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Tumor Discovery Targeted drug delivery systems for the treatment of tumors

in the pDNA backbone) of 20. Furthermore, cell viability linked polyethylenimine and PEG to develop GE11-tethered
was found to decrease in a dose-dependent manner. The polyplexes and evaluated their transfection efficiency in
results revealed that fabricated polyplexes (composed of EGFR-overexpressed tumor cells. The formulated polyplexes
polycationic phosphorous dendrimers and plasmid) had demonstrated efficient gene condensing capacity, improved
reduced positive charge in the system, resulting in minimal transfection efficiency, and specific targeting capabilities .
[81]
cytotoxicity. These outcomes suggested that the fabricated Polyplexes are generally designed for receptor-mediated
phosphorus dendrimers hold promise as an effective gene delivery through systemic routes, facilitating efficient
carrier system for gene delivery in cancer treatment . internalization due to their augmented transfection
[67]
efficiency. In this context, Taschauer et al. evaluated the
(d) Polyplexes
significance of the overexpression of CD49f in both benign
These polymeric nanocarriers are formulated by and malignant tumors . CD49f molecules are associated
[82]
conjugating siRNA/DNA or genes via electrostatic with the phosphatidylinositol 3-kinase and the serine/
interactions between cationic polymers and anionic threonine protein kinase (Akt signaling pathway), which
nucleic acid components. These systems serve the dual play a crucial role in the regulation and development of bone
proposes of protecting sensitive genes from enzyme mesenchymal stem cells and contribute to tumor metastasis
degradation and facilitating controlled release at the tumor in solid cancers such as hemangioma, breast cancer,
site. Polycationic polyplexes show great promise as a drug prostate cancer, and gastric cancer. A nanodimensional
delivery approach for the specific delivery of anticancer molecular conjugate (200 nm) consisting of the CD49f
agents due to their ability to enhance transfection peptide (CYESIKVAVS) and linear polyethyleneimine
efficiency. DNA polyplexes (polymeric-based) and DNA (LPEI) was synthesized for the purpose of targeting
lipoplexes (lipid-based) are systemic gene delivery systems breast tumor lesions. The fabricated polyplexes could be
necessary for cases of tumor metastases, where cancerous aerosolized without particle aggregation. When delivered
cells spread throughout the organism. Polyethyleneimine through intratracheal aerosolization, the system was well-
polyplexes, functionalized with PEG, have been developed tolerated and demonstrated measurable transgene efficacy.
and conjugated with transferrin or epidermal growth Hattori compiled various cationic and anionic polyplexes
factor to facilitate effective DNA (or gene) transfer within with genes to enable their delivery to tumor-targeted sites
tumor cells. This modification masks the surface charge without aggregation with blood components . Surface
[83]
of polyplexes to prevent interactions with systemically modification of cationic polyplexes with anionic polymers
present circulatory components, including erythrocytes, led to the development of a stable drug delivery approach
plasma, and the reticuloendothelial system . Table 5 that effectively delivered pDNA and siRNA to the target
[80]
enlists surface-modified cationic and anionic polyplexes site .
[84]
designed to efficiently deliver nucleic acid in tumors.
Lee et al. explored the successful delivery of branched 4.2.2. Lipid carriers
peptide (GE11) for cancer cells overexpressing EGFR. They Lipid-based nanosystems are extensively utilized for
investigated the use of low molecular weight disulfide cross- targeting and regulating the tumor microenvironment

Table 5. Surface-modified polyplexes and their conjugates for nucleic acid delivery in tumor management

Polyplexes Nucleic acid Conjugate References
Cationic polymers
Lipofectamine 2000 Plasmid DNA Hyaluronic acid (HA) [84]
Chitosan Plasmid DNA Hyaluronic acid [85]
Polyamidoamine Plasmid DNA Hyaluronic acid [86]
Protamine Antisense DNA HA-antisense DNA [87]
Dendrigraft poly-L-lysine Plasmid DNA Chondroitin sulfate [88]
Anionic polymers
Poly-ᵞ-glutamic acid Plasmid DNA Chitosan [89]
Poly-ᵞ-glutamic acid siRNA Dendrigraft poly-L-lysine [90]
Heparin Plasmid DNA Cationic glycopolymer (Tr4) [91]
Poly-ᵞ-glutamic acid siRNA Polyethylenimine [92]

Volume 2 Issue 3 (2023) 11 https://doi.org/10.36922/td.1356