(Bis)phosphonic Acid-Functionalized Poly(ethyleneimine)–Poly(amido amine)s for Selective In Vitro Transfection of Osteosarcoma Cells

Abstract

Osteosarcoma is aggressive bone cancer, whose treatment has not changed significantly for the past few decades. Although gene therapy methods have emerged as potential treatment routes, the need for efficient and nontoxic gene delivery systems targeting osteosarcoma cells remains a challenge. Highmolecular-weight poly(ethyleneimine)s (PEIs) are used as universal transfection agents; however, they cause significant cytotoxicity. On the other hand, poly(amido amine)s (PAAs) are biocompatible, biodegradable polymers with promising transfection efficiency, which should be improved further. In this paper, we combined low-molecular-weight branched PEI (1800 Da) and PAA macromers functionalized with various amounts of (bis)phosphonic acid groups and pentanol (via 5-amino-1-pentanol (AP)). The (bis)phosphonic acid groups on these polymers (PAEIs) are intended to facilitate bone targeting. The molecular weights of the PAEI polymers were between 2600 and 8600 g/mol. Their cytotoxicities and green fluorescence protein (GFP) transfection efficiencies were tested on an osteosarcoma cell line (U-2 OS cells), which is challenging to transfect, and healthy muscle cells (C2C12). Both the cytotoxicity and transfection efficiency of PAEIs were affected by the phosphonic acid (via APA, 2-aminoethyl phosphonic acid) or bisphosphonic acid (via ALE, sodium alendronate) content of the polymers. PAEIs are more cytocompatible than both linear and branched 25 kDa PEI. ALE-containing PAEIs provided better transfection than APA-containing ones. The most efficient PAEI polymer, containing a 0.7:0.3 AP/ALE ratio, displayed a transfection efficiency that was five times higher than that of 25 kDa PEI with dramatically better cytocompatibility. This is comparable to FuGENE, but PAEI is more advantageous in selective transfection of the U-2 OS. This set of polymers may be promising candidates for targeted gene therapy of osteosarcoma.

Phosphonate-Modified Cellulose Nanocrystals Potentiate the Th1 Polarising Capacity of Monocyte-Derived Dendritic Cells via GABA-B Receptor

“…In this context, a good tropism of CNCs and (bis)phosphonate-CNC conjugates for bone tissues 7,9 makes them great candidates for the treatment of bone metastasis and osteosarcoma. 9,10 Additionally, we demonstrated that the delivery of ApA via CNCs also potentiates beneficial immunomodulatory effects of ApA up to 5 times, as compared to the soluble form of ApA. These results suggest that, in potential clinical application, a smaller amount of bisphosphonates would be required if they are delivered via CNC, which is especially important when adverse clinical effects of these drugs are considered.…”

“… 8 In line with this, the delivery of anti-osteoporotic phosphonates and cytotoxic drugs via CNCs has been considered an attractive approach for the therapy of osteosarcoma and bone metastasis. 9 , 10 Namely, phosphonates, such as alendronate (ALN) and 3-aminopropyl phosphonic acid (ApA), were shown to inhibit osteoclast-mediated bone resorption and increase bone mineralisation. 11 , 12 Moreover, we showed previously that ALN and ApA conjugated to CNCs display good biocompatibility and the growth of primary human osteoblasts, 13 all of which could be desirable in treating bone diseases with prominent osteolysis.…”

Polytrimethylenimines: Highly Potent Antibacterial Agents with Activity and Toxicity Modulated by the Polymer Molecular Weight

“…Derivatives of PEI have been extensively studied as antimicrobial agents, , as nonviral transfection vectors, , and for other biomedical applications. , The results, however, have shown that the polymer exhibits relatively high cytotoxicity, which limits its applications to nonmedical uses such as antibacterial coatings or paints. , On the other hand, polytrimethylenimine (PTMI), an analogue of PEI with a three-methylene spacer between amine groups, has received substantially lower attention. Its dendrimeric form has gained popularity as a nonviral transfection vector and in drug delivery systems, , although there are very limited reports on a linear form of PTMI. − Different N -methylated PTMI derivatives were synthesized; ,, however, they have not been the subject of antimicrobial studies.…”

“…13 Studies also show that they are able to improve bacterial susceptibility for β-lactam antibiotics. 15 Derivatives of PEI have been extensively studied as antimicrobial agents, 16,17 as nonviral transfection vectors, 18,19 and for other biomedical applications. 19,20 The results, however, have shown that the polymer exhibits relatively high cytotoxicity, which limits its applications to nonmedical uses such as antibacterial coatings or paints.…”

“…15 Derivatives of PEI have been extensively studied as antimicrobial agents, 16,17 as nonviral transfection vectors, 18,19 and for other biomedical applications. 19,20 The results, however, have shown that the polymer exhibits relatively high cytotoxicity, which limits its applications to nonmedical uses such as antibacterial coatings or paints. 20,21 On the other hand, polytrimethylenimine (PTMI), # an analogue of PEI with a three-methylene spacer between amine groups, has received substantially lower attention.…”