Biomaterials Science Blog

Thyroid cancer is one of the most common endocrine malignancies, and it is the cause of more deaths than all other endocrine cancers combined. Papillary thyroid cancer, a type of thyroid cancer, is often asymptomatic, but because of the progress of modern diagnostic technology its detection rate has shown a rapid increase in the past decade. It has a lower degree of malignancy than that of other types of thyroid cancers and the tumor growth rate is slow, however, it is still very serious as it can develop throughout the thyroid gland and spread extensively in the body, even spreading to distant organs. The conventional method for treating papillary thyroid cancer is surgery, but this comes with a significant risk of injury. Hence, there is a strong need for non-invasive therapeutics which can be used as an alternative to surgery in the treatment of papillary thyroid cancer.

Recently, mitochondria-targeting nanomaterials have gained major attention as mitochondria are cells’ powerhouse, controls various signaling pathways including apoptosis and necrosis and produce reactive oxygen species (ROS). It is important to mention that increases ROS can cause the proliferation of cancer cells and drug resistance. In this present work, researchers used a mitochondria-targeted and exocytosis inhibition strategy. They used polydopamine-coated gold-silver alloy nanoparticles (Au-Ag@PDA NPs) to target papillary thyroid cancer cells (TPC-1 cells). In order to understand the nano-bio interactions between the nanoparticles and the cancer cells, the authors systematically studied the endocytosis pathway, the subcellular localization, and the cellular responses to the nanoparticles.

The results showed that:

(i)Au-Ag@PDA NPs were internalized through a caveolae-mediated and macropinocytosis pathway, localized in mitochondria and block exocytosis pathway

(ii) This lead to cell cycle arrest in S-phase and this inhibited the cell proliferation

(iii) The TPC-1 cells can survive by an autophagy-mediated method to escape the apoptosis or necrosis

The researchers, using the mitrochondria targeting behavior of the nanoparticles, then carried out photothermal therapy for the enhanced treatment of the papillary thyroid cancer cells. These findings indicate that PDA-coated inorganic nanoparticles have potential in mitrochondria-targeted cancer treatments and, one day, these could be provide an alternative to surgery for patients suffering from papillary thyroid cancer.

Read the full paper for free until the 13th May

Targeting mitochondria with Au–Ag@Polydopamine nanoparticles for papillary thyroid cancer therapy Biomater. Sci., 2019, 7, 1052-1063

About the Web/Blog writer:

Dr. Sudip Mukherjee is a Web Writer for Biomaterials Science. He is currently a Postdoctoral Research Associate at the Rice University. His research is involved in the development of advanced nanomaterials for drug/gene delivery in cancer theranostics, immunomodulatory applications & angiogenesis. He published a total of ~35 research articles/patents. He serves as International Advisory Board Member for ‘Materials Research Express‘, IOP Sciences. He is an associate member (AMRSC) of RSC, UK. He serves as reviewer for several international journals like ChemComm, J Mater Chem A, J Mater Chem B, Journal of Biomedical Nanotechnology, RSC Advances, IOP Nanotechnology, Biofabrication etc.

Contact Email: sudip.mukherjee@rice.edu
Twitter: https://twitter.com/sudip_88

Preventing or minimizing the adverse effects of anti-cancer chemotherapy has been a great challenge, due to the non-specific distribution of chemodrugs in healthy organs. Many previous works have attempted to address this issue by improving the accumulation of cytotoxic drugs in the tumor, with various targeting strategies. All the drug targeting methods enhance efficacy and reduce side-effects to a certain extent, but they cannot completely avoid the unfavourable adverse effects. Site-specific activation of chemotherapeutic drugs via a photo trigger has been a promising means of reducing side-effects.

The Zhao group at Tianjin University report the use of cyclodextrin-bearing polymer micelles for the on-demand delivery of a photoswitchable microtubule inhibitor, to achieve precision chemotherapy. The tailored inhibitor displays conformation-dependent cytotoxicity with a low potency; the “trans” isomer is thermodynamically stable and inactive, whereas the “cis” isomer is active, but thermodynamically unstable. Light irradiation activates the drug from the “trans” to “cis” form, which then instantly induces rapid drug release. Such simultaneous drug activation and release could compromise the low drug potency to a certain extent, showing improved anti-cancer efficacy in vitro and in vivo. Therefore, photo-triggered nanosystems could open new avenues of on-demand precision chemotherapy, without the risk of adverse effects on healthy organs and tissues.

This article is free to read until 30 April 18

Photo-triggered micelles: simultaneous activation and release of microtubule inhibitors for on-demand chemotherapy Biomater. Sci., 2018, 6, 511-518

About the Web/Blog writer:

Dr. Sudip Mukherjee is a Web Writer for Biomaterials Science. He is currently a Postdoctoral Research Associate at the Rice University. His research is involved in the development of advanced nanomaterials for drug/gene delivery in cancer theranostics, immunomodulatory applications & angiogenesis. He published a total of ~30 research articles/patents. He serves as International Advisory Board Member for ‘Materials Research Express‘, IOP Sciences. He is an associate member (AMRSC) of RSC, UK. He serves as reviewer for several international journals like ChemComm, J Mater Chem A, J Mater Chem B, Journal of Biomedical Nanotechnology, RSC Advances, IOP Nanotechnology etc.

Contact Email: sudip.mukherjee@rice.edu

Twitter: https://twitter.com/sudip_88

Good quality MRI contrast agents require profound tumor-targeting ability, well relaxivity, along with rapid clearance properties. In this context, endogenous biological mimicking biomaterials, with high biodegradability and biocompatibility hold enormous potential for the development of clinically translatable nanotheranostics platforms. Manganese plays a crucial role in mitochondrial and cellular function and recently, manganese (Mn)-based contrast agents have been receiving significant attention, due to improved biosafety and superior contrast abilities. However, the long term toxicity and non-biodegradability of these inorganic nanoplatforms have significantly halted their clinical progress. In contrast to this, melanin, an asymmetrical natural biopolymer, has garnered enormous attention due to good biocompatibility, biodegradability and MRI contrast imaging abilities. Hence, exploring endogenous natural materials with high contrast properties seems promising as clinically translatable in vivo MRI imaging contrast agent.

The Wang group developed an ultra small and water soluble Mn²⁺ chelating pegylated melanin nanoparticles (MNP-PEG-Mn) demonstrating excellent tumor-targeting Magnetic Resonance Imaging (MRI) ability. The MNP-PEG-Mn nanoparticles show a size of 5.6 nm displaying high chelating stability and low cytotoxicity. Interestingly, the MNP-PEG-Mn nanoparticles show improved longitudinal relaxivity compared to clinically approved MRI contrast agent Gadodiamide. In vivo studies further showcased excellent tumor targeting abilities upon intravenous administration of MNP-PEG-Mn nanoparticles in mouse model. The author further showed that the MNP-PEG-Mn nanoparticles could be excreted via hepatobiliary and renal routes. In this process negligible toxicity was generated to body tissues that indicate high biocompatibility. Altogether, these results clinically validate the tumor targeted T1 MRI contrast properties of bio-mimicking melanin conjugated manganese nanoparticles.

Melanin-manganese nanoparticles with ultrahigh efficient clearance in vivo for tumor-targeting T1 magnetic resonance imaging contrast agent . Biomater. Sci., 2018, 6, 207-215.

This article is free to read until 28 February!

About the Web writer:

Dr. Sudip Mukherjee is a Web Writer for Biomaterials Science. He is currently a Postdoctoral Research Associate working at the Department of Bioengineering at the Rice University. His research is involved in the development of advanced nanomaterials for drug/gene delivery in cancer theranostics, immunotherapy, immunomodulatory applications & angiogenesis. He published a total of ~30 research articles/patents. He serves as International Advisory Board Member for ‘Materials Research Express‘, IOP Sciences. He is an associate member (AMRSC) of The Royal Society of Chemistry, UK. He serves as reviewer for several international journals like Chem Comm, J Mater Chem A, J Mater Chem B, Journal of Biomedical Nanotechnology, RSC Advances, IOP Nanotechnology etc. He can be contacted by email at sudip.mukherjee@rice.edu or on Twitter.