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Tumor Discovery Targeted drug delivery systems for the treatment of tumors

Figure 1. Schematic illustration of tumor targeting using drug-loaded nanocarriers through passive targeting approach.
Abbreviation: EPR: Enhanced permeability and retention.

overexpression has been linked to the development of
prostate cancer, leukemia, and melanoma. Both of these
target sites are preferred for active targeting, as they not
only restrict the supply of nutrients but also mediate the
[17]
disruption of tumor cells . Potential targets containing
specific proteins include B-cell maturation antigen and
lymphocyte antigens (relevant to hematological tumors),
G-protein coupled receptors (such as lysophosphatidic
acid, melanocortin, estrogen, angiotensin, vasopressin, and
gastrin-releasing peptides), cluster differentiation proteins,
interleukin receptors (associated with gliomas), and
prostate-specific membrane antigens [18,19] . Current tumor-
targeted drug delivery systems are designed to improve
blood perfusion, promote internalization, and facilitate
tissue infiltration by activating antitumor responses.

Figure 2. Ligand-bound receptor-mediated or active targeting of tumor 3.3. Cell-mediated targeting
cells.
The cell-mediated targeting approach is a highly
recommended strategy for anticancer drug delivery owing
in tumor cell metabolism and targeting suitability. The to its distinct virtues, including the precise direction of
overexpression of EGRF is associated with the development drugs to the target site, prolonged retention, and controlled
of various cancers, including those affecting the breast, drug release, all while minimizing immunogenicity and
stomach, and lungs. Consequently, EGRF becomes the cytotoxicity. This approach involves drug interactions
preferred active targeting site for the efficient delivery of with cell-mediated substrates, which encompass cytokines
anticancerous agents . In addition, folate receptors are (macrophage colony-stimulating factor), chemokines
[15]
highly expressed on the cell surface in epithelial, cervical, (monocyte chemotactic proteins), and cellular growth
ovarian, brain, lung, and colorectal cancer regions. factors (EGFR and vascular endothelial growth factor) .
[20]
Furthermore, myriad disorders and cancers, including the Drug carriers loaded with low molecular compounds,
pancreas, prostate, testicles, lymphomas, and sarcomas, genetic materials, proteins, and oncolytic viruses activate
exhibit elevated levels of folate receptors. Hence, folate T-lymphocytes, neutrophils, monocytes, macrophages,
receptors are the preferred choice for active targeting using and mesenchymal stem cells, all working together to target
various inorganic nanoparticles. tumor cells . Figure 3 depicts the process of cell-mediated
[21]
Furthermore, tumor progression is closely associated antitumor activity.
with the angiogenesis process, which is physiologically Various factors, including cell adhesion molecules and
regulated through the overexpression of vascular regulatory T cells, amplify cancer-associated responses,
EGFRs and integrins found in endothelial cells . This while cytotoxic T cells and natural killer (NK) cells
[16]

Volume 2 Issue 3 (2023) 4 https://doi.org/10.36922/td.1356