近年來發現一氧化碳 (CO) 藉由抑制癌細胞中粒線體呼吸鏈的細胞色素 c 氧化酶，使活性氧物質 (Reactive oxygen species, ROS) 增生影響粒線體功能，透過迅速補充癌細胞的生物能誘導 anti-Warburg 效應，導致代謝衰竭促使細胞走向凋亡，因此經常用於癌症治療。鈣離子 (Ca2+) 在細胞訊號傳遞鏈中扮演重要的角色，因此鈣離子濃度的失衡會使細胞鈣化走向死亡。在本篇，我們利用具有良好生物相容性之介孔洞二氧化矽奈米粒子 (mSiO2) 裝載過氧化鈣 (CaO2) 及五羰基鐵 (Fe(CO)5)，在腫瘤酸性環境中，CaO2 可與細胞中之水分子 (H2O) 反應，產生 Ca2+ 使癌細胞中鈣離子濃度失衡以及雙氧水 (H2O2) 使 Fe(CO)5 分解產生 CO 進行 CO 治療。

Recently, carbon monoxide (CO) has been found to induce anti-Warburg effect via rapidly fueling cancer cell bioenergetics, leading to metabolic exhaustion and is therefore being extensively used for cancer therapy. Iron pentacarbonyl (Fe(CO)5) can be a CO donor upon reaction with the hydrogen peroxide (H2O2). Calcium peroxide (CaO2) dissolves in water to produce H2O2, and releases Ca2+ under acidic conditions. Calcium ions (Ca2+) play an important role in cell signal transmission; however, in tumor cell the calcium overload would lead to calcification owing to low expression of catalase (CAT) and induce cell death. In this study, mesoporous silica nanospheres are employed to carry both CaO2 and Fe(CO)5 into the acidic tumor environment to demonstrate self-generated H2O2 for simultaneous CO therapy and calcification induced tumor cell death.

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