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Diabetes is a global healthcare problem that affects more than 400 million people worldwide. Treatment for type 1 and 2 diabetes is expected by targeting adenosine monophosphate activated protein kinase, AMPK, a well-known master regulator of glucose. Many pharmaceutical companies have tried to identify AMPK activators but few direct AMPK activators with high potency for the ß2-AMPK isoform, which is important for glucose homeostasis, have been found. In addition, their chemical structure is limited to benzimidazole or indole derivatives bearing an aromatic substituent at the C5 position of the core structure. We describe herein our efforts to identify novel benzimidazole derivatives that directly activate the ß2-AMPK isoform. Our newly designed activator 14d bearing a 1-amino indanyl moiety at the C5 position of the core exhibited high in vitro potency and good pharmacokinetic profiles. A single oral dosing of 14d showed dose-dependent activation of AMPK and blood-glucose-lowering effects was observed in a diabetic animal model. In addition, chronic AMPK activation with 14d led to dose-dependent reduction in HbA1c of the animal model.
Assuntos
Proteínas Quinases Ativadas por AMP , Benzimidazóis , Animais , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Antinematódeos , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Modelos Animais de Doenças , Glucose , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologiaRESUMO
Calcitonin (CT) is a marker for both initial diagnosis and monitoring of patients with residual or recurrent medullary thyroid carcinoma (MTC). In Japan, serum CT had been measured by radioimmunoassay (RIA) until recently. Electrochemiluminescence immunoassay (ECLIA) became commercially available in 2014, and this technique is now the only method used to examine CT concentration. The purposes of this study were to investigate the correlations between the CT concentration measured with ECLIA (ECLIA-CT) and RIA (RIA-CT) and to explore the clinical characteristics of patients with elevated ECLIA-CT. CT concentrations of 348 sera samples from 334 patients with various thyroid disorders including nine MTC were measured using both assays. The correlation analysis revealed an excellent correlation between ECLIA-CT and RIA-CT among the cases with CT level >150 pg/mL by both assays (rs = 0.991, p < 0.001). However, 63% of all samples exhibited undetectable ECLIA-CT, while their RIA-CTs were measured between 15 and 152 pg/mL. The ECLIA-CTs in all patients who underwent total thyroidectomy for non-MTC showed low concentrations. High ECLIA-CT was observed in patients with MTC or pancreas neuroendocrine tumor. ECLIA-CT was also increased in 14 other male patients with non-MTC, including four with renal failure. Multivariate logistic regression analysis showed that male sex, negative TgAb, and lower estimated glomerular filtration rate were independent factors to predict detectable ECLIA-CT (≥0.500 pg/mL). These results indicate that ECLIA-CT correlates well with RIA-CT in higher range and is affected by sex, TgAb, and renal function.
Assuntos
Autoanticorpos/sangue , Calcitonina/análise , Carcinoma Neuroendócrino/diagnóstico , Nefropatias/sangue , Medições Luminescentes/métodos , Neoplasias da Glândula Tireoide/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/imunologia , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Calcitonina/sangue , Calcitonina/normas , Carcinoma Neuroendócrino/sangue , Carcinoma Neuroendócrino/complicações , Carcinoma Neuroendócrino/fisiopatologia , Criança , Estudos de Coortes , Feminino , Humanos , Imunoensaio/métodos , Imunoensaio/normas , Nefropatias/complicações , Nefropatias/fisiopatologia , Testes de Função Renal/normas , Medições Luminescentes/normas , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Radioimunoensaio/métodos , Radioimunoensaio/normas , Valores de Referência , Fatores Sexuais , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/fisiopatologia , Adulto JovemRESUMO
BACKGROUND: Retinoic acid receptor-related orphan receptor gamma t (RORγt) has critical roles in the development, maintenance and function of interleukin (IL)-17-producing cells and is a highly attractive target for the treatment of IL-17-mediated autoimmune disease, particularly psoriasis. On the other hand, RORγt is also critical for controlling apoptosis during thymopoiesis, and genetic RORγt ablation or systematic RORγt inhibition cause progressive thymic aberrations leading to T cell lymphomas. OBJECTIVE: We investigated whether topical administration of our novel RORγt inhibitor, S18-000003 has therapeutic potential for psoriasis with low risk of thymic aberrations. METHODS: We evaluated the effect of topical S18-000003 on psoriasis-like skin inflammation and influence on the thymus in a 12-O-tetradecanoylphorbol-13-acetate-induced K14.Stat3C mouse psoriasis model. RESULTS: S18-000003 markedly inhibited the development of psoriatic skin inflammation via suppression of the IL-17 pathway. In the skin, S18-000003 suppressed all subsets of IL-17-producing cells that we previously identified in this psoriasis model: Th17 cells, Tc17 cells, dermal γδ T cells, TCR- cells that probably included innate lymphoid cells, and CD4-CD8- double-negative αß T cells. Notably, neither reduction of CD4+CD8+ double-positive thymocytes nor dysregulation of cell cycling was observed in S18-000003-treated mice, even at a high dose. CONCLUSION: Our topically administered RORγt inhibitor is a potential therapeutic agent for psoriasis with low risk of thymic lymphoma.
Assuntos
Fármacos Dermatológicos/farmacologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Psoríase/tratamento farmacológico , Sulfonas/farmacologia , Administração Cutânea , Animais , Células Cultivadas , Fármacos Dermatológicos/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Voluntários Saudáveis , Humanos , Imunidade Inata/efeitos dos fármacos , Interleucina-17/imunologia , Interleucina-17/metabolismo , Leucócitos Mononucleares , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Cultura Primária de Células , Psoríase/diagnóstico , Psoríase/etiologia , Psoríase/patologia , Índice de Gravidade de Doença , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Sulfonas/uso terapêutico , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/imunologia , Acetato de Tetradecanoilforbol/toxicidade , Resultado do TratamentoRESUMO
Inhibitors of poly(ADP-ribose) polymerase (PARP) are new types of personalized treatment of relapsed platinum-sensitive ovarian cancer harboring BRCA1/2 mutations. Ovarian clear cell cancer (CCC), a subset of ovarian cancer, often appears as low-stage disease with a higher incidence among Japanese. Advanced CCC is highly aggressive with poor patient outcome. The aim of the present study was to determine the potential synthetic lethality gene pairs for PARP inhibitions in patients with CCC through virtual and biological screenings as well as clinical studies. We conducted a literature review for putative PARP sensitivity genes that are associated with the CCC pathophysiology. Previous studies identified a variety of putative target genes from several pathways associated with DNA damage repair, chromatin remodeling complex, PI3K-AKT-mTOR signaling, Notch signaling, cell cycle checkpoint signaling, BRCA-associated complex and Fanconi's anemia susceptibility genes that could be used as biomarkers or therapeutic targets for PARP inhibition. BRCA1/2, ATM, ATR, BARD1, CCNE1, CHEK1, CKS1B, DNMT1, ERBB2, FGFR2, MRE11A, MYC, NOTCH1 and PTEN were considered as candidate genes for synthetic lethality gene partners for PARP interactions. When considering the biological background underlying PARP inhibition, we hypothesized that PARP inhibitors would be a novel synthetic lethal therapeutic approach for CCC tumors harboring homologous recombination deficiency and activating oncogene mutations. The results showed that the majority of CCC tumors appear to have indicators of DNA repair dysfunction similar to those in BRCA-mutation carriers, suggesting the possible utility of PARP inhibitors in a subset of CCC.
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Mullerian adenosarcoma (MA) is a rare tumor variant with low malignancy potential and is reported to account for 8% of all uterine sarcomas. Cervical MAs are reported to occur in relatively younger patients with the mean age of 27 years, while those in the uterine corpus generally present in postmenopausal women. Due to the rarity of cervical MAs, optimal management for these patients (especially younger women) is still under exploration. Here, we describe a case of cervical MA in a woman of reproductive age who was treated by fertility-preserving surgery and successfully delivered a child 18 months later.
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The Sec translocon facilitates transportation of newly synthesized polypeptides from the cytoplasm to the lumen/periplasm across the phospholipid membrane. Although the polypeptide-conducting machinery is formed by the SecYEG-SecA complex in bacteria, its transportation efficiency is markedly enhanced by SecDF. A previous study suggested that SecDF assumes at least two conformations differing by a 120° rotation in the spatial orientation of the P1 head subdomain to the rigid base, and that the conformational dynamics plays a critical role in polypeptide translocation. Here we addressed this hypothesis by analyzing the 3D structure of SecDF using electron tomography and single particle reconstruction. Reconstruction of wt SecDF showed two major conformations; one resembles the crystal structure of full-length SecDF (F-form structure), while the other is similar to the hypothetical structural variant based on the crystal structure of the isolated P1 domain (I-form structure). The transmembrane domain of the I-form structure has a scissor like cleft open to the periplasmic side. We also report the structure of a double cysteine mutant designed to constrain SecDF to the I-form. This reconstruction has a protrusion at the periplasmic end that nicely fits the orientation of P1 in the I-from. These results provide firm evidence for the occurrence of the I-form in solution and support the proposed F- to I-transition of wt SecDF during polypeptide translocation.
Assuntos
Proteínas de Bactérias/ultraestrutura , Proteínas de Membrana/ultraestrutura , Proteínas de Membrana Transportadoras/ultraestrutura , Thermus thermophilus/genética , Proteínas de Bactérias/genética , Cristalografia por Raios X , Tomografia com Microscopia Eletrônica , Proteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Mutação , Estrutura Terciária de Proteína , Transporte ProteicoRESUMO
PURPOSE: An antiemetic regimen for patients taking paclitaxel and carboplatin (TC) includes dexamethasone (20 mg) to protect against hypersensitivity. Chemotherapy-induced nausea and vomiting (CINV), however, is difficult to adequately control in patients receiving TC. In the present study, we retrospectively investigated risk factors for CINV in patients receiving TC with this antiemetic regimen based on a questionnaire. METHODS: Eligible patients were diagnosed with gynecologic cancer and receiving paclitaxel (175 mg/m(2)) intravenously for 3 h and carboplatin (area under the curve 5 mg/mL per min) on day 1 every 3 weeks in our institution, and treated with granisetron (3 mg) and dexamethasone (20 mg) for antiemesis. Data of nausea and vomiting assessed by Common Terminology Criteria for Adverse Events version4.0 were collected from the medical records. Patients were asked to complete a questionnaire including items such as age and hyperemesis. Logistic regression analysis was used to evaluate univariate and independent multivariate associations with items on nausea of grade 2 or greater and vomiting of grade 1 or greater. RESULTS: On univariate logistic analysis, no item was significantly associated with nausea of grade 2 or greater. Hypertension and hyperemesis gravidarum and adjuvant chemotherapy were significantly associated with delayed vomiting of grade 1 or greater. Multivariate analysis was performed with delayed vomiting of grade 1 or greater as an endpoint, and the resulting independent items were hypertension and hyperemesis gravidarum. CONCLUSIONS: The present study showed that the risk factor for delayed vomiting of grade 1 or higher was a history of hyperemesis gravidarum in patients receiving conventional TC with dexamethasone (20 mg) and granisetron. Therefore, in patients with this risk factor, criteria of major organizations should be followed first.
Assuntos
Antineoplásicos/efeitos adversos , Carboplatina/efeitos adversos , Neoplasias dos Genitais Femininos/tratamento farmacológico , Náusea/induzido quimicamente , Paclitaxel/efeitos adversos , Vômito/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antieméticos/uso terapêutico , Antineoplásicos/administração & dosagem , Carboplatina/administração & dosagem , Dexametasona/uso terapêutico , Feminino , Granisetron/uso terapêutico , Humanos , Hiperêmese Gravídica/epidemiologia , Hipertensão/epidemiologia , Pessoa de Meia-Idade , Análise Multivariada , Náusea/tratamento farmacológico , Paclitaxel/administração & dosagem , Gravidez , Estudos Retrospectivos , Inquéritos e Questionários , Vômito/tratamento farmacológicoRESUMO
Endometriosis-associated ovarian cancers demonstrate substantial morphological and genetic diversity. The transcription factor, hepatocyte nuclear factor (HNF)-1ß, may be one of several key genes involved in the identity of ovarian clear cell carcinoma (CCC). The present study reviews a considerably expanded set of HNF-1ß-associated genes and proteins that determine the pathophysiology of CCC. The current literature was reviewed by searching MEDLINE/PubMed. Functional interpretations of gene expression profiling in CCC are provided. Several important CCC-related genes overlap with those known to be regulated by the upregulation of HNF-1ß expression, along with a lack of estrogen receptor (ER) expression. Furthermore, the genetic expression pattern in CCC resembles that of the Arias-Stella reaction, decidualization and placentation. HNF-1ß regulates a subset of progesterone target genes. HNF-1ß may also act as a modulator of female reproduction, playing a role in endometrial regeneration, differentiation, decidualization, glycogen synthesis, detoxification, cell cycle regulation, implantation, uterine receptivity and a successful pregnancy. In conclusion, the present study focused on reviewing the aberrant expression of CCC-specific genes and provided an update on the pathological implications and molecular functions of well-characterized CCC-specific genes.
RESUMO
Women with hereditary breast and ovarian cancer (HBOC) syndrome represent a unique group who are diagnosed at a younger age and result in an increased lifetime risk for developing breast, ovarian and other cancers. This review integrates recent progress and insights into the molecular basis that underlie the HBOC syndrome. A review of English language literature was performed by searching MEDLINE published between January 1994 and October 2012. Mutations and common sequence variants in the BRCA1 and BRCA2 (BRCA) genes are responsible for the majority of HBOC syndrome. Lifetime cancer risks in BRCA mutation carriers are 60-80% for breast cancer and 20-40% for ovarian cancer. Mutations in BRCA genes cannot account for all cases of HBOC, indicating that the remaining cases can be attributed to the involvement of constitutive epimutations or other cancer susceptibility genes, which include Fanconi anemia (FA) cluster (FANCD2, FANCA and FANCC), mismatch repair (MMR) cluster (MLH1, MSH2, PMS1, PMS2 and MSH6), DNA repair cluster (ATM, ATR and CHK1/2), and tumor suppressor cluster (TP53, SKT11 and PTEN). Sporadic breast cancers with TP53 mutations or epigenetic silencing (hypermethylation), ER- and PgR-negative status, an earlier age of onset and high tumor grade resemble phenotypically BRCA1 mutated cancers termed 'BRCAness', those with no BRCA mutations but with a dysfunction of the DNA repair system. In conclusion, genetic or epigenetic loss-of-function mutations of genes that are known to be involved in the repair of DNA damage may lead to increased risk of developing a broad spectrum of breast and ovarian cancers.
Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Feminino , HumanosRESUMO
OBJECTIVE: In the present study, we evaluated changes in CA-125 cut-off values predictive of complete interval debulking surgery (IDS) after neoadjuvant chemotherapy (NAC) using receiver operating characteristic (ROC) analysis. METHODS: This retrospective single-institution study included patients with International Federation of Gynecology and Obstetrics (FIGO) stage III epithelial ovarian cancer and a pre-NAC serum CA-125 level of greater than 40 U/mL who were treated with neoadjuvant platinum-based chemotherapy followed by IDS between 1994 and 2009. Logistic regression analysis was used to evaluate univariate and independent multivariate associations with the effect of clinical, pathological, and CA-125 parameters on complete IDS, and ROC analysis was used to determine potential cut-off values of CA-125 for prediction of the possibility of complete IDS. RESULTS: Seventy-five patients were identified. Complete IDS was achieved in 46 (61.3%) patients and non-complete IDS was observed 29 (38.7%). Median pre-NAC CA-125 level was 639 U/mL (range, 57 to 6,539 U/mL) in the complete IDS group and 1,427 U/mL (range, 45 to 10,989 U/mL) in the non-complete IDS group. Median pre-IDS CA-125 level was 15 U/mL (range, 2 to 60 U/mL) in the complete IDS group and 53 U/mL (range, 5 to 980 U/mL) in the non-complete IDS group (p<0.001). Multivariate analyses performed with complete IDS as the endpoint revealed only pre-IDS CA-125 as an independent predictor. The odds ratio of non-complete IDS was 10.861 when the pre-IDS CA-125 level was greater than 20 U/mL. CONCLUSION: The present data suggest that in the setting of IDS after platinum-based NAC for advanced ovarian cancer, a pre-IDS CA-125 level less than 20 U/mL is an independent predictor of complete IDS.
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The total synthesis of a systematic series of vinblastine analogues that contain deep-seated structural modifications to the core ring system of the lower vindoline subunit is described. Complementary to the vindoline 6,5 DE ring system, compounds with 5,5, 6,6, and the reversed 5,6 membered DE ring systems were prepared. Both the natural cis and unnatural trans 6,6-membered ring systems proved accessible, with the latter representing a surprisingly effective class for analogue design. Following Fe(III)-promoted coupling with catharanthine and in situ oxidation to provide the corresponding vinblastine analogues, their evaluation provided unanticipated insights into how the structure of the vindoline subunit contributes to activity. Two potent analogues (81 and 44) possessing two different unprecedented modifications to the vindoline subunit core architecture were discovered that matched the potency of the comparison natural products and both lack the 6,7-double bond whose removal in vinblastine leads to a 100-fold drop in activity.
Assuntos
Antineoplásicos Fitogênicos/química , Vimblastina/análogos & derivados , Antineoplásicos Fitogênicos/síntese química , Avaliação Pré-Clínica de Medicamentos , Vimblastina/síntese química , Vimblastina/químicaRESUMO
The characteristics of de novo diffuse large B-cell lymphoma (DLBCL) with translocation of c-myc and immunoglobulin (Ig) genes (c-myc/Ig DLBCL), were investigated in 13 cases of c-myc/Ig DLBCL. Immunohistochemistry revealed five cases were positive for CD10 and BCL6 expression (CD10(+)/BCL6(+)), five cases of CD10(-)/BCL6(+)/MUM1(-), one case of CD10(-)/BCL6(+)/MUM1(+) and two cases of CD10(-)/BCL6(-)/MUM1(+) expression, indicating 10 cases of germinal center B-cell DLBCL and three cases of non-germinal center B-cell DLBCL. Ongoing mutation of the Ig heavy chain gene variable region (IgH-V) was found in two cases with CD10 and BCL6 expression and one case showing CD10(-)/BCL6(+)/MUM1(-) expression. These three cases of ongoing mutation of the IgH-V gene did not express BCL2, unlike those without ongoing mutation. These results suggest a heterogeneous immunophenotype and genotype for c-myc/Ig DLBCL, with CD10(-)/BCL6(+)/MUM1(-) cases the most frequent.
Assuntos
Genes de Imunoglobulinas , Genes myc , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Linfoma Difuso de Grandes Células B/genética , Translocação Genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Ligação a DNA/metabolismo , Feminino , Genótipo , Humanos , Imuno-Histoquímica , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Mutação , Neprilisina/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6RESUMO
CD5+ diffuse large B-cell lymphoma (DLBCL) has recently been identified as a subgroup with different clinical characteristics from CD5- DLBCL and as having a poorer outcome than CD5- DLBCL. Data regarding differences in gene alteration between CD5+ and CD5- DLBCL have accumulated. In this article, we report an analysis of the immunoglobulin heavy-chain gene variable region (VH) gene in 35 cases of CD5+ DLBCL and compare these cases with those with the germline of the VH gene (GL-VH) and those with a somatically hypermutated VH gene (HM-VH). When the CD5+ DLBCL cases were subdivided with a cutoff value of 98% homology in the VH gene, there were 7 cases (20%) of GL-VH and 28 cases (80%) of HM-VH. The proportion of GL-VH cases in CD5+ DLBCL was more than that in CD5 DLBCL. Although we found no significant difference in pretreatment clinical parameters between the GL-VH and HM-VH subgroups, there was a tendency for the GL-VH subgroup to show lower incidences of elevation of lactate dehydrogenase and >1 site of extranodal involvement compared to the HM-VH subgroup. The overall survival curve of the HM-VH subgroup showed a rapid decline followed by a plateau, whereas that of the GL-VH subgroup declined constantly after 5 years, suggesting that GL-VH disease may not be curable by standard therapies. These findings suggest that CD5+ DLBCL with GL-VH shares clinical features with mantle cell lymphoma, the cellular origin of which has been considered to be pre-germinal center B-cells. We therefore propose that analysis of the VH gene is important for predicting the clinical course of CD5+ DLBCL.
Assuntos
Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Linfoma de Células B/genética , Linfoma Difuso de Grandes Células B/genética , Antígenos CD5/metabolismo , Mutação em Linhagem Germinativa , Centro Germinativo/patologia , Humanos , Linfoma de Células B/imunologia , Linfoma de Células B/mortalidade , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/mortalidade , Hipermutação Somática de ImunoglobulinaRESUMO
Primary breast diffuse large B-cell lymphoma has a poor prognosis relative to other extranodal diffuse large B-cell lymphoma. Recently, diffuse large B-cell lymphoma has been subclassified as germinal center B-cell-like and nongerminal center B-cell types using tissue microarrays. The 5-year overall survival rate of the germinal center B-cell group is better than that of the nongerminal center B-cell group. To elucidate the reason for which primary breast diffuse large B-cell lymphoma has a poor clinical outcome, we investigated 15 patients with primary breast diffuse large B-cell lymphoma (stage IE; 13 cases, stage IIE; two cases) by immunohistochemistry using various markers including CD10, Bcl-6, MUM1 and MIB-1 and by molecular analysis of the immunoglobulin heavy chain gene variable region. Immunohistochemistry showed 0/15 (positive cases/examined cases) for CD10, 5/15 for Bcl-6, 15/15 for MUM1, 10/15 for Bcl-2, 2/15 for CD5 and 4/15 for CD40. The expression pattern of CD10(-) MUM1(+) in primary breast diffuse large B-cell lymphoma corresponded to the nongerminal center B-cell group. Moreover, the MIB-1 index was distributed from 60 to 95% with a mean of 79%, indicating a high proliferation of the lymphoma cells. The immunoglobulin heavy chain gene variable region of primary breast diffuse large B-cell lymphoma had a mutation frequency of 1-10% (seven cases) and 0-1 additional mutations in ongoing mutation analysis (five cases). Primary breast diffuse large B-cell lymphoma had characteristics of the nongerminal center B-cell group. In conclusion, primary breast diffuse large B-cell lymphoma has a nongerminal center B-cell phenotype and has a high MIB-1 index. These features might therefore be associated with poor prognosis.
Assuntos
Linfócitos B/patologia , Neoplasias da Mama/patologia , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/patologia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD20/análise , Linfócitos B/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Antígenos CD40/análise , Proteínas de Ligação a DNA/análise , Feminino , Centro Germinativo/patologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Imuno-Histoquímica , Fatores Reguladores de Interferon , Antígeno Ki-67/análise , Linfoma de Células B/genética , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Pessoa de Meia-Idade , Mutação , Fenótipo , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-6 , Fatores de Transcrição/análiseRESUMO
Somatic mutation (SM) analysis provides a useful tool for understanding the stages at which neoplastic differentiate from normal B-cells. B-cell precursor neoplasms are considered to be somatically premutational. However, the variable frequency of SM of the variable region (VH) genes has been described in cases of precursor B-cell acute lymphoblastic leukemia (PB-ALL). To better characterize PB-ALL based on the differentiation stage, we investigated the SM of the VH genes expressed by tumor cells of the surface immunoglobulin (sIg)(-) HBL-3 cell line derived from childhood PB-ALL. In the HBL-3 cell line, the rearranged Ig heavy chain VH gene sequence showed no SM in the complementarity-determining regions of 1, 2, and 3, or in the framework regions of 1, 2, and 3 relative to the putative germline VH gene sequences. In addition, the VH segment of HBL-3 cells showed no intraclonal sequence heterogeneity, indicating ongoing SM. Our data demonstrated that HBL-3 cells express unmutated and developmentally regulated rearrangement of VH genes at the stage of B-cell precursor cells. HBL-3 cells, which are derived only from the sIg(-) PB-ALL, showed that SM cannot be recognized in VH genes of tumor cells before the expression of sIg.
Assuntos
Linfoma de Burkitt/genética , Regulação Neoplásica da Expressão Gênica , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Hipermutação Somática de Imunoglobulina/genética , Sequência de Bases , Biomarcadores Tumorais/análise , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Análise Mutacional de DNA , Primers do DNA/química , DNA de Neoplasias/análise , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Reação em Cadeia da PolimeraseRESUMO
CD10, a proteolytic enzyme seen in germinal center cells and in the majority of follicular lymphomas, is occasionally expressed in diffuse large B-cell lymphomas (DLBCL). To clarify the origin and cellular characteristics of CD10-positive DLBCL, we analyzed 36 de novo cases of DLBCL for somatic mutations of the immunoglobulin heavy chain variable region (VH) genes and for their immunophenotypes. Expression greater than that of grade 2 Bcl-6 was observed in 11 of the 30 CD10-negative cases (37%) and in all six CD10-positive cases (100%; P < 0.05) without expression of CD5, CD23, cyclin D1, CD30 or CD138. The average mutation frequencies of the six CD10-positive and 30 CD10-negative DLBCL were 12.9 and 9.8%, respectively. The range of SM frequencies in CD10-positive DLBCL (9.52-18.06) was distinctly narrower than that observed for CD10-negative DLBCL (0.69-26.89). These findings seem to indicate that CD10-positive DLBCL, originating from germinal center B cells, is a genetically and immunophenotypically more homogeneous group than CD10-negative DLBCL. Furthermore, three extranodal lymphomas, in five of the six CD10-positive DLBCL, showed ongoing mutation, indicating that antigen-driven, high-affinity somatic mutation may play an important role in clonal expansion in CD10-positive DLBCL. All four extranodal cases of the six CD10-positive DLBCL showed ongoing mutation and/or bcl-2/JH rearrangement. This result suggests that the cell origin of extranodal CD10-positive DLBCL may be the same as that of follicular lymphomas.
Assuntos
Genes de Imunoglobulinas , Região Variável de Imunoglobulina/genética , Linfoma de Células B/genética , Linfoma Difuso de Grandes Células B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Feminino , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Imuno-Histoquímica , Imunofenotipagem , Linfoma de Células B/imunologia , Linfoma Difuso de Grandes Células B/imunologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação/genética , Neprilisina/metabolismoRESUMO
We examined nucleotide sequences of Epstein-Barr virus (EBV)-positive Hodgkin/Reed-Sternberg (HRS)-like B cells in a case of diffuse large B-cell lymphoma (DLBCL) and a case of adult T-cell lymphoma (ATL) for single-cell polymerase chain reaction of the immunoglobulin heavy-chain gene variable region (VH gene). HRS-like B cells were scattered in the area irrelevant to the lymphoma infiltrates of DLBCL and in the lymphoma area of ATL. HRS-like B cells were positive for CD20 and CD30 but negative for CD15. EBV presented in HRS-like B cells in both cases but not in any lymphoma cells. VH genes of five HRS-like B cells analyzed in DLBCL were polyclonal and showed in-frame sequences with 0% to 2.8% somatic mutation frequency. In an ATL, VH genes of five HRS-like B cells analyzed were polyclonal and somatically mutated. Four cells carried in-frame rearrangements with 3.5% to 17.7% mutation frequency. One of the VH genes has a one-codon deletion. From the fifth cell, an out-of-frame rearrangement with an insertion and a deletion was obtained. Thus, we showed polyclonal EBV-positive HRS-like B cells in both DLBCL and ATL and that whereas EBV-positive, HRS-like B cells in DLBCL exhibited unmutated and mutated VH gene, those in ATL were found to have a somatically mutated VH gene with/without deletions and/or insertions. The HRS-like B cells may appear because of active EBV infection in a patient who is immunosuppressed from the primary lymphoma.