An assessment of poly (ADP-ribose) polymerase-1 role in normal and cancer cells

Poly (ADP-ribose) polymerase (PARP) is a superfamily of 18 proteins characterized by the PARP homology domain, the catalytic domain. This catalytic domain helps in the ADP-ribosylation of various acceptor proteins using nicotinamide adenine dinucleotide (NAD+) as a donor for ADP-ribose. PARP-1 and PARP-2 carry out 80% of poly-ADP-ribosylation of cellular protein. Hence, their combined knockout results in embryonic lethality of mice. PARP-1 consists of three major domains, namely, DNA binding domain, automodification domain, and a catalytic domain. These domains further consist of subdomains and motifs, which helps PARP-1 in a diverse function. PARP-1 is mainly involved in DNA damage detection and repair, but emerging evidence suggests its role in many other functions such as DNA synthesis, replication, apoptosis, necrosis, and cancer progression. Herein, we review the current state of the PARP-1 role in DNA damage repair and other biological processes including epithelial to mesenchymal transition (EMT). We have also observed the role of PARP-1 in modulating EMT regulators like E-cadherin, Vimentin, Claudin-1, Snail, Smad-4, Twist-1, and β-catenin. Here, we have also attempted to relate the role of PARP-1 in EMT of cancer cells.

Design, Synthesis, and Anticancer Potential of the Enzyme (PARP-1) Inhibitor with Computational Studies of New Triazole, Thiazolidinone, - Thieno [2, 3-d] Pyrimidinones

Background:

Thienopyrimidine, triazole and thiazolidinone derivatives have recently gained attention due to their effective pharmacological activities. They show antioxidant, antitumor, antimicrobial, antiviral, anti-inflammatory and analgesic properties.

Objective:

Synthesis of new ethyl 2-amino-4-isopropyl-5-methylthiophene-3-carboxylate (2) was used as a starting material to produce 2-mercapto-methylthienopyrimidinone (3), (4) and 2- hydrazinyl-methylthienopyrimidinone (5), through high yields and evaluating anticancer activities.

Method:

A series of novel Schiff's bases (6-9) were produced after treatment of (5) with aldehydes. Triazolopyrimidinones (6a, 7a, 8a, 9a) were produced from cyclization of benzylidene (6-9) using Br2 / AcOH or dry pyridine /Ac2O. Thiazolidinones (6b, 7b, 8b, 9b) were synthesized from benzylidene (6-9) with mercaptoacetic acid.

Results:

All the compounds were synthesized in good yields (55-85%) in a regularly actual system under mild condition. The new compounds have been established by means of diverse spectroscopic ways as IR, NMR and MS. The newly synthesized compounds were evaluated for their antiproliferative activity against the breast MCF-7 carcinoma cell line. Compound (7) showed promising anticancer activity with IC50 of 6.9 μM, and 40.8% of antioxidant effect as DPPH inhibition. Molecular docking of (7) showed ΔG values of-20.54 kcal/ mol and -25.60 kcal/ mol. Molecular dynamics simulation of (7) in complex with PARP-1 revealed RMSD of 3.00 Ǻ.

Conclusion:

The QSAR study confirmed the presence of a relationship between anticancer activity and subdivided surface area descriptors with coefficient r2 = 0.98 with high predictive power.