1-2-dioleoyloxy-3-(trimethylammonium)propane and Colonic-Neoplasms

Regulfatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) are common immunosuppressive cells in the tumor microenvironment. These cells, through various mechanisms, inhibit antitumor immune responses and impede effective therapies. Therefore, designing an efficient protocol for inducing immune surveillance in tumors is highly recommended. Recently, nanoliposomes have provided broad-spectrum and state-of-the-art vehicles to deliver antigens or immune system compartments in immunotherapies. It has been shown that different lipids in the structure of liposomes and various liposomal formulations can affect immune responses in the tumor microenvironment. This study was aimed to evaluate the effects of four different liposomal formulations on MDSCs and Tregs in C26 tumor-bearing mice. To this end, after preparing liposomes, they were injected into tumor-inoculated mice and analyzed MDSC and Treg population and functions in spleen and tumor tissues. Results showed that 1,2-dioleoyl-3-trimethylammonium propane (DOTAP)-containing liposomes reduced MDSC population and activity in the spleen, but not tumor, compared with other groups significantly (p < 0.05 and p < 0.01, respectively). Moreover, DOTAP-containing liposomes reduced the expression of S100A8 and arginase-1 genes in splenic MDSCs (p < 0.05). In conclusion, we provided evidence that DOTAP-containing liposomes contributed to stimulating immune responses and provided a situation to inhibit immunosuppression in the tumor microenvironment.

Topics: Animals; Colonic Neoplasms; Liposomes; Mice; Myeloid-Derived Suppressor Cells; T-Lymphocytes, Regulatory; Tumor Microenvironment

As a therapeutic target for cancer treatment, HSP90 has been explored extensively. However, the significant side effects of the HSP90 inhibitor 17AAG have limited its clinical use.. In this study, we used hyaluronic acid (HA)-decorated DOTAP-PLGA hybrid nanoparticles (HA-DOTAP-PLGA NPs) as 17AAG-delivery carriers for targeted colon cancer therapy.. Different methods were used to characterize the successful fabrication of these hybrid PLGA NPs. Our results demonstrated that internalization of HA-NPs in colon cancer cells was governed by CD44receptor-mediated endocytosis. Annexin V-propidium iodide staining experiments revealed that cell apoptosis induced by HA-NPs-17AAG in colon cancer cells was more efficient than free 17AAG. In two animal models used to screen anticancer efficacy (Luc-HT29 subcutaneous xenograft and AOM/DSS-induced orthotopic tumor model), HA-NPs-17AAG significantly inhibited xenograft and orthotopic tumor growth, demonstrating HA-NPs-17AAG had much better therapeutic efficiency than free 17AAG. It is worth noting that great biocompatibility of HA-DOTAP-PLGA NPs was observed both in vitro and in vivo.. Our research offers a preclinical proof of concept for colon cancer therapy with DOTAP-PLGA NPs as a creative drug-delivery system.

Topics: Animals; Antineoplastic Agents; Apoptosis; Benzoquinones; Biocompatible Materials; Cell Line, Tumor; Colonic Neoplasms; Drug Delivery Systems; Endocytosis; Fatty Acids, Monounsaturated; Fluorescence; HSP90 Heat-Shock Proteins; Humans; Hyaluronan Receptors; Hyaluronic Acid; Lactams, Macrocyclic; Mice; Nanoparticles; Polylactic Acid-Polyglycolic Acid Copolymer; Quaternary Ammonium Compounds; Subcutaneous Tissue

Gene therapy has emerged as a new strategy for cancer therapy. As an alternative nucleic acid material, messenger ribonucleic acid (mRNA) is being increasingly utilized in cancer gene therapy. However, unfulfilled requirements and a lack of ideal mRNA delivery vectors persist.. We developed an advanced mRNA delivery system, DMP-039, by fusing a cell-penetrating peptide, cRGD-R9, and a cationic nano-sized DMP backbone together. The DMP gene vector backbone was synthesized by the self-assembly of DOTAP lipid and mPEG-PCL polymer. Introduction of the cRGD-R9 peptide onto the DMP backbone was performed to elevate the mRNA delivery capacity, which resulted in a peptide-functionalized hybrid delivery system.. The average size of the synthesized DMP-039 was 268.9 ± 12.4 nm (PDI = 0.382), with a potential of 17.4 ± 0.5 mV. The synthesized DMP-039 hybrid nanoparticles exhibited high mRNA delivery efficiency through multiple mechanisms during transmembrane transportation. By loading the encoding mRNA from the suicide gene Bim, a locally administered mBim/DMP-039 complex strongly inhibited growth in two colon cancer models. Moreover, intravenous administration of the mBim/DMP-039 complex efficiently suppressed C26 pulmonary metastatic tumor progression with high safety. The in vivo distribution, degradation, and excretion were also investigated in detail.. Our results suggest that the DMP-039 peptide-functionalized hybrid nanoparticle is an advanced candidate for mRNA-based suicide gene therapy.

Topics: Animals; Cell Line, Tumor; Colonic Neoplasms; Fatty Acids, Monounsaturated; Genetic Therapy; Humans; Mice; Mice, Inbred BALB C; Nanoparticles; Polyesters; Polyethylene Glycols; Quaternary Ammonium Compounds; RNA, Messenger

DESI2 is a novel pro-apoptotic gene. We previously reported that DESI2 overexpression induces S phase arrest and apoptosis by activating checkpoint kinases. This work was to test whether the combination of endostatin, an endogenous antiangiogenic inhibitor, with DESI2 could improve the therapy efficacy in vitro and in vivo. The recombinant plasmid co-expressing DESI2 and endostatin was encapsulated with DOTAP/Cholesterol cationic liposome. Mice bearing CT26 colon carcinoma and LL2 lung cancer were treated with the DNA-liposome complex. We found that, in vitro, the combination of DESI2 and endostatin more efficiently inhibited proliferation of CT26, LL2, HCT116 and A549 cancer cells via apoptosis, as assessed by MTT assay, colony-formation assays, flow cytometric analysis, hoechst staining and activation of caspase-3, respectively. In addition, DESI2 overexpression caused up-regulation of RPS7, a substrate of DESI2 deubiquitination. Furthermore, siRNA targeting RPS7 partially abrogated, whereas RPS7 overexpression enhanced DESI2-induced inhibition of cell proliferation. Importantly, the combination also caused DNA lesions accumulation, which further promotes apoptosis. Mechanistic rationale suggested that endostatin first inhibits DNA-PKcs kinase, and partly abrogated DESI2-induced phosphorylation of DNA-PKcs, leading to increase of DNA damage, then contributes to DESI2-induced apoptosis. In vivo, the combined gene therapy more significantly inhibited tumor growth and efficiently prolonged the survival of tumor bearing mice than mono therapy. The improved antitumor effect was associated with inhibition of cell proliferation via apoptosis, as analyzed by TUNEL assay and PCNA immunostaining. The combination also inhibited angiogenesis, as assessed by alginate-encapsulated tumor cell assay and CD31 staining. Our data suggest that the combined gene therapy of DESI2 and endostatin can significantly enhance the antitumor activity as a DNA lesions accumulator, apoptosis inducer and angiogenesis inhibitor. The present study may provide a novel method for the treatment of cancer.

Topics: A549 Cells; Angiogenesis Inhibitors; Animals; Apoptosis; Carbon-Nitrogen Lyases; Caspase 3; Cell Proliferation; Cholesterol; Colonic Neoplasms; DNA Fragmentation; Endostatins; Fatty Acids, Monounsaturated; Female; Gene Expression Regulation, Neoplastic; Genetic Therapy; HCT116 Cells; Humans; Liposomes; Lung Neoplasms; Mice; Mice, Inbred C57BL; Plasmids; Quaternary Ammonium Compounds; Ribosomal Proteins; RNA, Small Interfering; Signal Transduction; Survival Analysis; Xenograft Model Antitumor Assays

The present study aimed to establish an efficient targeted nonviral strategy for IL-12 gene transfer in colon carcinoma in vivo employing transferrin (Tf)-lipoplexes. Complexes for in vitro experiments were prepared at a 5/1(+/ - ) (lipid/DNA) charge ratio, with the ligand Tf (32 (microg/(microg DNA). Complexes for in vivo experiments contained 144 mM of total lipid (DOTAP/Chol), 60 (microg of pCMVLuc or pCMVIL-12 and 32 (microg of Tf-lipoplexes per microgram of plasmid. For intratumoral studies, CT26 (5 x 105 cells) in 50 microl of PBS were inoculated subcutaneously into the back of the mouse. Treatments began when tumor sizes reached 5-6 mm in diameter. Complexes were injected by a single intratumoral injection in a volume of 50 microl. Our in vitro results indicate that Tf-lipoplexes always mediate higher gene expression in colon (CT26) tumor cells, compared to plain-lipoplexes (without ligand) or naked plasmid. At the same time, CT26 tumor-bearing animals treated with Tf-lipoplexes containing the therapeutic gene IL-12, showed tumor growth inhibition, leading to a complete tumor regression in 75% of the treated mice (p < 0.001), without signs of recurrence. High levels of IL-12 and IFN-gamma were detected in the sera of treated mice. Mice survival also improved considerably by treatment with this system, with a survival rate of 88%, at 23 days post-administration. In summary, in this study we have developed an efficient, targeted cationic lipid-based system for the treatment of colon tumors. The vector has the advantages of ease of preparation and economy, in comparison with commercial transfection reagents, as well as, the possibility of a large scale production.

Topics: Animals; Cations; Cells, Cultured; Cholesterol; Colonic Neoplasms; Disease Models, Animal; Fatty Acids, Monounsaturated; Female; Gene Expression Regulation; Gene Transfer Techniques; Genetic Therapy; Interferon-gamma; Interleukin-12; Mice; Mice, Inbred BALB C; Plasmids; Quaternary Ammonium Compounds; Survival Rate; Transferrin

The purpose of this study was to investigate whether all-trans retinoic acid (ATRA), an active metabolite of retinal, incorporated in cationic liposomes composed of 1,2 dioleoyl-3-trimethylammonium propane (DOTAP)/cholesterol could inhibit established metastatic lung tumors by delivery to the pulmonary tumor site after intravenous injection. After intravenous injection in mice, the highest lung accumulation of [(3)H]ATRA was observed by the DOTAP/cholesterol liposomes formulation, while other formulations including [(3)H]ATRA dissolved in serum or [(3)H]ATRA incorporated in distearoyl-l-phosphatidylcholine (DSPC)/cholesterol liposomes produced little accumulation in the lung. In mice used as a model of lung cancer metastasis, ATRA incorporated in DOTAP/cholesterol liposomes, injected intravenously, reduced the number of tumor nodules compared with free ATRA or ATRA incorporated in DSPC/cholesterol liposomes. These results suggest that ATRA incorporated in cationic liposomes would be an effective strategy for differentiation therapy of lung cancer metastasis.

Topics: Animals; Antineoplastic Agents; Cations; Cell Line, Tumor; Cell Transplantation; Chemical and Drug Induced Liver Injury; Chemical Phenomena; Chemistry, Physical; Colonic Neoplasms; Drug Carriers; Fatty Acids, Monounsaturated; Injections, Intravenous; Liposomes; Lung; Lung Neoplasms; Male; Mice; Neoplasm Transplantation; Quaternary Ammonium Compounds; Rats; Rats, Inbred F344; Solubility; Tissue Distribution; Tretinoin

The power of antisense phosphodiester oligonucleotides (aODN) as regulatory molecules of gene expression is strongly limited by their low cellular uptake and very rapid nuclease-mediated degradation. This study deals with the effect of artificial cationic lipids on ODN cellular uptake and degradation in cell cultures and in human serum. At the ODN levels normally used in antisense-mediated gene regulation experiments, a cationic lipid, DOTAP, enhances the rate of ODN uptake more than 25 fold, but at lower ODN levels the effect of DOTAP is absent. These findings are consistent with a mechanism of ODN internalization by receptor-mediated saturable endocytosis that is bypassed by DOTAP. ODN degradation by nucleases is markedly prevented by DOTAP both in cultured cells and in human serum. Other cationic lipids, namely DOTMA and DOGS, exhibit very similar behaviour. The relatively slight cellular toxicity revealed by cationic lipids contribute to render these molecules very suitable for aODN vehiculation.

Topics: 3T3 Cells; Adenocarcinoma; Animals; Base Sequence; Biological Transport; Cell Line; Colonic Neoplasms; Drug Resistance; Fatty Acids, Monounsaturated; Glycine; Humans; Kinetics; Leukemia; Mice; Molecular Sequence Data; Oligonucleotides, Antisense; Quaternary Ammonium Compounds; Spermine; T-Lymphocytes; Time Factors; Tumor Cells, Cultured