Lipid-polymer hybrid nanoparticle with cell-distinct drug release for treatment of stemness-derived resistant tumor

Drug resistance presents one of the major causes for the failure of cancer chemotherapy. Cancer stem-like cells (CSCs), a population of self-renewal cells with high tumorigenicity and innate chemoresistance, can survive conventional chemotherapy and generate increased resistance. Here, we develop a lipid-polymer hybrid nanoparticle for co-delivery and cell-distinct release of the differentiation-inducing agent, all-trans retinoic acid and the chemotherapeutic drug, doxorubicin to overcome the CSC-associated chemoresistance. The hybrid nanoparticles achieve differential release of the combined drugs in the CSCs and bulk tumor cells by responding to their specific intracellular signal variation. In the hypoxic CSCs, ATRA is released to induce differentiation of the CSCs, and in the differentiating CSCs with decreased chemoresistance, DOX is released upon elevation of reactive oxygen species to cause subsequent cell death. In the bulk tumor cells, the drugs are released synchronously upon the hypoxic and oxidative conditions to exert potent anticancer effect. This cell-distinct drug release enhances the synergistic therapeutic efficacy of ATRA and DOX with different anticancer mechanism. We show that treatment with the hybrid nanoparticle efficiently inhibit the tumor growth and metastasis of the CSC-enriched triple negative breast cancer in the mouse models.

Progress on cell differentiation and clinical application in neuroblastoma / 国际儿科学杂志

Neuroblastoma(NB)is the most common extracranial solid tumor in children.It is notable for highly heterogeneous and associated with tumor histologic classification and differentiation status, with ganglioneuroma representing fully mature and differentiated NB.Differentiation therapy reduces the adverse reactions caused by treatment without affecting normal cells and tissues by inducing the redifferentiation of NB cells, and has a good development prospect in the maintenance treatment of high-risk NB patients.Therefore, studying the key molecules and signaling pathways affecting NB differentiation is significant to further clarify the pathogenesis and improve the prognosis of neuroblastoma.This article reviews the important molecules related to NB cell differentiation, signaling pathways and the research progress of differentiation induction therapy.

AKT inhibitor Hu7691 induces differentiation of neuroblastoma cells

While neuroblastoma accounts for 15% of childhood tumor-related deaths, treatments against neuroblastoma remain scarce and mainly consist of cytotoxic chemotherapeutic drugs. Currently, maintenance therapy of differentiation induction is the standard of care for neuroblastoma patients in clinical, especially high-risk patients. However, differentiation therapy is not used as a first-line treatment for neuroblastoma due to low efficacy, unclear mechanism, and few drug options. Through compound library screening, we accidently found the potential differentiation-inducing effect of AKT inhibitor Hu7691. The protein kinase B (AKT) pathway is an important signaling pathway for regulating tumorigenesis and neural differentiation, yet the relation between the AKT pathway and neuroblastoma differentiation remains unclear. Here, we reveal the anti-proliferation and neurogenesis effect of Hu7691 on multiple neuroblastoma cell lines. Further evidence including neurites outgrowth, cell cycle arrest, and differentiation mRNA marker clarified the differentiation-inducing effect of Hu7691. Meanwhile, with the introduction of other AKT inhibitors, it is now clear that multiple AKT inhibitors can induce neuroblastoma differentiation. Furthermore, silencing AKT was found to have the effect of inducing neuroblastoma differentiation. Finally, confirmation of the therapeutic effects of Hu7691 is dependent on inducing differentiation in vivo, suggesting that Hu7691 is a potential molecule against neuroblastoma. Through this study, we not only define the key role of AKT in the progression of neuroblastoma differentiation but also provide potential drugs and key targets for the application of differentiation therapies for neuroblastoma clinically.

Dual-Blocking of PI3K and mTOR Improves Chemotherapeutic Effects on SW620 Human Colorectal Cancer Stem Cells by Inducing Differentiation

Cancer stem cells (CSCs) have tumor initiation, self-renewal, metastasis and chemo-resistance properties in various tumors including colorectal cancer. Targeting of CSCs may be essential to prevent relapse of tumors after chemotherapy. Phosphatidylinositol-3-kinase (PI3K) and mammalian target of rapamycin (mTOR) signals are central regulators of cell growth, proliferation, differentiation, and apoptosis. These pathways are related to colorectal tumorigenesis. This study focused on PI3K and mTOR pathways by inhibition which initiate differentiation of SW620 derived CSCs and investigated its effect on tumor progression. By using rapamycin, LY294002, and NVP-BEZ235, respectively, PI3K and mTOR signals were blocked independently or dually in colorectal CSCs. Colorectal CSCs gained their differentiation property and lost their stemness properties most significantly in dual-blocked CSCs. After treated with anti-cancer drug (paclitaxel) on the differentiated CSCs cell viability, self-renewal ability and differentiation status were analyzed. As a result dual-blocking group has most enhanced sensitivity for anti-cancer drug. Xenograft tumorigenesis assay by using immunodeficiency mice also shows that dual-inhibited group more effectively increased drug sensitivity and suppressed tumor growth compared to single-inhibited groups. Therefore it could have potent anti-cancer effects that dual-blocking of PI3K and mTOR induces differentiation and improves chemotherapeutic effects on SW620 human colorectal CSCs.