Single cell transcriptome (SCT) analysis provides superior resolution to illustrate tumor cell heterogeneity for clinical implications. We characterized four SCTs of MCF-7 using 143 housekeeping genes (HKGs) as control, of which lactate dehydrogenase B (LDHB) expression is silenced. These SCT libraries mapped to 11,423, 11,486, 10,380, and 11,306 RefSeq genes (UCSC), respectively. High consistency in HKG expression levels across all four SCTs, along with transcriptional silencing of LDHB, was observed, suggesting a high sensitivity and reproducibility of the SCT analysis. Cross-library comparison on expression levels by scatter plotting revealed a linear correlation and an 83–94% overlap in transcript isoforms and expressed genes were also observed. To gain insight of transcriptional diversity among the SCTs, expressed genes were split into consistently expressed (CE) (expressed in all SCTs) and inconsistently expressed (IE) (expressed in some but not all SCTs) genes for further characterization, along with the 142 expressed HKGs as a reference. Distinct transcriptional strengths were found among these groups, with averages of 1,612.0, 88.0 and 1.2 FPKM for HKGs, CE and IE, respectively. Comparison between CE and IE groups further indicated that expressions of CE genes vary more significantly than that of IE genes. Gene Ontology analysis indicated that proteins encoded by CE genes are mainly involved in fundamental intracellular activities, while proteins encoded by IE genes are mainly for extracellular activities, especially acting as receptors or ion channels. The diversified gene expressions, especially for those encoded by IE genes, may contribute to cancer drug resistance.

单细胞转录组（SCT）分析可提供出色的分辨率，以说明肿瘤细胞异质性的临床意义。我们使用143个管家基因（HKGs）作为对照，对MCF-7的四个SCT进行了表征，其中乳酸脱氢酶B（LDHB）的表达被沉默。这些SCT库分别映射到11,423、11,486、10,380和11,306 RefSeq基因（UCSC）。所有四个SCT的HKG表达水平高度一致，并且LDHB转录沉默观察到，表明SCT分析具有很高的灵敏度和可重复性。通过散点图对表达水平进行跨库比较，结果显示出线性相关性，并且在转录亚型和表达基因之间存在83-94％的重叠。为了深入了解SCT之间的转录多样性，将表达的基因分为142个一致表达（CE）（在所有SCT中都有表达）和不一致表达（IE）（在某些但不是全部SCT中都有表达）的基因，以便进行进一步表征。以HKGs为参考。在这些组中发现不同的转录强度，HKG，CE和IE的平均值分别为1,612.0、88.0和1.2 FPKM。CE和IE组之间的比较进一步表明，CE基因的表达比IE基因的表达差异更大。基因本体分析表明，CE基因编码的蛋白质主要参与细胞内的基本活动，而IE基因编码的蛋白质主要参与细胞外的活动，尤其是作为受体或离子通道。多样化的基因表达，尤其是由IE基因编码的基因表达，可能有助于癌症的耐药性。