To study the association of membrane lipid component total choline (tCho) and membrane protein β-catenin concentrations with the expression of hormonal receptor (ER, PR, Her2neu) status in breast cancer patients.The present study was performed with a hypothesis that there is an association between molecular pathway (Wnt regulated β-catenin translocation), tCho synthesis and expression of hormonal receptors like estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor (Her2neu) in breast cancer. Twenty patients with histopathologically proven infiltrating ductal carcinoma (IDC) were recruited. In vivo proton (¹H) magnetic resonance spectroscopy (MRS) was carried out using a point resolved spectroscopy (PRESS) sequence with water and lipid suppression (TR=1500 ms; TE=100 ms; total acquisition time = 3.18 minutes) and tCho concentration was calculated as reported earlier¹. Tissue samples were collected and snap frozen in liquid nitrogen immediately after surgery from same patients who underwent MRS. Tissue lysates (cytosolic and nuclear fractions) were prepared and ELISA was carried out as per the guidelines of the manufacturer (Cloud-clone Corp). Immunohistochemistry (IHC) was carried out for determining the receptor status (ER, PR and Her2neu) of patients. Wilcoxon matched pairs two tailed test and Spearman’s rank analysis was used to calculate the significance and correlations. A p-value of ˂0.05 was considered significant. Institutional ethical committee approved the study, and written informed consents were obtained from all patients.Our data demonstrated that tCho concentration of breast cancer patients ranged from 1.98-6.74 mmol/Kg (median = 4.22) which was higher than the benign and normal breast tissue ¹. The increase in tCho was related to the increased membrane turnover essential for cellular proliferation during malignancy. Table 1 presents the concentration of β-catenin (both cytosolic and nuclear fractions) and tCho in patients categorized based on expression of hormone receptors (ER, PR and Her2neu). It was observed that the nuclear β-catenin expression was statistically significantly higher compared to its cytosolic expression in IDC patients (Figure 1a). This may be attributed to the translocation of β-catenin from cytoplasm to the nucleus where it binds with the cell cycle regulators like cyclin D1 and myc leading to increased cellular proliferation². Further, our study showed a positive correlation between both cytosolic and nuclear β-catenin with tCho concentration (Figure 2a and 2b). It was reported that β-catenin increases the activity of Phospholipase D (PLD)³ which is a ubiquitous hydrolytic enzyme involved in phosphocholine biosynthetic pathway. This increased activity of PLD may enhance the tCho synthesis and thereby higher concentration of tCho was seen. Further, our results showed that patients with PR- receptor status had a significantly higher cytosolic β-catenin concentration compared to PR+ breast tumors (Figure 1b). However, there was no significant difference in tCho and β-catenin (cytosolic and nuclear) concentrations of different molecular receptors i.e., PR+ vs. PR-, ER+ vs. ER- and Her2neu+ vs. Her2neu- of patients (see Table 1). It has been shown that progesterone hormone inhibits the Wnt/β-catenin signaling pathway in PR+ tumors⁴. Hence, the absence of progesterone in PR- breast tumors may lead to activation of Wnt pathway which is manifested with increase in the cytoplasmic β-catenin expression in these patients. Present study demonstrated that tCho, β-catenin and PR play critical role in breast cancer progression. Further, the association between the quantitatively determined β-catenin and tCho concentration indicates a link between these two molecular pathways. The association of β-catenin and PR- breast tumors indicates the role of progesterone in regulating the expression of a major oncogene in breast cancer. Further study carried out in large number of patients might help in finding a more appropriate target for breast cancer treatment.