Methotrexate (MTX) by oral taking has been employed as the first‐line medication for various chronic inflammatory diseases treatment, such as Crohn's disease and rheumatoid arthritis (RA). However, the oral administration of MTX has very limited clinical benefits and will be discontinued due to the suboptimal response and severe adverse effects on intestinal mucosa. Herein, a multistage albumin nanomedicine depot (denoted as MAND) is formulated by encapsulating MTX‐loaded human serum albumin nanoparticles (MTX@HSA NPs) into calcium alginate chitosan microcapsules using a gas‐shearing technology. The MANDs can provide protection to MTX@HSA NPs with well‐persisted biologic activity against gastric acid erosion and realize specific boost release of MTX@HSA NPs in the intestinal tract in response to the mild basic circumstance. The MTX@HSA NPs absorbed by intestine can selectively accumulate in inflammation lesion by exploiting the inflammation targeting ability of HSA. In the animal experiments, the MANDs show improved therapeutic efficacy for the treatment of both RA and colitis with minimized intestinal side effects in respect to the free MTX by oral administration. Therefore, this conceived oral MANDs can promote a more clinic popularity and enhanced benefits of MTX for the treatment of chronic inflammatory diseases.

Metastasis of breast cancer is key to poor prognosis and high mortality. However, the excess reactive oxygen species (ROS) and inflammatory response induced by photothermal therapy (PTT) further aggravate tumor metastasis. Meanwhile, the hypoxic tumor microenvironment promotes tumor cells to metastasize to distant organs. Herein, the intrinsic limitations of PTT for metastatic tumor have been addressed by fabricating polyethylene glycol modified iridium tungstate (IrWO x -PEG) nanoparticles. The as-designed IrWO x -PEG nanoparticles displayed good photothermal (PT) conversion ability for duplex photoacoustic/PT imaging guided PTT and multienzyme mimetic feature for broad-spectrum ROS scavenging. On the one hand, IrWO x -PEG effectively removed excess ROS generated during PTT and reduced inflammation. On the other hand, owing to the catalase-like activity, it preferentially triggered the catalytic production of oxygen by decomposing ROS, leading to relieving of the hypoxic microenvironment. Hence, under bimodal imaging guidance, IrWO x -PEG induced PTT completely eliminated in situ breast cancer in 4T1 tumor-bearing mice with no observable system toxicity, as well as further restricting tumor metastasis to other vital organs (lungs) by ROS scavenging, anti-inflammation, and regulating hypoxic microenvironment. We anticipate that this work will lead to new treatment strategies for other metastatic cancers.

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Photothermal immunotherapy has shown great potential for efficient cancer treatment. However, the immunosuppressive tumor microenvironment forms a heavy barrier for photothermal-induced anti-tumor immunity by inhibiting dendritic cells (DCs) maturation and...