[Effect of HIF-1α   and its mechanism on invasion and metastasis of esophageal carcinoma Eca109 cells in vitro and in vivo].
OBJECTIVE
To investigate the effects of HIF-1α by RNAi on invasion and metastasis of esophageal carcinoma Eca109 cells in vitro and in vivo,  in order to explore its probable mechanism.


METHODS
CoCl(2); was used to mimic tumor hypoxic microenvironment. mRNA and protein levels of HIF-1α,  E-cadherin and MMP-2 under hypoxia were detected by RT-PCR and immunohistochemistry. The effects of silencing HIF-1α by RNAi on HIF-1α,  E-cadherin and MMP-2 mRNA were detected by RT-PCR. The effect of RNAi on invasion and metastasis were tested by cell scratch assay and transwell chambers. The Eca109-implanted nude mouse model was established,  and the effects of HIF-1αon tumor growth and lymphoid node metastasis were observed. The expressions of HIF-1α,  E-cadherin and MMP-2 in transplanted tumors were detected by Western blot,  and the effects of HIF-1α on tumor growth,  invasion and metastasis in vitro and in vivo were analyzed.


RESULTS
Hypoxia up-regulated HIF-1α protein,  mRNA and protein levels of E-cadherin down-regulated,  and MMP-2 up-regulated,  while had no effect on HIF-1α mRNA . RNAi could silencing HIF-1α effectively,  and inhibited E-cadherin or MMP-2 decreased or increased,  respectively. The migration and the number of invading cells decreased (P<0.05) after silencing HIF-1α by RNAi. The tumor volume was much smaller,  lymph node metastasis rate lower as well in vivo (P<0.05).


CONCLUSIONS
Via its effects on E-cadherin and MMP-2,  HIF-1α regulate the growth,  invasion and metastasis of Eca109 cells in vitro and in vivo.
Department of Radiotherapy,  Fourth Hospital of Hebei Medical University,  Shijiazhuang 050011, China.
Shao-wu
SW
Jing
Ya-di
YD
Wang
Ming-min
MM
Zheng
Guo-gui
GG
Sun
Qing
Q
Liu
Yun-jie
YJ
Cheng
Cong-rong
CR
Yang
D000818:Animals; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D015687:Cell Hypoxia / Q000235:genetics; D045744:Cell Line, Tumor; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics* / Q000378:metabolism*; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D009361:Neoplasm Invasiveness / Q000235:genetics; D009362:Neoplasm Metastasis / Q000235:genetics; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D014183:Transplantation, Heterologous
D015820:Cadherins; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger; D020778:Matrix Metalloproteinase 2