Objective      To investigate the malignant biological behavior of HeLa cells treated with sublethal dosage of pulse electric fields (PEFs)

and to explore the possibilities of the proliferation

metastasis and invasion of residual malignant cells promoted by irreversible electroporation ablation.       Methods      HeLa cells were treated with sublethal dosage of PEFs (500

750 and 1 000 V/cm

respectively)

and normal HeLa cells were used as control. The viability of HeLa cells was detected by cell counting kit-8 (CCK8). Matrigel adhesion experiment

Transwell chamber and scratch wound assay were used to detect the adhesive ability

invasion and migration of HeLa cells after treated with the sublethal dosages of PEFs

respectively.       Results      The proliferation of HeLa cells was the same as that of the control cells at 12

24

48 and 72 h after ablation by varied sublethal dosages of PEFs. With sublethal dosage of PEFs (500

750 and 1 000 V/cm)

the rates of inhibition on HeLa cell adhesion were 9.38%

30.21% and 42.70%

respectively. From the control group to the three experimental groups

the numbers of HeLa cells invaded through the matrigel were 104.17±4.59

101.82±5.76

78.39±6.18 and 67.91±5.94

respectively

and the wound healing rates were (53.46±8.07)%

(48.75±9.13)%

(36.49±7.36)% and (30.58±5.91)%

respectively. The number of HeLa cells invaded through the matrigel in the 750 V/cm group and 1 000 V/cm group was significantly less than that in the control group (P0.05)

and the wound healing rate of the control group was significantly greater than those of the 750 V/cm group and 1 000 V/cm group. The sublethal dosage of PEFs could inhibit the adhesion

invasion and migration of HeLa cells in a dose-dependent manner.       Conclusion      Sublethal dosage of PEFs does not affect HeLa cell proliferation

but can inhibit HeLa cell invasion and metastasis in vitro. It suggests that even though irreversible electroporation can not completely ablate HeLa cells in one time in vitro

it does not promote the malignant biological behavior of residual HeLa cells in a short term.