Vanillin suppresses in vitro invasion and in vivo metastasis of mouse breast cancer cells

Plant phenolics regulate neoplastic cell growth and survival: a quantitative structure-activity and biochemical analysis

The anti-tumour activities of many plant phenolics at high concentrations (>100 micromol/L) suggest their potential use as dietary supplements in cancer chemoprevention and cancer chemotherapy. However, it is not clear what impact phenolic compounds have at the physiological concentrations obtained through consumption of high phenolic diets on neoplastic cells. In the present study, 54 naturally occurring phenolics were evaluated at physiologically relevant concentrations for their capacity to alter PC12 cell viability in response to serum deprivation, the chemotherepeutic agent etoposide, and the apoptogen C2-ceramide. Surprisingly, novel mitogenic, cytoprotective, and antiapoptotic activities were detected. Quantitative structure-activity relationship modelling indicated that many of these activities could be predicted by compound lipophilicity, steric bulk, and (or) antioxidant capacity, with the exception of inhibition of ceramide-induced apoptosis. Where quantitative structure-activity relationship analysis was insufficient, biochemical assessment demonstrated that the benzoate orsellinic acid blocked downstream caspase-12 activation following ceramide challenge. These findings demonstrate substantive mitogenic, cytoprotective, and antiapoptotic biological activities of plant phenolics on neoplastic cells at physiologically relevant dietary concentrations that should be considered in chemopreventive and chemotherapeutic strategies.

Radioprotection of 4-hydroxy-3,5-dimethoxybenzaldehyde (VND3207) in culture cells is associated with minimizing DNA damage and activating Akt

Vanillin is a naturally occurring compound and food-flavoring agent with antioxidant and antimutagenic activities. In present study, we explored the radioprotective effect of a novel vanillin derivative VND3207 (4-hydroxy-3,5-dimethoxybenzaldehyde). VND3207 has a much higher potential in scavenging hydroxyl radical and superoxide radical than vanillin as indicated in the ESR spin-trapping measurement, and it can effectively protect plasmid DNA against 10-50 Gy gamma-ray induced breaks in vitro at the concentrations as low as 10-20 microM. Using human lymphoblastoid AHH-1 cells and human fibroblastoid HFS cells, we demonstrated that VND3207 at 5-40 microM concentrations significantly attenuated the inhibition of proliferation and occurrence of apoptosis produced by 1-8 Gy gamma-irradiation. In the cultured cells, VND3207 significantly decreased the initial production and residual level of DNA double-strand breaks (DSBs) induced by 2 or 8 Gy irradiation. Treatment of VND3207 enhanced the level of DNA-PKcs protein, a critical component of DNA DSB repair pathway in the cells with or without gamma-irradiation. Consistently, the phosphorylation of Akt protein, a mediator of survival signal, as well as its substrate GSK3beta was concurrently increased by VND3207. Our results suggest that VND3207 has radioprotection effect through its capabilities as a powerful antioxidant, in minimizing DNA damage, and activating survival signal Akt pathway, and it may be of value in the development of radioprotective compounds.

Induction of apoptosis and autophagic cell death by the vanillin derivative 6-bromine-5-hydroxy-4-methoxybenzaldehyde is accompanied by the cleavage of DNA-PKcs and rapid destruction of c-Myc oncoprotein in HepG2 cells

Autophagy is a regulated lysosomal pathway involving the bulk degradation of cytoplasmic contents, and is an emerging attractive therapeutic approach for treating cancers. In the present study, we demonstrates that bromovanin (6-bromine-5-hydroxy-4-methoxybenzaldehyde), a vanillin derivative, exhibits a potent antiproliferative effect on a broad spectrum of cancer cell lines, but it induces apoptosis with a large variation in extent on different cancer cell lines. Ultrastructural observation in transmission electron microscopy reveals that autophagy is another type of cell death induced by bromovanin in HepG2 cells. Treatment with bromovanin significantly increases cellular ROS level as well as elicits DNA double-strand breaks as indicated by comet assay and the increased phosphorylated H2AX. Cleavage and inactivation of DNA-PKcs induced by bromovanin is found to occur concurrently with a rapid destruction of c-Myc oncoprotein. These multiple effects of bromovanin, especially the induction of both apoptosis and autophagy, make it very appealing for the development as a novel anticancer drug.

Development of a LC-ESI/MS/MS assay for the quantification of vanillin using a simple off-line dansyl chloride derivatization reaction to enhance signal intensity

Vanillin is responsible for producing the familiar smell of vanilla. Vanillin has many similarities with other flavor phenolic compounds and could potentially show similar pharmacological activity. A previously published analytical method was adapted, developed and tested. Vanillin was extracted from rat plasma using protein precipitation with acetone. Prior to LC-ESI/MS/MS analysis, an aliquot of the supernatant was used to proceed to the derivatization of vanillin and the internal standard with dansyl chloride to enhance signal intensity in positive electrospray mode. The chromatography was performed on a 100 x 2.1 mm C8 column and an isocratic mobile phase composed of 75:25 acetonitrile:0.5% formic acid in water with a flow rate fixed at 500 microL/min. A linear (weighted 1/concentration) relationship was used to perform the calibration over an analytical range of 10-10,000 ng/mL. The intra-batch precision and accuracy at the limit of quantitation (10 ng/mL), medium (500 ng/mL) and high (10,000 ng/mL) concentrations were 10.7, 7.0 and 7.2% and 103.5, 108.0 and 100.1%, respectively. The observed recovery was greater than 87% and no significant ionization suppression or matrix effect was observed. This LC-ESI/MS/MS method for the determination of vanillin in rat plasma provided results within generally accepted criteria used for bioanalytical assay.

Silencing the hsp25 gene eliminates migration capability of the highly metastatic murine 4T1 breast adenocarcinoma cell

The 25-kDa heat shock protein (Hsp25) is associated with various malignancies and is expressed at high levels in biopsies as well as circulating in the serum of breast cancer patients. In this study, we used RNA interference technology to silence the hsp25 gene in 4T1 breast adenocarcinoma cells, known as a poorly immunogenic, highly metastatic cell line. We demonstrate that transfection of 4T1 cells with short interference RNA-Hsp25 dramatically inhibits proliferation as compared with control transfected cells. In addition, we show that 4T1 cells transfected with short interference RNA-Hsp25 abrogates tumor migration potential by a mechanism that is in part due to the repression of matrix metalloproteinase 9 expression and a concomitant upregulation of its antagonist, tissue inhibitor metalloproteinase 1. Taken together, these findings provide a model system for the study of metastatic potential of tumors and are suggestive of an earlier unrecognized role for Hsp25 in tumor migration.