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

Abstract

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.

Significance of the Lysyl Oxidase Members Lysyl Oxidase Like 1, 3, and 4 in Gastric Cancer

“…Five gastric cancer cell lines, OCUM-2M [24,25], OCUM-2MLN [26], OCUM-2MD3 [27], OCUM-12 [28], and KATO-III derived from diffuse-type gastric carcinomas, were used. After these cell lines were authenticated by STR profiling before distribution to eliminate contamination, we cryopreserved them up to 5th passage.…”

Lysyl oxidase is associated with the epithelial–mesenchymal transition of gastric cancer cells in hypoxia

“…We used two gastric cancer cell lines, OCUM-2MD3 [38] and OCUM-12 [39], derived from diffuse-type gastric carcinomas. The culture medium consisted of Dulbecco's modified Eagle's medium (DMEM; Wako, Osaka, Japan) with the addition of 10 % fetal bovine serum (FBS; Nichirei., Tokyo, Japan), 100 IU/ml penicillin (Wako), 100 mg/ml streptomycin (Wako), and 0.5 mM sodium pyruvate (Wako).…”

The Critical Impact of HIF-1a on Gastric Cancer Biology

“…Kato et al . investigated the abilities of cancer invasion and metastasis in hypoxia-resistant scirrhous gastric cancer cells [24]. The authors demonstrated that several markers related to epithelial mesenchymal transition (EMT) such as Snail, Twist, ZEB and Vimentin are upregulated in hypoxia-resistant cells compared with that observed in parental cells.…”

“…The authors demonstrated that several markers related to epithelial mesenchymal transition (EMT) such as Snail, Twist, ZEB and Vimentin are upregulated in hypoxia-resistant cells compared with that observed in parental cells. Indeed, the resistant cells demonstrated increased invasion abilities in vitro and exhibited morphological changes to a spindle-shape compared with the parental cells [24]. Furthermore, the authors showed that the hypoxia-resistant cells, but not the parental cells, developed multiple metastases to the peritoneum and lymph nodes in mice [24].…”