Nanomaterials for cancer therapy: current progress and perspectives

Abstract

Cancer is a disease with complex pathological process. Current chemotherapy faces problems such as lack of specificity, cytotoxicity, induction of multi-drug resistance and stem-like cells growth. Nanomaterials are materials in the nanorange 1-100 nm which possess unique optical, magnetic, and electrical properties. Nanomaterials used in cancer therapy can be classified into several main categories. Targeting cancer cells, tumor microenvironment, and immune system, these nanomaterials have been modified for a wide range of cancer therapies to overcome toxicity and lack of specificity, enhance drug capacity as well as bioavailability. Although the number of studies has been increasing, the number of approved nano-drugs has not increased much over the years. To better improve clinical translation, further research is needed for targeted drug delivery by nano-carriers to reduce toxicity, enhance permeability and retention effects, and minimize the shielding effect of protein corona. This review summarizes novel nanomaterials fabricated in research and clinical use, discusses current limitations and obstacles that hinder the translation from research to clinical use, and provides suggestions for more efficient adoption of nanomaterials in cancer therapy.

Keywords: Blood–brain barrier; Cancer therapy; Drug delivery; Exosome; Nanomaterial; Protein corona; Tumor microenvironment.

Fig. 1

Categories of nanomaterials applied in cancer treatment. a Nanoparticles. b Liposomes. c Solid lipid nanoparticles. d Nanostructured lipid carriers. e Nanoemulsions. f Dendrimers. g Graphene. h Metallic nanoparticles. PEG, poly(ethylene glycol)

Fig. 2

Schematic illustration of nanomaterial involved PTT, CDT, PDT. With NIR irradiation, PTT materials such as GO/rGO generate heat and cause cancer cell death. CDT material BSA-CuFeS₂ and specific wavelength light irradiated PDT material CNTs generate ·OH, ¹O₂, O₂ − · from O₂, H₂O₂ in cells and cause cancer cell death. CDT, chemodynamic therapy; CNT: carbon nanotube; GO: graphene oxide; NIR: near-infrared; PDT: photodynamic therapy; PTT, photothermal therapy; rGO: reduced graphene oxide

Fig. 3

Illustration of interaction between nanomaterials and tumor cells. a Antigen–antibody conjugation modified nanoparticle endocytosis and transcytosis; b Liposome reaches cancerous area from blood vessels through EPR effect. c The magnetic nanoparticle coated with chitosan carries 5-Fluorouracil. Under external magnetic field, the nanoparticle shows passive targeting ability at cancer cells. d Therapeutic AuNP is blocked by BBB under normal status. After FUS exposure, the BBB is opened temporarily by microbubble inertial or stable cavitation and allows AuNPs to get through. BBB: blood–brain barrier; EPR: enhanced permeability and retention; FUS: focused ultrasound

Fig. 4

Cancer treatment approaches based on nanomaterials. a Targeting cancer cells by passive targeting or active targeting. b Targeting TME including anti-angiogenesis, stromal cell and extracellular matrix. Bevacizumab was loaded in liposome and conjugated with VEGF to inhibit angiogenesis. HAase was modified onto NP surface and enhanced NP penetration ability. c IFN-γ as an immune modulator delivered by liposomes activated immune cells in cancer immunotherapy. HAase: hyaluronidase; IFN-γ: Cytokine Interferon gamma; NP: nanoparticle; TME: tumor microenvironment; VEGF: vascular endothelial growth factor