Hint1 suppresses migration and invasion of hepatocellular carcinoma cells in vitro by modulating girdin activity.
Histidine triad nucleotide-binding protein 1 (Hint1) is a haploinsufficient tumor suppressor gene. Its role in cancer cell migration has not been previously speculated. In the current study, we examined the expression of Hint1 in metastatic and non-metastatic lymph nodes of hepatocellular carcinoma (HCC) patients and further elucidated the effect of Hint1 expression on girdin expression and phosphorylation of AKT and ERK1/2 and on the migration of HCC cells in vitro. Expression of Hint1 and girdin in primary HCC tissues and metastatic and non-metastatic lymph nodes was determined by RT-PCR assays. HepG2 cells were transfected with plasmid vectors overexpressing Hint1 or small interfering RNA (siRNA) targeting Hint1, girdin, Hint1 plus girdin, or the scrambled RNA. Migration and invasion of HCC cells were examined by wound and Transwell assays. Protein expression was detected by immunofluorescence and immunoblotting assays. RT-PCR assays revealed that the messenger RNA (mRNA) transcript levels of Hint1 were markedly lower than those of primary HCC tissues and non-metastatic lymph nodes (P < 0.01). By contrast, the mRNA transcript levels of girdin were significantly higher than non-metastatic lymph nodes (P < 0.05). Furthermore, siRNA knockdown of HINT1 resulted in a significant increase in the mRNA transcript levels of girdin in HepG2 cells (P < 0.05). Wound assays and Transwell assays showed that Hint1 knockdown by siRNA significantly enhanced the migration and invasion of HepG2 cells compared to HepG2 cells transfected with scrambled siRNA. Hint1 knockdown also led to significantly increased phosphorylation of girdin and AKT in HepG2 cells (P < 0.05), which, however, was effectively aborted by girdin knockdown by siRNA (P < 0.05). Hint1 is downregulated in metastatic lymph nodes and is implicated in migration and invasion of HCC cells in vitro by modulating girdin and AKT expression and phosphorylation. The Hint1-girdin-AKT signaling axis should be further dissected for its role in HCC migration and invasion and may be therapeutically targeted to suppress tumor growth and metastasis.
Department of Gastroenterological Surgery, the Second Affiliated Hospital of Kunming Medical University, Kunming City, Yunnan Province, People's Republic of China.
Xue-Song
XS
Wu
Department of Hepatobiliary Surgery, the Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People's Republic of China.|Mental Health Center of Kunming Medical University, Kunming City, Yunnan Province, People's Republic of China.
Tian-Hao
TH
Bao
Department of Hepatobiliary Surgery, the Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People's Republic of China.
Yang
Y
Ke
Department of General Surgery, the Second People's Hospital of Qujing City, Qujing City, Yunnan Province, People's Republic of China.
De-Yun
DY
Sun
Department of Hepatobiliary Surgery, the Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People's Republic of China.
Zhi-Tian
ZT
Shi
Department of Gastroenterological Surgery, the Second Affiliated Hospital of Kunming Medical University, Kunming City, Yunnan Province, People's Republic of China.
Hao-Ran
HR
Tang
Department of Hepatobiliary Surgery, the Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People's Republic of China. wl_phd@126.com.
Lin
L
Wang
D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism / Q000556:secondary*; D002465:Cell Movement; D049109:Cell Proliferation; D005260:Female; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate; D014407:Tumor Cells, Cultured; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism*
D014408:Biomarkers, Tumor; C502451:CCDC88A protein, human; C063306:HINT1 protein, human; D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D033921:Vesicular Transport Proteins
AKT; Girdin; Hepatocellular carcinoma; Hint1; Invasion; Migration