Combination Of Dox Research Articles

Red Betel Leaves Methanolic Extract (Piper crocatum Ruiz & Pav.) Increases Cytotoxic Effect of Doxorubicin on WiDr Colon Cancer Cells through Apoptosis Induction

Doxorubicin is a chemotherapeutic agent that causes a lot of side effects in high doses. Thus, combination with a co-chemotherapeutic agent which can increase its toxicity on cancer cells, is needed to reduce its therapeutic dose. Red betel leaves (Piper crocatum Ruiz & Pav.) have been known to contain flavonoids and alkaloids that have anticancer activity. This study was conducted to determine the cytotoxic effect and apoptosis induction of red betel leaves methanolic extract (RBM), doxorubicin (dox) and the combination of them on WiDr cells as model of colon cancer. RBM was extracted by soxhlet method using methanol. Cytotoxicity assay was performed using MTT assay for both single and combination treatments for 24 hours to determine IC50 and CI as their parameters. Apoptosis induction was analyzed by double staining method using ethidium bromide-acridine orange staining. Treatment of RBM and dox on WiDr cells for 24 hours showed cytotoxic activity with IC50 100 μg/mL and 1.6 μM respectively. Combination of RBM and dox performed synergism effect with CI<0.9 (p<0.05). Combination of RBM (12.5 μg/mL) and dox (0.4 μM) increased the number of apoptosis cells compared to each single treatment. Based on this study, it can be concluded that red betel leaves methanolic extract is potential to be developed as a co-chemotherapeutic agent of doxorubicin on colon cancer but still need further study to disclose the underlying molecular mechanisms.Keywords : Red betel leaves (Piper crocatum Ruiz & Pav.), doxorubicin, WiDr cells, co- chemotherapeutic agent

Abstract P4-03-05: AP-1 as a potential mediator of resistance to the cyclin-dependent kinase (CDK) 4/6-inhibitor palbociclib in ER-positive endocrine-resistant breast cancer

Abstract Background: The CDK4/6-inhibitor palbociclib (Palbo) in combination with endocrine therapy (ET) substantially improves progression-free survival compared to ET alone. However, almost all initial responders eventually develop resistance and relapse. Delineating the early adaptive signaling and the mechanisms underlying resistance to CDK4/6 inhibition is therefore crucial to identify new biomarkers and therapeutic targets to enhance the efficacy of Palbo and improve patient outcome. Materials and Methods: MCF7 parental (P) cells and derivative lines made resistant (R) to tamoxifen (TamR), estrogen deprivation (EDR), or fulvestrant (FulR) were used. The MCF7P line and its endocrine-R (EndoR) derivatives were exposed to increasing concentrations of Palbo to generate acquired Palbo-R (PDR) models. The proteomic/signaling profiles of P and EndoR cells upon short-term Palbo treatment and as PDR develops were determined using reverse-phase protein arrays (RPPA). Transcriptional activity of the activator protein-1 (AP-1) transcription factor (TF) was measured by luciferase reporter assay. Global AP-1 blockade was achieved using a pINDUCER system to express doxycycline (Dox)-inducible dominant-negative (DN) c-Jun that lacks the transcriptional activation domain. Cell growth and colony formation were assessed using methylene blue staining and clonogenic assays, respectively. Levels of phosphorylated (p)-RB and CDK2 were assessed by Western Blot. Results: In P and all EndoR cell models, Palbo inhibited cell growth and colony formation in a dose-dependent manner, though the inhibitory effect was greater in the EndoR cells compared to P cells [IC50 value of P cells >3 times that of EndoR lines (p<0.001); clonogenic % inhibition at 100nM = 54 in P and >85 in EndoR lines (p<0.001)]. Across the P and all EndoR models, short-term Palbo treatment resulted in increased levels of several membrane and intracellular signaling molecules, TFs, and enzymes. Among these, the AP-1 TF components c-Jun and p-c-Jun showed the highest increase across all models, with the utmost change observed in the TamR model (Fold-change = 4.4, 4.0 for total and p-c-Jun, respectively). Since we also observed that acquired resistance to Palbo in the TamR model was associated with higher AP-1 transcriptional activity and increased total and p-c-Fos levels, we assessed the efficacy of combining Palbo with AP-1 blockade in the TamR model. In two independent TamR clones ectopically expressing inducible DN-c-Jun, AP-1 blockade (+Dox) in combination with Palbo was highly effective in inhibiting cell growth and reducing p-RB and CDK2 levels compared to single agent treatments. In addition, in both the TamR/DN-c-Jun-expressing clones, the combination of Palbo, AP-1 blockade, and fulvestrant resulted in cell death and a significantly greater cell growth inhibition compared to any dual or mono treatments. Conclusion: Our results suggest activation of AP-1 as a potential mechanism of resistance to Palbo in ER+ EndoR models. Transcriptomic profiling of the Palbo-sensitive and R cells, currently underway, will provide an in-depth understanding of the role of AP-1 as well as other key targets and associated molecular mechanisms in Palbo resistance. Citation Format: De Angelis C, Nardone A, Cataldo ML, Veeraraghavan J, Fu X, Giuliano M, Malorni L, Jeselsohn R, Osborne KC, Schiff R. AP-1 as a potential mediator of resistance to the cyclin-dependent kinase (CDK) 4/6-inhibitor palbociclib in ER-positive endocrine-resistant breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-03-05.

Chitosan nanoparticles triggered the induction of ROS-mediated cytoprotective autophagy in cancer cells

There is a close relationship between autophagy and apoptosis during cancer cell death. We used chitosan nanoparticles (CS NPs) to explore the effects of internalized NPs on the induction of autophagy and to confirm the role of autophagic responses elicited by nanomaterials on the tumour cell’s fate. CS NPs at nontoxic concentrations ranging from 10–100 μg/mL triggered the induction of autophagy. With the addition of CS NPs, the aggregation of endogenous LC3 was significantly enhanced and acidic autophagic bodies had been accumulated. CS NPs significantly triggered the occurrence of autophagy by increasing the ratio of LC3 II to LC3 I and CS NPs-mediated autophagy was implicated in reactive oxygen species (ROS) generation and the ROS scavenger N-acetylcysteine (NAC) attenuated CS-induced autophagy. The addition of blank NPs produced a negative effect on cytotoxicity and cellular apoptosis of free Dox, and with the pre-treatment of chloroquine (CQ) as a known autophagy inhibitor, the inhibition rates of cells treated with the combination of Dox and blank CS NPs had been significantly increased. The findings demonstrated that CS NPs have the ability to induce protective autophagy via ROS generation and they were believed to inhibit tumour cell death.

Evaluation of anticancer and antimicrobial activities of the Polygonum maritimum ethanol extract

Polygonum maritimum is a traditional herbal remedy that produces abundant flavonoid secondary metabolites. The ethanol extract of P. maritimum aerial parts (POM) was chemically characterized and tested for antimicrobial properties and cytotoxicity. Results of LC-MS/MS analysis showed high contents of gallic acid, epigallocatechin gallate and catechin, and significant amounts of quercetin-3-O-galactoside and quercetin-3-O-glucoside. Evaluation of the antifungal properties revealed that POM induced notable growth inhibition of Alternaria alternata (34.3%), Penicillium spp. (30.6%), Fusarium semitectum (20.2%) and Aspergillus spp. (19.6%). Evaluation of cytotoxicity against human hepatoma HepG2 cells included monitoring the effects of both POM alone and its combination with cytostatic doxorubicin (Dox). Cell viability, apoptosis and cell cycle distribution and the expression of antioxidant enzymes (superoxide-dismutases SOD1 and SOD2 and catalase) were determined. A dose-dependent decrease in cell viability was detected, but a remarkably stronger effect was obtained when POM and Dox were applied in combination as compared to individual treatments. IC50 values were determined to be 393 ?g/mL (POM) and 2.24 ?g/mL (Dox) in combination, but 1153 ?g/mL (POM) and 12.56 ?g/mL (Dox) in a single treatment. The value of the Loewe index, determined for IC50, was notably lower than 1 (LI=0.51), clearly indicating synergism of POM and Dox. Additionally, POM and POM +Dox induced early/late apoptosis and G2/M cell cycle arrest. Furthermore, POM increased, while Dox decreased the expression levels of SODs and catalase. The obtained results encourage further examination of the potential use of POM in modern phytotherapy.

The effects of combination of Eurycoma longifolia Jack ethanolic extract and doxorubicine on hematological profile in rats given by 7,12-dimethylbenz(a)anthracene

Doxorubicin (Dox) is known as anticancer drug commonly used for cancer treatment. Eurycoma longifolia Jack or Pasakbumi was reported to have chemopreventive effect. In cancer patients, there are some dysfunctions of blood parameter, therefore some hematologic tests are needed to monitor cancer patients. In this study, the effects of combination of ethanolic extract of E. longifolia Jack (EEE) and Dox on hematologic profiles were investigated in rats injected by DMBA. Rats were divided into eight groups. Group I was normal group; Group II, rats were treated with extract dose 100 mg/kgbw; Groups III, IV, V, VI, VII and VIII, rats were treated with Dox, DMBA, DMBA+Dox, DMBA+EEE, DMBA+Dox +EEE, and Dox+EEE, respectively. DMBA administration orally was conducted twice a week for 5 weeks. At 16th week of treatments, bloods were taken from orbitalis sinus for hematologicals profile (levels of Hb, erytrocyte, hematocrite, leukocyte, MCV, MCH, and differencial leucocyte count) measurements. These data were analyzed by one way ANOVA followed by LSD test. DMBA administration significantly decreased the hematological profiles compared to the normal group, except in lymphocyte level. Rats treated with extract and extract+Dox were able to increase the hematological profile compared to rats given by DMBA only. Based on these findings it can be concluded that the combination of EEE and Dox potentially increase hematological profile of rats given by DMBA.

Abstract 1049: Combinatorial effects of thymoquinone on the anticancer activity of doxorubicin in adult T-cell leukemia

Abstract Doxorubicin (Dox) is a clinically approved drug which suffers from drug resistance and cardiotoxicity. Recent studies have shown that thymoquinone (TQ) in combination with Dox can reduce Dox toxic side effects in vitro as well as in vivo. Both TQ and Dox have shown promising anticancer effects against aggressive adult T-cell leukemia (ATL), however, the anticancer potential of TQ and Dox combination treatment has never been tested against ATL. We hypothesized that co-treatment with TQ could enable the use of lower doses of Dox to achieve similar or enhanced anticancer activity. The effects of TQ and Dox combination on cell death and cell cycle were evaluated by trypan blue and propidium iodide. TUNEL assay was used to investigate the mode of cell death. The levels of reactive species (ROS) were determined using DCFH assay, and mitochondrial membrane potential was measured by rhodamine assay. The regulation of key proteins involved in cell cycle regulation and cell death was determined by Western blot. The results reveal that the human T-lymphotropic virus (HTLV-1) positive HuT-102 cells are more resistant to treatment with Dox alone, than the HTLV-1 negative Jurkat cells. However, treatment with high doses of TQ and low doses of Dox simultaneously, enhances cell death in both cancer cell lines as compared to treatment with Dox alone. TUNEL assay on Jurkat and HuT-102 cells further indicated that the combination of TQ and Dox caused cell death by apoptosis. An increase in ROS production was noted in response to treatment with TQ alone and with TQ and Dox combination in both Jurkat and HuT-102 cells. The oxidative stress; however, was only shown to play a role in the disruption of the mitochondria of Jurkat cells. Similarly, caspase activation was involved in the disruption of the mitochondria of Jurkat cells. The expression levels of key regulatory proteins were modulated in response to treatment with the combination. In conclusion, the combination of TQ and Dox effectively inhibits ATL leukemic cancer cell growth at lower doses of Dox which can potentially lower the side effects of the drug. In vivo studies are still warranted to assess the adjuvant chemotherapeutic potential of TQ in combination with Dox. Citation Format: Hala Gali-Muhtasib, Isabelle Fakhoury, Maamoun Fatfat, Rasha Mismar, Regine Schneider-Stock. Combinatorial effects of thymoquinone on the anticancer activity of doxorubicin in adult T-cell leukemia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1049. doi:10.1158/1538-7445.AM2017-1049

Abstract LB-308: KPT-9274 inhibits cellular NAD and synergizes with doxorubicin to treat dogs with lymphoma

Abstract Nicotinamide adenine dinucleotide (NAD), an essential metabolite and cofactor of several biological processes (e.g. genomic stability), undergoes significant alterations during malignant transformation. In cancer cells, the high metabolic demands of proliferating cells and increased activity of NAD consuming enzymes (i.e. SIRT1 and PARP1) lead to rapid NAD turnover. NAD can be generated de novo from tryptophan or regenerated by nicotinamide phosphoribosyl transferase (NAMPT) or nicotinate phosphoribosyl transferase 1 (NAPRT1) in NAD salvage pathways. However, cancer cells rely mainly on the NAMPT-dependent pathway, making NAD depletion a promising anti-cancer therapy. KPT-9274 is a novel first-in-class orally bioavailable dual inhibitor of p21-activated kinase 4 (PAK4) and NAMPT that demonstrates potent anti-tumor activity in a variety of cancer cell lines. KPT-9274 treatment rapidly depletes cellular NAD levels, leading to ATP loss and cell death. Similarly, hyper activation of PARP1 through DNA damaging agents (e.g. doxorubicin; DOX) can lead to apoptosis. Here we present results from a phase 1 study of KPT-9274 as a single agent and in combination with DOX for the treatment of dogs with solid tumors or lymphomas. Methods: Dogs with cancer (lymphoma, n=4; sarcoma n=6; mast cell tumor n=2) were enrolled into a prospective phase 1 dose escalation study of KPT-9274 given qod x 3 per week. Plasma samples were used for pharmacokinetics (PK) and tumor biopsies were used to assess pharmacodynamics (PDn; i.e. PAK4, NAMPT and downstream effectors). In an expansion cohort, dogs with lymphoma (n=6) received 4 doses of KPT-9274 at 2 mg/kg prior to administration of a single dose of DOX. Results: Doses up to 4 mg/kg KPT-9274 were well tolerated with no grade ≥3 toxicities. At 4.5 mg/kg one dog exhibited severe vomiting, diarrhea, collapse, anemia and thrombocytopenia, establishing 4 mg/kg as MTD. The PK of KPT-9274 was dose proportional and in agreement with healthy dogs. PDn markers (NAD levels) in tumors showed target engagement through NAD depletion as well as changes in PAK4 pathway biomarkers using IHC. Four dogs exhibited stable disease during treatment (3 soft tissue sarcomas, 1 mast cell tumor) at doses ranging from 3 - 4.5 mg/kg. Of the 6 dogs with naïve lymphoma that received KPT-9274 and a single dose of DOX, 5 achieved a complete response, one of which lasted for over 3 months. No unexpected toxicities were noted with the combination when compared to those expected from DOX alone. Conclusions: KPT-9274 exhibits single agent activity in canine spontaneous cancers. Moreover, the combination of KPT-9274 and DOX has substantial biologic activity against canine Non-Hodgkin lymphoma, likely through the activation of NAD consuming enzymes such as PARP1 by DOX. Importantly, the drug combination was safe with no enhanced toxicity over DOX alone. This data could be applied directly to the current trial of KPT-9274 in a Phase 1 clinical trial in patients with advanced solid malignancies or NHL (NCT02702492). Citation Format: Cheryl London, Megan Brown, Emma Warry, Elizabeth Schuh, William T. Senapedis, Christian Argueta, Trinayan Kashyap, Hua Chang, Joel Ellis, Sharon Shacham, Erkan Baloglu. KPT-9274 inhibits cellular NAD and synergizes with doxorubicin to treat dogs with lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-308. doi:10.1158/1538-7445.AM2017-LB-308

Inhalable bioresponsive chitosan microspheres of doxorubicin and soluble curcumin augmented drug delivery in lung cancer cells

In present investigation, doxorubicin (Dox) and soluble curcumin (Cur-2-HP-β-CD-complex) combination was simultaneously loaded in inhalable bioresponsive chitosan microspheres (Dox/Cur-2-HP-β-CD-complex-elastin-CMs) bearing a substrate-stimuli, elastin. The mean particle size and mean aerodynamic diameter of inhalable bioresponsive microspheres displayed noteworthy differences after incorporation of elastin. Moreover, combination of Dox and soluble curcumin was molecularly dispersed in microspheres matrix as substantiated by a range of spectral techniques. Inhalable bioresponsive microspheres released astonishingly higher amount of Dox in presence of elastase enzyme at pH∼5.5 in comparison to pH∼7.4. However, the release of soluble curcumin from tailored bioresponsive microspheres in presence of elastase enzyme was independent of pH. Consistently, inhalable bioresponsive microspheres exhibited outstandingly lower IC50 of 3.4-μM in comparison to 6.5-μM of inhalable drug loaded microspheres (Dox/Cur-2-HP-β-CD-complex-CMs) bearing no elastin, against A549, non-small cell lung cancer cells. The superior therapeutic profile of inhalable bioresponsive microspheres may be attributed to enhanced drug release and consequently augmented drug exposure to A549 cells expressing elastase enzyme. In this way, stimuli triggered drug release from tailored inhalable bioresponsive microspheres boosted the phenomena of apoptosis in A549 cells. In conclusion, Dox/Cur-2-HP-β-CD-complex-elastin-CMs warrant further in-vivo tumor regression study to prove its therapeutic efficacy.

Emodin: One Main Ingredient of Shufeng Jiedu Capsule Reverses Chemoresistance of Lung Cancer Cells Through Inhibition of EMT

Background: Chemoresistance has become a an important worldwide problem to cancer treatment. Understanding the mechanism of drug resistance is the key to solve this problem and improve the survival of the patient. Doxorubicin and its analogues are widely used as antitumor drugs but many doxorubicin resistant cases have been identified in recent years. Doxorubicin (Dox) resistance is a very serious phenomenon in lung cancer treatment. As we could show previously, Shufeng Jiedu Capsule (SFJDC) can effectively reverse H69AR cells resistance to Dox, thus, the present study was designed to explore the mechanism underlying the effects of the main ingredient Emodin on chemosensitivity of H69AR cells to Dox. Methods: First, the growth inhibition rate of lung cancer cells and normal bronchial epithelial cells (BECs) was determined by MTT. Then, the resistance-induced epithelial-mesenchymal transition (EMT) of H69AR cells was examined by western blot and the effect of Emodin on Twist, Snail or Slug was assayed by Real-time PCR and Western blot. The activation of NF-kappa B was assayed by Western blot. Proliferation, apoptosis, migration and invasion of H69AR cells induced by Twist, Snail and Slug were also assayed by flow cytometry and transwell chamber. Results: The results showed that after administration of Dox (10µM) with different concentrations of Emodin, the cells exhibited a dose-dependent inhibition action to H69AR cells at 48 hours. H69AR induced the expression of Twist, Snail, and Slug when compared with Dox-sensitive H69 cells. The expression of Twist, Snail, and Slug can be effectively inhibited by combination of Dox and Emodin. The reversal of resistance was associated with the inhibition of NF-kappa B. Twist, Snail and Slug promoted proliferation, migration and invasion and inhibited apoptosis. Conclusion: Our data suggest that Emodin can effectively reverse the resistance of H69AR to Dox, an effect paralleled by inhibition of EMT, cell proliferation, apoptosis, migration and invasion.

Apoferritin Nanocage Delivers Combination of Microtubule and Nucleus Targeting Anticancer Drugs.

An ideal nano drug delivery agent must be potent enough to carry high dose of therapeutics and competent enough in targeting specific cell of interest, having adequate optimized physiochemical properties and biocompatibility. Carrying differentially polar therapeutics simultaneously will make them superior in their class. However, it is of enormous challenge to the researchers to find such a unique nanocarrier and to engineer all of the above-mentioned features into it. In this manuscript, we have shown for the first time that apoferritin (Apf) can carry and deliver high dose of doxorubicin (Dox), docetaxel (Doc), and combination of both Dox and Doc specifically into the cancer cell and enhances killing compared to free drug without any functionalization or property modulation. In addition, we have shown that Apf alone is noncytotoxic in nature and interacts with intracellular tubulin/microtubule. Drug loaded Apf specifically bound and consequently internalized into the human breast cancer cell line (MCF7) and human cervical cancer cell line (HeLa) through receptor mediated endocytosis process and releases either single or combination of drugs in the endosome. We have also checked the binding efficacy of both drugs using molecular docking. Further, using fluorescence microscopy, we have shown that Apf can deliver combination of drugs inside cancer cells and the drugs exerts their effect thereof. Finally, we have studied the efficacy of Apf complexes with individual drugs and in combination compared to free drugs in a tumor mimicking 3D multicellular spheroid model of HeLa cell.

Lipid-coated hollow mesoporous silica nanospheres for co-delivery of doxorubicin and paclitaxel: Preparation, sustained release, cellular uptake and pharmacokinetics

A carrier consisting of lipid-coated hollow mesoporous silica nanospheres (L-HMSN) was produced for the combination of the water-insoluble drug (paclitaxel, PTX) and the water-soluble drug (doxorubicin, DOX). DOX was adsorbed into the nanoscale hollow structure of the hollow mesoporous silica nanospheres (HMSN) by adsorption and PTX was wrapped in the phospholipid layer of the HMSN surface by lipid film hydration method. The characterization results showed that DOX and PTX were present in the nanopheres in an amorphous state. The loaded L-HMSN (DOX/PTX@L-HMSN) in vitro drug release showed a sustained release in phosphate buffered solution (PBS) at pH6.8 and 0.001%SDS. The cellular uptake experiment indicated that L-HMSN was successfully taken up by A549 cells. In addition, the combination of DOX and PTX in L-HMSN exhibited a marked synergistic effect in inhibiting the proliferation of A549 cells. The pharmacokinetic study demonstrated that L-HMSN could significantly improve the relative bioavailability of DOX and PTX. These results confirm that L-HMSN is a promising carrier for successful drug combination.

Codelivery of thioridazine and doxorubicin using nanoparticles for effective breast cancer therapy.

Cancer chemotherapy can benefit from the combination of different anticancer drugs. Here, we prepared doxorubicin (Dox)- and thioridazine (Thio)-coloaded methoxy poly(ethylene glycol)-poly(l-lactic acid) (MPEG-PLA) nanoparticles (NPs) for breast cancer therapy. These NPs have an average particle size of 27 nm. The drug loading efficiencies of Thio and Dox are 4.71% and 1.98%, respectively. Compared to the treatment of Thio or Dox alone, the combination of Thio and Dox exhibited a synergistic effect in inhibiting the growth of 4T1 breast cancer cells in vitro. In addition, the Thio- and Dox-coloaded MPEG-PLA NPs could efficiently suppress the growth of breast cancer cells in vivo. This study suggests that Thio- and Dox-coloaded MPEG-PLA NPs might have potential applications in breast cancer treatment.

(Invited) Microfluidic Synthesis of Functional Nanomaterials

The controlled synthesis of functional nanoparticles with tunable structures and properties has been extensively investigated for cancer treatment and diagnosis. Among a variety of methods for fabrication of nanoparticles, microfluidics-based synthesis enables enhanced mixing and precise fluidic modulation inside microchannels, thus allowing for the flow-mediated production of nanoparticles in a controllable manner. We present a hollow-structured rigid nanoparticle fabricated by a multi-stage microfluidic chip in one step, to effectively entrap various hydrophilic reagents inside, without complicated synthesis, extensive use of emulsifiers and stabilizers, and laborious purification procedures. The nanoparticle contains a hollow water core, a rigid poly (lactic-co-glycolic acid) (PLGA) shell, and an outermost lipid layer. The entrapment efficiency of hydrophilic reagents such as calcein, rhodamine B and siRNA inside hollow water core is ~ 90 %. In comparison with the combination of free Dox and siRNA, the hollow-structured rigid nanoparticle that co-encapsulates siRNA and doxorubicin (Dox) reveals a significantly enhanced anti-tumor effect for a multi-drug resistant tumor model. Lipid-covered PLGA NPs or liposomes of the same size and surface properties, but different rigidity by controlling the interfacial water layer, can be realized using a two-stage microfluidic chip. It enables us to explore how rigidity of NPs regulates the cellular uptake and elucidate the intrinsic mechanism. Given the only significant difference between those two types of NPs is the rigidity, the experiments suggest that rigidity could dramatically alter the cellular uptake efficiency, with rigid NPs being easier to get through members than soft ones. The mechanisms revealed here suggest that tuning of rigidity of NPs is one appealing way in improving therapeutic efficiency.

Active targeting co-delivery system based on pH-sensitive methoxy-poly(ethylene glycol)2K-poly(ε-caprolactone)4K-poly(glutamic acid)1K for enhanced cancer therapy

In this paper, we successfully synthesized folate-modified pH-sensitive copolymer methoxy-poly(ethylene glycol)2K-poly(ε-caprolactone)4K-poly(glutamic acid)1K (mPEG2K-PCL4K-PGA1K-FA), which could form the polymeric assembly in an aqueous solution, for co-delivering hydrophilic drugs doxorubicin hydrochloride (DOX) and verapamil hydrochloride (VER) (FA-poly(DOX+VER)). Since VER was an effective P-glycoprotein inhibitor, the combination of DOX and VER could reverse the multidrug resistance efficiently and enhance the therapeutic effect. Therefore, the inhibition ratios of MCF-7/ADR resistant cancer cell treated by FA-poly (DOX+VER) were almost more than 30% higher than those of FA-polyDOX after 48h and 72h. Furthermore, the conjugation of FA could lead the co-delivery systems actively targeting into the FA receptor over-expressing cancer cells in addition to the passive accumulation of the assembly in tumor tissues. Importantly, the prepared mPEG2K-PCL4K-PGA1K-FA assembly showed high pH-sensitive property, which made the drugs mostly released in tumor tissue (acid environment) than in physiological environment (neutral environment). In summary, the as-prepared co-delivery system FA-poly(DOX+VER) demonstrated a high efficiency in reversing the multidrug resistance and targeting FA receptor to improve the anticancer effect of DOX in MCF-7/ADR resistant cells.

Doxorubicin hydrochloric increases tumour coagulation and end-point survival in percutaneous microwave ablation of tumours in a VX2 rabbit tumour model

Purpose: The aim of this study was to explore whether doxorubicin hydrochloric (DOX) combined with microwave ablation (MWA) is more effective at increasing tumour coagulation and prolonging end-point survival in a VX2 rabbit breast cancer model than each intervention individually.Methods: New Zealand white rabbits with VX2 tumours were placed into treatment groups as follows: MWA (20 W for 5 min and 40 W for 5 min), intravenous injection of 4 mg/kg DOX, and combined therapy. Tumours were analysed at 4 h and 24 h after treatment to determine the temporal quantities of cleaved caspase-3 and Hsp70 using immunohistochemical staining and Western blots. Tumour coagulation areas were compared at 24 h after treatment.Results: No significant difference in tumour coagulation was found between DOX-MWA and 40W-MWA (mean 4.52 cm2 ± 0.48 (SD), 4.08 cm2 ± 0.36, respectively; P > 0.05). A significant difference between tumour coagulation was found for DOX-MWA and 20W-MWA (mean 4.52 cm2 ± 0.48 (SD), 1.69 cm2 ± 0.34 cm2, respectively; p < 0.01). Cleaved caspase-3 and Hsp70 demonstrated low level expression at 4 h and 24 h in the DOX group. Cleaved caspase-3 showed low expression at the coagulation margin in the 20W-MWA group, was highly expressed in DOX-MWA group, and continued to increase with time. Hsp70 in the 20W-MWA group increased significantly at the coagulation margin but demonstrated low expression in the DOX-MWA group at 4 h and 24 h. The animals in the combined treatment group had a longer survival time (mean 78.33 days ± 8.07 SD) than the 20W-MWA group (mean 57.17 days ± 8.77, p < 0.01) or the DOX group (mean 35.17 days ± 7.63, p < 0.01).Conclusion: A combination of DOX and MWA could increase tumour coagulation and end-point survival better than single therapy, which had some connection with the elevated expression of cleaved caspase-3 and low Hsp70 expression at the coagulation margin.

Assessment of DNA damage in Ehlrich carcinoma after treatment with doxorubicin encapsulated in nanoscales thermosensitive liposomes in combination with localized hyperthermia.

Nanoscales thermosensitive liposomes (TSL) composed of synthetic lipids (dipalmitoylphosphatidylcholine, and distearoylphosphatidylcholine), were used for doxorubicin encapsulation with 70% encapsulated efficiency. The liposomes were characterized by dynamic light scattering, transmission electron microscopy and turbidity method. Additionally, the liposomes exhibited a significant release of doxorubicin (Dox) by 60% within 5 min at 42°C. To assess the therapeutic efficacy of Dox in combination with hyperthermia, Dox free and encapsulated TSL were administered directly to Ehrlich tumor bearing mice at 1 mg/kg dose. Immediately after the drug administration, hyperthermia was applied to mention the temperature inside the tumor site at 42°C either for 5 min and 30 min. The results indicate a significant increase in the percent of apoptotic and necrotic cells in the treated group. Moreover, disrupts the integrity and the amount of intact DNA in tumor cells. In conclusion, Dox and hyperthermia may serve as a useful targeted drug delivery system for management of Ehrlich carcinoma.

Quercetin Increase the Chemosensitivity of Breast Cancer Cells to Doxorubicin Via PTEN/Akt Pathway.

Our previous study indicated that nontoxic doses of quercetin (Que) could increase the chemosensitivity of breast cancer cells to doxorubicin (Dox) although the mechanism still remains elusive. Therefore, in this study, we aimed to investigate the underlying mechanisms. MCF-7 cells and MCF-7/dox cells were exposed to PTEN inhibitor bpV (HOpic), Dox, or combination of Dox and Que with or without bpV (HOpic) intervention for 24 hours. Cell proliferation, cell apoptosis, cell invasion and expression of PTEN and phospho-Akt (p-Akt) were then assessed. bpV (HOpic) had little effect on cell proliferation at concentrations less than 1 μM. Compared to treatment with Dox alone, combined treatment with Dox and Que significantly inhibited cell proliferation and invasion, increased cell apoptosis, up-regulated the expression of PTEN and down-regulated the expression of p-Akt. However, co-treatment with PTEN inhibitor bpV (HOpic) could revert the effects of Que on Dox. These data indicate that Que can increase the sensitivity of breast cancer cells to Dox through down regulation of p-Akt expression arising from increased expression of PTEN.

Abstract 2554: Doxorubicin induced gender differences in tumor-bearing spontaneously hypertensive rats, with an emphasis on cardiotoxicity

Abstract Treatment of cancer with anthracyclines such as doxorubicin (Dox) causes dose-limiting cardiotoxicity, particularly in younger females and adult males. However, the exact reason for gender differences in toxicity is unclear. Dox metabolites prompt the generation of excess reactive oxygen species (ROS) using an iron-mediated mechanism in the mitochondria. Cardiomyocytes, in addition to having lower levels of antioxidant enzymes also have higher concentrations of mitochondria and are therefore hypersensitive to ROS. In this study, we investigated the role of gender in Dox induced cardiotoxicity using male, castrated male (c-male), female and ovariectomized female (o-female) adult spontaneously hypertensive rats (SHRs). The SHRs were implanted with a syngeneic breast cancer cell line previously derived from SHRs. Tumor-bearing SHRs were treated with saline, Dox (10 mg/kg iv), dexrazoxane [(50 mg/kg ip) Drz], or a combination of both Dox and Drz. Tumor size was used to monitor anticancer activity. In all genders, the addition of Dox (alone or in combination with Drz) induced a significant reduction in tumor volume. Addition of Dox (or Dox + Drz) also caused an increase in the heart:body weight ratio for all genders. Histopathological analyses of cardiac sections treated with Dox showed higher heart lesion scores in males than c-males, females, or o-females. We are currently analyzing serum cardiac troponin T, estradiol and testosterone levels for correlation with histopathology. Preliminary findings suggest that sex hormones (estradiol and testosterone) may be influenced by Dox induced cardiotoxicity and may be important in the mode of action of this therapy. After Dox treatment, gene expression analysis of mitochondria-related genes showed increased expression levels in pro-apoptotic genes in both females and, to a greater extent, males. Genes associated with oxidative stress responses also showed a significant increase in male hearts. Our data indicate that adult male SHR hearts were more sensitive to Dox treatment than other genders. Sex hormone levels may influence cardiotoxicity, since Dox treated SHRs for all genders had little to no testosterone or estradiol. Overall, our findings demonstrate Dox induced cardiotoxicity is gender specific and adult males are more cardiosensitive than other genders. The mechanism behind Dox induced cardiotoxicity is currently being elucidated and likely functions, at least in adult male SHRs, through the induction of oxidative stress and expression of apoptotic genes and is inversely correlated to sex hormone levels. Citation Format: Kaytee L. Pokrzywinski, Yanira Gonzalez, Leena M. Chehab, Elliot T. Rosen, Vikrant Vijay, Varsha Desai, Jennifer S. Dickey, V. Ashutosh Rao. Doxorubicin induced gender differences in tumor-bearing spontaneously hypertensive rats, with an emphasis on cardiotoxicity. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2554. doi:10.1158/1538-7445.AM2015-2554

Coadministration of doxorubicin and etoposide loaded in camel milk phospholipids liposomes showed increased antitumor activity in a murine model.

Small unilamellar vesicles from camel milk phospholipids (CML) mixture or from 1,2 dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) were prepared, and anticancer drugs doxorubicin (Dox) or etoposide (ETP) were loaded. Liposomal formulations were used against fibrosarcoma in a murine model. Results showed a very high percentage of Dox encapsulation (~98%) in liposomes (Lip) prepared from CML-Lip or DPPC-Lip, whereas the percentage of encapsulations of ETP was on the lower side, 22% of CML-Lip and 18% for DPPC-Lip. Differential scanning calorimetry curves show that Dox enhances the lamellar formation in CML-Lip, whereas ETP enhances the nonlamellar formation. Differential scanning calorimetry curves also showed that the presence of Dox and ETP together into DPPC-Lip produced the interdigitation effect. The in vivo anticancer activity of liposomal formulations of Dox or ETP or a combination of both was assessed against benzopyrene (BAP)-induced fibrosarcoma in a murine model. Tumor-bearing mice treated with a combination of Dox and ETP loaded into CML-Lip showed increased survival and reduced tumor growth compared to other groups, including the combination of Dox and ETP in DPPC-Lip. Fibrosarcoma-bearing mice treated with a combination of free (Dox + ETP) showed much higher tumor growth compared to those groups treated with CML-Lip-(Dox + ETP) or DPPC-Lip-(Dox + ETP). Immunohistochemical study was also performed to show the expression of tumor-suppressor PTEN, and it was found that the tumor tissues from the group of mice treated with a combination of free (Dox + ETP) showed greater loss of cytoplasmic PTEN than tumor tissues obtained from the groups of mice treated with CML-Lip-(Dox + ETP) or DPPC-Lip-(Dox + ETP).

Microfluidic Synthesis of Rigid Nanovesicles for Hydrophilic Reagents Delivery

AbstractWe present a hollow‐structured rigid nanovesicle (RNV) fabricated by a multi‐stage microfluidic chip in one step, to effectively entrap various hydrophilic reagents inside, without complicated synthesis, extensive use of emulsifiers and stabilizers, and laborious purification procedures. The RNV contains a hollow water core, a rigid poly (lactic‐co‐glycolic acid) (PLGA) shell, and an outermost lipid layer. The formation mechanism of the RNV is investigated by dissipative particle dynamics (DPD) simulations. The entrapment efficiency of hydrophilic reagents such as calcein, rhodamine B and siRNA inside the hollow water core of RNV is ≈90 %. In comparison with the combination of free Dox and siRNA, RNV that co‐encapsulate siRNA and doxorubicin (Dox) reveals a significantly enhanced anti‐tumor effect for a multi‐drug resistant tumor model.