Peripheral serotonin is involved in tumorigenesis and induces a pro-proliferative effect in hepatocellular carcinoma (HCC) cells; however, the intracellular mechanisms by which serotonin exerts a mitogenic effect remain unclear. In this research, we examined whether FOXO3a, a transcription factor at the interface of crucial cellular processes, plays a role downstream of serotonin in HCC cells.

Pancreatic ductal adenocarcinoma rapidly acquires resistance to chemotherapy, remaining a fatal disease. Immunotherapy is one of the breakthroughs in cancer treatment, which includes immune checkpoint inhibitors, chimeric antigen receptor T-cell immunotherapy, and neoantigen vaccines. However, immunotherapy has not achieved satisfactory results in the treatment of pancreatic cancer. Immunogenic death comprises proinflammatory cell death, which provides a way to enhance tumor immunogenicity and promote an immune response in solid tumors. Herein, an ionic liquid ablation agent (LAA), synthesized from choline and geranic acid, which triggers necrosis-induced immunotherapy by remodeling an immunosuppressive "cold" tumor to an immune activated "hot" tumor is described. The results indicate that LAA-treated tumor cells can enhance immunogenicity, inducing dendritic cell maturation, macrophage M1 polarization, and cytotoxic T lymphocyte infiltration. The results of the present study provide a novel strategy for solid tumor immunotherapy.

One of the main obstacles in tumor therapy is multiple drug resistance (MDR) and an underlying mechanism of MDR is up-regulation of the transmembrane ATP-binding cassette (ABC) transporter proteins, especially P-glycoprotein (P-gp). In the synergistic treatment of siRNA and anti-cancer drug doxorubicin, it is crucial that both the siRNA and doxorubicin are simultaneously delivered to the tumor cells and the siRNA can fleetly down-regulate P-g before doxorubicin inactivates the P-gp and is pumped out. Herein, a type of micelles comprising a polycationic PEI-CyD shell to condense the siRNA and hydrophobic core to package doxorubicin is reported. The structure of the polymer is determined by (1)H NMR, FT-IR, DSC, and XRD and the micelles are characterized by DLS, 2D-NOESY NMR, and TEM to study the self-assembly of the micelles with siRNA and drugs. In vitro studies demonstrate controlled release and temporal enhancement of the therapeutic efficacy of P-gp siRNA and doxorubicin. Release of siRNA down-regulates the mRNA and protein levels of P-gp in the MCF-7/ADR cell lines effectively and the accumulated doxorubicin facilitates apoptosis of the cells to reverse MDR. Moreover, in vivo research reveals that the siRNA and doxorubicin loaded micelles induce tumor cell apoptosis and inhibit the growth of MDR tumor. The western blotting and RT-PCR results illustrate that the synergistic treatment of siRNA and doxorubicin leads to efficient reduction of the P-gp expression as well as cell apoptotic induction in MDR tumors at a small dosage of 0.5 mg/kg. The micelles have large clinical potential in drug/RNAi synergistic treatment via restoration of the chemosensitivity in MDR cancer therapy.

A new redox-sensitive poly(ethylene glycol) (PEG)-based gene vector specially designed to target fibroblast growth factor receptors (FGFRs) was developed by host-guest supramolecular complexation. The new vector was designed as follows: 1) A host segment was consisted of β-cyclodextrin-crosslinked low molecular polyethylenimine (PEI) conjugated with MC11 peptide (MQLPLATGGGC) that can target FGFRs, being termed as MC11-PEI-β-cyclodextrin (MPC); 2) A guest segment is consisted of PEG and adamantyl group linked by a disulfide bond, the adamantyl-SS-PEG (Ad-SS-PEG); and 3) PEGylation of MPC by supramolecular complexation between MPC and Ad-SS-PEG to generate MPC/Ad-SS-PEG polycation, where the PEG chains can stabilize the DNA polyplexes extracellularly but can be readily cleavable intracellularly. It was found that the MPC/Ad-SS-PEG complexes could efficiently condense pDNA into nanoparticles around 100-200 nm, and were able to effectively stabilize polyplexes against salt- or BSA-induced aggregation. The MPC/Ad-SS-PEG polyplexes were more readily to dissociate with the aid of heparin in the presence of 5 mm DTT. In vitro gene transfection and cytotoxicity experiments in different carcinoma cell lines expressing FGFRs showed that MPC/Ad-SS-PEG could mediate significantly higher transfection efficiency than MPC complexed with adamantyl-PEG (MPC/Ad-PEG), which has no disulfide linkage and is non-PEG-detachable. Furthermore, confocal laser scanning microscopy study indicated that MPC/Ad-SS-PEG polyplexes could mediate much more efficient endosomal escape than stably shield MPC/Ad-PEG polyplexes at 12 h post-transfection. Importantly, MPC/Ad-SS-PEG was also able to efficiently mediate tumor-targeted gene delivery in the tumor-bearing mouse model after systemic injection in vivo. These results suggest that the MPC/Ad-SS-PEG systems could be a safe and efficient non-viral vector for FGFR-mediated targeted gene delivery for cancer gene therapy.

Malignancies treated by insoluble targeted agents show low dose exposure and therapeutic responses, therefore easily develop drug resistance. Nanoparticle-modified drugs might disrupt chemoresistance by increasing dose exposure and altering resistance pathways, as administrated via the intravenous route to maximize efficacy. Herein, we proposed a self-assembled nanocapsulation strategy to construct a nanocomplex with multiarm polymer and novel dendrimer series (MAP-mG3) for encapsulating insoluble inhibitors by nucleotide lock. MAP-mG3 delivering the mammalian target of rapamycin (mTOR) inhibitor OSI-027 (MAP-mG3/OSI-027) showed higher loading capacity, enhanced solubility, controlled release, and increased intracellular tumoral accumulation. MAP-mG3/OSI-027, more efficiently than the free targeted agents, attenuated mTOR phosphorylation and inhibited growth of pancreatic cancer cells. In addition, MAP-mG3/OSI-027 reverted chemoresistance to OSI-027 in drug resistance pancreatic cancer by increasing intracellular dose exposure, as well as regulating ABCB1 expression and compensatory pathways. The optimized nanocapsulation design provides an effective strategy to engineer and reactivate insoluble targeted agents for chemoresistant applications.

Hepatolithiasis, featuring high incidence, severe symptoms, and common recurrence, poses a heavy disease burden. Endoscopic management provides an opportunity to cure hepatolithiasis, but fails to properly resolve biliary stricture without additional interventional techniques. An innovative approach towards endoscopic management of biliary stricture is required.

Purpose: Aiming to improve the drug loading capacity of dendritic nanoparticles and enhance delivery efficacy in drug-resistant cancer, we developed and optimized a more advanced dendritic, redox-responsive, supramolecular (Dr.S) system for intravenous RAD001 administration. Materials and methods: The Dr.S system was engineered by linking 3rd generation polyamidoamine dendrimers (G3 PAMAM) with 8-arm polyethylene glycol (PEG) to encapsulate a molecular targeted agent RAD001. The drug-loading capacity was measured by ultraviolet-visible spectrophotometry. In vitro release behavior was determined with a two-compartment model, and the in vivo distribution pattern was tracked by Cy5.5 fluorescence. The therapeutic effect of Dr.S/RAD001 was evaluated in RAD001-resistant cancer cells and tumor-bearing nude mice, respectively. Results: The Dr.S system encapsulating RAD001 with a loading efficiency of 10.6% formed a core-shell structure, by shifting hydrophobic PAMAM/RAD001 components towards inner space and exposing the hydrophilic PEG on the surface. The Dr.S/RAD001 system could respond to a lysis-mimicking reduction stimulus, and functionally release cargoes to facilitate tumor accumulation and cellular internalization. These features contributed to the enhanced anti-tumor activity of RAD001 in renal cancers in vitro and in vivo. The Dr.S/RAD001 system also reversed acquired RAD001-resistance by a 60-fold increase in tumor accumulation of the therapeutics. Conclusion: The functional Dr.S/RAD001 system enables lysis-triggered release of RAD001 to achieve better tumor accumulation, which helps overcome acquired drug resistance in renal cancers.