Cooperation of decay-accelerating factor and membrane cofactor protein in regulating survival of human cervical cancer cells.
BACKGROUND
Decay-accelerating factor (DAF) and membrane cofactor protein (MCP) are the key molecules involved in cell protection against autologus complement, which restricts the action of complement at critical stages of the cascade reaction. The cooperative effect of DAF and MCP on the survival of human cervical cancer cell (ME180) has not been demonstrated.


METHODS
In this study we applied, for the first time, short hairpin RNA (shRNA) to knock down the expression of the DAF and MCP with the aim of exploiting complement more effectively for tumor cell damage. Meanwhile, we investigated the cooperative effects of DAF and MCP on the viability and migration, moreover the proliferation of ME180 cell.


RESULTS
The results showed that shRNA inhibition of DAF and MCP expression enhanced complement-dependent cytolysis (CDC) up to 39% for MCP and up to 36% for DAF, and the combined inhibition of both regulators yielded further additive effects in ME180 cells. Thus, the activities of DAF and MCP, when present together, are greater than the sum of the two protein individually.


CONCLUSIONS
These data indicated that combined DAF and MCP shRNA described in this study may offer an additional alternative to improve the efficacy of antibody-and complement-based cancer immunotherapy.
Gao
Ling-Juan
LJ
Clinical Laboratory, Nanjing Maternity and Child Health Care Hospital, Nanjing, PR China. highhigh20032003@yahoo.com.cn
Guo
Shu-Yu
SY
Cai
You-Qun
YQ
Gu
Ping-Qing
PQ
Su
Ya-Juan
YJ
Gong
Hui
H
Liu
Yun
Y
Chen
Chen
C
D018958:CD55 Antigens / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002470:Cell Survival; D005260:Female; D006801:Humans; D051916:Membrane Cofactor Protein / Q000235:genetics / Q000378:metabolism*; D002583:Uterine Cervical Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology*
D018958:CD55 Antigens; D051916:Membrane Cofactor Protein