ABSTRACT
BACKGROUND:Gemcitabine hydrochloride is a water-soluble anticancer drug that induces apoptosis in tumor cells, but it has an excessive release in vivo. OBJECTIVE:To evaluate the effect of poly(lactic acid) (PLA) electrospun fiber membranes carrying gemcitabine hydrochloride on the growth of human osteosarcoma cell lines MG-63. METHODS:PLA electrospun fiber members with (experimental) or without (control) gemcitabine hydrochloride were fabricated and characterized. Two kinds of fiber membranes were immersed in low-glucose DMEM medium, and the supernatants were collected in the two groups at 3, 5, 7 days, respectively. Passage 5 human osteosarcoma cell lines MG-63 were inoculated into 96-well plates containing low-glucose DEME with 15％ fetal bovine serum, and divided into seven groups. Groups 1-3 were cultured in the experimental supernatants of 3, 5, 7 culture days, and groups 4-6 were cultured in the control supernatants of 3, 5, 7 culture days, respectively. The remaining group acted as the negative control with no supernatant. Thereafter, cell counting kit-8 was used to detect cell proliferation, and RT-PCR was used to measure expression of Bcl-2 and Bax at 3 days of culture. RESULTS AND CONCLUSION:(1) No obvious particle was found on the smooth and even surface of the fiber members in the experimental and control groups. There was no significant difference in fiber diameter, contact angle and tensile strength between the two kinds of fiber membranes. (2) The results of cell counting kit-8 showed that compared with the negative control group, the supernatant released from the control group had no effect on the MG-63 proliferation at different time points, while the supernatant released from the experimental group could inhibit the MG-63 proliferation at different time points (P<0.05), and the inhibitory effect became more and more obvious with the prolongation of release time. (3) RT-PCR findings showed that compared with the control group, the supernatant released from the experimental group could increase Bax mRNA expression and decrease Bcl-2 mRNA expression at the same time point. To conclude, the PLA electrospun fiber membranes carrying gemcitabine hydrochloride can sustainably inhibit MG-63 proliferation and promote cell apoptosis.
ABSTRACT
BACKGROUND:Studies have shown that bioactive molecules or polypeptides grafted onto the surface of polyethylene glycol (PEG) hydrogels can improve PEG bioactivities.OBJECTIVE:To manufacture PEG hydrogels capable of auto-recruiting growth factor beta1 (TGF-β1) and to study its biocompatibility. METHODS:Pure PEG hydrogels (group A), PEG hydrogels grafted on a cell adhesion peptide RGD peptides (group B), PEG hydrogels grafted with auto-recruited TGF-β1 peptide sensitive polypeptide HSNGLPL (group C), PEG hydrogels grafted with both RGD and HSNGLPL polypeptides (group D) were prepared. Contract angle of the hydrogel was detected in each group. Human bone mesenchymal stem cells were seeded onto four kinds of hydrogels. After cells attached, scanning electron microscope and LIVE/DEAD staining were done to observe cell-hydrogel compounds. Human bone marrow mesenchymal stem cells were co-cultured with ordinary culture medium (control) or four kinds of hydrogels for 1, 3, 5, 7 days, and the cell proliferation was detected by cell counting kit-8 assay. The four kinds of hydrogels were put into 24-well culture plates with addition of PBS containing TGF-β1, and 1 hour later, immunofluorescence staining was done. RESULTS AND CONCLUSION:(1) The contact angles of groups A and C were larger than those of groups B and D. (2) Under the scanning electron microscope, groups A and C had little cells attached on the hydrogel surface, but there were many cells on the hydrogel surface in groups B and D. (3) LIVE/DEAD staining showed groups A and C had little living cells, and conversely groups B and D had many living cells. (4) The results of cell counting kit-8 demonstrated that as the incubation time went on, cell proliferation activity of five different groups increased with no difference at the same time point. (5) Findings from the immunofluorescence staining showed that groups A and B had very weak fluorescence, while groups C and D had stronger green fluorescence. In conclusion, PEG hydrogels grafted with RGD and HSNGLPL polypeptides can auto-recruit TGF-β1, and have good biocompatibility.