The Effects Of A-type Potassium Channels On The Proliferation Of Human Tongue Squamous Cell Carcinoma Tca8113 Cells

Oral Cancer（OC）is one of systemic cancers with high incidence,which has threatened and damaged in people’s physical and mental health.Its cure rate is lower,and the cure rate of terminal oral cancer not only is reducing but also has accompanied by higher recurrence rate at the same time.The oral squamous cell carcinomas（OSCC）is the highest incidence in OC,and the main way of treating OSCC is a multidisciplinary team（MDT）at present.To a certain extent,MDT has improved the availability of treatment,in order to achieve clinical precision medicine,but we are the establishment of new drugs and find innovative ways to improve specific curative effects.With microcosmic in-depth understanding of cancer,some oncologists focus on ion channels.More and more convincing evidences show that some potassium channels’change will be supposed to give rise to change the cell proliferation and apoptosis.These existing funds that 4-aminopyridine（4-AP）can block the A-type potassium channels in the cell membrane.After channel activitys alter.Those changes impact some cancer cell proliferations.Objective:From A-type channel,we explore the response to the A-type potassium channels（Kv,K_A）on the cell membrane is blocked by 4-AP in tongues,and discuss A-type channel effects cutaneous carcinoma of the strains（Tca8113）cells.Methods:Culticating Tca8113 cells in vitro,we use 3-（4,5-dimethyl thiazole-2）-2,5-diphenyl four azole nitrogen bromine salt（3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl-2-H-tetrazolium bromide）colorimetric method（MTT method）,respectively in 0 houre,24 houre,48 houre,72 houre,96 houre,120houre,144 houre of each point,to detect concentrations of 4-AP with 8 mM,4mM,2 mM,1 mM,0.5 mM and 0.1 mM each group,control group and blank group in the optical density（OD）values.Using whole cell patch clamp technique,we record in the I_to with the control group（no.4-AP）and experimental group（final concentration of 4-AP in 2 mM）on the Tca8113membrane A-type K⁺current value.Application SPSS17.0 software with repetitive Measure analysis of variance（Reapeated Measure）,LSD method and group t test analysis results.When the probability is lower than 0.05（P<0.05）,the difference has statistical significance.Results:On the macro,detected by the MTT method founds:（1）in the final concentration 1 mM,0.5 mM,0.1 mM4-AP influence cells after 24 hours.We find no observable changes in these cells.However,cells’morphology and numbers reduce relative.The final concentration is 8 mM,4 mM,2 mM 4-AP to impact the same time,cells are prior to circular and spherical.（2）in the 144 hours of experimental observation,the blank group OD value of 0.075,basic remain unchanged;In the control group OD value stable and rose to 1.078 from 0.311;0.1 mM OD value of the experimental group from 0.324 to 1.025;0.5 mM OD value of the experimental group from 0.314 to 0.96;1 mM OD value of the experimental group from0.313 to 0.956;2 mM OD value of the experimental group from 0.325 to 0.996;4 mM OD value of the experimental group from 0.300 to 0.818;8 mM OD value of the experimental group from 0.315 to 0.073.Using repetitive measure analysis of variance,we found that the interaction between time and concentration（P<0.001）.When analyzed separately concentration effect and time effect（P<0.001）,difference was statistically significant.The drug concentration and cell proliferation inhibition are time dependent.Time effects are considered,the cell proliferation increases by time（P<0.001）.（3）After 72hours with 8 mM 4-AP affect cells,the inhibition rate about 90%on average,4mM 4-AP affect cells,the inhibition rate close to 50%,and the rest of the groups’inhibition rates have lower than 20%.LSD method,using 8,4,2 mM 4-AP impact cells,knows the effect of inhibition in cell proliferation has the difference between the other groups（P<0.05）.72 hours later,the inhibition rates basically go to stable and falling.On microscopic,electrophysiology results found these:（1）the final concentration of 4-AP with 2 mM under the preliminary experiment,the peak of A-type K⁺current(transient outward potassium current,I_A,I_to)is decreased to 124.81±5.24 pA from 267.04±13.84pA.The group t test analysis shows that each group of data of P values is less than or equal to 0.001.The difference was statistically significant.That 4-AP block of A-type K⁺channel is changing the process of I_to on the cell membranes.（2）with the altered test voltage（TP）from-60 mV to 70 mV,the I_to of without 4-AP group is from 61.56±9.57 pA to 267.04±13.84 pA,and the I_to of with 4-AP group is from 49.50±9.85 pA to 124.81±5.24 pA,P<0.005,the difference was statistically significant,to illustrate the voltage dependence of the proposed channel.（3）the cell membrane capacitance in the experiment of the average is about 0.986±0.583 uF/cm²,and different individuals of similar cell membrane capacitance is basically comparable.Conclusion:（1）Through the experiment,we see that A-type K⁺current exists on the OSCC cell surface,and I_to has the voltage dependence on the cell membrane.The same kind of cell membrane capacitance is basically analogous.（2）In the final concentration of 8mM experiments,the final concentration of unity,the effect of 4-AP inhibition of cell proliferation have time dependence;within 144 hours,at the same time point,the different concentrations of 4-AP inhibited the cell proliferation on the effect of concentration dependence.（3）After 72 hours under the drugs,the cell proliferation may be limited to nutrition,drug concentration change or cell resistance increase.And then,the trend of the cell in proliferous speed tends to be weakened slightly or stably.（4）A-type K⁺channel block will affect Tca8113 cells proliferation.The channel may participate in the process of Tca8113 cells proliferation.