单细胞测序法研究肿瘤异质性

对于肿瘤领域的研究工作者及临床医生来说，肿瘤异质性是一个长久以来所关注的热点问题。所谓肿瘤异质性，即是指肿瘤细胞具有不同表型和功能。目前解释肿瘤异质性机制的理论包括肿瘤进化理论（clonal evolution，CE）以及肿瘤干细胞（cancer stem cell，CSC）理论。前者强调的是肿瘤细胞具有突变的生物学特性，从而导致肿瘤的发生及发展。而后者则强调肿瘤干细胞的分化，使其发展成为具有不同功能的肿瘤细胞，稳定肿瘤的内环境。从种种迹象表明，两种理论相互共存，促进了肿瘤的发牛发展。近年来，单细胞测序（single cell sequencing，SCS）作为一种最新开展的研究方法已应用到了肿瘤异质性研究领域，并具有良好的临床应用前景。它的开展可极大程度地辅助早期小病灶肿瘤的发现、循环肿瘤细胞（circulating tumour cells，CTCs）的监测以及晚期肿瘤药物耐药的判断，从而提高肿瘤的早期诊断、个体化治疗的效果以及预后等方面。

Investigating intratumour heterogeneity by single-cell sequencing

Intratumour heterogeneity is a longstanding field of focus for both researchers and clinicians. It refers to the diversity amongst cells within the same tumour. Two major hypotheses have attempted to explain the existence of intratumour heterogeneity： （i） the clonal evolution （CE） theory and （ii） the cancer stem cell （CSC） model. CE theory emphasizes the evolutionary biological characteristics of the tumour, underscoring the initiation and progression of the disease. In contrast, the CSC model focuses on stem cell differentiation into distinct functions in order to stabilize the tumour microenvironment. Here we consider single-cell sequencing （SCS） as a newly developed technique for application to the investigation of intratumour heterogeneity and assess its relevance within research and clinical environments. Early detection of rare tumour cells, monitoring of circulating tumour cells （CTCs） and control of the occurrence of drug resistance are imoortant goals in early diagnosis, prognosis prediction and individualized medicine.