Search

The air-liquid interface (ALI) is a common microenvironment of the skin, but it is unknown whether the ALI affects melanoma cell behaviors. Using a collagen gel invasion assay, immunohistochemistry, and Western blots, here we show that melanoma cell proliferation in cultures with an ALI is higher than melanoma cell proliferation in submerged cultures. Bromodeoxyuridine (BrdU) uptake, an indicator of cell proliferation, of melanoma cells at the ALI was about 3 times that of submerged cells, while ALI and submerged melanoma cells had similar levels of single-stranded DNA (a marker of apoptosis). The ALI enhanced the expression of Raf-1, MEK-1 and pERK-1/2 components of the mitogen-activated protein kinase (MAPK) cascade, in cells more than the submerged condition did. The increases in BrdU uptake and pERK-1/2 expression promoted by ALI was abolished by the MEK inhibitor, PD-98059. ALI-treated and submerged melanoma cells did not infiltrate into the collagen gel, and they showed no significant difference in the expression of the invasion- and motility-related molecules, matrix metalloproteinase-1 and -9, laminin 5, and filamin A. Our data indicate that the ALI, a skin microenvironment, accelerates the growth, but not the apoptosis or invasion, of melanoma cells through MAPK activation.

Air-liquid interface (ALI) is a microenvironment of aerodigestive tract. In our previous study, ALI promoted invasive growth of laryngeal squamous cell carcinoma (SCC); but its mechanism was unclear. Hypoxia is also related to cancer spread. Here we show that ALI with or without hypoxia accelerated invasive growth of laryngeal SCC cells, using collagen gel invasion assay. Submerged condition (SMC) without ALI did not induce the invasion with or without hypoxia. ALI enhanced expression of the following growth-, invasion-, and motility-related molecules in the cells with or without hypoxia more greatly than SMC: c-Met, Ras, mitogen-activated protein kinase cascade proteins (Raf-1, MEK-1, and ERK-1/2), matrix metalloproteinase-1, and filamin A. The data indicate that ALI promotes invasive growth of SCC cells by enhancement of the invasive growth-related molecules above, through mechanisms that differ from hypoxia, suggesting that ALI microenvironment should be taken into account for the study of cancer biology.

論文(Article), Mesenchymal cell types, under mesenchymal-epithelial interaction, are involved in tissue regeneration. Here we show that bone marrow stromal cells (BMSCs), subcutaneous preadipocytes, and dermal fibroblasts distinctively caused keratinocytes to promote epidermal regeneration, using a skin reconstruction model by their coculture with keratinocytes. Three mesenchymal cell types promoted the survival, growth, and differentiation of keratinocytes, whereas BMSCs and preadipocytes inhibited their apoptosis. BMSCs and preadipocytes induced keratinocytes to reorganize rete ridge- and epidermal ridge-like structures, respectively. Keratinocytes with fibroblasts or BMSCs expressed the greatest amount of interleukin (IL)-1alpha protein, which is critical for mesenchymal-epithelial cross-talk in skin. Keratinocytes with or without three mesenchymal supports displayed another cross-talk molecule, c-Jun protein. Without direct mesenchymal-epithelial contact, the rete ridge- and epidermal ridge-like structures were not replicated, whereas the other phenomena noted above were. DNA microarray analysis showed that the mesenchymal-epithelial interaction affected various gene expressions of keratinocytes and mesenchymal cell types. Our results suggest that not only skin-localized fibroblasts and preadipocytes but also BMSCs accelerate epidermal regeneration in complexes and that direct contact between keratinocytes and BMSCs or preadipocytes is required for the skin-specific morphogenesis above, through mechanisms that differ from the IL-1alpha/c-Jun pathway.

A 79-year-old man was referred to this department due to the presence of extrahepatic bile duct carcinoma with a tumor at the left chest wall. The lesion was suspected to be a metastasis of bile duct carcinoma to the left wall, however, computed tomography (CT) revealed no regional lymph node or liver metastases. In addition, cytological and pathological examinations did not show malignancy. At the time of admission, the white blood cell count was 21 460 cells/μL (neutrophils, 18 240 cells/μL) and this elevated to 106 040 before death. In addition, serum granulocyte colony-stimulating factor (G-CSF) was elevated. At 28 d after admission, the patient died. An autopsy showed a poorly differentiated adenocarcinoma with sarcomatous change, which had slightly invaded into the pancreas around the bile duct, and was found in the distal bile duct with multiple metastases to the chest wall, lung, kidney, adrenal body, liver, mesentery, vertebra and mediastinal and para-aortic lymph nodes, without locoregional lymph node and liver metastasis. The cancer cells showed positive immunohistochemical staining for anti-G-CSF antibody. This is believed to be the first report of an extrahepatic bile duct carcinoma that produces G-CSF. Since G-CSF-producing carcinoma and sarcomatous change of the biliary tract leads to poor prognosis, early diagnosis and treatment are needed. When infection is ruled out, the G-CSF in serum should be examined. In addition, examinations such as bone scintigraphy and chest CT should also be considered for distant metastasis.

To obtain immature fat cells in vitro, we used a primary culture of undigested mature fat tissue fragments. The immature fat cells, i.e., fibroblast-like fat cells, proliferated extensively from the fat tissue and differentiated after reaching confluence. The process of differentiation was assumed by the development of intracytoplasmic lipid droplets and by the triglyceride content in the cells. Cellular differentiation was induced in high percentages (over 70-80%) of the cells in the medium containing high glucose concentrations (200 mg/dl) supplemented with 10-20% newborn calf serum. The intracellular accumulation of triglyceride was also enhanced by insulin administration. In these cells, a reciprocal relationship was observed between proliferation and differentiation. Fibroblast-like fat cells derived from mature fat tissue in this simple culture system are suitable for the study of the proliferation and differentiation of immature fat cells.

Three-dimensional culture with collagen gel, developed recently for the in vitro study of some mammalian cells in a more physiological condition than a monolayer culture, was applied for a biological study of unilocular fat cells. Successfully embedded in the gel, the unilocular fat cells were shown to be able to keep their cellular function and actively proliferate. These findings confirm that unilocular fat cells do undergo proliferation under in vitro conditions as demonstrated in monolayer culture.

Effects of several conditions known to stimulate the zona glomerulosa of the adrenal cortex in the adult were examined on the fetal adrenal cortex of rats histochemically and electron microscopically. The stimulating conditions were the following; administration of Na restricted diet to the mother, administration of KCl or angiotensin II to the fetus, spironolactone or insulin to the mother. In these, only an intraperitoneal injection of KCl solution to the fetus affected the fetal zona glomerulosa, in which increased activity of glucose-6-phosphate dehydrogenase and hyperfunctional alteration of the mitochondria and the smooth endoplasmic reticulum were observed. This fact shows the fetal glomerulosa cells can react to orae of the specific stimuli on the adult glomerulosa cells., Acta Histochemica et Cytochemica, 13(4), pp.324-329; 1980

Recently it has been stressed that catecholamines play a significant role in the pathogenesis of hypertension in Spontaneously Hypertensive Rats (Okamoto and Aoki) (SHR). In this report electron microscopical observation in male SHR was made on the adrenal medulla through the processes of the hypertension. The mild hyperfunctional state of norepinephrine-secreting cells in the initial stage of hypertension was expected on the feature of increased population of norepinephrine-secreting cells, its prominent Golgi complex and rough-surfaced endoplasmic reticulum and increased degranulation in the cell. Moreover, it may be assumed a certain functional change of epinephrine-secreting cell system on the base of increased population of dark epinephrine-secreting cells which are regarded as premature cells., Acta Histochemica et Cytochemica, 5(1), pp.39-44; 1972

Cancer cell-stromal cell interaction plays a crucial role in the malignant growth of cancer cells. In the skin, the main stromal cell types consist of dermal fibroblasts and subcutaneous adipocytes. Fibroblasts are shown to promote the invasive growth of various cancer cell types. The interaction between cancer cells and stromal adipocytes, however, has not been sufficiently studied even in cutaneous carcinoma. To address the effects of adipocytes on the biologic behavior of cancer cells, we examined the growth and differentiation of a squamous cell carcinoma cell line of the skin (DJM-1), using a three-dimensional collagen gel matrix culture with a cutaneous environmental factor, air exposure. The growth was estimated by the uptake of bromodeoxy-uridine (BrdU) for 24 h. The BrdU indices of DJM-1 cells in stromal-cell-free, fibroblast-containing, and adipocyte- containing conditions were 19.7 +/- 1.9%, 19.8 +/- 2.8%, and 4.7 +/- 1.4%, respectively, whereas the BrdU index on the gel containing both fibroblasts and adipocytes was 10.4 +/- 3.3%. In terms of differentiation, DJM-1 cells cocultured with adipocytes constructed the best-organized stratified layer with a cornified-like structure in all conditions above. The differentiation markers involucrin and cytokeratin 10 were immunohistochemically detected in this structure of DJM-1 cells. Adipocyte-induced phenomena were not affected distinctively by air exposure. These results indicate that adipocytes, but not fibroblasts, promote the differentiation of squamous cell carcinoma cells (DJM-1) and inhibit their growth. These adipocyte-induced phenomena were not completely inhibited by fibroblasts. In conclusion, we suggest that stromal adipocytes may be involved in the differentiating mechanisms of cutaneous carcinoma cells.