Bo Wang

Lysine-specific demethylase 1 (LSD1) is a validated cancer therapeutic target, critically implicated in maintaining cancer stem cells (CSCs) across leukemia and solid tumors. Although numerous potent LSD1 inhibitors have been developed, none have reached clinical approval, underscoring the need for novel agents with improved efficacy. Using a scaffold-hopping strategy, we designed and synthesized a novel class of phenoxazine-based LSD1 inhibitors. Among them, X-1 (IC₅₀ = 0.082 μM) emerged as the most potent, exhibiting a 3-fold improvement in activity over the previously reported compound 3s (IC₅₀ = 0.247 μM). Mechanistic studies revealed that X-1 suppressed the stemness of gastric cancer cells by interrupting the β-catenin-mediated transcriptional program, thereby reducing the expression of stemness-related proteins. In vivo studies confirmed its robust antitumor efficacy by inhibiting tumor proliferation and stemness without significant toxicity. Our findings identify X-1 as a promising LSD1-targeted inhibitor, offering a potential therapeutic strategy for gastric cancer.

Despite extensive efforts in drug development for cancer treatment, only a few successful therapeutic agents and strategies have emerged that specifically target patients with metastatic cancer, particularly those with distant metastasis. Cancer stem cells (CSCs), also known as cancer-initiating cells, represent a small population of cells within cancerous tissue that possess unlimited proliferative potential and the ability to drive tumor formation [1]. CSCs are believed to be the primary cause of drug resistance, cancer relapse, and metastasis, largely due to their capacities for self-renewal and differentiation.Importantly, CSCs can migrate to distant sites by promoting epithelial-to-mesenchymal transition (EMT), evading apoptosis, and escaping immune surveillance, all of which contribute to cancer metastasis and progression. As such, CSCs play a critical role in tumorigenesis, drug resistance, recurrence, and metastasis, highlighting the urgent need to develop targeted therapies to improve patient outcomes in oncology [2].Currently, advanced secondary cancers are typically only detected after multiple metastases have already occurred. The challenges associated with detecting dormant cancer cells or small metastases further complicate cancer treatment. Additionally, drugs targeting cancer metastasis often exhibit high cytotoxicity, inconsistencies in patient outcomes, and contribute to the development of drug resistance. Therefore, there is an urgent need for the development of novel small molecules, biological drugs, and combination therapies that target key processes in cancer metastasis.Several pathways, such as WNT/β-Catenin, Notch, PI3K/AKT, TGF-β, and PPAR, have been validated as key regulators of cancer metastasis. Effectively targeting these pathways offers promising opportunities for therapeutic interventions that could inhibit tumor growth and reduce cancer stemness [3]. This research aims to identify innovative small molecules and effective therapeutic strategies to target tumor metastasis and CSC-related processes, with the ultimate goal of improving survival rates for cancer patients.Metaplastic breast cancer (MpBC) is a collection of morphologically diverse and exceedingly aggressive variant disease, which can be classified as high or low grade based on the pathological features. As one type of high-grade MpBC, squamous cell carcinoma (SCC) cases usually possess negative expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), resembling triple-negative breast cancer (TNBC) but with a worse prognosis than conventional TNBC. Wang et al reported an initial rare case of a patient diagnosed with HER2-positive breast SCC, who achieved favorable outcomes by utilizing HER2targeted drugs in conjunction with chemotherapeutic drug paclitaxel. These findings suggest that HER2-targeted drugs can also exhibit positive effects on HER2-positive MpBC and SCC patients, thus providing a novel reference point for the subsequent treatment of uncommon pathological subtypes of breast cancer.Recently, immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. However, a significant proportion of gastric cancer (GC) patients do not benefit from this therapeutic strategy. To elucidate the mechanisms underlying GC patients resistance to ICIs and identify biomarkers able to predict the response to ICIs at treatment initiation stage, Sun et al collected GC tissues from 28 patients prior to the administration of anti-programmed death 1 (PD-1) immunotherapy and carried out protein quantification by high-resolution mass spectrometry (MS). Data analysis suggested that the low activity in the complement and coagulation cascades pathway and a high abundance of activated CD8+ T cells are positive signals corresponding to ICIs. They also identified 10 protein biomarkers with potential for predicting the response to PD-1 inhibitor immunotherapy in GC patients, which may provide the impetus for personalized precision immunotherapy.For anti-cancer drug development, 2D cell culture is the most commonly used method to evaluate tumor metastasis capability, but with limitations in representing cancer hallmarks and phenotypes. Ding et al reported an innovative approach which combines the advantages of 3D tumor spheroid culture with impedance-based biosensing technologies to establish a high-throughput 3D cell invasion assay for anti-metastasis drug screening through multicellular tumor spheroids. This method could be a promising tool for enhancing the quality of the drug development pipeline by providing a robust platform for predicting the efficacy and safety of anti-metastatic drugs before applying into preclinical or clinical trials.To improve the therapeutic efficacy and selectivity of chemotherapeutic agents for cancer treatment, the nanodrug delivery and targeting systems are initiated and thrivingly developed in recent years. However, most nanocarriers exhibit drawbacks including an intricate preparation process, limited drug-loading capacity, untargeted drug release, and nanocarrier toxicities. Wang et al took advantage of natural products with abundant scaffold diversity and structural complexity, and established two carrierfree berberine (BBR)-based nanoparticles (NPs) to increase their synergistic efficacy for tumor treatment. BBR interacts with glycyrrhetinic acid (GA) and artesunate (ART) to self-assemble BBR-GA and BBR-ART NPs, respectively, without any nanocarriers. These BBR-based NPs have been demonstrated to possess significant tumor targeting specificity and enhanced antitumor properties both in vitro and in vivo. These novel carrier-free self-assemblies based on natural products offer a strategy for synergistic drug delivery and thus shed lights on developing enhanced antitumor drugs.The stemness of CSCs plays a key role in driving hepatocellular carcinoma (HC) tumorigenesis, apoptotic resistance, and...

LSD1 (histone lysine-specific demethylase 1) has been gradually disclosed to act as an immunomodulator to enhance antitumor immune response. Despite the identification of numerous potent LSD1 inhibitors, there remains a lack of LSD1 inhibitors approved for marketing. Novel LSD1 inhibitors with different mechanisms are therefore needed. Herein, we reported a series of novel quinazoline-based LSD1 inhibitors. Among them, compound Z-1 exhibited the best LSD1 inhibitory activity (IC₅₀ = 0.108 μM). Z-1 also acted as a selective and cellular active as an LSD1 inhibitor. Furthermore, Z-1 promoted response of gastric cancer cells to T-cell killing effect by decreasing PD-L1 expression and further attenuated the PD-1/PD-L1 interaction. In vivo, Z-1 exhibited significant suppression effect on the growth of gastric cancer cells without obvious toxicity. Therefore, Z-1 represents a potential novel immunomodulator that targets LSD1, providing a lead compound with new function mechanism for gastric cancer treatment.

Given the malignancy of gastric cancer, developing highly effective and low‐toxic targeted drugs is essential to prolong patient survival and improve patient outcomes. In this study, we conducted structural optimizations based on the benzimidazole scaffold. Notably, compound 8 f presented the most potent antiproliferative activity in MGC803 cells and induced cell cycle arrest at the G0/G1 phase. Further mechanistic studies demonstrated that compound 8 f caused the apoptosis of MGC803 cells by elevating intracellular reactive oxygen species (ROS) levels and activating the mitogen‐activated protein kinase (MAPK) signaling pathway, accompanied by corresponding markers change. In vivo investigations additionally validated the inhibitory effect of compound 8 f on tumor growth in xenograft models bearing MGC803 cells without obvious toxicity. Our studies suggest that compound 8 f holds promise as a potential and safe lead compound for developing anti‐gastric cancer agents.