The Gurdon Institute and the Department of Genetics, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, U.K.
Essays Biochem. 2012;53:129-40. doi: 10.1042/bse0530129.
Epithelial cells are polarized along their apical-basal axis. Much of the cellular machinery that goes into establishing and maintaining epithelial cell polarity is evolutionarily conserved. Model organisms, including the fruit fly, Drosophila melanogaster, are thus particularly useful for the study of cell polarity. Work in Drosophila has identified several important components of the polarity machinery and has also established the surprising existence of a secondary cell polarity pathway required only under conditions of energetic stress. This work has important implications for the understanding of human cancer. Most cancers are epithelial in origin, and the loss of cell polarity is a critical step towards malignancy. Thus a better understanding of how polarity is established and maintained in epithelial cells will help us to understand the process of malignant transformation and may lead to improved therapies. In the present chapter we discuss the current understanding of how epithelial cell polarity is regulated and the known associations between polarity factors and cancer.
上皮细胞沿着它们的顶端-基底轴呈现极化状态。许多用于建立和维持上皮细胞极性的细胞机制在进化上是保守的。包括果蝇在内的模式生物因此特别适合用于研究细胞极性。果蝇的研究工作已经确定了极性机制的几个重要组成部分，并且还建立了一个令人惊讶的存在，即只有在能量应激条件下才需要的次要细胞极性途径。这项工作对理解人类癌症具有重要意义。大多数癌症起源于上皮细胞，而细胞极性的丧失是向恶性转化的关键步骤。因此，更好地理解上皮细胞中极性是如何建立和维持的，将有助于我们理解恶性转化的过程，并可能导致更好的治疗方法。在本章中，我们讨论了目前对上皮细胞极性如何受到调节的理解，以及极性因子与癌症之间的已知关联。
