Nitric Oxide-Releasing Aspirin Suppresses NF-κB Signaling in Estrogen Receptor Negative Breast Cancer Cells in Vitro and in Vivo

Abstract

Estrogen receptor negative (ER(−)) breast cancer is aggressive, responds poorly to current treatments and has a poor prognosis. The NF-κB signaling pathway is implicated in ER(−) tumorigenesis. Aspirin (ASA) is chemopreventive against ER(+) but not for ER(−) breast cancers. Nitric oxide-releasing aspirin (NO-ASA) is a safer ASA where ASA is linked to an NO-releasing moiety through a spacer. In vitro, we investigated anti-proliferation effects of NO-ASA (para-and meta-isomers) against ER(−) breast cancer cells MDA-MB-231 and SK-BR-23, effects on NF-κB signaling, and reactive oxygen species by standard techniques. In vivo, effects of NO-ASA were evaluated in a mouse xenograft model using MDA-MB-231 cells. p-NO-ASA inhibited the growth of MDA-MB-231 and SK-BR-3 cells at 24 h, the respective IC50s were 13 ± 2 and 17 ± 2 μM; ASA had an IC50 of >3000 μM in both cell lines. The IC50s for m-NO-ASA in MDA-MB-231 and SK-BR-3 were 173 ± 15 and 185 ± 12 μM, respectively, therefore, implying p-NO-ASA as a stronger inhibitor of growth p-NO-ASA reduced cell growth by inhibiting proliferation, inducing apoptosis and causing OPEN ACCESSMolecules 2015, 20 12482 G0/G1 cell cycle block. Activation of NF-κB was inhibited by both isomers as demonstrated by decreases in NF-κB-DNA binding and luciferase activity at 24 h, However, m-NO-ASA produced transient effects at 3 h such as increased NF-κB-DNA-binding, increased levels of nuclear p50, even though both isomers inhibited IκB degradation. Increase in nuclear p50 by m-NO-ASA was associated with translocation of p50 in to the nucleus as observed by immunoflouresence at 3 h. NO-ASA induced reactive oxygen species (ROS) as evidenced by overall increases in both H2DCFDA (2′,7′-dichlorodihydrofluorescein) and DHE (dihydroethidium)-derived fluorescence. Inhibition of ROS by N-acetyl-cysteine reversed the m-NO-ASA-mediated translocation of p50 in to the nucleus. In xenografts, p-NO-ASA inhibited tumor growth by inhibiting proliferation (PCNA and tumor volume), inducing apoptosis (TUNEL positive cells) and reducing NF-κB expression. Both isomers inhibit cancer cells, inhibit NF-κB pathway and induce ROS, and have potential as anticancer compounds.

Compound C enhances the anticancer effect of aspirin in HER-2-positive breast cancer by regulating lipid metabolism in an AMPK-independent pathway

“…However, the association between aspirin treatment and HER-2-positive breast cancer has not been studied in detail. Nath et al proved that aspirin inhibited HER-2-positive breast cancer SKBR-3 cell growth by regulating nuclear factor κB (NF-κB) activity [31]. Our study indicated that aspirin exerted an anticancer activity in the HER-2-positive breast cancer cell lines AU-565, BT-474 and SKBR-3 by inhibiting their proliferation and colony-forming abilities, regulating cell cycle progression, and inducing apoptosis, through the activation of AMPK signaling.…”

The dichotomous role of H2S in cancer cell biology? Déjà vu all over again

“…It should be noted that although structure-activity studies with NO-aspirin had indicated that NO was pivotal for its anticancer effects [233] it also became apparent that in cases where the spacer was aromatic, the biological actions may have been due to formation of a putative quinone methide (QM) intermediate [234–236]. NO-NSAIDs have shown efficacy in various animal models of cancer, including a rat model of colonic adenocarcinoma [237], Min (AP C Min/+ ) mouse [238], F344 rats treated with the carcinogen, azoxymethane [239], pancreatic cancer [240], urinary bladder cancer [241], and estrogen receptor negative breast cancer [242]. Molecular targets of NO-NSAIDs in cancer have been thoroughly reviewed elsewhere [25, 230].…”

“…High iNOS expression is associated with favorable prognoses in ovarian [242] and lung cancers [284]. Overexpression of iNOS by gene transfer in prostate and colon cancer cells produced enhanced amounts of NO increasing the sensitivity of these cells to cisplatin-induced cell death [345] or to radiation therapy [346].…”

Oleuropein induces apoptosis via abrogating NF‐κB activation cascade in estrogen receptor–negative breast cancer cells

“…Nuclear factor‐κB (NF‐κB) plays an important role in the development of various malignancies, including breast cancer . Previous research has shown that NF‐κB can be constitutively active in ER‐negative breast cancer cell lines, and thus targeting NF‐κB could be an important target for the treatment of ER‐negative breast cancers . In a recent report, oleuropein was reported to modulate IL‐1β–stimulated NF‐κB activation in chondrocytes .…”