Fig 2: Schematic representation of anticancer activity through decreased BCSC. Tumor suppressive role of PTEN, whose gain in responding to UA decreases the fraction of CSC by downregulating the expression of AGO2 to inactivate the FAK/PI3K/Akt/mTOR and c-Myc signaling pathway. The model also suggests that UA decreased the AGO2-mediated biogenesis of miR-9 and -221 that contribute to the reduction in slug and vimentin, leading to the inhibition of breast cancer invasion and migration during EMT.

Fig 3: UA activates PTEN to modulate the FAK/PI3K/Akt signaling pathway: (A) Breast cancer cell lines were treated with UA for 48 h. Western blot analysis with antibodies to tumor progression-relevant proteins as indicated. GAPDH was used to normalize the amount of protein in each lane. (B) Incubation of breast cancer cells with UA (30 µM) significantly decreases AGO2. (C) Increased PTEN negatively regulates the expression levels of (D) FAK and (E) PI3-kinase p110 (PI3K), and inactivates the phosphorylated (activated) forms of (F) PI3K (p-P85aTyr467/Tyr199), (G) Akt (p-AktSer473), and (H) mTOR (p-mTOR2481), and reduced level of (I) c-Myc in both cells treated with UA. Densitometric analyzes for Western blot were performed as described in Materials and Methods. Data are shown as mean ± SD for three independent experiments. * p < 0.05; ** p < 0.01; *** p < 0.001 vs. control group (Ctrl, 0 µM).

Fig 4: Effects of MI on the PTEN activity in vitro. The PTEN enzyme was incubated with different concentrations of MI (0–1000 µM). The PTEN activity was detected by a commercial Malachite Green Assay Kit as described in Methods. The relative PTEN activities are expressed as the mean ± SD (n = 3 independent experiments); Values not sharing a common letter are significantly different (p < 0.05).

Fig 5: Effects of the myo-inositol (MI) on the expressions of PI3K, AKT, and PTEN, and the phosphorylation of AKT in Hs68 cells. After being treated with various concentrations of MI and LY294002 for five days, the cell lysates were obtained. The protein expressions or AKT phosphorylation level in the cell lysates were detected by the Western blot method as described in Methods. (a) Western blot Images; (b) Western blot quantification results (n = 3 independent experiments). Values (mean ± SD) not sharing a common letter are significantly different (p < 0.05).