Receptor tyrosine kinases(RTKs)such as the epidermal growth factor receptor(EGFR)regulate cellular homeostatic processes.EGFR activates downstream signaling cascades that promote tumor cell survival,proliferation and ...Receptor tyrosine kinases(RTKs)such as the epidermal growth factor receptor(EGFR)regulate cellular homeostatic processes.EGFR activates downstream signaling cascades that promote tumor cell survival,proliferation and migration.Dysregulation of EGFR signaling as a consequence of overexpression,amplification and mutation of the EGFR gene occurs frequently in several types of cancers and many become dependent on EGFR signaling to maintain their malignant phenotypes.Consequently,concerted efforts have been mounted to develop therapeutic agents and strategies to effectively inhibit EGFR.However,limited therapeutic benefits to cancer patients have been derived from EGFR-targeted therapies.A well-documented obstacle to improved patient survival is the presence of EGFR-inhibitor resistant tumor cell variants within heterogeneous tumor cell masses.Here,we summarize the mechanisms by which tumors resist EGFR-targeted therapies and highlight the emerging role of microRNAs(miRs)as downstream effector molecules utilized by EGFR to promote tumor initiation,progression and that play a role in resistance to EGFR inhibitors.We also examine evidence supporting the utility of miRs as predictors of response to targeted therapies and novel therapeutic agents to circumvent EGFR-inhibitor resistance mechanisms.展开更多
The introduction of immune-checkpoint blockade in the cancer therapy led to a paradigm change of the management of late stage cancers. There are already multiple FDA approved checkpoint inhibitors and many other agent...The introduction of immune-checkpoint blockade in the cancer therapy led to a paradigm change of the management of late stage cancers. There are already multiple FDA approved checkpoint inhibitors and many other agents are undergoing phase 2 and early phase 3 clinical trials. The therapeutic indication of immune checkpoint inhibitors expanded in the last years, but still remains unclear who can benefit. Micro RNAs are small RNAs with no coding potential. By complementary pairing to the 3' untranslated region of messenger RNA, microRNAs exert posttranscriptional control of protein expression. A network of microRNAs directly and indirectly controls the expression of checkpoint receptors and several microRNAs can target multiple checkpoint molecules,mimicking the therapeutic effect of a combined immune checkpoint blockade. In this review, we will describe the microRNAs that control the expression of immune checkpoints and we will present four specific issues of the immune checkpoint therapy in cancer:(1) imprecise therapeutic indication,(2) difficult response evaluation,(3) numerous immunologic adverse-events, and(4)the absence of response to immune therapy. Finally, we propose microRNAs as possible solutions for these pitfalls. We consider that in the near future microRNAs could become important therapeutic partners of the immune checkpoint therapy.展开更多
目的人分化抑制因子3(inhibitor of differentination 3,Id3)基因在A549细胞中的外源性表达能抑制细胞生长并诱导细胞凋亡。文中旨在构建靶向人Id3基因的微小分子RNA(miRNA)表达载体,观察miRNA对A549细胞中Id3表达的下调作用,为进一步探...目的人分化抑制因子3(inhibitor of differentination 3,Id3)基因在A549细胞中的外源性表达能抑制细胞生长并诱导细胞凋亡。文中旨在构建靶向人Id3基因的微小分子RNA(miRNA)表达载体,观察miRNA对A549细胞中Id3表达的下调作用,为进一步探讨Id3基因在A549细胞生长调控中的作用机制提供一定实验依据。方法依据miRNA设计原则,针对人Id3基因的mRNA序列,设计并合成编码miRNA的2条寡核苷酸序列,经退火成互补双链,再克隆至pcDNATM6.2-GW/EmGFP-miR真核表达载体中,构建含靶向人Id3基因的miRNA表达质粒(pcDNA6.2-GW/EmGFP-miR-Id3),DNA测序验证后,采用Lipofectamine2000TM脂质体转染技术将该质粒导入A549细胞。荧光倒置显微镜下观察miRNA干扰质粒转染A549细胞后EGFP的表达情况,应用RT-PCR和Western blot方法分别检测miRNA干扰后Id3mRNA及蛋白水平的表达。结果DNA测序表明重组质粒pcDNA6.2-GW/EmGFP-miR-Id3构建正确,将其成功导入A549细胞后,在Id3mRNA水平和蛋白表达水平均有不同程度的抑制作用。结论成功构建了针对人Id3基因的4组pcDNA6.2-GW/EmGFP-miR-Id3miRNA表达载体,其中,SRId3-1干扰组在mRNA水平和蛋白表达水平均能有效抑制A549细胞Id3的表达。展开更多
基金supported by An American Brain Tumor Association Basic Research grant to G.G.G. in memory of Keith Powers, P01-CA95616, R01-NS080939James S. McDonnell Foundation
文摘Receptor tyrosine kinases(RTKs)such as the epidermal growth factor receptor(EGFR)regulate cellular homeostatic processes.EGFR activates downstream signaling cascades that promote tumor cell survival,proliferation and migration.Dysregulation of EGFR signaling as a consequence of overexpression,amplification and mutation of the EGFR gene occurs frequently in several types of cancers and many become dependent on EGFR signaling to maintain their malignant phenotypes.Consequently,concerted efforts have been mounted to develop therapeutic agents and strategies to effectively inhibit EGFR.However,limited therapeutic benefits to cancer patients have been derived from EGFR-targeted therapies.A well-documented obstacle to improved patient survival is the presence of EGFR-inhibitor resistant tumor cell variants within heterogeneous tumor cell masses.Here,we summarize the mechanisms by which tumors resist EGFR-targeted therapies and highlight the emerging role of microRNAs(miRs)as downstream effector molecules utilized by EGFR to promote tumor initiation,progression and that play a role in resistance to EGFR inhibitors.We also examine evidence supporting the utility of miRs as predictors of response to targeted therapies and novel therapeutic agents to circumvent EGFR-inhibitor resistance mechanisms.
基金supported by National Institutes of Health (NIH/NCATS) grant UH3TR00943-01 through the NIH Common Fund, Office of Strategic Coordination(OSC)the NIH/NCI grant 1 R01 CA182905-01+6 种基金a U54 grant-UPR/MDACC Partnership for Excellence in Cancer Research 2016 Pilot Projecta Team DOD (Grant No.CA160445P1) granta Ladies Leukemia League granta CLL Moonshot Flagship projecta SINF 2017 grantthe Estate of C.G.Johnson,Jr.supported by a POC grant, entitled "Clinical and economical impact of personalized targeted anti-microRNA therapies in reconverting lung cancer chemoresistance"-CANTEMIR, Competitively Operational Program, 2014-2020, Grant No.35/01.09.2016,My SMIS 103375
文摘The introduction of immune-checkpoint blockade in the cancer therapy led to a paradigm change of the management of late stage cancers. There are already multiple FDA approved checkpoint inhibitors and many other agents are undergoing phase 2 and early phase 3 clinical trials. The therapeutic indication of immune checkpoint inhibitors expanded in the last years, but still remains unclear who can benefit. Micro RNAs are small RNAs with no coding potential. By complementary pairing to the 3' untranslated region of messenger RNA, microRNAs exert posttranscriptional control of protein expression. A network of microRNAs directly and indirectly controls the expression of checkpoint receptors and several microRNAs can target multiple checkpoint molecules,mimicking the therapeutic effect of a combined immune checkpoint blockade. In this review, we will describe the microRNAs that control the expression of immune checkpoints and we will present four specific issues of the immune checkpoint therapy in cancer:(1) imprecise therapeutic indication,(2) difficult response evaluation,(3) numerous immunologic adverse-events, and(4)the absence of response to immune therapy. Finally, we propose microRNAs as possible solutions for these pitfalls. We consider that in the near future microRNAs could become important therapeutic partners of the immune checkpoint therapy.
文摘目的人分化抑制因子3(inhibitor of differentination 3,Id3)基因在A549细胞中的外源性表达能抑制细胞生长并诱导细胞凋亡。文中旨在构建靶向人Id3基因的微小分子RNA(miRNA)表达载体,观察miRNA对A549细胞中Id3表达的下调作用,为进一步探讨Id3基因在A549细胞生长调控中的作用机制提供一定实验依据。方法依据miRNA设计原则,针对人Id3基因的mRNA序列,设计并合成编码miRNA的2条寡核苷酸序列,经退火成互补双链,再克隆至pcDNATM6.2-GW/EmGFP-miR真核表达载体中,构建含靶向人Id3基因的miRNA表达质粒(pcDNA6.2-GW/EmGFP-miR-Id3),DNA测序验证后,采用Lipofectamine2000TM脂质体转染技术将该质粒导入A549细胞。荧光倒置显微镜下观察miRNA干扰质粒转染A549细胞后EGFP的表达情况,应用RT-PCR和Western blot方法分别检测miRNA干扰后Id3mRNA及蛋白水平的表达。结果DNA测序表明重组质粒pcDNA6.2-GW/EmGFP-miR-Id3构建正确,将其成功导入A549细胞后,在Id3mRNA水平和蛋白表达水平均有不同程度的抑制作用。结论成功构建了针对人Id3基因的4组pcDNA6.2-GW/EmGFP-miR-Id3miRNA表达载体,其中,SRId3-1干扰组在mRNA水平和蛋白表达水平均能有效抑制A549细胞Id3的表达。
