RESUMO
Humans are constantly exposed to a multitude of environmental chemicals that may disturb endocrine functions. It is crucial to identify such chemicals and uncover their mode-of-action to avoid adverse health effects. 11ß-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) catalyze the formation of cortisol and aldosterone, respectively, in the adrenal cortex. Disruption of their synthesis by exogenous chemicals can contribute to cardio-metabolic diseases, chronic kidney disease, osteoporosis, and immune-related disorders. This study applied in silico screening and in vitro evaluation for the discovery of xenobiotics inhibiting CYP11B1 and CYP11B2. Several databases comprising environmentally relevant pollutants, chemicals in body care products, food additives and drugs were virtually screened using CYP11B1 and CYP11B2 pharmacophore models. A first round of biological testing used hamster cells overexpressing human CYP11B1 or CYP11B2 to analyze 25 selected virtual hits. Three compounds inhibited CYP11B1 and CYP11B2 with IC50 values below 3 µM. The most potent inhibitor was epoxiconazole (IC50 value of 623 nM for CYP11B1 and 113 nM for CYP11B2, respectively); flurprimidol and ancymidol were moderate inhibitors. In a second round, these three compounds were tested in human adrenal H295R cells endogenously expressing CYP11B1 and CYP11B2, confirming the potent inhibition by epoxiconazole and the more moderate effects by flurprimidol and ancymidol. Thus, the in silico screening, prioritization of chemicals for initial biological tests and use of H295R cells to provide initial mechanistic information is a promising strategy to identify potential endocrine disruptors inhibiting corticosteroid synthesis. A critical assessment of human exposure levels and in vivo evaluation of potential corticosteroid disrupting effects by epoxiconazole is required.
Assuntos
Citocromo P-450 CYP11B2/antagonistas & inibidores , Bases de Dados de Produtos Farmacêuticos , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Compostos de Epóxi/farmacologia , Fungicidas Industriais/farmacologia , Esteroide 11-beta-Hidroxilase/antagonistas & inibidores , Triazóis/farmacologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/enzimologia , Neoplasias das Glândulas Suprarrenais/patologia , Sobrevivência Celular , Inibidores Enzimáticos/química , Compostos de Epóxi/química , Fungicidas Industriais/química , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Triazóis/química , Células Tumorais CultivadasRESUMO
Colorectal cancer (CRC) is one of the most frequent types of cancer in the world. Between tumor cells and the stroma mutual interconnections are established that favors the tumor development and metastasis. In this respect, the extracellular matrix is remodeled so that it may become totally different from a morphologic perspective than the stroma of the organ in which the tumor develops. Matrix metalloproteinases (MMPs) have an essential role in the remodeling of the tumor stroma. We assessed the expression of MMP-9 on a number of 31 stage III colorectal adenocarcinomas. Generally, MMP-9 had a high but inconstant expression in tumor cells. The highest expression was found in poorly and moderately differentiated carcinomas, with a lower expression in well-differentiated colorectal cancers. Occasionally, MMP-9 expression was identified also in peritumoral macrophages and in stromal cells. Metastasis-free lymph nodes had an intense positive reaction in both macrophages and lymphocytes. The intensely positive reaction was observed for the macrophages and lymphocytes in the tumor necrosis regions. The process of angiogenesis was generally correlated with the intensity of MMP-9 reaction.
Assuntos
Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/enzimologia , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Patológica/enzimologia , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Diferenciação Celular , Neoplasias Colorretais/patologia , Humanos , Linfonodos/enzimologia , Linfonodos/patologia , Macrófagos/enzimologia , Macrófagos/patologia , Células Estromais/enzimologia , Células Estromais/patologiaRESUMO
AIM: The present study investigated whether there is intratumoral heterogeneity of oncogenic driver mutations within surgically-resected tumors and between surgical specimens and percutaneous biopsy samples. PATIENTS AND METHODS: Thirty-four patients who underwent surgery for lung adenocarcinoma were studied. We obtained four to five snap-frozen samples from each surgical specimen. Mutational analyses of epidermal growth factor receptor (EGFR), Kirsten rat sarcoma viral homolog (KRAS), v-raf murine sarcoma viral oncogene homolog B (BRAF), and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit-alpha (PIK3CA) genes were performed and then compared in multiple surgical specimens and between surgical and percutaneous biopsy samples. RESULTS: EGFR and KRAS mutations were detected in 19 and 2 patients, respectively. Multiple surgical samples from different areas of the tumor had the same mutation genotype in all cases except for one. The 14 biopsy specimens had the same mutational profiles as the corresponding surgical specimens. CONCLUSION: Heterogeneous distributions of oncogenic driver mutations were not found in surgically-resected lung adenocarcinoma. Small tumor specimens obtained with percutaneous biopsy were suitable for EGFR analyses, thus providing critical information for personalized therapy.
Assuntos
Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Mutação , Adenocarcinoma/cirurgia , Adenocarcinoma de Pulmão , Adulto , Idoso , Biópsia , Classe I de Fosfatidilinositol 3-Quinases , Análise Mutacional de DNA , Receptores ErbB/genética , Feminino , Genes erbB-1 , Genes ras , Heterogeneidade Genética , Humanos , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras/genéticaRESUMO
Approximately 3-7% of non-small cell lung cancers harbor an anaplastic lymphoma kinase (ALK) gene fusion, constituting a new molecular subtype of lung cancer that responds to crizotinib, an ALK inhibitor. Although previous studies have evaluated ALK-rearranged lung cancers, the comprehensive analysis of lung cancer in Chinese has not well assessed. Herein, we identified 44 cases of ALK-rearranged samples by fluorescent in-situ hybridization (FISH), immunohistochemistry (IHC), and reverse transcription polymerase chain reaction (RT-PCR) in a large number of surgically resected lung cancers. All 44 ALK-rearranged lung cancers were adenocarcinomas, with 2 cases having additional focal squamous components. The goal was to analyse the clinicopathological features of ALK-rearranged lung adenocarcinomas. Our data showed that a cribriform structure, prominent extracellular mucus and any type of mucous cell pattern may be either sensitive or specific to predict an ALK rearrangement. We used FISH as the standard detection method. We compared the ALK rearrangement accuracy of FISH, RT-PCR and IHC. RT-PCR could define both the ALK fusion partner and the fusion variant, but seemed unable to detect all translocations involving the ALK gene. It is noteworthy that IHC using the D5F3 antibody (Cell Signaling Technology) showed higher sensitivity and specificity than the ALK1 antibody (Dako). Therefore, we conclude that IHC remains a cost-effective and efficient technique for diagnosing ALK rearrangements and that D5F3 can be the optimal screening antibody in clinical practice.
Assuntos
Povo Asiático/genética , Rearranjo Gênico/genética , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/enzimologia , Receptores Proteína Tirosina Quinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adenocarcinoma/diagnóstico , Adenocarcinoma/enzimologia , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Anticorpos Antineoplásicos/imunologia , China , Análise Mutacional de DNA , Feminino , Secções Congeladas , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/genética , Adulto JovemRESUMO
INTRODUCTION: In retrospective analyses of patients with nonsquamous non-small-cell lung cancer treated with pemetrexed, low thymidylate synthase (TS) expression is associated with better clinical outcomes. This phase II study explored this association prospectively at the protein and mRNA-expression level. METHODS: Treatment-naive patients with nonsquamous non-small-cell lung cancer (stage IIIB/IV) had four cycles of first-line chemotherapy with pemetrexed/cisplatin. Nonprogressing patients continued on pemetrexed maintenance until progression or maximum tolerability. TS expression (nucleus/cytoplasm/total) was assessed in diagnostic tissue samples by immunohistochemistry (IHC; H-scores), and quantitative reverse-transcriptase polymerase chain reaction. Cox regression was used to assess the association between H-scores and progression-free/overall survival (PFS/OS) distribution estimated by the Kaplan-Meier method. Maximal χ² analysis identified optimal cutpoints between low TS- and high TS-expression groups, yielding maximal associations with PFS/OS. RESULTS: The study enrolled 70 patients; of these 43 (61.4%) started maintenance treatment. In 60 patients with valid H-scores, median (m) PFS was 5.5 (95% confidence interval [CI], 3.9-6.9) months, mOS was 9.6 (95% CI, 7.3-15.7) months. Higher nuclear TS expression was significantly associated with shorter PFS and OS (primary analysis IHC, PFS: p < 0.0001; hazard ratio per 1-unit increase: 1.015; 95%CI, 1.008-1.021). At the optimal cutpoint of nuclear H-score (70), mPFS in the low TS- versus high TS-expression groups was 7.1 (5.7-8.3) versus 2.6 (1.3-4.1) months (p = 0.0015; hazard ratio = 0.28; 95%CI, 0.16-0.52; n = 40/20). Trends were similar for cytoplasm H-scores, quantitative reverse-transcriptase polymerase chain reaction and other clinical endpoints (OS, response, and disease control). CONCLUSIONS: The primary endpoint was met; low TS expression was associated with longer PFS. Further randomized studies are needed to explore nuclear TS IHC expression as a potential biomarker of clinical outcomes for pemetrexed treatment in larger patient cohorts.
Assuntos
Adenocarcinoma/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/mortalidade , Recidiva Local de Neoplasia/mortalidade , Timidilato Sintase/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Cisplatino/administração & dosagem , Feminino , Seguimentos , Glutamatos/administração & dosagem , Guanina/administração & dosagem , Guanina/análogos & derivados , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/enzimologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Pemetrexede , Prognóstico , Estudos Prospectivos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Timidilato Sintase/genéticaRESUMO
PURPOSE: Thymidylate synthase (TS) and thymidine phosphorylase (TP) expression have been shown to be predictors of response to therapy. The toxicity, efficacy, surgical morbidity, and immunohistochemical TS and TP expression were assessed in surgical resection specimens after preoperative chemoradiation. METHODS AND MATERIALS: Twenty patients with clinical stage I to III rectal adenocarcinoma received preoperative chemoradiation and underwent surgical resection 6 weeks later. RESULTS: Posttreatment tumor stages were T1 to T2 and N0 in 30% of patients; T3 to T4 and N0 in 30% of patients; and T1 to T3 and N1 to N2 in 15% of patients. Pathologic complete response (pCR) was evident in 25% and tumor regression occurred in a total of 80% of patients. Anal sphincter-sparing surgery was performed in 80% of cases. Acute and perioperative complications were minimal, with no grade 3/4 toxicity or treatment breaks. Pelvic control was obtained in 90% of patients. With a median follow-up of 65.5 months (range, 8-80 months), the 6-year actuarial survival rate was 75%. Local failure was significantly associated with nonresponse to therapy and with high TS and low TP expression (p = 0.008 and p = 0.04, respectively). CONCLUSIONS: The combination of capecitabine, celecoxib, and x-radiation therapy yields excellent response: a 25% pathologic pCR, no acute grade 3/4 toxicity, and minimal surgical morbidity. Nonresponders expressed significantly increased TS levels and decreased TP levels in posttreatment resection specimens compared to responders.
Assuntos
Adenocarcinoma , Biomarcadores Tumorais/metabolismo , Neoplasias Retais , Timidina Fosforilase/metabolismo , Timidilato Sintase/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina , Celecoxib , Terapia Combinada/métodos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Pirazóis/administração & dosagem , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/enzimologia , Neoplasias Retais/patologia , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Sulfonamidas/administração & dosagem , Taxa de Sobrevida , Adulto JovemRESUMO
AIM: The mechanism by which neoplasias respond to hypoxia determines their biological behavior and prognosis. Understanding the biology of tumors under hypoxic conditions is crucial for the development of anti-angiogenic therapy. Using the largest cohort of rectal adenocarcinomas to date, this study aimed to assess microvessel density (MVD) and carbonic anhydrase-9 (CA-9) expression and to correlate the results with recurrence and cancer-specific survival. MATERIALS AND METHODS: Patients (n=101) who underwent surgery for rectal adenocarcinoma without previous neoadjuvant therapy or metastatic disease were selected. MVD and CA-9 expression were assessed immunohistologically by using the CD34 antibody and the MN/CA9 M75 antibody, respectively. In a multifactorial analysis, the results were correlated with tumor stage, recurrence rate, and long-term survival. RESULTS: MVD was higher with increased T- and N-stages (p<0.01) and associated positively with poor survival (hazard ratio (HR) 1.3 per 10 vessel increase, p<0.01). CA-9 was expressed in 73% of cancers. Negative lymph node status correlated with CA-9 positivity (p<0.05), reflected in a higher rate of CA-9 positivity in earlier Dukes' stages (p<0.05). CA-9 positivity across tumor node metastasis (TNM) stages approached significance (Stage I/II: 80% CA-9 positive vs. 20% CA-9 negative; Stage III: 63% CA-9 positive vs. 37% negative, p=0.051). A trend was seen towards better cancer-specific survival in patients with CA-9 positive carcinomas (HR 0.51, p=0.07) on univariate analysis. DISCUSSION: MVD was higher in more advanced T- and N-stages and may be used as a determinant of survival in patients with rectal adenocarcinomas. CA-9 expression was seen more often in earlier Dukes' stages, possibly representing an early tumor hypoxic response. CA-9 expression by adenocarcinoma cells may confer long-term survival advantage in surgically treated rectal cancer.
Assuntos
Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/enzimologia , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Anidrases Carbônicas/análise , Microvasos/patologia , Neoplasias Retais/irrigação sanguínea , Neoplasias Retais/enzimologia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Anidrase Carbônica IX , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Recidiva , Medição de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Prostate cancer is the most common malignancy affecting men and is a major cause of cancer death. There are increasing data on novel tumor markers, such as gelatinase A, which play a key role in tissue invasion and metastasis. OBJECTIVES: We designed a study to evaluate total gelatinase A content using a simple and applicable Indirect hemagglutination (IHA) test in harmony with gelatinase A activity in serum samples as compared with prostate-specifc antigen (PSA) parameters. METHODS: In this study, we analysed the circulating form of gelatinase A (MMP-2) in patients suffering from either benign prostate hyperplasia (n=54) or prostate cancer (n=26) versus normal individuals as control (n=26). The gelatinolytic activity was determined by zymography and total MMP-2 content was measured by a novel IHA method. Total PSA and free PSA were quantified using a standard ELISA technique. RESULTS: Correlation of densitometric analysis of gelatinase A activity and IHA titer is significant at the 0.01 level (P<0.01, rho=0.916). Correlation of PSA and IHA titer is significant at the 0.01 level (P<0.01, rho=0.746). Correlation of free PSA and IHA titer is significant at the 0.01 level (P<0.01, rho=0.749). Borderline of IHA titer in patients with prostate cancer was 512+/-1 tube titer, in benign prostate hyperplasia patients was 128+/-1 tube titer and the titer in normal individuals was 8+/-1 tube titer. CONCLUSIONS: These results demonstrate that assessment of gelatinase A might be a promising procedure for monitoring and screening patients with prostate cancer.
Assuntos
Adenocarcinoma/sangue , Adenocarcinoma/enzimologia , Metaloproteinase 2 da Matriz/sangue , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/enzimologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Testes de Hemaglutinação , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Prostáticas/sangue , Doenças Prostáticas/enzimologiaRESUMO
In a series of pairs of lung tumor tissue and non-tumor lung parenchyma from 50 patients, the activity of cathepsin L was measured with Z-Phe-Arg-AMC using the inhibitor CA-074 to delimitate from cathepsin B activity also present in the tissue extracts. Cathepsin B was assessed in the same samples with its specific substrate Z-Arg-Arg-AMC. It was found that in tumor tissue the median activities of cathepsin L and cathepsin B were increased 1.6-fold and 4.9-fold, respectively. The levels of activity of both enzymes did not correlate with TNM stages nor with cell differentiation of bronchial carcinomas. Cathepsin L activity was found to be insignificantly higher in adenocarcinoma compared to squamous cell carcinoma, while cathepsin B activity did not vary across the histologies. The activities of both enzymes were low in pulmonary carcinoids, which are known to be low-grade malignant neoplasms. The amount of cathepsin B activity exceeded by far that of cathepsin L activity as proven by measurement with Z-Phe-Arg-AMC in the presence of the inhibitor Z-Phe-Phe-CHN2:95-98% of cathepsin B activity vs 2-5% of cathepsin L activity were determined. By SDS-PAGE separation and immunoblot analysis, it could be demonstrated that significant amount of cathepsin L is complexed with the cysteine proteinase inhibitor kininogen. This explains the rather low cathepsin L activity values in the tissue extracts.
Assuntos
Catepsina B/análise , Catepsinas/análise , Cisteína Endopeptidases/análise , Dipeptídeos , Endopeptidases , Neoplasias Pulmonares/enzimologia , Adenocarcinoma/enzimologia , Adulto , Idoso , Sequência de Aminoácidos , Western Blotting , Carcinoma de Células Escamosas/enzimologia , Catepsina B/antagonistas & inibidores , Catepsina B/metabolismo , Catepsina L , Catepsinas/antagonistas & inibidores , Catepsinas/isolamento & purificação , Cisteína Endopeptidases/isolamento & purificação , Inibidores de Cisteína Proteinase/análise , Inibidores de Cisteína Proteinase/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Humanos , Cininogênios/metabolismo , Pulmão/enzimologia , Pessoa de Meia-Idade , Dados de Sequência MolecularRESUMO
Sensitivity of 142 human large bowel malignancies to gastroenteropancreatic hormones (VIP, glucagon and pentogastrin) and calcitonin was studied using in vitro adenylate cyclase reaction of tumor. At least 40-55% of the tumors proved hormone sensitive. Heteroresponse (reaction to calcitonin) was most characteristic for colonic tumors whereas weak reaction to VIP and glucagon-for rectal neoplasms. A certain relationship was established between adenylate cyclase reaction to hormone stimulation, on the one hand, and peculiarities of tumor (degree of cell differentiation) and the body (gender), on the other. In patients who survived over 4 years, tumor adenylate cyclase had initially been more sensitive to hormone stimulation than in those who died over that period. It is concluded that tumor adenylate cyclase reaction to hormone stimulation is quite a reliable test for evaluating hormone sensitivity of large bowel tumors and, possibly, for choosing hormonal therapy.
Assuntos
Adenocarcinoma/tratamento farmacológico , Adenilil Ciclases/efeitos dos fármacos , Carcinoma/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Hormônios Gastrointestinais/uso terapêutico , Neoplasias Primárias Múltiplas/tratamento farmacológico , Neoplasias Retais/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/mortalidade , Adulto , Idoso , Carcinoma/enzimologia , Carcinoma/mortalidade , Neoplasias do Colo/enzimologia , Neoplasias do Colo/mortalidade , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/enzimologia , Intestino Grosso/efeitos dos fármacos , Intestino Grosso/enzimologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/enzimologia , Neoplasias Primárias Múltiplas/mortalidade , Neoplasias Retais/enzimologia , Neoplasias Retais/mortalidade , Caracteres SexuaisRESUMO
A two site enzyme immunoassay which quantitatively identifies types I, II, and III of protein kinase C isozymes has been designed. The soluble protein kinase C isozymes were selectively immobilized by type-specific monoclonal antibodies, MC-1a, -2a, and -3a (H. Hidaka et al., J Biol. Chem., 263: 4523-4526, 1988) which bind to the regulatory domain (NH2-terminal side) of protein kinase C. The amount of each isozyme was then determined using a horseradish peroxidase-conjugated polyclonal antibody raised against the COOH-terminal peptide of protein kinase C. By adding increasing concentrations of the antigen, the range of the assay proved to be 0.51-51, 0.081-8.1, and 0.31-31 nM for types I, II, and III, respectively. This sandwich method was used to determine the level of protein kinase C isozymes in rabbit tissues. Type I was mainly present in the cerebrum and cerebellum; the highest amount of type II isozyme was present in blood platelets [26.0 +/- 3.8 (SE) micrograms/g wet tissue]. We compared the protein kinase C isozyme levels in human normal thyroid gland and thyroid cancer tissues and found that type II protein kinase C specifically increased in thyroid cancer tissues. Immunocytochemical examination using MC-2a revealed that the cytoplasm of the cancer cells showed prominent immunoreactivity for type II isozyme.
Assuntos
Adenocarcinoma/enzimologia , Isoenzimas/análise , Proteína Quinase C/análise , Neoplasias da Glândula Tireoide/enzimologia , Adenocarcinoma/patologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais , Encéfalo/enzimologia , Membrana Celular/enzimologia , Reações Cruzadas , Citosol/enzimologia , Epitopos/análise , Humanos , Técnicas Imunoenzimáticas , Isoenzimas/biossíntese , Dados de Sequência Molecular , Peso Molecular , Especificidade de Órgãos , Peptídeos/síntese química , Proteína Quinase C/biossíntese , Coelhos , Neoplasias da Glândula Tireoide/patologiaRESUMO
We have investigated the role of ornithine decarboxylase activity in rectal mucosa as a marker for colorectal neoplasia. Biopsies of normal rectal mucosa were taken from 18 patients with adenomas greater than 1 cm diameter, 11 with carcinomas and 16 controls. The mean ornithine decarboxylase activity in normal rectal mucosa of adenoma patients, 6.52 nmol CO2 released h-1 (mg cell protein)-1, was significantly lower than that in controls, 16.8, P = 0.006. The difference in rectal ornithine decarboxylase activities between cancer patients, 3.58, and controls was also significant, P = 0.001. These preliminary results suggest that ornithine decarboxylase may be a useful marker in screening for colorectal neoplasia.