Targeting telomerase utilizing zeolitic imidazole frameworks as non-viral gene delivery agents across different cancer cell types

Telomerase, a ribonucleoprotein coded by the hTERT gene, plays an important role in cellular immortalization and carcinogenesis. hTERT is a suitable target for cancer therapeutics as its activity is highly upregulated in most of cancer cells but absent in normal somatic cells. Here, by employing the two Metal-Organic Frameworks (MOFs), viz. ZIF-C and ZIF-8, based biomineralization we encapsulate Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/Cas9 plasmid system that targets hTERT gene (CrhTERT) in cancer cells. When comparing the two biocomposites, ZIF-C shows the better loading capacity and cell viability. The loaded plasmid in ZIF-C is highly protected against enzymatic degradation. CrhTERT@ZIF-C is efficiently endocytosed by cancer cells and the subcellular release of CrhTERT leads to telomerase knockdown. The resultant inhibition of hTERT expression decreases cellular proliferation and causing cancer cell death. Furthermore, hTERT knockdown shows a significant reduction in tumour metastasis and alters protein expression. Collectively we show the high potential of ZIF-C-based biocomposites as a promising general tool for gene therapy of different types of cancers.