الفهرس 
INTRODUCTION AND AIM OF THE WORKOnly 14 pages are availabe for public view
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Abstract
Cancer is a significant public health problem, with substantial death and disability. It is the second leading cause of death worldwide and among three leading causes of death in developing countries for adults. One out of every two men and one out of every three women will have a certain form of cancer during their lifetime at some point. Cancer is a group of more than 100 diseases that develop across time and involve the uncontrolled division of the body’s cells and begins to follow its own agenda for proliferation. Although cancer can develop in virtually any of the body’s tissues, and each type of cancer has its unique features, the basic processes that produce cancer are quite similar in all forms of the disease. Cancer cells can also instruct surrounding tissues to undergo changes that promote malignancy. Understanding the complex ways in which cancer cells interact with their surroundings, both locally in the tumor organ and systemically in the body as a whole, has implications for effective cancer prevention and therapy. Anti-tumour therapy resistance is a major obstacle in cancer chemotherapy and accounts for the chemotherapy failure. Therefore, there is a consistent need to establish new, efficient and affordable anti-tumour therapies. Due to the toxic effects and absence of selectivity of most chemotherapeutic candidates, natural therapeutics is selected for their acceptability and toxicity reduction. Consequently, the literature on the potential and medicinal properties of herbal drugs such as thymoquinone (TQ) to augment therapeutic effects of anticancer drugs protecting normal tissues against chemotherapy-induced damages has been a growing. Thymoquinone (TQ) is the bioactive constituent of the volatile oil of black seed and exerts anti-inflammatory, anti-oxidant and anti-neoplastic effects both in vitro and in vivo. Recent studies have reported that TQ can improve the toxicity of an anti-cancer drug (cyclophosphamide) by its anti-toxic effects and anti-viral Chapter 6 Summary and Conclusion 19 6 effects. TQ has also been shown to potentiate the anti-tumor activity of anti-cancer drugs such as cisplatin and 5-fluorouracil and the induced nephrotoxicity. It has reported also that it enhances the activity of T cells and reduces their apoptosis. It has been shown significant in vitro and in vivo anti-tumor effects against several preclinical cancer cell models. Most importantly, the anti-tumor effects and the potential toxicity of TQ were evaluated in phase I study in patients with advanced cancer for which there were no standard curative or palliative measures. TQ has poor solubility, so its combination alone or loaded onto nanoparticles with chemotherapy would improve its uptake by the cancer cells. Consequently, the present study aimed to evaluate in vitro and in vivo anti-cancer effectiveness of TQ–conjugated AuNPs or AgNPs (AuNPs/TQ or AgNPs/TQ composites) in presence or absence of systemic chemotherapeutic drug cisplatin. Also, to investigate the ameliorative effect of this regimen on liver tissue alternations prompted by cancer chemotherapy in tumour-bearing mice. I. In vitro study: Antitumor activity of (AuNPs/TQ) and (AgNPs/TQ): Ehrlich ascites carcinoma (EAC) cell line were subjected to different concentrations of the synthesized AuNPs, AgNPs-loaded with or without TQ in order to investigate: their anti-tumor activities and their proliferation inhibition against tumor cells and their half maximal inhibition concentration (IC50) using MTT assay to use in the in vivo experimentation. The in vitro results indicated that: The synthesized AuNPs, AgNPs-loaded with or without TQ (TQ, AuNPs, AuNPs/TQ, AgNPs and AgNPs/TQ composite) specifically affect the EAC tumor cells proliferation and the in vitro IC50 values had been estimated at 338.96 μg/ml for TQ , 30.88 μg/ml for AuNPs, 32.798 μg/ml for AuNPs/TQ, 63.29 μg/ml for Chapter 6 Summary and Conclusion 19 7 AgNPs and 62.02 for AgNPs/TQ respectively. The In vivo LD50 values of tested compounds had been estimated at 922 mg/kg for TQ, 378 mg/kg for AuNPs, 387 mg/kg for AuNPs/TQ, 494 mg/kg for AgNPs and 490 mg/kg for AgNPs/TQ, respectively. The experimental doses of tested compounds has been chosen at dose (1/50 in vivo LD50; 0.2 and 0.2 mg/mouse for AuNPs, AuNPs/TQ, (1/60 in vivo LD50) 0.2 and 0.2 for AgNPs and AgNPs/TQ and 0.5 mg/mouse for TQ (1/20 in vivo LD50) respectively. II. In vivo study: 1) Antitumor activity effect of TQ with or without Cis in EAC-bearing mice: Mice were IP injected with 0.5×106 EAC cells/mouse then treated with TQ in presence or absence of Cis40 resulted in a ability of TQ with or without Cis to suppress the growth of EAC cells in EAC-bearing mice. Also, untreated EAC-bearing mice showing marked disorganization of hepatic architecture, hepatocytes with degenerated and vacuolated cytoplasm, congestion of central veins, obliteration of narrowing blood sinusoids and increase in the number of Kupffer cells. The TQ treatment showed a mild improvement of the hepatic tissue, many hepatocytes with normally stained cytoplasm and nuclei. However, Cis40 treatment displayed many histopathological changes comprise noticeable disorganization of hepatic architecture, hepatocytes with vacuolated cytoplasm, many hepatocytes show pyknotic nuclei, others with karyolitic ones, cellular infiltration and hepatocytes in the portal area exhibit highly hypereosinophilia. Nevertheless, the combination of TQ and Cis40 displayed mild improvement of tissues, many hepatocytes with normally stained Chapter 6 Summary and Conclusion 19 8 cytoplasm and nuclei, but some hepatocytes with pyknotic nuclei and karyolitic nuclei. 2) Antitumor activity and cellularity effect of TQ (0.5 mg)-loaded AuNPs or AgNPs with or without Cis. Mice were IP injected with 0.5×106 EAC cells/mouse then they divided randomly into 10 groups. One day later, EAC-bearing mice orally treated daily with AuNPs or AgNPs with or without TQ(0.5 mg) in presence or absence of Cis for 6 successive days: Mice were sacrificed by cervical dislocation on day 11 post EAC inoculation tumor growth, hematological analysis, biochemical assays, immunological investigations and histopathological examination of liver were carried out. The results showed that combining the anti-tumor effect of TQ (0.5 mg) with or without the effective penetration properties of AuNPs or AgNPs resulted in a potent ability to suppress the growth of EAC cells in EAC-bearing mice with low cytotoxicity on healthy cells such splenocytes. Addition of chemotherapeutic agent Cis to AuNPs/TQ(0.5 mg) or AgNPs/TQ(0.5 mg) composites improved anti-proliferative and cytotoxic effects against EAC cells in EAC-bearing mice. Treatment with AuNPs/TQ(0.5 mg), AuNPs/TQ(0.5 mg)+Cis10 or AuNPs/TQ(0.5 mg)+Cis40 resulted in increased spleen CD4+T-cell population and reduced spleen CD8-T-cell expression compared to EAC-bearing expression. Also, AuNPs, AuNPs/TQ(0.5 mg)+Cis10, AgNPs, AgNPs/TQ(0.5 mg) or AgNPs/TQ(0.5 mg)+Cis(10) treatment increased the expressions of CD25+T–cell subset population while AuNPs/TQ(0.5 mg) or AuNPs/TQ(0.5 mg)+Cis40 treatment decreased the their populations. Dosage of AuNPs/TQ(0.5 mg) increased the percentage of granulocytic (CD11b+Ly6G+ cells) or monocytic (CD11b+Ly6G- cells) subtypes of myeloid cells in spleen Chapter 6 Summary and Conclusion 19 9 while AuNPs/TQ(0.5 mg)+Cis40 treatment decreased their percentage and the percentage of (CD11b-Ly6G+ cells) cell populations in spleen. Additionally, AgNPs/TQ(0.5 mg) or AgNPs/TQ(0.5 mg)+Cis10 treatment increased the percentage of monocytic (CD11b+Ly6G- cells) subtypes of myeloid cells in blood while decreased percentage of CD11b˗Ly6G+ cell populations in blood. But, AgNPs/TQ(0.5 mg) decreased the percentage of granulocytic (CD11b+Ly6G+ cells) subtypes of myeloid cells in blood whereas AgNPs/TQ(0.5 mg)+Cis(10) treatment increased their percentage. Further, administration of free AuNPs, AuNPs/TQ (0.5 mg) and AuNPs/TQ(0.5 mg)+Cis10 showing disorganization of hepatic architecture, degeneration of hepatocytes, diffuse fatty degeneration , some hepatocytes with pyknotic nuclei, dilation and congestion of blood vessels, cellular infiltration, hyperplasia and proliferation of bile ductules, blood sinusoids with activated Kupffer cells. Furthermore, the treatment with AuNPs/TQ (0.5 mg)+Cis40 viewing normal like structure, some hepatocytes with vacuolated cytoplasm, others with pyknotic nuclei, narrowed blood sinusoids with activated Kupffer cells, hyperplasia and proliferation of bile ductules, enlarged portal area with slight aggregation of monocellular infiltration. Liver sections of EAC-bearing mice treated with AgNPs/TQ(0.5mg) and AgNPs/TQ(0.5mg)+Cis10 exhibiting disorganized hepatic architecture, markedly vacuolated and degenerated cytoplasm, pyknotic nuclei, enlarged blood vessel, obliteration of narrowing blood sinusoids, thick portal area with dilated portal vein and hyperplasia of bile ductules and cellular infiltration. Chapter 6 Summary and Conclusion 20 0 3. Antitumor activity and cellularity effect of TQ (1 mg)-loaded AuNPS or AgNPs with or without Cis. Mice were IP injected with 0.5×106 EAC cells/mouse then they divided randomly into 10 groups. One day later, EAC-bearing mice orally treated daily with AuNPs or AgNPs with or without TQ(1 mg) in presence or absence of Cis for 6 successive days. Mice were sacrificed by cervical dislocation on day 11 post EAC inoculation tumor growth, hematological analysis; biochemical assays, immunological investigations and histopathological examination of liver were carried out. Data presented here further demonstrated that combination of the anti-tumor effect of TQ (1 mg) with or without the effective penetration properties of AuNPs or AgNPs occasioned a potent ability to suppress the growth of EAC cells in EAC-bearing mice with low cytotoxicity on healthy cells such splenocytes. Interestingly, addition of Cis to AuNPs/TQ or AgNPs/TQ composites significantly augmented anti-proliferative and cytotoxic effects against EAC cells in EAC-bearing mice. Additionally administration of AuNPs/TQ or AgNPs/TQ with Cis40 increased percentage of necrosis and apoptosis of EAC cells. Additionally administration of AuNPs/TQ or AgNPs/TQ with Cis40 increased percentage of necrosis and apoptosis of EAC cells.