, these LCLs showed an abnormal G1 checkpoint associated with defective inhibition of cyclin E/cyclin-dependent kinase 2 activity in all cases except for 282W LCL, which showed a normal G1 checkpoint. On the other hand, the control of S-phase-G2 as determined by cyclin A/cyclin-dependent kinase 2 activity was defective in all these LCLs. The mitotic checkpoint was also defective in the two LCLs analyzed as either competent or incompetent for G1 arrest. When radiation-induced apoptosis, which requires wild-type p53 function under optimal conditions, was studied, all of these LCLs showed significant failure compared to normal LCLs. These findings indicate that although p53-dependent transactivation and G1-S-phase cell cycle control are variably dysregulated, the induction of apoptosis and control of the cell cycle at S-phase-G2 and the mitotic checkpoint in response to DNA-damaging agents are consistently dysregulated in heterozygous mutant LCLs. This suggests that these dysfunctions underlie, at least in part, the susceptibility of Li-Fraumeni syndrome families to cancer. Furthermore, the approach presented is a potentially useful method for studying individual carriers of different germ-line p53 mutations and different biological features.

Papillomavirus, p53 alteration, and primary carcinoma of the vulva.

Twenty-nine samples from 28 cases of vulvar squamous cell carcinoma, of which 13 fulfilled the criteria of the bowenoid subtype (mean age 45 years, range 31-68) and 16 of the usual subtype of invasive squamous cell carcinoma (ISCC) (mean age 67.5 years, range 34-83) were investigated for human papillomavirus (HPV) DNA, TP53 alterations, and mdm2 and bcl-2 gene product deregulation. Microscopically all the bowenoid subtype cases (group I) showed a high-grade intraepithelial (VIN 3, carcinoma in situ) lesion associated with early invasive carcinoma in six cases and overt invasive carcinoma in one. By contrast, no evidence of early carcinoma was present in the ISCCs (group II). By in situ hybridization and/or Southern blot hybridization or polymerase chain reaction (PCR), HPV DNA was detected in all cases of group I and in four of 16 cases (25%) of group II, two only by Southern blot after PCR. By single-strand conformation polymorphism and immunocytochemistry only wild-type TP53 and absence of detectable p53 product, respectively, were found in all cases of group I, i.e., in high-risk HPV-positive carcinomas, whereas mutations and/or p53 overexpression accounted for 75% in group II, i.e., in mainly HPV-negative carcinomas. The TP53 gene mutations observed in invasive carcinomas were significantly related to node-positive cases (p = 0.04). Taken together and in agreement with in vitro data, these results support the view that an alteration of TP53, gained either by interaction with viral oncoproteins or by somatic mutations, is a crucial event in the pathogenesis of vulvar carcinomas, but that TP53 mutations are mainly associated with disease progression. Finally, a preliminary immunocytochemical analysis seems to speak against the possible involvement of both MDM2 and BCL-2 gene products in the development of vulvar carcinoma.

Genetic evidence for an independent origin of multiple preneoplastic and neoplastic lung lesions.

Patients with a primary cancer in the lung or in the upper aerodigestive tract have an increased risk of developing synchronous or metachronous second primary lung tumors. This phenomenon has been related to the chronic exposure of the bronchial tree to carcinogens through a so-called "field cancerization" process. This study was designed to investigate at the somatic level the genetic basis of the field cancerization effect in patients having multiple simultaneous neoplastic and preneoplastic lesions of the lung. The pattern of specific genetic changes occurring with high frequency and in early stages of lung carcinogenesis including p53 mutations, deletions of chromosome 3p, and K-ras mutations, was investigated by immunocytochemical, cytogenetic, and molecular approaches in 11 synchronous lesions of five patients with multiple lung cancers. Different genetic lesions were observed in all of the pathological specimens analyzed from each patient. The pattern of these changes was different both in topographically distant or adjacent lesions and in tumors with the same histopathological diagnosis supporting their independent origin. The present data provide further evidence of the clinical relevance of the field cancerization process, and support the use of genetic markers in the differential diagnosis of recurrence or metastasis versus second primaries of the lung.

Epstein-Barr virus genomes in undifferentiated and squamous cell nasopharyngeal carcinomas in Italian patients.

Although undifferentiated carcinoma (UC) and squamous cell carcinoma (SCC) of the nasopharynx are regarded as two distinct histopathologic and clinical entities, it is unclear whether, like UC, SCC carries Epstein-Barr virus (EBV) genomes. We used the polymerase chain reaction (PCR) on paraffin-embedded biopsy specimens to test for the presence of EBV DNA in 20 cases of UC and 9 cases of SCC. Multiple copies of the viral genome were regularly detected in all UCs; however, of the nine cases of SCC, seven had no detectable EBV DNA and two contained viral genomes in a low copy number. In parallel, a marked difference in the serum levels of anti-EBV antibodies between patients with UC and SCC was found. Our findings provide evidence for the specific association of EBV with UC in Italian patients and prove by means of a highly sensitive molecular technique that SCC is occasionally related to EBV DNA. Because of the absence of EBV DNA in most cases of SCC and the minimal viral DNA copy number in the few EBV-associated cases of SCC, a different pathway of oncogenic transformation and growth of the nasopharyngeal epithelium is suggested for SCC and UC.

HPV detection and p53 alteration in squamous cell verrucous malignancies of the lower genital tract.

We examined five cases of verrucous carcinoma (VC) and two cases of giant condyloma of Buschke-Löwenstein (GCBL) associated with invasive squamous cell carcinoma (ISCC), by immunocytochemistry and molecular techniques. Neither human papillomavirus (HPV) footprints nor p53-altered expression and/or mutation were observed among the cases of VC. By contrast, both cases of GCBL with ISCC turned out to be HPV 6 or 11 positive, showed overexpression of p53 and, one of the two, a mutation in the nucleotide sequence of this tumor suppressor gene. The results point out that VC and GCBL with ISCC, in spite of some morphologic similarities, are two distinct entities, the former being unrelated to both HPV and p53 inactivation and the latter related to both. Regarding p53, immunocytochemical and molecular data on GCBL with ISCC suggest a role of mutant p53 in the progression of malignancy into invasion.

Gene p53 mutations are restricted to poorly differentiated and undifferentiated carcinomas of the thyroid gland.

The p53 gene was analyzed in tumor specimens obtained from 52 patients with various types of carcinoma of the thyroid gland by a combined molecular and immunocytochemical approach. The histologic types included 37 well-differentiated papillary and follicular carcinomas, 8 poorly differentiated, and 7 undifferentiated carcinomas. The p53 gene was shown to be unaffected in all differentiated tumors by single-strand conformation polymorphism analysis. However, in two out of eight (25%) of poorly differentiated carcinomas and five out of seven (71%) undifferentiated carcinomas, p53 mutations were identified and subsequently characterized by DNA sequencing. One undifferentiated carcinoma displayed two areas with varying degrees of differentiation. The comparative analysis of the p53 gene, in both the more and the less differentiated area of this tumor, clearly showed that the p53 mutation was confined to the latter component of the tumor specimen. These results indicate that mutations of the p53 gene are associated with the most aggressive histologic types of thyroid tumors, such as the undifferentiated carcinoma and, to a certain extent, the poorly differentiated carcinoma, and that the alterations of this gene represent a late genetic event in human thyroid carcinogenesis.

Deletions of 17p and p53 mutations in preneoplastic lesions of the lung.

Cytogenetic and p53 mutation analysis in two cases of severe dysplasia of the bronchial epithelium in lung cancer patients and p53 immunostaining in a third one are reported. The finding of both chromosomal deletions of 17p and p53 mutation indicates that these changes may take place early in the process of lung carcinogenesis.

Human papillomavirus genomes in male urethral cells.

Sixty-four samples of urethral cells from male sexual partners of women with genital human papillomavirus (HPV) infection were analyzed for the presence of HPV types 6, 11, 16, and 18 by polymerase chain reaction (PCR) followed by slot blot hybridization. Additional samples from 37 of these subjects were analyzed for the presence of viral cytopathic effects by conventional cytology. By PCR, HPV DNA was detected in 21% (14/64) of samples. By cytology, 16% (6/37) of the samples showed cellular changes consistent with HPV infection. Polymerase chain reaction and cytology results were concordant for presence and absence of HPV in 5 and 28 cases, respectively. Three additional HPV-positive cases were obtained with PCR in the cytologically negative samples. The cytologic abnormalities were found to be associated with the presence of both low-risk HPV types and meatal acetoreactivity. On the contrary, HPV DNA positivity by PCR was unrelated to viral type and peniscopic findings. Urethral HPV infection was detected by PCR in 30% of males with visible penile lesions and in 18% of those without. These results indicate that PCR analysis of urethral samples is a helpful adjunct to cytology for the detection of HPV DNA in absence of cytologic evidence of infection.

HPV DNA in intraepithelial neoplasia and carcinoma of the vulva and penis.

Surgical specimens of 15 patients with early and 12 patients with advanced squamous cell carcinoma of the vulva and the penis were examined for the presence of human papillomavirus (HPV) type 6, 11, 16, and 18 DNA by Southern blotting (SB) and polymerase chain reaction (PCR) analysis. By SB, HPV type 16 DNA was detected in all early carcinomas and 2 of 12 cases of advanced squamous cell carcinoma (ISCC) of the vulva and penis. PCR revealed HPV DNA in four additional cases of vulvar and penile ISCC negative by SB. Three cases contained HPV16 and one HPV18. Two cases of vulvar and penile Buschke-Löwenstein (BL) tumor with malignancy and one case of vulvar verrucous carcinoma were also examined by both techniques. While BL tumors were associated with DNA of HPV6 or 11, no HPV association was found for verrucous carcinoma. Our results confirm that the detection rate of HPV DNA in early vulvar and penile carcinomas is much higher than in invasive carcinomas. In addition, we have shown that in the lower genital tract, 50% of cases of ISCC are HPV16 correlated. The absence of HPV DNA (types 6, 11, 16, and 18) in the remaining 50% of cases of ISCC thus suggests that vulvar and penile ISCC may have more than one pathogenetic pathway.

Simultaneous in situ hybridization for DNA and RNA reveals the presence of HPV in the majority of cervical cancer cells.

Thirteen cases of invasive squamous cell carcinoma of the uterine cervix containing HPV types 16 or 18 DNA sequences, as detected by Southern blot analysis, were investigated by in situ hybridization on routine paraffin sections, using 35S nick-translated DNA probes. Simultaneous in situ hybridization for DNA and RNA showed that in ten out of 13 cases (77%) the percentage of tumor cells containing HPV 16 or 18 varied from 75 to 100%. In one case, harboring both in situ and invasive carcinoma, the same type of HPV DNA was detected in both components. This finding suggests that neoplastic cells retained the viral genome during progression to invasiveness.

Refined localization to contiguous regions on chromosome 10q of the two genes (H4 and RET) that form the oncogenic sequence PTC.

In this report we confirm the localization of the human RET proto-oncogene to chromosome 10q11.2, both by Southern blot analysis of a panel of human-rodent somatic cell hybrids and by in situ hybridization on human metaphase chromosomes. Previously, we had assigned to the same chromosome region the gene termed H4. In about 25% of papillary thyroid carcinomas, this gene was shown to rearrange with RET to give rise to the transforming sequence PTC. The analysis of different cell hybrids containing subfragments of chromosome 10, in conjunction with pulse field gel electrophoresis, established that H4 is mapped distally to RET at a distance not less than 280 kb. These findings suggest that intrachromosomal rearrangements are responsible for PTC activation in papillary thyroid carcinomas.

PTC is a novel rearranged form of the ret proto-oncogene and is frequently detected in vivo in human thyroid papillary carcinomas.

We recently detected a novel activated oncogene by transfection analysis on NIH 3T3 cells in five out of 20 primary human thyroid papillary carcinomas and in the available lymph node metastases. We designated this transforming gene PTC (for papillary thyroid carcinoma). Here we describe the molecular cloning and sequencing of the gene. The new oncogene resulted from the rearrangement of an unknown amino-terminal sequence to the tyrosine kinase domain of the ret proto-oncogene. This gene rearrangement was detected in all of the transfectants and in all of the original tumor DNAs, but not in normal DNA of the same patients, thus indicating that this genetic lesion occurred in vivo and is specific to somatic tumors. Moreover, the transcript coded for by the fused gene was detected in an additional PTC-positive human papillary carcinoma for which mRNA was available.

High frequency of activation of tyrosine kinase oncogenes in human papillary thyroid carcinoma.

We had previously detected a transforming oncogene, designated PTC, in 25% of 20 papillary thyroid carcinomas. In order to characterize further the transforming activity of this tumour histotype, a new panel of tumour specimens from 16 patients was analysed by using a modified calcium phosphate-DNA coprecipitation transfection protocol. Tumour DNA from 10 patients (62%) displayed a transforming activity due to activation of three different oncogenes identified in four cases as PTC, in four cases as TRK, and in two cases as N-RAS. The same structural alterations of PTC and TRK (gene rearrangements) as well as of N-RAS (point mutation) detected in the NIH3T3 transformants, were also found in the original tumour DNAs, thus indicating that their activation was not due to transfection procedures. Since both PTC, a novel rearranged form of RET, and TRK display a tyrosine protein kinase activity, it is proposed that the activation of this class of oncogenes is specifically involved in the pathogenesis of papillary thyroid cancer.

Human fibroblast interferon adjuvant to CO2 laser in the treatment of recurrent juvenile laryngeal papillomatosis: experience with 7 cases.

Preliminary results of adjuvant human fibroblasts interferon (IFN beta) given after CO2 laser excision in recurrent laryngeal papillomatosis in 7 adult patients are reported. Diagnostic procedure included histologic and immunohistochemical investigations to demonstrate the presence of viral cytopathic effect and for characterization of the virus. All patients underwent CO2 laser excision under general anesthesia followed by administration of IFN beta intramuscularly at the dose of 4 x 10(6) IU/day for 10 consecutive days. In the presence of complete remission, patients were followed without further therapy; in the presence of partial remission, a new combined treatment was established. All patients had a complete remission after combined treatment, but 4 subsequently developed recurrences. Treatments were always well tolerated; even cirrhotic patients showed no side effects.

The oncogene associated with human papillary thyroid carcinoma (PTC) is assigned to chromosome 10 q11-q12 in the same region as multiple endocrine neoplasia type 2A (MEN2A).

In this report we assigned to chromosome 10q the human oncogene PTC frequently associated with the papillary type of thyroid carcinoma. Using an informative panel of human-mouse somatic cell hybrids and 'in situ' hybridization to human metaphase chromosomes, we localized the PTC gene at bands q11-q12 of chromosome 10. These bands belong to one of the two regions on chromosome 10 linked to the cancer syndrome multiple endocrine neoplasia type 2A (MEN2A). Therefore, it is suggested that genes clustered in certain regions of chromosome 10 could be involved in the developmental regulation of the thyroid gland.