Cyclooxygenase-2 inhibitor and interferon-β synergistically induce apoptosis in human hepatoma cells in vitro and in vivo

Abstract

Recent clinical trials have shown that interferon (IFN) is effective for chemoprevention against hepatocellular carcinoma (HCC). However, it remains controversial as to whether IFN exerts direct cytotoxicity against HCC. Cyclooxygenase (COX)-2 also plays a role in hepatocarcinogenesis and may mediate resistance to apoptosis in HCC. Therefore, we aimed to elucidate the combined effect of COX-2 inhibitor, NS-398, and IFN on in vitro growth suppression of HCC using 3 hepatoma cell lines (HepG2, PLC/PRF/5, and Huh7) and in vivo nude mouse xenotransplantation model using Huh7 cells. Only minimal growth inhibition was observed after treatment with IFN-ß alone in the 3 hepatoma cell lines. In contrast, treatment with NS-398 and IFN-ß synergistically inhibited cell proliferation in dose-and time-dependent manner. Apoptosis was identified by 4',6-diamidino-2phenylindole dihydrochloride and fluorescent staining. IFN-ß up-regulated the expression of TRAIL, while NS-398 increased the expression of TRAIL receptors (especially of death receptor 5). Subsequently, activation of caspase-8 and caspase-3 was observed following the treatment with NS-398 and IFN-ß. Blockade of TRAIL with a specific antibody attenuated this apoptosis. Furthermore, we found that IFN-ß up-regulated COX-2 expression in Huh7 cells, and NS-398 might suppress the up-regulated COX-2 activity downstream of IFN signaling. In vivo experiment showed the combined regimen with NS-398 and IFN-ß reduced the growth of xenotransplated HCCs in nude mice. In conclusion, NS-398 is sufficient to overcome IFN resistance in hepatoma cells through the TRAIL/TRAIL receptor pathway, therefore, the combination would appear to be a new therapeutic regimen for HCC.

Identification of IL‐1β and LPS as optimal activators of monolayer and alginate‐encapsulated mesenchymal stromal cell immunomodulation using design of experiments and statistical methods

“…IFN-b activation of MSCs led to increases in macrophage TNF-a and antagonized its attenuation by IL-1b-activated MSC CM, despite the synergistic interaction of IFN-b with IL-1b to increase PGE2 secretion. Upregulation of NF-jB activity and COX-2 transcription by IFN-b has been reported in Huh7 cells 43 and microglia 44 and IFN-c has previously been reported to increase COX-2 expression and secretion of PGE2 from MSCs. 45,46 However, discrepancies in cell type and source as well as higher concentrations of IFN-c make comparisons with the current study difficult.…”

Enhanced Death Ligand-Induced Apoptosis in Cutaneous SCC Cells by Treatment with Diclofenac/Hyaluronic Acid Correlates with Downregulation of c-FLIP

“…Enhancement of TRAIL-mediated apoptosis by NSAIDs has been occasionally related to decreased levels of survivin (Gaiser et al, 2008;Lu et al, 2008). More frequently, however, upregulation of TRAIL-R1/DR5 has been reported after NSAID treatment, in particular after treatment with celecoxib (Liu et al, 2006;Nakamoto et al, 2006;Yamanaka et al, 2006;He et al, 2008). Also some upregulation of CD95, TNF-R1, and DR4 surface expression has been reported in hepatocellular carcinoma after COX-2 inhibition by celecoxib (Kern et al, 2006), but these death receptors were not involved in colon and prostate cancer cells after sulindac sulfide treatment, where DR5 was selectively upregulated (Huang et al, 2001).…”

Inhibitory Effect of IFN-β, on the Antitumor Activity of Celecoxib in U87 Glioma Model

“…Lee et al 14) demonstrated an increased antiproliferative effect by the combination of IFN-α· (1,000 IU/mL) and celecoxib (10-50 µM/mL) or curcumin (10-50 µM/mL) in non-small cell lung cancer (NSCLC). Nakamoto et al 17) showed an enhanced antitumor effect by the combined use of IFN-β (5 × 10 4 IU, 3/week) and NSAID, NS-398 (15 mg/kg, every day) in nude mice bearing hepatocellular carcinoma (HCC). In the present study, IFN-β and celecoxib demonstrated an antiproliferative activity on U87 human glioma cells in a dose-dependent manner, respectively.…”

“…It has been reported that IFN-α/β up-regulates the amount of COX-2 protein and mRNA levels via STAT activation in human hepatoma cells or NSCLC, A549 cells 1,14,17) . The relationship between maximal tolerated doses of IFN-β and the induction of down-regulation of STAT1 signaling has not yet been fully elucidated.…”