Keiko Komatsu

Multiple forms of human adenosine deaminase: I. Purification and characterization of two molecular species

Abstract 1. 1. Gel filtration of human tissue extracts with Sephadex G-200 revealed the existence of two molecular species of adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4) differing markedly in their molecular sizes. 2. 2. Tissue-specific distributions of these species were also revealed. 3. 3. The larger and smaller enzymes were purified more than 1000-fold, nearly to homogeneity, from the lung and the stomach, respectively. 4. 4. Determination of molecular weights of the enzymes using a calibrated Sephadex G-200 column resulted in the values of 230 000 and 47 000, which were in reasonable accordance with the values obtained by sucrose density gradient centrifugation. 5. 5. No significant differences were observed enzymically or immunologically between the properties of the two enzymes except for their heat-stabilities and molecular activities. 6. 6. A reversible conversion of the larger deaminase to the smaller was demonstrated when the former was treated with guanidine. 7. 7. The smaller enzyme was apparently converted to the larger after incubating the former enzyme sample with crude lung supernatant. 8. 8. The possible structural relationship between the two species of human adenosine deaminase is discussed.

Expression of S100A6 and S100A4 in Matched Samples of Human Colorectal Mucosa, Primary Colorectal Adenocarcinomas and Liver Metastases

Objective: S100A6 and S100A4, two of S100 protein family, have been suggested to be associated with cancer tumorigenesis and metastasis. The aim of this study was to evaluate the expression levels of S100A6 and S100A4 in matched samples of primary human colorectal adenocarcinomas (T), adjacent normal colorectal mucosa (N) and liver metastases (M). This gave us the advantage of directly comparing levels of S100A6 and S100A4 expression within the same genetic background. Methods: In matched samples of N, T and M from 10 colorectal adenocarcinoma patients, expressions of S100A6 and S100A4 were studied by Western blot and immunohistochemical analyses using specific antibodies against each protein. Results: The expression levels of S100A6 were significantly higher in T than in N (p < 0.05), while those of S100A4 showed no difference between T and N. There were no significant differences in the expression levels of S100A6 or S100A4 between M and T. Similar results were obtained by immunohistochemical analysis. Moreover, S100A6 was stained more intensely in invading fronts than in central portions of both T and M. Conclusions: The observed differential expression of S100A6 and S100A4 suggests that S100A6, rather than S100A4, is associated with human colorectal adenocarcinoma tumorigenesis and invasion/metastasis.

Enhancement of mucus accumulation in a human gastric scirrhous carcinoma cell line (KATO-III) by fibroblast-tumor cell interaction.

SummaryHuman fibroblasts (WI-38 cells) were found to enhance mucus accumulation by human scirrhous carcinoma cells (KATO-III cells). Coculture of KATO-III with WI-38 cells resulted in enlargement of the KATO-III cells and increases in the proportions of PASand colloidal ironpositive KATO-III cells. These morphological alterations were reversed when the KATO-III cells were again cultured without WI-38 cells. Conditioned media from cultures of WI-38 cells or cocultures of KATO-III and WI-38 cells induced the same morphological alterations in KATO-III cells, suggesting that WI-38 cells produce a factor or factors that enhance mucus accumulation in KATO-III cells. This factor seemed to be a protein with a molecular weight of more than 10000 daltons.

Induction of autologous graft-versus-host disease after autologous peripheral blood stem cell transplantation

BACKGROUND Autologous graft-versus-host disease has been reported after the administration of cyclosporine in patients who have received autologous bone marrow transplantation. OBJECTIVE The purpose of this study was to determine whether autologous graft-versus-host disease could be induced in recipients of autologous peripheral blood stem cell transplantation and whether tacrolimus induced the disease instead of cyclosporine. METHODS Twelve patients with acute leukemia and 5 patients with malignant lymphoma received either cyclosporine (1 mg/kg/day) or tacrolimus (0. 05 mg/kg/day) orally after autologous bone marrow or peripheral blood stem cell transplantation. RESULTS Autologous graft-versus-host disease of the skin, confirmed by histopathologic criteria, occurred in 40% of the patients at 8 to 25 days after transplantation and lasted 3 to 15 days. The frequency of autologous graft-versus-host disease was approximately the same (40%) irrespective of the source of the graft (bone marrow cells or peripheral blood stem cells) and the drug used for induction (cyclosporine or tacrolimus). CONCLUSIONS This pilot study suggests that autologous graft-versus-host disease can be induced in recipients of autologous peripheral blood stem cell transplantation by cyclosporine or tacrolimus.

Human leukemic cells contain transforming growth factor

A transforming growth factor was found in the extracts of leukemic cells obtained from the peripheral blood of 11 patients with leukemia. This factor stimulated the colony formation of anchorage-dependent BALB/c 3T3 cells in soft agar. The high levels of colony-stimulating activities were observed in the cell extracts from patients with chronic myelogenous leukemia in blastic crisis (CML BC), acute myelogenous leukemia and CML in chronic phase. The factor from a CML BC patient was heat- and acid-labile, relatively stable to dithiothreitol treatment and inactivated by pronase treatment. Molecular size of the factor seems more than 10,000 daltons.