The role of natural compounds in rat mammary cancer: the beneficial effects of a Santolina chamaecyparissus L. aqueous extract

Abstract

Breast cancer is the most diagnosed cancer among women, and a leading cause of death worldwide. Santolina chamaecyparissus L. is a plant with multiple health benefits, includ- ing anticancer and anti-diabetic properties. This study aimed to assess the chemopreven- tive effects of S. chamaecyparissus aqueous ex- tract (SCE) in an animal model of mammary cancer. A total of 28 four-week-old female Wistar rats were divided into four groups: control, MNU-induced (IND), SCE-supple- mented (SCE), and SCE+IND. SCE was added to drinking water (12.72 mg/kg body weight) ad libitum. MNU was administered via the in- traperitoneal route at 50 days of age. Weekly monitoring of body weight, food/drink intake, humane endpoints, and number of mammary tumours were recorded. Twenty weeks after MNU administration, animals were sacrificed by anaesthetic overdose and a necropsy was performed. Blood samples were used to de- termine blood count and serum biochemistry analysis, while kidney and liver samples were analysed for oxidative stress. Tumour sam- ples were collected for gene expression and histology studies. SCE chemical composition was analysed by LC-MS and contained 19 phenolic compounds, with the most abundant being myricetin-O-glucuronide and 1,3-O-di- caffeoylquinic acid. Two animals in the IND group were sacrificed due to exceeding the humane endpoint limits. SCE supplementa- tion delayed mammary tumour development, reducing its volume and weight. SCE had a positive impact on haematological parame- ters, particularly the neutrophil-lymphocyte ratio (P=0.026). No significant differences were observed in serum biochemistry, except for creatinine kinase MB, or in oxidative stress markers. Gene expression analysis showed significantly reduced VEGF expression levels (P=0.0158) in tumours from SCE+IND. These findings suggest that SCE is deserving of further study to identify the individual com- pounds and to understand its influence on an- imal models during cancer development.