(G-277) Polymer and magnetic nanocarriers coating on Hedgehog Pathway inhibitor drugs for hyperthermia and targeting Hep 1-6 liver cancer cells

Introduction:: Currently, the most effective treatments for HEPATOCELLULAR carcinoma (HCC) are hepatic resection or liver transplantation. However, less than 20% of patients with HCC can be treated surgically. Furthermore, the 5-year recurrence rates of HCC after surgical resection were 57–75% due to the limited efficacy of chemotherapy, radiation and target therapy. Consequently, there is an essential requirement for the development of improved therapeutic strategies that can be used to treat HCC.

Magnetic nanoparticles (MNPs) represent a significant doorway and capacity to be magnetically manipulated by an external magnetic field. Superparamagnetic particles have already found their place within various biomedical applications such as cancer therapy [1]. On the other way, it has been known that polyethylene glycol (PEG) is both highly water soluble and not absorbed by humans, anticancer drugs, organ preservation, using on tablets, they also act as lubricants and binders, non-toxic and antibacterial, which is often employed in various medical applications [2].
We report here the coating of PEG of different concentrations (25 and 50 v/v%; represented as PEG (25) and PEG (50) respectively, in the text). In addition, we have coated two different drugs used for treating HCC (GDC-0049 and HPI-1). The present experiment suggest the succesful coating of magnetite nanoparticles synthesized via chemical and green synthesis route with PEG. The coated MNPs conjugated with drugs showed the inhibition of Hepa 1-6 cancer cells. The prepared nanocarriers are promising anti-cancer drug candidates for clinical applications.


Materials and Methods:: Chemical route- and Green route- Fe₃O₄ nanoparticles were prepared. The surface coating of Fe₃O₄ magnetic nanoparticles by PEG was achieved by mixing 25 and 50 v/v with a molecular weight of 400 g/mol with DI water for 30 minutes. Afterwards, 0.5 g of the synthesized IONPs were added into the solution and sonicated for 30 minutes for homogeneity. The solution was then transferred to an autoclave and heated up to 160 ^○C for 12h in oven. The black products were separated and washed with deionized water several times.

Results, Conclusions, and Discussions:: The measurements of the magnetic field-dependence of the magnetization of the uncoated and coated magnetite nanoparticles at room temperature are presented in Fig.1 (a) and (b). The plots indicate that all samples exhibit superparamagnetic behavior with zero remanence and coercivity. The superparamagnetic behavior is mainly generated by the magnetite cores in each sample. From Fig 1 (a), it can be observed that the bare magnetic nanoparticles exhibited 54.94 emu/g magnetization but when coating was applied it decreased to 34.19 then to 18.03 emu/g for PEG coating valued at 25 v/v and 50 v/v %. The same trend was noticeable for the green synthesized magnetic nanoparticles (Fig.1 (b)), where the bare nanoparticle also exhibited the highest magnetization at 54.74 emu/g followed by 26.85 and 5.88 emu/g by the nanoparticles coated with PEG. In general, the decrease in a magnetic moment due to coating may be explained in terms of spin pinning. Several studies have revealed that the coating thickness and hydrophobicity can drastically affects the magnetic properties of nanoparticles and decrease the M_s [3]. In this study, the magnetic nanoparticles coated with PEG coating of 25 v/v% was chosen to be conjugated with the Hh inhibitor drugs. With regards to the magnetic property and particle size were considered. Both coated magnetic nanoparticles were conjugated with drugs HPI-1and GDC-0049 having a concentration of 100 µg/mL as seen from Fig.2(a) and 2(b) respectively. From Fig.2, it can be seen that the increase in concentration of the nanoparticles with drug led to the reduced cell viability. Hence, the synthesized nanocarriers demonstrated stronger in vitro apoptosis and anti-proliferation of cancer cells, rendering them suitable for future in vivo studies. In addition, our results also suggest that upon entering the cells, both the drugs are cleaved from the conjugation, which might be due to the enzymatic reactions that occur within the cells, and tends to accumulate in the nuclei fulfilling the major requirement for an effective therapeutic system.

Acknowledgements (Optional): : This work was supported by the Ministry of Science and Technology (MOST) in Taiwan under contract no. 110-2221-E-155-019 and 111-2221-E-155 -006 -MY2.

References (Optional): : [1] R. Duncan, “The dawning era of polymer therapeutics,” Nat. Rev. Drug Discov., vol. 2, no. 5, pp. 347–360, May 2003.
[2] M. A. Al-Nasassrah, F. Podczeck, and J. M. Newton, “The effect of an increase in chain length on the mechanical properties of polyethylene glycols,” Eur. J. Pharm. Biopharm., vol. 46, no. 1, pp. 31–38, Jul. 1998.
[3] S. A. Gómez-Lopera, R. C. Plaza, and A. V. Delgado, “Synthesis and Characterization of Spherical Magnetite/Biodegradable Polymer Composite Particles,” J. Colloid Interface Sci., vol. 240, no. 1, pp. 40–47, Aug. 2001.