Camellia Sinensis and its Potential Role in Breast Cancer Prevention and Management: A Review

Green tea derived from  leaves of the Camellia sinensis plant, belonging to the family Theaceae, is widely cultivated evergreen shrub whose leaves and buds are the source of one of the most consumed beverages globally. Originating from East Asia, C. sinensis has been traditionally used not only for its refreshing properties but also for its medicinal benefits. The plant is rich in bioactive compounds such as caffeine , xanthine’s, theobromine, and tannins , including flavonoids, polyphenols, fats and vitamin C. Tea extracts exhibit numerous properties , including  antitumor, antioxidant, anticoagulant , antiviral etc.

Among these, the antitumor potential of green tea has gained significant attention in recent years, particularly in relation to breast cancer, which remains one of the most prevalent malignancies affecting women globally. The major polyphenol, epigallocatechin-3-gallate (EGCG), has been extensively studied for its ability to inhibit cancer cell proliferation, induce apoptosis, suppress angiogenesis, and interfere with metastasis.

 METHODOLOGY OF LITERATURE REVIE

A comprehensive literature search was carried out using databases such as PubMed, Scopus, ScienceDirect, and Google Scholar. Keywords are  used for the search. Studies involving in vitro, in vivo, and clinical evaluations of green tea or its bioactive compounds against breast cancer were prioritized.

Botanical aspect;

Scientific Classification:

Table:1-classification

Table 2-Common names

DESCRIPTION

Camellia sinensis is an evergreen shrub or small tree belonging to the family Theaceae, widely cultivated for its leaves and buds, which are processed to produce tea – one of the most consumed beverages worldwide. Leaves are simple, alternate, elliptic to lanceolate, 4–15 cm long and 2–5 cm wide, with finely serrated margins and glossy dark-green surface. Young leaves and buds are most commonly harvested for tea production. Flowers are white, fragrant, bisexual, solitary or in small clusters, about 2.5–4 cm in diameter, with 5–7 petals and numerous yellow stamens. Blooming usually occurs in autumn to winter. Fruits are small, round to oval capsule (1–2 cm in diameter), usually containing 1–3 seeds. Deep taproot system that helps the plant absorb water and nutrients, contributing to its drought tolerance. The  growth Conditions of Camellia sinensis Prefers subtropical to tropical climates, well-drained acidic soils, and elevations ranging from lowlands to high altitudes (up to 2,000 m). Shade and rainfall greatly influence leaf quality and flavor.

Figure number:1-Green tea

CHEMICAL CONSTITUENTS

Green tea contains a wide variety of bioactive compounds responsible for its medicinal and therapeutic properties the major groups are polyphenols, alkaloids, amino acids, vitamins, minerals and trace elements, chlorophyll, volatile organic compounds, carbohydrates and proteins. Polyphenols include epigallocatechin-3-gallate (EGCG), epigallocatechin (EGC), epicatechin-3-gallate (ECG), epicatechin (EC). Alkaloids include Caffeine (2–5%), theobromine and theophylline. L-Theanine is a unique amino acid in tea.

ANTI BREAST CANCER ACTIVITY OF CAMELLIA SINENSIS: PRECLINICAL EVIDENCE

Camellia sinensis is widely recognized for its potential protective and therapeutic effects against breast cancer, mainly attributed to its rich content of polyphenolic compounds, especially catechins such as epigallocatechin gallate (EGCG) [19]. These bioactive constituents exert anticancer effects by inhibiting breast cancer cell proliferation, inducing apoptosis, and modulating key molecular pathways involved in tumor growth and progression [20].

Experimental evidence suggests that Camellia sinensis extracts interfere with estrogen-related signaling and suppress the activation of growth-promoting receptors in breast cancer cells. Green tea polyphenols have also been reported to inhibit angiogenesis and metastasis by downregulating vascular endothelial growth factors and matrix metalloproteinases, thereby limiting tumor expansion and invasion [21]. Both in vitro and in vivo studies consistently demonstrate that green tea constituents regulate cell cycle progression and enhance programmed cell death in malignant breast tissues [22].

In addition to direct anticancer activity, Camellia sinensis exhibits strong antioxidant and anti-inflammatory properties, which contribute to the protection of normal tissues and reduction of oxidative stress associated with breast carcinogenesis. Animal studies have shown that supplementation with green tea extract reduces tumor volume, improves antioxidant enzyme levels, and minimizes histopathological damage in breast tissue. When used as an adjunct to conventional anticancer therapies, Camellia sinensis has been reported to enhance therapeutic efficacy while reducing treatment-related toxicity.

CONCLUSION

Camellia sinensis demonstrates considerable potential as a complementary therapeutic agent in the prevention and management of breast cancer. Its rich composition of bioactive polyphenols, particularly catechins such as epigallocatechin gallate (EGCG), contributes to a broad spectrum of pharmacological activities including antioxidant, anti-proliferative, pro-apoptotic, and anti-inflammatory effects. Experimental studies provide strong evidence of its ability to inhibit breast cancer cell growth, regulate cell cycle progression, suppress angiogenesis, and induce programmed cell death in malignant cells.

Beyond direct anticancer activity, Camellia sinensis plays a protective role by reducing oxidative stress and inflammation, thereby limiting DNA damage and supporting normal cellular function. Preclinical investigations also suggest that green tea constituents may enhance the effectiveness of conventional chemotherapeutic agents while reducing therapy-associated toxicity. These findings support the potential role of Camellia sinensis as a safe and effective complementary approach in breast cancer management. However, further large-scale clinical trials and detailed molecular studies are required to confirm its clinical efficacy, establish optimal dosing strategies, and ensure long-term safety before its integration into evidence-based breast cancer therapy.

ACKNOWLEDGEMENT

The author of this manuscript express sincere gratitude to the National college of Pharmacy, KUHS, for providing the research facilities and the faculty members for their support and encouragement throughout the study.

CONFLICT OF INTEREST

There is no conflict of interest to be declared.

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