الفهرس 
A global health problem
Breast cancerOnly 14 pages are availabe for public view
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Abstract
Many international efforts were done for preparing the most
powerful anticancer compounds which possess a lethal effect against the tumors and the least
side effects for human body aiming to reduce the percentage of deaths in cancer patients.
The present work was designed to synthesize a new gallium derivative, betaine tetrachlorogallate
(BTG), and examining its molecular and three dimensional structures. The ultimate goal is to study
its antitumor effect both on human breast cancer cell line (MCF-7) and DMBA-induced mammary tumor
in an animal model. Furthermore, this study aimed to validate whether the combination of BTG with
zinc oxide nanogard could enhance the therapeutic efficacy of the tested compound or not.
I- Synthesis of betaine tetrachlorogallate (BTG) complex:
The BTG complex was prepared by refluxing equimolar ratio of gallium trichloride anhydrous beads
(metal) and betaine hydrochloride (ligand) in ice-cold conc. hydrochloric acid (HCL). Crystals were
deposited under the surface of HCL then these were filtered using a filter paper. The
chemical structure of the prepared complex was evident by using x-ray diffraction
crystallography.
II- Biochemical studies:
a- In vitro study:
Different concentrations of BTG solution, BTG+ZnO-NPs (1
BTG : 0.25 ZnO-NPs), and ZnO-NPs suspension were prepared.
The value was detected for each, using SRB assay, against
MCF-7 human breast cell line. The values were 35.8, 70 and
110 µg/ml respectively.
b- In vivo studies:
A narrow scale experiment was performed to determine the of BTG (4170 mg/kg b.wt.)
which was considered approximately half its lethal dose.
For the in vivo application, a mammary tumor animal model was induced using
dimethylbenz(a)antheracene (DMBA) as a potent carcinogen. Eighty female albino rats were allocated
into eight groups, 10 rats /group, as following:
Group 1 (Normal control): This group comprised normal untreated female rats.
Group 2 (BTG): Rats were orally injected with daily dose of BTG (347.5±15 mg/kg b.wt.) during the
treatment fifth month, then they were sacrificed.
Group 3 (BTG+ZnO-NPs): Rats were orally injected with daily BTG (347.5±15 mg/kg b.wt.) combined
with ZnO-NPs (77.25±5 mg/kg b.wt.) day other day during the treatment fifth month, then they were
sacrificed.
Group 4 (ZnO-NPs): Rats were orally injected with ZnO-NPs suspension (77.25±5 mg/kg b.wt.) day
other day during the treatment period, then they were sacrificed.
Group 5 (DMBA): Rats received a single oral dose of 110 mg/kg b.wt. of DMBA diluted in sesame oil
given intragastrically by gavage. Then they were left for 5 months for tumor induction (no another
treatment was given at the last treatment month).
Group 6 (DMBA+BTG): After the induction period, rats
received BTG for treatment, as described in group 2.
Group 7 (DMBA+BTG+ZnO-NPs): After the induction period, rats received BTG together with ZnO-NPs
suspension for treatment, as described in group 3.
Group 8 (DMBA+ZnO-NPs): After the induction period, rats received ZnO-NPs suspension for
treatment, as described in group 4.
At the end of the treatment period, rats were sacrificed, blood and mammary gland tissue samples
were collected for the investigation of a panel of biochemical assays including; determination of
whole blood reduced glutathione (GSH) content, glutathione peroxidase (GPx), superoxide dismutase
(SOD) and catalase (CAT) enzyme activities. Lipid peroxidation (LPx) level, total iron
concentration, total iron binding capacity (TIBC) as well as liver and kidney functions; were all
estimated in plasma. Capase-3 activity was assayed in 20% mammary gland tissue homogenates.
Moreover, apoptosis study together with histopathological survey were undertaken upon mammary gland
sections of the studied groups.
Results obtained from the current study revealed that challenging female rats with DMBA was capable
of inducing oxidative stress, via ROS generation, which was manifested by elevated LPx level
accompanied by depleted antioxidant capacity (including; GSH content, GPx, SOD and CAT enzyme
activities). A non-significant elevation of caspase-3 activity in this group may indicate that the
proliferation rate, however, exceeds the apoptosis rate in the induced tumors. A significant
elevation of TIBC in this group indicates the ability of the tumors to uptake
Summary
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much more iron as a favorable atmosphere for their enhanced proliferation. Furthermore, marked elevations in ALT and AST enzymes together with mild increase in creatinine concentration, displayed by this group, could be illustrated by the effect of oxidative stress on the integrity of membranes causing damage to some organs’ tissues like liver and kidney.
Apoptosis study indicated predominant vital green-stained cells with many colonies of necrotic cells in the inner tumors which may be due to hypoxia. Histopathological study showed marked fluctuations in the architecture of the glands graded from dysplasia-to-anaplasia in the lining epithelium of the acini, which appreciate the biochemical analyses.
Administration of betaine tetrachlorogallate (BTG) alone and/or combined with zinc oxide nanoparticles (ZnO-NPs) gave rise to some sort of enhancement of the biochemical investigated parameters. This was showed by; improving some of antioxidant enzyme activities in blood (as a spontaneous body defense and/or through coping with the pro-oxidant activity of some components of the tested compounds), depletion of lipid peroxidation marker (MDA), slight amelioration of some liver and/or kidney function indicators, competition with iron in plasma as well as initiating apoptosis process, which was coupled with an increase in active caspase-3 level in the mammary gland tissues during cancer formation. Besides, ameliorating a percentage of mammary gland architecture alterations to some extent.
As a conclusion, from the current results it was found that, both BTG alone and/or combined with ZnO-NPs exerted cytotoxic effects against DMBA-induced mammary dysplasia-to- neoplasia.Summary
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These findings could, in turn, speculate a possible therapeutic role of the novel BTG compound against mammary tumors. Else more, it is worth mentioning that, the effect of the applied combined supplementation of BTG with ZnO-NPs hasn’t significantly enhanced the effect shown by the unique gallium chloride derivative (BTG) alone.
Future directions and recommendations:
The present study provides the rationale for the use of BTG alone in further preclinical testing models for breast cancer therapy, especially in early stages of the disease, or together with a suitable certain supplement with antioxidant property, as a back up to fulfill body demands for antioxidant defense system; in order to cope with the pro-oxidant activity of the gallium component of BTG complex (without interference with the antitumor action of BTG).