Cryptopleurine Targets NF-κB Pathway, Leading to Inhibition of Gene Products Associated with Cell Survival, Proliferation, Invasion, and Angiogenesis

Abstract

BackgroundCryptopleurine, a phenanthroquinolizidine alkaloid, was known to exhibit anticancer activity; however, the underlying mechanism is poorly understood. Because the nuclear factor-κB (NF-κB) transcription factors control many physiological processes including inflammation, immunity, and development and progression of cancer, we investigated the effects of cryptopleurine on tumor necrosis factor alpha (TNF-α)-induced NF-κB activation pathway and on the expression of NF-κB-regulated gene products associated with many pathophysiological processes.Methodology and Principal FindingMDA-MB231, MDA-MB435, MCF-7, HEK293, RAW264.7 and Hep3B cells were used to examine cryptopleurine's effect on the NF-κB activation pathway. Major assays were promoter-reporter gene assay, electrophoretic mobility shift assay (EMSA), in vitro immune complex kinase assay, real-time PCR, Western blot analysis, and Matrigel invasion assay. Experiments documenting cell proliferation and apoptosis were analyzed by MTT method and flow cytometry, respectively. The results indicated that cryptopleurine suppressed the NF-κB activation through the inhibition of IκB kinase (IKK) activation, thereby blocking the phosphorylation and degradation of the inhibitor of NF-κB alpha (IκBα) and the nuclear translocation and DNA-binding activity of p65. The suppression of NF-κB by cryptopleurine led to the down-regulation of gene products involved in inflammation, cell survival, proliferation, invasion, and angiogenesis.Conclusions and SignificanceOur results show that cryptopleurine inhibited NF-κB activation pathway, which leads to inhibition of inflammation, proliferation, and invasion, as well as potentiation of apoptosis. Our findings provide a new insight into the molecular mechanisms and a potential application of cryptopleurine for inflammatory diseases as well as certain cancers associated with abnormal NF-κB activation.

PMS1077 Sensitizes TNF-α Induced Apoptosis in Human Prostate Cancer Cells by Blocking NF-κB Signaling Pathway

“…TNF-α can trigger both NF-κB and apoptosis signaling simultaneously, so suppression TNF-α induced NF-κB signaling can potentiate TNF-α induced apoptosis [31], [32], [33], [34], [36], [37]. In the present work, we found that PMS1077 can down-regulate the TNF-α induced expression of the anti-apoptotic Bcl-xL, Bcl-2 and survivin gene, and significantly potentiates TNF-α induced cleavage of PARP.…”

“…NF-κB signaling antagonizes TNF-α and chemotherapeutic agents induced apoptosis by promoting the transcription of anti-apoptotic genes, such as c-FLIP, cIAP-1, cIAP-2, XIAP, survivin, Bcl-xL and Bcl-2. In this way, blocking of NF-κB signaling can potentiate TNF-α induced apoptosis [31], [32], [33], [34]. We then determined whether PMS1077 can modulate the TNF-α induced expression of the anti-apoptosis genes Bcl-xL, Bcl-2 and survivin in DU145 cells.…”

“…NF-κB signaling antagonizes TNF-α and chemotherapeutic agents induced apoptosis by inducing the transcription of anti-apoptotic genes, such as c-FLIP, cIAP-1, cIAP-2, XIAP, survivin, Bcl-xL, and Bcl-2 [34], [35]. TNF-α can trigger both NF-κB and apoptosis signaling simultaneously, so suppression TNF-α induced NF-κB signaling can potentiate TNF-α induced apoptosis [31], [32], [33], [34], [36], [37].…”

Concomitant Loss of p120-Catenin and β-Catenin Membrane Expression and Oral Carcinoma Progression with E-Cadherin Reduction

“…Since previous studies suggested the involvement of isoform shift from 3 to 1 in carcinoma progression [16,33], we treated cells with tumor stimulus (TGF-β, EGF and TNF-α) that facilitate the progression [34–36] and examined the shift. Unexpectedly, carcinoma cells did not show the shift.…”

4′,6-Dihydroxy-4-methoxyisoaurone Inhibits the HIF-1α Pathway Through Inhibition of Akt/mTOR/p70S6K/4E-BP1 Phosphorylation

“…The ability of cells to invade through Matrigel-coated filters (invasion) was determined using a modified 24-well Boyden chamber (Corning Costar, Cambridge, MA, USA; 8-mm pore size) as previously described (24). HeLa cells were seeded at a density of 5 × 10 4 cells in 100 ml DMEM containing 10% FBS in the upper compartment of the transwell.…”