Ying-Jie Su

Maternal and Children Health Hospital of Guangxi Zhuang Autonomous Region, Yung-ning, Guangxi Zhuangzu Zizhiqu, China

Are you Ying-Jie Su?

Claim your profile

Publications (4)4.9 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: To investigate the effects of sphingosine kinase 1 (SphK1) on the proliferation, migration and invasion of human colon cancer LoVo cells, and to explore the related mechanisms. Human colon cancer LoVo cells were divided into three groups: phorbol 12-myristate 13-acetate (PMA) was used to induce the activation of SphK1 in the PMA group, N,N-dimethylsphingosine (DMS) used to suppress the activity of SphK1 in DMS group, and the cells treated with equal amount of 0.9 % NaCl instead of drugs served as the control group. The activity of SphK1 was assayed by autoradiography, the cell proliferation was assessed by MTT assay, cell migration and invasion were examined by Boyden chamber assay, concentrations of sICAM-1 and sVCAM-1 were assayed by ELISA, and RT-PCR and Western blot were used to evaluate the mRNA and protein expression in the cells. The activity of SphK1 was efficiently induced by PMA and significantly suppressed by DMS. PMA induced cell proliferation in a time- and dose-dependent manner. On the contrast, DMS suppressed cell proliferation in a time- and dose-dependent manner. After treating with PMA, the number of migrating and invasing cells were increased to 143.36 ± 8.73 and 118.46 ± 6.25, significantly higher than those of the control group (75.48 ± 6.12 and 64.19 ± 5.36). After treating with DMS, the number of migrating and invasing cells were decreased to 38.57 ± 3.24 and 32.48 ± 4.27, significantly lower than those of the control group (P < 0.01). The relative expression levels of FAK, ICAM-1 and VCAM-1 mRNA in the PMA group were 0.82 ± 0.06, 0.74 ± 0.05 and 0.89 ± 0.09, and those in the DMS group were 0.23 ± 0.02, 0.26 ± 0.03 and 0.37 ± 0.04, with significant differences between the PMA, DMS and control groups (P < 0.01). Compared with the control group, the relative expression levels of FAK and p-FAK proteins in the PMA group (0.52 ± 0.06 and 0.51 ± 0.06) were significantly elevated, and those of the DMS group (0.20 ± 0.03 and 0.09 ± 0.02) were significantly decreased. In addition, the concentrations of sICAM-1 and sVCAM-1 were significantly elevated with the activation of SphK1. On the contrary, those of the DMS group were significantly reduced with the suppression of SphK1 (Both P < 0.01). SphK1 may enhance the proliferation, migration and invasion of colon cancer LoVo cells through activating FAK pathway and up-regulating the expression of ICAM-1 and VCAM-1.
    Zhonghua zhong liu za zhi [Chinese journal of oncology] 05/2013; 35(5):331-6.
  • [show abstract] [hide abstract]
    ABSTRACT: Studies suggest a tumor-promoting function of sphingosine kinase 1 (SphK1) in some types of human tumors, however, its effect on colon cancer is still unclear. The aims of this study were to investigate the roles of SphK1 in the progression and tumor cell phenotypic changes in colon cancer. Moreover, the focal adhesion kinase (FAK) pathway and the expression of intercellular adhesion molecule‑1 (ICAM‑1) and vascular cell adhesion molecule‑1 (VCAM‑1) were detected to explore the mechanisms of SphK1 action. In this study, the expression of SphK1, FAK and phospho-FAK (p-FAK) was analyzed in 66 surgical specimens of primary colon cancer and matched adjacent normal tissues by immunohistochemistry and western blotting. In addition, N,N-dimethylsphingosine (DMS), SphK1 DNA and shRNA transfection were used to regulate the expression and activity of SphK1 in the LOVO colon cancer cell line. Tumor cell phenotypic changes were analyzed by cell viability, invasion and apoptosis assays. Results showed that the expression of SphK1, FAK and p-FAK in colon cancer tissues were significantly stronger compared to those in matched normal tissues. There was a close correlation between the expression of SphK1 and FAK or p-FAK and the co-expression of SphK1, FAK and p-FAK significantly associated with histological grade, Dukes' stage, lymph node metastasis and distant metastasis. Overexpression of SphK1 after DNA transfection enhanced tumor cell viability and invasiveness, but suppressed cell apoptosis. In contrast, suppression of SphK1 by DMS and shRNA reduced tumor cell viability and invasiveness, but promoted cell apoptosis. The expression of FAK, p-FAK, ICAM-1 and VCAM-1 in LOVO cells were increased with the overexpression of SphK1 but decreased with the suppression of SphK1. These findings indicate that SphK1 regulates tumor cell proliferation, apoptosis and invasion, which ultimately contributes to tumor progression and malignancy phenotype in colon cancer. FAK pathway, ICAM-1 and VCAM-1 may play critical roles in this SphK1‑mediated effect.
    International Journal of Oncology 12/2012; · 2.66 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: PURPOSE: Sphingosine kinase (SphK) 1 is an oncogenic enzyme promoting transformation, proliferation, and survival of a number of human tumor cells. However, its effect on colon cancer cell behavior has not been fully clarified. METHODS: SphK1 plasmid or SphK1 shRNA transfection and N,N-dimethylsphingosine (DMS) was used to regulate the expression and activity of SphK1 in colon cancer line LOVO. Cell proliferation, apoptosis, invasion, and protein expression were detected by MTT, flow cytometry, transwell chambers model, and western blot. The levels of metalloproteinases-2/9 (MMP-2/9) and urokinase plasminogen activator (uPA) were detected by ELISA. RESULTS: Overexpression of SphK1 after plasmid transfection markedly enhanced LOVO cell viability and invasiveness and reduced cell apoptosis. In contrast, inhibition of SphK1 by DMS and shRNA significantly suppressed cell viability and invasiveness but promoted cell apoptosis. SphK1 increased the constitutive expression of extracellular signal-regulated kinase1/2 (ERK1/2) but reduced the constitutive expression of p38 mitogen-activated protein kinase (MAPK). Blocking ERK1/2 pathway inhibited the biological effects induced by overexpression of SphK1. Blocking p38 MAPK pathway reversed the effects of DMS and SphK1 shRNA. Moreover, SphK1 was required for the production of MMP-2/9 and uPA in tumor cells, which was suppressed by ERK1/2 inhibitor U0126, but enhanced by the p38 MAPK inhibitor SB203580. CONCLUSIONS: SphK1 enhances colon cancer cell proliferation and invasiveness, meanwhile suppressing cell apoptosis. SphK1 promoting the secretion of MMP-2/9 and uPA via activation of ERK1/2 and suppression of p38 MAPK pathways maybe the molecular mechanisms for its regulation of the malignant behavior of colon cancer cell.
    International Journal of Colorectal Disease 06/2012; · 2.24 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: To investigate the expression of sphingosine kinase 1 (SphK1) and NF-κB in colon carcinoma tissues and their correlation with clinicopathologic features. Sixty-six paraffin-embedded colon carcinoma samples and 66 fresh colon carcinoma samples were tested using immunohistochemistry, RT-PCR and Western blot, respectively. In 66 fresh colon carcinoma samples, the positive rate of SphK1 and NF-κB mRNA expression were 84.85%(56/66) and 74.24% (49/66), while the positive rate of SphK1 and NF-κB protein detected by Western blot were 78.79% (52/66) and 69.70% (46/66). The positive rates were higher than those in the adjacent tissues [mRNA: 63.64% (42/66), 48.49% (32/66); protein: 57.58% (38/66), 45.45% (30/66)] and the normal mucosa [mRNA: 42.42% (28/66), 25.76% (17/66); protein: 36.36% (24/66), 24.24% (16/66)], with statistical significances (all P values < 0.05). The mean expressive levels of SphK1 and NF-κB mRNA and protein in colon carcinoma were both significantly higher than those in the adjacent tissues and the normal mucosa (mRNA: 0.55 ± 0.06 vs 0.35 ± 0.05 vs 0.25 ± 0.05, 0.75 ± 0.06 vs 0.43 ± 0.05 vs 0.30 ± 0.04; protein: 0.77 ± 0.05 vs 0.38 ± 0.06 vs 0.12 ± 0.03, 0.45 ± 0.08 vs 0.23 ± 0.05 vs 0.13 ± 0.03; all P values < 0.05). There was a close correlation between SphK1 and NF-κB expression levels (r = 0.459, P = 0.036). The results of immunohistochemistry were similar to those of RT-PCR and Western blot. Overexpression of SphK1 and NF-κB in colon carcinoma was related with depth of invasion, distant and lymph node metastasis and Dukes' stages (all P values < 0.05). The expression of SphK1 was also related with differentiation (P < 0.05). Overexpression of SphK1 and NF-κB may be involved in the pathogenesis and progression of colon carcinoma. Moreover, SphK1 and NF-κB may be correlated with the invasion and metastasis of colon carcinoma.
    Zhonghua nei ke za zhi [Chinese journal of internal medicine] 03/2012; 51(3):220-4.