Doxorubicin·Hydrochloride/Cisplatin-Loaded Hydrogel/Nanosized (2-Hydroxypropyl)-Beta-Cyclodextrin Local Drug-Delivery System for Osteosarcoma Treatment In Vivo

Abstract

Osteosarcoma (OSA) is a difficult cancer to treat due to its tendency for relapse and metastasis; advanced methods are therefore required for OSA treatment. In this study, we prepared a local drug-delivery system for OSA treatment based on doxorubicin·hydrochloride (DOX·HCl)/cisplatin (CP)-loaded visible light-cured glycol chitosan (GC) hydrogel/(2-hydroxypropyl)-beta-cyclodextrin (GDHCP), and compared its therapeutic efficiency with that of DOX·HCl- and CP-loaded GC hydrogels (GD and GHCP). Because of diffusion driven by concentration gradients in the swollen matrix, the three hydrogels showed sustained releases of DOX·HCl and CP over 7 days, along with initial 3-h bursts. Results of in vitro cell viability and in vivo animal testing revealed that GDHCP had a stronger anticancer effect than GD and GHCP even though there were no significant differences. Body weight measurement and histological evaluations demonstrated that the drug-loaded GC hydrogels had biocompatibility without cardiotoxicity or nephrotoxicity. These results suggested that GDHCP could be a good platform as a local drug-delivery system for clinical use in OSA treatment.

Keywords: (2-hydroxypropyl)-beta-cyclodextrin; cardiotoxicity; cisplatin; doxorubicin·hydrochloride; local drug delivery system; nephrotoxicity; osteosarcoma; visible light-cured glycol chitosan hydrogel.

Figure 1

Swelling ratios of cured glycol chitosan (GC) hydrogel, DOX·HCl-loaded GC hydrogel (GD), CP-loaded GC hydrogel (GHCP) and GDHCP measured at day 0, 1, 2, 3, 4, 5, 6, 7, 14, 21, and 28 days. At the determined intervals, the hydrogels immersed in PBS (pH 7.4) at 37 °C were extracted, dried and weighted. This experiment was performed three times.

Figure 2

Cumulative release percentages of DOX·HCl and/or CP in GD, GHCP and GDHCP measured at day 1, 3, 6, 12, 24, 48, 72, 96, 120, 144, and 168 h. This experiment was performed three times in PBS (pH 7.4) at 37 °C.

Figure 3

Proliferation rates of (top) MG-63 and (down) KHOS/NP cells cultured with control, GD, GHCP and GDHCP (DOX·HCl: 2 mg/kg and CP: 2 mg/kg against each hydrogel) at 37 °C for 1, 3, 5 and 7 days under 5% CO₂ conditions. Practical treated amounts of DOX·HCl and CP were 50 ng because the average body weight was 25 mg. This experiment was performed three times (* p < 0.05). The significance was compared with the control.

Figure 4

(Top) Gross appearances of cancer bearing to the femoral lesion of control, GC, GD, GHCP and GDHCP observed at 4 weeks after intratumoral injection. The injection was performed once a week for 4 weeks. (Bottom) Cancer volumes in control, GC-, GD-, GHCP- and GDHCP-treated mice (# p < 0.05). The significance was compared with the control.

Figure 5

Body weights of control, GC-, GD-, GHCP- and GDHCP-treated mice measured at 1, 2, 3 and 4 weeks. This experiment was performed three times (* p < 0.05). The significance was compared with the control.

Figure 6

H&E stained slides of cancer tissues extracted from control, cancer bearing, GD-, GHCP- and GDHCP-treated mice after 4 weeks. The slides were observed at 20×. The scale bars indicate 100 µm. The yellow dotted lines indicated necrotic area.

Figure 7

H&E stained slides of heart tissues extracted from control, cancer bearing, GD- and GDHCP-treated mice after 4 weeks. The slides were observed at 4×. The scale bars indicate 500 µm.

Figure 8

H&E stained slides of heart tissues extracted from control, cancer bearing, GHCP- and GDHCP-treated mice after 4 weeks. The slides were observed at 20×. The scale bars indicate 100 µm.

Figure 9

In vivo anticancer effect of GDHCP hydrogel on osteosarcoma. The hydrogel was locally injected into the cancer tissue once a week for 4 weeks.