Gas-Mediated Cancer Bioimaging and Therapy

Abstract

Gas-involving cancer theranostics have attracted considerable attention in recent years due to their high therapeutic efficacy and biosafety. We have reviewed the recent significant advances in the development of stimuliresponsive gas releasing molecules (GRMs) and gas nanogenerators for cancer bioimaging, targeted and controlled gas therapy, and gas-sensitized synergistic therapy. We have focused on gases with known anticancer effects, such as oxygen (O 2 ), carbon monoxide (CO), nitric oxide (NO), hydrogen sulfide (H 2 S), hydrogen (H 2 ), sulfur dioxide (SO 2 ), carbon dioxide (CO 2 ), and heavy gases that act via the gas-generating process. The GRMs and gas nanogenerators for each gas have been described in terms of the stimulation method, followed by their applications in ultrasound and multimodal imaging, and finally their primary and synergistic actions with other cancer therapeutic modalities. The current challenges and future possibilities of gas therapy and imaging vis-a-vis clinical translation have also been discussed.

Four iron(II) carbonyl complexes containing both pyridyl and halide ligands: Their synthesis, characterization, stability, and anticancer activity

“…[13][14][15][16] On the other hand, CO is also believed to be of anticancer activity. [17][18][19] Therefore, exploring the medical potentials of CO have been one of the active research areas. [15][16][17][18][19][20][21] One of the actively researched areas is how safe and controllable to deliver CO. Its administration via direct inhalation is certainly the easiest and simplest approach; however, its shortcoming is obvious because of its lacking specificity and safety concern.…”

“…[17][18][19] Therefore, exploring the medical potentials of CO have been one of the active research areas. [15][16][17][18][19][20][21] One of the actively researched areas is how safe and controllable to deliver CO. Its administration via direct inhalation is certainly the easiest and simplest approach; however, its shortcoming is obvious because of its lacking specificity and safety concern. To deliver CO effectively, safely, and controllably in clinic applications, the concept of CO-releasing molecules (CORMs), either organic compounds or transition metal carbonyls, was proposed in the beginning of this century by Motterlini et al [22] The CORMs release CO under external stimulations such as ligand exchange reaction, photon-induction, redox initiation, enzymatic triggering, and thermal decomposition.…”

Emerging Delivery Strategies of Carbon Monoxide for Therapeutic Applications: from CO Gas to CO Releasing Nanomaterials

“…Take chemotherapeutic drugs for tumor treatment as an example. Chemotherapy usually suffers from drug resistance in cancer therapy, whereas gaseous CO molecules do not induce drug resistance because it can easily diffuse into the tumor tissue and lead to cell apoptosis following CO‐responsive metabolic exhaustion . Furthermore, CO could not only amplify tumor cell death when treated in combination with chemotherapeutic drugs but also exert cytoprotective function and protect normal cells against chemotherapeutic agent‐induced cell toxicity .…”

Palladium-based nanomaterials for cancer imaging and therapy

“…H 2 can selectively scavenge reactive oxygen species, especially hydroxyl radicals (•OH) and peroxynitrite anions (ONOO - ) without influence on normal metabolic oxidation/reduction reactions or cell signal transduction. In addition to tumor therapy, potential applications in anti-oxidant, anti-inflammatory, and anti-apoptotic scenarios have been studied 101 - 103 . Compared with chemotherapeutic drugs, H 2 can easily penetrate biological membranes and diffuse in tissues and cells.…”