Downregulation of FAPP2 gene induces cell autophagy and inhibits PI3K/AKT/mTOR pathway in T-cell acute lymphoblastic leukemia

Unveiling autophagy complexity in leukemia: The molecular landscape and possible interactions with apoptosis and ferroptosis

Autophagy is a self-digestion multistep process in which causes the homeostasis through degradation of macromolecules and damaged organelles. The autophagy-mediated tumor progression regulation has been a critical point in recent years, revealing the function of this process in reduction or acceleration of carcinogenesis. Leukemia is a haematological malignancy in which abnormal expansion of hematopoietic cells occurs. The current and conventional therapies from chemotherapy to cell transplantation have failed to appropriately treat the leukemia patients. Among the mechanisms dysregulated in leukemia, autophagy is a prominent one in which can regulate the hallmarks of this tumor. The protective autophagy inhibits apoptosis and ferroptosis in leukemia, while toxic autophagy accelerates cell death. The proliferation and invasion of tumor cells are tightly regulated by the autophagy. The direction of regulation depends on the function of autophagy that is protective or lethal. The protective autophagy accelerates chemoresistance and radio-resistsance. The non-coding RNAs, histone transferases and other pathways such as PI3K/Akt/mTOR are among the regulators of autophagy in leukemia progression. The pharmacological intervention for the inhibition or induction of autophagy by the compounds including sesamine, tanshinone IIA and other synthetic compounds can chance progression of leukemia.

Targeted delivery of AZD5363 to T-cell acute lymphocytic leukemia by mSiO2-Au nanovehicles

T-cell acute lymphocytic leukemia (T-ALL) is the most common cancer in children, with a low survival rate because of drug resistance and a high recurrence rate. Targeted delivery of chemotherapy drugs can reduce their side effects and improve their efficacy. The abnormality of phosphatidylinositol-3-kinase/protein kinase B/ mammalian target of rapamycin (PI3K/Akt/mTOR) pathway plays a key role in T-ALL occurrence. AZD5363 is a selective Akt inhibitor with promising therapeutic potential for tumors encoded by the PI3K/Akt/mTOR pathway. However, the toxicity and side effects have limited its application in treating T-ALL. This study aimed to design a delivery system for targeting AZD5363 to T-ALL by sgc8c aptamer designed as mesoporous silica (mSiO2) decorated with Au nanoparticles. The cell-specific targeting and cytotoxicity of mSiO2-Au-AZD5363-Apt were investigated. The mSiO2-Au nanovehicles were found feasible for AZD5363 delivery, with high loading efficiency and pH-responsive release in the acidic lysosome. More importantly, mSiO2-Au-AZD5363-Apt nanovehicles could specifically recognize and enter T-ALL cells in vitro and in vivo, effectively inhibiting the proliferation of CCRF-CEM cells. In conclusion, mSiO2-Au-AZD5363-Apt provided an effective therapeutic method for the targeted treatment of T-ALL.

Pump proton inhibitors display anti-tumour potential in glioma

OBJECTIVES

Glioma is one of the most aggressive brain tumours with poor overall survival despite advanced technology in surgical resection, chemotherapy and radiation. Progression and recurrence are the hinge causes of low survival. Our aim is to explain the concrete mechanism in the proliferation and progression of tumours based on tumour microenvironment (TME). The main purpose is to illustrate the mechanism of proton pump inhibitors (PPIs) in affecting acidity, hypoxia, oxidative stress, inflammatory response and autophagy based on the TME to induce apoptosis and enhance the sensitivity of chemoradiotherapy.

FINDINGS

TME is the main medium for tumour growth and progression. Acidity, hypoxia, inflammatory response, autophagy, angiogenesis and so on are the main causes of tumour progress. PPIs, as a common clinical drug to inhibit gastric acid secretion, have the advantages of fast onset, long action time and small adverse reactions. Nowadays, several kinds of literature highlight the potential of PPIs in inhibiting tumour progression. However, long-term use of PPIs alone also has obvious side effects. Therefore, till now, how to apply PPIs to promote the effect of radio-chemotherapy and find the concrete dose and concentration of combined use are novel challenges.

CONCLUSIONS

PPIs display the potential in enhancing the sensitivity of chemoradiotherapy to defend against glioma based on TME. In the clinic, it is also necessary to explore specific concentrations and dosages in synthetic applications.