AIM: To examine the expression of Sph K1, an oncogenic kinase that produces sphingosine 1-phosphate(S1P), and its correlation with the expression of LPAR2, a major lysophosphatidic acid(LPA) receptor overexpressed in various cancers, in human colorectal cancer.METHODS: Real-time reverse-transcription polymerase chain reaction was used to measure the m RNA expression of Sph K1, LPAR2, and the three major S1 P receptors in 27 colorectal cancer samples and corresponding normal tissue samples. We also examined the correlation between the expression of Sph K1 and LPAR2.RESULTS: C o l o r e c t a l c a n c e r t i s s u e i n 2 2 o f 2 7 patients had higher levels of Sph K1 m RNA than in normal tissue. In two-thirds of the samples, Sph K1 m RNA expression was more than two-fold higher than in normal tissue. Consistent with previous reports, LPAR2 m RNA expression in 20 of 27 colorectal cancer tissue samples was higher compared to normal tissue samples. Expression profiles of all three major S1 P receptors, S1PR1, S1PR2, and S1PR3, varied without any trend, with no significant difference in expression between cancer and normal tissues. A highly significant positive correlation was found between Sph K1 and LPAR2 expression [Pearson’s correlation coefficient(r) = 0.784 and P < 0.01]. The m RNA levels of Sph K1 and LPAR2 did not correlate with TNM stage.CONCLUSION: Our findings suggest that S1 P andLPA may play important roles in the development ofcolorectal cancer via the upregulation of Sph K1 andLPAR2, both of which could serve as new therapeutictargets in the treatment of colorectal cancer. AIM: To examine the expression of Sph K1, an oncogenic kinase that produces sphingosine 1-phosphate (S1P), and its correlation with the expression of LPAR2, a major lysophosphatidic acid (LPA) receptor overexpressed in various cancers, in human colorectal cancer. METHODS: Real-time reverse-transcription polymerase chain reaction was used to measure the m RNA expression of Sph K1, LPAR2, and the three major S1 P receptors in 27 colorectal cancer samples and corresponding normal tissue samples. We also examined the correlation between the Sph K1 m RNA expression was more than two-fold Consistent with previous reports, LPAR2 m RNA expression in 20 of 27 colorectal cancer tissue samples was higher than normal tissue samples. Expression profiles of all three major S1 P receptors, S1 PR1, S1 PR2, and S1 PR3, varied without any trend, with no significant difference in expression between cancer and normal tissues. A highly significant positive correlation found between Sph K1 and LPAR2 expression [Pearson’s correlation coefficient (r) = 0.784 and P <0.01]. The m RNA levels of Sph K1 and LPAR2 did not correlate with TNM stage. CONCLUSION: Our findings suggest that S1 P and LPA may play important roles in the development ofcolorectal cancer via the upregulation of Sph K1 and LPAR2, both of which could serve as new therapeutictargets in the treatment of colorectal cancer.