Scope Aberrant activation of the Wingless-type mouse mammary tumor virus integration site family (Wnt)/β-catenin signaling pathway is the most common modification and CYN-154806 often considered a hallmark of colorectal cancer (CRC). dietary triterpene lupeol results in a dose dependent i) decrease in cell viability ii) induction of apoptosis iii) decrease in colonogenic potential iv) decrease in β-catenin transcriptional activity and v) decrease in the expression of Wnt target genes. Most importantly lupeol was observed to inhibit the translocation of β-catenin from the cytoplasm to the nucleus. Importantly all these effects of lupeol were restricted to cells that harbor constitutively active Wnt/β-catenin signaling while negligible effects were observed in cells that lack constitutively JAG2 active Wnt/β-catenin signaling. Further we also demonstrate that inhibition of Wnt signaling in cells with constitutive active Wnt/β-catenin results in loss of lupeol efficacy while inducing Wnt signaling CYN-154806 sensitizes the CYN-154806 cells to inhibitory effects of lupeol. Conclusions In summary our data strongly advocate CYN-154806 the efficacy of lupeol against CRC CYN-154806 cells that exhibit constitutively active Wnt/β-catenin signaling. 1 INTRODUCTION Colorectal cancer (CRC) is the third most common cause of cancer related deaths in the United States [1-3]. High mortality rates and poor prognosis of the disease advocate the need for the development of novel approaches to prevent the initiation of premalignant lesions or their progression to cancer or cancer recurrence. Wnt/β-catenin signaling pathway is known to play an important role in normal development stem cell maintenance and various malignancies including CRC [4-6]. In the active state β-catenin an important transcriptional regulator is known to interact with members of the T-cell factor (TCF) family CYN-154806 of transcription factors to induce the transcription of important downstream target genes many of which are involved in proliferation and cellular transformation [5 7 8 The hallmark of active Wnt signaling i.e. the nuclear localization of β-catenin has been observed in a majority of CRC cases [9 10 Also a vast majority of CRC cases arise on account of an activating mutation in the Wnt/β-catenin signaling pathway [4 11 Aberrant activation in this pathway due to truncating mutations in APC is recognized as a central player in colon cancer . Other common molecular alterations in tumor cells leading to disruption of β-catenin degradation are mutations that inactivate axin or activate β-catenin itself . These alterations result in an accumulation of β-catenin in the nucleus resulting in transcription of downstream targets. Lupeol a dietary triterpene found in various fruits (olives mangoes grapes figs) vegetables (green peppers) and in medicinal herbs (and [14 16 18 In our efforts to identify bioactive food components that target Wnt/β-catenin signaling we wanted to study the effect of lupeol on CRC since a majority of CRCs exhibit aberrant mutations in Wnt/β-catenin signaling. We previously showed the effects of lupeol on melanoma cells that exhibit constitutively active Wnt/β-catenin signaling pathway . In this study we demonstrate that lupeol has a greater efficacy against CRC cells that harbor constitutive activation of Wnt/β-catenin signaling pathway (DLD 1 HCT 116) as compared to the cells that lack constitutive activation of this pathway (RKO). 2 MATERIALS AND METHODS 2.1 Cell lines and cell culture The CRC cell lines DLD 1 and HCT 116 were obtained from the American Type Culture Collection (ATCC). The RKO cells were kindly provided by Dr. Bert Vogelstein (The Johns Hopkins University School of Medicine). Cells were maintained in DMEM supplemented with 10% fetal bovine serum (FBS) and 1% antibiotic-antimycotic solution (PSM) including penicillin streptomycin and amphotericin B under regular growth circumstances (5% CO2 37 humidified atmosphere). 2.2 Treatment of cells with lupeol A share solution of lupeol (10 mM) was made by dissolving it in warm ethanol and diluting in DMSO inside a 1:1 percentage. The cells (50% confluent) had been treated with lupeol (20-40 μM) for 48 h in full cell media. All treatment protocols and settings were ready as described  previously. 2.3 Cell proliferation assay The result of lupeol for the viability of melanoma cells was dependant on 3-(4.