Effects of histamine on growth and apoptosis of human melanoma cells A375

Objective: To investigate the effects of histamine on growth and apoptosis of human melanoma cells A375. Methods: The effect of histamine on growth of A375 cells in vitro was examined by MTT assay and Trypan blue exclusion assay. Cell cycle analysis, early apoptosis analysis by double staining with Annexin V-FITC and PI, and active caspase-3 analysis by staining FITC-conjugated monoclonal rabbit anti-active caspase-3 antibody were made by flow cytometer. StreptAvidin-Biotin Complex (SABC) immunocytochemical assays were adopted to detect Bax/Bcl-2 protein expressions.Results: Histamine inhibited proliferation of A375 cells in a dose- and time-dependent manner, and altered cell cycle distribution of A375 cells revealing an increase in G0/G1-phase population, a decrease in S-phase population and the inhibition of G1/S switching. Histamine induced apoptosis of A375 cells (P<0.05), elevated the cells population with detectable active caspase-3 (P<0.05), increased the number of cells forming Bax and decreased the number of cells forming Bcl-2 significantly (P<0.05). Conclusion: That histamine inhibits cell cycle progress of A375 cells is one of the possible mechanisms of proliferation arrest of A375 cells elicited by histamine. Histamine mediates apoptosis in A375 cells that may be caspase-dependent through mitochondria routine. Histamine with high concentration inhibits growth of A375 cells in vitro by interfering proliferation and inducing apoptosis of cells.

Apoptotic Effect of Cryptotanshinone on Human Melanoma A375 Cells

[Objectives] The aim was to investigate the effect of cryptotanshinone on apoptosis of human melanoma A375 cells and its related mechanism of mitochondrial pathway.[Methods]The cytotoxic effect of cryptotanshinone on apoptosis of human melanoma A375 cells was detected by MTT colorimetry.The apoptosis of melanoma A375 cells was detected with Annexin V-FITC/PI and observed by fluorescence inverted microscope.The expression of apoptosis-related proteins was detected by Western blotting.[Results]The viability of the A375 cells decreased with the increase of drug concentration.The fluorescence intensity of the cells increased with the treatment time.The expression of pro-apoptotic protein caspase-3 gradually increased,while the expression of apoptosis-inhibiting proteins p-AKT and Bcl-2 gradually reduced.[Conclusions]Cryptotanshinone induces apoptosis of human melanoma A375 cells via AKT signaling pathway,thus exerting a good cytotoxic effect on A375 cells.

Inhibitory effect of M3 receptor antagonist 4-DAMP on melanoma proliferation of A375 cell line

Objective: he effect of M3 receptor antagonist 4-DAMP (4-diphenylacetoxy-N-methylpiperidine-methiodide) on the proliferation of melanoma were explored, and the development prospect and significance of M3 receptor antagonist in the field of anti-tumor were discussed. Methods: The viability of tumor cells was detected by MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) colorimetry. The optimal concentration of 4-DAMP was screened and the effect of the drug was confirmed by EdU (5-ethynyl-2'-deoxyuridine) fluorescence staining. Adult male BALB/c nude mice were divided into control group, 5-Fu (5-Fluorouracil, 5-Fluorouracil, 20 mg/kg/d) group and 4-DAMP (2 mg/kg/d) group to establishtumor-bearing model in vivo. The tumor volume curve was calculated and plotted. Mice were killed after 21 days of continuous administration. Strip the tumor, take pictures and meatured the weighs, and calculate the inhibition rate. [1]The spleen was weighed and the spleen index was culculated. H & E staining was used to observe the pathological changes of tumor sections. The gene expression of M3R、MIA (Melanoma inhibitory activity, MIA)、SP-1 (Transcription factor Sp1, SP-1) and Lnc-SPRY4-IT1 (SPRY4 Intronic Transcript 1,Lnc-SPRY4-IT1) in A375 cell line was detected by real-time quantitative PCR (quantitative reverse-transcription polymerase chain reaction, qRT-PCR). The protein level of ERK1/2 (extracellular signal-regulated kinase 1/2,ERK1/2) was detected by Western Blot. Results: 4-DAMP could significantly inhibit the activity of A375 cell line (P < 0.01), and EdU staining demonstrated that 4-DAMP inhibited the growth of A375 cell line. The results of animal experiments showed that compared with the control group, the volume and mass of tumor in 5-Fu group and 4-DAMP group were significantly reduced (P < 0.05) and H & E staining showed that the intercellular space became larger, connective tissue increased, and tumor growth was obstructed. Compared with the control group, the tumor inhibition rate of 4-DAMP group was 72.01% (P < 0.01). There was no significant difference in body mass and spleen index. Compared with the control group, the expression of MIA, SP-1 and LncRNA-SPRY4-IT1 was decreased by 4-DAMP or si-M3R transfection. Compared with the control group, the expression of ERK1/2 was decreased by 4-DAMP or si-M3R transfection. Conclusions: These results suggest that M3 receptor antagonist 4-DAMP can inhibit the proliferation of melanoma and reduce the expression of mRNA of MIA, SP-1 and LncRNA-SPRY4-IT1 and the protein level of ERK1/2 in A375 tumor cells.

ETM study of electroporation influence on cell morphology in human malignant melanoma and human primary gingival fibroblast cells

Objective:To estimate electroporation(EP) influence on malignant and normal cells.Methods: Two cell lines including human malignant melanoma(Me-43) and normal human gingival fibroblast(HCFs) were used.EP parameters were the following:230,1000,1 730,2 300 V/cm;30 μ s by 3 impulses for every case.The viability of cells after EP was estimated by MTT assay. The ullrastructural analysis was observed by transmission electron microscope(Zeiss EM 900). Results:In the current study we observed the intracellular effect following EP on Me-43 and HGF cells.At the conditions applied,we did not observe any significant damage of mitochondrial activity in both cell lines treated by EP.Conversely,we showed that EP in some conditions can stimulate cells to proliferation.Some changes induced by EP were only visible in electron microscopy.In fibroblast cells we observed significant changes in lower parameters of EP(230 and 1 000 V/cm).After applying higher electric field intensities(2 300 V/cm) we detected many vacuoles,myelin-like bodies and swallowed endoplasmic reticulum.In melanoma cells such strong pathological modifications after EP were not observed,in comparison with control cells. The ultrastructure of both treated cell lines was changed according to the applied parameters of EP.Conclusions:We can claim that EP conditions are cell line dependent.In terms of the intracellular morphology,human fibroblasts are more sensitive to electric field as compared with melanoma cells.Optimal conditions should be determined for each cell line.Summarizing our study,we can conclude that EP is not an invasive method for human normal and malignant cells. This technique can be safely applied in chemotherapy for delivering drugs into tumor cells.

Effect of luteolin on apoptosis and vascular endothelial growth factor in human choroidal melanoma cells

AIM:To investigate the effects of luteolin on apoptosis,the cell cycle,and the expression and secretion of vascular endothelial growth factor(VEGF)in human choroidal melanoma cells(C918 and OCM-1).METHODS:C918 and OCM-1 cells cultured in vitro were treated with various concentrations of luteolin(0,5,10,15μmol/L).Cell growth was observed with an inverted microscope,and cell cycle arrest was detected by propidium iodide(PI)staining using flow cytometry.Apoptosis was detected by Hoechst33342 staining,and apoptosis rate was determined by Annexin V-FITC/PI experiments using flow cytometry.The expression of apoptosis-related proteins Bcl-2,Bax and VEGF was analyzed using Western blots.The levels of VEGF secreted by the cells into the supernatant was analyzed using ELISA.RESULTS:After treating with 5 to 15μmol/L luteolin for 48 h,the fusion degree of C918 and OCM-1 cells decreased,and more floating apoptotic cells appeared.Luteolin treatment increased the G0-G1 phase ratio of the C918 and OCM-1 cells,blocked cell cycle progression,and increased the apoptosis rate of the C918 and OCM-1 cells.Western blot showed that luteolin decreased the expression of Bcl-2 and VEGF in the C918 and OCM-1 cells and increased the expression of Bax protein.The ELISA results showed that 10 to 15μmol/L luteolin decreased the cell secretion of VEGF.CONCLUSION:Luteolin may induce apoptosis by regulating the levels of apoptosis-related proteins in C918 and OCM-1 cells.Luteolin can induce cell cycle arrest,decrease the expression of VEGF.

紫铆花素对人黑色素瘤细胞A375与人永生化角质形成细胞HaCaT共培养细胞生物学活性的影响

目的探讨紫铆花素对人黑色素瘤细胞A375与人永生化角质形成细胞HaCaT共培养细胞生物学活性的影响。方法建立A375细胞与HaCaT细胞的共培养细胞体系,实验分为对照组(等体积培养液),紫铆花素低、中、高剂量组(以下简称低、中、高剂量组,0.5,1.0,5.0μg/L)。采用四甲基偶氮噻唑蓝(MTT)法检测细胞活性;采用流式细胞仪检测细胞的周期分布和线粒体膜电位;采用实时荧光定量聚合酶链反应(qPCR)法检测干细胞因子(SCF)和其受体c-Kit,以及小眼畸形相关转录因子(MITF)的mRNA表达水平;采用Western blot法检测细胞酪氨酸酶相关蛋白1,2(TRP-1,TRP-2)及SCF,c-Kit,MITF的蛋白表达水平。结果与对照组比较,中、高剂量组细胞的增殖率均显著升高(P<0.01);与对照组比较,各剂量组G0/G1期细胞比例均显著降低,S期和G_(2)/M期细胞比例均显著升高(P<0.01),高线粒体膜电位细胞比例均显著升高(P<0.05或P<0.01),SCF,c-Kit,MITF的mRNA表达水平及SCF,c-Kit,MITF,TRP-1,TRP-2的蛋白表达水平均显著升高(P<0.05或P<0.01)。结论紫铆花素可能通过调节SCF,cKit,MITF的表达而影响A375细胞与HaCaT细胞共培养细胞的增殖、细胞周期和线粒体膜电位等细胞生物学活性。

Celecoxib in combination with retinoid CD437 inhibits melanoma A375 cell in vitro

This study aimed to investigate the effects of celecoxib,synthetic retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalenecarboxylicacid(CD437)and the combination of the two on cell proliferation,apoptosis,and cycle arrest of human malignant mela-noma A375 cells.3-(4,5-dimethylthiazol-2-yl)-2,5-di-phenyltetrazoliumbromide assay(MTT assay)was applied to determine the anti-proliferative effects of the drugs on human malignant melanoma A375 cells.Flow cytometry was performed to investigate the influence of the drugs on cell cycle and cell apoptosis.Both celecoxib and CD437 could inhibit the growth of human malignant melanoma A375 cells in a dose-dependent manner.Celecoxib at 80μmol/L inhibited proliferation,induced apoptosis and G2/M cell cycle arrest of human malignant melanoma A375 cells after treatment for 24 h[proliferation inhibiting rate:(50.2±2.51)%,apoptosis rate:(35.91±1.80)%].CD437 at 10μmol/L inhibited proliferation,induced apoptosis and G0/G1 cell cycle arrest of human malignant melanoma A375 cells after treatment for 24 h[proliferation inhibiting rate:(58.6±2.38)%,apoptosis rate:(28.03±0.77)%].Celecoxib in combination with CD437 could significantly enhance the effects of inhibiting proliferation and inducing apoptosis of human malignant melanoma A375 cells 24 h after treatment compared with the drug alone[proliferation inhibiting rate:(68.92±1.72)%,apop-tosis rate:(42.09±1.05)%,both P<0.05]and decrease the proportion of the S phase in the cell cycle.Celecoxib could inhibit the growth of human malignant melanoma A375 cells by inducing apoptosis and G2/M cycle arrest.CD437 could inhibit the growth of human malignant melanoma A375 cells by inducing apoptosis and G0/G1 cycle arrest.Celecoxib exhibited additive effects with CD437 on retarding the growth and inducing apoptosis of human malignant melanoma A375 cells.Celecoxib in combination with CD437 may become an effective method for prevention and treatment of human melanoma.

质子辐射对人恶性黑色素瘤A375细胞的DNA损伤影响研究

为研究质子辐射对人恶性黑色素瘤的杀伤效应,本研究利用北京HI-13串列加速器提供的15 MeV质子,以0、1、2、4、8 Gy剂量辐照A375细胞,以细胞克隆术和流式细胞术检测A375细胞的克隆形成率、周期阻滞及凋亡率,用免疫荧光法检测2 Gy辐照后细胞的γH2AX焦点数,并与相同条件下的γ射线辐射对比。结果表明,在1~8 Gy剂量下,随着剂量的增加,A375细胞的存活率下降,在4~8 Gy剂量下,细胞的存活率明显低于γ射线。辐照后12 h,细胞G2/M期阻滞随剂量的增加而增加,质子辐射诱导的周期阻滞强于γ射线;辐照后48 h,γ射线诱导的细胞周期阻滞已基本解除,但质子诱导的细胞周期阻滞除1 Gy外,2~8 Gy均未完全解除。辐射诱导的细胞凋亡随照射剂量的增加而增加,随着时间的延长,凋亡比例有所增加,且质子诱导的细胞凋亡率高于γ射线。辐照2 Gy后,γ射线和质子诱导的γH2AX焦点峰值均在照后1 h出现,质子辐射诱导的γH2AX焦点数和大小均高于γ射线。以上结果表明,质子辐射可有效杀伤恶性黑色素瘤A375细胞,在黑色素瘤治疗中有潜在应用价值。

Human Multipotent Stem Cell Proteins Induce Apoptosis in Skin Cancer Cells

Unique characteristics in fetal development include scar-less wound healing and the paucity of tumor formation. Recent studies have demonstrated that the embryonic microenvironment can reverse melanoma cells to a benign melanocyte phenotype. We bioengineered embryonic-like compositions and tested the anti-cancer activity of this material on a panel of skin cancer lines. To simulate the embryonic environment, neonatal fibroblasts were grown in hypoxic suspension cultures. The cells reverted back into multipotent stem cells as evidenced by the upregulation of SOX2, Oct4, NANOG, and KLF4 genes, and by the expression of stem cell-associated proteins including Nodal, Brachyury, Nestin, and Oct4. Cell Conditioned Media (CCM) and human Extracellular Matrix Proteins (hECM) produced by these cells were tested for their ability to reduce cell viability in skin cancer cell lines. In vitro studies with CCM and hECM show reduction in Squamous Cell Carcinoma (SCC), Basal Cell Carcinoma (BCC) and melanoma cell number through upregulation of caspases and induction of apoptosis. In the chick allantoic membrane assay, melanoma load was reduced by up to 80% with hECM treatment compared to vehicle treated controls (p 0.05). Similar inhibition was seen with SCC cells. In a xenograft mouse model of subcutaneous melanoma, tumor growth was inhibited by 70% - 90%. These data suggest that CCM and hECM have anti tumor potential and might offer a new treatment strategy in skin cancer.

In-Vitro Inhibition of Human Melanoma (BLM) Cell Growth by Progesterone Receptor Antagonist RU-486 (Mifepristone)

RU-486 is an abortifacient which is used to terminate early pregnancy. It acts by blocking progesterone receptor. In our earlier study with progesterone, RU-486 was used as a progesterone receptor antagonist to find out the mechanism of progesterone action on melanoma cells. Results indicated that the effect of progesterone was not mediated through progesterone receptor. In the course of experiments, it was observed that RU-486 by itself inhibited mouse melanoma cell growth. Further research work with RU-486 showed a dose dependent inhibition of human melanoma cell growth. The mechanism of inhibition of cell growth was due to apoptosis and this effect of RU-486 was neither mediated through progesterone receptor nor glucocorticoid receptor. This in-vitro study suggested that melanoma also could be a target for RU-486 action, apart from breast, ovary and prostate cancers.

紫菜多酚对人恶性黑色素瘤细胞A375增殖和诱导凋亡的影响及机制探讨

以紫菜为原料,通过乙醇溶剂提取、硅胶柱层析、高效液相制备色谱等步骤,得到紫菜多酚组分C1、C2、D1、D2四个组分.通过MTT法测定组分C1、C2对人恶性黑色素瘤细胞A375的增殖抑制作用,结果表明:组分C1、C2作用于A375细胞48 h的IC50分别为1.10、1.58 mg·m L-1.采用Annexin V/PI双染测定细胞凋亡情况发现,A375细胞经紫菜多酚组分C1处理后凋亡的细胞比例增加.经组分C1作用的A375细胞中黑色素含量和相对酪氨酸酶活力均得到提高,且与药物浓度呈正相关关系;透射电镜检测A375细胞超微结构的变化发现紫菜多酚组分C1可诱导A375细胞趋向正常分化.

全反式维A酸、阿维A和他扎罗汀对人黑色素瘤细胞A375凋亡和Bax/Bcl-2蛋白表达的影响及意义

目的探讨全反式维A酸(ATRA)、阿维A及他扎罗汀对人黑色素瘤细胞A375凋亡及Bax/Bcl-2蛋白表达的影响及其意义。方法采用体外培养和流式细胞仪检测细胞凋亡(AnnexinV-PI法),SABC免疫细胞化学方法检测细胞Bax/Bcl-2蛋白表达情况。结果浓度均为10-5mol/L的ATRA、阿维A及他扎罗汀能不同程度地诱导了人黑色素瘤细胞A375凋亡,其中阿维A作用最为显著,凋亡率13.42%,明显高于对照组、ATRA及他扎罗汀组(均P<0.05);其次为ATRA(5.03%,明显高于对照组及他扎罗汀组,P<0.05)和他扎罗汀组(凋亡率2.88%)。3种维A酸亦使A375细胞Bax蛋白阳性表达增强而Bcl-2蛋白阳性表达减弱(P<0.05),其中阿维A作用最强,其次为ATRA和他扎罗汀。结论维A酸促进A375细胞凋亡可能部分通过以线粒体为核心的凋亡途径。阿维A可能是防治黑色素瘤的有效药物。

β-榄香烯诱导人黑色素瘤A375细胞凋亡的研究

β-榄香烯是我国自主开发的二类非细胞毒性抗肿瘤药物,具有广谱、高效、低毒等优点,对肝癌、肺癌等多种恶性肿瘤均有较好的治疗效果,但对人皮肤肿瘤的研究尚无报道。基于此,就β-榄香烯对人恶性黑色素瘤A375细胞的抗肿瘤活性展开研究,发现β-榄香烯能够显著抑制A375细胞增殖(P<0.01),并在一定范围内呈浓度和时间依赖性,主要表现为β-榄香烯能够诱导细胞发生凋亡。进一步对相关凋亡蛋白进行Western-blot检测,发现β-榄香烯通过抑制细胞内AKT信号通路途径,调控Bcl-2家族蛋白,降低Bcl-2的表达,显著增加Bad的表达量,并激活部分caspase系列蛋白质的剪切活化,从而抑制A375细胞增殖,诱导细胞凋亡。

赤芍总苷抑制人黑色素瘤A375细胞株增殖作用的研究

目的观察赤芍总苷(TPG)对人黑色素瘤A375细胞增殖的影响及其作用机制。方法黑色素瘤A375细胞,分别加入12.5、25、50、100、200 mg/L TPG,对照组加等量0.9%氯化钠注射液,孵育48 h。采用四甲基偶氮唑蓝(MTT)方法测定细胞生长抑制率,用RT-PCR、Western blot法分别检测增殖细胞核抗原(PCNA)、P21、P27、P53 mRNA及其蛋白的表达水平。结果不同浓度(12.5、25、50、100、200 mg/L)TPG刺激后,对黑色素瘤细胞均具有明显的增殖抑制作用。100 mg/L TPG作用黑色素瘤细胞48 h,PCNA mRNA及其蛋白表达水平较对照组显著下降,而P21、P27、P53的mRNA及其蛋白表达水平较对照组显著上升,差异有统计学意义(P<0.01)。结论TPG抑制黑色素瘤A375细胞增殖,与下调PCNA表达及上调P21、P27、P53表达有关。

甘草素通过调控miRNA抑制人黑色素瘤A375细胞的侵袭转移

目的 :探讨甘草素对人黑色素瘤A375细胞侵袭转移的抑制作用及与miRNA相关调控机制。方法 :不同浓度甘草素处理24 h后,采用噻唑蓝(MTT)法测定细胞存活情况,确定甘草素对细胞无毒作用剂量;通过划痕试验和Transwell小室迁移、侵袭试验分别观察细胞的非定向迁移力和定向迁移侵袭力;miRNA芯片筛选差异表达的miRNA,q PCR方法验证hsa-miR-4534和hsa-miR-4487的下调表达;Western blot检测PTEN、p-AKT、AKT、MMP2和TIMP2蛋白表达。结果:10~100μmol/L剂量甘草素处理A375细胞24 h对细胞无明显损伤作用,划痕试验、Transwell小室迁移试验、侵袭试验显示甘草素能抑制A375细胞侵袭转移;甘草素可下调hsa-miR-4534和hsa-miR-4487的表达,上调PTEN、TIMP2表达水平,降低p-AKT、MMP2的表达水平。结论:甘草素通过下调hsa-miR-4534和hsa-miR-4487表达,进而上调PTEN和TIMP2靶基因的表达水平,阻碍p-AKT信号通路并降低MMP2蛋白表达,从而发挥抑制人黑色素瘤A375细胞侵袭和转移的作用。

蛋白激酶C在吴茱萸碱诱导A375-S2细胞死亡中的作用

目的研究蛋白激酶C(proteinkinaseC,PKC)在吴茱萸碱(evodiamine)诱导的A375-S2细胞死亡过程中的作用。方法TUNEL法检测吴茱萸碱诱导细胞凋亡的比例。MTT法测定药物对A375-S2细胞的细胞毒作用。Westernblotting法分析药物作用后对ERK及其磷酸化蛋白和Bcl-2家族蛋白的影响。结果吴茱萸碱诱导A375-S2细胞的死亡在24h以前以凋亡为主。PKC抑制剂staurosporine和ERK抑制剂PD98059均能促进吴茱萸碱诱导的A375-S2细胞死亡。吴茱萸碱能够抑制PKC的活力,下调ERK及其磷酸化蛋白的表达水平,并使Bax/Bcl-2表达比例上升。而staurosporine对吴茱萸碱抑制PKC活力,降低ERK及其磷酸化蛋白和Bcl-2的表达有进一步增强的作用。结论在吴茱萸碱诱导的A375-S2细胞死亡中,PKC位于ERK和Bcl-2的上游发挥其调节作用。

补骨脂注射液联合NB-UVB对人黑素瘤A375细胞增殖及黑素合成的影响

目的通过观察补骨脂注射液联合窄谱中波紫外线(NB-UVB)对人黑素瘤A375细胞的增殖、黑素的合成以及酪氨酸酶活性的影响,探讨两者协同治疗白癜风的可能机制。方法选择一定浓度的补骨脂注射液(稀释后浓度为0.5%)联合一定剂量的NB-UVB(22m J/cm2)共同作用于人黑素瘤A375细胞后,通过MTT法观察其对人黑素瘤A375细胞细胞增殖的影响,Na OH裂解法测定黑素的含量,多巴氧化法测定酪氨酸酶活性的变化。结果补骨脂注射液+NB-UVB组中A375细胞培养至48h,72h后检测到的细胞增殖情况与单一补骨脂注射液组、NB-UVB组及空白组相比较,差异有统计学意义(P<0.05)。补骨脂注射液+NB-UVB组均显示可上调细胞内酪氨酸酶的活性及黑素的生成量,且与各实验干预组及空白组比较,差异有统计学意义(P<0.05)。结论一定浓度的补骨脂注射液(稀释后浓度为0.5%)联合一定剂量的NB-UVB(22m J/cm2)可以协同促进人黑素瘤A375细胞的增殖,上调细胞酪氨酸酶活性,从而达到促进黑素合成的效果。

腺病毒介导的nm23-H1对人恶性黑色素瘤A375体外抑制作用的研究

目的观察Ad-GFP-nm23-Hl抑制人恶性黑色素瘤(Malignant melanoma,MM)A375细胞生长和转移的作用,为后期nm23-Hl基因和腺病毒载体用于MM及其它肿瘤的基因治疗提供一定的理论和方法。方法采用MTT法检测Ad-GFP-nm23-Hl,对A375细胞增殖力的影响,用细胞基质胶黏附实验黏附力和侵袭能力实验来分别检测Ad-GFP-nm23-Hl,对A375细胞粘附力和侵袭能力的影响。结果Ad-GFP-nm23-Hl可以明显抑制A375细胞的增殖、黏附和侵袭能力,其抑制作用呈剂量—效应关系。结论Ad-GFP-nm23-Hl,对人恶性黑色素瘤A375细胞的生长和转移具有抑制作用。

黄芩苷对人黑色素瘤A375细胞增殖的影响

目的:探讨黄芩苷对人黑色素瘤A375细胞株体外增殖的抑制作用。方法:选用人黑色素瘤A375细胞进行体外培养,以不同浓度的黄芩苷分别处理黑色素瘤A375细胞,连续6天使用倒置显微镜进行观察,计数,绘制生长曲线;以不同浓度(0.1～50μmol/L)的黄芩苷分别处理黑色素瘤A375细胞细胞24、48、72h后,用MTT法检测细胞生长抑制率;流式细胞仪检测细胞凋亡率。结果:生长曲线及MTT法显示黄芩苷对黑色素瘤A375细胞有抑制作用,并呈剂量和时间依赖性;流式细胞仪检测到细胞在黄芩苷作用后,细胞凋亡率增加。结论:黄芩苷对人黑色素瘤A375细胞具有明显抑制作用,细胞凋亡可能是其机制之一。

miR-146a对人黑色素瘤A375细胞增殖和侵袭的影响及作用机制

目的探讨微小RNA-146a(miR-146a)对人黑色素瘤A375细胞增殖与侵袭能力的影响及可能机制。方法利用阳离子脂质体LipofectamineTM2000将miR-146a模拟物或抑制剂转染入黑色素瘤A375细胞,使miR-146a过表达或低表达,采用MTT检测细胞活力变化,应用Transwell小室法检测A375细胞侵袭能力的变化。根据生物信息学软件预测FBXL10为miR-146a的下游靶基因,双荧光素酶报告分析进行验证。分别采用实时qPCR与Western blotting检测转染后各组A375细胞FBXL10 mRNA与蛋白的表达水平。结果与对照组比较,miR-146a模拟物能够显著抑制A375细胞增殖和侵袭能力(均P<0.05)。双荧光素酶报告分析结果显示,FBXL10为miR-146a的下游靶基因,miR-146a过表达可显著降低FBXL10蛋白与mRNA的表达水平;miR-146a抑制剂的作用则与之相反。结论miR-146a过表达能够抑制A375细胞增殖和侵袭能力,其作用机制可能与降低FBXL10表达相关。