Yoshitomo Koshida

Kitasato University, Edo, Tōkyō, Japan

Are you Yoshitomo Koshida?

Claim your profile

Publications (2)5.35 Total impact

  • Yoshitomo Koshida, Masaru Kuranami, Masahiko Watanabe
    [Show abstract] [Hide abstract]
    ABSTRACT: Vascular endothelial growth factor (VEGF), a potent angiogenic factor, has been implicated in metastasis of colorectal cancer (CRC). The present study aimed to clarify whether cancer-stromal interaction induces the production of VEGF. Human colonic fibroblasts (CCD-18Co) and CRC (SW480, SW620) cells were analyzed in this study. The cell cycle of colonic fibroblasts during co-culture was analyzed by flow cytometry. VEGF and TGF-beta1 released into the conditioned media in co-culture models were measured. Northern blot with human specific VEGF probe was performed to identify the expression of VEGF in this model. Co-culture of colonic fibroblasts with CRC cells increased the viability of fibroblasts during co-culture. Cell cycle analysis revealed that most of the fibroblasts co-cultured with CRC cells were arrested at G1 phase and few cells were in sub-G1 phase that indicates apoptosis. Although VEGF protein was detected in the culture media of all of the monocultures, co-cultivation of CRC with fibroblasts resulted in synergistic increase of VEGF production compared with monocultures. However TGF-beta1 protein was not detected in any conditioned medium. VEGF mRNA was detected in both CRC and fibroblasts. Under co-culture condition, an abundance of VEGF mRNA expression was noted in fibroblasts relative to CRC cells. The present study suggests that CRC manipulates the host stroma to suppress apoptosis and up-regulate VEGF production.
    Journal of Surgical Research 09/2006; 134(2):270-7. · 2.02 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Platelet-derived endothelial cell growth factor, identified to be an angiogenic factor, has been implicated in metastases of colorectal cancer. This study aimed to clarify the role and localization of platelet-derived endothelial cell growth factor associated with human colorectal cancer invasion. Thirty-two patients with colorectal cancer who had undergone surgery were analyzed. Platelet-derived endothelial cell growth factor enzyme activities in the colorectal cancer specimens were measured. Cells that expressed platelet-derived endothelial cell growth factor were identified and localized by immunohistochemical analysis with anti-human platelet-derived endothelial cell growth factor antibody and by in situ hybridization with specific RNA probe. Platelet-derived endothelial cell growth factor enzyme activity increased significantly in cancer tissues compared with normal colonic mucosa at various distances from the cancer. Immunohistochemical analysis and in situ hybridization demonstrated platelet-derived endothelial cell growth factor expression in stromal macrophages and fibroblasts located in cancer tissues and surrounding noncancerous tissues, although the tumor cells and normal colonic mucosa were negative. The value of platelet-derived endothelial cell growth factor expression was highest at the border of the colorectal cancer (35.3 +/- 8.9 percent), followed by the cancer nest (15.2 +/- 9.2 percent) and normal mucosa (7.7 +/- 3.4 percent). In the border area, the highest value of platelet-derived endothelial cell growth factor expression was observed in the submucosa (35.3 +/- 8.9 percent), followed by the muscular propria (21.9 +/- 7.7 percent) and the subserosa (14.9 +/- 5.5 percent). Stromal macrophages and fibroblasts are responsible for elevated platelet-derived endothelial cell growth factor activity in colorectal cancer. The significance of enhanced expression of platelet-derived endothelial cell growth factor in the submucosa at the cancer border remains unclear. Cancer stroma may be an important factor for cancer angiogenesis and may serve as a treatment target through specific modulation of angiogenic factors.
    Diseases of the Colon & Rectum 01/2005; 47(12):2093-100. · 3.34 Impact Factor