Effects of analogs of indole-3-carbinol cyclic trimerization product in human breast cancer cells

Ligands and agonists of the aryl hydrocarbon receptor AhR: Facts and myths

The aryl hydrocarbon receptor (AhR) belongs to the essential helix-loop-helix transcription factors family. This receptor has a central role in determining host physiology and a variety of pathophysiologies ranging from inflammation and metabolism to cancer. AhR is a ligand-driven receptor with intricate pharmacology of activation depending on the type and quantity of ligand present. Therefore, a better understanding of AhR ligands per se is critical to move the field forward. In this minireview, we clarify some facts and myths about AhR ligands and how further studies could shed light on the true nature of AhR activation by these ligands. The review covers select chemical classes and explores parameters that qualify them as true receptor ligands.

Adverse outcome pathway from activation of the AhR to breast cancer-related death

Adverse outcome pathways (AOPs) are formalized and structured linear concepts that connect one molecular initiating event (MIE) to an adverse outcome (AO) via different key events (KE) through key event relationships (KER). They are mainly used in eco-toxicology toxicology, and regulatory health issues. AOPs must respond to specific guidelines from the Organization for Economic Co-operation and Development (OECD) to weight the evidence between each KE. Breast cancer is the deadliest cancer in women with a poor prognosis in case of metastatic breast cancer. The role of the environments in the formation of metastasis has been suggested. We hypothesized that activation of the AhR (MIE), a xenobiotic receptor, could lead to breast cancer related death (AO), through different KEs, constituting a new AOP. An artificial intelligence tool (AOP-helpfinder), which screens the available literature, was used to collect all existing scientific abstracts to build a novel AOP, using a list of key words. Four hundred and seven abstracts were found containing at least a word from our MIE list and either one word from our AO or KE list. A manual curation retained 113 pertinent articles, which were also screened using PubTator. From these analyses, an AOP was created linking the activation of the AhR to breast cancer related death through decreased apoptosis, inflammation, endothelial cell migration, angiogenesis, and invasion. These KEs promote an increased tumor growth, angiogenesis and migration which leads to breast cancer metastasis and breast cancer related death. The evidence of the proposed AOP was weighted using the tailored Bradford Hill criteria and the OECD guidelines. The confidence in our AOP was considered strong. An in vitro validation must be carried out, but our review proposes a strong relationship between AhR activation and breast cancer-related death with an innovative use of an artificial intelligence literature search.

Molecularly imprinted solid phase extraction in an efficient analytical protocol for indole-3-methanol determination in artificial gastric juice

Molecularly imprinted solid phase extraction was employed in separation step of new and efficient analytical protocol for analysis of indole-3-methanol.

D-pinitol promotes apoptosis in MCF-7 cells via induction of p53 and Bax and inhibition of Bcl-2 and NF-κB

Development of drugs from natural products has been undergoing a gradual evoluation. Many plant derived compounds have excellent therapeutic potential against various human ailments. They are important sources especially for anticancer agents. A number of promising new agents are in clinical development based on their selective molecular targets in the field of oncology. D-pinitol is a naturally occurring compound derived from soy which has significant pharmacological activitites. Therefore we selected D-pinitol in order to evaluate apoptotic potential in the MCF-7 cell line. Human breast cancer cells were treated with different concentrations of D-pinitol and cytotoxicity was measured by MTT and LDH assays. The mechanism of apoptosis was studied with reference to expression of p53, Bcl-2, Bax and NF-kB proteins. The results revealed that D-pinitol significantly inhibited the proliferation of MCF-7 cells in a concentration-dependent manner, while upregulating the expression of p53, Bax and down regulating Bcl-2 and NF-kB. Thus the results obtained in this study clearly vindicated that D-pinitol induces apotosis in MCF-7 cells through regulation of proteins of pro- and anti-apoptotic cascades.

Synthesis and biological evaluation of a gamma-cyclodextrin-based formulation of the anticancer agent 5,6,11,12,17,18,23,24-octahydrocyclododeca[1,2-b:4,5-b':7,8-b'':10,11-b''']tetraindole (CTet)

5,6,11,12,17,18,23,24-Octahydrocyclododeca[1,2-b:4,5-b':7,8-b'':10,11- b''']tetrai ndole (CTet), an indole-3-carbinol (I3C) metabolite endowed with anticancer properties, is poorly soluble in the solvents most frequently used in biological tests. This study indicates that the use of gamma-cyclodextrin (gamma-CD) avoids this problem. Formulated with gamma-CD CTet is a potent inhibitor of DNA synthesis in both estrogen receptor positive (MCF-7) and estrogen receptor negative (MDA-MB-231) human breast cell lines (IC50 = 1.20 +/- 0.04 microM and 1.0 +/- 0.1 microM, respectively).

Synthetic dimer of indole-3-carbinol: second generation diet derived anti-cancer agent in hormone sensitive prostate cancer

BACKGROUND

Cruciferous vegetables have been found to have anti-prostate cancer effects. The active compounds mediating these effects include indoles such as indole-3-carbinol (I3C) and isothiocyanates. I3C is unstable having tissue tropic effects and clinical utility has been partly addressed by the synthesis of a more stable dimer diindolylmethane (DIM).

METHODS

Anti-proliferative activity was measured by XTT assay and cytosolic proteins quantitated by Western blot analysis.

RESULTS

DIM (IC(50) 50 microM) is a better anti-proliferative agent than I3C (IC(50) 150 microM) in androgen dependent LNCaP cells, inhibits DNA synthesis, and growth of R1881 stimulated LNCaP cells. Androgen receptor (AR), cyclin D1, and cdk4, induced by R1881, are downregulated by DIM. DIM downregulates phosphorylated Akt and phosphatidyl inositol 3-kinase and downstream inhibition of cyclin D1 and cdk4.

CONCLUSION

These studies provide evidence that DIM is a second-generation chemopreventive agent with a viable cellular target and has clinical potential as an anti-prostate cancer chemopreventive.