Design and screening of antisense oligodeoxynucleotides against PAI-1 mRNA in endothelial cells in vitro

Expression of human beta-defensin-2 in intratumoral vascular endothelium and in endothelial cells induced by transforming growth factor beta

Human beta-defensin-2 (hBD-2) is a small cationic peptide originally identified from psoriatic skin lesions as an antimicrobial agent of the innate immune system. The expression of hBD-2 is believed to be induced exclusively in epithelial cells by microbial components and certain proinflammatory cytokines, such as interleukin-1 beta (IL-1 beta). In this study, we report, for the first time, that hBD-2 is expressed in vascular endothelial cells associated with oral squamous cell carcinoma (OSCC) and Kaposi's sarcoma lesions, but not in that of normal stroma. Expression of hBD-2 in vascular endothelial cells was further substantiated by in vitro experiments using cultured human umbilical vein endothelial cells (HUVECs). Transforming growth factor beta1 (TGF beta 1) and IL-1 beta, two well-known tumorigenic inflammatory mediators, induce hBD-2 transcript and peptide expression in HUVECs. However, TGF beta 1 does not stimulate hBD-2 expression in oral epithelial cells. In addition, proinflammatory cytokines and microbial reagents do not induce the expression of hBD-1 and hBD-3 in HUVECs. Since hBD-2 has been shown to modulate migration, proliferation, and tube formation of HUVECs in vitro and participate in immune cell trafficking, its expression in vascular endothelial cells located within malignant lesions may play a role in tumor angiogenesis and cancer metastasis.

Antisense oligonucleotides targeting midkine induced apoptosis and increased chemosensitivity in hepatocellular carcinoma cells

AIM

Overexpression of midkine (MK) has been observed in many malignancies. This aim of this study is to screen for suitable antisense oligonucleotides (ASODN) targeting MK in hepatocellular carcinoma (HCC) cells and evaluate its antitumor activity.

METHODS

Ten ASODN targeting MK were designed and synthesized. After transfection with ASODN, cell proliferation was analyzed with MTS[3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] assay. In addition, MK mRNA, protein levels, as well as apoptosis and caspase-3 activity were also examined in HepG2 cells. Cell proliferation was then analyzed after treatment with both ASODN and chemotherapeutic drugs.

RESULTS

In this experiment, the ASODN5 among the 10 ASODN showed higher inhibitory activity against proliferation of hepatocellular carcinoma cells in a dose-dependent manner. In HepG2 cells, ASODN5 could significantly reduce the MK mRNA level and protein content. After transfection with ASODN5 for 48 h, accompanied with a decline of survivin and Bcl-2 protein content, a remarkable increase of apoptosis and caspase-3 activity was observed in HepG2 cells. Furthermore, ASODN5 transfer can significantly increase chemosensitivity in HepG2 cells.

CONCLUSION

Antisense oligonucleotides targeting MK shows therapeutic effects on HCC; ASODN5 has the possibility to be developed as an effective antitumor agent.