Green Tea: A Natural Ally Against Skin Cancer
There is significant information emerging of the benefits of Green Tea for Skin Cancer. Skin cancer is a major global health concern, and research is continually seeking effective prevention and treatment methods. One promising area of study is the role of dietary compounds, particularly polyphenols found in green tea, in combating skin cancer.
The Power of Green Tea Polyphenols
Green tea, a popular beverage consumed worldwide, is not just known for its refreshing taste but also for its potential health benefits.
Green tea is rich in polyphenols, potent antioxidants that have been shown to have significant health benefits. Studies have revealed that these polyphenols can inhibit the expression of Cyclooxygenase-2 (COX-2), an enzyme linked to inflammation and cancer 1. This inhibition is particularly effective in reducing the harmful effects of UVB radiation, a key factor in the development of skin cancer.
Topical Application for Skin Protection
Interestingly, the benefits of green tea polyphenols extend beyond ingestion. Topical application of green tea extract or EGCG, a specific type of polyphenol, can significantly reduce UVB-induced infiltration of inflammatory leukocytes and myeloperoxidase activity 2. This suggests that green tea could be used as a topical agent for everyday photo chemoprevention 3.
The Role of Other Polyphenols
While green tea polyphenols show promise, they’re not the only ones with potential skin cancer-fighting properties. For instance, curcumin I and curcumin II, polyphenols found in turmeric, have been tested on various melanoma cell lines. These compounds exhibited strong anti-inflammatory activity against COX-1 and COX-2 enzymes, further highlighting the potential of dietary compounds in skin cancer prevention and treatment 4.
EGCG, Signaling Pathways, and Cancer
One of the major active components of green tea, epigallocatechin-3-gallate (EGCG), has been reported to exhibit anticancer activity on various types of cancers.
It can alter the cancer cell cycle, development, and apoptosis by activating or inhibiting various signal pathways. 5
EGCG, Epigenetics, and Cancer
EGCG can cause epigenetic changes in cancer through DNA methylation, histone acetylation, and non-coding RNAs (microRNAs). These changes can directly regulate the expression of miRNA transcription by oncogenic and tumor-suppressor transcription factors. 5
EGCG, miRNAs, and Cancer
miRNA Interaction: Several proteins have been identified as direct interactors of miRNA by EGCG. However, the mechanisms explaining how EGCG modulates the action of miRNA are not fully understood. 5
Green Tea Extract, EGCG and squamous carcinoma
In a recent study, researchers investigated the anticancer activity of both green tea extract (GTE) and EGCG on three human squamous carcinoma cell lines. CAL-27, SCC-25, and KB. These cell lines are frequently used in cancer research, including studies on the biology, treatment, and understanding of skin cancer, particularly squamous cell carcinoma (SCC). The results were promising. Both GTE and EGCG inhibited the growth of all three cell lines, causing arrest in the S and G2/M phases of the cell cycle. Interestingly, different cell lines showed varying sensitivities to GTE and EGCG. For instance, CAL-27 cells were more sensitive to both agents than SCC-25 and KB cells. Moreover, GTE displayed a stronger inhibitory effect than EGCG alone at an equivalent concentration.
To understand the underlying mechanisms, the researchers used a newly developed technology called Pathway Array. This innovative proteomic assay allows for a global screening of changes in protein expression and phosphorylation. The assessment revealed that different signaling pathways were activated in different cell lines, suggesting a level of heterogeneity in the signaling network.
After treatment with GTE or EGCG, significant alterations were observed in a total of 21 proteins and phosphorylations across all three cell lines. The major signaling pathways affected by GTE and EGCG were the EGFR and Notch pathways, which in turn affected cell cycle-related networks.
These findings suggest that GTE and EGCG target multiple pathways or global networks in cancer cells, resulting in a collective inhibition of cancer cell growth. This points to a future direction for studying the underlying mechanisms of the chemotherapeutic and chemopreventive activities of EGCG and GTE8.
This research underscores the potential of green tea and its components in cancer prevention and treatment. However, more studies are needed to fully understand the exact molecular mechanisms of its anticancer activity 6.
You can read more here:
Liu X, Zhang DY, Zhang W, Zhao X, Yuan C, Ye F. The effect of green tea extract and EGCG on the signaling network in squamous cell carcinoma. Nutr Cancer. 2011;63(3):466-75. doi: 10.1080/01635581.2011.532901. PMID: 21391127.
Stay tuned for more updates on this exciting area of research!
Conclusion
The fight against skin cancer is multifaceted, and the role of dietary compounds like green tea polyphenols and EGCG, is becoming increasingly recognized. As we continue to explore and understand their benefits, it’s clear that these natural compounds could play a significant role in skin cancer prevention and treatment strategies. Remember, always consult with a healthcare professional before starting any new treatment regimen. It’s important to clearly state that while promising, these findings are not conclusive evidence that green tea can prevent or treat skin cancer.
References
1 Chapple K.S., Cartwright E.J., Hawcroft G., Tisbury A., Bonifer C., Scott N., Windsor A.C.J., Guillou P.J., Markham A.F., Coletta P.L., et al. Localization of Cyclooxygenase-2 in Human Sporadic Colorectal Adenomas. Am. J. Pathol. 2000;156:545–553. doi: 10.1016/S0002-9440(10)64759-1.
2 Katiyar S.K., Matsui M.S., Elmets C.A., Mukhtar H. Polyphenolic Antioxidant (-)-Epigallocatechin-3-Gallate from Green Tea Reduces UVB-Induced Inflammatory Responses and Infiltration of Leukocytes in Human Skin. Photochem. Photobiol. 1999;69:148–153. doi: 10.1562/0031-8655(1999)069<0148:PAEGFG>2.3.CO;2.
3 Mnich C.D., Hoek K.S., Virkki L.V., Farkas A., Dudli C., Laine E., Urosevic M., Dummer R. Green Tea Extract Reduces Induction of P53 and Apoptosis in UVB-Irradiated Human Skin Independent of Transcriptional Controls. Exp. Dermatol. 2009;18:69–77. doi: 10.1111/j.1600-0625.2008.00765.x.
4 Ramsewak R.S., DeWitt D.L., Nair M.G. Cytotoxicity, Antioxidant and Anti-Inflammatory Activities of Curcumins I–III from Curcuma Longa. Phytomedicine. 2000;7:303–308. doi: 10.1016/S0944-7113(00)80048-3.
5 Lee, J. H., & Kim, J. H. Epigenetic regulation of microRNA expression by epigallocatechin-3-gallate in cancer. Nutrients, vol. 12, no. 12, 2020, p. 3778, doi:10.3390/nu12123778.
6 Liu X, Zhang DY, Zhang W, Zhao X, Yuan C, Ye F. The effect of green tea extract and EGCG on the signaling network in squamous cell carcinoma. Nutr Cancer. 2011;63(3):466-75. doi: 10.1080/01635581.2011.532901. PMID: 21391127.