DELTA-TOCOTRIENOLS CAN SUPPORT
INHIBITION OF CELL PROLIFERATION
ATTENUATION OF TUMOR INVASION AND METASTASIS
INCREASE OF miR-451 EXPRESSIONS
REPRESSED EXPRESSION OF MMP-9 &Upa PROTEINS
Introduction to Prostate Cancer and TRF
Prostate cancers are caused when the cells of the prostate gland start to multiply uncontrollably. Almost all kinds of prostate cancer are adenocarcinomas while other types of prostate cancers include small cell carcinomas, neuroendocrine tumors, sarcomas, and transitional cell carcinomas. It is the most commonly occurring cancer in men along with skin cancer. It has been estimated that in the United States of America,around 191,930 men will be diagnosed with prostate cancer and 33,330 people will die suffering from prostate cancer, in 2020 alone! Prostate cancer is the 2nd leading cause of cancer-related deaths in the United States.
In this study, a combination of two isomers of Vitamin E, Delta-Tocotrienols, and Gamma-Tocopherols was investigated for their anticancer properties against prostate cancer cells. Delta-Tocotrienols have been observed to demonstrate the most potent anticancer activities. Hence, in this study it has been investigated if the combination of both the isomers strengthens the inhibitory effects Delta-Tocotrienols on prostate cancer cell growth.
How does Tocotrienol-Rich Fraction (TRF) fight Prostate Cancer?
In the study, it was observed that all the isomers of Vitamin E, especially Gamma-Tocotrienol significantly suppressed the proliferation of LNCaP and PC-3 cancer cells. Delta-Tocotrienol, on the other hand, showed incredible potency in suppressing the cell proliferation and growth of LNCaP cells. It was also observed that Gamma-Tocotrienols induced apoptosis in the LNCaP cells. The order of inhibitory effect was as follows, γ-T3>δ-T3>β-T3>γ-T>δ-T≈α-T3≈α-T≈β-T (where ‘T’ stands for Tocopherols and T3 stands for Tocotrienols). Evidently, Tocotrienols, especially the Delta and the Gamma isoforms showed many potent anticancer activities as compared to Tocopherols.
Gamma-Tocotrienols induced apoptosis by the activation of pro-caspases and the presence of the sub-G1 cell population. Investigation of the effects of TRF on the pro-survival genes demonstrated that the induced apoptosis or cell death was associated with the suppression of EGF-R, NF-kB, and Id family proteins (Id1 and Id3). Also, Gama-Tocotrienol treatment suppressed the mesenchymal markers and restored the E-cadherin and gamma-catenin expression, which was associated with suppression of cell invasion capability.
To conclude, the study and data showed that the antiproliferative effects of Gamma-Tocotrienols function through multiple-signaling pathways, and for the first time, the anti-invasion and chemosensitization effect of Gamma-Tocotrienols against PCa cells was observed.
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