低剂量化疗能更好地控制肿瘤
2016/02/27
根据本周Science Translational Medicine的报导,与其试图用强大的化疗药物去消灭癌症,不如用低剂量的药物更好地控制肿瘤。


与其试图用强大的化疗药物去消灭癌症,不如用低剂量的药物更好地控制肿瘤。

这是实施在小鼠乳腺癌的研究,根据本周Science Translational Medicine的报导,这是一个在肿瘤学研究中不断增长的趋势,以期能替代有毒副作用的高剂量化疗。

治疗癌症的标准方法是给患者最大耐受量的化疗,在不杀死病人的情况下,尽可能最大限度地损害肿瘤。这个方法是比较有效的,但也会导致毒副作用。现在Pedro Enriquez-Navas等人已经证明了一种不同的方法,即确保化疗的疗效有最大限度地减少毒性。作者用了一个进化的方法,在化疗的剂量由之前肿瘤反应的剂量指导,当肿瘤持续有反应时允许药物渐渐退出。这种方法在两个紫杉醇处理的不同模式小鼠中都很有效。


图示中深色星状细胞为对药物抗性癌细胞;深色正常细胞为对药物敏感癌细胞。

标准化肿瘤治疗如图杀死大部分药物敏感癌细胞,留下抗性癌细胞。而适应性治疗可以逐渐消灭这两种癌细胞。

作者Pedro Enriquez-Navas和他在 H. Lee Moffitt 癌症研究中心和Tampa研究所的同事说:“我们的研究结果表明,这种自适应的治疗策略可以延长乳腺癌的生存期。”

一些研究者质疑标准化疗的使用,因为它很少完全清除肿瘤,会留下耐药细胞,接下来导致肿瘤的爆炸性生长。标准剂量的紫杉醇缩小老鼠的乳腺肿瘤,但治疗结束后这些肿瘤又生长回来了。

相比之下,适应性治疗即起始是较高的剂量,其次逐步降低,这样比标准治疗更能有效地控制肿瘤生长。研究发现60-80%进行适应性治疗的小鼠停止药物后有相当一段时间没有复发。

肿瘤的磁共振成像和组织学分析表明表明适应性的治疗增加血管密度和减少坏死,表明血管正常化导致肿瘤体积的稳定,可能更有助于用低剂量药物控制肿瘤的生长。

在建议使用到人体上之前还需要更多的研究。然而这项研究提供为未来的治疗方案提供了很好的可能。越来越多的医生将从事这一版本的方法。

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