Recent advances in drug delivery systems for targeting cancer stem cells

Abstract

Cancer stem cells (CSCs) are a subpopulation of cancer cells with functions similar to those of normal stem cells. Although few in number, they are capable of self-renewal, unlimited proliferation, and multi-directional differentiation potential. In addition, CSCs have the ability to escape immune surveillance. Thus, they play an important role in the occurrence and development of tumors, and they are closely related to tumor invasion, metastasis, drug resistance, and recurrence after treatment. Therefore, specific targeting of CSCs may improve the efficiency of cancer therapy. A series of corresponding promising therapeutic strategies based on CSC targeting, such as the targeting of CSC niche, CSC signaling pathways, and CSC mitochondria, are currently under development. Given the rapid progression in this field and nanotechnology, drug delivery systems (DDSs) for CSC targeting are increasingly being developed. In this review, we summarize the advances in CSC-targeted DDSs. Furthermore, we highlight the latest developmental trends through the main line of CSC occurrence and development process; some considerations about the rationale, advantages, and limitations of different DDSs for CSC-targeted therapies were discussed.

Mitochondria: Insights into Crucial Features to Overcome Cancer Chemoresistance

“…An additional feature of this quite intricate scenario is cell heterogeneity in the bulk cancer; indeed, this permits the coexistence of diverse cell populations. Recent findings have outlined that cancer stem cells (CSCs) may be the pioneers of innate/acquired [ 4 , 5 , 6 ] conferring and spreading a resistance phenotype in the whole cancer pool and to other organs [ 3 , 4 , 7 , 8 ].…”

Nanoparticles for Targeted Drug Delivery to Cancer Stem Cells: A Review of Recent Advances

“… Dormancy state: CSCs enter dormancy to evade the attack by the immune system, awaiting new signals from the environment to re-enter the cell cycle [ 22 ]. Changes in morphology or biological function, such as the over-expression of anti-apoptotic proteins that block the cell from entering the type I apoptosis cycle [ 1 , 22 , 24 ]. Elevated expression of ATP-binding cassette (ABC) pumps and detoxifying enzymes to increase the drug’s efflux, which is considered to be an important mechanism for multi-drug resistance (MDR).…”

“…Changes in morphology or biological function, such as the over-expression of anti-apoptotic proteins that block the cell from entering the type I apoptosis cycle [ 1 , 22 , 24 ].…”

“…According to a report by the World Health Organization (WHO), cancer is recognized as the second leading cause of death in the world, with over 18 million cases and close to 10 million cancer-related mortalities in 2018 [ 1 ]. Due to the rapid pace of industrialization, it is anticipated that cancer mortality rates will nearly double by 2040 [ 2 ].…”

Resveratrol and Its Analogs: Potent Agents to Reverse Epithelial-to-Mesenchymal Transition in Tumors

“…Several critical EMT-inducing transcription factors (EMT-TFs), which include zinc-finger E-box binding homeobox 1 (ZEB1), ZEB2 (also known as SIp1), Snail1 (also known as Snail), Slug (also known as Snail2) and Twist-related protein 1 (Twist1; also known as Twist), have been demonstrated to play significant regulatory roles in the EMT program of cancer cells (74). In addition to activating the classic EMT traits and promoting tumor metastasis, EMT-TFs are associated with the induction to many other features, like maintenance of cancer stem cells (CSCs) and resistance to therapeutic drugs (75). CSCs are referred to tumor cells with the ability for self-renewal and recapitulation of the tumor heterogeneity (76).…”