Lani
07-01-2010, 07:20 AM
more specific studies have been done on her2+ breast cancer cell lines by Dr. Menendez (use search function or entrez pubmed)
A key mechanism links virgin olive oil to protection against breast cancer
[Eureka News Service]
The researchers decoded a complete cascade of signals within breast tumour cells activated by virgin olive oil, and concluded that benefits include decrease in the activity of the oncogene p21Ras, changes in protein signaling pathways, stimulation of tumour cell death and prevention of DNA damage. The study was carried out in an experimental model and researchers have already begun a new study with human cell lines.
Breast cancer is the most common type of cancer in Western countries. Research carried out with animal models demonstrate that a diet rich in fats is directly related to the incidence of cancer. Some types of fats however can play a protective role against the development of these tumours. Such is the case of virgin olive oil, rich in oleic acid, a mono-unsaturated fatty acid, and containing several bioactive compounds such as antioxidants. A moderate and regular intake of virgin olive oil, characteristic of the Mediterranean diet, is associated with low incidences of specific types of cancer, including breast cancer, as well as with having a protective role against coronary diseases and other health problems.
The study carried out by UAB researchers decoded the mechanisms operating within the tumour cell and induced by the intake of olive oil, in comparison to those activated by corn oil, rich in n-6 polyunsaturated fatty acids, which increase the aggressiveness of tumours.
Scientists demonstrated that virgin olive oil is associated with higher incidences of benign breast tumours and at the same time with a decrease in the activity of the p21Ras oncogene, which spurs uncontrolled cell proliferation and stimulates the growth of tumours. In addition, olive oil suppresses the activity of some proteins, such as the AKT, essential for the survival of cells since they prevent apoptosis, the cell's "suicide" programme. Between proliferation and apoptosis in tumour cells, these effects tip the balance towards cell death, thereby slowing the growth of tumours.
Another result obtained by researchers is the protection of DNA in the cell nucleus. Cells from animals fed a diet rich in virgin olive oil contained less DNA lesions than those fed a control diet.
Scientists of the UAB Breast Cancer Study Multidisciplinary Group (GMECM) have spent over twenty years working to determine the effects fats have on breast cancer, and in particular the effects of virgin olive oil. Previous studies of the group revealed the beneficial effects of this component of the human diet on the clinical conduct of mammary tumours and on their histological grade (malignancy). Scientists also described several molecular mechanisms producing these effects and in 2004 the same group was the one to identify the four genes involved in the effects dietary fats have on experimental breast cancer. The mechanism recently discovered was published in the journal Carcinogenesis.
ABSTRACT: Dietary olive oil and corn oil differentially affect experimental breast cancer through distinct modulation of the p21Ras signaling and the proliferation-apoptosis balance
[Carcinogenesis]
Extra-virgin olive oil (EVOO) has been hypothesized to have chemopreventive effects on breast cancer, unlike high corn oil (HCO) diets that stimulate it. We have investigated mechanisms of these differential modulatory actions on experimental mammary cancer. In 7,12-dimethylbenz(a)anthracene adenocarcinomas of rats fed a high EVOO, HCO and control diets (n = 20 for each group), we have analyzed the expression and activity of ErbB receptors, p21Ras and its extracellular signal-regulated kinase (ERK) 1/2, Akt and RalA/B effectors by immunoblotting analyses. We explored the Ha-ras1 mutation status by Southern blot, mismatch amplification mutation assay and sequencing, and the 3-hydroxy-3-methylglutaryl-coenzyme A reductase and squalene synthase messenger RNA expression by real-time polymerase chain reaction. We analyzed the tumor mitotic index, proliferating cell nuclear antigen (PCNA) levels, and apoptosis through Caspase-3 analysis and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assays. Finally, we measured the 8-oxo-2'-deoxyguanosine levels. Non-parametrical statistics were used. The EVOO diet decreased Ras activation, downregulated the Ras/phosphatidyl inositol 3-kinase/Akt pathway and upregulated the Raf/Erk pathway, compared with the control. In contrast, the HCO diet did not modify Ras activity but rather enhanced the Raf/Erk pathway. The EVOO diet decreased the cleaved ErbB4 levels, compared with the HCO diet, increased apoptosis and diminished the mono-ubiquitylated PCNA levels, which is related to DNA damage. Tumors from rats fed the EVOO diet displayed a more benign phenotype, whereas those from rats fed the HCO diet were biologically more aggressive. In conclusion, high EVOO and corn oil diets exert their modulatory effects on breast cancer through a different combination of Ras signaling pathways, a different proliferation-apoptosis balance and probably distinct levels of DNA damage.
A key mechanism links virgin olive oil to protection against breast cancer
[Eureka News Service]
The researchers decoded a complete cascade of signals within breast tumour cells activated by virgin olive oil, and concluded that benefits include decrease in the activity of the oncogene p21Ras, changes in protein signaling pathways, stimulation of tumour cell death and prevention of DNA damage. The study was carried out in an experimental model and researchers have already begun a new study with human cell lines.
Breast cancer is the most common type of cancer in Western countries. Research carried out with animal models demonstrate that a diet rich in fats is directly related to the incidence of cancer. Some types of fats however can play a protective role against the development of these tumours. Such is the case of virgin olive oil, rich in oleic acid, a mono-unsaturated fatty acid, and containing several bioactive compounds such as antioxidants. A moderate and regular intake of virgin olive oil, characteristic of the Mediterranean diet, is associated with low incidences of specific types of cancer, including breast cancer, as well as with having a protective role against coronary diseases and other health problems.
The study carried out by UAB researchers decoded the mechanisms operating within the tumour cell and induced by the intake of olive oil, in comparison to those activated by corn oil, rich in n-6 polyunsaturated fatty acids, which increase the aggressiveness of tumours.
Scientists demonstrated that virgin olive oil is associated with higher incidences of benign breast tumours and at the same time with a decrease in the activity of the p21Ras oncogene, which spurs uncontrolled cell proliferation and stimulates the growth of tumours. In addition, olive oil suppresses the activity of some proteins, such as the AKT, essential for the survival of cells since they prevent apoptosis, the cell's "suicide" programme. Between proliferation and apoptosis in tumour cells, these effects tip the balance towards cell death, thereby slowing the growth of tumours.
Another result obtained by researchers is the protection of DNA in the cell nucleus. Cells from animals fed a diet rich in virgin olive oil contained less DNA lesions than those fed a control diet.
Scientists of the UAB Breast Cancer Study Multidisciplinary Group (GMECM) have spent over twenty years working to determine the effects fats have on breast cancer, and in particular the effects of virgin olive oil. Previous studies of the group revealed the beneficial effects of this component of the human diet on the clinical conduct of mammary tumours and on their histological grade (malignancy). Scientists also described several molecular mechanisms producing these effects and in 2004 the same group was the one to identify the four genes involved in the effects dietary fats have on experimental breast cancer. The mechanism recently discovered was published in the journal Carcinogenesis.
ABSTRACT: Dietary olive oil and corn oil differentially affect experimental breast cancer through distinct modulation of the p21Ras signaling and the proliferation-apoptosis balance
[Carcinogenesis]
Extra-virgin olive oil (EVOO) has been hypothesized to have chemopreventive effects on breast cancer, unlike high corn oil (HCO) diets that stimulate it. We have investigated mechanisms of these differential modulatory actions on experimental mammary cancer. In 7,12-dimethylbenz(a)anthracene adenocarcinomas of rats fed a high EVOO, HCO and control diets (n = 20 for each group), we have analyzed the expression and activity of ErbB receptors, p21Ras and its extracellular signal-regulated kinase (ERK) 1/2, Akt and RalA/B effectors by immunoblotting analyses. We explored the Ha-ras1 mutation status by Southern blot, mismatch amplification mutation assay and sequencing, and the 3-hydroxy-3-methylglutaryl-coenzyme A reductase and squalene synthase messenger RNA expression by real-time polymerase chain reaction. We analyzed the tumor mitotic index, proliferating cell nuclear antigen (PCNA) levels, and apoptosis through Caspase-3 analysis and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assays. Finally, we measured the 8-oxo-2'-deoxyguanosine levels. Non-parametrical statistics were used. The EVOO diet decreased Ras activation, downregulated the Ras/phosphatidyl inositol 3-kinase/Akt pathway and upregulated the Raf/Erk pathway, compared with the control. In contrast, the HCO diet did not modify Ras activity but rather enhanced the Raf/Erk pathway. The EVOO diet decreased the cleaved ErbB4 levels, compared with the HCO diet, increased apoptosis and diminished the mono-ubiquitylated PCNA levels, which is related to DNA damage. Tumors from rats fed the EVOO diet displayed a more benign phenotype, whereas those from rats fed the HCO diet were biologically more aggressive. In conclusion, high EVOO and corn oil diets exert their modulatory effects on breast cancer through a different combination of Ras signaling pathways, a different proliferation-apoptosis balance and probably distinct levels of DNA damage.