Physiological parameters in tumor microenvironments, including hypoxia, low extracellular pH, enzymes, reducing conditions, and so on, are closely associated with the proliferation, angiogenesis, invasion, and metastasis of cancer, and impact the therapeutic administrations. Therefore, monitoring the tumor microenvironment is significant for diagnosing tumors, predicting the invasion potential, evaluating therapeutic efficacy, planning the treatment, and cancer prognostics. Noninvasive molecular imaging technologies combined with novel “smart” nanoparticle‐based activatable probes provide a feasible approach to visualize tumor‐associated microenvironment factors. This review summarizes recent achievements in the designs of “smart” molecular imaging nanoprobes responding to the tumor microenvironment–related features, and highlights the state of the art in tumor heterogeneity imaging.

中文翻译：

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用于可视化肿瘤微环境的“智能”纳米探针

肿瘤微环境中的生理参数，包括低氧，低细胞外pH，酶，还原条件等，与癌症的增殖，血管生成，侵袭和转移密切相关，并影响治疗管理。因此，监测肿瘤的微环境对于诊断肿瘤，预测侵袭潜能，评估治疗效果，计划治疗和癌症预后具有重要意义。非侵入性分子成像技术与新型的基于纳米的“智能”可激活探针相结合，为可视化肿瘤相关的微环境因素提供了一种可行的方法。这篇综述总结了响应于肿瘤微环境相关特征的“智能”分子成像纳米探针设计的最新成果，