Acetyl-cinobufagin suppresses triple-negative breast cancer progression by inhibiting the STAT3 pathway

Anticancer potential of osthole: targeting gynecological tumors and breast cancer

Gynecological tumors, such as ovarian, endometrial, and cervical cancers, alongside breast cancer, represent significant malignancies that pose serious threats to women's health worldwide. Standard treatments, including surgery, chemotherapy, radiotherapy, and targeted therapies, are commonly utilized in clinical practice. However, challenges such as high recurrence rates, drug resistance, and adverse side effects underscore the urgent need for more effective therapeutic options. Osthole, a natural coumarin compound derived from Chinese herbal medicine, has demonstrated remarkable antitumor activity against various cancers. Emerging evidence indicates that osthole can inhibit the proliferation, invasion, and metastasis of gynecological and breast cancer cells through various mechanisms, including inducing apoptosis and autophagy, regulating the tumor microenvironment, inhibiting tumor angiogenesis, and enhancing the sensitivity of cancer cells to chemotherapy and radiotherapy. This review highlights the recent advancements in osthole research within the context of gynecological and breast cancers, focusing on its molecular mechanisms, and offers a theoretical foundation for its potential development as an anticancer agent.

PCSK5 downregulation promotes the inhibitory effect of andrographolide on glioblastoma through regulating STAT3

Proprotein convertase subtilisin/kexin type 5 (PCSK5) is a member of the proprotein convertase (PC) family, which processes immature proteins into functional proteins and plays an important role in the process of cell migration and transformation. Andrographolide is a non-peptide compound with PC inhibition and antitumor activity. Our research aimed to investigate the functional role of PCSK5 downregulation combined with Andro on GBM progression. Results from the cancer genome atlas (TCGA) and clinical samples revealed a significant upregulation of PCSK5 in GBM tissues than in non-tumor brain tissues. Higher expression of PCSK5 was correlated with advanced GBM stages and worse patient prognosis. PCSK5 knockdown attenuated the epithelial-mesenchymal transition (EMT)-like properties of GBM cells induced by IL-6. PCSK5 knockdown in combination with Andro treatment significantly inhibited the proliferation and invasion of GBM cells in vitro, as well as tumor growth in vivo. Mechanistically, PCSK5 downregulation reduced the expression of p-STAT3 and Matrix metalloproteinases (MMPs), which could be rescued by the p-STAT3 agonist. STAT3 silencing downregulated the expression of MMPs without affecting PCSK5. Furthermore, Andro in combination with PCSK5 silencing significantly inhibited STAT3/MMPs axis. These observations provided evidence that PCSK5 functioned as a potential tumor promoter by regulating p-STAT3/MMPs and the combination of Andro with PCSK5 silencing might be a good strategy to prevent GBM progression.

Fantastic Frogs and Where to Use Them: Unveiling the Hidden Cinobufagin's Promise in Combating Lung Cancer Development and Progression Through a Systematic Review of Preclinical Evidence

Cinobufagin (CB), a bufadienolide, has shown promising potential as an anticancer agent, particularly in combating lung cancer. This systematic review synthesizes preclinical evidence on CB's effects against lung cancer, focusing on its mechanisms of action, efficacy, and potential clinical implications. We analyzed data from various preclinical studies involving both in vitro cell line models and in vivo animal models. The reviewed studies indicate that CB effectively reduces cell viability, induces apoptosis, and inhibits cell proliferation, migration, and invasion across multiple lung cancer cell lines and xenograft models. Specifically, CB was found to decrease cell viability and increase apoptosis in lung cancer cells by modulating key molecular pathways, including Bcl-2, Bax, cleaved caspases, caveolin-1, FLOT2, Akt, STAT3, and FOXO1. In vivo studies further demonstrated significant inhibition of tumor growth with minimal toxicity. However, limitations include reliance on in vitro models, which may not fully represent in vivo tumor dynamics, and a lack of long-term safety data. The studies also vary in their methodologies and cell line models, which may not accurately encompass all lung cancer subtypes or predict human responses. Despite these limitations, CB's ability to target specific molecular pathways and its promising results in preclinical models suggest it could be a valuable addition to lung cancer treatment strategies. Our review suggests further clinical trials to validate its efficacy and safety in humans. Future research should explore combination therapies and optimize delivery methods to enhance clinical outcomes.

Obesity and lack of breastfeeding: a perfect storm to augment risk of breast cancer?

Triple-negative breast cancer (TNBC) is one of the most aggressive subtypes of breast cancer with higher rates of recurrence and distant metastasis, as well as decreased 5-year survival rates. Racial disparities are evident in the incidence and mortality rates of triple negative breast cancer particularly increased in young African American women. Concurrently, young African American women have multiple risk factors for TNBC including higher rates of premenopausal abdominal obesity (higher waist-hip ratio) and lower rates of breastfeeding with higher parity, implicating these factors as potentially contributors to poor outcomes. By understanding the mechanisms of how premenopausal obesity and lack of breastfeeding may be associated with increased risk of triple negative breast cancer, we can determine the best strategies for intervention and awareness to improve outcomes in TNBC.

Inhibitory Impact Of Cinobufagin In Triple-Negative Breast Cancer Metastasis: Involvements Of Macrophage Reprogramming Through Upregulated MME and Inactivated FAK/STAT3 Signaling

BACKGROUND

Cinobufagin (CBG), a key bioactive component in cinobufacini, exhibits antitumor properties. This study explores CBG's impact on triple-negative breast cancer (TNBC) metastasis and elucidates the underpinning mechanism.

METHODS

Murine xenograft and orthotopic metastatic TNBC models were generated and treated with CBG. The burden of metastatic tumor in the mouse lung, the epithelial to mesenchymal transition (EMT) markers, and macrophage polarization markers within the tumors were examined. The phenotype of tumor-associated macrophages (TAMs) and mobility of TNBCs in vitro in a macrophage-TNBC cell coculture system were analyzed. Physiological targets of CBG were identified by bioinformatics analyses.

RESULTS

CBG treatment significantly alleviated lung tumor burden and EMT activity. It triggered an M2-to-M1 shift in TAMs, resulting in decreased TNBC cell migration, invasion, and EMT in vitro. CBG upregulated membrane metalloendopeptidase (MME) expression, suppressing FAK and STAT3 phosphorylation. Silencing of MME, either in mice or TAMs, counteracted CBG effects, reinstating M2 TAM predominance and enhancing TNBC cell metastasis. Cotreatment with Defactinib, a FAK antagonist, reversed M2 TAM polarization and TNBC cell metastasis. Notably, MME silencing in TNBC cells had no impact on CBG-suppressed malignant properties, indicating MME's indirect involvement in TNBC cell behavior through TAM mediation.

CONCLUSION

This study unveils CBG's ability to enhance MME expression, deactivate FAK/STAT3 signaling, and inhibit TNBC metastasis by suppressing M2-skewed macrophages.

Potential therapeutic targets of the JAK2/STAT3 signaling pathway in triple-negative breast cancer

Triple-negative breast cancer (TNBC) poses a significant clinical challenge due to its propensity for metastasis and poor prognosis. TNBC evades the body's immune system recognition and attack through various mechanisms, including the Janus Kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. This pathway, characterized by heightened activity in numerous solid tumors, exhibits pronounced activation in specific TNBC subtypes. Consequently, targeting the JAK2/STAT3 signaling pathway emerges as a promising and precise therapeutic strategy for TNBC. The signal transduction cascade of the JAK2/STAT3 pathway predominantly involves receptor tyrosine kinases, the tyrosine kinase JAK2, and the transcription factor STAT3. Ongoing preclinical studies and clinical research are actively investigating this pathway as a potential therapeutic target for TNBC treatment. This article comprehensively reviews preclinical and clinical investigations into TNBC treatment by targeting the JAK2/STAT3 signaling pathway using small molecule compounds. The review explores the role of the JAK2/STAT3 pathway in TNBC therapeutics, evaluating the benefits and limitations of active inhibitors and proteolysis-targeting chimeras in TNBC treatment. The aim is to facilitate the development of novel small-molecule compounds that target TNBC effectively. Ultimately, this work seeks to contribute to enhancing therapeutic efficacy for patients with TNBC.