Liu J H, Stass S A, Chang K S
Division of Laboratory Medicine, University of Texas M. D. Anderson Cancer Center, Houston 77030.
Leuk Lymphoma. 1994 May;13(5-6):381-6. doi: 10.3109/10428199409049626.
Annexin VIII is preferentially expressed in APL, but its level of expression in other subtypes of AML is much lower. Annexin VIII was originally found to be a vascular anticoagulant, but evidence obtained from our recent studies suggests that it does not play a role in hemorrhage diathesis in APL. The specific expression of annexin VIII in APL may relate to its possible role in hematopoietic cell differentiation. The expression of annexin VIII is developmentally regulated in APL-derived NB4 cells. It can be downregulated as a response to induction by ATRA, an agent which is also capable of inducing maturation of NB4 cells. Our current understanding is that annexin VIII is most likely involved in signal transduction and may have a role as a modulator of PKC. A change in cellular PKC activity is expected to have a significant impact on cell differentiation and proliferation. The biological function of annexin VIII is currently unknown, but its expression in APL and its possible role in differentiation and proliferation of the leukemia cells would provide an excellent model system to study and elucidate this intriguing question.
膜联蛋白VIII在急性早幼粒细胞白血病（APL）中优先表达，但其在急性髓系白血病（AML）其他亚型中的表达水平要低得多。膜联蛋白VIII最初被发现是一种血管抗凝剂，但我们最近的研究证据表明它在APL的出血素质中不起作用。膜联蛋白VIII在APL中的特异性表达可能与其在造血细胞分化中的潜在作用有关。膜联蛋白VIII在APL来源的NB4细胞中的表达受发育调控。它可作为对全反式维甲酸（ATRA）诱导的反应而下调，ATRA也是一种能够诱导NB4细胞成熟的药物。我们目前的认识是，膜联蛋白VIII很可能参与信号转导，并且可能作为蛋白激酶C（PKC）的调节剂发挥作用。细胞PKC活性的变化预计会对细胞分化和增殖产生重大影响。膜联蛋白VIII的生物学功能目前尚不清楚，但其在APL中的表达及其在白血病细胞分化和增殖中的潜在作用将为研究和阐明这个有趣的问题提供一个极好的模型系统。
