Enhanced anticancer activity and circumvention of resistance mechanisms by novel polymeric/ phospholipidic nanocarriers of doxorubicin

Synthesis of novel indole-thiazolidinone hybrid structures as promising scaffold with anticancer potential

A series of novel indole-azolidinone hybrids has been synthesized via Knoevenagel reaction of 5-fluoro-3-formyl-1H-indole-2-carboxylic acid methyl ester and some azolidinones differing in heteroatoms in positions 1, 2 and 4. Their anticancer activity in vitro was screened towards MCF-7 (breast cancer), HCT116 (colon cancer), HepG2 (hepatoma), HeLa (cervical cancer), A549 (lung cancer), WM793 (melanoma) and THP-1 (leukemia) cell lines, and a highly active 5-fluoro-3-(4-oxo-2-thioxothiazolidin-5-ylidenemethyl)-1H-indole-2-carboxylic acid methyl ester (3a) was identified and subjected to in-depth investigation of cytotoxicity mechanisms. This compound was found to possess the highest cytotoxic action towards tumor cells comparing with the action of other derivatives (1, 3b, 3c, 3d, 3e). Compound 3a exhibited toxicity toward MCF-7, HCT116, and A549, HepG2 cancer cells, while the non-malignant cells (human keratinocytes of HaCaT line and murine embryonic fibroblasts of Balb/c 3T3 line) possessed moderate sensitivity to it. The compound 3a induced apoptosis in studied tumor cells via caspase 3-, PARP1-, and Bax-dependent mechanisms; however, it did not affect the G1/S transition in HepG2 cells. The compound 3a impaired nuclear DNA in HepG2, HCT116, and MCF-7 cells without intercalating this biomolecule, but much less DNA damage events were induced by 3a in normal Balb/c 3T3 fibroblasts compared with HepG2 carcinoma cells. Thus, 5-fluoro-3-(4-oxo-2-thioxothiazolidin-5-ylidenemethyl)-1H-indole-2-carboxylic acid methyl ester 3a was shown to trigger DNA damage and induce apoptosis of human tumor cells and it might be considered as an anticancer agent perspective for in-depth studies.

Enhanced Proapoptotic Effects of Water Dispersed Complexes of 4-Thiazolidinone-Based Chemotherapeutics with a PEG-Containing Polymeric Nanocarrier

AIM

To study whether water formulation of the complex of 4-thiazolidinone derivatives with a PEG-containing polymeric nanocarrier enhances their pro-apoptotic action towards rat glioma C6 cells.

METHODS

Mechanisms of antineoplastic effects of 4-thiazolidinone derivatives were investigated in vitro with rat glioma C6 cells. Cell nativity, cell cycling pattern, and Annexin V expression were evaluated and DNA damage was estimated by DNA comet analysis. A novel water-based formulation of 4-thiazolidinone derivatives complexed with a polymeric nanocarrier was utilized for enhancing pro-apoptotic action towards C6 cells.

RESULTS

The studied 4-thiazolidinone derivatives use apoptosis mechanisms for killing rat glioma C6 cells, as confirmed by FACS analysis of these cells in pre-G1 stage, the appearance of Annexin V positive C6 cells, and an increased number of DNA comets of higher classes. Complexation of the studied compounds with a PEG-containing polymeric nanocarrier significantly increased pro-apoptotic effects in rat glioma C6 cells measured by all methods mentioned above.

CONCLUSION

Complexation of 4-thiazolidinone derivatives with a PEG-containing polymeric nanocarrier provided them with water solubility and enhanced pro-apoptotic effects in rat glioma C6 cells.

Comb-like PEG-containing polymeric composition as low toxic drug nanocarrier

BACKGROUND

Development of biocompatible multifunctional polymeric drug carriers is crucial in modern pharmaceutics aimed to create "smart" drugs. The high potential of the PEGylated comb-like polymeric nanocarrier (PNC) in delivering both traditional and experimental drugs to tumor cells in vitro and in vivo has been demonstrated previously. In the present study, we investigated the general toxicity of polyethylene glycol (PEG) processed with both covalent and non-covalent attachments of PEG to compose a comb-like polymer that behaves like a simple chain of n monomers decorated with swollen side chains. The PNC possesses properties of a water-soluble surfactant containing methyl-terminated PEG side branches in some monomer units attached covalently to the carbon chain backbone.

RESULTS

We have demonstrated that the synthesized PNC possesses weak toxic effects toward human leukemia cells (HL-60 and Jurkat lines), as well as toward hepatocellular (HepG2), colon (HCT116) and breast (MCF-7) tumor cell lines. Additionally, after a long period (20 days) of intraperitoneal administration, the PNC had no significant toxic effects in laboratory white mice (470 mg/kg body mass in 1 ml) and Wistar rats (440 mg/kg body mass in 10 ml).

CONCLUSION

The developed PNC we studied can be qualified as a compound of grade 4 toxicity (low toxicity substance). The reduced toxicity of this PNC in combination with its improved bioavailability and previously detected capability to enhance cytotoxicity toward tumor cells in vitro and potential tumor treatment effects in vivo suggests its potential as a safe drug delivery platform for treating various diseases, especially cancer.

Cytotoxicity and apoptosis enhancement in breast and cervical cancer cells upon coadministration of mitomycin C and essential oils in nanoemulsion formulations

The present study aimed to solubilize the antineoplastic agent, mitomycin C (MMC), in two nanoemulsions (NEs) consisting of different essential oils (ginger (Gi) and frankincense (Fr)) in order to examine their anticancer activities on the HeLa cervical cancer cells and MCF-7 breast cancer cells. The two NEs-based Gi and Fr oil were produced by a high-pressure homogenization technique followed by solubilizing of the MMC in both NE formulas. The produced formulas were physically characterized by zetasizer and were applied on HeLa and MCF-7 cells at various concentrations for 24 h. The cytotoxicity assays were performed in vitro, using MTT assay, Coomassie blue staining for cellular morphology evaluation, and DAPI fluorescent staining for molecular cell death assessment. The average droplet diameters of the blank NEs have markedly increased and the charges of the droplets were significantly reversed when MMC was loaded. The potential cytotoxicity of the blank and combined formulas on HeLa and MCF-7 cells were dose-dependent and significantly greater than the toxicities of the free MMC. Among the MMC-loaded NE formulas, Fr-MMC has endured the nuclear apoptosis in HeLa cells at a lower concentration and reported the least % of florescence uptake compared to Gi-MMC. In contrast, the combination formula, Gi-MMC, has the strongest apoptotic effect on the MCF-7 cell line since it has the least % florescence uptake compared to the other formulations. Mixing MMC with Gi-NE and Fr-NE has considerably improved its cytotoxicity on the MCF-7 and HeLa cells.

Co-delivery of vincristine and quercetin by nanocarriers for lymphoma combination chemotherapy

PURPOSE

Chemotherapy is the current standard treatment for Non-Hodgkin's lymphoma (NHL). Combination therapy is emerging as an important strategy for a better long-term prognosis with decreased side effects, maximized therapeutic effect. The aim of this study is to deliver vincristine (VCR) and quercetin (QU) with synergistic drug ratios through lipid-polymeric nanocarriers (LPNs) for the lymphoma combination chemotherapy METHODS: In this present study, we constructed VCR and QU dual-loaded LPNs (VCR/QU LPNs) and investigated their antitumor efficacy in vitro cell culture models and a tumor xenograft mouse model.

RESULTS

The formulated VCR/QU LPNs exhibited nano-size, negative zeta potential with sustained release profile in vitro. The dual drug loaded LPNs exhibited the best antitumor efficacy in vitro and in vivo.

CONCLUSION

It could be concluded that VCR/QU LPNs can combine the efficiency of these two drugs, bring about synergistic effect. Co-encapsulation of VCR and QN in the same LPNs has potential as a novel therapeutic approach to overcome chemo-resistant lymphoma.

Novel transferrin modified and doxorubicin loaded Pluronic 85/lipid-polymeric nanoparticles for the treatment of leukemia: In vitro and in vivo therapeutic effect evaluation

PURPOSE

Childhood leukemia is a common malignant disease in children. Doxorubicin (DOX) was widely used for the treatment of leukemia. However, severe toxic side effects and drug resistance are the major limitations of DOX. Nanocarriers offer the opportunity to overcome these drawbacks, there are many attempts to enhance the activity of DOX against drug resistance. This study aimed to develop a novel transferrin (Tf) modified and doxorubicin (DOX) loaded Pluronic 85/lipid-polymeric nanoparticles for the treatment of leukemia.

METHODS

In this study, a novel targeted ligand: transferrin-polyethylene glycol-oleic acid (Tf-PEG-OA) was synthesized. Tf modified and DOX loaded Pluronic 85/lipid-polymeric nanoparticles (Tf-DOX P85/LPNs) were prepared via the self-assembly of PLGA, P85, stearic acid and Tf-PEG-OA using the nanoprecipitation method. The physicochemical properties of LPNs were characterized. In vitro and in vivo anti-tumor efficacy of LPNs was evaluated in human promyelocytic leukemia cell line (HL-60 cells) and DOX resistance HL-60 cell line (HL-60/DOX cells) including the relevant animal models.

RESULTS

Tf-DOX P85/LPNs displayed strong anti-tumor ability on both HL-60 cells and HL-60/DOX cells than other formulations used as contrast. Also, in HL-60/DOX bearing animal models, Tf-DOX P85/LPNs exhibited the highest efficiency as well as the lowest systemic toxicity.

CONCLUSION

The results indicated that Tf P85/LPNs is a promising platform to enhance efficacy, reduce toxicity and overcome drug resistance of DOX for the treatment of leukemia.

Hurdles in selection process of nanodelivery systems for multidrug-resistant cancer

PURPOSE

Most of the nanomedicines for treatment of multidrug-resistant cancer do not reach Phase III trials and many are terminated or withdrawn or are in an indeterminate state since long without any study results being presented. Extensive perusal of nanomedicine development research revealed that one of the critical aspects influencing clinical outcomes and which requires diligent scrutiny is selection process of nanodelivery system.

METHODS

Research papers and articles published on development of nanodelivery systems for treatment of multidrug-resistant cancer were analyzed. Observations and conclusions noted by these researchers which might shed some light on poor clinical performance of nanocarriers were collated and summarized under observation section. Further research articles were studied to find possible solutions which may be applied to these particular problems for resolving them. The inferences of these findings were composed in Result section.

RESULT

Plausible solutions for the observed obstacles were noted as examples of novel formulations that can yield the following: better in vivo imaging, precise targeting and dosing of a specific site and specific cell type in a particular cancer, modulation of tumor surroundings, intonation of systemic effects and high reproducibility.

CONCLUSION

The angle of approach to the development of best nanosystem for a specific type of tumor needs to be spun around. Some of these changes can be brought about by individual scientists, some need to be established by collated efforts of scientists globally and some await advent of better technologies. Regardless of the stratagem, it can be said decisively that the schematics of development phase need rethinking.

Integrated traditional Chinese and western medicine modulator for overcoming the multidrug resistance with carbon nanotubes

GA/Dox/P-gp Ab-CNTs, integrated specific targeting, P-gp inhibitor and chemotherapeutic agent, could represent a promising modulator for overcoming tumor MDR.