Synthesis and biological evaluation of novel N, N'-diarylurea derivatives as potent antibacterial agents against MRSA.
作者: Xiaonan Du ; Minghua Wang ; Xinxin Hu ; Tongying Nie ; Mei Zhu ; Guoning Zhang ; Xuefu You ; Yucheng Wang
A series of new N, N'-diarylurea derivatives were designed and synthesized, some of which exhibited potent antibacterial activity against the drug-susceptible and drug-resistant Gram-positive strains. Especially, compounds 2c, 2g-2l showed broader antibacterial spectrum and more potent antibacterial activity (MIC = 0.30-2.72 μM) against MRSA and MRSE than the control levofloxacin (MIC = 0.69-22.14 μM). In addition, compounds 2c, 2g, 2h and 2l exhibited much better antibacterial activity (MIC = 1.29-2.86 μM) against VRE (E. faecium) than sorafenib (MIC = 275.37 μM), PK150 (MIC = 5.07-10.13 μM) and SC78 (MIC = 2.40-4.79 μM). More importantly, the low cytotoxicity of compounds on cell lines HeLa and HepG2 implied a relatively wide therapeutic window, which was of high importance for further study.
2018-01-01·Cell death discovery2区 · 医学
Two novel SHP-1 agonists, SC-43 and SC-78, are more potent than regorafenib in suppressing the in vitro stemness of human colorectal cancer cells.
2区 · 医学
作者: Shin-Yi Chung ; Yen-Hsi Chen ; Pei-Rong Lin ; Ta-Chung Chao ; Jung-Chen Su ; Chung-Wai Shiau ; Yeu Su
Signal transducer and activator of transcription 3 (STAT3) has been shown to play a critical role in the maintenance of cancer stem cells (CSCs). Hence, the inhibition of STAT3 signaling has been suggested to be a viable therapeutic approach for cancers. Moreover, the efficacy of combinations of chemotherapeutic drugs and napabucasin, a small-molecule STAT3 inhibitor, have been assessed in various clinical trials, including those involving patients with metastatic colorectal cancer (CRC). Two recently developed small-molecule STAT3 inhibitors, SC-43 and SC-78, which can stimulate SHP-1 to inactivate STAT3, were found to have anti-tumor activity. In this study, the inhibitory effects of SC-43, SC-78, and regorafenib (a reference drug) on cell viability, STAT3 phosphorylation, and various stemness properties [e.g., sphere-forming and soft agar colony-forming abilities, CD133+/CD44+ (stem cell-like) subpopulations, and the expression of several CSC markers] were examined for both HCT-116 and HT-29 human CRC cells. We found that SC-43 and SC-78 but not regorafenib inhibited constitutive and IL-6-induced STAT3 phosphorylation in HCT-116 and HT-29 cells, respectively. Moreover, SC-43 and SC-78 were more potent than regorafenib in suppressing the stemness properties (except stem cell-like subpopulations) of these cells. As expected, SHP-1 knockdown almost completely abolished the suppressive effects of SC-43 and SC-78 on the sphere formation in both cell lines. Furthermore, SC-43 and SC-78 showed synergistic inhibitory effects with oxaliplatin and/or irinotecan on sphere formation. Overall, our results suggest that SC-43 and SC-78 are potent STAT3 inhibitors that may potentially be used in combination therapy for CRC.
2016-07-01·Scientific Reports3区 · 综合性期刊
Disrupting VEGF-A paracrine and autocrine loops by targeting SHP-1 suppresses triple negative breast cancer metastasis
Patients with triple-negative breast cancer (TNBC) had an increased likelihood of distant recurrence and death, as compared with those with non-TNBC subtype. Regorafenib is a multi-receptor tyrosine kinase (RTK) inhibitor targeting oncogenesis and has been approved for metastatic colorectal cancer and advanced gastrointestinal stromal tumor. Recent studies suggest regorafenib acts as a SHP-1 phosphatase agonist. Here, we investigated the potential of regorafenib to suppress metastasis of TNBC cells through targeting SHP-1/p-STAT3/VEGF-A axis. We found a significant correlation between cancer cell migration and SHP-1/p-STAT3/VEGF-A expression in human TNBC cells. Clinically, high VEGF-A expression is associated with worse disease-free and distant metastasis-free survival. Regorafenib induced significant anti-migratory effects, in association with downregulation of p-STAT3 and VEGF-A. To exclude the role of RTK inhibition in regorafenib-induced anti-metastasis, we synthesized a regorafenib derivative, SC-78, that had minimal effect on VEGFR2 and PDGFR kinase inhibition, while having more potent effects on SHP-1 activation. SC-78 demonstrated superior in vitro and in vivo anti-migration to regorafenib. Furthermore, VEGF-A dependent autocrine/paracrine loops were disrupted by regorafenib and SC-78. This study implies that SHP-1/p-STAT3/VEGF-A axis is a potential therapeutic target for metastatic TNBC, and the more potent SC-78 may be a promising lead for suppressing metastasis of TNBC.