Tumor progression has been recognized as the product of evolving crosstalk between cancer cells and the surrounding stromal cells. Cancer‐associated orthotopic myofibroblasts may be linked to the ...progression of gastric carcinomas. To understand the significance of orthotopic myofibroblasts, we examined the effects of cancer‐associated orthotopic myofibroblasts on the malignant phenotype of gastric cancer cells. Three human gastric cancer cell lines (OCUM‐2MD3, OCUM‐12, MKN‐45) and four human gastric fibroblast cell lines (cancer‐associated orthotopic fibroblast CaF‐29, CaF‐33, normal orthotopic fibroblast NF‐29, NF‐33) were used. The cancer‐associated orthotopic fibroblast cell lines CaF‐29 and CaF‐33 were established from a tumoral gastric wall, and normal orthotopic fibroblast NF‐29 and NF‐33 were established from a non‐tumoral gastric wall. Fibroblasts that were α‐smooth muscle actin‐positive were defined as myofibroblasts. We examined the effects of cancer‐associated orthotopic myofibroblasts on the aggressiveness of gastric cancer cells by wound‐healing assay, invasion assay, and RT‐PCR. The ratios of myofibroblasts in CaF‐29 (33%) and CaF‐33 (46%) were significantly (P < 0.001) greater than those in NF‐29 (11%) or NF‐33 (13%). Although all four orthotopic fibroblast lines increased the motility of gastric cancer cells, including migration and invasion ability, the motility‐stimulating activity of cancer‐associated fibroblasts (CaF‐29 and CaF‐33) was significantly higher than that of normal fibroblasts (NF‐29 and NF‐33). These motility‐stimulating activities of cancer‐associated orthotopic fibroblasts were downregulated by Smad2 siRNA treatment and anti‐transforming growth factor‐β neutralizing antibody. These findings suggest that cancer‐associated orthotopic myofibroblasts may play an important role in the progression of gastric cancers and that transforming growth factor‐β produced by myofibroblasts may be one of the factors associated with the aggressiveness of gastric carcinoma cells. (Cancer Sci 2012; 103: 797–805)
Epithelial mesenchymal transition (EMT) is considered to be correlated with malignancy of cancer cells and responsible for cancer invasion and metastasis. We previously reported that distant ...metastasis was associated with hypoxia in gastric cancer. We therefore investigated the effect of hypoxic condition on EMT of gastric cancer cells. Gastric cancer cells were cultured in normoxia (21% O2) or hypoxia (1% O2) for 24 h. EMT was evaluated as the percentage of spindle-shaped cells in total cells. Effect of transforming growth factor β1 (TGFβ1) or tyrosine kinase inhibitors on the EMT was evaluated. The expression level of TGFβ1 and TGFβR was evaluated by real time RT-PCR. The TGFβ1 production from cancer cells was measured by ELISA. Hypoxia stimulated EMT of OCUM-2MD3 and OCUM-12 cells, but not that of OCUM-2M cells. The expression level of TGFβ1 mRNA under hypoxia was significantly higher than that under normoxia in all of three cell lines. The expression level of TGFβR mRNA was significantly increased by hypoxia in OCUM-2MD3 cells, but not in OCUM-2M cells. TGFβR inhibitor, SB431542 or Ki26894, significantly suppressed EMT of OCUM-2MD3 and OCUM-12. TGFβ1 production from OCUM-2MD3 and OCUM-12 cells was significantly increased under hypoxia in comparison with that under normoxia. These findings might suggest that hypoxia stimulates the EMT of gastric cancer cells via autocrine TGFβ/TGFβR signaling.
Vascular endothelial growth factor receptors (VEGFRs) are mainly expressed by endothelial cells, but they are also expressed by some cancer cells, including pancreatic cancer. The objective of this ...study was to evaluate the significance of VEGFRs expression in pancreatic cancer cells. A total of 107 primary pancreatic tumors were stained with antibodies against VEGFR‐1, VEGFR‐2, phospho‐VEGFR‐2 (pVEGFR‐2), VEGFR‐3, VEGF‐A, VEGF‐C, and VEGF‐D. VEGFR‐2 and pVEGFR‐2 expression were positive in 74 (69%) and 54 (50%) of 107 pancreatic cancers. There was a significant correlation (P < 0.001) between VEGFR‐2 expression and pVEGFR‐2 expression. pVEGFR‐2 was significantly associated with invasion to the anterior capsule of pancreas (P = 0.032) and arterial invasion (P = 0.012). In contrast, VEGFR‐1 and VEGFR‐3 expression was only observed in 13 (12%) and 15 (14%) of 107 pancreatic cancers, and was not associated with any clinicopathological features. The prognosis of pVEGFR‐2 positive patients with stage IIA tumors was significantly (P = 0.0441) poorer than that of pVEGFR‐2‐negative patients. VEGF‐A, VEGF‐C, and VEGF‐D expression was positive in 42 (39%), 82 (77%), and 39 (36%) of 107 pancreatic cancers, respectively. The prognosis for VEGF‐A‐positive patients was significantly (P = 0.0425) poor, but not for VEGF‐C‐positive and VEGF‐D‐positive patients. A multivariate analysis indicated pVEGFR‐2 expression to be an independent prognostic factor, but not VEGF‐A. These findings suggested that VEGFR‐2 signaling might therefore be associated with the prognosis of patients with pancreatic cancer. The expression of pVEGFR‐2 might be a novel predictive prognostic marker for patients with pancreatic cancers, especially at clinical stage IIA. (Cancer Sci 2010)
Cancer‐associated fibroblasts (CAFs) have recently been implicated in tumor growth and metastasis in gastric cancer. Cancer stem cells (CSCs) have been proposed to have an important role in cancer ...progression. The aim of this study was to clarify the effect of CAFs on CSCs characteristics in gastric carcinoma. Scirrhous gastric cancer cell lines, OCUM‐12 and OCUM‐2MD3, and non‐scirrhous gastric cancer cell lines, MKN‐45 and MKN‐74, were used. OCUM‐12/side population (SP) cells and OCUM‐2MD3/SP cells were sorted by flow cytometry as CSC‐rich cells from the parent cells. CaF‐37 was established from the tumoral gastric specimens as CAFs. Flow cytometric analysis of SP fraction, spheroid colony assay, and RT‐PCR analysis of CSC markers were performed to identify CSCs properties. Effect of CAFs on the tumorigenicity by OCUM‐12/SP cells was examined using nude mice. CAF CM significantly increased the percentages of the SP fraction of OCUM‐12/SP and OCUM‐2MD3/SP cells, but not that of MKN‐45/SP and MKN‐74/SP cells. Taken together, CM from CaF‐37 significantly increased the number of spheroid colonies and the expression level of CSC markers of OCUM‐12/SP and OCUM‐2MD3/SP cells. These stimulating‐activities by CM were significantly decreased by TGFβ inhibitors, but not FGFR and cMet inhibitor. Tumorigenicity by subcutaneous coinoculation of OCUM‐12/SP cells with CAFs was significantly high in comparison with that by OCUM‐12/SP cells alone. Phospho‐Smad2 expression level was significantly increased by co‐inoculation with CAFs. These findings suggested that CAFs might regulate the stemness of CSCs in scirrhous gastric cancer by TGFβ signaling.
What's new?
Stem cells, such as embryonic stem cells and induced pluripotent stem cells, require fibroblasts as feeder cells, but it is unclear whether cancer stem cells have the same requirement. This study shows that cancer‐associated fibroblasts sustain the stemness of the scirrhous‐type of gastric cancer cells. Scirrhous gastric cancer is characterized by cancer cell proliferation accompanied by extensive stromal fibrosis. The authors find that transforming growth factor β (TGFβ) produced by fibroblasts increased spheroid formation and expression levels of cancer stem cell markers in cancer stem cells, a process inhibited by inhibitors of TGFβ signaling. Targeting the TGFβ signaling pathway might thus be a promising strategy to interfere with scirrhous‐type gastric carcinoma.
Vimentin expression in epithelial cells is reported to be associated with the malignant phenotype of cancer cells in vitro. However, the clinical significance of vimentin expression in carcinomas is ...not well understood. The aim of this study was to clarify the significance of vimentin-positive gastric cancer (GC).
A total of 265 GCs were examined by immunofluorescent staining with antibodies against vimentin and carcinoembryonic antigen. GCs were determined to be vimentin-positive when cells were positive for both vimentin and carcinoembryonic antigen staining.
A total of 86 (32%) of 265 GCs were vimentin positive. There was a statistically significant correlation between vimentin-positive GCs and advanced clinical stage (p<0.001), macroscopic scirrhous-type (p < 0.001), histological diffuse-type (p < 0.001), lymph node metastasis (p = 0.008) and lymphatic invasion (p = 0.013). The prognosis of patients with vimentin-positive GCs was significantly (p < 0.001) worse than that with vimentin-negative GCs.
Vimentin expression might contribute to the high invasive phenotype of GC, and may be a useful biomarker to determine the biological aggressiveness of GC.
The aim of this study was to examine the effects of hypoxia on radiosensitivity and to analyze the mechanisms responsible for radiation resistance in gastric and esophageal cancer.
A gastric cancer ...cell line, OCUM-12, and an esophageal cancer cell line, TE-6, were used. The effects of hypoxia with irradiation on the growth-activity, cell cycle distribution, and gene expression were examined.
Both acute and chronic hypoxia decreased radiosensitivity of cancer cells. The radiosensitivity of chronic hypoxic cells was significantly enhanced by reoxygenation. Acute and chronic all hypoxia reduced the percentage of cells in the G(2)/M and S phases, respectively. In acute hypoxia, the mRNA expression of BRCA1 and BRCA2 was reduced in cancer cells. Reoxygenation increased the expression of BRCA1 and BRCA2.
Hypoxia is associated with radiation resistance. Therefore, reoxygenation may enhance the radiosensitivity of hypoxic cells. BRCA1 and BRCA2 may be associated with factors for radiation resistance by regulation of cell cycle progression.
Cancer-associated fibroblasts (CAFs) have recently been implicated in tumor growth and metastasis in gastric cancer. Cancer stem cells (CSCs) have been proposed to have an important role in cancer ...progression. The aim of this study was to clarify the effect of CAFs on CSCs characteristics in gastric carcinoma. Scirrhous gastric cancer cell lines, OCUM-12 and OCUM-2MD3, and non-scirrhous gastric cancer cell lines, MKN-45 and MKN-74, were used. OCUM-12/side population (SP) cells and OCUM-2MD3/SP cells were sorted by flow cytometry as CSC-rich cells from the parent cells. CaF-37 was established from the tumoral gastric specimens as CAFs. Flow cytometric analysis of SP fraction, spheroid colony assay, and RT-PCR analysis of CSC markers were performed to identify CSCs properties. Effect of CAFs on the tumorigenicity by OCUM-12/SP cells was examined using nude mice. CAF CM significantly increased the percentages of the SP fraction of OCUM-12/SP and OCUM-2MD3/SP cells, but not that of MKN-45/SP and MKN-74/SP cells. Taken together, CM from CaF-37 significantly increased the number of spheroid colonies and the expression level of CSC markers of OCUM-12/SP and OCUM-2MD3/SP cells. These stimulating-activities by CM were significantly decreased by TGFbeta inhibitors, but not FGFR and cMet inhibitor. Tumorigenicity by subcutaneous coinoculation of OCUM-12/SP cells with CAFs was significantly high in comparison with that by OCUM-12/SP cells alone. Phospho-Smad2 expression level was significantly increased by co-inoculation with CAFs. These findings suggested that CAFs might regulate the stemness of CSCs in scirrhous gastric cancer by TGFbeta signaling. What's new? Stem cells, such as embryonic stem cells and induced pluripotent stem cells, require fibroblasts as feeder cells, but it is unclear whether cancer stem cells have the same requirement. This study shows that cancer-associated fibroblasts sustain the stemness of the scirrhous-type of gastric cancer cells. Scirrhous gastric cancer is characterized by cancer cell proliferation accompanied by extensive stromal fibrosis. The authors find that transforming growth factor beta (TGFbeta) produced by fibroblasts increased spheroid formation and expression levels of cancer stem cell markers in cancer stem cells, a process inhibited by inhibitors of TGFbeta signaling. Targeting the TGFbeta signaling pathway might thus be a promising strategy to interfere with scirrhous-type gastric carcinoma.
Gastric cancers are characterized by a heterogeneously hypoxic environment. Hypoxia might stimulate the malignant potential of cancer cells. The purpose of our study was to clarify the significance ...of hypoxia in gastric carcinoma by evaluating the expression of a hypoxic marker, namely carbonic anhydrase-9 (CA-9).
A total of 265 patients who had undergone a resection of the primary tumor and were confirmed histologically to have sporadic gastric cancer were enrolled in this study. We evaluated the immunohistochemical expression of CA-9 in the paraffin-embedded specimens of 265 gastric adenocarcinomas.
The CA-9 expression was positive in 88 (33%) of 265 gastric carcinomas. The CA-9 expression level was significantly high in cases of type 4 carcinoma (60%, p < 0.001) and diffuse type carcinoma (41%, p < 0.001), and significantly correlated with the invasion depth (p < 0.001), lymph node metastasis (p < 0.001) and lymphatic invasion p = 0.002). The prognosis for CA-9-positive patients was significantly poorer than that of CA-9-negative patients (p = 0.003, log-rank).
Hypoxia might be associated with aggressive tumor phenotypes of gastric carcinomas. The hypoxic marker CA-9 may be a useful prognostic indicator.
A Resected Case of Biliary Cystadenocarcinoma Ako, Eiji; Yoshii, Mami; Fuyuhiro, Yuhiko ...
Nippon Shokaki Geka Gakkai zasshi,
2008, 2008-00-00, Letnik:
41, Številka:
6
Journal Article
Odprti dostop
A-72-year-old man admitted for examination of a liver cyst seen in a physical health screening was found in abdominal computed tomography (CT) to have a cystic tumor 5cm in diameter having a ...contrast-enhanced papillary projection 2cm in diameter arising from the cystic wall in the S4 segment of the liver. Abdominal T1-weighted magnetic resonance imaging (MRI) showed a low-intensity lesion and T2-weighted MRI a highintensity lesion. Drip infusion cholangiography (DIC)-CT suggested that the tumor might not be connected to the intrahepatic bile duct. Abdominal angiography showed tumor staining in the S4 segment of the liver, indicative of the solid portion in the cystic tumor. Based on a diagnosis of biliary cystadenocarcinoma, we conducted left hepatectomy and cholecystectomy. The resected specimen showed a unilocular cystic tumor with a papillary projection inside. The cystic tumor was diagnosed as biliary cystadenocarcinoma on histological examination, and the entire cystic wall showed the presence of cancer cells. Segmental hepatectomy including the cystic tumor provides the most favorable prognosis for biliary cystadenocarcinoma.
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