Upregulation of cancer-associated myofibroblasts by TGF-ß from scirrhous gastric carcinoma cells.

BACKGROUND: Myofibroblasts in the cancer microenvironment have recently been implicated in tumour growth and metastasis of gastric cancer. However, the mechanisms responsible for the regulation of myofibroblasts in cancer-associated fibroblasts (CAFs) remain unclear. This study was performed to clarify the mechanisms for regulation of myofibroblasts in gastric cancer microenvironment. METHODS: Two CAFs (CaF-29 and CaF-33) from the tumoural gastric wall and a normal fibroblast (NF-29) from the nontumoural gastric wall, 4 human gastric cancer cell lines from scirrhous gastric cancer (OCUM-2MD3 and OCUM-12), and non-scirrhous gastric cancer (MKN-45 and MKN-74) were used. Immunofluorescence microscopy by triple-immunofluorescence labelling (α-SMA, vimentin, and DAPI) was performed to determine the presence of α-SMA-positive myofibroblasts. Real-time RT-PCR was performed to examine α-SMA mRNA expression. RESULTS: Immunofluorescence microscopy showed that the frequency of myofibroblasts in CaF-29 was greater than that in NF-29. The number of myofibroblasts in gastric fibroblasts gradually decreased with serial passages. Transforming growth factor-ß (TGF-ß) significantly increased the α-SMA expression level of CAFs. Conditioned medium from OCUM-2MD3 or OCUM-12 cells upregulated the α-SMA expression level of CAFs, but that from MKN-45 or MKN-74 cells did not. The α-SMA upregulation effect of conditioned medium from OCUM-2MD3 or OCUM-12 cells was significantly decreased by an anti-TGF-ß antibody or Smad2 siRNA. CONCLUSION: Transforming growth factor-ß from scirrhous gastric carcinoma cells upregulates the number of myofibroblasts in CAFs.

Establishment and characterization of a new hypoxia-resistant cancer cell line, OCUM-12/Hypo, derived from a scirrhous gastric carcinoma.

BACKGROUND: Many kinds of solid tumour have heterogeneously a hypoxic environment. Tumour hypoxia reported to be associated with more aggressive tumour phenotypes such as high metastatic ability and resistance to various anti-cancer therapies which may lead to a poorer prognosis. However, the mechanisms by which hypoxia affects the aggressive phenotypes remain unclear. METHODS: We established a scirrhous gastric carcinoma cell line (OCUM-12) from ascites associated with scirrhous gastric carcinoma, and a hypoxia-resistant cancer cell line (OCUM-12/Hypo) was cloned from OCUM-12 cells by continuous exposure to 1% oxygen. RESULTS: Histologic findings from orthotopic tumours derived from parent OCUM-12 cells and daughter OCUM-12/Hypo cells revealed poorly differentiated adenocarcinoma with extensive fibrosis that resembled human scirrhous gastric cancer. Necrotic lesions were frequently detected in the OCUM-12 tumours but were rarely found in the OCUM-12/Hypo tumours, although both types had multiple hypoxic loci. Apoptosis rate of OCUM-12 cells was increased to 24.7% at 1% O(2), whereas that of OCUM-12/Hypo was 5.6%. The OCUM-12/Hypo orthotopic models developed multiple metastases to the peritoneum and lymph nodes, but the OCUM-12 models did not. OCUM-12/Hypo cells showed epithelial-to-mesenchymal transition and high migratory and invasive activities in comparison with OCUM-12 cells. The mRNA expression levels of both E-cadherin and zonula occludens ZO-1 and ZO-2 decreased in OCUM-12/Hypo cells, and that of vimentin, Snail-1, Slug/Snail-2, Twist, ZEB-1, ZEB-2, matrix metalloproteinase-1 (MMP-1), and MMP-2 were increased in OCUM-12/Hypo cells. CONCLUSION: OCUM-12 and OCUM-12/Hypo may be useful for the elucidation of disease progression associated with scirrhous gastric cancer in the setting of chronic hypoxia.

[Three cases of primary malignant lymphoma of the small intestine].

Three cases of a primary malignant lymphoma of the small intestine are reported. Case 1: a 62-year-old male who underwent an emergency operation for a jejunal perforation of a malignant lymphoma (aneurysmal type, Stage III, diffuse small cell type). The patient is still alive 16 months after the operation. Case 2: A 54-year-old female with complaints of an abdominal pain and anemia was found to have three tumors (one in the jejunum, two in the ileum) that were determined as being malignant lymphomas (all of the aneurysmal type, Stage III, diffuse medium-sized cell types). This patient is still alive 11 months after the operation. Case 3: A 40-year-old male with a complaint of an abdominal pain was found to have a malignant lymphoma of the ileum (aneurysmal type, Stage III, a diffuse medium-sized cell type). This patient died on the 60th day after the operation.

Percutaneous endoscopic gastrostomy, duodenostomy and jejunostomy.

Although enteral feeding by nasal gastric tube is popular for the patients who have a swallowing disability and require long-term nutritional support, but have intact gut, this tube sometimes causes aspiration pneumonia or esophageal ulcer. For these patients, conventional techniques for performance of a feeding gastrostomy made by surgical laparotomy have been used so far. However, these patients are frequently poor anesthetic and operative risks. Percutaneous endoscopic gastrostomy (PEG) which can be accomplished with local anesthesia and without the necessity for laparotomy has become popular in the clinical treatment for these patients. PEG was performed in 31 cases, percutaneous endoscopic duodenostomy (PED) in 1 case, and percutaneous endoscopic jejunostomy (PEJ) in 2 cases. All patients were successfully placed, and no major complication and few minor complications (9%) were experienced in this procedure. After this procedure, some patients could discharge their sputa easily and their pneumonia subsided. PED and PEJ for the patients who had previously received gastrostomy could also be done successfully with great care. Our experience suggests that PEG, PED, and PEJ are rapid, safe, and useful procedures for the patients who have poor anesthetic or poor operative risks.