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Cyro Festa Neto

Publications and source records attributed to Cyro Festa Neto.

10 recordsLinked to original sources
PubMed2005

Nucleolar organizer region staining patterns in paraffin-embedded tissue cells from human skin cancers.

BACKGROUND: Increased number of nucleoli (nucleolar organizer regions, NORs) with abnormal shapes and sizes, including small dots, has been used as prognostic tools to evaluate tumor proliferation levels and troublesome borderline lesions. In this study, NOR patterns of skin cancers were performed in the search of a valuable prognostic method to complement other histological procedures. METHODS: Paraffin-embedded tumor tissue was obtained from basal and squamous cell carcinomas, cutaneous malignant melanoma, premalignant lesions, and Skmel-28 human melanoma cells. Slices were dewaxed and AgNOR stained. The patterns were scored and submitted for statistical analyses. RESULTS: All types of cancer cells showed variable numbers of abnormally shaped nucleoli and dot-like structures. Only tumor cells presented four or more nucleoli, with or without dots, while 85% of the normal cells had one single NOR without dots. Most data were statistically significant when compared to normal cells. As a whole, squamous cell carcinoma and malignant melanoma tumor cells had less NOR alterations than basal cell carcinoma (BCC) tumor types. CONCLUSIONS: Changes in the number and shape of nucleoli present in malignant cells could be attributed to increased levels on rDNA transcription on cancer cells, besides abnormal remodeling of chromatin, which could disrupt proper nucleoli association. Increased genetic alterations on malignant basal cells could contribute to impair invasive and migration abilities of BCC tumors.

Basal Cell Carcinoma↗
PubMed2004

HPV typing in Brazilian patients with epidermodysplasia verruciformis: high prevalence of EV-HPV 25.

BACKGROUND: Epidermodysplasia verruciformis is a rare genetic disorder characterized by development of lesions associated with HPV#5 or HPV#8 in early childhood; malignant transformation occurs in approximately half of individuals during adulthood. OBJECTIVE: Our goal was to study the presence and spectrum of EV-HPV types in Brazilian EV patients, a population that had never been studied in this regard. PATIENTS AND METHODS: Forty-one biopsies from different lesions (benign and skin tumors) and one biopsy from clinically normal skin from each of 20 Brazilian patients with EV were studied for HPV typing using nested PCR. RESULTS: EV-HPV DNA was detected in all 41 skin lesions of the patients and was also identified in specimens considered as normal skin from 8 patients (40%). In this study HPV-EV 25 was the most prevalent (70%), and HPV 14d (67%) was highly associated with malignant lesions. CONCLUSION: EV-HPV 25 was the most prevalent in our study. The noteworthy association of EV-HPV type 14d with skin cancers suggests its possible oncogenic role in malignant transformation in this population.

Adolescent↗
PubMed2004

Repetitive DNA alterations in human skin cancers.

Repetitive sequences constitute landmarks for genome regulation, evolution, and chromatin architecture. Patterns of specific and non-specific repetitive sequences change in many types and stages of tumor cells, characterized by band loss, gain, and (de) increased staining of pre-existing bands. In this work, repetitive DNA was studied in search of genome instability of skin cancers: basal and squamous cell carcinomas (BCC and SCC), malignant melanoma (MM), melanocytic nevus (MN), and actinic keratosis (AK) lesions. DNAs were extracted from blood and tumor samples from 21 BCC, 7 SCC, 11 MM and 7 lesions. Banding patterns were obtained by random amplification of polymorphic DNA (RAPD), and specific D9S50 and D9S52 microsatellites (9p21). D9S50 patterns revealed microsatellite instability (MSI) and/or loss of heterozygosity (LOH) in 36% BCC, 25% SCC, and 57% MM tumors. D9S52 microsatellite showed 28.5%; 42.8%; and 71.4% altered tumors, respectively. No microsatellite alterations were found in MN and AK. On the other hand, genomic rearrangements detected by RAPD were present in 100% tumors. In BCC, the mean number of tumor DNA alterations showed predominant gain of bands. On the contrary, MM samples presented loss, or decreased intensity signal of RAPD bands. Genome alterations in skin cancers would result from chromosomal rearrangements, aneuploidy and/or polysomies. The low-cost and quick RAPD technique may reveal unknown genes or DNA sequences associated with tumor development and progression, and may be easily implemented in clinical diagnosis.

DNA, Neoplasm↗
PubMed2003

Polymorphisms of the interleukin 10 gene promoter in patients from Brazil with epidermodysplasia verruciformis.

BACKGROUND: Epidermodysplasia verruciformis (EV) is a rare genetic disorder characterized by development of lesions associated with human papillomavirus in early childhood and malignant transformation in approximately half of individuals during adulthood. The persistence of human papillomavirus infection in EV is thought to be a result of an immunogenetic defect, which determines the generation of several cytokines capable of down-regulating cell-mediated immunity. OBJECTIVE: We sought to study the prevalence of interleukin 10 (IL-10) promoter polymorphisms in skin biopsy specimens of patients with EV compared with DNA samples from healthy individuals. Patients and methods DNA samples extracted from normal skin of 22 patients from Brazil with EV and blood samples from 27 healthy Brazilian individuals were studied for IL-10 promoter polymorphisms using restriction fragment length polymorphism analysis. RESULTS: The patients with EV showed an increased rate of low-production genotypes of IL-10 compared with control subjects (P =.003). Patients with EV and skin cancer were more likely to have low-production IL-10 genotypes than patients with benign forms of EV. CONCLUSION: IL-10 genotypes associated with low levels of IL-10 production may have an important role in the pathogenesis of EV, including the susceptibility for development of skin cancer in patients with EV.

Brazil↗
PubMed2003

Nonspecific cell-mediated immunity in patients with epidermodysplasia verruciformis.

Epidermodysplasia verruciformis (EV) is a rare disease that usually begins in childhood and is characterized by a generalized infection by human papilloma virus (HPV), frequent associations with cutaneous carcinomas, and abnormalities of cell-mediated immunity (CMI). We studied nonspecific CMI in 13 patients with EV by bacterial skin tests, allergic reactions to dinitrochlorobenzene (DNCB), measurement of responses to phytohemagglutinin (PHA), and quantification of T lymphocytes and T lymphocytes subsets in peripheral blood. Impairment of CMI was manifested by the cutaneous anergy to a variety of common skin antigens and, by the reduction of the lymphocyte transformation to PHA. There were no correlation between the severity of cases and abnormalities of CMI in our patients, however; the impairment of CMI was lower in cases of short duration, suggesting that the impairment of CMI in EV might reflect a long period of disease.

Adolescent↗
PubMed2003

Seborrheic Keratosis-like lesions in patients with epidermodysplasia verruciformis.

Epidermodysplasia verruciformis (EV) is a rare genodermatosis characterized by disseminated infection by human papillomavirus (HPV) and malignant transformation of the lesions in about half of the patients. Two phenotypes of EV have been described according to their propensity to develop malignant tumors. The benign form of EV presents a singular type of lesions comprised of flat warts widely disseminated. The malignant form of EV is highly polymorphic and presents as malignant skin tumors, predominantly basal and squamous cell carcinomas, on sun-exposed sites. The seborrheic keratosis-like (SK) lesions in patients of EV have been reported to be associated with the malignant phenotype. In this work, we documented the behavior of SK-like lesions in nine patients with EV, through clinical observations as well as histological and immunohistochemical findings. We suggest that the HPV infection may promote the occurrence of SK-like lesions in EV patients. Despite the fact that we did not observe any malignant transformation of these lesions in our series of patients, this possibility was not completely excluded.

Adolescent↗
PubMed2002

Web site for training nonmedical health-care workers to identify potentially malignant skin lesions and for teledermatology.

The development of a Web site to enable nonmedical health professionals to screen skin potentially malignant skin lesions is described. A nurse assistant and a dermatologist tested the Web site. An electronic clinical form was developed to allow a nurse assistant to send case reports and photographs for remote diagnosis by a dermatologist. The nurse assistant photographed the lesions of 92 patients who presented some kind of dermatological condition. The images were then sent for evaluation by the dermatologist followed by in person examination by the same physician. The diagnoses, which resulted from the examination in person and, in some cases, the biopsy results, were compared with the diagnostic impressions of the nurse assistant and with the diagnostic hypothesis of the dermatologist at a distance. The lesions were classified as either malignant or nonmalignant. Kappa statistics showed a high association between the suspected malignity and nonmalignity of the lesions between the dermatologist (p = 6.01 x 10(-9)) and the nurse assistant and between the diagnosis at distance and in person (p < 1.0 x 10(-14)). The Web site allowed a nurse assistant to screen for potentially malignant skin lesions and, thus, proved to be appropriate for a large-scale test.

Allied Health Personnel↗