Downregulation of ADAM10 expression inhibits metastasis and invasiveness of human hepatocellular carcinoma HepG2 cells

Impact of ADAM10 gene polymorphisms on hepatocellular carcinoma development and clinical characteristics

A disintegrin and metalloprotease (ADAM) family proteins are type-I transmembrane glycoproteins with multiple functions in cell adhesion, migration, proteolysis and signaling. ADAM10 is a member of the ADAM family reportedly involved in cancer progression and has been shown to be overexpressed in hepatocellular carcinoma (HCC) tissues and significantly associated with tumor progression and shortened survival. This study investigated ADAM10's single nucleotide polymorphisms (SNPs) and their association to HCC development and regulation. Real-time polymerase chain reaction was used to analyze five SNPs of ADAM10 in 333 patients with HCC and 1196 controls without cancer. The results indicated that of the 333 patients with HCC, those who carried ADAM10 rs514049 (AC + CC) variants had a higher risk of developing lymph node metastasis (odds ratio [OR] = 5.087, p = 0.027), and those who carried ADAM10 rs653765 (GA + AA) variants had a higher risk of developing distant metastasis (OR = 3.346, p = 0.020) and higher levels of α-fetoprotein. In conclusion, our study demonstrated that the SNPs of ADAM10 are involved in HCC progression. ADAM10 SNPs may be used as therapeutic targets to evaluate poor prognoses for HCC.

miR-365 targets ADAM10 and suppresses the cell growth and metastasis of hepatocellular carcinoma

Expression of miR-365 has been reported to be downregulated in hepatocellular carcinoma (HCC). However, the biological function and underlying mechanism of miR-365 in HCC growth and metastasis remain unclear. The aim of the present study was to explore the role of miR-365 in HCC progression. We found that miR-365 expression was downregulated in HCC tissues and cell lines. Further results showed that low expression of miR-365 was significantly associated with tumor-node-metastasis (TNM) stage and lymph node metastasis. Functional assays revealed that overexpression of miR-365 significantly inhibited cell proliferation, colony formation, migration and invasion of HCC cells in vitro, and suppressed tumor growth in vivo. Mechanistic investigations demonstrated that ADAM10 (a disintegrin and metalloproteinase 10) is a target of miR-365 in HCC. In addition, knockdown of ADAM10 in HepG2 cells significantly inhibited cell proliferation, colony formation, migration and invasion, which mimicked the suppressive effects induced by miR-365 overexpression. Restoration of ADAM10 expression partially reversed the suppressive effects mediated by miR-365 overexpression. Taken together, these results indicate that miR-365 functions as a tumor-suppressor in HCC through targeting ADAM10, and may serve as a promising candidate for therapeutic applications in HCC treatment.

Clinical significance of ADAM10 expression in laryngeal carcinoma

Recent findings suggest that upregulated a disintegrin and metalloproteinase (ADAM)10 expression participates in the progression of multiple types of cancer. However, the expression pattern and clinicopathological significance of ADAM10, and its potential prognostic role in laryngeal carcinoma remains to be explored. The present study firstly determined the significantly elevated expression status of ADAM10 protein and messenger RNA in laryngeal carcinoma tissues compared with that in adjacent non-tumor tissues by western blotting and reverse transcription-quantitative polymerase chain reaction analysis. Next, the expression of ADAM10 and the proliferation marker Ki-67 was examined in 78 laryngeal carcinoma and 35 adjacent non-tumor specimens using immunohistochemistry. Overexpressed ADAM10 in laryngeal carcinoma was detected, which correlated with T classification (P<0.01), clinical stage (P<0.01), pathology (P=0.034) and Ki-67 expression (P<0.01). Furthermore, the expression of ADAM10 was positively correlated with the expression of Ki-67 (R²=0.22; P<0.01). The Kaplan-Meier method revealed that the group with overexpressed ADAM10 exhibited shorter overall survival time compared with those with low ADAM10 expression. Our findings indicated that ADAM10 serves a notable role in the progression and prognosis of laryngeal carcinoma.

ADAM10 mediates the cell invasion and metastasis of human esophageal squamous cell carcinoma via regulation of E-cadherin activity

A disintegrin and metalloprotease 10 (ADAM10) is involved in the tumorigenesis, invasion and metastasis of several types of solid tumors. However, the potential role of ADAM10 in human esophageal squamous cell carcinoma (ESCC) is not yet well understood. The present study showed that ADAM10 was overexpressed in human ESCC tissues in vivo, and positively associated with depth of tumor invasion, lymph node metastasis and TNM stage, contributing to tumor carcinogenesis, invasion and metastasis. Additionally, ADAM10 was overexpressed in 3 types of ESCC cell lines in vitro, as compared to that in normal esophageal epithelial cells (NEECs); and moreover, ESCC cells with high ADAM10 expression obtained enhanced invasion and migration ability. Subsequently, ADAM10 silencing by small interfering (si) RNA in ESCC cell line, EC-1, reduced cell invasion, migration and proliferation in vitro. Finally, ADAM10 negatively regulated E-cadherin in ESCC in vivo and in vitro. In conclusion, active ADAM10 promotes the carcinogenesis, invasion, metastasis and proliferation of ESCC and controls invasion and metastasis at least in part through the shedding of E-cadherin activity, which makes it a potential biomarker and a useful therapeutic target for ESCC.

Effects of ADAM10 upregulation on progression, migration, and prognosis of nasopharyngeal carcinoma

A disintegrin and metalloprotease 10 (ADAM10) is a typical member of the ADAMs family, which has been reported to be upregulated in various types of cancers and contribute to cancer progression and metastasis. However, little is known about the role of ADAM10 in nasopharyngeal carcinoma (NPC). The purpose of this study is to explore ADAM10 expression status and its biological functions in NPC. We first examined the expression of ADAM10 in NPC tissues and cell lines by immunohistochemistry, Western blotting, PCR, and immunofluorescence analysis. We observed that ADAM10 was significantly elevated in NPC and its expression level was correlated with T classification (P = 0.044), distant metastasis (P = 0.016), TNM clinical stage (P = 0.013), and proliferation marker Ki‐67 expression (P = 0.001). Patients with NPC with high expression of ADAM10 had shorter overall survival rates. In addition, knockdown of ADAM10 by RNAi was found to inhibit the CNE‐2 cell proliferation and migration. Our findings hinted that overexpression of ADAM10 promotes the progression and migration of NPC, which makes it a potential therapeutic target for the treatment of tumor metastases in NPC.

B7-H3 promotes aggression and invasion of hepatocellular carcinoma by targeting epithelial-to-mesenchymal transition via JAK2/STAT3/Slug signaling pathway

BACKGROUND

B7-homologue 3 (B7-H3), a recently identified immunoregulatory protein, has been shown to be overexpressed in human hepatocellular carcinoma (HCC). However, whether the dynamic expression pattern of B7-H3 contributes to early invasion of HCC is largely unknown. In addition, the biological roles of B7-H3 in HCC are still unclear. Herein, we are going to examine B7-H3 expression profile and its clinicopathological significance in primary and metastatic HCC, and further determine whether B7-H3 knockdown simulates different pathological states of HCC progression and metastasis.

METHODS

Using immunohistochemistry, B7-H3 expression was studied on 116 HCC containing primary and metastatic HCCs. Survival curves and log-rank tests were used to test the association of B7-H3 expression with survival. HCC cells with B7-H3 depletion were established by RNA interference to investigate the effect of B7-H3 on cell proliferation, apoptosis, migration and invasion in vitro.

RESULTS

Statistical analysis of clinical cases revealed that B7-H3 high expression group had inclinations towards late TNM stage, the presence of vascular invasion, lymph metastasis, and the formation of microsatellite tumors. Increased intensity of tumor B7-H3 staining was detected more significantly in metastatic HCC tumors. Consistently in experiments performed in vitro, B7-H3 was able to stimulate the wound healing, metastasis and invasion of hepatoma cells by targeting epithelial-to-mesenchymal transition (EMT) via JAK2/Stat3/Slug signaling pathway, while no obvious influence on cell growth and apoptosis.

CONCLUSION

B7-H3 in the regulation of the metastatic capacity of HCC cells makes itself a promising therapeutic target for anti-metastasis therapy.

Synergistic effects of co-expression plasmid‑based ADAM10-specific siRNA and GRIM-19 on hepatocellular carcinoma in vitro and in vivo

A disintegrin and metalloproteinase 10 (ADAM10) has been demonstrated to correlate with hepatocellular carcinoma (HCC) grade and clinical outcome and its potential as a target for HCC therapy has been established. Gene associated with retinoid-interferon-induced mortality 19 (GRIM-19), a signal transducer and activator of transcription 3 (Stat3)-inhibitory protein, was identified as a potential tumor suppressor associated with growth inhibition and cell apoptosis. In the present study, we investigated whether a combined treatment with ADAM10-specific siRNA and GRIM19 gene could have an enhanced anticancer effectiveness on HCC in vitro and in vivo. We developed a dual expression plasmid that co-expressed ADAM10-specific siRNA and GRIM19, to evaluate its effects on HCC growth. Our results showed that simultaneous expression of ADAM10-specific siRNA and GRIM19 (pSi-ADAM10-GRIM19) in HepG2 cancer cells significantly inhibited the proliferation, migration and invasion, and induced cell apoptosis in vitro, and it also suppressed tumor growth in a nude mouse model when compared to the controls, either ADAM10-specific siRNA or GRIM-19 alone. In summary, our data demonstrated that a combined strategy of co-expressed ADAM10-specific siRNA and GRIM19 synergistically and more effectively suppressed HCC tumor growth, and has therapeutic potential for the treatment of HCC.

Knockout of ADAM10 enhances sorafenib antitumor activity of hepatocellular carcinoma in vitro and in vivo

Sorafenib (SOR), a vascular endothelial growth factor receptor (VEGFR) inhibitor, is in wide clinical use for the treatment and prevention of liver cancer. However, extended SOR administration for hepatocellular carcinoma (HCC) induces drug resistance thereby limiting its efficacy and highlighting the need for improved therapeutic strategies. It has previously been demonstrated that knockout of a disintegrin and metalloproteinase 10 (ADAM10) via siRNA induced cancer apoptosis and decreased chemotherapy drug resistance. However, whether knockout of ADAM10 is able to decrease SOR resistance remains to be determined. Therefore, in the present study, the effect of siRNA-ADAM10 in combination with SOR was analyzed in HCC cell lines (HepG2) by inhibiting tumor growth and simultaneously reducing doses of SOR. Cell proliferation, apoptosis, migration, invasion and involvement in receptor signaling were determined after siRNA-ADAM10 was applied in combination with SOR treatment. Tumor growth ability in nude mice was also detected. The results showed that siRNA-ADAM10 in combination with SOR treatment in HCC cancer cells significantly suppressed proliferation, migration and invasion, and induced tumor apoptosis in vitro, and suppressed tumor growth in vivo. In addition, the results showed that knockout of ADAM10 by siRNA inhibited the constitutive phosphorylation of PI3K and AKT, which may contribute to the reduction of SOR resistance. Collectively, our experimental results indicate that knockout of ADAM10 by siRNA increased the SOR antitumor activity of liver cancer in vitro and in vivo, and that this additive combination is a promising drug candidate for treatment of HCC.