However, pretreatment with FPR1 antagonists cyclosporin H or tBoc-MLF reduced the response of HepG2 and Hep3B cells induced by fMLF (Fig.?S4D-I). production of angiogenic factor IL-8 by human gliobstoma.7,17 FPR1 in glioblastoma cells also interacts with agonists released by necrotic tumor cells, 7 suggesting that tumor cells may utilize FPR1 to recognize agonists produced in the tumor microenviroment for their advantage. Since hepatocarcinogenesis involves a highly orchestrated interplay of injury, chronic inflammation and neovascularization, 2 the multitude NMS-P515 of FPR1 suggests that it may also play a role in the development of hepatic cancer.5-7, Gusb 9,17 In the present study, we report that FPR1 was expressed by HCC tissues from patients and the human hepatoma cell lines. Hepatoma cells responded to the FPR1 agonist fMLF by increased motility, proliferation and enhanced IL-8 production. FPR1 small hairpin RNA (shRNA) substantially reduced the tumorigenicity of hepatoma cells in nude mice. Our study thus demonstrates a significant role of FPR1 in the carcinogenesis of human hepatoma. Results The expression of FPR1 on human hepatocellular carcinoma tissues We performed histologic and immune fluorescence staining of FPR1 in tumor tissues from HCC patients. In surgical specimens, hematoxylin-eosin (H&E)-staining revealed poorly (Fig.?1A) and moderately (Fig.?1B) differentiated HCC with a trabecular pattern. In the high-grade intratumor specimens, multiple tumors of intrahepatic metastases and portal vein invasion were observed. The cellular and nuclear pleomorphism, intracellular vacuoles, mitotic patterns, vessel formation and the necrosis in central tumor tissues were also demonstrated (Fig.?1A, upper right panels). The peritumor (Fig.?1A and B, lower right panels) liver tissue showed a chronic inflammatory infiltration in the fibrous NMS-P515 stroma, diagnosed as hepatic cirrhosis. Strong FPR1 signal was detected in grade III HCC specimens (Fig.?1A, left panels), and positive staining was enriched in intratumor area Fig.?1A, upper left panels). In contrast, the lesser aggressive grade II hepatoma specimens showed intermediate staining intensity of FPR1 in intratumoral tissues (Fig.?1B, upper left panels) and very low FPR1 expression in peritumoral tissues (Fig.?1B, lower left panels). We then NMS-P515 examined whether FPR1 expression is selectively enhanced in hepatocellular carcinoma. Fig.?1C shows that protein NMS-P515 was detectable in human normal liver tissues adjacent to HCC. However, the levels were far lower than that in HCC tissues. Very few FPR1-positive cells were found in the adjacent normal liver tissues, demonstrating that FPR1 expression is selective in HCC and in particular in intratumor tissues. Open in a separate window Figure 1. FPR1 expression in human hepatocellular carcinoma tissues. Sections of 20 samples from grade III (A) and II (B) hepatocellular carcinoma and 10 samples of adjacent normal liver tissues (C) were stained with an antibody against FPR1 (green) and counterstained with DAPI (blue). Representative intratumor (upper panels) and peritumor (lower panels) immunofluorescence staining (left panels) and corresponding H&E staining (right panels) are shown. Bar = 100?m. (D), quantitative PCR analysis showing the level of FPR1 gene in intratumor or peritumor tissues of grade III and II hepatocellular carcinoma and adjacent normal liver tissues. The data was shown as the mean-fold changes of FPR1 expression levels ( NMS-P515 SEM) after intra-sample normalization to the levels of GAPDH. adjacent normal liver tissues in values. We next measured FPR1 RNA in HCC tissues and found FPR1 mRNA was higher in grade III than in grade II carcinoma specimens. The highest mRNA expression was found in the poorly-differentiated intratumor samples (Fig.?1D and Fig.?S1A and B),.
However, pretreatment with FPR1 antagonists cyclosporin H or tBoc-MLF reduced the response of HepG2 and Hep3B cells induced by fMLF (Fig