Trametinib boosts palbociclib’s efficacy in breast cancer via autophagy inhibition

Breast cancer,a predominant global health issue,requires ongoing exploration of new therapeutic strategies.Palbociclib(PAL),a well-known cyclin-dependent kinase(CDK)inhibitor,plays a critical role in breast cancer treatment.While its efficacy is recognized,the interplay between PAL and cellular autophagy,particularly in the context of the RAF/MEK/ERK signaling pathway,remains insufficiently explored.This study investigates PAL’s inhibitory effects on breast cancer using both in vitro(MCF7 and MDA-MB-468 cells)and in vivo(tumor-bearing nude mice)models.Aimed at elucidating the impact of PAL on autophagic processes and exploring the potential of combining it with trametinib(TRA),an MEK inhibitor,our research seeks to address the challenge of PAL-induced drug resistance.Ourfindings reveal that PAL significantly decreases the viability of MCF7 and MDA-MB-468 cells and reduces tumor size in mice while showing minimal cytotoxicity in MCF10A cells.However,PAL also induces protective autophagy,potentially leading to drug resistance via the RAF/MEK/ERK pathway activation.Introducing TRA effectively neutralized this autophagy,enhancing PAL’s anti-tumor efficacy.A combination of PAL and TRA synergistically reduced cell viability and proliferation,and in vivo studies showed notable tumor size reduction.In conclusion,the PAL and TRA combination emerges as a promising strategy for overcoming PAL-induced resistance,offering a new horizon in breast cancer treatment.

Complete response of metastatic BRAF V600-mutant anaplastic thyroid cancer following adjuvant dabrafenib and trametinib treatment:A case report

BACKGROUND Anaplastic thyroid cancer(ATC)is a rare but aggressive type of thyroid carcinoma.BRAF V600E-mutation,which is found in 10%-50%of ATCs,is associated with poor prognosis.A recent clinical trial reported a substantial clinical benefit of concomitant treatment of dabrafenib(BRAF inhibitor)and trametinib(MEK inhibitor)for treating BRAF V600E-mutant ATC.However,reports on patients with ATC treated with this regimen following surgery are lacking.CASE SUMMARY We report the case of a 63-year-old female patient diagnosed with BRAF V600Emutant ATC.Following three surgeries—total thyroidectomy,total laryngectomy,and neck dissection—she was diagnosed with lung metastasis during follow-up.The metastatic ATC was successfully treated with dabrafenib and trametinib.The patient achieved a complete response at the 32-mo follow-up.CONCLUSION Adjuvant chemotherapy with dabrafenib plus trametinib is efficacious for treatment and prevention of recurrent ATC with BRAF mutation following surgery.

Trametinib and dactolisib but not regorafenib exert antiproliferative effects on rat pancreatic stellate cells

BACKGROUND： Modulation of the stroma response is considered a promising approach for the treatment of chronic pancreatitis and pancreatic cancer. The aim of this study was to evaluate the effects of three clinically available small molecule kinase inhibitors, regorafenib, trametinib and dactolisib, on effector functions of activated pancreatic stellate cells （PSCs）, which play a key role in pancreatic fibrosis.

Synthetic lethal short hairpin RNA screening reveals that ring finger protein 183 confers resistance to trametinib in colorectal cancer cells

Background: The mitogen-activated extracellular signal-regulated kinase 1/2(MEK1/2) inhibitor trametinib has shown promising therapeutic effects on melanoma, but its efficacy on colorectal cancer(CRC) is limited. Synthetic lethality arises with a combination of two or more separate gene mutations that causes cell death, whereas individual mutations keep cells alive. This study aimed to identify the genes responsible for resistance to trametinib in CRC cells,using a synthetic lethal short hairpin RNA(shRNA) screening approach.Methods: We infected HT29 cells with a pooled lentiviral shRNA library and applied next-generation sequencing to identify shRNAs with reduced abundance after 8-day treatment of 20 nmol/L trametinib. HCT116 and HT29 cells were used in validation studies. Stable ring finger protein 183(RNF183)-overexpressing cell lines were generated by pcDNA4-myc/his-RNF183 transfection. Stable RNF 183-knockdown cell lines were generated by infection of lentiviruses that express RNF183 shRNA, and small interference RNA(siRNA) was used to knock down RNF183 transiently.Quantitative real-time PCR was used to determine the mRNA expression. Western blotting, immunohistochemical analysis, and enzyme-linked immunosorbent assay(ELISA) were used to evaluate the protein abundance. MTT assay,colony formation assay, and subcutaneous xenograft tumor growth model were used to evaluate cell proliferation.Results: In the primary screening, we found that the abundance of RNF183 shRNA was markedly reduced after treatment with trametinib. Trametinib induced the expression of RNF183, which conferred resistance to drug-induced cell growth repression and apoptotic and non-apoptotic cell deaths. Moreover, interleukin-8(IL-8) was a downstream gene of RNF183 and was required for the function of RNF183 in facilitating cell growth. Additionally, elevated RNF183 expression partly reduced the inhibitory effect of trametinib on IL-8 expression. Finally, xenograft tumor model showed the synergism of RNF183 knockdown and trametinib in repressing the growth of CRC cells in vivo.Conclusion: The RNF183-IL-8 axis is responsible for the resistance of CRC cells to the MEK1/2 inhibitor trametinib and may serve as a candidate target for combined therapy for CRC.

Radiation recall dermatitis with dabrafenib and trametinib: A case report

BACKGROUND Radiation recall dermatitis has been defined as the "recalling" by skin of previous radiation exposure in response to the administration of certain response-inducing drugs. Although the phenomenon is relatively well known in the medical world,an exact cause has not been documented.CASE SUMMARY Here, we report the rare occurrence of radiation recall dermatitis after palliative radiotherapy for bone metastases in a metastatic melanoma patient treated with a combination of dabrafenib and trametinib.CONCLUSION We present a case of radiation recall dermatitis after completion of palliative radiotherapy while being treated with a combination of dabrafenib and trametinib. This is a very rare toxic event, and there is insufficient data to describe prevention strategies. Increased awareness and reporting of cases will help to better explain the association between targeted therapy and the radiation recall phenomenon.

Asian Case of Metastatic Melanoma in Which a Complete Response Was Maintained after Discontinuation of Dabrafenib and Trametinib

A 54-year-old man diagnosed with metastatic melanoma of the right inguinal node with occult primary developed liver and bone metastases. The combination of dabrafenib plus trametinib was initiated, and a complete response (CR) was achieved 24 months after starting treatment. One month later, the target therapy was discontinued at the patient’s decision, and he has remained free from progression for 21 months since discontinuation. To the extent of our knowledge, real-world data in Asian melanoma concerning the discontinuation of dabrafenib plus trametinib after achieving CR have not been published;therefore, our case is a meaningful one for considering to cease target drugs and to rescue their financial toxicity.

Fast reaction and long duration--application of dabrafenib plus trametinib in treatment of metastatic melanoma with B-Raf V600E mutation:A case report

The prognosis of patients with advanced melanoma is poor.The five-year recurrence rate is approximately 70%,whereas the overall survival rate is only 4%-10%.We report the case of a 61-year-old male patient with metastatic melanoma(B-Raft).The tumor load of the patient was significantly reduced after the application of dabrafenib plus trametinib(“DtT”)and radiotherapy.Further,it is suggested that medical staff should conduct a comprehensive analysis of the patient’s condition when dealing with adverse events(AEs)associated with such malignant tumors to provide evidence for adopting the appropriate targeted treatment or radiotherapy and nursing mode and achieve the best treatment effect.

达拉非尼联合曲美替尼致发热综合征1例并文献复习

1例69岁女性患者,因“左足恶性黑色素瘤”给予甲磺酸达拉非尼胶囊(150 mg,每天2次)联合曲美替尼片(2 mg,每天1次)。服药后第2天出现发热,体温最高达39℃,无畏寒、寒战等伴随症状,考虑为达拉非尼联合曲美替尼所致发热综合征。予患者布洛芬胶囊(400 mg,每6 h 1次)并暂停达拉非尼胶囊24 h,后体温降至正常;重启达拉非尼胶囊并减量(75 mg,每天2次)治疗后未出现明显发热。药师建议在患者可耐受的情况下,可将达拉非尼胶囊加量(150 mg,每天1次+75 mg,睡前),若体温超过40℃或伴明显寒战,可通过中断给药或预防性使用类固醇(泼尼松7.5~25 mg·d^(-1)或地塞米松0.5~4 mg·d^(-1))改善症状;若症状仍无法改善则需调整两药剂量,达拉非尼最终剂量不低于50 mg,每天2次,曲美替尼剂量不低于1.0 mg,每天1次。经院外随访,患者未再出现高热、寒战等发热综合征症状。

MEK inhibitors for the treatment of extracranial arteriovenous malformations

Arteriovenous malformations(AVMs)are serious congenital vascular anomalies in which the arteries connect directly with veins without capillaries.This condition will continue to worsen without proper intervention and cause ulcers,repeated hemorrhages,and even cardiac insufficiency.Primary treatment options for AVMs include surgery and interventional treatment;however,they are associated with high risk and recurrence rates.Recent studies revealed that excessive activation of the Ras/MAPK pathway can induce the formation and development of peripheral AVM,whereas MEK inhibitors can effectively control nidus progression,making them a potential novel treatment for AVM.This review provides an up-to-date overview of correlated laboratory and clinical research to provide information for further research and clinical practice.

达拉非尼联合曲美替尼在黑色素瘤治疗中致皮肤系统不良反应的文献分析

目的:分析达拉非尼联合曲美替尼治疗黑色素瘤致皮肤系统不良反应(ADR)的发生情况及临床特点,为临床安全用药提供参考。方法:检索Web of Science、PubMed、知网和万方数据库,收集国内外相关个案报道并进行分析总结。结果:共筛选出有效文献31篇,共38例次,患者年龄主要为31~80岁(89.47%);ADR多发生在用药后90 d内(60.52%);主要临床表现为痤疮样皮疹(18.42%)、肉芽肿性皮炎(13.16%)、脂膜炎(10.53%)、纹身并发症(10.53%)及结节性红斑病变(10.53%);34例患者皮肤ADR痊愈或好转,其中2例永久停用了达拉非尼与曲美替尼,10例继续联合治疗,12例暂停联合治疗,其中11例患者好转或痊愈后重启联合治疗。在重启或继续使用联合治疗的患者中,10例再次出现ADR。结论:本研究中,达拉非尼联合曲美替尼致皮肤系统ADR表现出不同的发生率和特征,且免疫治疗后进行靶向治疗可能增加严重皮肤ADR发生风险。临床在联合使用时应加强用药监测,及时发现ADR并采取适当的防治措施,同时严密监测重启或继续用药所致ADR,确保用药安全。

抑制脉管畸形的相关靶向药物研究进展

脉管畸形是一种先天性疾患,主要发生在头颈部,其无法自行消退,且随着患者的生长而逐渐加重。脉管畸形的传统治疗方式包括:激光治疗、硬化治疗、介入栓塞、手术切除等。但是对于一些范围较大的病变,传统治疗方式效果不佳。随着分子遗传学的发展,基因突变目前被认为是脉管畸形发生的根本原因,基因突变引起的相关通路的活化进一步促进了脉管畸形病变的进展。低流速脉管畸形主要涉及磷脂酰肌醇3⁃激酶(phosphatidylinositol 3⁃kinase,PI3K)/蛋白激酶B(protein kinase B,AKT)/哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)通路的激活;而高流速的脉管畸形主要涉及大鼠肉瘤(rat sarcoma,RAS)/快速加速纤维肉瘤(rapidly accelerated fibrosarcoma,RAF)/促分裂原活化蛋白激酶激酶(mitogen⁃activated protein kinase kinase,MAPKK)/细胞外信号调节激酶(extracellular⁃signalregulated protein kinase,ERK)通路的激活。目前,针对相关基因突变及信号通路的靶向药物也逐渐应用到脉管畸形的治疗中。mTOR抑制剂——雷帕霉素被广泛应用于低流速脉管畸形的靶向治疗;PI3K抑制剂——阿培利司在静脉畸形的治疗中也具有良好的前景;MAPKK抑制剂——曲美替尼在动静脉畸形的治疗中取得了良好的疗效。因此,传统治疗辅以靶向药物的方式或为脉管畸形治疗带来新的突破。

基于FAERS数据库的甲磺酸达拉非尼联合曲美替尼致药品不良事件信号挖掘

目的:探讨甲磺酸达拉非尼联合曲美替尼上市后的药品不良事件信号,为临床安全用药提供参考。方法:利用OpenVigil 2.1-MedDRA平台,收集美国食品药品监督管理局不良事件报告系统(FAERS)数据库中有关甲磺酸达拉非尼与曲美替尼联合应用的不良事件数据,截至2022年第2季度。采用比例失衡算法分析不良事件信号,分析不良事件上报的人群特征以及频数较高和新发的不良事件信息。结果:共获取甲磺酸达拉非尼与曲美替尼联合应用的不良事件报告9712例,涉及男性患者4555例(占46.90%),女性患者3921例(占40.37%);18~<65岁患者较多(2503例,占25.77%);上报数据主要源于美国(4287例,占44.14%);严重的不良事件主要包括死亡(2100例,占21.62%)、导致住院或住院时间延长(1889例,占19.45%)。发生频数较高的不良事件主要有恶性肿瘤转移,发热和皮肤毒性等;新发的不良事件主要有吞咽困难、惊厥和脂膜炎等。结论:临床联合应用甲磺酸达拉非尼与曲美替尼时,应对发生频数较高以及新发的不良事件予以重视。在使用药物治疗前、治疗中及随访阶段,均应做好相关监测工作,有效保障患者用药安全。

胡黄连苷Ⅱ联合曲美替尼对HT-29细胞凋亡和上皮细胞间质转化的影响

目的:研究胡黄连苷Ⅱ联合曲美替尼通过miR-4319对结直肠癌细胞HT-29凋亡和上皮细胞间质转化(EMT)的影响。方法:将结直肠癌细胞HT-29分成6组,分别为对照组、曲美替尼组、胡黄连苷Ⅱ组、联合组、miR-NC抑制组、miR-4319抑制组,n=9。采用CCK-8实验检测细胞增殖,流式细胞术检测细胞凋亡,Western Blotting法检测Vimentin、E-cadherin、Bax、C-Caspase-3蛋白表达,qRT-PCR检测miR-4319表达。比较6个组的检测结果。结果:与对照组比较,曲美替尼组、胡黄连苷Ⅱ组、联合组的细胞成活率和Vimentin的表达均减少(均P<0.05),而凋亡率和Bax、C-Caspase-3、E-cadherin的表达均增加(均P<0.05);与miR-NC抑制组比较,miR-4319抑制组的细胞成活率、Vimentin的表达均显著增加(均P<0.05),细胞凋亡率和Bax、C-Caspase-3、E-cadherin蛋白表达却显著减少(均P<0.05);qRT-PCR结果显示,与对照组比较,曲美替尼组、胡黄连苷Ⅱ组细胞中miR-4319的表达增多(均P<0.05)。结论:胡黄连苷Ⅱ联合曲美替尼通过上调miR-4319诱导结直肠癌细胞HT-29凋亡,并抑制细胞EMT。

Pharmacological drug screening to inhibit uveal melanoma metastatic cells either via EGF-R, MAPK, mTOR or PI3K

AIM: To screen five potential pharmacological substances specifically targeting EGF-R, MAPK, mTOR, or PI3K for their antiproliferative effects, possible impact on cell viability, as well as cell death rates on three different uveal melanoma metastasis cell lines in vitro. METHODS: Three different uveal melanoma metastasis cell lines(OMM2.5, OMM2.3, and OMM1), that originated from human hepatic and subcutaneous metastasis, were exposed to inhibitors of different targets: erlotinib(EGF-R), everolimus(mTOR), selumetinib(MAPK), trametinib(MAPK) or the alkylphosphocholine erufosine(PI3K). Cell viability was assessed with a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide(XTT) dye reduction assay after 24 h of treatment. Antiproliferative effects were evaluated separately after a 72-hour incubation of the cells with the pharmacological substance. Subsequently, the IC_(50) was calculated. Tumor cell death was investigated using a double stain apoptosis detection assay. RESULTS: Selumetinib, trametinib, and erufosine significantly decreased cell viability of all OMM cell lines(P<0.04). In addition, selumetinib and trametinib showed a significant inhibition of cell proliferation(P<0.05). Everolimus and erlotinib solely inhibited cell proliferation at the used concentrations(P<0.05). Besides an increase of necrotic cells after erufosine treatment(P<0.001), no changes in the number of dead cells for the other substances were observed.CONCLUSION: The preliminary drug screening demonstrates five new candidates, successfully targeting the canonical MAPK/ERK and PI3K/AKT/m TOR pathways in uveal melanoma metastasis cells in vitro. Hence, these findings provide an experimental basis to explore future single or combined therapy strategies for metastatic uveal melanoma.

Choroidal thickening with serous retinal detachment in BRAF/MEK inhibitor-induced uveitis:A case report

BACKGROUND Immune checkpoint inhibitors have revolutionized the treatment of patients with unresectable metastatic malignant melanoma.In addition to systemic side effects,several usually mild ocular adverse effects have been reported.We report a case of rarely reported vision-threatening bilateral panuveitis with serous retinal detachment,thickened choroid,and chorioretinal folds associated with dabrafenib and trametinib targeted therapy for B-Raf proto-oncogene serine/threonine kinase(BRAF)mutant metastatic cutaneous melanoma.CASE SUMMARY A 59-year-old female patient with metastatic melanoma treated with dabrafenib and trametinib presented with blurry vision and central scotoma lasting for 3 d in both eyes.Clinical examination and multimodal imaging revealed inflammatory cells in the anterior chamber,mild vitritis,bullous multiple serous retinal detachments,and chorioretinal folds in both eyes.Treatment with dabrafenib and trametinib was suspended,and the patient was treated with topical and intravenous corticosteroids followed by oral corticosteroid treatment with a tapering schedule.One and a half months after the disease onset,ocular morphological and functional improvement was noted.Due to the metastatic melanoma dissemination,BRAF/mitogen-activated protein kinase inhibitors were reintroduced and some mild ocular adverse effects reappeared,which later subsided after receiving oral corticosteroids.CONCLUSION Patients on combination therapy with dabrafenib and trametinib may rarely develop severe bilateral panuveitis with a good prognosis.Further studies have to establish potential usefulness of ophthalmological examination for asymptomatic patients.Furthermore,appropriate guidelines for managing panuveitis associated with dabrafenib and trametinib should be established.

同源盒基因2在黑色素瘤细胞对于曲美替尼耐药中的作用

目的:研究同源盒基因2(MSX2)在黑色素瘤细胞A375对于曲美替尼耐药中的作用机制。方法:构建曲美替尼耐药的A375细胞株(A375-AR),曲美替尼干预A375和A375-AR后采用CCK-8检测细胞活力,流式细胞术检测细胞凋亡率,蛋白免疫印迹法(Western blot)检测细胞中Bcl-2、Bax、Caspase-3、Caspase-9的表达以及MSX2的表达。采用小干扰RNA(siRNA)沉默A375-AR中MSX2基因,设计A375、A375-AR、A375-AR-MSX2,曲美替尼干预后,CCK-8检测细胞活力,流式细胞术检测细胞凋亡率,Western blot检测细胞中Bcl-2、Bax、Caspase-3、Caspase-9的表达以及MSX2的表达。构建MSX2过表达的A375细胞系(A375-OE),设置A375、A375-OE和A375-AR组,曲美替尼干预后,CCK-8检测细胞活力,流式细胞术检测细胞凋亡率,Western blot检测细胞中Bcl-2、Bax、Caspase-3、Caspase-9的表达以及MSX2的表达。结果:A375-AR对 1.8 nmol/L的曲美替尼耐药,采用 1.8 nmol/L曲美替尼干预后,A375细胞活力和细胞凋亡率显著高于A375-AR,A375细胞中Bcl-2基因表达水平低于A375-AR,而Bax、Caspase-3、Caspase-9的表达水平高于A375-AR。A375-AR沉默MSX2后,细胞对于曲美替尼敏感性显著增高,且细胞活力下调,凋亡率上调,细胞中Bcl-2表达下调,Bax、Caspase-3、Caspase-9的表达上调。A375过表达MSX2后,细胞对于曲美替尼敏感性显著下调,细胞活力上调,凋亡率下调,细胞中Bcl-2表达上调,Bax、Caspase-3、Caspase-9的表达下调。结论:MSX2基因可以诱导黑色素瘤细胞对于曲美替尼的耐药,是治疗黑色素瘤耐药的潜在靶点。

西妥昔单抗联合曲美替尼对人结肠癌细胞增殖和凋亡的影响

目的研究西妥昔单抗、曲美替尼在体外对不同KRAS和BRAF基因型的人结肠癌细胞增殖和凋亡的影响,以及联合用药是否具有协同增效作用。方法采用三种不同基因型的结肠癌细胞系HT29(KRAS-WT,BRAFV600E)、SW48(KRASWT,BRAF-WT)、SW480(KRASG12V,BRAF-WT),将每种细胞系随机分为对照组、西妥昔单抗组(200μg/ml)、曲美替尼组(1 nmol/L)、两药联合组,体外培养72h后,细胞增殖抑制实验(CCK8方法)检测细胞增殖率,流式细胞技术(Annexin V-PI标记方法)检测细胞凋亡率。结果细胞增殖抑制结果:西妥昔单抗单药对SW480、HT-29细胞增殖率无显著影响(P>0.05),对SW48细胞增殖抑制作用显著(P<0.001);曲美替尼单药对三种细胞均有显著的增殖抑制作用(P<0.01);两药联合后可进一步抑制三种细胞的增殖(P<0.05)。细胞凋亡结果:西妥昔单抗单药对三株细胞凋亡率的影响无统计学差异(P>0.05);曲美替尼单药对SW480、HT-29有显著诱导凋亡作用(P<0.05),对SW48诱导凋亡作用不明显(P>0.05);联合用药组较西妥昔单抗组HT-29、SW480细胞凋亡率升高(P<0.05),SW48的凋亡率变化无统计学差异(P>0.05);三种细胞两药联合组与曲美替尼组的凋亡率对比均无统计学差异(P>0.05)。结论西妥昔单抗与曲美替尼联合可以有效抑制结肠癌细胞增殖和诱导凋亡,显著提高KRAS、BRAF突变型结肠癌细胞对西妥昔单抗的药物敏感性,对KRAS、BRAF野生型结肠癌细胞的抗肿瘤作用也有一定程度的改善,两药联合在体外具有协同增效的抗肿瘤作用。

隐丹参酮联合曲美替尼诱导胃癌细胞凋亡作用及其机制

目的 研究隐丹参酮增强MEK抑制剂曲美替尼诱导胃癌细胞MGC803凋亡的作用及其分子机制.方法 选用对数生长期的MGC803细胞,将其分为对照组、隐丹参酮组、曲美替尼组和隐丹参酮组/曲美替尼组联合用药组.采用CCK-8法检测隐丹参酮对曲美替尼增殖的影响,PI/Annexin-V双标记流式细胞术检测凋亡率的变化,Western blot检测STAT3及ERK等激酶的变化以及凋亡相关蛋白Caspase-3、Caspase-9和PARP的水平.结果 隐丹参酮显著增强曲美替尼对MGC803细胞的增殖抑制和凋亡诱导作用,细胞的促凋亡蛋白Caspase-3、Caspase-9和PARP显著激活;曲美替尼可显著抑制MGC803细胞ERK磷酸化水平,但同时可见STAT3磷酸化水平明显升高,而隐丹参酮联合曲美替尼可同时显著抑制ERK和STAT3的磷酸化水平.结论 STAT3在曲美替尼作用胃癌细胞MGC803的过程中被显著激活,联合应用STAT3抑制剂隐丹参酮可逆转STAT3的活化,从而增强曲美替尼诱导MGC803凋亡作用.本研究为MEK抑制剂曲美替尼和STAT3抑制剂隐丹参酮联合治疗胃癌提供了新的实验依据,为胃癌的临床治疗提供新的选择.

曲美替尼与GSK2126458联合用药逆转结直肠癌SW480细胞的耐药

近年来,肿瘤靶向药物因其特异性强与对正常细胞损伤小等特点,已成为癌症治疗的热点药物。但由肿瘤异质性导致的靶向药物的耐受现象,成为癌症治疗需要解决的难题之一。为解决单一药物的耐受现象,可以通过药物组合来达到理想的治疗效果。本课题以结直肠癌为研究对象,评估8种结直肠癌细胞对30种靶向药物的敏感性,并筛选可逆转耐药的药物组合,探究药物组合的作用。通过MTT实验测定细胞存活率,计算IC50值进行敏感性分析,敏感标准为IC50值≤100 nmol/L。对敏感的单药进行组合筛选,选取细胞存活率最小的组合。采用流式细胞术和Western印迹检测联合用药对细胞凋亡及MAPK、PI3K通路相关蛋白质表达水平的影响。MTT结果显示,结直肠癌SW480细胞耐受30种肿瘤靶向药物,经联合用药筛选,SW480细胞对曲美替尼与GSK2126458组合最为敏感,与对照组和单药组相比,该组合可使SW480细胞凋亡明显增加。免疫印迹结果显示,ERK、Akt和mTOR磷酸化水平降低,Cleaved PARP表达增加。上述结果表明,8种结直肠癌细胞存在不同程度耐受靶向抑制剂的现象,曲美替尼与GSK2126458联合应用可逆转结直肠癌SW480细胞的耐药现象。

MEK1/2抑制剂曲美替尼对体外多房棘球蚴原头节的作用研究

目的研究MEK1/2抑制剂曲美替尼对体外多房棘球绦虫(Echinococcus multilocularis,Em)活性的影响,探讨MEK1/2作为治疗泡型棘球蚴病靶点的可能性。方法建立Em空白对照组、DMSO及1μmol/L、50μmol/L、100μmol/L曲美替尼组,利用活力染色与扫描电镜(scanning electron microscope,SEM)分别观察虫体活性及体表结构变化;以Swiss Model同源建模合理构建Em MEK1/2分子的三级结构进行分析。结果1μmol/L曲美替尼干预3 d、6 d、9 d的原头节活性分别为(84.72±0.27)%、(87.32±2.01)%、(85.12±3.64)%,低于相同时间DMSO组,且差异有统计学意义(t>2.78,P<0.05);当1μmol/L曲美替尼干预时间延长至12 d,原头节活性降至(37.82±2.12)%,与DMSO组比较差异具有统计学意义(t=32.90,P<0.01)。SEM和活力染色显示曲美替尼组虫体活性与干预浓度成正比,同源建模结果显示Em与人MEK1/2分子具有较高的同源性。结论综合分析活力染色、SEM与同源建模结果,证实体外1μmol/L的MEK1/2抑制剂曲美替尼对虫体活性具有较好的抑制作用,为临床治疗提供了理论依据。