Background: Honey has been shown to have anti-cancer effects, but the mechanism behind these effects is not fully understood. We investigated the role of Malaysian jungle Tualang honey (TH) in modulating the hematological parameters, estrogen, estrogen receptors (ER1) and pro and anti-apoptotic proteins expression in induced breast cancer in rats.
Methods: Fifty nulliparous female Sprague-Dawley rats were used and grouped as follows: Group 0 (healthy normal rats control), Group 1 (negative control; untreated rats), Groups 2, 3 and 4 received daily doses of 0.2, 1.0 and 2.0 g/kg body weight of TH, respectively. The rats in groups 1, 2, 3, 4 were induced with 80 mg/kg of 1-methyl-1-nitrosourea (MNU). TH treatment in groups 2, 3 and 4 was started one week prior to tumor induction and continued for 120 days.
Results: The TH-treated rats had tumors of different physical attributes compared to untreated negative control rats; the tumor progression (mean 75.3 days versus 51.5 days); the incidence (mean 76.6% versus 100%); the multiplicity (mean 2.5 versus 4 tumor masses per rat); the size of tumor mass (mean 0.41 cm versus 1.47 cm [p < 0.05]) and the weight of the tumor mass (mean 1.22 g versus 3.23 g; [p < 0.05]). Histological examinations revealed that cancers treated with TH were mainly of grades I and II compared with the non-treated control, in which the majority were of grade III (p < 0.05). TH treatment was found to modulate hematological parameters such as Hb, RBCs, PCV, MCV, RDW, MCHC, polymorphs and lymphocytes values. TH treatment groups were found to have a lower anti-apoptotic proteins (E2, ESR1 and Bcl-xL) expression and a higher pro-apoptotic proteins (Apaf-1 and Caspase-9) expression at serum and on cancer tissue level (p < 0.05).
Conclusion: Tualang Honey alleviates breast carcinogenesis through modulation of hematologic, estrogenic and apoptotic activities in this experimental breast cancer animal model. Tualang Honey may be used as a natural 'cancer-alleviating' agent or as a supplement to chemotherapeutic agents.
Keywords: Anti-cancer effect; Apaf-1; Estrogen receptor 1; Experimental breast cancer; Honey effect on hematological Parameters; Tualang honey.