Expressão citofotométrica dos marcadores tumorais CD-34 e fator VIII no câncer de cólon / Cytophotometric expression of the tumor markers CD-34 and factor VIII in colorectal cancer

OBJETIVOS: Verificar a posssibilidade de quantificar a expressão dos marcadores tumorais CD-34 e Fator VIII no câncer de cólon; verificar se existe superioridade entre um marcador e outro para estudo da angiogênese; verificar se há correlação na análise do índice de marcagem e a densidade óptica média nos marcadores utilizados. MÉTODOS: Dezessete casos de adenocarcinoma colorretal recuperados de blocos de parafina e confirmados pela hematoxilina-eosina, foram submetidos à coloração imunoistoquímica pelo método da estreptoavidina-biotina-peroxidase e utilizados os marcadores tumorais CD-34 e Fator VIII. Após este processo as lâminas foram submetidas à leitura no sistema Samba 4000® e avaliadas pelo software Immuno®. Os parâmetros estudados foram: índice de marcagem e densidade óptica, expressos por médias, medianas, valores mínimos, valores máximos e desvios-padrão, analisados estatisticamente. RESULTADOS: Para o marcador CD-34 não houve normalidade dos dados em relação ao índice de marcagem e houve para a densidade óptica. Para o Fator VIII, houve normalidade de dados em relação ao índice de marcagem e para a densidade óptica. CONCLUSÃO: Foi possível quantificar a expressão dos marcadores tumorais CD-34 e Fator VIII através do índice de marcagem e da densidade óptica média; não houve diferença entre os marcadores em relação à média do índice de marcagem e da densidade óptica, não sendo possível definir superioridade entre um e outro; não foi observada tendência à correlação quando comparados densidade óptica e índice de marcagem do Fator VIII e do CD-34 isoladamente estudados; não houve correlação entre o índice de marcagem do Fator VIII quando comparado com o CD-34, bem como a densidade óptica do Fator VIII com o CD-34.

OBJECTIVES: In colorectal cancer, to describe the cytophotometric expression of the CD-34 and Factor VIII; to evaluate the degree of correlation between them; and to compare the CD-34 and Factor VIII expressions in relationship to label index and optical density. METHODS: Seventeen cases of colorectal adenocarcinoma recovered from paraffin-embedded archival tissue and confirmed by hematoxilin-eosin staining, were submitted to streptavidin-biotin-peroxidase immunohistochemical method. In this process was used the tumor markers CD-34 and Factor VIII. The obtained slides were analysed using the SAMBA 4000® system with Immuno® software. The results were evaluated into two parameters: label index and optical density, and expressed by averages, medians, minimum values, maximum values, and standard deviation values. The normality condition of the quantitative variables was investigated by using the Shapiro-Wilks test. In order to evaluate the degree of association between the expressions of the markers, Pearson's Correlation Coefficient or Spearman's Correlation Coefficient were applied. To evaluate the comparison degree of the markers expression, Student's t test or Wilcoxon's no parametric test were used. RESULTS: For the CD-34 there was no data normality for the label index and there was normality in the optical density. For the Factor VIII, there was data normality for the label index and for the optical density. CONCLUSION: When the expressions of CD-34 and Factor VIII markers were correlated, there was no difference between them in relationship to the average label index and average optical density. When the expressions of the CD-34 and Factor VIII were compared, there was no correlation between the two variables.

Influence of antiangiogenic fraction from Diogenes avarus (Heller) on fertility and implantation in mice.

The methanol extract isolated from hermit crab, D. avarus degenerated ovarion and uterine tissues in cyclic and pregnant mice, treated before and after the implantation. Immunohistochemical staining using CD31 and Factor VIII specific to endothelial cells showed reduction in microvessel density. The hormonal assay showed decrease in the progesterone secretion in all experimental mice.

Expression and characterization of a mutant recombinant blood coagulation factor VIII (rFVIII (m))

In an earlier study, a site directed mutant rFVIII (rFVIII(m), Arg(336) -> Gln(336)) expressed in baculovirus-insect cell (Sf9) system was found to sustain high level activity during incubation at 37 for 24 h while the cofactor activity of normal plasma was declined steadily. In this study, a mutant B-domain deleted rFVIII(m), Arg(336) -> Gln(336) expressed in baculovirus-insect cell (Sf9) system was characterized for its enzymatic and chemical properties. The expressed rFVIII(m) and plasma FVIII (pFVIII) were purified by immunoaffinity column chromatography and identified by Western blot analysis. The partially purified rFVIII(m) exhibited cofactor specific activity of 2.01 X 10(3)units/mg protein. The molecular weight of rFVIII(m) ranged between 40 to 150 kDa with a major band at 150 kDa. Treatment of both rFVIII(m) and pFVIII with thrombin increased their cofactor activity in a similar pattern. Treatment of both the activated rFVIII(m) and native FVIII with APC decreased their cofactor activities, however, the former exhibited a slower decrease than the latter, although no significant difference was present. rFVIII(m) formed a complex with vWF, resulting in a stabilized form, and the lag period of thrombin-mediated activating was extended by vWF association. These results implicated that rFVIII(m) expressed in baculovirus-insect cell system had a comparable capacity as FVIII cofactor activity and might be a good candidate for the FVIII replacement therapy for hemophilia A patients.

Synthesis of recombinant blood coagulation factor VIII (FVIII) heavy and light chains and reconstitution of active form of FVIII

FVIII is synthesized as a single chain precursor of approximately 280 kD with the domain structure of A1-A2-B-A3-C1-C2 and it circulates as a series of metal ion-linked heterodimers that result from cleavages at B-A3 junction as well as additional cleavages within B domain. Factor VIII is converted to its active form, factor VIIIa, upon proteolytic cleavages by thrombin and is a heterotrimer composed of the A1, A2, and A3-C1-C2 subunits. A1 subunits of factor VIIIa terminates with 36 residue segment (Met337-Arg372) rich in acidic residues. This segment is removed after cleavages at Arg336 by activated protein C, which results in inactivation of the cofactor. In the present study, site-directed mutagenesis of FVIII at Arg336 to Gln336 was performed in order to produce an inactivation resistant mutant rFVIII (rFVIIIm) with an extended physiological stability. A recombinant mutant heavy chain of FVIII (rFVIII-Hm; Arg336 to Gln336) and wild-type light chain of FVIII (rFVIII-L) were expressed in Baculovirus-insect cell (Sf9) system, and a biologically active recombinant mutant FVIII (rFVIIIm) was reconstituted from rFVIII-Hm and rFVIII-L in the FVIII-depleted human plasma containing 40 mM CaCl2. The rFVIIIm exhibited cofactor activity of FVIIIa (2.85 x 10(-2) units/mg protein) that sustained the high level activity during in vitro incubation at 37 degrees C for 24 h, while the cofactor activity of normal plasma was declined steadily for the period. These results indicate that rFVIIIm (Arg336 to Gln336) expressed in Baculovirus-insect cell system is inactivation resistant in the plasma coagulation milieu and may be useful for the treatment of hemophilia A.

A pathologic study of abdominal lymphangiomas

Abdominal lymphangiomas are uncommon angiomatous tumor occurring mainly in childhood. This is a retrospective clinicopathologic study of 17 cases of abdominal lymphangioma. The patients included are five children and 12 adults, with a mean age at initial presentation of 30.7 years (age ranges 3-63). The locations of the tumors were mesentery (5), retroperitoneum (4), colon (3), omentum (3), mesocolon (1) and gallbladder (1). Infiltrative growth was more common pattern than entirely circumscribed pattern. Masses were mostly multilocular cysts and contained chyle or serous fluid. On immunohistochemical staining, 16 cases were reactive for either CD31 or factor VIII-related antigen. These fact would suggest that intra-abdominal lymphangiomas simulate the immunohistochemical features of collecting lymphatics. Follow up was possible in 12 cases for 3-50 months (mean 19 months) and only one patient showed local recurrence. Although abdominal lymphangiomas are rare in adulthood and correct preoperative diagnosis is difficult, awareness of such a possibility in adulthood will contribute to make a correct preoperative diagnosis.