[Effect of recombinant VEGF-C secreted from eukaryotic cells on proliferation and chemotherapy-induced apoptosis of leukemic cells].
OBJECTIVE
Vascular endothelial growth factor-C/vascular endothelial growth factor receptor-2, -3 (VEGF-C/VEGFR-2,3) signaling pathway can induce angiogenesis/lymphangiogenesis, and promote invasion and metastasis of solid tumors. Recent studies showed that VEGF-C and its receptors also expressed on hematological tumor cells, but their effects on leukemic cells are unclear. This study was to explore the effects of recombinant VEGF-C secreted from VEGF-C cDNA-transfected CHO (CHO/VEGF-C) cells on proliferation and chemotherapy-induced apoptosis of leukemic cells.


METHODS
The effect of recombinant VEGF-C (in the supernatants of CHO/VEGF-C cells) on angiogenesis was observed using the chicken chorioallantoic membrane model. The expression of VEGFR-2 and VEGFR-3 on leukemic cell lines TF-1, K562, HEL, NB4, HL-60, MR2, U937,SHI-1, and RPMI8226 was detected by reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry (FCM). The effect of VEGF-C on the proliferation of NB4 and K562 cells was assessed by MTT assay; its effect on the apoptosis of NB4 cells, which were treated with chemotherapeutic agents [etoposide (VP-16), daunorubicin (DNR), or arsenic trioxide (As2O3)], was investigated by FCM with Annexin V/PI double staining. The supernatant of CHO/pcDNA3.1 cells was used as control.


RESULTS
The recombinant VEGF-C induced angiogenesis in the chicken chorioallantoic membrane model. VEGFR-3 was expressed in NB4, HEL, and RPMI8226 cells; VEGFR-2 was expressed in HEL and TF-1 cells. Compared with the controls, the recombinant VEGF-C promoted the proliferation of NB4 cells (VEGFR-3(+)) (P(24h)=0.006, P(48h)=0.018), but had no effect on K562 cells (VEGFR-3(-)); it inhibited the chemotherapy-induced apoptosis of NB4 cells (P(VP-16)=0.019, P(DNR)=0.013, P(As2O3)=0.042).


CONCLUSIONS
The recombinant VEGF-C could induce angiogenesis, and may promote the proliferation and inhibit the chemotherapy-induced apoptosis of leukemic cells via VEGFR-3 signaling pathway, which might be potential target therapy for leukemia.
Ding
Kai-Yang
KY
Jiangsu Institute of Hematology, The First Affiliated Hospital, Soochow University, Suzhou, Jiangsu, P.R. China.
Bai
Xia
X
Dai
Lan
L
Dong
Ning-Zheng
NZ
Ruan
Chang-Geng
CG
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D016466:CHO Cells; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002642:Chick Embryo; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D007938:Leukemia / Q000378:metabolism* / Q000473:pathology; D042583:Lymphangiogenesis; D009389:Neovascularization, Pathologic; D011994:Recombinant Proteins / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection; D042582:Vascular Endothelial Growth Factor C / Q000378:metabolism* / Q000502:physiology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism*; D040321:Vascular Endothelial Growth Factor Receptor-3 / Q000378:metabolism*
D011994:Recombinant Proteins; D042582:Vascular Endothelial Growth Factor C; D040301:Vascular Endothelial Growth Factor Receptor-2; D040321:Vascular Endothelial Growth Factor Receptor-3