Together,细胞生长速率和基因表达揭示了为什么一些肿瘤细胞能在治疗中存活。
Bio

By studying both the physical and genomic 188bet亚洲体育features of cancer cells,麻省理工学院的研究人员想出了一种新的方法来研究为什么有些癌细胞在药物治疗中存活,而另一些则死亡。

他们的新方法,which combines measurements of cell mass and growth rate with analysis of a cell's gene expression,可以用来揭示新的药物靶点,使癌症治疗更有效。

利用这些目标有助于摧毁细胞用来克服原始药物治疗的防御,研究人员说。

在最近一期《基因组生物学》杂志上发表的一篇论文中,the researchers identified a growth signalling pathway that is active in glioblastoma cells that are resistant to an experimental type of drug known as an MDM2 inhibitor.

“通过在单细胞RNA测序前测量细胞的质量和生长速度,we can now use a cell's ‘fitness' to classify it as responsive or non-responsive to a drug,and to relate this to underlying molecular pathways,“says Alex K Shalek,the Pfizer-Laubach Career Development Assistant Professor of 188betsportChemistry,a member of MIT's Institute for Medical Engineering and Science (IMES),科赫癌症综合研究所的校外成员,以及Ragon和Broad研究所的一名助理成员。

Shalek and Scott Manalis,麻省理工学院生物工程和机械工程系的Andrew和Erna Viterbi教授,科赫研究所成员,是这项研究的资深作者。论文的主要作者是罗伯特·金默林,最近获得麻省理工学院博士学位。

癌细胞分析


About a decade ago,Manalis' lab invented a technology that allows researchers to measure the mass of single cells.

In recent years,他们已经调整了设备,当细胞流过微小的通道时测量其质量,so that it can also measure cell growth rates by repeatedly weighing the cells over short periods of time.

Last year,working with researchers at Dana-Farber Cancer Institute (DFCI),马纳利斯和他的同事used this approach为了检测多发性骨髓瘤患者肿瘤细胞的药物反应,a type of blood cancer.

After treating the cells with three different drugs,the researchers measured the cells' growth rates and found they were correlated with the cells' susceptibility to the treatment.

药物反应早期指标


“单细胞生物物理特性,如质量和生长速率,提供药物反应的早期指标。thereby offering the potential to delineate sensitive cells from resistant cells while they are still viable,“Manalis说。

在他们的新研究中,研究人员想添加一种基因组成分,which they hoped could help reveal why only certain cells are susceptible to a particular drug.

“我们希望能够进行这些测量,并添加一些生物学背景,解释为什么一个细胞以某种方式生长或表现出某种方式,“金默林说。

To accomplish this,Kimmerling和Manalis与Shalek合作,whohas extensive experience对单个细胞的信使RNA(mRNA)进行测序。This information can provide a snapshot of which genes are being expressed in a single cell at a particular moment.

The researchers modified the cell-weighing system so that cells would be spaced evenly as they flowed through,使它们在退出系统时更容易一次收集一个。

在20分钟的过程中,对细胞进行多次称重,以确定生长速度,一旦他们到达海峡的尽头,它们被立即捕获并破裂,释放出RNA进行分析。

Shalek's lab then sequenced the RNA of each of the cells.This approach enabled the mass and growth rate of each cell to be directly linked to its gene expression.

Once they had the system working,研究人员与Keith Ligon和他在DFCI的实验室合作,分析了一名胶质母细胞瘤患者的癌细胞。an aggressive type of brain cancer.

研究人员用MDM2抑制剂处理这些细胞,一种有助于促进p53功能的药物,一种帮助细胞阻止肿瘤形成的蛋白质。

Such drugs are now in clinical trials to treat glioblastoma.In animal studies,这种药对肿瘤有效,但是肿瘤往往会在以后复发。

在这项研究中,the researchers hoped to find out why some glioblastoma cells survive MDM2 treatment.他们处理细胞,measured their growth rates about 16 hours after the treatment,然后对它们的RNA进行测序。

药物反应对治疗的异质性


“在细胞失去活性之前,我们可以测量它们的质量和生长速度,以揭示对该治疗的药物反应异质性,然后将其与基因表达联系起来,“金默林说。

重要的是,the researchers found subpopulations of cells that were not responsive to the drug.RNA sequencing revealed that in cells that were responsive,genes required for programmed cell death were turned on.

Meanwhile,in cells that did not seem to be vulnerable to the drug,genes involved in mTOR,参与生长和存活的信号通路,were turned up.

“What we're excited about here is we now have this list of biological targets to look into,“金默林说。“We can start to generate testable hypotheses from these gene expression signatures that are more highly expressed in the cells that continue to grow after drug treatment."“

可能的药物目标


研究人员现在计划探索针对一些在无反应细胞上出现的基因的可能性,in hopes of developing drugs that could be used together with the original MDM2 inhibitor.

他们还希望将这种方法应用于其他类型的癌症。一些,比如血液癌,比实体瘤更容易研究,更难分离成单个细胞。

“The hope is that we'll be able to apply this technology to any sample that can be dissociated into a single-cell population,“金默林说。

细胞生长测量技术的另一个可能应用是研究个体患者的肿瘤细胞,试图预测他们对特定药物的反应。

克默林Manalis,其他人成立了一家名为Travera的公司,which has licensed the technology and hopes to develop it for patient use.

该公司目前不在该技术的RNA测序方面工作,但这一要素在未来也可能是有价值的,金默林说。

//www.bjgzb.com/wp-content/uploads/2018/12/a-aaaaabaa1.jpg//www.bjgzb.com/wp-content/uploads/2018/12/a-aaaaabaa1-300x300.jpg戴维奥里奥登Biobiomedical,cancer,MIT
By studying both the physical and genomic 188bet亚洲体育features of cancer cells,MIT researchers have come up with a new way to investigate why some cancer cells survive drug treatment while others succumb.Their new approach,which combines measurements of cell mass and growth rate with analysis of a cell's gene...