STAT3-IN-10 (A11) is an inhibitor of STAT3 that directly binds to STAT3 SH2 domain, inhibits tumor cell growth and induces apoptosis in cancer cells (IC 50 = 5.18 μM) [1].

STAT3-IN-10 (A11) (48 h) shows IC 50 values of 0.67, 0.77, 1.24 μM against MDA-MB-231, MDA-MB-468, HepG2 cells, respectively [1]. STAT3-IN-10 (A11) directly binds to the STAT3 SH2 domain [1]. STAT3-IN-10 (A11) (0-3 μM, 24 h) inhibits the phosphorylation of STAT3 and its downstream target proteins and has a good selectivity against the tumor suppressor STAT1 [1]. STAT3-IN-10 (A11) (0-4 μM, 24 h) induces apoptosis in cancer cells [1]. STAT3-IN-10 (A11) (0-4 μM, 24 h) dose-dependently causes a significant S phase arrest in MDA-MB-231 cells [1]. Cell Viability Assay [1] Cell Line: Breast cancer cell lines: MDA-MB-231 and MDA-MB-468; human liver carcinoma cell line: HepG2. Concentration: Incubation Time: 48 h, re-incubated for 4 h (MDA-MB-468, MDA-MB-231) and 1h (HepG2). Result: Showed IC 50 values of 0.67, 0.77, 1.24 μM against MDA-MB-231, MDA-MB-468, HepG2 cells, respectively. Western Blot Analysis [1] Cell Line: MDA-MB-231. Concentration: 0, 0.75, 1.5 and 3.0 μM. Incubation Time: 24 h. Result: Decreased the STAT3-Y705 phosphorylation without affecting the total amount of STAT3 protein and decreased the expression of STAT3 target genes, including C-Myc and Cyclin D1 in a dose-dependent manner. Had little impact on the level of STAT1 and its phosphorylation on Tyr701. Apoptosis Analysis [1] Cell Line: MDA-MB-231. Concentration: 0, 1, 2, and 4 μM. Incubation Time: 24 h. Result: Induced the apoptosis in MDA-MB-231 cells in a concentration-dependent manner Cell Cycle Analysis [1] Cell Line: MDA-MB-231. Concentration: 0, 1, 2, and 4 μM. Incubation Time: 24 h. Result: Could dose-dependently cause a significant S phase arrest in MDA-MB-231 cells

STAT3-IN-10 (A11) (5 and 10 mg/kg; IP; once a day, 21 days) inhibits the growth of human xenograft tumor in vivo [1]. Animal Model: Five weeks old female BALB/c nude mice (16–18g) bearing inoculation of human breast cancer cells MDA-MB-231 [1]. Dosage: 5 and 10 mg/kg Administration: IP, once a day, 21 days Result: Inhibited the growth of human xenograft tumor in vivo without apparent body-weight loss for treated mice and inhibited the levels of p-STAT3 in tumor tissues.