Efficacy of edelfosine lipid nanoparticles in breast cancer cells

Breast cancer is a heterogeneous group of neoplasms predominantly originating in the terminal duct lobular units. It represents the leading cause of cancer death in women and the survival frequencies for patients at advanced stages of the disease remain low. New treatment options need to be researched to improve these rates. The anti-tumor ether lipid edelfosine (ET) is the prototype of a novel generation of promising anticancer drugs. However, it presents several drawbacks for its use in cancer therapy, including gastrointestinal and hemolytic toxicity and low oral bioavailability. To overcome these obstacles, ET was encapsulated in Precirol ATO 5 lipid nanoparticles (ET-LN), and its anti-tumor potential was in vitro tested in breast cancer. The formulated ET-LN were more effective in inhibiting cell proliferation and notably decreased cell viability, showing that the cytotoxic effect of ET was considerably enhanced when ET was encapsulated. In addition, ET and ET-LN were able to promote cell cycle arrest at G1 phase. Moreover, although both treatments provoked an apoptotic effect in a time-dependent manner, such anti-tumor effects were noticeably improved with ET-LN treatment. Therefore, our results indicate that encapsulating ET in LN played an essential role in improving the efficacy of the drug

Edelfosine lipid nanoparticles overcome MDR in K-562 leukemia cells by caspaseindependent mechanism

The anti-tumor ether lipid edelfosine is the prototype of a novel generation of promising anticancer drugs that has been shown to be an effective anti-tumor agent in numerous malignancies. However, several cancer types display resistance to different anti-tumor compounds due to multi-drug resistance (MDR), which is a major drawback in anticancer therapy. The leukemic cell line K-562 shows resistance to edelfosine, which can be overcome by the use of nanotechnology. The present paper describes the rate and mechanism of internalization of free and nano-encapsulated edelfosine. The molecular mechanisms underlying this cell death is described in the present paper by characterization of several molecules implied in the apoptotic and autophagic pathways (PARP, LC3IIB, Caspases-3, - 9 and -7) and the pattern of expression is compared with cell induction in a sensitive cell line HL-60. The results showed different internalization patterns in both cells. Clathrin and lipid raftmediated endocytosis were observable in edelfosine uptake whereas these mechanism were not visible in the uptake of lipid nanoparticles which might suffer phagocytosis and macropinocytosis. Both treatments endorsed caspase-mediated apoptosis in HL-60 cells but this cell death was not observed in K-562 cells. Moreover, an important increase in autophagic vesicles was visible in K-562 cells. Thus, this mechanism might be implicated in the overcoming of K-562 resistance to the treatment by lipid nanoparticles

In vitro intestinal co-culture cell model to evaluate intestinal absorption of edelfosine lipid nanoparticles

Nanotechnology is providing a new therapeutic paradigm by enhancing drug efficacy and preventing side-effects. Edelfosine is a synthetic ether lipid analogue of platelet activating factor with high antitumor activity. The encapsulation of this potent antitumor drug in lipid nanoparticles increases its oral bioavailability; moreover, it prevents the hemolytic and gastrointestinal side-effects of the free drug. The literature points towards lymphatic absorption of lipid nanoparticles after oral administration, and previous in vitro and in vivo studies stress the protection against toxicity that these nanosystems provide. The present study is intended to assess the permeability of lipid nanoparticles across the intestinal barrier. Caco-2 monoculture and Caco-2/Raji co-culture were used as in vitro models of enterocytes and Microfold cells respectively. Results showed that free drug is internalized and possibly metabolized in enterocytes. These results do not correlate with those observed in vivo when edelfosine-lipid nanoparticles were administered orally in mice, which suggests that the microfold model is not a good model to study the absorption of edelfosine-lipid nanoparticles across the intestinal barrier in vitro

In vivo biodistribution of edelfosine-loaded lipid nanoparticles radiolabeled with Technetium-99 m: Comparison of administration routes in mice

Edelfosine (ET) is a potent antitumor agent but causes severe side effects that have limited its use in clinical practice. For this reason, nanoencapsulation in lipid nanoparticles (LNs) is advantageous as it protects from ET side-effects. Interestingly, previous studies showed the efficacy of LNs containing ET in various types of tumor. In this paper, biodistribution studies of nanoencapsulated ET, administered by three routes (oral, intravenous (IV) and intraperitoneal (IP)), were tested in order to select the optimal route of administration. To do this, ET-LNs were labeled with Technetium-99 m (99mTc) and administered by the oral, IV and IP route in mice. IV admin- istration of the radiolabeled LNs led to fast elimination from the blood circulation and increased accumulation in reticulo-endothelial (RES) organs, while their oral administration could not provide any evidence on their bio- distribution since large radiocomplexes were formed in the presence of gastrointestinal fluids. However, when the LNs were administered by the IP route they could access the systemic circulation and provided more constant blood ET-LN levels compared to the IV route. These findings suggest that the IP route can be used to sustain the level of drug in the blood and avoid accumulation in RES organs

Edelfosine lipid nanosystems overcome drug resistance in leukemic cell lines

Although current therapies have improved leukemia survival rates, adverse drug effects and relapse are frequent. Encapsulation of edelfosine (ET) in lipid nanoparticles (LN) improves its oral bioavailability and decreases its toxicity. Here we evaluated the efficacy of ET-LN in myeloid leukemia cell lines. Drug-loaded LN were as effective as free ET in sensitive leukemia cell lines. Moreover, the encapsulated drug overcame the resistance of the K562 cell line to the drug. LN containing ET might be used as a promising drug delivery system in leukemia due to their capacity to overcome the in vivo pitfalls of the free drug and their efficacy in vitro in leukemia cell lines

Lipid nanoparticles for cancer therapy: state of the art and future prospects

Introduction: Cancer is a leading cause of death worldwide and it is estimated that deaths from this disease will rise to over 11 million in 2030. Most cases of cancer can be cured with surgery, radiotherapy or chemotherapy if they are detected at an early stage. However, current cancer therapies are commonly associated with undesirable side effects, as most chemotherapy treatments are cytotoxic and present poor tumor targeting. Areas covered: Lipid nanoparticles (LN) are one of the most promising options in this field. LN are made up of biodegradable generally recognized as safe (GRAS) lipids, their formulation includes different techniques, and most are easily scalable to industrial manufacture. LN overcome the limitations imposed by the need for intravenous administration, as they are mainly absorbed via the lymphatic system when they are administered orally, which improves drug bioavailability. Furthermore, depending on their composition, LN present the ability to cross the blood-brain barrier, thus opening up the possibility of targeting brain tumors. Expert opinion: The drawbacks of chemotherapeutic agents make it necessary to invest in research to find safer and more effective therapies. Nanotechnology has opened the door to new therapeutic options through the design of formulations that include a wide range of materials and formulations at the nanometer range, which improve drug efficacy through direct or indirect tumor targeting, increased bioavailability and diminished toxicity

Alquil-lysophospholipids and cancer: development of lipid nanoparticles for oral administration and preclinical studies

Current leukemia treatments are generally associated to severe side-effects and relapse is frequent in adults. Edelfosine (ET) is the prototype of a family of antitumor drugs with potent antitumor effects against several cancer types. However, the use of ET in clinic remains limited due to ET side-effects. Nanomedicine has achieved great success in the medicine field and lipid nanoparticles (LN) have been widely used in cancer due to their benefits in therapy. The present work hypothesized that edelfosine lipid nanoparticles (ET-LN) might be an effective therapy against leukemia. The in vitro studies in leukemia cells showed that the antitumor effect of the drug is preserved after its encapsulation into LN. Moreover, ET-LN were able to overcome drug resistance in case of resistant cells (K-562). Endocytosis studies revealed that ET and ET-LN are internalized by different uptake mechanisms in sensitive and resistant cells. Studies of molecular mechanisms implicated in cell death showed that ET and ET-LN promoted similar caspase-mediated apoptosis cell death in sensitive HL-60 cells, whereas the induction of this cell death mechanism was not observed in resistant K-562 cells. In this cell line, ET and ET-LN endorsed a high induction of autophagic vesicles. As the induction of autophagy was demonstrated for both treatments, it is not possible to directly correlate K-562 sensitivity to ET-LN with autophagy cell death. As these nanosystems are designed for oral delivery, the next step of this work aimed to evaluate the intestinal absorption of ET and ET-LN after oral administration. Surprisingly, these results evidenced a likely metabolic process of ET in enterocytes. In case of ET-LN, ET might be protected from this metabolic process when it is encapsulated into LN. Besides, the developed Caco-2/Raji co-culture model did not show translocation of ET-LN from the apical to the basal compartment. At this point, these results could be explained as the limitations of in vitro experiments to describe drugs in vivo behaviours. Afterwards, and bearing in mind the toxicity of antitumor drugs, we aimed to confirm the benefits that LN might provide in the toxicological profile of ET. Results confirm that LN provide a protective effect against the toxicity of the free drug, as LN prevented from the severe acute toxicity of higher dose of ET. These results were very interesting because they demonstrate not only that ET-LN are safe even at high doses but also that LN are a safe vehicle and could allow the administration of other antitumor agents by the oral route. Finally, a preliminary efficacy study was performed in a xenogeneic mouse model of human acute lymphoblastic leukemia. Radiolabeling studies led to the conclusion that intraperitoneal (i.p.) route might be more adequate to administer ET-LN that intravenous route. Efficacy studies were performed by i.p. route. Animals were administered a dose that is considered safe by the oral route but that showed to be toxic for the animals treated with ET, and ET-LN. Nevertheless, efficacy studies were encouraging as both ET and ET-LN were able to decrease percentage of human leukemia cells in mice with respect to control group. To conclude, the general hypothesis of the work has been confirmed as in vitro results in leukemia cells showed similar o greater efficacy of the ET-LN over the free drug. Besides, even in the case of similar efficacy, LN would offer advantages over the free drug in terms of protection against ET toxicity. Indeed, toxicity studies demonstrated that LN are a safe vehicle for the administration of antitumor agents by the oral route. Finally, in vivo efficacy studies showed promising preliminary results

Alquil-lysophospholipids and cancer: development of lipid nanoparticles for oral administration and preclinical studies

Current leukemia treatments are generally associated to severe side-effects and relapse is frequent in adults. Edelfosine (ET) is the prototype of a family of antitumor drugs with potent antitumor effects against several cancer types. However, the use of ET in clinic remains limited due to ET side-effects. Nanomedicine has achieved great success in the medicine field and lipid nanoparticles (LN) have been widely used in cancer due to their benefits in therapy. The present work hypothesized that edelfosine lipid nanoparticles (ET-LN) might be an effective therapy against leukemia. The in vitro studies in leukemia cells showed that the antitumor effect of the drug is preserved after its encapsulation into LN. Moreover, ET-LN were able to overcome drug resistance in case of resistant cells (K-562). Endocytosis studies revealed that ET and ET-LN are internalized by different uptake mechanisms in sensitive and resistant cells. Studies of molecular mechanisms implicated in cell death showed that ET and ET-LN promoted similar caspase-mediated apoptosis cell death in sensitive HL-60 cells, whereas the induction of this cell death mechanism was not observed in resistant K-562 cells. In this cell line, ET and ET-LN endorsed a high induction of autophagic vesicles. As the induction of autophagy was demonstrated for both treatments, it is not possible to directly correlate K-562 sensitivity to ET-LN with autophagy cell death. As these nanosystems are designed for oral delivery, the next step of this work aimed to evaluate the intestinal absorption of ET and ET-LN after oral administration. Surprisingly, these results evidenced a likely metabolic process of ET in enterocytes. In case of ET-LN, ET might be protected from this metabolic process when it is encapsulated into LN. Besides, the developed Caco-2/Raji co-culture model did not show translocation of ET-LN from the apical to the basal compartment. At this point, these results could be explained as the limitations of in vitro experiments to describe drugs in vivo behaviours. Afterwards, and bearing in mind the toxicity of antitumor drugs, we aimed to confirm the benefits that LN might provide in the toxicological profile of ET. Results confirm that LN provide a protective effect against the toxicity of the free drug, as LN prevented from the severe acute toxicity of higher dose of ET. These results were very interesting because they demonstrate not only that ET-LN are safe even at high doses but also that LN are a safe vehicle and could allow the administration of other antitumor agents by the oral route. Finally, a preliminary efficacy study was performed in a xenogeneic mouse model of human acute lymphoblastic leukemia. Radiolabeling studies led to the conclusion that intraperitoneal (i.p.) route might be more adequate to administer ET-LN that intravenous route. Efficacy studies were performed by i.p. route. Animals were administered a dose that is considered safe by the oral route but that showed to be toxic for the animals treated with ET, and ET-LN. Nevertheless, efficacy studies were encouraging as both ET and ET-LN were able to decrease percentage of human leukemia cells in mice with respect to control group. To conclude, the general hypothesis of the work has been confirmed as in vitro results in leukemia cells showed similar o greater efficacy of the ET-LN over the free drug. Besides, even in the case of similar efficacy, LN would offer advantages over the free drug in terms of protection against ET toxicity. Indeed, toxicity studies demonstrated that LN are a safe vehicle for the administration of antitumor agents by the oral route. Finally, in vivo efficacy studies showed promising preliminary results

Edelfosine lipid nanosystems overcome drug resistance in leukemic cell lines

Although current therapies have improved leukemia survival rates, adverse drug effects and relapse are frequent. Encapsulation of edelfosine (ET) in lipid nanoparticles (LN) improves its oral bioavailability and decreases its toxicity. Here we evaluated the efficacy of ET-LN in myeloid leukemia cell lines. Drug-loaded LN were as effective as free ET in sensitive leukemia cell lines. Moreover, the encapsulated drug overcame the resistance of the K562 cell line to the drug. LN containing ET might be used as a promising drug delivery system in leukemia due to their capacity to overcome the in vivo pitfalls of the free drug and their efficacy in vitro in leukemia cell lines

In vivo biodistribution of edelfosine-loaded lipid nanoparticles radiolabeled with Technetium-99 m: Comparison of administration routes in mice

Edelfosine (ET) is a potent antitumor agent but causes severe side effects that have limited its use in clinical practice. For this reason, nanoencapsulation in lipid nanoparticles (LNs) is advantageous as it protects from ET side-effects. Interestingly, previous studies showed the efficacy of LNs containing ET in various types of tumor. In this paper, biodistribution studies of nanoencapsulated ET, administered by three routes (oral, intravenous (IV) and intraperitoneal (IP)), were tested in order to select the optimal route of administration. To do this, ET-LNs were labeled with Technetium-99 m (99mTc) and administered by the oral, IV and IP route in mice. IV admin- istration of the radiolabeled LNs led to fast elimination from the blood circulation and increased accumulation in reticulo-endothelial (RES) organs, while their oral administration could not provide any evidence on their bio- distribution since large radiocomplexes were formed in the presence of gastrointestinal fluids. However, when the LNs were administered by the IP route they could access the systemic circulation and provided more constant blood ET-LN levels compared to the IV route. These findings suggest that the IP route can be used to sustain the level of drug in the blood and avoid accumulation in RES organs