۱۳۸۹ آذر ۲۹, دوشنبه

بسمه تعالی
موضوع: Membrane change in cancer
استاد مربوطه:دکتر احمدی
تهیه وتنظیم :ستاره ونعمتی
Membrane change in cancer

Author: Sara Starhe, Soghra Nemati Address: Islamic Azad University, Hamadan Branch Department of Biology
Several of the plasma membrane proteins, which identified and characterized, we seem to be involved in metastasize behavior of human breast cancer.
1-This study indicates the feasibility of using mass spectrometry and other proteomics techniques find new connections between the ability of cancer cells to establish metastasis in distant organs and altered expression levels of specific proteins. Breast cancer is the most common malignant disease among in western countries.
2- The relationship between erythrocyte membrane fatty acids and postmenopausal breast cancer risk was analyzed previously only by retrospective studies.
1-Comparative quantities proteomics using stable isotope labeling with amino acids in cell culture and allows study of proteins with quantitatively different e
2- Mechanism of second study a total of 4052 postmenopausal women was followed for an average of 5.5 years; 71 cases of invasive breast cancer were identified. Our study analyzes the association between breast cancer risk and the prediagnostic fatty acid composition of erythrocyte membranes in terms of individual fatty acids and fatty acid classes. The study was conducted on the ORDET cohort of women described below, consisting of volunteers recruited to assess the association between hormone levels, diet, and the development of breast cancer.
Xpression levels on metastasizing versus non-metastasizing cells.
Ecto-5'- NT , which is a glycosylphosphatidylinositol-anchored component of lipid rafts and an enzyme converting 5'-AMP to extracellular adenosine.
The role of ecto-5'NT in cancer has been shown to adenosine generation; adenosine, acting through specific receptors, is an important metabolite released by cancer cells that establishes physiological conditions conducive to tumor progression .the relationship of ecto-5'-NTexpression ,its activity ,and adenosine generation to tumor cell biology has not been fully elucidated.
CD44 proteins are a family of ubiquitously expressed transmembrane glycoproteins and a major receptor for hyaluronan .all is forms of the protein are encoded by a single gene but are derived by alternative splicing (v1-v10) and variation in O-and N-glycosylations CD44s, the smallest and most widely expressed isoform, expressed in ducal epithelial cell and myoepithelial cell in all cases of normal and benign breast tissue; however, the expression of CD44s progressively decreases with increasing deviation from normal histology corresponding to our data.this suggests that further studies might identify different isoforms that are associated with metastatic behavior but were not elucidated the antibodies that we used.
Abstract 2:
Erythrocyte membranes characterized by higher levels of MUFAs (especially oleic acid) and a lower SI than those who did not develop breast cancer. Case women were also characterized by lower levels of the n-6 PUFA 20: 2, n-6c and n-3 docosahexaenoic acid than women who remained disease free.
These differences in membrane composition are unlikely to be a preclinical effect of the cancer because the ORDET study is a prospective study and because all participants underwent mammography or clinical examination of the breast at recruitment. Tumors not picked up by these examinations would have been of such small size that they are highly unlikely to have caused detectable changes to extratumoral tissues. However, to take account of any potential preclinical effects of breast cancer, we performed a separate analysis in which the 10 breast cancer case subjects diagnosed within 6 months of blood sampling were excluded; the results did not differ from those obtained with the use of all of the case subjects.
Linoleic acid (18: 2, n-6c).
We found a small inverse association between erythrocyte membrane linoleic acid levels and the risk of breast cancer. After absorption, the essential fatty acid linoleic acid undergoes desaturation/saturation and chain elongation/shortening reactions, producing other n-6 fatty acids. A correlation study between diet and erythrocyte membrane content (Fuhrman B: unpublished data) suggest that our finding of reduced breast cancer risk in women with high levels of linoleic acid could be partially due to protection by a diet high in this fatty acid residue and partially due to its possibly low transformation rate into other n-6 PUFAs
A new study has reported that oleic acid, the predominant fatty acid in olive oil, promotes an increase in breast cancer cell invasiveness in the laboratory. Both animal studies and population studies have reported associations between dietary fatty acids and increased risk of developing breast cancer. Obesity, which is characterized by high cholesterol, high triglycerides, and an elevated level of circulating free fatty acids, is also associated with increased risk of cancer. The free fatty acid oleic acid has previously been shown to induce migration and proliferation in breast cancer cells, as well as prolonging survival and invasion.
Generally speaking, the percentage of oleic acid in a fat does not appear to be directly correlated with the impact of the fat on the risk of breast cancer. For example, corn oil has the same level of oleic acid as walnut oil, but corn oil has been shown to promote breast cancer whereas walnut oil is thought to be protective. The influence of given oil is based on numerous factors, including the other fatty acids that make up the oil and its phytochemical and other non-oil components.
We conclude that consuming extra-virgin olive oil is probably preferable to using highly refined olive oil

مقاله (1)سرطان سینه یک بیماری بدخیم در بین زنان کشورهای غربی است. تقریبا از هر 11 زن یک زن مبتلا است .در این بیماری معمولا سلول ها بدخیم می شوند ومتاستاز را برقرارمی¬کنند متاستازتوسط ست پیچیده¬ای از مکانیسم های است که هنوز ناشناخته اند ولی نیازمند جدا شدن یک سلول از تومور اولیه ونفوذ به ماتریکس بافت وبعد رشد متمایل به توسعه را متحمل می¬شود.
یک گلیکوزیل فسفاتیدیل اینوزیتول لنگر اندازجزء لیپیدهای رفت هاستو یک آنزیم کانورتازکننده 5'-AMP به آدنوزین خارج سلولی است.نقش ژن در سرطان به آدنوزین مربوط می شود .نشان داده شده که بین بیان ژن اکتو و بخش تومور و بازگشت (عود) وابستگی وجود دارد.
ما پیشنهاد می کنیم که افزایش بیان اکتو ممکن است برقرار میکرومتاستاز در ناحیه های دور تسهیل کند.
پروتئین¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬ های CD44 یک خانواده حاضر در همه گلیکوپروتین های ترا غشایی ویک گیرنده مهم برای هیالورونان-مطالعات CD44 نشان داد که مطالعات بیشتر ممکن بشناسند ایزوفرم های متفاوتی را که به رفتارهای متاستازی وابسته اند
مقاله(2)مطالعات اجام شده در ایتالیایی شمالی ارتباط بین اسید چرب غشاء اریتروسیت و خطر سرطان سینه در سنین یائسگی را نشان می دهد. مطالعات انجام شده نشان می دهد که ارتباط بین هرمون و رژیم غذایی در سرطان سینه در سنین یائسگی موثر است.
یک مجموعه 4059 نفری از زنان یائیسه در طی 5/ 5سال مورد بررسی قرار گرفتن که از این 4059 نفر 71موردبه صورت واضح دارای سرطان بودن
آنالیز اسید های چرب غشاء این افراد نشان می دهد که افرادی که اسید چرب غشاء آنها حلقه اسید چرب اشباء نشده منفرددارد احتمال سرطان سینه بیشتر می شود .نتیجه اینکه اسید های چرب غیر اشباء درسرطان موثر هستند .در بررسی های بعدی مشاهده شده که رژیم غذایی وفعالیت هرمون(هرمون های درون ریز) نیز در سرطان موثراست .
مقاله(3)هر دو مطالعات جانوری وجمعیتی گزارش کرده اندیک همبستگی بین رژیم غذایی واسید چرب و افزایش خطر سرطان سینه وچاقی وجود دارد.مشخص شده کلسترول و تری گلیسرید بالا یک افزایش سطح چرخش اسید چرب آزاد هم بسته وجود دارد وهمچنین با افزایش خطر سرطان هم بسته است.

1) Map_ molecular & cellular proteomics plasma membrane proteomics and application in cancer Biomarker
2) Oxford journals erythrocyte membrane fatty acid
3) Food for breast cancer.com /news/oleic…

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