Molecular monitoring by CDKN2A/p16INK4A and RB1 gene methylation in breast cancer

SUMMARY OBJECTIVE: This prospective study aimed to provide a comprehensive analysis of the methylation status of two pivotal genes, CDKN2A/p16INK4A (cyclin-dependent kinase inhibitor 2A) and RB1 (retinoblastoma transcriptional corepressor 1), in breast cancer patients. METHODS: Samples were obtained from 15 women diagnosed with breast cancer and who underwent a total mastectomy. DNA was extracted from the tumor, non-tumor tissue, and peripheral blood (circulating cell-free DNA). The methylation pattern of cell-free DNA extracted from blood collected on the day of mastectomy was compared with the methylation pattern of cell-free DNA from blood collected 1 year post-surgery. The methylation analysis was carried out by sodium bisulfite conversion and polymerase chain reaction, followed by electrophoresis. RESULTS: Methylation of CDKN2A/p16INK4A was identified in 13 tumor samples and 12 non-tumor tissue samples. Two patients exhibited CDKN2A/p16INK4A methylation in the cell-free DNA of the first blood collection, while another showed methylation only in the cell-free DNA of the subsequent blood collection. Regarding RB1, 11 tumors and 8 non-tumor tissue samples presented methylation of the gene. CONCLUSION: This study presents a novel approach for monitoring breast cancer patients through the analysis of cell-free DNA methylation. This analysis can detect changes in methylation patterns before any visible sign of cancer appears in breast tissue and could help predict the recurrence of malignant breast tumors.

Sweet Syndrome in childhood

AbstractSweet syndrome or acute febrile neutrophilic dermatosis is a recurrent and rare skin disease caused by the release of cytokines, with diverse possible etiologic causes. It presents clinically with polymorphic skin lesions, fever, arthralgia, and peripheral leukocytosis. In general, it is associated with infections, malignancy and drugs. It usually regresses spontaneously and treatment is primarily to control the basic disease. The authors report the case of a child of 1 year and 11 months who developed Sweet syndrome.

Você conhece esta síndrome? / Do you know this syndrome?

A Síndrome de Bloch-Sulzberger (Incontinência Pigmentar) é uma genodermatose rara, que afeta, principalmente, o sexo feminino, pois costuma ser letal em pacientes do sexo masculino intraútero. Caracteriza-se, principalmente, pelas manifestações dermatológicas, podendo também apresentar anomalias dentárias, oftalmológicas e neurológicas. As lesões cutâneas apresentam 4 fases distintas: vesiculosa, verrucosa, pigmentar e atrófica; que podem seguir uma sequência irregular, havendo até sobreposição das mesmas.

Bloch-Sulzberger syndrome (incontinentia pigmenti) is a rare genodermatosis that affects predominantly females, since it is generally lethal to male fetuses in utero. It is characterized principally by skin lesions, but may also involve dental, ophthalmological and neurological abnormalities. The skin lesions are present in four different phases: vesicular, verrucous, hyperpigmented and atrophic/hypopigmented. Their sequence is irregular and overlapping of stages is common.