Nanomedicine is a rapidly growing field that uses nanomaterials for the diagnosis, treatment and prevention of various diseases, including cancer. Various biocompatible nanoplatforms with diversified capabilities for tumor targeting, imaging, and therapy have materialized to yield individualized therapy. However, due to their unique properties brought about by their small size, safety concerns have emerged as their physicochemical properties can lead to altered pharmacokinetics, with the potential to cross biological barriers. In addition, the intrinsic toxicity of some of the inorganic materials (i.e., heavy metals) and their ability to accumulate and persist in the human body has been a challenge to their translation. Successful clinical translation of these nanoparticles is heavily dependent on their stability, circulation time, access and bioavailability to disease sites, and their safety profile. This review covers preclinical and clinical inorganic-nanoparticle based nanomaterial utilized for cancer imaging and therapeutics. A special emphasis is put on the rational design to develop non-toxic/safe inorganic nanoparticle constructs to increase their viability as translatable nanomedicine for cancer therapies.

Irreversible electroporation (IRE) is an emerging minimally invasive tumor ablation technique that delivers short pulses of strong electric fields and kills cancer cells by disrupting their cell membranes with the electric pulses. However, clinical studies report that more than 10% of local tumor recurrences occur at the original ablated site. NVP BEZ-235 (BEZ) is a dual PI3K/mTOR inhibitor that has substantial anticancer effects. However, the clinical trials of BEZ was not satisfactory because of its low bioavailability and high toxicity, which stemmed from the use of oral administration of high doses over a long period of time. In this research, we prepared a liposomal formulation of BEZ (L-BEZ) for intratumoral injection and studied its antitumor efficacy alone and in combination with IRE. We hypothesized that IRE could release BEZ from the liposomes and that the combination could decrease tumor viability. Our results show that IRE released BEZ from its liposomal encapsulation. The combination of L-BEZ and IRE killed more Hep3B tumor cells in vitro than did L-BEZ or IRE alone and also inhibited cancer cell proliferation in nude mice bearing Hep3B xenografts. Combination of chemotherapeutic agent loaded nanoparticles could enhance the antitumor efficacy of IRE.

An emerging concept is that cancers strongly depend on both internal and external signals for growth and invasion. In this review, we will discuss pathological and physical changes in the tumor microenvironment and how these changes can be exploited to design gold nanoparticles for cancer diagnosis and therapy. These intrinsic changes include extracellular and intracellular pH, extracellular matrix enzymes, and glutathione concentration. External stimuli include the application of laser, ultrasound and X-ray. The biology behind these changes and the chemistry behind the responding mechanisms to these changes are reviewed. Examples of recent in vitro and in vivo studies are also presented, and the clinical implications of these findings are discussed.

An emerging concept is that cancers strongly depend on both internal and external signals for growth and invasion. In this review, we will discuss pathological and physical changes in the tumor microenvironment and how these changes can be exploited to design gold nanoparticles for cancer diagnosis and therapy. These intrinsic changes include extracellular and intracellular pH, extracellular matrix enzymes, and glutathione concentration. External stimuli include the application of laser, ultrasound and X-ray. The biology behind these changes and the chemistry behind the responding mechanisms to these changes are reviewed. Examples of recent in vitro and in vivo studies are also presented, and the clinical implications of these findings are discussed.