RESUMO
Lymphomas represent one of the most frequent cancer types in Africa. In particular, approximately 30,000 non-Hodgkin lymphomas occur in the equatorial belt of Africa each year and these tumours are in among the top-ten cancers in this geographical region. Several pathogens and environmental factors have been detected in association with these tumours, suggesting that they may contribute to lymphomagenesis. Unfortunately, there are still striking differences between developed and African countries in terms of early detection, diagnosis and treatment of lymphomas. Of note, the disease burden appears to be increasing in Africa. In addition, a much lower cure rate in the low-income countries suggests that the difference in mortality will even become more pronounced in future. Therefore, improving diagnosis is crucial as without it, neither meaningful research projects nor effective patient management can be instituted. In this review, we will summarize the state-of-the-art of lymphoma epidemiology, pathobiology and therapy, and will highlight the still existing gaps between developed and African countries.
Assuntos
Linfoma/epidemiologia , África/epidemiologia , Feminino , Humanos , Linfoma/patologia , Masculino , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate the efficacy of visual inspection with acetic acid (VIA) screening combined with a cervical smear in Uganda. METHODS: Nine screening campaigns were held in Uganda between January 2011 and October 2019. In the last three campaigns, a new approach was used: the cervical smear was performed before the VIA test and, in case of a positive VIA test, the slide was sent for examination. The data collected were divided into two groups: the first six campaigns and the last three campaigns. RESULTS: During the study period, 10 520 women were screened, of whom 911 had a positive VIA test. The VIA test showed 84.2% false positives. In the first group, the VIA test was positive in 516 women, of whom 93% were referred for further examinations. In the second group, the VIA test was positive in 395 women, but the cervical smear was positive in only 65 women. Thus, only 16.5% women were referred for further examinations. CONCLUSION: Combining cervical smear, VIA test, and slide analysis in positive VIA tests may allow women who need treatment to be selected more effectively, while waiting for other more expensive solutions to become more affordable for this setting.
Assuntos
Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/prevenção & controle , Exame Físico , Displasia do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , Esfregaço Vaginal , Ácido Acético , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Promoção da Saúde , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Infecções por Papillomavirus/diagnóstico , Uganda , Neoplasias do Colo do Útero/diagnóstico , Adulto Jovem , Displasia do Colo do Útero/diagnósticoRESUMO
Endemic, sporadic and HIV-associated Burkitt lymphoma (BL) all have a B-cell phenotype and a MYC translocation, but a variable association with the Epstein-Barr virus (EBV). However, there is still no satisfactory explanation of how EBV participates in the pathogenesis of BL. A recent investigation suggested that EBV-positive and EBV-negative BL have different cells of origin. In particular, according to immunoglobulin gene mutation analysis, EBV-negative BLs may originate from early centroblasts, whereas EBV-positive BLs seem to arise from postgerminal center B cells or memory B cells. The appearance of a germinal center phenotype in EBV-positive cells might thus derive from a block in B-cell differentiation. The exit from the germinal center involves a complex series of events, which require the activation of BLIMP-1, and the consequent downregulation of several target genes. Here, we investigated the expression of specific miRNAs predicted to be involved in B-cell differentiation and found that hsa-miR-127 is differentially expressed between EBV-positive and EBV-negative BLs. In particular, it was strongly upregulated only in EBV-positive BL samples, whereas EBV-negative cases showed levels of expression similar to normal controls, including microdissected germinal centers (GC) cells. In addition, we found evidence that hsa-miR-127 is involved in B-cell differentiation process through posttranscriptional regulation of BLIMP1 and XBP1. The overexpression of this miRNA may thus represent a key event in the lymphomagenesis of EBV positive BL, by blocking the B-cell differentiation process.
Assuntos
Linfócitos B/metabolismo , Linfoma de Burkitt/genética , Diferenciação Celular , MicroRNAs/genética , Processamento Pós-Transcricional do RNA , Adolescente , Adulto , Linfócitos B/patologia , Linfócitos B/virologia , Western Blotting , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Criança , Pré-Escolar , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Herpesvirus Humano 4/crescimento & desenvolvimento , Humanos , Masculino , Pessoa de Meia-Idade , Fator 1 de Ligação ao Domínio I Regulador Positivo , Fatores de Transcrição de Fator Regulador X , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína 1 de Ligação a X-Box , Adulto JovemRESUMO
Vascular Endothelial Growth Factor (VEGF)-D is a member of the VEGF family of angiogenic growth factors that activate the Vascular Endothelial Growth Factor Receptor (VEGFR)-2 and VEGFR-3, which are mainly expressed in blood and lymphatic vessels. Here we have analyzed by using monoclonal antibodies, the expression of VEGF-D and its cognate receptor VEGFR-3 in normal and pathologic bone marrow and lymph node biopsies. This analysis revealed that VEGF-D is expressed in B cells of the germinal centers, scattered B and T blasts, myeloid progenitors, acute leukemia, several types of non Hodgkin lymphoma, and classical Hodgkin's lymphoma. In normal tissues VEGFR-3 was only expressed in fenestrated capillaries of bone marrow and in lymphatic vessels of lymph nodes, while in VEGF-D expressing tumors newly formed vessels, but not malignant cells, showed high VEGFR-3 expression. These data suggest that VEGF-D could contribute to leukemia and lymphoma growth via the induction of angiogenesis in bone marrow and lymphoid tissues.
Assuntos
Regulação Leucêmica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Linfócitos/metabolismo , Fator D de Crescimento do Endotélio Vascular/biossíntese , Anticorpos Monoclonais/química , Biópsia , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Células HL-60 , Humanos , Células K562 , Linfonodos/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Mature cystic teratoma (dermoid cyst) is the most common benign germ cell tumor of the ovary, accounting for approximately 30% of all ovarian tumors. Malignant transformation is rare; the most frequent transformation reported is to squamous-cell carcinoma in 80% of cases, whereas transformation to adenocarcinoma is described in about 7% of cases. We report a case of malignant transformation to mucinous adenocarcinoma arising from respiratory-like epithelium in a mature teratoma of the ovary.
Assuntos
Adenocarcinoma Mucinoso/patologia , Transformação Celular Neoplásica , Neoplasias Ovarianas/patologia , Mucosa Respiratória/patologia , Teratoma/patologia , Idoso , Coristoma/patologia , Cisto Dermoide/patologia , Feminino , HumanosRESUMO
OBJECTIVE: To test CD-34 immunoreactivity in stromal cornea cells in normal and pathologic samples obtained from penetrating keratoplasty. DESIGN: Prospective, consecutive histopathologic human tissue study. PARTICIPANTS AND CONTROLS: One hundred two cornea buttons from patients with different diseases, submitted for cornea transplant, were examined. Controls were expired corneas from healthy donor patients who died (n = 4), and globes enucleated for primitive intraocular neoplasias, that is, retinoblastomas (n = 8), and malignant choroidal melanomas (n = 2). METHODS: The expression of CD-34 in stromal cornea cells was examined by immunohistochemistry analysis. Other immunohistochemical stains included an endothelial cell marker (CD-31), common leukocyte antigen, and alpha-smooth muscle actin. MAIN OUTCOME MEASURES: Different diseases that may cause blindness and require penetrating keratoplasty have been tested for CD-34 immunoreactivity. RESULTS: In control corneas, keratocytes present strong and consistent CD-34 immunoreactivity. Diseases leading to the loss of transparency and penetrating keratoplasty, such as keratoconus, herpes keratitis, trauma, and heredofamilial dystrophies, are associated with focal or diffuse loss of CD-34 expression, whereas pseudophakic bullous keratopathy and Fuchs' endothelial dystrophy show normal CD-34 immunoreactivity in most cases and patchy unstained stromal areas in a few cases. CONCLUSIONS: Scar tissue formation in the cornea, as in herpes keratitis and trauma, is always associated with loss of CD-34 immunoreactivity, which may otherwise be a primary event in keratoconus and heredofamilial dystrophies. Both in the pseudophakic bullous keratopathy and Fuchs' endothelial dystrophy, CD-34 immunoreactivity may be normal or lost, hence these two diseases may be considered as one and part of the same group with regard to CD-34 expression, as revealed by immunohistochemistry analysis.
Assuntos
Antígenos CD34/metabolismo , Doenças da Córnea/metabolismo , Substância Própria/metabolismo , Actinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças da Córnea/cirurgia , Feminino , Antígenos HLA/metabolismo , Humanos , Técnicas Imunoenzimáticas , Ceratoplastia Penetrante , Masculino , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismoRESUMO
BACKGROUND: Solitary fibrous tumor (SFT) is a rare spindle cell tumor that arises most often in the visceral pleura; however, a review of the literature shows at least 31 cases occurring in the orbit. METHODS: A retrospective case series of three patients with orbital SFT: a 50-year-old man, observed in 1997, with an angioma-like lesion in the upper half of the orbit causing osteolysis of the orbital roof; a 24-year-old man, observed in 1992, with a superotemporal mass in the right orbit occupying the lacrimal gland region, firstly diagnosed as schwannoma, recurring 4 years after dacryoadenectomy; a 70-year-old man, with a retrobulbar mass diagnosed on a biopsy as hemangiopericytoma, recurring and infiltrating the orbital roof 4 years after surgery. RESULTS: A review of the literature and presentation of three cases of SFT which showed infiltration of the orbital roof and/or recurrence. CONCLUSIONS: Our cases provide evidence of how orbital SFT can behave aggressively and mimic other orbital tumors, thus making mandatory the consideration of this relatively new entity in common clinical practice as well as careful follow-up. Their aggressive growth is unusual, described in only 6 of the 31 cases so far reported in the literature. Immunohistochemistry is of importance for the diagnosis, since CD34 immunoreactivity is peculiar to SFT.
Assuntos
Fibroma/patologia , Neoplasias Orbitárias/patologia , Adulto , Idoso , Antígenos CD34/metabolismo , Biomarcadores Tumorais/metabolismo , Diagnóstico Diferencial , Fibroma/diagnóstico por imagem , Fibroma/metabolismo , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias Orbitárias/metabolismo , Radiografia , Estudos RetrospectivosRESUMO
BACKGROUND: Benign lymphoepithelial lesions (BLEL) are usually found in salivary glands in autoimmune disorders. Some LEL are recognized to already be, or may progress to become, lymphomas. Skin lesions similar to LEL have been described in lymphomas, and are caused by neoplastic lymphocytes which infiltrate adnexal structures. To date, BLEL have not widely been recognized in the skin. METHODS: We describe skin lesions similar to BLELs, at the periphery of squamous cell carcinomas (SCC) in 8 healthy patients, in one of whom the lesion recurred. Immunocharacterization of both epithelial and lymphocytic components and molecular genetic investigation was performed. Polymerase chain reaction (PCR) analysis was done to detect IgH chain gene, and T-cell receptor beta and gamma gene rearrangements. Association with Epstein-Barr virus (EBV) was also tested by in situ hybridization (ISH) for EBV-encoded RNAs (EBERs). RESULTS: Epithelial cells showed the immunophenotype of eccrine sweat gland ducts. Infiltrating lymphocytes expressed overwhelming B antigens and CD5. Neither clonal B and/or T proliferations nor EBERs signals were demonstrable. CONCLUSIONS: We observed skin lesions similar to BLELs, showing modifications of sweat gland duct and CD5+, B lymphocytic expansion. In our cases there were no associated autoimmune disorders; the local immunoresponse to SCC might have caused BLEL.
Assuntos
Carcinoma de Células Escamosas/patologia , Tecido Linfoide/patologia , Transtornos Linfoproliferativos/patologia , Neoplasias Cutâneas/patologia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Antígenos CD5/metabolismo , Antígenos CD79 , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , DNA de Neoplasias/análise , Glândulas Écrinas/metabolismo , Glândulas Écrinas/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Humanos , Tecido Linfoide/metabolismo , Transtornos Linfoproliferativos/complicações , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos B/metabolismo , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismoRESUMO
CDK9 is a member of the CDC2-like family of kinases. Its cyclin partners are members of the CYCLIN T family (T1, T2a, and T2b) and CYCLIN K. The CDK9/CYCLIN T1 complex is very important in the differentiation programme of several cell types, controlling specific differentiation pathways. Limited data are available regarding the expression of CDK9/CYCLIN T1 in haematopoietic and lymphoid tissues. The aim of this study was to analyse the expression of the CDK9/CYCLIN T1 complex in lymphoid tissue, in order to assess its role in B- and T-cell differentiation and lymphomagenesis. CDK9/CYCLIN T1 expression was found by immunohistochemistry in precursor B and T cells. In peripheral lymphoid tissues, germinal centre cells and scattered B- and T-cell blasts in interfollicular areas expressed CDK9/CYCLIN T1, while mantle cells, plasma cells, and small resting T-lymphocytes displayed no expression of either molecule. CDK9/CYCLIN T1 expression therefore appears to be related to particular stages of lymphoid differentiation/activation. CDK9 and CYCLIN T1 were highly expressed in lymphomas derived from precursor B and T cells, from germinal centre cells, such as follicular lymphomas, and from activated T cells (ie anaplastic large cell lymphomas). Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma also showed strong nuclear staining. Diffuse large B-cell, Burkitt's lymphomas, and peripheral T-cell lymphomas, among T-cell lymphoproliferative disorders, showed a wide range of values. No expression of CDK9 or CYCLIN T1 was detected in mantle cell and marginal zone lymphomas. However, at the mRNA level, an imbalance in the CDK9/CYCLIN T1 ratio was found in follicular lymphoma and diffuse large B-cell lymphomas with germinal centre phenotype, and in the cell lines of classical Hodgkin's lymphomas, Burkitt's lymphomas, and anaplastic large cell lymphoma, in comparison with reactive lymph nodes. These results suggest that the CDK9/CYCLIN T1 complex may affect the activation and differentiation programme of lymphoid cells. The molecular mechanism through which the CDK9/CYCLIN T1 complex is altered in malignant transformation needs to be elucidated.