Acetylamine derivative of diospyrin, a plant-derived binaphthylquinonoid, inhibits human colon cancer growth in Nod-Scid mice.

Anticancer activity of diospyrin and its derivatives (1-5) was evaluated against thirteen human cell lines. Compared to diospyrin (1), the acetylamine derivative (4) exhibited increase in cytotoxicity, particularly in HT-29 colon cancer cells, showing GI50 values of 33.90 and 1.96 µM, respectively. Also, enhanced toxicity was observed when cells, pre-treated with compound 4, were exposed to radiation. In vivo assessment of 4 was undertaken on tumour-bearing Nod-Scid mice treated at 4 mg/kg/day. Significant reduction in relative tumour volume (~86-91 %) was observed during the 12th-37th days after drug treatment. Increased caspase-3 activity and DNA ladder formation was observed in HT-29 cells after treatment with 4, suggesting induction of apoptotic death after drug treatment. Moreover, flow cytometric determination of Annexin V- FITC positive and PI negative cells demonstrated 17.4, 26.4, and 27.9 % of early apoptosis, respectively, upon treatment with 5, 10 and 25 µM of 4. HT-29 cells after treatment with 4 (1-25 µM) revealed ~2.5- 3- folds generation of ROS. Furthermore, concentration dependent decrease of mitochondrial trans-membrane potential (∆ψm), and expression of Bcl-2/Bax and other marker proteins suggested involvement of mitochondrial pathway of cell death. Overall, our results demonstrated the underlying cell-death mechanism of the plant-derived naphthoquinonoid (4), and established it as a prospective chemotherapeutic 'lead' molecule against colon cancer.

Enhanced thorium decorporation and mitigation of toxicity through combined use of Liv52® and diethylenetriamine pentaacetate.

Thorium-232 (Th-232) is a promising fuel for advanced nuclear reactors. However, in case of internal human exposure to Th, there is currently no effective modality for its removal from liver and skeleton or for mitigating its effect. The FDA-approved agent, diethylenetriaminepentaacetate (DTPA), can remove Th and other actinides from blood circulation only. For the first time, a rationally-selected polyherbal hepatoprotective i.e. Liv52® (L52S), was evaluated in-combination with DTPA for its Th decorporation ability in Swiss mice. Inductively-coupled plasma mass spectroscopic analysis showed that oral administration of L52S in conjunction with DTPA significantly decreased Th burden from liver (20 %) and skeleton (33 %) as well as enhanced Th excretion (∼2.5 folds) through urine in comparison to DTPA or L52S alone. The combinatorial therapy was found to be complementary in-action, ameliorating Th-induced tissue damage in liver, spleen, and bone more effectively than monotherapy. Furthermore, markers of liver function (alanine transaminase) and liver inflammation and fibrosis (NF-κB & keratin) further validated the beneficial effect of L52S. The human consumption of L52S for various liver disorders further supports its clinical application for Th decorporation and mitigation of its health effects.

Cytokine profile of conditioned medium from human tumor cell lines after acute and fractionated doses of gamma radiation and its effect on survival of bystander tumor cells.

Cytokines are known to play pivotal roles in cancer initiation, progression and pathogenesis. Accumulating evidences suggest differences in basal and stress-induced cytokine profiles of cancers with diverse origin. However, a comprehensive investigation characterising the cytokine profile of various tumor types after acute and fractionated doses of gamma-irradiation, and its effect on survival of bystander cells is not well known in literature. In the present study, we have evaluated the cytokine secretion profile of human tumor cell lines (HT1080, U373MG, HT29, A549 and MCF-7) either before (basal) or after acute (2, 6 Gy) and fractionated doses (3×2 Gy) of gamma-irradiation in culture medium obtained from these cells by multiplex bead array/ELISA. Moreover, clonogenic assays were performed to evaluate the effect of conditioned medium (CM) on the survival and growth of respective cells. Based on the screening of 28 analytes, our results showed that the basal profiles of these cell lines varied considerably in terms of the number and magnitude of secreted factors, which was minimum in MCF-7. Interestingly, TNF-α, IL-1ß, PDGF-AA, TGF-ß1, fractalkine, IL-8, VEGF and GCSF were found in CM of all the cell lines. However, secretion of certain cytokines was cell line-specific. Moreover, CM caused increase in clonogenic survival of respective tumor cells (in the order HT1080>U373MG>HT29>A549>MCF-7), which was correlated with the levels of IL-1ß, IL-6, IL-8, GMCSF and VEGF in their CM. After irradiation, the levels of most of the cytokines increased markedly in a dose dependent manner. The fold change in cytokine levels was lower in irradiated conditioned medium (ICM) of tumor cells collected after fractionated than respective acute dose, except in MCF-7. Interestingly, amongst these cell lines, the radiation-induced fold increase in cytokine levels was maximum in ICM of A549 cells. Moreover, bystander A549 cells treated with respective ICM showed dose dependent decrease in clonogenic survival. In conclusion, present study revealed the similarities and subtle differences in basal and radiation-induced cytokine profile of different tumor cell lines, and its influence on growth and survival of respective bystander cells. These findings may add a new dimension to our current understanding about role of cytokines in cancer biology.

Development of surface functionalized hydroxyapatite nanoparticles for enhanced specificity towards tumor cells.

Nanoparticles coupled with targeting moieties have attracted a great deal of attention for cancer therapy since they can facilitate site-specific delivery of drug and significantly limit the side effects of systemic chemotherapy. In this study, our aim is to develop surface functionalized hydroxyapatite nanoparticles, which could provide binding sites for a cancer cell targeting ligand, folic acid (FA) as well as an anticancer drug, doxorubicin hydrochloride (DOX). In order to attain dual functionalities, hydroxyapatite nanoparticles were functionalized with gelatin molecules. Gelatin, being a protein has both carboxyl and amine moieties, which makes it suitable for binding of DOX and FA. FA was chemically conjugated to the nanoparticles through an EDCNHS coupling reaction. The formation of single-phase hydroxyapatite nanostructure was ascertained by X-ray diffraction studies and the presence of organic moieties on the surface of nanoparticles was evident from Fourier transform infrared spectroscopy, thermogravimetric analysis and U.V.-visible spectroscopy. The FA-conjugated nanoparticles (FA-Gel-HANPs) showed high affinity towards DOX and pH-responsive sustained release of drug with higher release rate under acidic pH conditions, desired for cancer therapy. The FA-Gel-HANPs showed negligible cytotoxicity towards different cell lines (HepG2, WEHI-164, KB, WI-26 VA4 and WRL-68). However, DOX loaded nanoparticles (DOX-FA-Gel-HANPs) exhibited significant toxicity towards these cells, which was however highest in folate receptor (FR)-overexpressing, KB cells. These results were correlated with enhanced cellular uptake of DOX-FA-Gel-HANPs in KB cells in comparison to FR-deficient, WRL-68 cells studied by confocal laser scanning microscopy and flow cytometry. Moreover, cell cycle analysis in KB cells, showed higher sub-G1 population, indicating apoptosis as one of the cell death mechanisms. Overall, this study suggests that DOX-FA-Gel-HANPs could serve as a promising tumor-targeted drug delivery system.

Glutamic acid-coated Fe3O4 nanoparticles for tumor-targeted imaging and therapeutics.

We have developed surface functionalised Fe3O4 magnetic nanoparticles (MNPs) based system that can be used for tumor-targeted multimodal therapies and MR imaging. Biocompatible, non-essential amino acid (glutamic acid) was introduced onto the surface of Fe3O4 MNPs to provide functional sites for binding of chemotherapeutic drugs. These glutamic acid-coated Fe3O4 MNPs (GAMNPs) exhibit good water-dispersibility, magnetic responsivity and pH dependent charge conversal feature. The magnetic core as well as organic shell of GAMNPs was characterized by XRD, TEM, DLS, FTIR, PPMS and UV-visible spectroscopy and zeta-potential analyzer etc. The broad spectrum anticancer drugs, doxorubicin hydrochloride (DOX) and methotrexate (MTX) were electrostatically and covalently conjugated to the surface of GAMNPs, respectively for combination chemotherapy. These dual drugs loaded system (DOX-MTX-GAMNPs) shows pH dependent release behaviour of both the drugs and enhanced toxicity towards breast cancer cell line (MCF-7) as compared to their individual treatment. Fluorescence microscopy and flow cytometric analyses confirmed the successful uptake of drug loaded system into MCF-7 cell lines. Further MTX being analogue of folic acid, its co-delivery with DOX would help in internalization of both the drugs into MCF-7 cells. These GAMNPs also show good heating efficiency under AC magnetic field (Intrinsic loss power, ILP = 0.95 and 0.73 and 0.48 nHm2/Kg at Fe concentration of 0.5, 1 and 2 mg/ml, respectively) and transverse relaxivity (r2 = 152 mM-1 s-1) indicating their potential capability for hyperthermia therapy and MRI tracking. Furthermore, it has been observed that the combination of chemotherapeutic drugs and hyperthermia leads to an enhancement of cytotoxicity in MCF-7 cells.

Role of mitochondrial oxidative stress in the apoptosis induced by diospyrin diethylether in human breast carcinoma (MCF-7) cells.

Mitochondria and associated oxidative stress have been shown to play critical roles in apoptotic death induced by various stress agents. Previously, we reported the antitumor property of diospyrin (D1), a plant-derived bisnaphthoquinonoid, and its diethylether derivative (D7), which was found to cause apoptotic death in human cancer cell lines. The present study aims to explore the relevant mechanism of apoptosis involving generation of cellular reactive oxygen species (ROS) by D7 in human breast carcinoma (MCF-7) cells. It was found that while D7 inhibited the proliferation of tumor cells, the associated apoptosis induced by D7 was prevented by treating the cells with N-acetyl-L-cysteine (NAC), an antioxidant, and cyclosporine A (CsA), an inhibitor of mitochondrial permeability transition (MPT). Experiments using suitable inhibitors also demonstrated that D7 could alter the electron flow in mitochondrial electron transport chain by affecting target(s) between complex I and complex III, and indicated the probable site of D7-induced generation of ROS. These results were further supported by confocal microscopic observation on changes in mitochondrial organization and shape in cells treated with D7. Taken together, the results of our study clearly suggested that the apoptosis induced by D7 would involve alteration of MPT, cardiolipin peroxidation, migration of Bax from cytosol to mitochondria, decreased expression of Bcl-2, and release of cytochrome c, indicating oxidative mechanism at the mitochondrial level in the tumor cells.

Thorium-induced neurobehavioural and neurochemical alterations in Swiss mice.

PURPOSE: Thorium ((232)Th), a heavy metal radionuclide that targets the liver and skeleton, has been shown to accumulate in the central nervous system at low levels. The present study was aimed to investigate neurobehavioural and neurochemical changes in mice treated with (232)Th at sub-lethal doses. MATERIALS AND METHODS: Swiss albino mice were administered intraperitoneally with thorium nitrate. The chelation-based therapeutic effect of calcium diethylenetriamine pentaacetate (Ca-DTPA) was tested on the (232)Th-treated mice. (232)Th localisation was determined in brain regions by the Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) method. Achetylcholine esterase (AChE) activity in different brain regions was evaluated to assess the cholinergic function of mice CNS. Oxidative damage was evaluated by assessing the activities of antioxidant enzymes (i.e., superoxide dismutase and catalase) and the level of lipid peroxidation. The neurobehavioural alteration in the treated mice was studied by the shuttle box method. RESULTS: (232)Th accumulation found in different brain regions followed the order: Cerebellum (Cbl) > cortex (Ctx) > hippocampus (Hp) > striatum (Str). However, removal of (232)Th by Ca-DTPA was significant from brain regions like Cbl, Ctx and Str but not from Hp. A significant increase in lipid peroxidation and acetylcholine esterase (AChE) activity was observed in the treated mice but activities of superoxide dismutase and catalase was found substantially decreased. (232)Th treatment impaired the learning and memory-based neurobehaviour of the mice. Furthermore, our data suggest that Ca-DTPA injection in (232)Th-treated animals failed to improve the neurobehaviour of the treated mice, perhaps because Ca-DTPA could not decorporate (232)Th or mitigate (232)Th-mediated neurochemical changes effectively from/in hippocampus, a brain region implicated in learning and memory response. CONCLUSION: Administration of (232)Th in mice caused neurobehavioural alteration and impairment of cholinergic function, which might be the consequence(s) of oxidative stress induction in different brain regions.

Tumorsphere assay provides a better in vitro method for cancer stem-like cells enrichment in A549 lung adenocarcinoma cells.

Cancer stem cells (CSCs) have been implicated in growth, metastasis, recurrence and chemo-/radio-resistance in several cancer types. Despite a plenty of literature about different in vitro techniques to enrich/isolate CSCs, their comparative characterization for stemness is not well established. In the present study, cells obtained following three in vitro assays [clonogenic assay, tumorsphere assay (TSA) and single cell assay (SCA)] were compared for their cancer stem-like cell characteristics in human lung adenocarcinoma (A549) cells. Expression of the pluripotent (OCT4, NANOG) and lung cancer stem cell marker (CD166) genes were studied in these cells. Results showed that in comparison to cells obtained from routine culture (CC), the cells obtained from TSA showed significantly higher expression of OCT-4 and NANOG. These results were further validated with quantification of cell surface cancer stem cell markers i.e. CD44+/CD24- in the cells obtained from different methods, which were higher in TSA and SCA. Additionally, functional characterization of cancer stem-like cells (CSLCs) using ALDH assay showed the highest % of ALDH+ cells in TSA. These results were in agreement with higher resistance of these cells against 5-Fluorouracil suggesting higher fraction of CSLCs in TSA than the other assays. These results showed that TSA provides a better method to enrich CSLCs in A549 lung adenocarcinoma cells.

Increased cytotoxicity by the combination of radiation and diospyrin diethylether in fibrosarcoma in culture and in tumor.

OBJECTIVE: Radio-resistance in tumor cells and associated escape from apoptotic mechanism is a major problem in clinical cancer radiotherapy. Therefore, as a strategy to enhance the apoptosis, a combination of radiation and tumor-selective cytotoxic agents might improve the efficacy of treatment. Thus, the radiomodifying potential of diospyrin diethylether (D7), a plant-derived antitumor agent, was studied in fibrosarcoma tumor, both in vitro and in vivo. MATERIAL AND METHODS: Mouse and human fibrosarcoma (Wehi164; HT1080) cells were treated with D7, alone, or in combination with radiation, for determination of cytotoxicity, clonogenic survival, and apoptotic death assays. Involvement of oxidative mechanism and nuclear factor kappa B (NF-kappaB) was studied in different treatment groups. In addition, fibrosarcoma-bearing mice were treated with D7 (intravenously, two doses, each of 1 mg/kg body weight) combined with radiation (two fractions of 2.5 Gy each) at appropriate intervals. The tumor volume was measured to assess 'tumor growth delay', and liver function enzymes in the serum of mice were estimated after the treatments. RESULTS: A combination treatment with D7 and radiation showed enhancement in cytotoxicity and apoptotic induction and decrease in clonogenic survival of tumor cells, as compared to the treatments with the drug or radiation alone. Moreover, D7 in combination with radiation could significantly inhibit the radiation-induced NF-kappaB activation, and showed the generation of comparatively more intracellular reactive oxygen species (ROS). Similarly, a combination of D7 and radiation in vivo caused significant inhibition of tumor growth in vivo, and restoring the liver enzyme activity to the 'normal' level. CONCLUSION: The combined treatment with quinonoid D7 and radiation caused increased cytotoxicity compared to single treatment with either agent alone in fibrosarcoma tumor systems, both in vitro and in vivo.

Thorium-induced oxidative stress mediated toxicity in mice and its abrogation by diethylenetriamine pentaacetate.

PURPOSE: Thorium ((232)Th, IV) preferentially accumulates in the liver, femur and spleen, which necessitates evaluation of its toxic effect in these organs. The present study was aimed at evaluation of liver function, oxidative stress and histological alterations in these organs. MATERIALS AND METHODS: Swiss albino mice were administered either with Thorium nitrate (10 mg/kg body weight/day equivalent to 1,090 pCi/kg body weight/day) for 30 days (1/40th dose of LD(50/30); the dose of thorium required to kill 50% of the test cohort within 30 days) intraperitoneally or with calcium salt of diethylenetriamine pentaacetate (Ca-DTPA, 100 micromole/kg body/weight) intravenously or both. Liver function tests and oxidative damage was assessed. The concentration of Th in the tissues was determined by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) method. RESULTS: Administration of Th prevented the increase in the body and liver weight and altered liver functions. Th treatment to mice showed a decrease in the activities and gene expression of antioxidant enzymes, and increased lipid peroxidation and protein carbonylation. The extent of observed oxidative damage was correlated with accumulation of Th in examined organs and further associated with histological alterations. Furthermore it was found that these effects were significantly lower when the chelating agent, Ca-DTPA, was given 1 h after Th injection. CONCLUSION: Administration of subtoxic concentration of Th to mice markedly altered the liver functions and induced oxidative stress in the liver, femur and spleen of mice. The results further demonstrated that Ca-DTPA significantly protected mice against the toxic effects of Th.

Quantitative structure-activity relationship (QSAR) of N-arylsubstituted hydroxamic acids as inhibitors of human adenocarcinoma cells A431.

Hydroxamic acids the multifunctional molecules with general formula R'-C(=O)NROH have interesting medicinal and biological potentiality. The antiproliferative activity of 12 hydroxamic acids has been tested in vitro towards human adenocarcinoma cell line by MTT assay. The IC(50) values were found to be in the range from 12 to 152.8 microM. The most potent product identified is N-p-chlorophenyl-4-nitrobenzohydroxamic acid with IC(50) value 12 microM. The RP-HPLC experiment of these molecules was performed with 50:50(V)/(V) % methanol - water mixture as mobile phase. A QSAR is developed for the human adenocarcinoma cells inhibitory activity of a series of hydroxamic acids (n=1-12) that are structurally related to hydroxyurea. Multivariate analytical tool, projection to latent structures was used to develop a suitably predictive model for the purpose of optimizing and identifying members with more potent inhibitory activity. The cross- validated Q(2)cum values for two optimal PLS models of hydroxamic acids are above 0.690 (remarkably higher 0.500), indicating good predictive abilities for log1/IC(50) values of HAs. By partial least squares regression, two QSAR models revealed that, besides the essential pharmacophore - NOH.C=O, retention capacity factor, logk', polar surface area, PSA, Dipole moment, Dm, total no. of hydrogen bond donor and acceptor atoms, H, and chlorine atoms attached in upper or/and lower phenyl rings, I(Cl) , are important determinants for the inhibitory potency against A431 cells.

Synthesis and characterization of monodispersed water dispersible Fe3O4 nanoparticles and in vitro studies on human breast carcinoma cell line under hyperthermia condition.

Monodispersed Fe3O4 magnetic nanoparticles (MNPs) having size of 7 nm have been prepared from iron oleate and made water dispersible by functionalization for biomedical applications. Three different reactions employing thioglycolic acid, aspartic acid and aminophosphonate were performed on oleic acid coated Fe3O4. In order to achieve a control on particle size, the pristine nanoparticles were heated in presence of ferric oleate which led to increase in size from 7 to 11 nm. Reaction parameters such as rate of heating, reaction temperature and duration of heating have been studied. Shape of particles was found to change from spherical to cuboid. The cuboid shape in turn enhances magneto-crystalline anisotropy (Ku). Heating efficacy of these nanoparticles for hyperthermia was also evaluated for different shapes and sizes. We demonstrate heat generation from these MNPs for hyperthermia application under alternating current (AC) magnetic field and optimized heating efficiency by controlling morphology of particles. We have also studied intra-cellular uptake and localization of nanoparticles and cytotoxicity under AC magnetic field in human breast carcinoma cell line.

pH sensitive surfactant-stabilized Fe3O4 magnetic nanocarriers for dual drug delivery.

Highly water-dispersible surfactant-stabilized Fe3O4 magnetic nanocarriers (SMNCs) were prepared by self-assembly of anionic surfactant, sodium dodecyl sulphate (SDS) on hydrophobic (oleic acid coated) nanoparticles and their biomedical applications were investigated. These nanocarriers have an average size of about 10nm and possess tunable surface charge properties. The formation of an organic coating of SDS was evident from infrared spectroscopy, dynamic light scattering, zeta-potential and thermogravimetric measurements. These nanocarriers were used for loading of both hydrophilic and hydrophobic anticancer agents such as doxorubicin hydrochloride (DOX) and curcumin (CUR), respectively. DOX was conjugated onto the surface of nanocarriers through electrostatic interaction, whereas CUR was encapsulated into the hydrophobic interlayer between oleic acid and SDS. The toxicity and cellular internalization of drug loaded nanocarriers were investigated against WEHI-164 cancer cell line. Specifically, the drug loading, pH sensitive drug release and cellular internalization studies suggested that these nanocarriers are suitable for dual drug delivery. Furthermore, they show good heating ability under AC magnetic field, thus can be used as effective heating source for hyperthermia treatment of cancer.

Cytotoxicity of diospyrin and its derivatives in relation to the generation of reactive oxygen species in tumour cells in vitro and in vivo.

BACKGROUND: Alkyl ethers (D2 and D7) synthesized from diospyrin (D1), a naphthoquinonoid isolated from Diospyros montana Roxb., were evaluated for cytotoxicity and capacity to generate reactive oxygen species (ROS) in tumour cells. METHODS: The tumour inhibitory activity of the quinonoids was assessed in vivo against Ehrlich ascites carcinoma (EAC), while cytotoxicity was determined in vitro on EAC and MCF-7 cancer cells by MTT assay. ROS generated by quinonoids in MCF-7 cells was measured fluorimetrically. RESULTS: The tumour inhibitory activity, cytotoxicity and ROS generation capacity of quinonoids were found to be D7 > D2 > D1. CONCLUSION: Alkyl ethers of D1 were more cytotoxic against tumour cells in vitro as well as in vivo.

Potential of traditional ayurvedic formulation, Triphala, as a novel anticancer drug.

The cytotoxic effects of aqueous extract of Triphala, an ayurvedic formulation, were investigated on human breast cancer cell line (MCF-7) and a transplantable mouse thymic lymphoma (barcl-95). The viability of treated cells was found to decrease with the increasing concentrations of Triphala. On the other hand, treatment of normal breast epithelial cells, MCF-10 F, human peripheral blood mononuclear cells, mouse liver and spleen cells, with similar concentrations of Triphala did not affect their cytotoxicity significantly. The drug treatment was found to induce apoptosis in MCF-7 and barcl-95 cells in vitro as determined by annexin-V fluorescence and proportion of apoptotic cells was found dependent on Triphala concentration. MCF-7 cells treated with Triphala when subjected to single cell gel electrophoresis, revealed a pattern of DNA damage, characteristic of apoptosis. Studies on Triphala treated MCF-7 and barcl-95 cells showed significant increase in intracellular reactive oxygen species (ROS) in a concentration dependent manner. ROS increase was, however, found to be insignificant in MCF-10 F as well as in murine spleen and liver normal cells. In vivo, direct oral feeding of Triphala to mice (40 mg/kg body weight) transplanted with barcl-95 produced significant reduction in tumor growth as evaluated by tumor volume measurement. It was also found that apoptosis was significantly higher in the excised tumor tissue of Triphala fed mice as compared to the control, suggesting the involvement of apoptosis in tumor growth reduction. These results suggest that Triphala possessed ability to induce cytotoxicity in tumor cells but spared the normal cells. The differential effect of Triphala on normal and tumor cells seems to be related to its ability to evoke differential response in intracellular ROS generation. The differential response of normal and tumor cells to Triphala in vitro and the substantial regression of transplanted tumor in mice fed with Triphala points to its potential use as an anticancer drug for clinical treatment.

Protection against radiation oxidative damage in mice by Triphala.

Protection against whole body gamma-irradiation (WBI) of Swiss mice orally fed with Triphala (TPL), an Ayurvedic formulation, in terms of mortality of irradiated animals as well as DNA damage at cellular level has been investigated. It was found that radiation induced mortality was reduced by 60% in mice fed with TPL (1g/kg body weight/day) orally for 7 days prior to WBI at 7.5 Gy followed by post-irradiation feeding for 7 days. An increase in xanthine oxidoreductase activity and decrease in superoxide dismutase activity was observed in the intestine of mice exposed to WBI, which, however, reverted back to those levels of sham-irradiated controls, when animals were fed with TPL for 7 days prior to irradiation. These data have suggested the prevention of oxidative damage caused by whole body radiation exposure after feeding of animals with TPL. To further understand the mechanisms involved, the magnitude of DNA damage was studied by single cell gel electrophoresis (SCGE) in blood leukocytes and splenocytes obtained from either control animals or those fed with TPL for 7 days followed by irradiation. Compared to irradiated animals without administering TPL, the mean tail length was reduced about three-fold in blood leukocytes of animals fed with TPL prior to irradiation. Although, similar protection was observed in splenocytes of TPL fed animals, the magnitude of prevention of DNA damage was significantly higher than that observed in leukocytes. It has been concluded that TPL protected whole body irradiated mice and TPL induced protection was mediated through inhibition of oxidative damage in cells and organs. TPL seems to have potential to develop into a novel herbal radio-protector for practical applications.

Folic acid conjugated Fe3O4 magnetic nanoparticles for targeted delivery of doxorubicin.

The interfacial engineering of magnetic nanoparticles (MNPs) with specific functional groups or targeting ligands is important for their in vivo applications. We report here the preparation and characterization of bifunctional magnetic nanoparticles (BMNPs) which contain a carboxylic moiety for drug binding and an amine moiety for folate mediated drug targeting. BMNPs were prepared by introducing bioactive cysteine molecules onto the surface of undecenoic acid coated Fe3O4 magnetic nanoparticles (UMNPs) via a thiol-ene click reaction and then, folic acid was conjugated with these BMNPs through an EDC-NHS coupling reaction. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis indicate the formation of highly crystalline single-phase Fe3O4 nanostructures. The changes in the interfacial characteristics of the nanoparticles and the presence of an organic coating are evident from Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta-potential measurement, and thermogravimetric analysis (TGA). These nanocarriers have an average size of 10 nm, and have a pH dependent charge conversional feature and protein resistance characteristic in physiological medium. These nanoparticles also show high loading affinity for an anticancer drug, doxorubicin hydrochloride (DOX) and its pH dependent release. This is highly beneficial for cancer therapy as the relatively low pH in tumors will specifically stimulate the drug release at the site of interest. Furthermore, our fluorescence microscopy and flow cytometry studies confirmed the higher cellular internalization capability of these folic acid conjugated nanoparticles in cancer cells over-expressing folate receptors.

Molecular Understanding of Growth Inhibitory Effect from Irradiated to Bystander Tumor Cells in Mouse Fibrosarcoma Tumor Model.

Even though bystander effects pertaining to radiation risk assessment has been extensively studied, the molecular players of radiation induced bystander effect (RIBE) in the context of cancer radiotherapy are poorly known. In this regard, the present study is aimed to investigate the effect of irradiated tumor cells on the bystander counterparts in mouse fibrosarcoma (WEHI 164 cells) tumor model. Mice co-implanted with WEHI 164 cells γ-irradiated with a lethal dose of 15 Gy and unirradiated (bystander) WEHI 164 cells showed inhibited tumor growth, which was measured in terms of tumor volume and Luc+WEHI 164 cells based bioluminescence in vivo imaging. Histopathological analysis and other assays revealed decreased mitotic index, increased apoptosis and senescence in these tumor tissues. In addition, poor angiogenesis was observed in these tumor tissues, which was further confirmed by fluorescence imaging of tumor vascularisation and CD31 expression by immuno-histochemistry. Interestingly, the growth inhibitory bystander effect was exerted more prominently by soluble factors obtained from the irradiated tumor cells than the cellular fraction. Cytokine profiling of the supernatants obtained from the irradiated tumor cells showed increased levels of VEGF, Rantes, PDGF, GMCSF and IL-2 and decreased levels of IL-6 and SCF. Comparative proteomic analysis of the supernatants from the irradiated tumor cells showed differential expression of total 24 protein spots (21 up- and 3 down-regulated) when compared with the supernatant from the unirradiated control cells. The proteins which showed substantially higher level in the supernatant from the irradiated cells included diphosphate kinase B, heat shock cognate, annexin A1, angiopoietin-2, actin (cytoplasmic 1/2) and stress induced phosphoprotein 1. However, the levels of proteins like annexin A2, protein S100 A4 and cofilin was found to be lower in this supernatant. In conclusion, our results provided deeper insight about the damaging RIBE in an in vivo tumor model, which may have significant implication in improvement of cancer radiotherapy.

Enhancement of the tumour inhibitory activity, in vivo, of diospyrin, a plant-derived quinonoid, through liposomal encapsulation.

Diospyrin, a bisnaphthoquinonoid plant product, shows inhibitory activity against murine tumour in vivo and human cancer cell lines in vitro. Efforts have further been made to obtain synthetic derivatives of diospyrin with the objective of improved therapeutic effects. With the goal to reduce the toxicity towards normal cells and enhance the efficacy to tumour cells, diospyrin was encapsulated in liposomal vesicle and its antitumour potential was observed on the growth of Ehrlich ascites tumour in Swiss mice. It was found that the longevity of the tumour-bearing mice was significantly enhanced by treatment with liposomal diospyrin as compared with the free drug. Biochemical assay of liver function enzymes, viz. LDH, AP, GOT and GPT in blood serum of the tumour-bearing mice showed substantial alterations in the activity of these enzymes. These parameters were, however, restored to near normal level when the drug treatment was given encapsulated in a liposome. Histopathological studies on the liver tissues indicated a near normal pathological status in the treated animals despite being challenged by tumour cells. This study on diospyrin has shown, for the first time, an enhancement of its antitumour effect in vivo through liposomal encapsulation.

Doxorubicin enhances (131)I-rituximab induced cell death in Raji cells.

AIM: There are various therapeutic modalities of treatment for non-Hodgkin's lymphoma, but with certain limitations, hence, investigating the scope of combined therapeutic approach. MATERIALS AND METHODS: In this article, cellular toxicity, apoptosis and expression of mitogen-activated protein kinase signaling pathway proteins were investigated in Raji cells preincubated with doxorubicin followed by (131)I-rituximab (rituximab radiolabeled with Iodine-131) treatment. RESULTS: It was found that the (131)I-rituximab in combination with doxorubicin showed a higher amount of cell toxicity and apoptosis compared to respective controls. Expression of anti-apoptotic protein (B-cell lymphoma-extra-large) was downregulated and cleavage of poly (ADP-ribose) polymerase, a marker of apoptosis was higher in cells treated with doxorubicin (2 µg/mL) and 131 I-rituximab (P ≤ 0.05). Moreover, in these cells the basal level of expression of p42/44 and p38 were increased while its phosphorylation was decreased. CONCLUSION: These results suggest that doxorubicin has the potential to sensitize (131)I-rituximab induced cell death in Raji cells.