Hydroxyapatite Nanoparticles for Improved Cancer Theranostics

Abstract

Beyond their well-known applications in bone tissue engineering, hydroxyapatite nanoparticles (HAp NPs) have also been showing great promise for improved cancer therapy. The chemical structure of HAp NPs offers excellent possibilities for loading and delivering a broad range of anticancer drugs in a sustained, prolonged, and targeted manner and thus eliciting lower complications than conventional chemotherapeutic strategies. The incorporation of specific therapeutic elements into the basic composition of HAp NPs is another approach, alone or synergistically with drug release, to provide advanced anticancer effects such as the capability to inhibit the growth and metastasis of cancer cells through activating specific cell signaling pathways. HAp NPs can be easily converted to smart anticancer agents by applying different surface modification treatments to facilitate the targeting and killing of cancer cells without significant adverse effects on normal healthy cells. The applications in cancer diagnosis for magnetic and nuclear in vivo imaging are also promising as the detection of solid tumor cells is now achievable by utilizing superparamagnetic HAp NPs. The ongoing research emphasizes the use of HAp NPs in fabricating three-dimensional scaffolds for the treatment of cancerous tissues or organs, promoting the regeneration of healthy tissue after cancer detection and removal. This review provides a summary of HAp NP applications in cancer theranostics, highlighting the current limitations and the challenges ahead for this field to open new avenues for research.

Review targeted drug delivery systems for norcantharidin in cancer therapy

“…Hydroxyapatite can deliver antitumor drugs, and its composite material hydroxyapatite/CS can repair bone defects [ 81 , 82 ]. Strontium (Sr), a trace element in the human body, has been found to have the ability to promote bone formation and inhibit osteoclasts, which have positive effects on improving the osteogenic activity of the composite [ 83 ].…”

Antioxidant Effects of Bioactive Glasses (BGs) and Their Significance in Tissue Engineering Strategies

“…Oxidative stress is described as the imbalance of redox homeostasis due to an irregular increase in free radicals and other reactive molecules, which in healthy conditions play a natural role in cell signaling [ 22 ]. In fact, a short-term and relatively small rise in ROS is required for the redox signaling in biological processes such as angiogenesis (HIF-regulated) or inflammation (NADPH oxidases), while a long-term and relatively large increase in ROS induces damage to vital cellular macromolecules, DNA, proteins, or lipids [ 23 , 24 ]. Free radicals (e.g., ROS) or pro-oxidant molecules (compounds that induce oxidative stress) have one or more unpaired electrons that make them extremely reactive for taking electrons from other molecules.…”

Hydroxyapatite Biobased Materials for Treatment and Diagnosis of Cancer

“…This structure is constituted by Ca 2+ ions surrounded by tetrahedral PO 4 3− units and OH − ions, occupying columns that are parallel to the hexagonal axis. Ca 2+ ions are mainly disposed at the c -surface and the PO 4 3− and OH − ions are located on the a -surface [ 44 ].…”

“…A great diversity of methods have been applied for HAp synthesis. They can be classified into (i) dry methods (e.g., solid state or mechanical route), (ii) wet methods (chemical precipitation, sol-gel, hydrothermal, emulsion and sonochemical routes), (iii) high-temperature processes (pyrolysis methods), (iv) methods based on biogenic sources, and (v) combinations of techniques [ 44 , 45 , 46 , 47 ].…”