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One human body is composed of 6 x 10(13) cells, and eyes are also composed of many cells of different functions. The cellular functions and intercellular interaction are regulated by many regulators including cytokines and growth factors to maintain the homeostasis. The transforming growth factor-beta (TGF-beta) superfamily, a large family of multifunctional factors, regulates various cellular functions, including cellular proliferation, migration, differentiation, apoptosis and extracellular matrix production. The TGF-beta superfamily contains about 30 multifunctional factors, and is divided into several families according to the sequence homology. The TGF-beta family, the activin family, and bone morphogenic proteins belong to the TGF-beta superfamily. TGF-beta superfamily members transduce signals through type I and type II serine/threonine type transmembrane receptors. The signals are transduced from receptors through nuclei by Smad family members, which are phosphorylated by the activated type I receptors and translocate from cytoplasm into nuclei. TGF-beta family members and the TGF-beta superfamily receptor family are expressed in ocular tissues including the cornea, ciliary epithelium, lens epithelium, retina, and blood vessels. This observation suggests the importance of the TGF-beta superfamily in eyes. Smad family members (Smad 1, Smad 2, Smad 3 and Smad 4) are expressed in the cultured retinal pigmant epithelial cell line (D407), in which TGF-beta and activin A stimulate the translocation of Smad 2, but not Smad 1 into nuclei, whereas bone morphogenetic protein (BMP) stimulates that of Smad 1, but not Smad 2. TGF-beta superfamily members play important roles in the pathogenesis of retinal neovascularization and in the wound healing process of corneal tissue. TGF-beta inhibits the endothelial functions, but, stimulates angiogenesis in vivo. TGF-beta is involved in the formation of abnormal connective tissue in corneal wound healing. In these processes, many cytokines and growth factors are involved, interacting with each other and forming networks. It is mandatory to clarify the networks to investigate molecular pathogenesis and new therapeutic agents.

A 84-year-old man was admitted with diabetes mellitus, hypertension and chronic renal failure in September 1994. In October 1995, his renal function gradually worsened with hyperkalemia. Sodium polystyrene sulfonate (Kayexalate) was administered orally for the treatment of hyperkalemia. However, after 7 days from the start of Kayexalate therapy, thrombocytopenia progressed gradually, and 12 days later the initial platelet count of 20.7 x 10(4)/microliter decreased to 8.6 x 10(4)/microliter. This thrombocytopenia rapidly improved after cessation of Kayexalate administration. In December 1995, readministration of Kayexalate for the treatment of hyperkalemia induced thrombocytopenia again. Bone marrow aspiration biopsy revealed normal counts of nucleated cells and megakaryocytes with no increase in blasts. No other disorders which cause thrombocytopenia were seen in this patient. The complication of thrombocytopenia associated with Kayexalate has not been reported. This is the first reported case of thrombocytopenia caused by Kayexalate administration.

A 69-year-old woman was admitted with apoplexy after operation of mitral valve stenosis and gastrectomy due to a gastric ulcer. In June 1994, her condition gradually worsened after acute pneumoniae in her right lung. Intravenous hyperalimentation with cimetidine administration was started to improve her undernourishment, because she had a history of gastric ulcer. However, after 10 days from the start of cimetidine therapy, anemia progressed rapidly. Biochemical examinations revealed that the serum indirect bilirubin and LDH levels were elevated and no serum haptoglobin was detected. These results indicated the development of hemolytic anemia, but at that time we could not clarify the reason. In October 1994, thrombocytopenia gradually progressed, and we halted the administration of cimetidine to ranitidine. Both hemolytic anemia and thrombocytopenia was dramatically improved after cessation of cimetidine administration. We then changed the drug from cimetidine, however the same phenomena have appeared again. The patient was in stable condition, after cessation of H2-blockers administration. The complication of hemolytic anemia and thrombocytopenia associated with H2-blocker administration in Japan.

In the present paper, we investigated the pathophysiological implication of TGF-beta from megakaryocytes or megakaryoblasts in the development of myelofibrosis. In the bone marrow of myelofibrosis, proliferation of megakaryocytes is often noticed. We therefore investigated the TGF-beta expression in the bone marrow megakaryocytes from 12 chronic myeloproliferative disorder patients with myelofibrosis by immunohistochemical analysis. About all the specimen showed strong positivity for TGF-beta. In order to examine whether megakaryoblasts produce TGF-beta, we then measured TGF-beta activity in the conditioned medium (CM) of megakaryoblasts from a patient with acute megakaryoblastic leukemia who had profound myelofibrosis. The CM showed strong collagen synthesis stimulating activity which was nullified by addition of anti TGF-beta antibody. Since TGF-beta exists as latent form in platelets, TGF-beta was considered to be altered from active to latent form during megakaryocytes differentiation. In this context, MEG-01, a megakaryoblastic cell line which produces active TGF-beta was underwent differentiation to produce platelet-like bleb with TPA treatment. During the differentiation, MEG-01 showed the decrease of active TGF-beta production and increase of latent TGF-beta together with the production of LTBP. These results suggest that megakaryoblasts produce active TGF-beta and may may cause myelofibrosis, while more differentiated megakaryocytes produce latent TGF-beta. Mechanism by which megakaryoblast escape from negative autocrine of active TGF-beta was also investigated. MEG-01 was found to express mutated p53 which is considered to be responsible for impaired signal transduction of TGF-beta.

A 62 year old male patient was previously admitted to another hospital in February 1989 because of palpitation. Peripheral blood examination revealed pancytopenia. Although the number of nucleated cells in the bone marrow aspirate was in the normal range. It contained 2.2% of blastic cells and dysplastic cells. He was diagnosed to be myelodysplastic syndrome with refractory anemia. He subsequently received repeated blood transfusions and other symptomatic treatments as an outpatient until 1990. When he was admitted to our hospital because of severe pancytopenia. The numbers of WBC, RBC, and platelets were 2,000/microliters, 134 x 10(4)/microliters, 2.9 x 10(4)/microliters respectively. Bone marrow aspiration resulted in dry tap, and biopsy at the iliac bone showed remarkable fibrosis with marked decrease of normal hematopoietic cells. Chromosome analysis revealed multiple aberrations such as 47XY, +8, 13q-, 14p+, 48XY, +8, +9, 13q+. The patient was treated with BHAC-AMP combination chemotherapy. After 3 cycles of the therapy, pancytopenia was improved and chromosomal aberration disappeared. This case was considered to be an acute myelofibrosis developed from myelodysplastic syndrome and worth to reporting with a review of literature, because drastic combination chemotherapy was extremely effective.

Specific DNA probes for genes encoding immunoglobulins (Ig) and the T cell receptor (TCR) are useful diagnostic tools in lymphoproliferative disorders. Gene rearrangement analysis was carried out in 2 cases of conjunctival lymphoid lesions. A 36-year-old man (case 1) had a 1-year history of left conjunctival tumor. A biopsy was performed and histopathological findings showed diffuse proliferation of small lymphocytes, but monoclonality was not revealed by immunophenotypic analysis. A right conjunctival lesion developed and five months later a biopsy of the left conjunctiva was performed again. A frozen sample was analyzed and immunoglobulin heavy chain gene rearrangement was found. A 53-year-old woman (case 2) had a 6-month history of bilateral conjunctival tumor. The first biopsy did not reveal monoclonality immunophenotypically. A second biopsy with a frozen specimen was analyzed and immunoglobulin heavy chain gene rearrangement was found. We diagnosed these two cases as B-cell lymphoma. We discuss the clinical value of gene rearrangement analysis as a diagnostic method for lymphoproliferative disorders.

A 63-year-old male with refractory anemia with excess of blasts (RAEB) and hypoplastic marrow was treated with K-18 (240 mg/day P.O.). On admission, peripheral blood revealed pancytopenia. Bone marrow specimen revealed severe hypocellularity with 18.9% of the blast cells. Ten months later, the blast cells in the bone marrow decreased to 3.8%, and complete remission (CR) was obtained. CR was eight weeks. Duration of response (CR + PR) continued for about eight months. K-18 is an antitumor agent with minimal side effects, and seems to be effective for RAEB with hypoplastic marrow.

Attempts were made to clarify the mechanism of platelet aggregation and to characterize the platelet aggregating material employing established human cancer cell lines. Eleven out of the nineteen human cancer cell lines investigated showed platelet aggregating activity. The existence of divalent cation was required for the platelet aggregation induced by HMV-1 tumor cells. The platelet aggregations induced by tumor cells (HMV-1, PC-10, 3LL) were not suppressed by specific thrombin inhibitor (MD-805). The platelet aggregating activities of tumor cells (HMV-1, M 7609) were diminished by treatment with trypsin but not with collagenase or neuraminidase. Aggregating activity was preserved with a preparation of membrane from these tumor cells, although it was abolished by heating(100 degrees C 15 min) or sonication. By SDS PAGE (autoradiography), membrane proteins with MW of 20,000 daltons which specifically bound to platelets were commonly found in cells with platelet aggregating activity (HMV-1, M 7609), but were absent in platelet non-aggregating cells (HGC-25). It is therefore concluded that platelet aggregation induced by human tumor cells does not require the coexistence of thrombin, but is evoked by direct interaction of platelets with aggregating proteins (MW 20,000 daltons) on the cell membrane.

A 63-aged woman with cutaneous T cell lymphoma successfully treated with local administration of tumor necrosis factor (TNF) was reported. She was admitted to our hospital because of tumors and subcutaneous nodules on her bilateral inner thigh. A pathological study of her skin of right inner thigh showed mononuclear atypical cells with hyperlobulated nuclei. In peripheral blood the same lymphoid cells were found. Immunohistochemical staining of these cells was positive for OKT-3 and OKT-4, but negative for OKT-8. No lymph node swelling and no visceral involvement were detected by a CT scan and a Echography of the chest and the abdomen. A diagnosis of cutaneous T cell lymphoma was made (stage IIb TNM classification). Although the chemotherapy of VEPA and CHOP was done, about 70% (PR) of the bilateral inner thigh tumors were retracted. Owing to the interstitial pneumonia aroused in the period of bone marrow suppression and cardiomyopathy after chemotherapy, we gave up further systemic chemotherapy. And then the local administration of TNF was done and the disappearance of the bilateral inner thigh tumors was obtained. Our therapy with local administration of TNF for CTCL in the first report.

To elucidate the correlation of platelet aggregating activity of tumor cells and their metastatic potentials, we established a highly and a low metastatic clone with a different platelet aggregating activity from murine fibrosarcoma (Meth A). The parental Meth A cell and its low metastatic clone (ML-01) showed a typical platelet aggregation pattern with a certain lag time, while a highly metastatic clone (MH-02) showed a biphasic aggregation with no lag time in which the first reversible aggregation was caused by ADP released from MH-02, since it was eliminated by apyrase treatment. The highly metastatic potential, however, was not solely due to the platelet aggregating activity because the administration of PGI2-analogue TEI-8153A did not completely inhibit their pulmonary metastasis. In fact, MH-02 attached more preferentially to type IV collagen or endothelial cell than ML-01 in vitro. These results suggest that MH-02 exerts its high metastatic property through the mechanisms involving multiple factors such as the increased platelet aggregating potential or enhanced adhesiveness.