β-Like DNA polymerases and prospects for their use as targets in chemotherapy of tumors

DNA polymerases β are enzymes that perform repair of damaged DNA. In the cells of malignant tumors, there is a change in the production and properties of these enzymes, which is accompanied by altered viability of tumor cells. Analysis of the publications available in Russian and international databases (Pubmed, Elsevier) on the structure and properties of DNA polymerases β and their role in cell growth and proliferation, published over the past 20 years, has shown overexpression of genes encoding β-like DNA polymerases in many types of malignant tumors cells. This explains the maintenance of their viability and proliferative activity. Targeted inhibition of β-like DNA polymerases is accompanied by antiproliferative and antitumor effects. Stable paramagnetic isotopes of magnesium (25Mg2+) or other divalent metals (43Ca2+ and 67Zn2+) with uncompensated nuclear spin isotopes, as well as short single-stranded polydeoxyribonucleotides, can be used as promising antitumor pharmacophores.

Anti-cancer activity of ultra-short single-stranded polydeoxyribonucleotides

One of the features that differentiate cancer cells is their increased proliferation rate, which creates an opportunity for general anti-tumor therapy directed against the elevated activity of replicative apparatus in tumor cells. Besides DNA synthesis, successful genome replication requires the reparation of the newly synthesized DNA. Malfunctions in reparation can cause fatal injuries in the genome and cell death. Recently we have found that the ultra-short single-stranded deoxyribose polynucleotides of random sequence (ssDNA) effectively inhibit the catalytic activity of DNA polymerase [Formula: see text]. This effect allowed considering these substances as potential anti-tumor drugs, which was confirmed experimentally both in vitro (using cancer cell cultures) and in vivo (using cancer models in mice). According to the obtained results, ssDNA significantly suppresses cancer development and tumor growth, allowing consideration of them as novel candidates for anti-cancer drugs.

Radiation-Chemical Biotechnology for Producing Ultrashort (50-100n) Single-Chain Polydeoxyribonucleotides with Anticancer Activity

The fundamental possibility of obtaining ultrashort (50n-100n) single-stranded polydeoxyribonucleotides by the method of radiation-chemical destruction of total yeast DNA was established and their anticancer activity was shown.

L, D-Polydeoxyribonucleotides to provide an essential inhibitory effect on DNA polymerase β of human myeloid leukemia HL60 cells

The inhibitory effect of D and L-polynucleotides of a given length (40-50n) on the catalytic activity of DNA polymerase β isolated from chromatin cells of acute myeloid leukemia HL-60 was evaluated. The synthesized L enantiomer was found to have a higher inhibitory activity than the synthesized and isolated D enantiomers of polynucleotides. The work also proposes a biophysical model that describes this effect.

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The inhibitory activity of L, D-polydeoxyribonucleotides of various compositions was evaluated.

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Inhibition of DNA polymerase β is due to a nonspecific interaction between the enzyme and the substrate.

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L-polynucleotide exhibits the highest inhibiting activity, compared to the D-enantiomers.