Ailanthone:a new potential drug for castration-resistant prostate cancer

Prostate cancer (PCa) is the most common male cancer [1, 2]. PCa initially depends on androgen receptor (AR) signaling for growth and survival. Androgen deprivation therapy causes a temporary reduction in PCa tumor burden, but the tumor eventually develops into castrationresistant prostate cancer (CRPC) with the ability to grow again in the absence of androgens [3]. Mechanisms of CRPC progression include AR amplification and overexpression [4], AR gene rearrangement promoting synthesis of constitutively-active truncated AR splice variants (ARVs) [4], and induction of intracrine androgen metabolic enzymes [3]. Current anti-androgen therapies including MDV3100 (Enzalutamide) and abiraterone have focused on the androgen-dependent activation of AR through its ligand-binding domain (LBD), but do not provide a continuing clinical benefit for patients with CRPC and presumably fail due to multiple mechanisms including the expression of AR-Vs lacking the LBD [5]. These AR-Vs signal in the absence of ligand and are therefore resistant to LBD-targeting AR antagonists or agents that repress androgen biosynthesis [6].

A novel synthetic small molecule YF-452 inhibits tumor growth through antiangiogenesis by suppressing VEGF receptor 2 signaling

Tumor angiogenesis is characterized by abnormal vessel morphology, endowing tumor with highly hypoxia and unresponsive toward treatment. To date, mounting angiogenic factors have been discovered as therapeutic targets in antiangiogenic drug development. Among them, vascular endothelial growth factor receptor 2 (VEGFR2) inhibitors exerts potent antiangiogenic activity in tumor therapy. Therefore, it may provide a valid strategy for cancer treatment through targeting the tumor angiogenesis via VEGFR2 pathway. In this study, we established a high-profile compounds library and certificated a novel compound named N-(N-pyrrolidylacetyl)-9-(4-bromobenzyl)-1,3,4,9-tetrahydro-β-carboline (YF-452), which remarkably inhibited the migration, invasion and tube-like structure formation of human umbilical vein endothelial cells (HUVECs) with little toxicity invitro. Rat thoracic aorta ring assay indicated that YF-452 significantly blocked the formation of microvascular exvivo. In addition, YF-452 inhibited angiogenesis in chick chorioallantoic membrane (CAM) and mouse corneal micropocket assays. Moreover, YF-452 remarkably suppressed tumor growth in xenografts mice model. Furthermore, investigation of molecular mechanism revealed that YF-452 inhibited VEGF-induced phosphorylation of VEGFR2 kinase and the downstream protein kinases including extracellular signal regulated kinase (ERK), focal adhesion kinase (FAK) and Src. These results indicate that YF-452 inhibits angiogenesis and may be a potential antiangiogenic drug candidate for cancer therapy.

Remodeling the immune microenvironment for gastric cancer therapy through antagonism of prostaglandin E2 receptor 4

Gastric cancer is highly prevalent among digestive tract tumors.Due to the intri-cate nature of the gastric cancer immune microenvironment,there is currently no effective treatment available for advanced gastric cancer.However,there is promising potential for immunotherapy targeting the prostaglandin E2 receptor subtype 4(EP4)in gastric cancer.In our previous study,we identified a novel small molecule EP4 receptor antagonist called YY001.Treatment with YY001 alone demonstrated a significant reduction in gastric cancer growth and inhibited tumor metastasis to the lungs in a mouse model.Furthermore,adminis-tration of YYo01 stimulated a robust immune response within the tumor microenvironment,characterized by increased infiltration of antigen-presenting cells,T cells,and M1 macro-phages.Additionally,our research revealed that YYo01 exhibited remarkable synergistic ef-fects when combined with the PD-1 antibody and the clinically targeted drug apatinib,rather than fluorouracil.These findings suggest that YYo01 holds great promise as a potential therapeutic strategy for gastric cancer,whether used as a standalone treatment or in combination with other drugs.