Effect Of Cucurbitacin B Research Articles

Cucurbitacin B induces ferroptosis in oral leukoplakia via the SLC7A11/mitochondrial oxidative stress pathway

BackgroundOral leukoplakia (OLK), characterized by abnormal epithelial hyperplasia, is the most common precancerous oral mucosa lesion and is closely related to oxidative stress. Cucurbitacin B (CuB), a tetracyclic triterpenoid molecule derived from plants, has shown promising anti-proliferative and antioxidant effects in preclinical studies. However, whether CuB can play an antiproliferative role in OLK by regulating oxidative stress remains elusive. PurposeTo investigate the role of CuB in inhibiting the malignant progression of oral leukoplakia and to further explore its underlying mechanisms of action. MethodsIn vitro, the effect of CuB on the proliferation, migration, apoptosis, and cell cycle of OLK cells DOK was detected. The core genes and key pathways of OLK and CuB were analyzed in the transcriptome database, by using immunofluorescence, qRT-PCR, and Western blot to evaluate the expression levels of the ferroptosis markers ROS, GSH, MDA, Fe2+, and marker genes SLC7A11, GPX4, and FTH1. Immunohistochemistry of human tissue was performed to investigate the expression of the SLC7A11. In vivo, the model of OLK was established in C57BL/6 mice and the biosafety of CuB treatment for OLK was further evaluated. ResultsCuB substantially suppressed the proliferation of DOK cells. Bioinformatics analysis showed that the core targets of OLK crossing with CuB include SLC7A11 and that the essential pathways involve ROS and ferroptosis. In vitro experiments indicated that CuB might promote ferroptosis by down-regulating the expression of SLC7A11. We observed a gradual increase in SLC7A11 expression levels during the progression from normal oral mucosa to oral leukoplakia with varying degrees of epithelial dysplasia. In vivo experiments demonstrated that CuB inhibited the malignant progression of OLK by promoting ferroptosis in OLK mice and exhibited a certain level of biosafety. ConclusionThis study demonstrated for the first time that CuB could effectively inhibit the malignant progression of OLK by inducing ferroptosis via activating the SLC7A11/ mitochondrial oxidative stress pathway. These findings indicate that CuB could serve as the lead compound for the future development of anti-oral leukoplakia drugs.

Cucurbitacin B Regulates Immature Myeloid Cell Differentiation and Enhances Antitumor Immunity in Patients with Lung Cancer

The aberrant activation of the JAK2/STAT3 signaling in immature myeloid dendritic cells (DCs) is associated with immune tolerance and poor antitumor immunity. The objective of this study was to test the hypothesis that Cucurbitacin B (CuB), a selective inhibitor of JAK2/STAT3 signaling, could promote DC differentiation and improve antitumor immunity. Twelve patients with advanced lung cancers were treated orally with CuB daily for 7 consecutive days. The frequency of peripheral blood myeloid DCs and immature myeloid cells (imCs) in those patients and healthy controls was characterized longitudinally by flow cytometry. The effect of CuB on the differentiation of DCs and p53-specific T responses was evaluated in vitro. The percentages of Lin(-)DR(-)CD33(+) imCs and Lin(-)DR(+)CD33(+) DCs were significantly different between patients with lung cancers and healthy controls (1.55% vs. 0.82%, p=0.002; 0.60% vs. 1.90%, p=0.000). Treatment with CuB significantly increased the frequency of Lin(-)DR(+)CD33(+), but reduced the frequency of Lin(-)DR(-)CD33(+) in patients with lung cancers (p<0.05). Treatment with CuB induced the differentiation of DCs cocultured with tumor cells 16HBE/BPDE and enhanced the sensitivity of 16HBE/BPDE cells to p53-specific CTL by inhibiting the JAK2/STAT3 activation, but also enhancing the interferon-γ-related STAT1 activation in 16HBE/BPDE cells. CuB significantly reduced the frequency of imCs in patients with lung cancers and enhanced the effect of p53-specific CTL on tumor 16HBE/BPDE cells.