Combination of ERK2 and STAT3 Inhibitors Promotes Anticancer Effects on Acute Lymphoblastic Leukemia Cells

STAT3 Signaling in Breast Cancer: Multicellular Actions and Therapeutic Potential

Simple Summary

Many signaling pathways are overactive in breast cancer, and among them is the STAT3 signaling pathway. STAT3 is activated by secreted factors within the breast tumor, many of which are elevated and correlate to advanced disease and poor survival outcomes. This review examines how STAT3 signaling is activated in breast cancer by the proinflammatory, gp130 cytokines, interleukins 6 and 11. We evaluate how this signaling cascade functions in the various cells of the tumor microenvironment to drive disease progression and metastasis. We discuss how our understanding of these processes may lead to the development of novel therapeutics to tackle advanced disease.

Abstract

Interleukin (IL)-6 family cytokines, such as IL-6 and IL-11, are defined by the shared use of the gp130 receptor for the downstream activation of STAT3 signaling and the activation of genes which contribute to the “hallmarks of cancer”, including proliferation, survival, invasion and metastasis. Increased expression of these cytokines, or the ligand-specific receptors IL-6R and IL-11RA, in breast tumors positively correlate to disease progression and poorer patient outcome. In this review, we examine evidence from pre-clinical studies that correlate enhanced IL-6 and IL-11 mediated gp130/STAT3 signaling to the progression of breast cancer. Key processes by which the IL-6 family cytokines contribute to the heterogeneous nature of breast cancer, immune evasion and metastatic potential, are discussed. We examine the latest research into the therapeutic targeting of IL-6 family cytokines that inhibit STAT3 transcriptional activity as a potential breast cancer treatment, including current clinical trials. The importance of the IL-6 family of cytokines in cellular processes that promote the development and progression of breast cancer warrants further understanding of the molecular basis for its actions to help guide the development of future therapeutic targets.

A natural acylphloroglucinol triggered antiproliferative possessions in HEL cells by impeding STAT3 signaling and attenuating angiogenesis in transgenic zebrafish model

Leukemia is responsible for a reason of death, globally. Even though there are several treatment regimens available in the clinics against this disease, a perfect chemotherapeutic agent for the same is still under investigation. Natural plant-derived secondary metabolites are used in clinics to treat leukemia for better benefits with reduced side-effects. Likely, several bioactive compounds from Callistemon sp. were reported for their bioactive benefits. Furthermore, acylphloroglucinol derivatives from Callistemon salignus, showed both antimicrobial and cytotoxic activities in various adherent human cancer cell lines. Thus, in the present study, a natural acylphloroglucinol (2,6-dihydroxy-4-methoxyisobutyrophenone, L72) was tested for its antiproliferative efficacy in HEL cells. The MTT and the cell cycle analysis study revealed that L72 treatment can offer antiproliferative effects, both time and dose-dependent manner, causing G₂/M cell cycle arrest. The western blot analysis revealed that L72 treatment triggered intrinsic apoptotic machinery and activated p21. Likewise, L72 could downregulate the gene expressions of XIAP, FLT3, IDH2, and SOD2, which was demonstrated by qPCR analysis, thus promoting its antiproliferative action. The L72 could impede STAT3 expression, which was evidenced by insilico autodock analysis and western blot analysis using STAT3 inhibitor, Pimozide. The treatment of transgenic (Flk-1+/egfr+) zebrafish embryos resulted in the STAT3 gene inhibition, proving its anti-angiogenic effect, as well. Thus, the study revealed that L72 could act as an antiproliferative agent, by triggering caspase-dependent intrinsic apoptosis, reducing cell proliferation by attenuating STAT3, and activating an anti-angiogenic pathway via Flk-1inhibition.

Synthesis, biological evaluation and molecular docking studies of novel 1,2,3-triazole-quinazolines as antiproliferative agents displaying ERK inhibitory activity

ERK1/2 inhibitors have attracted special attention concerning the ability of circumventing cases of innate or log-term acquired resistance to RAF and MEK kinase inhibitors. Based on the 4-aminoquinazoline pharmacophore of kinases, herein we describe the synthesis of 4-aminoquinazoline derivatives bearing a 1,2,3-triazole stable core to bridge different aromatic and heterocyclic rings using copper-catalysed azide-alkyne cycloaddition reaction (CuAAC) as a Click Chemistry strategy. The initial screening of twelve derivatives in tumoral cells (CAL-27, HN13, HGC-27, and BT-20) revealed that the most active in BT-20 cells (25a, IC₅₀ 24.6 μM and a SI of 3.25) contains a more polar side chain (sulfone). Furthermore, compound 25a promoted a significant release of lactate dehydrogenase (LDH), suggesting the induction of cell death by necrosis. In addition, this compound induced G0/G1 stalling in BT-20 cells, which was accompanied by a decrease in the S phase. Western blot analysis of the levels of p-STAT3, p-ERK, PARP, p53 and cleaved caspase-3 revealed p-ERK1/2 and p-STA3 were drastically decreased in BT-20 cells under 25a incubation, suggesting the involvement of these two kinases in the mechanisms underlying 25a-induced cell cycle arrest, besides loss of proliferation and viability of the breast cancer cell. Molecular docking simulations using the ERK-ulixertinib crystallographic complex showed compound 25a could potentially compete with ATP for binding to ERK in a slightly higher affinity than the reference ERK1/2 inhibitor. Further in silico analyses showed comparable toxicity and pharmacokinetic profiles for compound 25a in relation to ulixertinib.