Gaolin Liang

In Situ Nanofiber Formation Blocks AXL and GAS6 Binding to Suppress Ovarian Cancer Development

AbstractAnexelekto (AXL) is an attractive molecular target for ovarian cancer therapy because of its important role in ovarian cancer initiation and progression. To date, several AXL inhibitors have entered clinical trials for the treatment of ovarian cancer. However, the disadvantages of low AXL affinity and severe off‐target toxicity of these inhibitors limit their further clinical applications. Herein, by rational design of a nonapeptide derivative Nap‐Phe‐Phe‐Glu‐Ile‐Arg‐Leu‐Arg‐Phe‐Lys (Nap‐IR), a strategy of in situ nanofiber formation is proposed to suppress ovarian cancer growth. After administration, Nap‐IR specifically targets overexpressed AXL on ovarian cancer cell membranes and undergoes a receptor‐instructed nanoparticle‐to‐nanofiber transition. In vivo and in vitro experiments demonstrate that in situ formed Nap‐IR nanofibers efficiently induce apoptosis of ovarian cancer cells by blocking AXL activation and disrupting subsequent downstream signaling events. Remarkably, Nap‐IR can synergistically enhance the anticancer effect of cisplatin against HO8910 ovarian tumors. It is anticipated that the Nap‐IR can be applied in clinical ovarian cancer therapy in the near future.

β-Galactosidase-activated near-infrared AIEgen for ovarian cancer imaging in vivo

Near-infrared (NIR) aggregation induced-emission luminogens (AIEgens) circumvent the noisome aggregation-caused quenching (ACQ) effect in physiological milieu, thus holding high promise for real-time and sensitive imaging of biomarkers in vivo. β-Galactosidase (β-Gal) is a biomarker for primary ovarian carcinoma, but current AIEgens for β-Gal sensing display emissions in the visible region and have not been applied in vivo. We herein propose an NIR AIEgen QM-TPA-Gal and applied it for imaging β-Gal activity in vitro and in ovarian tumor model. After being internalized by ovarian cancer cells (e.g., SKOV3), the hydrophilic nonfluorescent QM-TPA-Gal undergoes hydrolyzation by β-Gal to yield hydrophobic QM-TPA-OH, which subsequently aggregates into nanoparticles to turn NIR fluorescence "on" through the AIE mechanism. In vitro experimental results indicate that QM-TPA-Gal has a sensitive and selective response to β-Gal with a limit of detection (LOD) of 0.21 U/mL. Molecular docking simulation confirms that QM-TPA-Gal has a good binding ability with β-Gal to allow efficient hydrolysis. Furthermore, QM-TPA-Gal is successfully applied for β-Gal imaging in SKOV3 cell and SKOV3-bearing living mouse models. It is anticipated that QM-TPA-Gal could be applied for early diagnosis of ovarian cancers or other β-Gal-associated diseases in near future.

Salt‐Inducible Kinase 2‐Triggered Release of Its Inhibitor from Hydrogel to Suppress Ovarian Cancer Metastasis

AbstractSalt‐inducible kinase 2 (SIK2) is a promising target for ovarian cancer therapy due to its critical role in tumorigenesis and progression. Currently available SIK2 inhibitors have shown remarkable therapeutic effects on ovarian cancers in preclinical studies. However, direct administration of the SIK2 inhibitors may bring significant off‐target effect, limiting their clinical applications. In this work, by rational design of a hydrogelator Nap‐Phe‐Phe‐Glu‐Glu‐Leu‐Tyr‐Arg‐Thr‐Gln‐Ser‐Ser‐Ser‐Asn‐Leu‐OH (Nap‐S) to coassemble a SIK2 inhibitor HG‐9‐91‐01 (HG), a SIK2‐responsive supramolecular hydrogel (Gel Nap‐S+HG) for local administration and SIK2‐responsive release of HG is reported to efficiently suppress ovarian cancer metastasis. Under the activation of SIK2 overexpressed in ovarian cancers, Nap‐S in the hydrogel is phosphorylated to yield hydrophilic Nap‐Phe‐Phe‐Glu‐Glu‐Leu‐Tyr‐Arg‐Thr‐Gln‐Ser(H2PO3)‐Ser‐Ser‐Asn‐Leu (Nap‐Sp), triggering the disassembly of the hydrogel and a responsive release of the inhibitor. Cell experiments indicate that sustained release of HG from Gel Nap‐S+HG induce a prominent therapeutic effect on cancer cells by inhibiting SIK2 and phosphorylation of their downstream signaling molecules. Animal experiments demonstrate that, compared with those tumor model mice treated with free HG, Gel Nap‐S+HG‐treatment mice show an enhanced inhibition on ovarian tumor growth and metastasis. It is anticipated that the Gel Nap‐S+HG can be applied for ovarian cancer therapy in clinic in the near future.