The effects of chemotherapy on the tumor microenvironment remain poorly investigated, although these are crucial for the drug delivery and anti-tumor activity and can modify physiological behavior of cancer cells. Optical coherence angiography and phosphorescence lifetime spectroscopy are promising optical methods to characterize both tumor vasculature and its oxygenation, respectively. In this study, we used these methods to explore the influence of irinotecan, a widely used chemotherapeutic agent, on tumor angiogenesis and oxygen content in a mouse model of colorectal cancer in vivo. For the first time, it was shown that irinotecan at conventional dosing reduces tumor oxygenation and blood perfusion via antiangiogenic mechanism of action. Immunohistochemistry for hypoxia and for the endothelial cell marker CD31 verified the in vivo findings. These data show the prospects of the optical techniques to monitor tumor microenvironment in the course of chemotherapy, which can help to optimize and individualize the treatment.

中文翻译：

---

伊立替康对肿瘤血管系统和氧合的影响：对结直肠癌模型的体内研究

化疗对肿瘤微环境的影响仍然缺乏研究，尽管这些对药物递送和抗肿瘤活性至关重要，并且可以改变癌细胞的生理行为。光学相干血管造影术和磷光寿命光谱学是分别表征肿瘤血管系统及其氧合的有前途的光学方法。在这项研究中，我们使用这些方法来探索伊立替康（一种广泛使用的化学治疗剂）对 体内 结直肠癌小鼠模型中肿瘤血管生成和氧含量的影响。首次表明，常规给药的伊立替康通过抗血管生成作用机制降低肿瘤氧合和血液灌注。缺氧和内皮细胞标记物 CD31 的免疫组织化学证实了体内发现。