FTY720-induced enhancement of autophagy protects cells from FTY720 cytotoxicity in colorectal cancer

Fingolimod Inhibits C6 Rat Glioma Proliferation and Migration, Induces Sub-G1 Cell Cycle Arrest, Mitochondrial and Extrinsic Apoptosis In Vitro and Reduces Tumour Growth In Vivo

Glioblastoma multiforme (GBM), the most prevalent brain tumour, is universally fatal. GBM cells exhibit cell cycle disruption and treatment resistance, remarking an urgent need for newer treatments. Fingolimod, a sphingosine-1-phosphate receptor modulator, has been reported to have anti-cancer effects. This study investigated the therapeutic potentials of fingolimod in rat C6 cells and pursued the involved mechanism(s). Cell survival, proliferation, migration, and morphology of fingolimod-treated C6 cells were evaluated using MTT, soft-agar colony formation, wound-healing, and Giemsa staining assays. Apoptosis was investigated through acridine orange/ethidium bromide (AO/EB) and annexin V staining, and flow cytometry analysed the cell cycle. Quantitative reverse transcription PCR and western blotting were used to evaluate gene and protein expressions. An intracranial C6 rat model validated the anti-tumour effect of fingolimod. Fingolimod significantly reduced the survival and colonies of the C6 cells and delayed their gap closure. Cell shrinkage coupled with AO/EB and PI staining of the fingolimod-treated cells indicated apoptosis, subsequently confirmed by measuring the expression levels of the candidate genes involved in apoptosis and cell cycle, such as Bax/Bcl2, P53, Cytochrome C and Caspases 9/3, Fas, Fadd, Tnfrsf1a, Cdkn1a, and Ccnd1, at RNA and protein levels, indicating both extrinsic and mitochondrial apoptosis and cell cycle arrest at sub-G1 phase in fingolimod-treated cells. Furthermore, treating rats bearing intracranial C6 tumours with fingolimod led to significant suppression of intracranial tumour growth. Based on our findings, cell cycle arrest and apoptosis contribute to fingolimod antitumor effects.

Fingolimod alleviates type 2 diabetes associated cognitive decline by regulating autophagy and neuronal apoptosis via AMPK/mTOR pathway

This study aimed to reveal the role of fingolimod (FTY720) in mice with type 2 diabetes-associated cognitive decline and explore its potential neuroprotective mechanism. Mice were divided into five groups: normal control, normal control + FTY720 (1.0 mg/kg/day), type 2 diabetes mellitus, type 2 diabetes mellitus + low-dose FTY720 (0.5 mg/kg/day), and type 2 diabetes mellitus + high-dose FTY720 (1.0 mg/kg/day). Different doses of FTY720 were administered daily for 8 weeks after the induction of type 2 diabetes using a four-week high-fat diet feeding combined with continuous low-dose intraperitoneal injections of streptozotocin. After 8 weeks of treatment, the body weights and fasting blood glucose levels of mice from the five groups were compared. Morris water maze and new object recognition tests were used to evaluate cognitive function. Pathological changes in the hippocampal CA1 region were observed using haematoxylin-eosin and Nissl staining, and the ultrastructure of the hippocampal neurones was assessed using transmission electron microscopy. The expression levels of autophagy- and apoptosis-related proteins, such as LC3, Beclin-1, P62, Bax, and Bcl-2, in the mice hippocampus were detected by western blotting. Simultaneously, AMPK/mTOR signaling pathway proteins were detected to understand the potential mechanism. FTY720 had no significant effect on the body weight or fasting blood glucose levels in mice with type 2 diabetes. However, both FTY720 doses improved the cognitive function and hippocampal damage. In addition, the results suggested that FTY720 dramatically decreased P62 and Bax levels and increased LC3 II/LC3 I ratio, Beclin-1, and Bcl-2 expression in the hippocampus of type 2 diabetic mice. FTY720 also affected the expression of the AMPK/mTOR signaling pathway. Thus, FTY720 improved cognitive function and hippocampal pathological changes in type 2 diabetic mice without affecting fasting blood glucose levels. Our results show that FTY720 may exert neuroprotective effects in vivo by enhancing hippocampal autophagy and inhibiting apoptosis via the AMPK/mTOR signaling pathway.

Therapeutic Potential for Sphingolipids in Inflammatory Bowel Disease and Colorectal Cancer

Inflammatory bowel disease (IBD), characterized by chronic inflammation in the intestinal tract, increases the risk for the development of colorectal cancer (CRC). Sphingolipids, which have been implicated in IBD and CRC, are a class of bioactive lipids that regulate cell signaling, differentiation, apoptosis, inflammation, and survival. The balance between ceramide (Cer), the central sphingolipid involved in apoptosis and differentiation, and sphingosine-1-phosphate (S1P), a potent signaling molecule involved in proliferation and inflammation, is vital for the maintenance of normal cellular function. Altered sphingolipid metabolism has been implicated in IBD and CRC, with many studies highlighting the importance of S1P in inflammatory signaling and pro-survival pathways. A myriad of sphingolipid analogues, inhibitors, and modulators have been developed to target the sphingolipid metabolic pathway. In this review, the efficacy and therapeutic potential for modulation of sphingolipid metabolism in IBD and CRC will be discussed.

The Effects of Protein Phosphatase 2A Activation with Novel Tricyclic Sulfonamides on Hepatoblastoma

BACKGROUND

The tumor suppressor, protein phosphatase 2A (PP2A), is downregulated in hepatoblastoma. We aimed to examine the effects of two novel compounds of the tricyclic sulfonamide class, ATUX-3364 (3364) and ATUX-8385 (8385), designed to activate PP2A without causing immunosuppression, on human hepatoblastoma.

METHODS

An established human hepatoblastoma cell line, HuH6, and a human hepatoblastoma patient-derived xenograft, COA67, were treated with increasing doses of 3364 or 8385, and viability, proliferation, cell cycle and motility were investigated. Cancer cell stemness was evaluated by real-time PCR and tumorsphere forming ability. Effects on tumor growth were examined using a murine model.

RESULTS

Treatment with 3364 or 8385 significantly decreased viability, proliferation, cell cycle progression and motility in HuH6 and COA67 cells. Both compounds significantly decreased stemness as demonstrated by decreased abundance of OCT4, NANOG, and SOX2 mRNA. The ability of COA67 to form tumorspheres, another sign of cancer cell stemness, was significantly diminished by 3364 and 8385. Treatment with 3364 resulted in decreased tumor growth in vivo.

CONCLUSION

Novel PP2A activators, 3364 and 8385, decreased hepatoblastoma proliferation, viability, and cancer cell stemness in vitro. Animals treated with 3364 had decreased tumor growth. These data provide evidence for further investigation of PP2A activating compounds as hepatoblastoma therapeutics.

Modulating Fingolimod (FTY720) Anti-SARS-CoV-2 Activity Using a PLGA-Based Drug Delivery System

COVID-19 has resulted in more than 490 million people being infected worldwide, with over 6 million deaths by April 05th, 2022. Even though the development of safe vaccine options is an important step to reduce viral transmission and disease progression, COVID-19 cases will continue to occur, and for those cases, efficient treatment remains to be developed. Here, a drug repurposing strategy using nanotechnology is explored to develop a therapy for COVID-19 treatment. Nanoparticles (NPs) based on PLGA for fingolimod (FTY720) encapsulation show a size of ∼150 nm and high drug entrapment (∼90%). The NP (NP@FTY720) can control FTY720 release in a pH-dependent manner. Cytotoxicity assays using different cell lines show that NP@FTY720 displays less toxicity than the free drug. Flow cytometry and confocal microscopy reveal that NPs are actively internalized mostly through caveolin-mediated endocytosis and macropinocytosis pathways and co-localized with lysosomes. Finally, NP@FTY720 not only exhibits anti-SARS-CoV-2 activity at non-cytotoxic concentrations, but its biological potential for viral infection inhibition is nearly 70 times higher than that of free drug treatment. Based on these findings, the combination of drug repurposing and nanotechnology as NP@FTY720 is presented for the first time and represents a promising frontline in the fight against COVID-19.

The inhibition of autophagy by spautin boosts the anticancer activity of fingolimod in multidrug-resistant hepatocellular carcinoma

The contribution of autophagy to drug resistance has been studied in several cancers. However, there is no clear evidence about the role of autophagy in the resistance to chemotherapy in cancers, such as hepatocellular carcinoma (HCC). HCC is characterized by a poor prognosis and limited therapeutic options. Moreover, the emergence of multidrug-resistance (MDR) hinders successful treatment. Therefore, understanding how autophagy is regulated in resistant HCC is essential for sensitizing this malignancy to chemotherapy. This work demonstrated that basal and induced autophagy differ between parental and resistant Hep3B cells. In optimum growth conditions, the basal level of autophagy was low in resistant Hep3B (Hep3B-R) cells compared to the wild-type Hep3B (Hep3B-P) cells. However, in metabolic or therapeutic stress conditions, the rate of autophagy flux was much faster in the resistant cells. The work also confirmed the pro-survival function of autophagy in HCC. Besides, it demonstrated that the autophagy inhibitor, spautin, acted synergistically with fingolimod (FTY720) to promote cell death. The combination treatment resulted in superior reactive oxygen species (ROS) production and significant induction of apoptosis. In addition, spautin potentiated the effect of FTY720 against cell survival pathways like the Akt and ERK. Interestingly, the results indicated that Hep3B-R cells were more sensitive to autophagy inhibition than their parental counterparts. Collectively, this work revealed that combining spautin with chemotherapeutic agents that induce cytoprotective autophagy such as FTY720 is a promising approach to overcome MDR in HCC.

Molecular Pharmacology and Novel Potential Therapeutic Applications of Fingolimod

Fingolimod is a well-tolerated, highly effective disease-modifying therapy successfully utilized in the management of multiple sclerosis. The active metabolite, fingolimod-phosphate, acts on sphingosine-1-phosphate receptors (S1PRs) to bring about an array of pharmacological effects. While being initially recognized as a novel agent that can profoundly reduce T-cell numbers in circulation and the CNS, thereby suppressing inflammation and MS, there is now rapidly increasing knowledge on its previously unrecognized molecular and potential therapeutic effects in diverse pathological conditions. In addition to exerting inhibitory effects on sphingolipid pathway enzymes, fingolimod also inhibits histone deacetylases, transient receptor potential cation channel subfamily M member 7 (TRMP7), cytosolic phospholipase A2α (cPLA2α), reduces lysophosphatidic acid (LPA) plasma levels, and activates protein phosphatase 2A (PP2A). Furthermore, fingolimod induces apoptosis, autophagy, cell cycle arrest, epigenetic regulations, macrophages M1/M2 shift and enhances BDNF expression. According to recent evidence, fingolimod modulates a range of other molecular pathways deeply rooted in disease initiation or progression. Experimental reports have firmly associated the drug with potentially beneficial therapeutic effects in immunomodulatory diseases, CNS injuries, and diseases including Alzheimer's disease (AD), Parkinson's disease (PD), epilepsy, and even cancer. Attractive pharmacological effects, relative safety, favorable pharmacokinetics, and positive experimental data have collectively led to its testing in clinical trials. Based on the recent reports, fingolimod may soon find its way as an adjunct therapy in various disparate pathological conditions. This review summarizes the up-to-date knowledge about molecular pharmacology and potential therapeutic uses of fingolimod.

Lysosome‑targeted drug combination induces multiple organelle dysfunctions and non‑canonical death in pancreatic cancer cells

Pancreatic cancer is one of the leading causes of cancer-related mortality and has the lowest 5-year survival rate. Therefore, novel strategies are urgently required to treat pancreatic cancer. Pancreatic ductal adenocarcinoma (PDAC) cells rely on enhanced lysosomal function for survival and proliferation to facilitate the degradation of contents accumulated via autophagy and macropinocytosis. Previously, we have reported that the combination of epidermal growth factor receptor/HER2 inhibitor lapatinib and sphingosine analog fingolimod (FTY720) confers a significant cytostatic effect in lung cancer cells. In the present study, the combined effects of these drugs on PDAC cell lines, BxPC-3, KP-4, PANC-1 and MIA PaCa-2, were examined. It was observed that FTY720 enhanced the lapatinib-induced cytotoxic effect and caused non-canonical and lysosome-dependent death in PDAC cells. Lapatinib and FTY720 induced lysosomal swelling and inhibited lysosomal acidification. Combination treatment with lapatinib and FTY720 increased lysosomal membrane permeability, induced mitochondrial depolarization, induced endoplasmic reticulum stress and disturbed intracellular calcium homeostasis. Additionally, the cytotoxic effect of lapatinib was enhanced by hydroxychloroquine or the CDK4/6 inhibitor abemaciclib, both of which induce lysosomal dysfunction. Collectively, these results indicated that the lysosome-targeted drug combination induces multiple organelle dysfunction and exerts a marked cytotoxic effect in PDAC cells.

Targeting Sphingolipids for Cancer Therapy

Sphingolipids are an extensive class of lipids with different functions in the cell, ranging from proliferation to cell death. Sphingolipids are modified in multiple cancers and are responsible for tumor proliferation, progression, and metastasis. Several inhibitors or activators of sphingolipid signaling, such as fenretinide, safingol, ABC294640, ceramide nanoliposomes (CNLs), SKI-II, α-galactosylceramide, fingolimod, and sonepcizumab, have been described. The objective of this review was to analyze the results from preclinical and clinical trials of these drugs for the treatment of cancer. Sphingolipid-targeting drugs have been tested alone or in combination with chemotherapy, exhibiting antitumor activity alone and in synergism with chemotherapy in vitro and in vivo. As a consequence of treatments, the most frequent mechanism of cell death is apoptosis, followed by autophagy. Aslthough all these drugs have produced good results in preclinical studies of multiple cancers, the outcomes of clinical trials have not been similar. The most effective drugs are fenretinide and α-galactosylceramide (α-GalCer). In contrast, minor adverse effects restricted to a few subjects and hepatic toxicity have been observed in clinical trials of ABC294640 and safingol, respectively. In the case of CNLs, SKI-II, fingolimod and sonepcizumab there are some limitations and absence of enough clinical studies to demonstrate a benefit. The effectiveness or lack of a major therapeutic effect of sphingolipid modulation by some drugs as a cancer therapy and other aspects related to their mechanism of action are discussed in this review.

Differential Expression of the Sphingolipid Pathway Is Associated with Sensitivity to the PP2A Activator FTY720 in Colorectal Cancer Cell Lines

Protein phosphatase 2A (PP2A) is a ubiquitously expressed intracellular serine/threonine phosphatase. Deregulation of PP2A is a common event associated with adenocarcinomas of the colon and rectum. We have previously shown that breast cancer cell lines are sensitive to the PP2A activator FTY720, and that sensitivity is predicted by high Aurora kinase A (AURKA) mRNA expression. In this study, we hypothesized that high relative AURKA expression could predict sensitivity to FTY720-induced apoptosis in colorectal cancer (CRC). The CRC cell lines NCI H716, COLO320DM, DLD-1, SW480, and HT-29 show a high relative AURKA expression as compared to LS411N, T84, HCT116, SW48, and LOVO. Following viability assays, LS411N, T84, HCT116, and SW480 were shown to be sensitive to FTY720, whereas DLD-1 and HT-29 were non-sensitive. Hence, AURKA mRNA expression does not predict sensitivity to FTY720 in CRC cell lines. Differentially expressed genes (DEGs) were obtained by comparing the sensitive CRC cell lines (LS411N and HCT116) against the non-sensitive (HT-29 and DLD-1). We found that 253 genes were significantly altered in expression, and upregulation of CERS4, PPP2R2C, GNAZ, PRKCG, BCL2, MAPK12, and MAPK11 suggests the involvement of the sphingolipid signaling pathway, known to be activated by phosphorylated-FTY720. In conclusion, although AURKA expression did not predict sensitivity to FTY720, it is evident that specific CRC cell lines are sensitive to 5 µM FTY720, potentially because of the differential expression of genes involved in the sphingolipid pathway.

FTY720 inhibits colon cancer cell survival and increases their sensitivity to gemcitabine through the miR-494/MST1 pathway

BACKGROUND

Colon cancer ranks 5th in both incidence and mortality among malignant tumors in China. Chemotherapy is the main treatment method. Studies have shown that immunosuppressive agent FTY720 has a certain inhibitory effect on cancer cell proliferation. Inhibitors combined with chemotherapy drugs can improve the therapeutic effect of cancer. In this study, immunosuppressive agent FTY720 and gemcitabine were used together to treat colon cancer cells, and the role of miR-494/mammalian Ste20-like kinase 1 (MST1) in the proliferation and apoptosis of colon cancer cells was explored, with an aim to provide a new treatment for colon cancer.

AIM

To investigate the effects of FTY720 and gemcitabine on the survival and apoptosis of colon cancer cells and the potential molecular mechanisms involved.

METHODS

Colon cancer SW1116 cells were treated with gemcitabine at concentrations of 0.0001 μg/mL, 0.001 μg/mL, 0.01 μg/mL, 0.1 μg/mL, and 1 μg/mL and FTY720 at concentrations of 2.5 μmol/L, 5 μmol/L, 7.5 μmol/L, 10 μmol/L, and 12.5 μmol/L. CCK8 assay and flow cytometry were applied to detect the survival rate and apoptosis rate of SW1116 cells. Quantitative real-time polymerase chain reaction was used to measure the levels of miR-494 and MST1 mRNA. Western blot was carried out to detect the expression levels of MST1, p21, and Caspase-3 proteins. Dual-luciferase reporter assay was performed to verify the relationship between miR-494 and MST1.

RESULTS

Gemcitabine and FTY720 reduced the survival rate of colon carcinoma SW1116 cells in a concentration dependent manner. According to the results, 0.1 μg/mL gemcitabine and 10 μmol/L FTY720 with an inhibition rate of about 50% were selected for subsequent experiments. Gemcitabine and FTY720 both inhibited cell survival and promoted cell apoptosis, and their combined use was better than the single use. Overexpression of miR-494 reversed the effects of FTY720 and gemcitabine on survival and apoptosis in SW1116 cells. MiR-494 targeted and regulated MST1. Inhibition of MST1 reversed the effects of FTY720 and gemcitabine on the survival and apoptosis in SW1116 cells.

CONCLUSION

FTY720 and gemcitabine inhibit SW1116 cell survival and promote apoptosis through the miR-494/MST1 pathway. The combination of FTY720 and gemcitabine has more significantly inhibitory effects on the survival and apoptosis of SW1116 cells.

Sphingolipids and Mitochondrial Dynamic

For decades, sphingolipids have been related to several biological functions such as immune system regulation, cell survival, and proliferation. Recently, it has been reported that sphingolipids could be biomarkers in cancer and in other human disorders such as metabolic diseases. This is evidenced by the biological complexity of the sphingolipids associated with cell type-specific signaling and diverse sphingolipids molecules. As mitochondria dynamics have serious implications in homeostasis, in the present review, we focused on the relationship between sphingolipids, mainly ceramides and sphingosine-1-phosphate, and mitochondrial dynamics directed by fission, fusion, and mitophagy. There is evidence that the balances of ceramides (C18 and C16) and S1P, as well as the location of specific ceramide synthases in mitochondria, have roles in mitophagy and fission with an impact on cell fate and metabolism. However, signaling pathways controlling the sphingolipids metabolism and their location in mitochondria need to be better understood in order to propose new interventions and therapeutic strategies.

Rapamycin and FTY720 Alleviate Atherosclerosis by Cross Talk of Macrophage Polarization and Autophagy

Foam cell formation and macrophage polarization are involved in the pathologic development of atherosclerosis, one of the most important human diseases affecting large and medium artery walls. This study was designed to assess the effects of rapamycin and FTY720 (fingolimod) on macrophages and foam cells. Mouse peritoneal macrophages were collected and treated with rapamycin and FTY720 to study autophagy, polarization, and lipid accumulation. Next, foam cells were formed by oxidizing low-density lipoprotein to observe changes in lipid accumulation, autophagy, and polarization in rapamycin-treated or FTY720-treated foam cells. Lastly, foam cells that had been treated with rapamycin and FTY720 were evaluated for sphingosine 1-phosphate receptor (S1prs) expression. Autophagy microtubule-associated protein 1 light chain 3- (LC3-) II was increased, and classically activated macrophage phenotype markers interleukin- (IL-) 6, cyclooxygenase-2 (COX2), and inducible nitric oxide synthase (iNOS) were increased, whereas alternatively activated macrophage phenotype markers transforming growth factor- (TGF-) β, arginase 1 (Arg1), and mannose receptor C-type 1 (Mrc1) were decreased by rapamycin in peritoneal macrophages. LC3-II was also obviously enhanced, though polarization markers were unchanged in rapamycin-treated foam cells. Moreover, lipid accumulation was inhibited in rapamycin-treated macrophage cells but was unchanged in rapamycin-treated foam cells. For FTY720, LC3-II did not change, whereas TGF-β, Arg1 and Mrc1 were augmented, and IL-6 was suppressed in macrophages. However, LC3-II was increased, and TGF-β, ARG1 and MRC1 were strikingly augmented, whereas IL-6, COX2 and iNOS could be suppressed in foam cells. Furthermore, lipid accumulation was alleviated in FTY720-treated foam cells. Additionally, S1pr1 was markedly decreased in foam cells (P < .05); S1pr2, S1pr3, S1pr4 and S1pr5 were unchanged in rapamycin-treated foam cells. In FTY720-treated foam cells, S1pr3 and S1pr4 were decreased, and S1pr1, S1pr2 and S1pr5 were unchanged. Therefore, we deduced that rapamycin stimulated classically activated macrophages and supressed early atherosclerosis. Rapamycin may also stabilize artery plaques by preventing apoptosis and S1PR1 in advanced atherosclerosis. FTY720 allowed transformation of foam cells into alternatively activated macrophages through the autophagy pathway to alleviate advanced atherosclerosis.

FTY720 Decreases Tumorigenesis in Group 3 Medulloblastoma Patient-Derived Xenografts

Group 3 tumors account for 28% of medulloblastomas and have the worst prognosis. FTY720, an immunosuppressant currently approved for treatment of multiple sclerosis, has shown antitumor effects in several human cancer cell lines. We hypothesized that treatment with FTY720 (fingolimod) would decrease tumorigenicity in medulloblastoma patient-derived xenografts (PDXs). Three Group 3 medulloblastoma PDXs (D341, D384 and D425) were utilized. Expression of PP2A and its endogenous inhibitors I2PP2A and CIP2A was detected by immunohistochemistry and immunoblotting. PP2A activation was measured via phosphatase activation kit. Cell viability, proliferation, migration and invasion assays were performed after treatment with FTY720. Cell cycle analysis was completed using flow cytometry. A flank model using D425 human medulloblastoma PDX cells was used to assess the in vivo effects of FTY720. FTY720 activated PP2A and led to decreased medulloblastoma PDX cell viability, proliferation, migration and invasion and G1 cell cycle arrest in all three PDXs. FTY720 treatment of mice bearing D425 medulloblastoma PDX tumors resulted in a significant decrease in tumor growth compared to vehicle treated animals. FTY720 decreased viability, proliferation, and motility in Group 3 medulloblastoma PDX cells and significantly decreased tumor growth in vivo. These results suggest that FTY720 should be investigated further as a potential therapeutic agent for medulloblastoma.

Targeted co-delivery of Beclin 1 siRNA and FTY720 to hepatocellular carcinoma by calcium phosphate nanoparticles for enhanced anticancer efficacy

Purpose

FTY720, known as fingolimod, is a new immunosuppressive agent with effective anticancer properties. Although it was recently confirmed that FTY720 inhibits cancer cell proliferation, FTY720 can also induce protective autophagy and reduce cytotoxicity. Blocking autophagy with Beclin 1 siRNA after treatment with FTY720 promotes apoptosis. The objective of this study was to enhance the anticancer effect of FTY720 in hepatocellular carcinoma (HCC) by targeted co-delivery of FTY720 and Beclin 1 siRNA using calcium phosphate (CaP) nanoparticles (NPs).

Materials and methods

First, the siRNA was encapsulated within the CaP core. To form an asymmetric lipid bilayer structure, we then used an anionic lipid for the inner leaflet and a cationic lipid for the outer leaflet; after removing chloroform by rotary evaporation, these lipids were dispersed in a saline solution with FTY720. The NPs were analyzed by transmission electron microscopy, dynamic light scattering and ultraviolet–visible spectrophotometry. Cancer cell viability and cell death were analyzed by MTT assays, fluorescence-activated cell sorting analysis and Western blotting. In addition, the in vivo effects of the NPs were investigated using an athymic nude mouse subcutaneous transplantation tumor model.

Results

When the CaP NPs, called LCP-II NPs, were loaded with FTY720 and siRNA, they exhibited the expected size and were internalized by cells. These NPs were stable in systemic circulation. Furthermore, co-delivery of FTY720 and Beclin 1 siRNA significantly increased cytotoxicity in vitro and in vivo compared with that caused by treatment with the free drug alone.

Conclusion

The CaP NP system can be further developed for co-delivery of FTY720 and Beclin 1 siRNA to treat HCC, enhancing the anticancer efficacy of FTY720. Our findings provide a new insight into HCC treatment with co-delivered small molecules and siRNA, and these results can be readily translated into cancer clinical trials.