Home About us Editorial board Ahead of print Current issue Search Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2014  |  Volume : 10  |  Issue : 4  |  Page : 979-984

Sanazole directed targeting of silver nanoparticle drug complex to tumor mass: A preclinical investigation in murine model


1 Department of Radiation Biology, Amala Cancer Research Centre, Thrissur, India
2 Pushpagiri Institute of Medical Sciences and Research Centre, Thiruvalla, Kerala, India

Date of Web Publication9-Jan-2015

Correspondence Address:
Cherupally Krishnan Krishnan Nair
Dean of Research, Pushpagiri Institute of Medical Sciences and Research Centre, Thiruvalla - 689 101, Kerala
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0973-1482.148705

Rights and Permissions
 > Abstract 

Aim of Study: To explore sanazole (AK) directed targeting of the antineoplastic drug doxorubicin (DOX) complexed with silver nanoparticles (SNs) to tumor growth in a murine model.
Materials and Methods: Sanazole (AK) and DOX were complexed with SNs, individually and in combination to obtain SN-AK, SN-DOX, and SN-AK-DOX. Solid tumors were developed on hind limbs of Swiss albino mice by transplanting Dalton's lymphoma ascitess (DLAs) tumor cells. Induction of cytotoxicity and apoptosis in the DLA cells by AK and DOX complexed with SN, individually and in combination, were examined under in vitro conditions by incubating the cells with them. SN, AK, DOX, SN-AK, SN-DOX, AK-DOX, and SN-AK-DOX were administered orally to the tumor bearing mice and the therapeutic efficacy of AK-directed targeting of SN-DOX complexes to achieve tumor control was monitored.
Results: Under in vitro conditions, SN, AK, DOX, SN-AK, SN-DOX, AK-DOX, and SN-AK-DOX induced cytotoxicity and apoptosis in DLA cells to varying extents. The SN-AK-DOX complex showed higher level of cytotoxicity and apoptosis-induction in DLA cells. Similarly, administration of SN, AK, DOX, SN-AK, SN-DOX, AK-DOX, and SN-AK-DOX resulted in significant reduction in tumor volume and delay in tumor growth. The animals treated with SN-AK-DOX had the highest reduction in tumor volume and tumor growth. In fact, the tumor was almost absent in the animals of this group after the treatment.
Conclusion: The SN complex of sanazole and doxorubicin together (SN-AK-DOX) has high anticancer activity under in vivo conditions and has great potential in tumor therapy.

 > Abstract in Chinese 

沙纳唑靶向引导纳米银药物复合物作用于肿瘤:小鼠模型的临床前研究

摘要

研究目的:探讨沙纳唑(AK)靶向引导抗肿瘤药物阿霉素(DOX)纳米银粒子(SNs)复合物作用于鼠科模型中肿瘤的生长。

材料与方法:将沙纳唑(AK)、阿霉素(DOX)单体及合成物分别与纳米银(SNs)合成,获得SN-AK、SN-DOX和SN-AK-DOX。实体瘤是通过在瑞士白化小鼠后肢移植达尔顿淋巴瘤腹水(DLAS)肿瘤细胞而培育。在体外条件下培育DLA细胞,分别单独加入AK、DOX及SN或它们的复合物,检查细胞毒性和诱导凋亡作用。SN、 AK、DOX、SN-AK、SN-DOX、AK-DOX及 SN-AK-DOX通过口服给药于肿瘤小鼠,对AK靶向引导的SN-DOX复合物控制肿瘤的治疗效果进行监测。

结果:在体外条件下,SN、AK、DOX、SN-AK、SN-DOX、AK-DOX 及 SN-AK-DOX诱导的细胞毒性和细胞凋亡表现出不同的程度。SN-AK-DOX复合体在DLA细胞中表现出更高的细胞毒性和细胞凋亡的诱导能力。同样,SN、AK、DOX、SN-AK、SN-DOX、AK-DOX及 SN-AK-DOX的注入明显导致肿瘤体积的减少和肿瘤生长的延迟。SN-AK-DOX治疗的动物最大地减少了肿瘤体积,延缓了肿瘤生长。事实上,这一组动物的肿瘤在治疗后几乎都消失了。

结论:阿霉素的沙纳唑纳米银复合物(SN-AK-DOX)在体内具有很高的抗癌活性,在肿瘤治疗中具有很大的潜力。

关键词:抗肿瘤活性,DLA细胞,阿霉素,靶向药物,沙纳唑,纳米银

Keywords: Anti-tumor activity, DLA cells, doxorubicin, drug targeting, sanazole, silver nanoparticles


How to cite this article:
Nair GG, Nair CK. Sanazole directed targeting of silver nanoparticle drug complex to tumor mass: A preclinical investigation in murine model . J Can Res Ther 2014;10:979-84

How to cite this URL:
Nair GG, Nair CK. Sanazole directed targeting of silver nanoparticle drug complex to tumor mass: A preclinical investigation in murine model . J Can Res Ther [serial online] 2014 [cited 2019 Oct 20];10:979-84. Available from: http://www.cancerjournal.net/text.asp?2014/10/4/979/148705


 > Introduction Top


Doxorubicin (DOX), the anthracycline antibiotic produced by the fungus Streptomyces peucetius,[1] is extensively used as an antineoplastic agent in the treatment of both hematological and solid malignancies. [2],[3] DOX damages deoxyribonucleic acid by intercalation of the anthracyline portion, metal ion chelation, or by generation of free radicals. DOX is most effective in the treatment of patients with sarcomas. However, anthracycline cardiotoxicity represents a serious risk of anticancer chemotherapy. [4]

Clinically, tumor hypoxia reduces the effectiveness of radiation therapy as well as chemotherapy. [5] In the past, approaches directed at overcoming the potential problem of tumor hypoxia have focused primarily on the development of methods aimed at improving tumor oxygenation by increasing the quantity of oxygen delivered to the tumor. [6],[7] Nitroimidazoles have been shown to be potent sensitizers of certain clinically active chemotherapeutic agents. [8] This process of chemopotentiation has been shown to be hypoxia-mediated. [9] Sanazole [AK 2123 or N-(2-methlyoxyethyl) -3-(3"- nitro-1"triazoyl) acetamide], a nitrotriazole hypoxic cell sensitizer [Figure 1] that has widely been used in combination with a number of cancer therapies such as thermotherapy, chemotherapy, and radiotherapy. [10] Sanazole (AK) induces apoptosis in murine fibrosarcoma cells and enhances the level of caspase-3 enzyme and internucleosomal fragmentation. [5] Sanazole has been found to accumulate in hypoxic cells of tumors and this property has facilitated its utility for tumor imaging. [11],[12]
Figure 1: Chemical structure of sanazole (AK)

Click here to view


The present work concerns sanzole directed targeting of silver nanoparticle (SN) complexed DOX and sanazole (SN-AK-DOX) to control growth of solid tumors on hind limbs of mice. Studies on the effect of these complexes on induction of deoxyribonucleic acid (DNA) damage and apoptosis in Dalton's lymphoma ascitess (DLA) tumor cells under in vitro conditions were also done to illustrate the mechanism underlying the antitumor potential of these complexes.


 > Materials and methods Top


Chemicals

The SNs were obtained from Dr. P K Khanna, CMET, Pune. Sanazole/AK-2123 (AK) was obtained from Prof. V. T. Kagiya, Kinki Research Foundation, Kyoto, Japan. DOX HCl procured from Dabur India Ltd., Ghaziabad, India. Dulbecco's Modified Eagle's Media (DMEM) from Gibco. Giemsa and May-Grunwald stain, poly oxy ethylene 25 propylene glycol Stearate (POES), trypan blue stain were obtained from Sigma chemicals Inc. USA. All other fine chemicals were of analytical grade purchased from reputed Indian manufacturers.

Animals

Swiss albino mice of 4-6 weeks old, weighing 20-25 g were obtained from the Small Animal Breeding Section, Veterinary University, Mannuthy, Kerala, India. They were maintained under standard conditions of temperature and humidity in the Centre's Animal House Facility. The animals were provided with standard mouse chow (Sai Durga Feeds and Foods, Bangalore, India) and water ad libitum. All animal experiments were carried out with the prior approval of the Institutional Animal Ethics Committee and were conducted strictly adhering to the guidelines of Committee for the Purpose of Control and Supervision of Experiments on Animals (149/99/CPCSEA) constituted by the Animal Welfare Division of Government of India.

Preparation of SNs and SN complexes of AK and DOX

Colloidal suspension of silver (1%) was prepared by sonicating SNs in 5% POES in sterile distilled water. SN-AK complexes were prepared by adding 1% sanazole to the above prepared SN solution under ultrasonication. SN-DOX complexes were prepared by addition of DOX to 0.1% to the SN solution under ultrasonication. SN-AK-DOX complexes were obtained by reacting sanazole (1%) and DOX (0.1%) with SN solution under ultrasonication. Graphical illustration is given as [Figure 2].
Figure 2: Graphical illustration depicting the preparation of silver nanoparticle (SN)-doxorubicin (DOX), SN-sanazole (AK), and SN-AK-DOX

Click here to view


Tumour induction

DLA cells were maintained in vivo in Swiss albino mice, by intraperitoneal transplantation. The cells were aspirated from peritoneal cavity of the DLA tumor bearing mice and 0.1 mL containing 10 6 cells was injected subcutaneously into the right hind limb of all animals for solid tumor development.

Determination of cytotoxicity of SN, AK, DOX, and their complexes in DLA cells in vitro

The cytotoxicity of SN, AK, DOX, and their complexes in DLA cells in vitro was analyzed using trypan blue dye exclusion method.[13] DLA cells (1-2 × 10 6 cells/mL) were washed with ice cold phosphate buffer saline to remove blood cells and cell debris and were incubated in DMEM supplemented with 2% serum with the nanoparticle complexes as detailed below.

The tumor cells were incubated with SN (50 μg/mL); AK (50 μg/mL); DOX (5 μg/mL); SN-AK (50 μg AK complexed with SN/mL); SN-DOX (5 μg DOX complexed with SN/mL); AK-DOX (50 μg AK and 5 μg DOX/mL); SN-AK-DOX (50 μg AK and 5 μg DOX complexed with SN/mL) for different time intervals 0, 30, and 60 min. The cell mortality was counted with the help of haemocytometer for these time intervals.

Evaluation of cellular DNA damage in tumor tissue induced by SN, AK, DOX, and their complexes

To monitor the effects of SN, AK, DOX, and their complexes on cellular DNA damage in DLA tumor cells in vitro, DLA (10 6 cells/mL) were treated with SN (50 μg/mL); AK (50 μg/mL); DOX (5 μg/mL); SN-AK (50 μg AK complexed with SN/mL); SN-DOX (5 μg DOX complexed with SN/mL); AK-DOX (50 μg AK and 5 μg DOX/mL); SN-AK-DOX (50 μg AK and 5 μg DOX complexed with SN/mL) for 4 h. The extent of DNA damage was measured at 1 st h and at 4 th h of incubation by comet assay or alkaline single cell gel electrophoresis. [14],[15],[16] After electrophoresis, the slides were dried and subjected to silver staining. [15],[16],[17] The comets were visualized using compound light microscope, images were captured and a minimum of 50 comets per slide, in triplicates for a group were analyzed using the software ''CASP'' which gives % DNA in tail, tail length, tail moment (TM), and Olive TM (OTM) directly. The parameter TM is the product of tail length and %DNA in tail and OTM is the product of the distance between the center of the head and the centre of the tail and %DNA in tail. [18],[19],[20] Results are given as mean ± standard deviation (SD).

Evaluation of apoptosis in tumor tissue induced by SN, AK, DOX, and their complexes

DLA cells (1-2 × 10 6 cells/mL), were washed with ice cold phosphate buffer saline and incubated with the nanoparticle complexes (0.01 vol) in DMEM supplemented with 2% serum for 4 h as detailed above. On 1 st and 4 th h of incubation, smears were prepared on clean grease free glass slides and were fixed with methanol for 1 min. These were stained with diluted May-Grunwald stain for 10 min, rinsed with distilled water, and stained with diluted Giemsa for 30 min. [21] Washed and kept in phosphate buffer for 15-20 min. The slides were allowed to dry and mounted with DPX. Apoptotic cells characterized by cytoplasmic blebbing and nuclear fragmentation were visualized using bright field microscope and apoptotic index was calculated. [5]

To analyze internucleosomal fragmentation, DNA was isolated after 4 h of incubation with the drugs and complexes, using the procedure of Kuo et al., [22] and agarose gel electrophoresis was performed on the isolated DNA at 55 V for 3 h, stained with ethidium bromide and photographed.

Effect of SN, AK, DOX, and their complexes on tumor reduction in DLA solid tumor bearing animals

Solid tumor was developed by injecting DLA cells (1 × 10 6 cells/animal) subcutaneously in to the right hind legs of Swiss albino mice. These tumor transplanted mice were divided into groups of 10 each and the animals were administered with either SN, AK, DOX, or their SN-complexes on the 7 th day of tumor transplantation, when the tumor has grown to a size of 1 cc.

Group I − 0.1 mL distilled water

Group II − SN (0.1 mL of 1% soln.)

Group III − AK (0.1 mL of 1% soln.)

Group IV − DOX (0.1 mL of 0.1% soln.)

Group V − SN-AK (0.1 mL contains 1% SN and 1% AK)

Group VI − SN-DOX (0.1 mL contains 1% SN and 0.1% DOX)

Group VII − AK-DOX (0.1 mL contains 1% AK and 0.1% DOX)

Group VIII − SN-AK-DOX (0.1 mL contains 1% SN, 1% AK, and 0.1% DOX)

The administration of SN, AK, DOX, SN-AK, SN-DOX, AK-DOX, or SN-AK-DOX was continued for next 5 days. The hind leg thicknesses were measured using a vernier calliper once in three days from 7 th day of tumor transplantation. The tumor volume was calculated as follows:

Tumour volume = 4/3 ð r 1 2 × r 2 (were, r 1 is the minor radius and r2 is the major radius)

Statistical analysis

The data are expressed as mean ± SD. The significance levels for comparison of differences were analyzed using analysis of variance with Tukey-Kramer multiple comparisons test. The treated groups were compared with the respective control groups. The differences between means were considered statistically significant at P < 0.05.


 > Results Top


Determination of cytotoxicity of SN, AK, DOX, and their complexes in DLA cells in vitro

The results on cytotoxicity induced by SN, AK, DOX, and the nanoparticle complexes in DLA cells are presented in [Figure 3]. All the drugs including SN were cytotoxic to the tumor cells. The nanoparticle complexes of the drugs and AK-DOX have shown higher toxicity than the drugs or nanoparticle alone treated groups. SN-AK-DOX complex exerted the highest cytotoxicity as compared with all the other treatments. The SN-AK-DOX complex caused 99.45% killing of DLA cells in an hour.
Figure 3: Cytotoxic effect of silver nanoparticle, sanazole, doxorubicin and their complexes on Dalton's lymphoma ascites tumor cells. Values are presented as mean ± standard deviation

Click here to view


Evaluation of cellular DNA damage in tumor tissue induced by SN, AK, DOX, and their complexes

Treatments with SN, AK, DOX, and their complexes induced severe damage to the cellular DNA in DLA tumor cells and resulted in an increase in the comet parameters such as %DNA in tail, tail length, TM, and OTM, indicate DNA strand breaks. The extent of DNA damage in tumor cells treated with SN-AK-DOX was much higher than that of other treatments, evidenced from the results obtained during the 1 st h of treatments. There was also an elevated increase in all the parameters by 4 th h after treatments. The results are illustrated in [Figure 4]a. The morphology of cell DNA showing comets is showed in [Figure 4]b, the fan-like appearance of comets denotes the induction of apoptosis by SN, AK, DOX, and their complexes. The result, thus, indicates enhanced potential of SN-AK-DOX to induce genotoxicity in tumor cells.
Figure 4: (a) Effect of silver nanoparticle, sanazole, doxorubicin, and their complexes on induction of deoxyribonucleic acid (DNA) strand breaks in Dalton's lymphoma ascitess cells, analysed by comet assay. The parameters like percentage DNA in tail (i), tail length (ii), tail moment (iii), and Olive tail moment (iv) are presented as mean ± standard deviation, (b) Effect of silver nanoparticle (SN), sanazole (AK), doxorubicin (DOX), and their complexes on induction of deoxyribonucleic acid (DNA) damage in Dalton's lymphoma ascitess tumor cells, and fan-like comets indicate the DNA damage by apoptosis. No Drug- i; SN- ii; AK- iii; DOX- iv; SN-AK- v; SN-DOX- vi; AK-DOX- vii; and SN-AK-DOX- viii

Click here to view


Evaluation of apoptosis in tumor tissue induced by SN, AK, DOX, and their complexes

Apoptotic induction on DLA tumor cells by SN, AK, DOX, and their complexes in vitro was studied by analyzing the morphological pattern of the cells and the apoptotic index at 1 st and 4 th hour of treatments was scored and calculated, illustrated in [Table 1].
Table 1: Effect of silver nanoparticle, sanazole, doxorubicin, and their complexes on induction of apoptosis in Dalton's lymphoma ascites cells

Click here to view


The results showed higher apoptotic index in cells treated with SN-AK-DOX at both the intervals, when compared with other complexes and drugs alone treated groups. The apoptosis and DNA damage in the tumor cells was also confirmed with the internucleosomal fragmentation assay at the 4 th hour, as revealed from [Figure 5]. It can be seen in the figure that the DNA isolated from the tumor cells treated with the nanoparticle, drugs and their complexes showed laddering on gel electrophoresis.
Figure 5: Effect of silver nanoparticle (SN), sanazole (AK), doxorubicin (DOX), and their complexes on induction of apoptosis in Dalton's lymphoma ascites tumor cells, and deoxyribonucleic acid showing ladder pattern on gel electrophoresis assay. Lane 1- No Drug; Lane 2- SN; Lane 3- AK; Lane 4- DOX; Lane 5- SN-AK; Lane 6- SN-DOX; Lane 7- AK-DOX; and Lane 8- SN-AK-DOX

Click here to view


Effect of SN, AK, DOX, and their complexes on tumor reduction in DLA solid tumor bearing animals

The oral administration of SN, AK, DOX, and the SN-complexes delayed the tumor growth in DLA solid tumor bearing mice, results as depicted in [Figure 6]a and [Figure 6]b. [Figure 6]b is a representative photograph of the animals and their tumor bearing limbs before and after treatments on 25 th day. The growth of the tumor was found to be significantly suppressed in animals administered with SN-DOX or SN-AK-DOX compared with untreated control animals and SN, AK, DOX, SN-AK, or AK-DOX treated groups. The reduction in tumor growth was more prominent in the groups of animals administered with SN-AK-DOX.
Figure 6: (a) Effect of oral administration of silver nanoparticle, sanazole, doxorubicin, and their complexes on tumor growth delay in Dalton's lymphoma ascites solid tumor bearing mice, (b) Effect of oral administration of silver nanoparticle, sanazole, doxorubicin, and their complexes on reduction of tumor growth in Dalton's lymphoma ascites solid tumor bearing mice

Click here to view



 > Discussion Top


DOX a widely used anticancer drug. [2],[3] The quinone structure of DOX enhances the catalysis of oxidation-reduction reactions, thereby promoting the generation of oxygen free radicals, which may be involved in antitumor effects as well as toxicity associated with this drug. [23] The complex of SN-AK-DOX enhanced the cytotoxic property as compared with that of AK and DOX as revealed by the increase in the in vitro cytotoxicity toward DLA cells. The complexing of the two drugs with SN could have resulted in a synergistic cytotoxic effect which may be due to the chemosensitizing action exerted on DOX by sanazole, which resulted in enhanced cytotoxicity of the complex. The comet assay on the tumor cells treated with the drugs and their complexes revealed the potent action of SN-DOX and SN-AK-DOX in inducing DNA damage in tumor. The mechanism of action is supposed to be the induction of apoptosis as the treatment of DLA cells with nanoparticle, drugs, and their complexes showed apoptotic morphology and DNA laddering. SN-AK-DOX complex induced apoptosis in tumor cells more efficiently than the individual components-SNs, AK, and DOX. The in vivo experiment, with tumor bearing Swiss albino mice, also showed promising results of anticancer activity of SNs complexed with AK and DOX together.

Nanoparticles exhibit novel electronic/optical properties, synthetic tenability over a wide range, and can be conjugated to an array of biologically-active molecules for tailored diagnostic/therapeutic applications, and nanoparticles can present thousands of binding sites for the drugs. Poorly soluble molecules or those which normally enter the cell through passive diffusion can be rapidly delivered across the cell membrane by receptor-mediated nanoparticle endocytosis, delivering thousands of additional molecules into the targeted cell. [24] The pharmacokinetics and pharmacodynamics of nanoparticles can be tailored by the size, shape, and composition of the nanoparticle and may serve useful for drug delivery of chemotherapeutic agents. Nanoparticles can be used as tools for targeted delivery of antineoplastic agents and enzymes for oxidation therapy, to tumor mass. [25],[26],[27],[28] The hypoxic cell sensitizer AK has the property of accumulating in tumors and this has been shown to be useful in imaging hypoxic tumors. [11],[12] AK in the complex SN-AK-DOX results in the accumulation of the complexes in the cells of the tumor and this would cause annihilation of the tumor in the animals.


 > Acknowledgment Top


The authors thank Dr. P K Khanna, CMET, Pune, for providing SNs and Prof. V.T. Kagiya, Kinki Research Foundation, Kyoto, Japan for giving sanazole (AK).

 
 > References Top

1.
Arcamone F, Cassinelli G, Fantini G, Grein A, Orezzi P, Pol C, et al. Adriamycin, 14-hydroxydaimomycin, a new antitumor antibiotic from S. Peucetius var. caesius. Biotechnol Bioeng 1969;11:1101-10.  Back to cited text no. 1
    
2.
Yee GC. Oncologic disorders. In: Dipiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey MI, editors. Pharmacotherapy: A Pathophysiologic Approach. 6 th ed. New York: McGraw-Hill; 2005. p. 2279-232 8.  Back to cited text no. 2
    
3.
Chabner BA, Amrein PC, Druker BJ, Michaelson MD, Mitsiades CS, Gross PE, et al. In: Brunton LL, Laso JS, Parker KL, editors. Goodman and Gilman′s The Pharmacological Basis of Therapeutics. 11 th ed. New York: McGraw-Hill; 2006. p. 1315-1 404.  Back to cited text no. 3
    
4.
Sterba M, Simunek T, Popelova O, Potacova A, Adamcova M, Mazurova Y, et al. Early detection of anthracycline cardiotoxicity in a rabbit model: Left ventricle filling pattern versus troponin T determination. Physiol Res 2007;56:535-45.  Back to cited text no. 4
    
5.
Rajagopalan R, Kagiya VT, Nair CK. Radiosensitizer sanazole (AK2123) enhances up radiation-induced apoptosis in murine fibrosarcoma. J Radiat Res 2003;44:359-65.  Back to cited text no. 5
    
6.
Hirst DG. Tissue oxygenation and hypoxia in tumors. In: Fielden EM, Fowler JF, Hendry JH, Scott D, editors. Proceedings of the 8 th International Congress of Radiation Research. London: Taylor and Francis; 1988. p. 695.  Back to cited text no. 6
    
7.
Siemann DW. New trends in improving oxygen delivery to tumor tissues. In: Fielden EM, Fowler JF, Hendry JH, Scott D, editors. Proceedings of the 8 th International Congress of Radiation Research. London: Taylor and Francis; 1988. p. 713.  Back to cited text no. 7
    
8.
Huilgol NG, Nair CK, Kagiya VT. Radiosensitizers in clinical practice, a contemporary audit. New Delhi: Narosa Publishers; 2000.  Back to cited text no. 8
    
9.
Siemann DW, Allalunis-Turner MJ. Potentiation of combination chemotherapy by nitroheterocyclics. Int J Radiat Oncol Biol Phys 1988;15:129-34.  Back to cited text no. 9
    
10.
Alam A, Rapthap CC, Singha LI, Sharan RN, Singh V. Radiomodulatory effect of liposome encapsulated AK-2123 on tumor in mice exposed to hepatocarcinogen. Mol Cell Biochem 2005;271:139-50.  Back to cited text no. 10
    
11.
Murugesan S, Shetty SJ, Noronha OP, Samuel AM, Srivastava TS, Nair CK, et al. Technetium-99m-cyclam AK-2123: A novel marker for tumor hypoxia. Appl Radiat Isot 2001;54:81-8.  Back to cited text no. 11
    
12.
Das T, Chakraborty S, Banerjee S, Mukherjee A, Samuel G, Sarma HD, et al. Preparation and preliminary evaluation of a 177 Lu labeled sanazole derivative for possible use in targeting tumor hypoxia. Bioorg Med Chem 2004;12:6077-84.  Back to cited text no. 12
    
13.
Talwar GP. Hand Book of Practical Immunology. New Delhi: National Book Trust; 1974. p. 336-33 9.  Back to cited text no. 13
    
14.
Singh NP. Microgels for estimation of DNA strand breaks, DNA protein cross links and apoptosis. Mutat Res 2000;455:111-27.  Back to cited text no. 14
    
15.
Nair GG, Nair CK. Protection of cellular DNA and membrane from γ-radiation induced damages and enhancement in DNA repair by sesamol. Cancer Biother Radiopharm 2010;25:629-35.  Back to cited text no. 15
    
16.
Nair GG, Nair CK. Amelioration of γ-radiation induced genomic insult and oxidative stress in whole body irradiated Swiss albino mice by sesamol. Int J Low Radiat 2011;8:20-34.  Back to cited text no. 16
    
17.
Chandrasekharan DK, Kagiya VT, Nair CK. Radiation protection by 6-palmitoyl ascorbic acid-2-glucoside: Studies on DNA damage in vitro, ex vivo, in vivo and oxidative stress in vivo. J Radiat Res 2009;50:203-12.  Back to cited text no. 17
    
18.
Cerda H, Delincée H, Haine H, Rupp H. The DNA ′comet assay′ as a rapid screening technique to control irradiated food. Mutat Res 1997;375:167-81.  Back to cited text no. 18
    
19.
Konca K, Lankoff A, Banasik A, Lisowska H, Kuszewski T, Gozdz S, et al. A cross-platform public domain PC image-analysis program for the comet assay. Mutat Res 2003;534:15-20.  Back to cited text no. 19
    
20.
Sandeep D, Nair CK. Protection of DNA and membrane from γ-radiation induced damage by the extract of Acorus calamus Linn: An in vitro study. Environ Toxicol Pharmacol 2010;29:302-7.  Back to cited text no. 20
    
21.
Chaubey RC, Bhilwade HN, Joshi BN, Chauhan PS. Studies on the migration of micronucleated erythrocytes from bone marrow to the peripheral blood in irradiated Swiss mice. Int J Radiat Biol 1993;63:239-45.  Back to cited text no. 21
    
22.
Kuo CL, Chou CC, Yung BY. Berberine complexes with DNA in the berberine induced apoptosis in human leukemic HL-60 cells. Cancer Lett 1995;93:193-200.  Back to cited text no. 22
    
23.
Doroshow JH, Davies KJ. Redox cycling of anthracyclines by cardiac mitochondria. II. Formation of superoxide anion, hydrogen peroxide, and hydroxyl radical. J Biol Chem 1986;261:3068-74.  Back to cited text no. 23
    
24.
Dreaden EC, Mwakwari SC, Sodji QH, Oyelere AK, El-Sayed MA. Tamoxifen-poly (ethylene glycol)-thiol gold nanoparticle conjugates: Enhanced potency and selective delivery for breast cancer treatment. Bioconjug Chem 2009;20:2247-53.  Back to cited text no. 24
    
25.
Jayakumar OD, Ganguly R, Tyagi AK, Chandrasekharan DK, Nair CK. Water dispersible Fe 3 O 4 nanoparticles carrying doxorubicin for cancer therapy. J Nanosci Nanotechnol 2009;9:6344-8.  Back to cited text no. 25
    
26.
Divakaran SA, Sreekanth KM, Rao KV, Nair CK. D-aminoacid oxidase-Fe 2 O 3 nanoparticle complex mediated antitumor activity in Swiss albino mice. J Cancer Ther 2011;2:666-74.  Back to cited text no. 26
    
27.
Ramachandran L, Nair CK. Therapeutic potentials of silver nanoparticle complex of α-lipoic acid. Nanomater Nanotechnol 2011;1:17-24.  Back to cited text no. 27
    
28.
Chandrasekharan DK, Nair CK. Studies on silver nanoparticle- glycyrrhizic acid complex as a radioprotector and an adjuant in radiotherapy under in vivo conditions. Cancer Biother Radiopharm 2012;27:642-51.  Back to cited text no. 28
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
 
 
    Tables

  [Table 1]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

  >Abstract>Introduction>Materials and me...>Results>Discussion>Acknowledgment>Article Figures>Article Tables
  In this article
>References

 Article Access Statistics
    Viewed1573    
    Printed39    
    Emailed0    
    PDF Downloaded123    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]