We also examined the expression of human CYPJ in fetal 1393124-08-7 livers and identified that CYPJ experienced higher expression in fetal livers than in typical adult livers (Fig 1B). Independently, we examined the expression of CYPJ in 40 pairs of HCC/adjacent non-cancerous tissues by semi-quantitative RT-PCR, and the results had been in arrangement with that from the Northern blot analyses, in which human CYPJ was identified to be elevated in 26/40 (65%) tumor specimens (Fig 1C). The relationship of elevated CYPJ expression with medical grades of HCC was also examined (Fig 1D). CYPJ was discovered to be upregulated in twelve/22 (54.five%) HCC clients with Grade disease and in 28/34 (82.five%) HCC clients with Quality ailment (P<0.01). In addition, the level of CYPJ in another 15 pairs of HCC/adjacent non-cancerous tissues samples was investigated by Western blot. Result showed that in 9/15 (60%) HCC samples an elevated CYPJ expression was observed (Fig 1E), which was consistent with the Northern result. In 3/15 (20%) samples the expression level of CYPJ remained unchanged while in 3/15 (20%) samples decreased. These data suggested that CYPJ was upregulated in HCC tissues which might play a role in the progression of the malignancy.Fig 1. Expression pattern of CYPJ gene and its upregulation in HCC. (A) Northern blot analysis of CYPJ in 16 main human tissues. (B) Northern blot analysis of CYPJ expression in 16 paired HCC/adjacent liver tissues and two fetal liver tissues. (C) Semi-quantitative RT-PCR analysis of CYPJ expression in 40 paired HCC/adjacent tissues. (D) Stage plots of deregulated CYPJ levels in 56 paired HCC/adjacent liver tissues. CYPJ levels were determined by Northern blot/RT-PCR. -actin was used as internal control, and DR values were calculated. (E) Western blot of CYPJ expression in 15 paired HCC/adjacent normal tissues using antiPPIL3 antibody. -actin was used as internal control. Fold change of CYPJ expression in tumor = (T/TC)/(N/ NC). T: tumor tissue sample. N: adjacent normal tissue sample. TC: tumor sample control. NC: normal tissue sample control.The deduced amino acid sequence1727499 of CYPJ showed 50% similarity with human CYPA and 72% similarity with CYP-10 of C. elegant. These characteristics indicated that CYPJ may be a novel peptidyl-prolyl cis/ trans-isomerase. To characterize CYPJ biochemically, we expressed and purified recombinant CYPJ in E. coli (Fig 2A). The relative molecular weight of the purified protein was 19379.34 Da as determined by LC/MS. The enzymatic activity of human CYPJ was determined. In the chymotrypsin-coupled assay with different concentration of the peptide substrate, the recombinant human CYPJ appeared to follow Michaelis-Menten kinetics (Fig 2B). The value of kcat and KM were estimated to be 34.2.3 s-1 and 81452 M by a double reciprocal Lineweaver-Burke plot of 1/v against 1/ [S], yielding a kcat/KM value of (4.20.29)04 M-1S-1.