High expression of patched homolog-1 messenger RNA and glioma-associated oncogene-1 messenger RNA of sonic hedgehog signaling pathway indicates a risk of postresection recurrence of hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) has a high recurrence rate after resection. Abnormal activation of the sonic hedgehog (SHH) signaling pathway contributing to the carcinogenesis of some organs had been reported. We hypothesize that activation of SHH pathway contributes to the recurrence of HCC after surgical resection. METHODS: In a prospective study, from January 2006 to June 2010, a total of 50 consecutive patients with HCC after curative resection were enrolled. The ratio of the expression of messenger RNA (mRNA) of SHH, patched homolog-1 (PTCH-1) and glioma-associated oncogene-1 (GLI-1) between HCC tissues and the paired noncancerous liver tissues were measured. Both the clinicopathologic characteristics and these ratios were compared between those with recurrence and those without recurrence. They were also compared between those with and without survival. RESULTS: There was a statistically significant correlation among the ratios of PTCH-1 mRNA and serum AFP level (p = 0.045), tumor size (p = 0.001), vascular permeation (p = 0.043) and tumor, node, metastasis staging system (TNM) stage (p = 0.003). A borderline significant correlation was found among ratios of GLI-1 mRNA and tumor size (p = 0.062) and TNM stage (p = 0.051). There was no such significant correlation between SHH mRNA and any parameter. Both the ratios of PTCH-1 mRNA and GLI-1 mRNA significantly adversely affected recurrence (p = 0.003 and 0.005, respectively) and survival (p < 0.001 and <0.001, respectively). CONCLUSIONS: Expression of PTCH-1 mRNA and GLI-1 mRNA in HCC tissues is a potential biomarker to predict postresection disease recurrence.

Liver epithelial cells inhibit proliferation and invasiveness of hepatoma cells.

Hepatocellular carcinoma (HCC) is a worldwide malignancy with poor prognosis. Liver progenitors or stem cells could be a potential therapy for HCC treatment since they migrate toward tumors. Rat liver epithelial (RLE) cells have both progenitor and stem cell-like properties. Therefore, our study elucidated the therapeutic effect of RLE cells in rat hepatoma cells. RLE cells were isolated from 10-day old rats and characterized for stem cell marker expression. RLE cells and rat hepatoma cells (H4-IIE-C3 cells) were co-cultured and divided into four groups with different ratios of RLE and hepatoma cells. Group A had only rat hepatoma cells as a control group. The ratios of rat hepatoma and RLE cells in group B, C and D were 5:1, 1:1 and 1:5, respectively. Effective inhibition of cell proliferation and migration was found in group D when compared to group A. There was a significant decrease in Bcl2 expression and increase in late apoptosis of rat hepatoma cells when adding more RLE cells. RLE cells reduced cell proliferation and migration of rat hepatoma cells. These results suggested that RLE cells could be used as a potential cell therapy.

Sonic hedgehog pathway inhibitor mitigates mouse hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a leading cause of death in Asian countries. Sonic hedgehog (Shh) pathway plays a role in hepatocarcinogenesis. We investigated the treatment effect of mouse HCC with Shh inhibitor GDC-0449. METHODS: Mouse hepatoma ML-1 cells were implanted in B6 mice. Fifteen days later, GDC-0449 (vismodegib), antagonist of smoothened, was used to treat HCC-bearing mice. The tumor size and liver histopathological features were analyzed, as well as gene expression in Shh pathways. RESULTS: GDC-0449 treatment effectively reduced tumor size and cell infiltration of the HCC in mice. Gene expression of Shh pathway molecules was altered, including upregulated Shh expression and downregulated smoothened expression in tumor fractions after GDC-0449 treatment. CONCLUSION: GDC-0449 could effectively mitigate HCC growth in vivo.

Activation of the sonic hedgehog signaling pathway occurs in the CD133 positive cells of mouse liver cancer Hepa 1-6 cells.

BACKGROUND: The important role of cancer stem cells in carcinogenesis has been emphasized in research. CD133+ cells have been mentioned as liver cancer stem cells in hepatocellular carcinoma (HCC). Some researchers have proposed that the sonic hedgehog (Shh) pathway contributes to hepatocarcinogenesis and that the pathway activation occurs mainly in cancer stem cells. We investigated whether the activation of the Shh pathway occurs in CD133+ cells from liver cancer. MATERIALS AND METHODS: We used magnetic sorting to isolate CD133+ cells from mouse cancer Hepa 1-6 cells. To examine the clonogenicity, cell culture and soft agar colony formation assay were performed between CD133+ and CD133- cells. To study the activation of the Shh pathway, we examined the mRNA expressions of Shh, patched homolog 1 (Ptch-1), glioma-associated oncogene homolog 1 (Gli-1), and smoothened homolog (Smoh) by real-time polymerase chain reaction of both CD133+ and CD133- cells. RESULTS: The number (mean ± standard deviation) of colonies of CD133+ cells and CD133- cells was 1,031.0 ± 104.7 and 119.7 ± 17.6 respectively. This difference was statistically significant (P < 0.001). Their clonogenicity was 13.7% ± 1.4% and 1.6% ± 0.2% respectively with a statistically significant difference found (P < 0.001). CD133+ cells and CD133- cells were found to have statistically significant differences in Shh mRNA and Smoh mRNA (P = 0.005 and P = 0.043 respectively). CONCLUSION: CD133+ Hepa 1-6 cells have a significantly higher colony proliferation and clonogenicity. The Shh pathway is activated in these cells that harbor stem cell features, with an underexpression of Shh mRNA and an overexpression of Smoh mRNA. Blockade of the Shh signaling pathway may be a potential therapeutic strategy for hepatocarcinogenesis.

High expression of Sonic Hedgehog signaling pathway genes indicates a risk of recurrence of breast carcinoma.

BACKGROUND: Abnormal activation of the Sonic Hedgehog (SHH) signaling pathway contributing to carcinogenesis of some organs has been reported in the literature. We hypothesize that activation of the SHH pathway contributes to the recurrence of breast carcinoma. METHODS: Fifty consecutive patients with invasive breast carcinoma following curative resection were enrolled in this prospective study. The ratios of messenger RNA (mRNA) expression for Sonic Hedgehog (SHH), patched homolog-1 (PTCH-1), glioma-associated oncogene-1 (GLI-1), and smoothened (SMOH) were measured between breast carcinoma tissue and paired noncancerous breast tissue. These ratios were compared with their clinicopathologic characteristics. These factors and the mRNA ratios were compared between patients with recurrence and those without recurrence. RESULTS: The size of the invasive cancer correlated significantly with the ratio of SHH mRNA (P=0.001), that of PTCH-1 mRNA (P=0.005), and that of SMOH mRNA (P=0.021). Lymph node involvement correlated significantly with the ratio of SMOH mRNA (P=0.041). The correlation between Her-2 neu and the ratio of GLI-1 mRNA was statistically significant (P=0.012). Each ratio of mRNA of SHH, PTCH-1, GLI-1, and SMOH correlated significantly with cancer recurrence (P<0.001 for each). CONCLUSION: We suggest that high expression of SHH mRNA, PTCH-1 mRNA, GLI-1 mRNA, and SMOH mRNA in breast cancer tissue correlates with invasiveness and is a potential biomarker to predict postoperative recurrence.

Blockade of the sonic hedgehog pathway effectively inhibits the growth of hepatoma in mice: An in vivo study.

Hepatocellular carcinoma (HCC), a worldwide malignancy, is prevalent in Asian countries. For individuals with unresectable HCC, the effect of chemotherapy or the present target therapy is limited. There is an urgent need to find innovative new therapies. It is believed that sonic hedgehog (Shh) pathway activation may be essential for hepatocarcinogenesis. In the present study, we conducted an in vivo animal study using an Shh pathway inhibitor to elucidate the effect of treatment upon mice with HCC. Eighty C57BL/6 mice were divided into 4 groups (groups A, B, C and D, with group A serving as a control; n=20 for each). We injected mouse hepatoma Mistheton Lectin-1 cells (5×10(6) cells/20 µl) into the left liver of each mouse in groups B, C and D. In the second week, we analyzed each mouse to assess the tumor growth status. Following the tumor injection, group B did not receive any additional intraperitoneal (i.p.) injection, group C received cyclopamine 10 mg/kg/day i.p. and group D received cyclopamine 30 mg/kg/day i.p. every day for 10 days. After an interval of 4 weeks, harvesting and analysis of the liver was performed for each mouse. Tumor size measurement and real-time PCR of Shh pathway factors (Shh, Ptch-1, Gli-1 and Smoh) for livers of group A and tumors of group B, C and D were undertaken. The decrease in the tumor size of group D was found to be statistically significant (P= 0.047) when compared with groups B or C. The decrease of Shh mRNA of both groups C and D had borderline significance when compared with group B. However, Gli-1 mRNA of group D has statistically significant difference (P=0.044) when compared with group A, B or C. Inhibition of the Shh pathway significantly decreases the size and Gli-1 mRNA expression of the tumor. The Shh pathway may be an effective treatment target for HCC in the future.