Polymeric nanocarriers: A promising tool for early diagnosis and efficient treatment of colorectal cancer

Abstract

Background: Colorectal cancer (CRC) is the third most prevalent type of cancer for incidence and second for mortality worldwide. Late diagnosis and inconvenient and expensive current diagnostic tools largely contribute to the progress of the disease. The use of chemotherapy in the management of CRC significantly reduces tumor growth, metastasis, and morbidity rates. However, poor solubility, low cellular uptake, nonspecific distribution, multiple drug resistance and unwanted adverse effects are still among the major drawbacks of chemotherapy that limit its clinical significance in the treatment of CRC. Owing to their remarkable advantages over conventional therapies, the use of nanotechnology-based delivery systems especially polymeric nanocarriers (PNCs) has revolutionized many fields including disease diagnosis and drug delivery.

Aim of review: In this review, we shed the light on the current status of using PNCs in the diagnosis and treatment of CRC with a special focus on targeting strategies, surface modifications and safety concerns for different types of PNCs in colonic cancer delivery.

Key scientific concepts of review: The review explores the current progress on the use of PNCs in the diagnosis and treatment of CRC with a special focus on the role of PNCs in improvement of cellular uptake, drug targeting and co-delivery of chemotherapeutic agents. Possible toxicity and biocompatibility issues related to the use of PNCs and imitations and future recommendation for the use of those smart carriers in the diagnosis and treatment of CRC are also discussed.

Keywords: Colorectal cancer; Early diagnosis; Polymeric nanocarriers; Superior therapeutic outcomes; Targeted delivery.

Graphical abstract

Fig. 1

Graphical representation for CRC progression showing the different stages of tumor development and associated modifiable risk factors.

Fig. 2

Examples of the three divisions of nanomaterials used in therapeutic management of different types of cancer.

Fig. 3

Treatment of HCT-116 cell lines with TBP-Ps-Dox. A) Schematic diagram showing the accumulation and retention and cellular uptake of Tf@TBP-Ps-Dox in HCT-116 cells over-expressing transferrin receptor. B) Dependence of HCT-116 cell viability on concentrations of functionalized Ps with significant decrease in IC50 compared to Dox-loaded polymersome (Ps-Dox) and Dox-loaded liposomes (Lipo-Dox); C) confocal laser scanning microscope images showing intracellular release of Dox from Tf@TBP-Ps-Dox and Ps-Dox (Scale Bar: 25 μm) and D) In vivo imaging of HCT-116 tumor-bearing mice after intravenous injection of Cy5-labeled Tf@TBP-Ps and Ps. The orange circles represent the tumor regions. Adapted with permission from Wei et al. 2020, Elsevier .

Fig. 4

Representation of the activity of CUR/miR145-Pr NCs in SW480 CRC cells showing A) a schematic diagram of CUR/miR145-Pr NCs B cell proliferation after treatment of with different nanocapsules; B) the Interaction of CUR and miR-145- loaded protamine nanocapsules with SW480 CRC cells; and C) confocal laser scanning microscope images showing of cells treated with CUR- (green channel) and Cy5-miR- (red channel) loaded into Pr NCs. Adapted with permission from Reimondez-Troitiño et al. 2019, Elsevier .