Fig 2: (a) Immunohistochemical staining of MCF-7 cell line for GGT. (b) Fluorescence image of MCF-7 cells obtained after administration of gGlu-HMRG. A differential interference contrast (DIC) image (left), a gGlu-HMRG fluorescence image (middle), and an image of cells pretreated with siRNA targeting GGT before application of gGlu-HMRG (right). (c) Time-dependent change of fluorescence intensity in MCF-7 cell line and MCF-7 cell line pretreated with siRNA targeting GGT. (d~f) Time-dependent fluorescence images of various breast tumor specimens [invasive ductal carcinoma (d), DCIS (e), intraductal papilloma (f)] after administration of gGlu-HMRG probe. In each of the specimens shown in (d–f), the time-dependent fluorescence intensities were measured at tumor lesions, normal mammary gland regions and fat (right column). (g, h) Comparisons of fluorescence localization (d and e) with pathological HE staining of the same specimen. (g) The cancer region is enclosed by a dotted line in the HE-staining image. Areas of increased fluorescence coincided well with pathologically cancerous region. Red arrows in (h) show fluorescence-positive area and malignant lesions. (i) Comparison of fluorescence increases (FI) after administration of gGlu-HMRG in breast lesions and normal tissues.

Fig 3: (A) Effect of SHP-1 on intracellular ROS. Cells were treated with SHP-1 (10, 20, 50, and 100 µM) for 2 hr. Then 0.75 M ethanol was added and incubated for 24 hr. DCFH-DA was added and reacted for 20 min. Cells were washed with PBS three times and observed under a fluorescent inverted microscope. a, The blank group (HepG2/CYP2E1 cells without treatment); b, the control group (HepG2/CYP2E1 cells with ethanol treatment only); c–f, 10–100 µM SHP-1. (B) Effect of SHP-2 on intracellular ROS. a, the blank group; b, the control group; c–f, 10–100 µM SHP-2. (C) Effect of SHP-1 on SOD activity. Values are mean ± SD (n = 3). (D) Effect of SHP-2 on SOD activity. Values are mean ± SD (n = 3). (E) Effect of SHP-1 on GSH. Values are mean ± SD (n = 3). (F) Effect of SHP-2 on GSH. Values are mean ± SD (n = 3). (G) Effect of SHP-1 on GGT activity. Values are mean ± SD (n = 3). (H) Effect of SHP-2 on GGT activity. Values are mean ± SD (n = 3). (I) Effect of SHP-1 on the expressions of SOD, GSH, and GGT. Cells were treated with SHP-1 (20, 50, and 100 µM) for 2 hr. Then, 0.75 M ethanol was added and incubated for 24 hr. SOD, GSH, and GGT levels were detected by Western blot. GAPDH was used as internal control. (J) Effect of SHP-2 on the expressions of SOD, GSH, and GGT. ### p < .001 represented the control group vs. the blank group. *p < .05 and ***p < .001 vs. the control group

Fig 4: Gamma-glutamyl transpeptidase (GGT) expression in canine mammary gland tumor tissues. GGT mRNA levels in the tumor tissues were compared with their peritumoral control tissues (A). Red and blue symbols mean the malignant (n=12) and benign (n=5) tumors, respectively. An asterisk indicates statistical significance (P<0.05). The representative immunohistochemistry images of the tumoral area (+++) and peritumoral control area (-) are shown as B and C. A scale bars mean 250 µm (white) and 20 µm (black).