Linfoma burkitt-like em um lactente: relato de caso

Os linfomas não Hodgkin da infância, incluindo os linfomas de Burkitt e Burkitt-like são raros em lactentes. Um caso de linfoma não Hodgkin B em uma lactente de 13 meses de idade é descrito. Ao diagnóstico a paciente apresentava extenso comprometimento abdominal associado à ascite, derrame pleural e síndrome de lise tumoral. A análise imunofenotípica mostrou um fenótipo compatível com células linfóides oriundas do centro germinativo e a origem clonal dessas células foi demonstrada por reação em cadeia da polimerase. Não foi demonstrada associação do linfoma com infecção pelo vírus Epstein-Barr e/ou virus da imunodeficiência adquirida. O caso apresentado enfatiza a necessidade de considerar o diagnóstico de linfoma mesmo em lactentes.Childhood non-Hodgkin's lymphomas, including Burkitt and Burkitt-like, are rarely diagnosed in infants. A case of B-cell lymphoma in a 13-month-old girl with extensive abdominal disease, ascites, pleural effusion, and tumor lysis syndrome is reported. Phenotypic analysis showed a germinal center B-cell phenotype, and a B-cell clonality was confirmed by polymerase chain reaction. There was no evidence of Epstein-Barr and HIV infection. The case herein reported emphasizes the need for considering the diagnosis of lymphoma even in very young children

XIAP and P-glycoprotein co-expression is related to imatinib resistance in chronic myeloid leukemia cells

AbstractP-glycoprotein (Pgp) and XIAP co-expression has been discussed in the process of the acquisition of multidrug resistance (MDR) in cancer. Here, we evaluated XIAP and Pgp expression in chronic myeloid leukemia (CML) samples, showing a positive correlation between them. Furthermore, we evaluated the effects of imatinib in XIAP and Pgp expression using CML cell lines K562 (Pgp−) and K562-Lucena (Pgp+). Imatinib increased XIAP and Pgp expression in K562-Lucena cells, while in K562 cells a downregulation of these proteins was observed, suggesting that imatinib induces an increment of MDR phenotype of CML cells that previously exhibit high levels of Pgp/XIAP co-expression

FOXK2 Transcription Factor and Its Emerging Roles in Cancer

Forkhead box (FOX) transcription factors compose a large family of regulators of key biological processes within a cell. FOXK2 is a member of FOX family, whose biological functions remain relatively unexplored, despite its description in the early nineties. More recently, growing evidence has been pointing towards a role of FOXK2 in cancer, which is likely to be context-dependent and tumour-specific. Here, we provide an overview of important aspects concerning the mechanisms of regulation of FOXK2 expression and function, as well as its complex interactions at the chromatin level, which orchestrate how it differentially regulates the expression of gene targets in pathophysiology. Particularly, we explore the emerging functions of FOXK2 as a regulator of a broad range of cancer features, such as cell proliferation and survival, DNA damage, metabolism, migration, invasion and metastasis. Finally, we discuss the prognostic value of assessing FOXK2 expression in cancer patients and how it can be potentially targeted for future anticancer interventions

p53 gene analysis in childhood B non - Hodgkin's lymphoma

CONTEXTO: Alterações do gene supressor de tumor p53, como mutações e deleções, são lesões genéticas encontradas com maior freqüência nas neoplasias humanas, incluindo câncer de mama, pulmão e cólon. Entre as malignidades hematológicas, o gene 53 é freqüentemente mutado no linfoma de Burkitt, sendo detectadas mutações em 30-40% das amostras tumorais e em 70% das linhagens celulares. OBJETIVO: Analisar as alterações do gene p53 em crianças com linfoma não-Hodgkin de origem B. TIPO DE ESTUDO: Estudo descritivo. LOCAL: Centro de Oncologia Terciário. PARTICIPANTES: O estudo analisou 12 pacientes com linfoma não-Hodgkin B classificados como linfoma de Burkitt. A análise de possíveis mutações do gene p53 foi realizada pela técnica de PCR-SSCP dos exons 5, 6 ,7 e 8/9 do gene. RESULTADOS: Um padrão anormal de migração foi observado em quatro pacientes (33.3%), em um paciente no exon 6 e em três no exon 7. Os casos positivos incluíam dois pacientes que evoluíram para o óbito por progressão da doença. CONCLUSÃO: Esses resultados preliminares sugerem que as alterações do gene p53 são freqüentes em crianças com linfoma de Burkitt e podem contribuir para patogênese ou progressão da doença.CONTEXT: Mutations or deletions in the tumor-suppressor gene p53 are among the commonest genetic changes found in human neoplasms including breast, lung and bowel cancers. In hematological malignancies, p53 is most often mutated in Burkitt's lymphoma, with p53 mutations present in 30 to 40% of tumor samples and in 70% of cell lines. OBJECTIVE: To analyze the p53 gene alterations in child patients with B non-Hodgkin's lymphoma. DESIGN: Descriptive study. SETTING: Tertiary oncology care center. PARTICIPANTS: The study investigated 12 patients with childhood B non-Hodgkin's lymphoma (Burkitt's lymphoma). Screening for p53 mutations was done by polymerase chain reaction - single strand conformational polymorphism (PCR-SSCP) analysis of exon 5 to 8/9 of the gene. RESULTS: Abnormal polymerase chain reaction - single strand conformational polymorphism migration pattern was observed in 4 patients (33.3%), one on exon 6 and three on exon 7. Positive cases included 2 patients who died from disease. CONCLUSION: These preliminary results suggest that p53 mutations are quite frequent in children with Burkitt's lymphoma and may play a role in lymphoma genesis or disease progression

p53 gene analysis in childhood B non - Hodgkin's lymphoma

CONTEXT: Mutations or deletions in the tumor-suppressor gene p53 are among the commonest genetic changes found in human neoplasms including breast, lung and bowel cancers. In hematological malignancies, p53 is most often mutated in Burkitt's lymphoma, with p53 mutations present in 30 to 40% of tumor samples and in 70% of cell lines. OBJECTIVE: To analyze the p53 gene alterations in child patients with B non-Hodgkin's lymphoma. DESIGN: Descriptive study. SETTING: Tertiary oncology care center. PARTICIPANTS: The study investigated 12 patients with childhood B non-Hodgkin's lymphoma (Burkitt's lymphoma). Screening for p53 mutations was done by polymerase chain reaction - single strand conformational polymorphism (PCR-SSCP) analysis of exon 5 to 8/9 of the gene. RESULTS: Abnormal polymerase chain reaction - single strand conformational polymorphism migration pattern was observed in 4 patients (33.3%), one on exon 6 and three on exon 7. Positive cases included 2 patients who died from disease. CONCLUSION: These preliminary results suggest that p53 mutations are quite frequent in children with Burkitt's lymphoma and may play a role in lymphoma genesis or disease progression

Primary colorectal diffuse large B-cell lymphoma: A report of eighteen cases in a tertiary care center

Primary colorectal diffuse large B-cell lymphoma (DLBCL) is very rare colon malignancy. It is important to know the main demographic and clinical characteristics of these patients. We conducted a retrospective analysis of 18 patients diagnosed with primary colorectal DLBCL during a 17-year period at the National Cancer Institute of Brazil (INCA) between 2000 and 2018. Demographic characteristics, tumor localization, HIV status, lactate dehydrogenase (LDH) levels, treatment modality and follow-up status were obtained from medical records. Survival was estimated from the date of diagnosis until death. There were 11 male and seven female patients in our cohort, the median age at diagnosis was 59.5 years and four patients were HIV positive. Tumor was mainly localized in the right colon. Patients were treated with chemotherapy (CT) and/or surgical resection. Eleven patients died during a median follow-up of 59 months and the median survival time was 10 months. Six or more cycles of CT (HR=0.19; CI 95% 0.054–0.660, p = 0.009), LDH levels below 350 U/L (HR=0.229; CI 95% 0.060–0.876, p = 0.031) and surgical resection (HR=0.23; CI 95% 0.065–0.828, p = 0.030) were associated with reduced risk of death in univariate analysis. Patient's age and DLBCL right colon localization should be considered at diagnosis to distinguish between DLBCL and other diseases for differential diagnosis. Six cycles of CT, LDH levels below 350 U/L and surgical resection were associated with better survival. Our results are consistent with previous publications and address the importance of correct colorectal DLBCL diagnosis and treatment