Comparison of anesthetic agents on otoacoustic emissions in children: propofol vs ketamine

Propofol inhibits tumor angiogenesis through targeting VEGF/VEGFR and mTOR/eIF4E signaling

Propofol, a commonly used intravenous anesthetic in tumor surgery, has recently garnered attention for its anti-cancer activity. We previously demonstrated that propofol inhibits migration and invasion of esophageal squamous cell carcinoma cells. However, the effects of propofol in tumor angiogenesis are inconclusive. The current study investigated the effects of propofol on the biological functions of lung cancer associated endothelial cells (LC-EC) and colon cancer associated endothelial cells (CC-EC) that represent in vitro tumor angiogenesis. We showed that propofol inhibited tubular structure formation of both LC-EC and CC-EC, particularly the early stages of angiogenesis. In addition, propofol inhibited migration, adhesion, proliferation, and survival of tumor associated endothelial cells. Mechanism studies revealed that propofol disrupted tumor angiogenesis microenvironment via suppressing expression and secretion of multiple pro-angiogenic factors by tumor cells. Propofol also inhibited VEGF/VEGFR2-and mTOR/eIF4E-mediated signaling pathways in endothelial cells. Our findings demonstrate the inhibitory effects of propofol on tumor angiogenesis and support the anti-cancer properties of propofol. Our work provides preclinical evidence into the potential mechanisms by which propofol may negatively affect tumor growth and metastasis.

Propofol inhibits biological functions of leukaemia stem and differentiated cells through suppressing Wnt/β-catenin and Akt/mTOR

The biological roles of intravenous anaesthetic propofol in cancer have been shown by various studies using cancer cell lines that represent differentiated cancer cells. However, the activities of propofol in cancer stem cells have not been elucidated. In this work, we examined the effects and mechanisms of propofol on acute myeloid leukaemia (AML) differentiated and CD34⁺ CD38^- stem cells. We found that propofol inhibited growth, differentiation and self-renewal capabilities of AML stem cells regardless of cellular origin and genetic profiling. In addition, propofol inhibited the growth of AML differentiated cells. Propofol significantly induced apoptosis of AML differentiated but not CD34⁺ CD38^- stem cells. We further found that propofol significantly augmented the efficacy of AML standard therapeutic drugs. Consistent with the previous findings, we showed that propofol suppressed the Akt/mTOR pathway in AML cells. We also found that propofol inhibited pathways important for stem cell maintenance and self-renewal, such as Wnt/β-catenin. Overexpression of constitutively active Akt partially reversed the inhibitory effects of propofol in AML differentiated cells. Stabilization of β-catenin using genetic and pharmacological approaches also partially rescued the inhibitory effects of propofol in AML differentiated and stem cells. Our work shows that propofol targets leukaemia cells at all stages of development, in a cell type-specific manner. Inhibition of both Akt/mTOR and Wnt/β-catenin is required for the action of propofol in AML. Our findings also highlight the activities of propofol on cancer stem cells.

Propofol enhances BCR-ABL TKIs' inhibitory effects in chronic myeloid leukemia through Akt/mTOR suppression

Background

The anti-cancer activities of intravenous anesthetic drug propofol have been demonstrated in various types of cancers but not in chronic myeloid leukemia (CML).

Methods

We systematically examined the effect of propofol and its combination with BCR-ABL tyrosine kinase inhibitors (TKIs) in CML cell lines, patient progenitor cells and mouse xenograft model. We analyzed propofol’s underlying mechanism focusing on survival pathway in CML cells.

Results

We show that propofol alone is active in inhibiting proliferation and inducing apoptosis in KBM-7, KU812 and K562 cells, and acts synergistically with imatinib or dasatinib, in in vitro cell culture system and in vivo xenograft model. In addition, propofol is more effective in inducing apoptosis and inhibiting colony formation in CML CD34 progenitor cells than normal bone marrow (NBM) counterparts. Combination of propofol and dasatinib significantly eliminates CML CD34 without affecting NBM CD34 cells. We further demonstrate that propofol suppresses phosphorylation of Akt, mTOR, S6 and 4EBP1 in K562. Overexpression of constitutively active Akt significantly reverses the inhibitory effects of propofol in K562, confirm that propofol acts on CML cells via inhibition of Akt/mTOR. Interestingly, the levels of p-Akt, p-mTOR and p-S6 are lower in cells treated with combination of propofol and imatinib than cells treated with propofol or imatinib alone, suggesting that propofol augments BCR-ABL TKI’s inhibitory effect via suppressing Akt/mTOR pathway.

Conclusion

Our work shows that propofol can be repurposed to for CML treatment. Our findings highlight the therapeutic value of Akt/mTOR in overcoming resistance to BCR-ABL TKI treatment in CML.

Electronic supplementary material

The online version of this article (10.1186/s12871-017-0423-2) contains supplementary material, which is available to authorized users.