Development and characterization of a scalable microperforated device capable of long-term zero order drug release

Correlation between miR-23a and onset of hepatocellular carcinoma

BACKGROUND AND AIMS

To clarify the role of miR-23a in the onset and development of hepatocarcinoma on the cellular, genetic and molecular levels.

PATIENTS AND METHODS

Seventy-eight patients were included after hepatectomy. Relationships between the clinical pathological factors of tumor and paracancerous tissues were analyzed. Risk factors of overall and recurrence-free survival rates were subject to multi-variable analysis. Tissues were sequenced by digital miRNA expression profiling, and new miRNA was subject to target gene prediction.

RESULTS

miR-23a expression was correlated with the stage of the TNM Classification of Malignant Tumours most significantly, followed by tumor size (P=0.041 and 0.047). High miR-23a, vascular invasion, tumor size≥7cm, tumor capsule and late pathological stage were the risk factors of overall survival rate, and those of recurrence-free survival rate also included alpha-fetoprotein level≥200μg/L and multiple tumors. Compared with normal hepatic cell line L-02, the miR-23a expression levels in tumor cell lines SMMC-7721 and HepG2 were up-regulated and down-regulated respectively. Transfecting miR-23a inhibitor suppressed cell growth. Apoptotic rates of the control and those transfected with inhibitor-NC and miR-23a inhibitor for 48h were similar.

CONCLUSION

High miR-23a expression is the independent prognostic factor of overall and recurrence-free survival rates, and miR-23a may be involved in the onset of hepatocarcinoma as an oncogene.

Evaluation of a perforated drug delivery system in mice for prolonged and constant release of a hydrophilic drug

A drug delivery system (DDS) consisting of a perforated microtube (polyimide, inside diameter = 1.8 mm, tube length = 20 mm, hole size = 0.15 mm) was characterized in vitro and in vivo for its usefulness for long-term release of hydrophilic drugs at a constant rate. Sodium fluorescein mixed with stearic acid was used as the model drug. The DDS was packed with sodium fluorescein and stearic acid in ratios of 50:50, 40:60, and 25:75, respectively, and in vitro drug release studies were performed in saline. Linear release rates with R (2) > 0.9700 were obtained for all groups. Release rates of 1,077.3 ± 264.6, 342.6 ± 146.4, and 14.4 ± 7.0 μg/day for sodium fluorescein were obtained from the three groups, respectively. After monitoring the in vitro release of fluorescein for 11 days, 7 tubes from the 40:60 group were implanted subcutaneously in each individual mice to study the in vivo release of fluorescein from the tubes by measuring the fluorescein in the urine for 84 days. An initial rapid release during the first 4 days was followed by a near zero order fluorescence from the tubes (R (2) = 0.9870). Following completion of the study, the DDSs were retrieved for histology. Morphological analysis indicated no clinical adverse reaction at the site of device implantation specific to the device. The DDS was found to be biocompatible and capable of long-term constant release of a hydrophilic drug such as sodium fluorescein.