Mikio Tanino

Isolation of a highly metastatic cell line to lymph node in human oral squamous cell carcinoma by orthotopic implantation in nude mice

To isolate a variant cell line with increased lymph node metastasising potential from human oral squamous cell carcinoma (SCC) we performed in vivo selection using orthotopic implantation in nude mice. Human oral SCC cells (HSC-3) were injected orthotopically into the tongue of nude mice. After 3 weeks their cervical lymph nodes were excised and the tumour cells metastasised to the lymph nodes were isolated and injected into the tongue of nude mice again, this procedure was performed three times. The resultant cells, designated as HSC-3-M3, metastasised to cervical lymph nodes in 90% of mice, while parental HSC-3 cells metastasised in only 30% of mice after injection into the tongue. HSC-3 and HSC-3-M3 cell lines which have the same origin but different lymphatic metastatic capacities could be a useful model system for studying mechanisms involved in lymph node metastasis of human oral SCC.

A bitter diterpenoid furanolactone columbin from Calumbae Radix inhibits azoxymethane-induced rat colon carcinogenesis

The modifying effect of dietary administration of a diterpenoid furanolactone columbin isolated from the crude drug Calumbae Radix (the root of Jateorhiza columba MIERS, Menispermacea) on azoxymethane (AOM)-induced was investigated in male F344 rats. Animals were initiated with AOM (three weekly subcutaneous injections of 15 mg/kg body weight) to induce colonic neoplasms. They were fed the experimental diets mixed with columbin (4, 20, and 100 ppm) for 4 weeks, starting 1 week before the first dosing of AOM and thereafter maintained on the basal diet without columbin. Additional experimental groups included the AOM alone group, the columbin alone group (100 ppm in diet for 4 weeks), and the untreated control group. Dietary feeding of columbin (4, 20, and 100 ppm) during the initiation phase of AOM-induced colon carcinogenesis reduced the incidence and multiplicity of colonic adenocarcinoma and the inhibition by feeding of 20 ppm (incidence: 20%, P=0.0242 and multiplicity: 0.20+/-0.40, P<0.02) and 100 ppm (incidence: 10%, P=0.0029 and multiplicity: 0.10+/-0.30, P<0.002) columbin was significant when compared with the AOM alone group (incidence: 55% and multiplicity: 0.55+/-0.50). Also, columbin administration in diet lowered the number of argyrophilic nucleolar organizer regions protein per nucleus in non-lesional colonic crypts and the blood polyamine content, which are reflected in cell proliferation activity. These results indicate chemopreventive ability of dietary columbin against chemically induced colon tumorigenesis when fed during the initiation phase, providing a scientific basis for chemopreventive ability of columbin against human colon cancer.

Hepatocellular carcinoma complicating biliary cirrhosis caused by biliary atresia : report of a case

A case of hepatocellular carcinoma complicating biliary cirrhosis caused by biliary atresia is reported. The patient had persistent severe jaundice with hepatosplenomegaly. A liver tumor was suspected because of the elevated serum alpha-fetoprotein and was shown by ultrasonography at 6 years of age. The tumor was treated with percutaneous ethanol injection therapy (PEIT). Nine months after initiation of PEIT, the patient died of massive bleeding from a metastatic tumor.

Intrasplenic pancreatic pseudocyst : a case report

SummaryAn intrasplenic psudocyst associated with the acute relapsing phase of chronic pancreatitis in a 51-year-old woman is reported, with a review of the Japanese literature. The patient was admitted with a complaint of left lateral and back pain. Abdominal US and CT revealed communicating cysts at the pancreatic tail and the subcapsule of the spleen. A repeat US and CT 1 month after admission demonstrated enlargement of the cyst at the pancreatic tail. ERCP revealed a dilated main pancreatic duct without any definite evidence of stenosis, and direct communication with the cyst at the pancreatic tail. Percutaneous cystography revealed that the subcapsular cyst of the spleen, the cyst of the pancreatic tail, and the main pancreatic duct communicated with each other. The cyst contained serous fluid with an amylase content of 57,500 IU/I. Distal pancreatectomy and splenectomy was performed. Histologically, there was a nonepithelial lining on the inner surface of the cysts at the pancreatic tail and the subcapsule of the spleen. Severe chronic inflammatory changes were present in the resected tail of the pancreas. Timely surgical treatment is advocated to reduce the mortality and morbidity associated with complications of intrasplenic pseudocysts.

Isolation and characterization of a low metastatic variant from EL-4 mouse T-lymphoma

A variant cell line (EL-4ad) which adhered to a tissue culture dish was isolated from highly metastatic EL-4 murine T-lymphoma. The experimental and spontaneous metastatic ability of EL-4ad was lower than that of the EL-4 parent cell line. The cell surface phenotypes of both cell lines were CD2+3+4−8− 45+TCRαβ+TCRγδ−, but the level of CD2 expression of EL-4ad was much lower than that of EL-4. Furthermore, EL-4ad had higher binding ability to fibronectin and expressed more PNA receptors on the cell surface than EL-4. These differences indicated that either the maturation stage of the less metastatic variant was lower than that of the parent cell line or the activation state of the two cell lines differed. EL-4ad showed higher in vitro invasiveness and adhesiveness to liver cells, and these characters were not consistent with the reduced metastatic ability of this variant. Neuraminidase-releasable cell surface sialic acid levels did not differ significantly between the cell lines. Neither cell line was adhesive to laminin, type IV collagen or reconstituted basement membrane. These metastasis-related properties could not explain the decreased metastatic ability of EL-4ad. On the other hand, EL-4ad was more sensitive to NK activity than EL-4 in vivo, and this was thought to be a major cause of its decreased metastasic ability. The molecules or mechanisms involved in the differentiation or activation of T-cells may be responsible for the sensitivity of tumor cells to NK activity.

Inhibition of metastasis by a dialysable factor in fetal bovine serum in B16 melanoma cells

Fetal bovine serum (FBS) supplemented to the culture medium inhibited the metastasis of B16BL6 melanoma cells in a dose-dependent manner. This metastasis-inhibiting activity was accompanied by growth-promoting activity, up to the concentration of 10% FBS. However, among the clones isolated from B16BL6 cells, there were clones in which FBS significantly inhibited the metastasis without promoting their growth. Dialysis (cutoff M.W. 8000 Da) removed the metastasis-inhibiting activity but not the growth-promoting activity from FBS. These results indicate that FBS has metastasis-inhibiting activity which is independent of growth-promoting activity, and that the metastasis-inhibiting activity is carried by molecules removed by dialysis.

Cell membrane changes of structure and function in protein kinase inhibitor-induced polyploid cells.

Exogenous cyclic AMP has been thought to be a chemical without marked pharmacological effect until now, as it is not capable of penetrating the cell membrane in most eucaryotic cells. The present study obtained results consistent with those of most previous studies, showing that exogenous cyclic AMP itself did not interfere with the cell cycle even at the high dose of 100 μM. However, it was found that K252a, a potent inhibitor of protein kinases including protein kinase C, induced DNA re‐replication, i.e. DNA synthesis at a elevated DNA ploidy in cells that had not undergone cytokinesis (leading to polyploidization), and that exogenous cyclic AMP markedly potentiated the K252a‐induced polyploidization at a very low dose similar to the effective dose of membrane‐permeable cyclic AMP analogue dibutyryl cyclic AMP. These findings suggested that the cell membrane changed during the formation of polyploid cells. This supposition was confirmed by scanning electron microscopy to observe structural changes and by determination of cellular attachment to investigate functional changes.

Decrease of metastatic ability after selection for intravasating ability in Lewis lung carcinoma (3LL) cell line

The release of cancer cells from the primary site and penetration into blood vessels are obligatory preliminary steps for metastasis. To investigate the mechanism of such steps we isolated variant cells (designated as Int-3LL) possessing enhanced intravasating ability from Lewis lung carcinoma (3LL) cells by in vivo selection. In spite of the enhanced intravasating ability of Int-3LL, the spontaneous and experimental metastatic abilities of Int-3LL decreased significantly compared to parent cells. Such a cell line has never been reported so far. The matched pair of cell lines described in this report provides a useful system for investigating the primary steps of metastasis.