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1.
Biomedicines ; 10(5)2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35625886

RESUMEN

Acquired chemoresistance of tumor cells is an unwanted consequence of cancer treatment. Overcoming chemoresistance is particularly important for efficiently improving cancer therapies. Here, using multiple lines of evidence, we report the suppressive role of SERTAD1 in apoptosis/anoikis. Among various breast cancer cell lines, higher SERTAD1 expression was found in MCF7 and MDA-MB-231 in suspension than in adherent cell culture. We revealed an unexpected phenomenon that different types of cell deaths were induced in response to different doses of doxorubicin (Dox) in breast cancer cells, presumably via lysosomal membrane permeabilization. A low dose of Dox highly activated autophagy, while a high dose of the chemotherapy induced apoptosis. Inhibition of SERTAD1 promoted the sensitivity of breast cancer cells to Dox and paclitaxel, leading to a significant reduction in tumor volumes of xenograft mice. Simultaneously targeting cancer cells with Dox and autophagy inhibition successfully induced higher apoptosis/anoikis. The novel role of SERTAD1 in maintaining cellular homeostasis has also been suggested in which lysosomal contents, including LAMP1, LAMP2, CTSB, and CTSD, were reduced in SERTAD1-deficient cells.

2.
Mol Ther Oncolytics ; 19: 105-126, 2020 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-33102693

RESUMEN

TRIP-Brs, a group of transcription factors (TFs) that modulate several mechanisms in higher organisms. However, the novel paradigm to target TRIP-Brs in specific cancer remains to be deciphered. In particular, comprehensive analysis of TRIP-Brs in clinicopathological and patients' prognosis, especially in breast cancer (BRCA), is being greatly ignored. Therefore, we explored the key roles of TRIP-Br expression, modulatory effects, mutations, immune infiltration, and prognosis in BRCA using multidimensional approaches. We found elevated levels of TRIP-Brs in numerous cancer tissues than normal. Higher expression of TRIP-Br-2/4/5 was shown to be positively associated with lower survival, tumor grade, and malignancy of patients with BRCA. Additionally, higher TRIP-Br-3/4 were also significantly linked with worse/short survival of BRCA patients. TRIP-Br-1/4/5 were significantly overexpressed and enhanced tumorigenesis in large-scale BRCA datasets. The mRNA levels of TRIP-Brs have been also correlated with tumor immune infiltrate in BRCA patients. In addition, TRIP-Brs synergistically play a pivotal role in central carbon metabolism, cancer-associated pathways, cell cycle, and thyroid hormone signaling, which evoke that TRIP-Brs may be a potential target for the therapy of BRCA. Thus, this investigation may lay a foundation for further research on TRIP-Br-mediated management of BRCA.

3.
Front Microbiol ; 11: 316, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32210931

RESUMEN

Oligoalginate lyases catalyze the degradation of alginate polymers and oligomers into monomers, a prerequisite for biotechnological utilizing alginate. In this study, we report the cloning, expression and biochemical characterization of a new polysaccharide lyase (PL) family 17 oligoalginate lyase, OalV17, from the marine bacterium Vibrio sp. SY01. The recombinant OalV17 showed metal ion independent and detergent resistant properties. Furthermore, OalV17 is an exo-type enzyme that yields alginate monomers as the main product and recognizes alginate disaccharides as the minimal substrate. Site-directed mutagenesis followed by kinetic analysis indicates that the residue Arg231 plays a key role in substrate specificity. Furthermore, a rapid and efficient alginate monomer-producing method was developed directly from Laminaria japonica. These results suggest that OalV17 is a potential candidate for saccharification of alginate.

4.
Mol Cells ; 43(3): 236-250, 2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32050753

RESUMEN

Currently, many available anti-cancer therapies are targeting apoptosis. However, many cancer cells have acquired resistance to apoptosis. To overcome this problem, simultaneous induction of other types of programmed cell death in addition to apoptosis of cancer cells might be an attractive strategy. For this purpose, we initially investigated the inhibitory role of TRIP-Br1/XIAP in necroptosis, a regulated form of necrosis, under nutrient/serum starvation. Our data showed that necroptosis was significantly induced in all tested 9 different types of cancer cell lines in response to prolonged serum starvation. Among them, necroptosis was induced at a relatively lower level in MCF-7 breast cancer line that was highly resistant to apoptosis than that in other cancer cell lines. Interestingly, TRIP-Br1 oncogenic protein level was found to be very high in this cell line. Upregulated TRIP-Br1 suppressed necroptosis by repressing reactive oxygen species generation. Such suppression of necroptosis was greatly enhanced by XIAP, a potent inhibitor of apoptosis. Our data also showed that TRIP-Br1 increased XIAP phosphorylation at serine87, an active form of XIAP. Our mitochondrial fractionation data revealed that TRIPBr1 protein level was greatly increased in the mitochondria upon serum starvation. It suppressed the export of CypD, a vital regulator in mitochondria-mediated necroptosis, from mitochondria to cytosol. TRIP-Br1 also suppressed shikoninmediated necroptosis, but not TNF-α-mediated necroptosis, implying possible presence of another signaling pathway in necroptosis. Taken together, our results suggest that TRIPBr1/XIAP can function as onco-proteins by suppressing necroptosis of cancer cells under nutrient/serum starvation.


Asunto(s)
Neoplasias/metabolismo , Nutrientes/deficiencia , Factores de Transcripción/metabolismo , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Células A549 , Apoptosis/fisiología , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Células HCT116 , Humanos , Células MCF-7 , Necroptosis/fisiología , Neoplasias/patología , Factores de Transcripción/deficiencia , Factores de Transcripción/genética
5.
Int J Mol Sci ; 20(18)2019 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-31540110

RESUMEN

Bacterial biofilm causes severe antibiotic resistance. An extracellular polymeric substance (EPS) is the main component in the bacterial biofilm. Alginate is a key EPS component in the biofilm of Pseudomonas aeruginosa and responsible for surface adhesion and stabilization of biofilm. Alginate lyase has emerged as an efficient therapeutic strategy targeting to degrade the alginate in the biofilm of P. aeruginosa. However, the application of this enzyme is limited by its poor stability. In this study, chitosan nanoparticles (CS-NPs) were synthesized using low molecular weight chitosan and alginate lyase Aly08 was immobilized on low molecular weight chitosan nanoparticles (AL-LMW-CS-NPs). As a result, the immobilization significantly enhanced the thermal stability and reusability of Aly08. In addition, compared with free Aly08, the immobilized AL-LMW-CS-NPs exhibited higher efficiency in inhibiting biofilm formation and interrupting the established mature biofilm of P. aeruginosa, which could reduce its biomass and thickness confirmed by confocal microscopy. Moreover, the biofilm disruption greatly increased the antibiotic sensitivity of P. aeruginosa. This research will contribute to the further development of alginate lyase as an anti-biofilm agent.


Asunto(s)
Alginatos/química , Biopelículas/efectos de los fármacos , Quitosano/química , Nanopartículas/química , Polisacárido Liasas/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Antibacterianos/farmacología , Farmacorresistencia Microbiana , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Enzimas Inmovilizadas/farmacología , Matriz Extracelular de Sustancias Poliméricas/química , Peso Molecular , Nanopartículas/ultraestructura , Polisacárido Liasas/química , Polisacárido Liasas/metabolismo , Temperatura
6.
Cancers (Basel) ; 11(9)2019 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-31450709

RESUMEN

Lung cancer is a type of deadly cancer and a leading cause of cancer associated death worldwide. BCL-2 protein is considered as an imperative target for the treatment of cancer due to their significant involvement in cell survival and death. A carbazole-piperazine hybrid molecule ECPU-0001 was designed and synthesized as a potent BCL-2 targeting agent with effective anticancer cancer activity. Interaction of ECPU-001 has been assessed by docking, molecular dynamics (MD) simulation, and thermal shift assay. Further, in vitro and in vivo anticancer activity was executed by cytotoxicity assay, FACS, colony formation and migration assay, western blotting, immunocyto/histochemistry and xenograft nude mice model. Molecular docking and MD simulation study confirmed that ECPU-0001 nicely interacts with the active site of BCL-2 by displaying a Ki value of 5.72 µM and binding energy (ΔG) of -8.35 kcal/mol. Thermal shift assay also validated strong interaction of this compound with BCL-2. ECPU-0001 effectively exerted a cytotoxic effect against lung adenocarnoma cells A459 with an IC50 value of 1.779 µM. Molecular mechanism of action have also been investigated and found that ECPU-0001 induced apoptosis in A459 cell by targeting BCL-2 to induce intrinsic pathway of apoptosis. Administration of ECPU-0001 significantly inhibited progression of tumor in a xenograft model without exerting severe toxicity and remarkably reduced tumor volume as well as tumor burden in treated animals. Our investigation bestowed ECPU-0001 as an effective tumoricidal agent which exhibited impressive anticancer activity in vitro as well as in vivo by targeting BCL-2 associated intrinsic pathway of apoptosis. Thus, ECPU-0001 may provide a valuable input for therapy of lung adenosarcoma in future, however, further extensive investigation of this compound will be needed.

7.
Cancers (Basel) ; 11(3)2019 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-30857225

RESUMEN

SERTAD/TRIP-Br genes are considered as a key nuclear transcriptional player in diverse mechanisms of cell including carcinogenesis. The Oncomine™-Online Platform was used for differential expression and biological insights. Kaplan-Meier survival estimated by KM-plotter/cBioPortal/PrognoScan with 95% CI. SERTAD1 was found significantly elevated levels in most of tumor samples. Kaplan-Meier Plotter results distinctly showed the SERTAD1 over-expression significantly reduced median overall-survival (OS) of patients in liver (n = 364/Logrank-test p = 0.0015), ovarian (n = 655/Logrank-test p = 0.00011) and gastric (n = 631/Logrank-test p = 0.1866). Increased level of SERTAD1 has a significantly higher survival rate in the initial time period, but after 100 months slightly reduced OS (n = 26/Logrank-test p = 0.34) and RFS in HER2 positive breast cancer patients. In meta-analysis, cancer patients with higher SERTAD1 mRNA fold resulted worse overall survival than those with lower SERTAD1 levels. Heterogeneity was observed in the fixed effect model analysis DFS [Tau² = 0.0.073, Q (df = 4) = 15.536 (p = 0.004), I² = 74.253], DSS [Tau² = 1.015, Q (df = 2) = 33.214, (p = 0.000), I² = 93.973], RFS [Tau² = 0.492, Q (df = 7) = 71.133 (p = 0.000), I² = 90.159] (Figure 5). OS [Tau² = 0.480, Q (df = 17) = 222.344 (p = 0.000), I² = 92.354]. Lastly, SERTAD1 involved in several signaling cascades through interaction and correlation with many candidate factors as well as miRNAs. This meta-analysis demonstrates a robust evidence of an association between higher or lower SERTAD1, alteration and without alteration of SERTAD1 in cancers in terms of survival and cancer invasiveness.

8.
Int J Oncol ; 54(2): 702-712, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30431068

RESUMEN

Simultaneous induction of other types of programmed cell death, alongside apoptosis, in cancer cells may be considered an attractive strategy for the development of more effective anticancer therapies. The present study aimed to investigate the role of AMP­activated protein kinase (AMPK) in nutrient/serum starvation­induced necroptosis, which is a programmed form of necrosis, in the presence or absence of p53. The present study detected higher cell proliferation and lower cell death rates in the HCT116 human colon cancer cell line containing a p53 null mutation (HCT116 p53­/­) compared with in HCT116 cells harboring wild­type p53 (HCT116 p53+/+), as determined using a cell viability assay. Notably, western blot analysis revealed a relatively lower level of necroptosis in HCT116 p53­/­ cells compared with in HCT116 p53+/+ cells. Investigating the mechanism, it was revealed that necroptosis may be induced in HCT116 p53+/+ cells by significantly increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential (MMP), whereas little alterations were detected in HCT116 p53­/­ cells. Unexpectedly, a much lower level of ATP was detected in HCT116 p53­/­ cells compared with in HCT116 p53+/+ cells. Accordingly, AMPK phosphorylation on the Thr172 residue was markedly increased in HCT116 p53­/­ cells. Furthermore, western blot analysis and ROS measurements indicated that AMPK inhibition, using dorsomorphin dihydrochloride, accelerated necroptosis by increasing ROS generation in HCT116 p53­/­ cells. However, AMPK activation by AICAR did not suppress necroptosis in HCT116 p53+/+ cells. In conclusion, these data strongly suggested that AMPK activation may be enhanced in HCT116 p53­/­ cells under serum­depleted conditions via a drop in cellular ATP levels. In addition, activated AMPK may be at least partially responsible for the inhibition of necroptosis in HCT116 p53­/­ cells, but not in HCT116 p53+/+cells.


Asunto(s)
Proteínas Quinasas Activadas por AMP/genética , Neoplasias del Colon/genética , Necrosis/genética , Proteína p53 Supresora de Tumor/genética , Apoptosis/genética , Proliferación Celular/genética , Supervivencia Celular/genética , Neoplasias del Colon/patología , Células HCT116 , Humanos , Mutación con Pérdida de Función/genética , Potencial de la Membrana Mitocondrial/genética , Nutrientes/metabolismo , Especies Reactivas de Oxígeno/metabolismo
9.
Oncotarget ; 9(24): 16744-16757, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29682182

RESUMEN

Angelica amurensis has traditionally been used to treat various medical problems. In this report, we introduce cis-khellactone as a new anti-cancer agent, which was isolated from the chloroform soluble fraction of the rhizomes of Angelica amurensis. Its anti-cancerous effect was at first tested in MCF7 and MDA-MB-231 breast cell lines, in which MCF7 is well known to be resistant to many anti-cancer drugs; MCF10A normal breast cell line was used as a control. In vitro experiments showed that cis-khellactone suppressed cell growth and proliferation at a relatively low concentrations (<5 µg/ml) and decreased cell viability at high concentrations (>10 µg/ml) in both cancer cell lines in a time- and concentration-dependent manner. This anti-cancerous effect was also checked in additional 16 different types of normal and cancer cell lines. Cis-khellactone treatment significantly suppressed cell proliferation and enhanced cell death in all tested cancer cell lines. Furthermore, Western blot analysis showed that cis-khellactone induced three types of programmed cell death (PCD): apoptosis, autophagy-mediated cell death, and necrosis/necroptosis. Cis-khellactone concentration-dependently decreased cell viability by increasing the level of reactive oxygen species (ROS) and decreasing mitochondrial membrane potential (MMP), which are related to all three types of PCD. Mitochondrial fractionation data revealed that cis-khellactone induced the translocation of BAX and BAK into mitochondria as well as the overexpression of VDAC1, which probably accelerates MMP disruption and finally cell death. Importantly, our extended in vivo studies with xenograft model further confirmed these findings of anti-cancerous effects and showed no harmful effects in normal tissues, suggesting that there would be no side effects in humans.

10.
ACS Biomater Sci Eng ; 4(4): 1445-1462, 2018 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33418674

RESUMEN

Currently, there is great interest in the development of ways to achieve the benefits of radiation treatments with reduced negative effects. The present study demonstrates the utilization of radio-luminescent particles (RLPs) as a means to achieve radio-sensitization and enhancement and their ability to affect head- and neck-cancer-cell cultures (in vitro) and xenografts (in vivo). Our approach utilizes a naturally abundant radio-luminescent mineral, calcium tungstate (CaWO4), in its micro or nanoparticulate form for generating secondary UV-A light by γ ray or X-ray photons. In vitro tests demonstrate that unoptimized RLP materials (uncoated CaWO4 (CWO) microparticles (MPs) and PEG-PLA-coated CWO nanoparticles (NPs)) induce a significant enhancement of the tumor-suppressive effect of X-rays and γ rays in both radio-sensitive- and radio-resistant-cancer models; uncoated CWO MPs and PEG-PLA-coated CWO NPs demonstrate comparable radio-sensitization efficacies in vitro. Mechanistic studies reveal that concomitant CaWO4 causes increased mitotic death in radio-resistant cells treated with radiation, whereas CaWO4 sensitizes radio-sensitive cells to X-ray-induced apoptosis and necrosis. The radio-sensitization efficacy of intratumorally injected CaWO4 particles (uncoated CWO MPs and PEG-PLA-coated CWO NPs) is also evaluated in vivo in mouse head- and neck-cancer xenografts. Uncoated CWO MPs suppress tumor growth more effectively than PEG-PLA-coated CWO NPs. On the basis of theoretical considerations, an argument is proposed that uncoated CWO MPs release subtoxic levels of tungstate ions, which cause increased photoelectric-electron-emission effects. The effect of folic acid functionalization on the in vitro radio-sensitization behavior produced by PEG-PLA-coated CWO NPs is studied. Surface folic acid results in a significant improvement in the radio-sensitization efficiency of CaWO4.

11.
Int J Cancer ; 141(9): 1912-1920, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-28635011

RESUMEN

Chemotherapy have commonly been used in maximum tolerated dose to completely eradicate the cancer. However, such treatments often failed due to the complex and dynamic nature of cancer. Therefore, it has been suggested that cancer should be treated as a chronic disease, controlling its growth by providing continuous therapeutic pressure for long-term. Such an approach, however, requires a therapy that is non-toxic and orally available with sufficient potency. Herein, we propose a radiotherapy-assisted orally available metronomic apoptosis-targeted chemotherapy, which delivers doxorubicin continuously to the irradiated tumor with high selectivity while causing minimal toxicities to the normal tissues. DEVD-S-DOX/DCK complex is the anticancer prodrug for our strategy that could selectively release doxorubicin in the irradiated tumor tissue with sufficient oral bioavailability. The prodrug was completely inactive by itself, but displayed potent anticancer activity when coupled with radiotherapy. Consequently, the daily oral administration of DEVD-S-DOX/DCK in combination with the low-dose radiotherapy effectively suppressed the growth of tumor in vivo with no significant systemic toxicities despite that the accumulated dose of doxorubicin exceeded 150 mg/kg. Therefore, the our novel therapy using DEVD-S-DOX/DCK complex is considered as an outstanding treatment option for treating cancer for long-term attributed to its oral availability and low-toxicity profile as well as the potent anticancer effect.


Asunto(s)
Doxorrubicina/administración & dosificación , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Profármacos/administración & dosificación , Administración Oral , Animales , Apoptosis/efectos de los fármacos , Células CACO-2 , Terapia Combinada , Doxorrubicina/química , Sistemas de Liberación de Medicamentos , Humanos , Dosis Máxima Tolerada , Ratones , Neoplasias/patología , Profármacos/química , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Biochem Biophys Res Commun ; 489(1): 35-41, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28533089

RESUMEN

A variety of VEGF inhibitors have been reported to treat cancers by suppressing tumor angiogenesis. Bevacizumab, a monoclonal VEGF antibody, was the first FDA approved anti-angiogenic agent for cancer treatments. However, bevacizumab shows modest therapeutic efficiency and often cause resistant problem in significant populations of cancer patients. To solve these problem, we investigated the therapeutic efficacy of siRNA drugs targeting VEGF and combination of the RNAi drug with bevacizumab for cancer treatments. For efficient VEGF siRNA delivery, chemically polymerized siRNAs were complexed with thiolated-glycol chitosan (psi(VEGF)/tGC). The poly-VEGF siRNA and thiolated-glycol chitosan formed stable nanoparticles via electrostatic interaction and chemical crosslinking, and showed high accumulation in tumor tissues resulting in efficient gene silencing. Both VEGF siRNA nanoparticles and bevacizumab had efficient therapeutic effects in tumor xenograft mouse models. Interestingly, most pronounced therapeutic efficacy was observed when the two distinct VEGF inhibitors were treated in combination revealing synergistic effects. The results showed that the psi(VEGF)/tGC nanoparticle mediated knockdown of VEGF exerts anti-tumor effects and the combination treatments with bevacizumab can extend the treatments options to conventional bevacizumab treatments for cancer therapy.


Asunto(s)
Antineoplásicos/farmacología , Bevacizumab/farmacología , Nanopartículas/química , ARN Interferente Pequeño/farmacología , Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Bevacizumab/administración & dosificación , Bevacizumab/química , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Silenciador del Gen/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Polimerizacion/efectos de los fármacos , ARN Interferente Pequeño/química , Células Tumorales Cultivadas , Factores de Crecimiento Endotelial Vascular/genética , Factores de Crecimiento Endotelial Vascular/metabolismo
13.
J Control Release ; 228: 141-149, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-26970205

RESUMEN

A combination therapy consisting of radiotherapy and chemotherapy is performed using the core/shell nanoparticles (NPs) containing gold NPs and doxorubicin (DOX). Gold NPs in the core/shell NPs were utilized as a radiosensitizer. To examine the morphology and size distribution of the core/shell NPs, transmittance electron microscopy and dynamic light scattering were used. The in vitro release behavior, cellular uptake and toxicity were also observed to verify the functionality of the core/shell NPs as a nanocarrier. To demonstrate the advantage of the core/shell NPs over traditional gold NPs reported in the combination therapy, we evaluated the accumulation behavior of the core/shell NPs at the tumor site using the biodistribution. Antitumor efficacy was observed with and without radiation to evaluate the role of gold NPs as a radiosensitizer.


Asunto(s)
Antibióticos Antineoplásicos/uso terapéutico , Doxorrubicina/uso terapéutico , Oro/uso terapéutico , Nanopartículas del Metal/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacocinética , Línea Celular Tumoral , Quimioradioterapia , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Sistemas de Liberación de Medicamentos , Oro/administración & dosificación , Oro/farmacocinética , Humanos , Masculino , Nanopartículas del Metal/administración & dosificación , Ratones , Fármacos Sensibilizantes a Radiaciones/administración & dosificación , Fármacos Sensibilizantes a Radiaciones/farmacocinética , Distribución Tisular
14.
J Med Chem ; 58(16): 6435-47, 2015 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-26263187

RESUMEN

The current study demonstrates the process of selecting an optimal structure for a caspase-3-cleavable doxorubicin prodrug that could be synthesized by simple chemistry in high yields. The prodrug was intended to activate in the presence of caspase-3, whose expression can be exogenously regulated by inducing apoptosis with radiation therapy at a specific site of interest. For this purpose, doxorubicin was conjugated with a DEVD peptide via a heterobifunctional linker. Since the active form of the prodrug comprises the linker besides doxorubicin, we tested several different linkers and selected EMCS based on the examination of its in vitro biological activities. Consequently, DEVD-cysteamide-EMCS-doxorubicin was synthesized as the final compound. According to the various in vitro and in vivo studies, the synthesized prodrug was highly selective for tumors when coupled with radiation therapy, with the added benefit of ease of production.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Caspasa 3/efectos de los fármacos , Caspasa 3/efectos de la radiación , Doxorrubicina/farmacología , Oligopéptidos/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Línea Celular Tumoral , Doxorrubicina/química , Doxorrubicina/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Oligopéptidos/química , Oligopéptidos/metabolismo , Profármacos/síntesis química , Profármacos/farmacología
15.
J Natl Cancer Inst ; 107(2)2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25505252

RESUMEN

BACKGROUND: Tumor heterogeneity and evolutionary complexity may underlie treatment failure in spite of the development of many targeted agents. We suggest a novel strategy termed induced phenotype targeted therapy (IPTT) to simplify complicated targets because of tumor heterogeneity and overcome tumor evolutionary complexity. METHODS: We designed a caspase-3 specific activatable prodrug, DEVD-S-DOX, containing doxorubicin linked to a peptide moiety (DEVD) cleavable by caspase-3 upon apoptosis. To induce apoptosis locally in the tumor, we used a gamma knife, which can irradiate a very small, defined target area. The in vivo antitumor activity of the caspase-3-specific activatable prodrug combined with radiation was investigated in C3H/HeN tumor-bearing mice (n = 5 per group) and analyzed with the Student's t test or Mann-Whitney U test. All statistical tests were two-sided. We confirmed the basic principle using a caspase-sensitive nanoprobe (Apo-NP). RESULTS: A single exposure of radiation was able to induce apoptosis in a small, defined region of the tumor, resulting in expression of caspase-3. Caspase-3 cleaved DEVD and activated the prodrug. The released free DOX further activated DEVD-S-DOX by exerting cytotoxic effects on neighboring tumor or supporting cells, which repetitively induced the expression of caspase-3 and the activation of DEVD-S-DOX. This sequential and repetitive process propagated the induction of apoptosis. This novel therapeutic strategy showed not only high efficacy in inhibiting tumor growth (14-day tumor volume [mm(3)] vs radiation alone: 848.21 ± 143.24 vs 2511.50 ± 441.89, P < .01) but also low toxicity to normal cells and tissues. CONCLUSION: Such a phenotype induction strategy represents a conceptually novel approach to overcome tumor heterogeneity and complexity as well as to substantially improve current conventional chemoradiotherapy with fewer sequelae and side effects.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Caspasa 3/metabolismo , Doxorrubicina/farmacología , Terapia Molecular Dirigida/métodos , Péptido Hidrolasas/farmacología , Profármacos , Radiocirugia , Animales , Western Blotting , Caspasa 3/efectos de los fármacos , Doxorrubicina/administración & dosificación , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de la radiación , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Inmunohistoquímica , Ratones , Ratones Endogámicos C3H , Microscopía Fluorescente , Péptido Hidrolasas/administración & dosificación , Fenotipo , Profármacos/administración & dosificación , Profármacos/farmacología , Radioterapia Adyuvante
16.
Biomaterials ; 33(35): 9070-9, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23010574

RESUMEN

Heparin, a potent anticoagulant used for the prevention of venous thromboembolism, has been recognized as a tumor angiogenesis inhibitor. Its limitation in clinical application for cancer therapy, however, arises from its strong anticoagulant activity, which causes associated adverse effects. In this study, we show the structural correlation of LHT7, a previously developed heparin-based angiogenesis inhibitor, with its influence on VEGF blockade and its decreased anticoagulant activity. LHT7 was characterized as having average seven molecules of sodium taurocholates conjugated to one molecule of low-molecular-weight heparin (LMWH). This study showed that the conjugation of sodium taurocholates selectively blocked interaction with antithrombin III (ATIII) while enhancing the binding with VEGF. This resulted in LHT7 to have negligible anticoagulant activity but potent anti-angiogenic activity. Following up on this finding, we showed that the bidirectional effect of sodium taurocholate conjugation was due to its unique structure, that is, the sterane core hindering the ATIII-binding pentasaccharide unit of LMWH with its bulky and rigid structural characteristics while the terminal sulfate group interacts with VEGF to produce stronger binding. In addition, we showed that LHT7 was localized in the tumor, especially on the endothelial cells. One explanation for this might be that LHT7 was delivered to the tumor via platelets.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Anticoagulantes/farmacología , Antitrombina III/antagonistas & inhibidores , Heparina de Bajo-Peso-Molecular/química , Heparina de Bajo-Peso-Molecular/farmacología , Aniones/química , Antitrombina III/química , Línea Celular Tumoral , Células HT29 , Humanos , Neovascularización Patológica , Oligosacáridos/antagonistas & inhibidores , Oligosacáridos/química , Ácido Taurocólico/química , Factor A de Crecimiento Endotelial Vascular/química
17.
Biomaterials ; 33(26): 6186-93, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22687759

RESUMEN

Colon cancer is the second leading cause of cancer-related death in the United States. The considerable mortality from colon cancer is due to metastasis to other organs, mainly the liver. In the management of colon cancer, early detection and targeted therapy are crucial. In this study, we aimed to establish a versatile theranostic system for early tumor detection and targeted tumor therapy by using poly(ethylene glycol)-conjugated hyaluronic acid nanoparticles (P-HA-NPs) which can selectively accumulate in tumor tissue. For the diagnostic application, a near-infrared fluorescence (NIRF) imaging dye (Cy 5.5) was chemically conjugated onto the HA backbone of P-HA-NPs. After intravenous injection of Cy5.5-P-HA-NPs into the tumor-bearing mice, small-sized colon tumors as well as liver-implanted colon tumors were effectively visualized using the NIRF imaging technique. For targeted therapy, we physically encapsulated the anticancer drug, irinotecan (IRT), into the hydrophobic cores of P-HA-NPs. Owing to their notable tumor targeting capability, IRT-P-HA-NPs exhibited an excellent antitumor activity while showing a reduction in undesirable systemic toxicity. Importantly, we demonstrated the theranostic application using Cy5.5-P-HA-NPs and IRT-P-HA-NPs in orthotopic colon cancer models. Following the systemic administration of Cy5.5-P-HA-NPs, neoplasia was clearly visualized, and the tumor growth was effectively suppressed by intravenous injection of IRT-P-HA-NPs. It should be emphasized that the therapeutic responses could be simultaneously monitored by Cy5.5-P-HA-NPs. Our results suggest that P-HA-NPs can be used as a versatile theranostic system for the early detection, targeted therapy, and therapeutic monitoring of colon cancer.


Asunto(s)
Neoplasias del Colon/diagnóstico , Neoplasias del Colon/tratamiento farmacológico , Ácido Hialurónico/química , Nanopartículas/uso terapéutico , Polietilenglicoles/química , Animales , Células HT29 , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nanopartículas/química , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Biomaterials ; 33(7): 2251-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22189146

RESUMEN

The long-term theranostic hydrogel system for solid tumors was prepared via simple physical mixing, which consisted of three major parts: the thermosensitive/biodegradable poly(organophosphazene) hydrogel, PEGylated cobalt ferrite nanoparticles, and paclitaxel (PTX). The PEGylated cobalt ferrite nanoparticles showed extremely low cytotoxicity due to the surface modification using PEG chains. The long-term theranostic hydrogel system showed adequate properties to be used for long-term MR theragnosis. In particular, the theranostic hydrogel gradually degraded over 28 days, and the PTX was sustainedly released out from the theranostic hydrogel over the same period in vitro. Furthermore, the in vivo efficacy of long-term MR theragnosis using the theranostic hydrogel system was estimated successfully over 3 weeks by using high field (4.7 T) animal MRI and solid tumor-bearing mice. Based on our results, we expect that this system can supply multiple data regarding a) the progress of therapy and b) the treatment processes via one- or two-time i.t. administration for cases in which surgical approaches are difficult to apply. Meanwhile, cancer patients can be free from the pain of multiple surgical treatments and have the advantage of therapy through a simple i.t. administration.


Asunto(s)
Antineoplásicos , Sistemas de Liberación de Medicamentos , Hidrogeles/química , Hidrogeles/metabolismo , Neoplasias Experimentales/tratamiento farmacológico , Paclitaxel , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapéutico , Materiales Biocompatibles/química , Materiales Biocompatibles/metabolismo , Línea Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Humanos , Ensayo de Materiales , Nanopartículas del Metal/química , Ratones , Ratones Desnudos , Paclitaxel/química , Paclitaxel/metabolismo , Paclitaxel/uso terapéutico
19.
Opt Express ; 19(18): 17372-7, 2011 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-21935101

RESUMEN

We design a high dynamic range electric field sensor based on domain inverted electro-optic (E-O) polymer Y-fed directional coupler for electromagnetic wave detection. This electrode-less, all optical, wideband electrical field sensor is fabricated using standard processing for E-O polymer photonic devices. Experimental results demonstrate effective detection of electric field from 16.7V/m to 750KV/m at a frequency of 1GHz, and spurious free measurement range of 70dB.

20.
Biomacromolecules ; 12(6): 2335-43, 2011 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-21506550

RESUMEN

We described the preparation of the glycol chitosan/heparin immobilized iron oxide nanoparticles (composite NPs) as a magnetic resonance imaging agent with a tumor-targeting characteristic. The iron oxide nanoseeds used clinically as a magnetic resonance imaging agent were immobilized into the glycol chitosan/heparin network to form the composite NPs. To induce the ionic interaction between the iron oxide nanoseeds and glycol chitosan, gold was deposited on the surface of iron oxide nanoseeds. After the immobilization of gold-deposited iron oxide NPs into the glycol chitosan network, the NPs were stabilized with heparin based on the ionic interaction between cationic glycol chitosan and anionic heparin. FE-SEM (field emission-scanning electron microscopy) and a particle size analyzer were used to observe the formation of the stabilized composite NPs, and a Jobin-Yvon Ultima-C inductively coupled plasma-atomic emission spectrometer (ICP-AES) was used to measure the contents (%) of formed iron oxide nanoseeds as a function of reaction temperature and formed gold deposited on the iron oxide nanoparticles. We also evaluated the time-dependent excretion profile, in vivo biodistribution, circulation time, and tumor-targeting ability of the composite NPs using a noninvasive NIR fluorescence imaging technology. To observe the MRI contrast characteristic, the composite NPs were injected into the tail veins of tumor-bearing mice to demonstrate their selective tumoral distribution. The MR images were collected with conventional T(2)-weighted spin echo acquisition parameters.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Quitosano/química , Compuestos Férricos/química , Oro/química , Heparina/química , Imagen por Resonancia Magnética/métodos , Nanopartículas/química , Animales , Aniones , Carcinoma de Células Escamosas/patología , Cationes , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Compuestos Férricos/farmacocinética , Fluorescencia , Masculino , Ratones , Microscopía Electrónica de Rastreo , Nanopartículas/ultraestructura , Tamaño de la Partícula , Polisorbatos/química , Radiografía , Espectrofotometría Infrarroja , Temperatura , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
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