Demethylzeylasteral exerts potent efficacy against non-small-cell lung cancer via the P53 signaling pathway.

Lung cancer has one of the highest mortality rates worldwide, with non-small-cell lung cancer (NSCLC) constituting approximately 85% of all cases. Demethylzeylasteral (DEM), extracted from Tripterygium wilfordii Hook F, exhibits notable anti-tumor properties. In this study, we revealed that DEM could effectively induce NSCLC cell apoptosis. Specifically, DEM can dose-dependently suppress the viability and migration of human NSCLC cells. RNA-seq analysis revealed that DEM regulates the P53-signaling pathway, which was further validated by assessing crucial proteins involved in this pathway. Biacore analysis indicated that DEM has high affinity with the P53 protein. The CDX model demonstrated DEM's anti-tumor actions. This work provided evidence that DEM-P53 interaction stabilizes P53 protein and triggers downstream anti-tumor activities. These findings indicate that DEM treatment holds promise as a potential therapeutic approach for NSCLC, which warrants further clinical assessment in patients with NSCLC.

Pan-cancer analysis of NUP155 and validation of its role in breast cancer cell proliferation, migration, and apoptosis.

NUP155 is reported to be correlated with tumor development. However, the role of NUP155 in tumor physiology and the tumor immune microenvironment (TIME) has not been previously examined. This study comprehensively investigated the expression, immunological function, and prognostic significance of NUP155 in different cancer types. Bioinformatics analysis revealed that NUP155 was upregulated in 26 types of cancer. Additionally, NUP155 upregulation was strongly correlated with advanced pathological or clinical stages and poor prognosis in several cancers. Furthermore, NUP155 was significantly and positively correlated with DNA methylation, tumor mutational burden, microsatellite instability, and stemness score in most cancers. Additionally, NUP155 was also found to be involved in TIME and closely associated with tumor infiltrating immune cells and immunoregulation-related genes. Functional enrichment analysis revealed a strong correlation between NUP155 and immunomodulatory pathways, especially antigen processing and presentation. The role of NUP155 in breast cancer has not been examined. This study, for the first time, demonstrated that NUP155 was upregulated in breast invasive carcinoma (BRCA) cells and revealed its oncogenic role in BRCA using molecular biology experiments. Thus, our study highlights the potential value of NUP155 as a biomarker in the assessment of prognostic prediction, tumor microenvironment and immunotherapeutic response in pan-cancer.

Prognostic value analysis of cholesterol and cholesterol homeostasis related genes in breast cancer by Mendelian randomization and multi-omics machine learning.

Introduction: The high incidence of breast cancer (BC) prompted us to explore more factors that might affect its occurrence, development, treatment, and also recurrence. Dysregulation of cholesterol metabolism has been widely observed in BC; however, the detailed role of how cholesterol metabolism affects chemo-sensitivity, and immune response, as well as the clinical outcome of BC is unknown. Methods: With Mendelian randomization (MR) analysis, the potential causal relationship between genetic variants of cholesterol and BC risk was assessed first. Then we analyzed 73 cholesterol homeostasis-related genes (CHGs) in BC samples and their expression patterns in the TCGA cohort with consensus clustering analysis, aiming to figure out the relationship between cholesterol homeostasis and BC prognosis. Based on the CHG analysis, we established a CAG_score used for predicting therapeutic response and overall survival (OS) of BC patients. Furthermore, a machine learning method was adopted to accurately predict the prognosis of BC patients by comparing multi-omics differences of different risk groups. Results: We observed that the alterations in plasma cholesterol appear to be correlative with the venture of BC (MR Egger, OR: 0.54, 95% CI: 0.35-0.84, p<0.006). The expression patterns of CHGs were classified into two distinct groups(C1 and C2). Notably, the C1 group exhibited a favorable prognosis characterized by a suppressed immune response and enhanced cholesterol metabolism in comparison to the C2 group. In addition, high CHG score were accompanied by high performance of tumor angiogenesis genes. Interestingly, the expression of vascular genes (CDH5, CLDN5, TIE1, JAM2, TEK) is lower in patients with high expression of CHGs, which means that these patients have poorer vascular stability. The CAG_score exhibits robust predictive capability for the immune microenvironment characteristics and prognosis of patients(AUC=0.79). It can also optimize the administration of various first-line drugs, including AKT inhibitors VIII Imatinib, Crizotinib, Saracatinib, Erlotinib, Dasatinib, Rapamycin, Roscovitine and Shikonin in BC patients. Finally, we employed machine learning techniques to construct a multi-omics prediction model(Risklight),with an area under the feature curve (AUC) of up to 0.89. Conclusion: With the help of CAG_score and Risklight, we reveal the signature of cholesterol homeostasis-related genes for angiogenesis, immune responses, and the therapeutic response in breast cancer, which contributes to precision medicine and improved prognosis of BC.

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

BACKGROUND: The incidence of breast cancer (BC) worldwide has increased substantially in recent years. Epithelial-mesenchymal transition (EMT) refers to a crucial event impacting tumor heterogeneity. Although cinobufagin acts as an effective anticancer agent, the clinical use of cinobufagin is limited due to its strong toxicity. Acetyl-cinobufagin, a pre-drug of cinobufagin, was developed and prepared with greater efficacy and lower toxicity. METHODS: A heterograft mouse model using triple negative breast cancer (TNBC) cell lines, was used to evaluate the potency of acetyl-cinobufagin. Signal transducer and stimulator of transcription 3 (STAT3)/EMT involvement was investigated by gene knockout experiments using siRNA and Western blot analysis. RESULTS: Acetyl-cinobufagin inhibited proliferation, migration, and cell cycle S/G2 transition and promoted apoptosis in TNBC cells in vitro. In general, IL6 triggered the phosphorylation of the transcription factor STAT3 thereby activating the STAT3 pathway and inducing EMT. Mechanistically, acetyl-cinobufagin suppressed the phosphorylation of the transcription factor STAT3 and blocked the interleukin (IL6)-triggered translocation of STAT3 to the cell nucleus. In addition, acetyl-cinobufagin suppressed EMT in TNBC by inhibiting the STAT3 pathway. Experiments in an animal model of breast cancer clearly showed that acetyl-cinobufagin was able to reduce tumor growth. CONCLUSIONS: The findings of this study support the potential clinical use of acetyl-cinobufagin as a STAT3 inhibitor in TNBC adjuvant therapy.

ß, ß-Dimethylacrylshikonin potentiates paclitaxel activity, suppresses immune evasion and triple negative breast cancer progression via STAT3Y705 phosphorylation inhibition based on network pharmacology and transcriptomics analysis.

BACKGOUND: Triple negative breast cancer (TNBC) is an extremely aggressive and rapidly progressing cancer, wherein existing therapies provide little benefit to patients. ß, ß-Dimethylacrylshikonin (DMAS), an active naphthoquinone derived from comfrey root, has potent anticancer activity. However, the antitumor function of DMAS against TNBC remains to be proved. PURPOSE: Explore effects of DMAS on TNBC and clarify the mechanism. STUDY DESIGN: Network pharmacology, transcriptomics and various cell functional experiments were applied to TNBC cells to explore the effects of DMAS on TNBC. The conclusions were further validated in xenograft animal models. METHODS: MTT, EdU, transwell, scratch tests, flow cytometry, immunofluorescence, and immunoblot were utilized to assess the activity of DMAS on three TNBC cell lines. The anti-TNBC mechanism of DMAS was clarified by overexpression and knockdown of STAT3 in BT-549 cells. In vivo efficacy of DMAS was analysed using a xenograft mouse model. RESULTS: In vitro analysis revealed that DMAS inhibited the G2/M phase transition and suppressed TNBC proliferation. Additionally, DMAS triggered mitochondrial-dependent apoptosis and reduced cell migration by antagonizing epithelial-mesenchymal transition. Mechanistically, DMAS exerted its antitumour effects by inhibiting STAT3Y705 phosphorylation. STAT3 overexpression abolished the inhibitory effect of DMAS. Further studies showed that treatment with DMAS inhibited TNBC growth in a xenograft model. Notably, DMAS potentiated the sensitivity of TNBC to paclitaxel and inhibited immune evasion by downregulating the immune checkpoint PD-L1. CONCLUSIONS: For the first time, our study revealed that DMAS potentiates paclitaxel activity, suppresses immune evasion and TNBC progression by inhibiting STAT3 pathway. It has the potential as a promising agent for TNBC.

A Novel Approach: Combining Prognostic Models and Network Pharmacology to Target Breast Cancer Necroptosis-Associated Genes.

Breast cancer (BC) accounts for the highest proportion of the all cancers among women, and necroptosis is recognized as a form of caspase-independent programmed cell death. We created prognostic signatures using univariate survival analysis, and lasso regression, to assess immune microenvironments between subgroups. We then used network pharmacology to bind our drugs to target differentially expressed genes (DEGs). A signature comprising a set of necroptosis-related genes was established to predict patient outcomes based on median risk scores. Those above and below the median were classified as high-risk group (HRG) and low-risk group (LRG), respectively. Patients at high risk had lower overall survival, and poorer predicted tumor, nodes, and metastases stages (TNM). The novel prognostic signature can effectively predict the prognosis of breast cancer patients docking of ß,ß-dimethyl acryloyl shikonin (DMAS) to possible targets to cure breast cancer. We found that all current prognostic models do not offer suitable treatment options. In additional, by docking drugs DMAS that have been initially validated in our laboratory to treat breast cancer. We hope that this novel approach could contribute to cancer research.

Downstream Neighbor of Son Overexpression is Associated With Breast Cancer Progression and a Poor Prognosis.

PURPOSE: The incidence rate of breast cancer (BC) has increased annually. Downstream neighbor of son (DONSON) critically affects cell cycle progression and maintains stable genomic properties; however, its relevant effects on BC growth and progression require in-depth investigation. METHODS: DONSON upregulation was validated in public databases. DONSON expression in matched BC and adjacent tissues and cell lines (MDA-MB-231, BT-549, and HS-578T) was determined using quantitative reverse transcription polymerase chain reaction. In vitro apoptosis, invasion, migration, and proliferation tests were performed to ascertain the functions of DONSON in BC cell lines. Then, using western blot analysis, the levels of DONSON downstream proteins were determined. RESULTS: Compared to the control, DONSON was expressed at higher levels in BC tissues and cell lines. DONSON knockdown facilitated apoptosis and limited proliferation, migration, invasion, and S/G2 transition of BC cells in vitro. Furthermore, DONSON overexpression promoted BC cell proliferation and inhibited apoptosis in vitro. Moreover, DONSON knockdown reduced cyclin A1 and cyclin-dependent kinase 2 levels. Moreover, DONSON knockdown limited the progression of epithelial-mesenchymal transition. CONCLUSION: DONSON critically affects BC growth and serves as a possible target and marker for the efficacy of subsequent therapies.

A Novel Nomogram Model to Identify Candidates and Predict the Possibility of Benefit From Primary Tumor Resection Among Female Patients With Metastatic Infiltrating Duct Carcinoma of the Breast: A Large Cohort Study.

BACKGROUND: The impact of primary site surgery on survival remains controversial in female patients with stage IV breast cancer. The purpose of this study was to investigate the role of primary tumor surgery in patients with stage IV breast cancer and concurrently develop a nomogram to identify which patients will benefit from surgery. METHODS: We retrospectively searched the SEER database for female patients newly diagnosed with stage IV breast infiltrating duct carcinoma (BIDC) between 2010 and 2015 and then divided them into surgery and non-surgery groups. The propensity score matching (PSM) method was implemented to eliminate the bias, and Kaplan-Meier survival analysis was generated to compare the overall survival (OS) and cancer-specific survival (CSS) between the two groups. After PSM, Cox regression analyses were performed to determine the independent protective value of primary tumor surgery, while logistic regression analyses were utilized to uncover significant predictors of surgical benefit and establish a screening nomogram for female patients with stage IV BIDC. Nomogram performance was evaluated by calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA). RESULT: 5,475 patients with stage IV BIDC were included in this study, and 2,375 patients (43.38%) received primary tumor surgery. After PSM, the median CSS was 53 months (95% CI: 46.84-59.16) in the surgery group compared with only 33 months (95% CI: 30.05-35.95) in the non-surgery group. We further found that primary tumor surgery was an independent protective factor for patients with stage IV BIDC. The independent factors affecting the benefit of locoregional surgery in patients with stage IV BIDC included histological grade, T stage, molecular subtype, lung metastasis, liver metastasis, brain metastasis, and marital status. The AUC of the nomogram was 0.785 in the training set and 0.761 in the testing set. The calibration curves and DCA confirmed that the nomogram could precisely predict the possibility of benefit from primary tumor resection. CONCLUSION: Our study suggested that primary tumor surgery improved the prognosis of female patients with stage IV BIDC and developed a nomogram to quantify the probability of surgical benefit to help identify surgical candidates clinically.

Genetic landscape of breast cancer and mutation tracking with circulating tumor DNA in Chinese women.

Considerable efforts have been devoted to exploring the breast cancer mutational landscape to understand its genetic complexity. However, no studies have yet comprehensively elucidated the molecular characterization of breast tumors in Chinese women. This study aimed to determine the potential clinical utility of peripheral blood assessment for circulating tumor-derived DNA (ctDNA) and comprehensively characterize the female Chinese population's genetic mutational spectrum. We used Omi-Seq to create cancer profiles of 273 patients enrolled at The First Affiliated Hospital of Wenzhou Medical University. The gene landscape results indicate PIK3CA and TP53 as the most frequently detected genes, followed by ERBB2, in Chinese breast cancer patients. The accuracy of ERBB2 copy number variations in tissue/formalin-fixed and paraffin-embedded samples was 95% with 86% sensitivity and 99% specificity. Moreover, mutation numbers varied between different molecular cell-free DNA subtypes, with the basal-like patients harboring a higher number of variants than the luminal patients. Furthermore, ratio changes in the max ctDNA allele fraction highly correlated with clinical response measurements, including cancer relapse and metastasis. Our data demonstrate that ctDNA characterization using the Omi-Seq platform can extend the capacity of personalized clinical cancer management.

Cinobufagin suppresses colorectal cancer growth via STAT3 pathway inhibition.

Colorectal cancer (CRC) has become one of the most common types of cancer with the highest morbidity and mortality rates globally. Cinobufagin, a natural product extracted from toad venom and a major active ingredient in cinobufotalin, exhibits high antitumor activity. Here, we investigated the in vitro and in vivo antitumor activities of cinobufagin and explored the underlying mechanisms in CRC. Cinobufagin could inhibit proliferation, migration, invasion and promote apoptosis of HCT116, RKO, and SW480 cells in vitro. Mechanistically, cinobufagin simultaneously suppressed the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and blocked the interleukin-6 (IL6)-induced nuclear translocation of STAT3. IL6 activated the STAT3 pathway, subsequently inducing epithelial-mesenchymal transition (EMT). Furthermore, cinobufagin suppressed EMT in CRC by inhibiting the STAT3 pathway. Animal experiments clearly showed that cinobufagin could reduce tumor growth. Cinobufagin may be used clinically as a novel STAT3 inhibitor for CRC adjuvant therapy.

Acetyl-bufalin shows potent efficacy against non-small-cell lung cancer by targeting the CDK9/STAT3 signalling pathway.

BACKGROUND: Cyclin-dependent kinase 9 (CDK9) is a promising prognostic marker and therapeutic target in cancers. Bufalin is an effective anti-tumour agent; however, the clinical application of bufalin is limited due to its high toxicity. Acetyl-bufalin, the bufalin prodrug, was designed and synthesised with higher efficiency and lower toxicity. METHODS: Three non-small-cell lung cancer (NSCLC) cell lines, a xenograft model and a patient-derived xenograft (PDX) model were used to examine the effects of acetyl-bufalin. CDK9/STAT3 involvement was investigated by knockdown with siRNA, proteome microarray assay, western blot analysis and co-immunoprecipitation experiments. Acute toxicity test and pharmacokinetics (PK) study were conducted to assess the safety and PK. The human NSCLC tissues were analysed to verify high CDK9 expression. RESULTS: We showed that CDK9 induced NSCLC cell proliferation and that this effect was associated with STAT3 activation, specifically an increase in STAT3 phosphorylation and transcription factor activity. Acetyl-bufalin is an effective and safety inhibitor of the CDK9/STAT3 pathway, leading to the impediment of various oncogenic processes in NSCLC. Molecular docking and high-throughput proteomics platform analysis uncovered acetyl-bufalin directly binds to CDK9. Consequently, acetyl-bufalin impaired the complex formation of CDK9 and STAT3, decreased the expressions of P-STAT3, and transcribed target genes such as cyclin B1, CDC2, MCL-1, Survivin, VEGF, BCL2, and it upregulated the expression levels of BAX and caspase-3 activity. Acetyl-bufalin inhibited tumour growth in NSCLC xenograft and PDX models. CONCLUSIONS: Acetyl-bufalin is a novel blocker of the CDK9/STAT3 pathway thus may have potential in therapy of NSCLC and other cancers.

The Prognostic Value of Combination of Plasma Fibrinogen and CA19-9 in Non-Distant Metastatic Breast Cancer Patients Undergoing Surgery.

PURPOSE: This article aimed to study the prognostic value of preoperative plasma fibrinogen and CA19-9 in non-distant metastatic breast cancer (BC). PATIENTS AND METHODS: A total of 343 non-distant metastatic BC patients were included in this study. The optimal cut-off values of plasma fibrinogen and CA19-9 were obtained by receiver operating characteristic (ROC) curve analysis. Univariate and multivariate Cox regression analyses were used to evaluate prognostic factors for overall survival (OS). Survival data were assessed using Kaplan-Meier survival analysis with the Log-rank test. Based on the cut-off values, we classified the fibrinogen-CA19-9 score as follows: 2 (both hyperfibrinogenemia and high CA19-9), 1 (either hyperfibrinogenemia or high CA19-9), and 0 (neither hypefibrinogenemia nor high CA19-9). RESULTS: Our follow-up time totaled 10 years, the median follow-up time was 77 months (range=2-119 months), and 82 (23.9%) of 343 patients died during the follow-up period. The optimal cut-off values of plasma fibrinogen and CA19-9 were 2.805 g/L and 11.85 U/mL, respectively. The multivariate Cox analysis results suggested that there was a significant association between worse OS and elevated preoperative plasma fibrinogen and CA19-9 levels (HR=2.016, 95% CI=1.216-3.342, P=0.007; and HR=2.042, 95% CI=1.282-3.253, P=0.003). The area under the ROC curve (AUC) increased from 0.589 (for plasma fibrinogen) and 0.594 (for CA19-9) to 0.640 when these two parameters were combined. When we added this combined factor to the multivariate analysis, it was an independent prognostic factor for BC (P<0.001). According to the above results, we chose four prognostic factors to construct our nomogram. The AUC was 0.724, which indicates that the nomogram performs well. CONCLUSION: The combination of plasma fibrinogen and CA19-9 could be used as a valid independent prognostic factor for non-distant metastatic BC compared with either parameter alone and could easily be applied in clinical practice.

Cynaropicrin Shows Antitumor Progression Potential in Colorectal Cancer Through Mediation of the LIFR/STATs Axis.

BACKGROUND: Colorectal cancer (CRC) is the second deadliest malignant disease in the world and the leukemia inhibitory factor receptor/signal transducers and activators of transcriptions (LIFR/STATs) signaling axis plays an important role in the molecular biology of CRC. METHODS: Cell function tests were performed to observe the inhibitory effect of cynaropicrin on human CRC cells (RKO, HCT116, and DLD-1). Expression levels of LIFR, P-STAT3, P-STAT4, and apoptotic proteins were detected by Western blotting. Immunoprecipitation confirmed the presence of LIFR/STAT3/STAT4 complex. Cell immunofluorescence assay was used to observe the subcellular localization of STAT3 and STAT4. In vivo efficacy of cynaropicrin was evaluated by a xenotransplantation model in nude mice. RESULTS: Cynaropicrin significantly reduced the survival ability of human CRC cells and promoted apoptosis in a dose-dependent manner. Western blotting results suggested that the antitumor effects of cynaropicrin might be mediated by inhibition of the LIFR/STATs axis. Cynaropicrin reduced the formation of STAT3/STAT4 heterodimers and blocked their entry into the nucleus. Cynaropicrin also suppressed tumor growth in the xenograft model. CONCLUSION: The results showed that cynaropicrin exerted a strong inhibitory effect on CRC in vitro and in vivo. Our study concluded that cynaropicrin has potential application prospects in the field of anti-CRC therapy.

Rhein shows potent efficacy against non-small-cell lung cancer through inhibiting the STAT3 pathway.

BACKGROUND: Non-small-cell lung cancer (NSCLC) comprises about 85% of all lung cancers and is usually diagnosed at an advanced stage with poor prognosis. The IL-6/STAT3 signaling pathway plays a pivotal role in NSCLC biology. Rhein is a lipophilic anthraquinone extensively found in medicinal herbs. Emerging evidence suggests that Rhein has significant antitumor effects, supporting the potential uses of Rhein as an antitumor agent. METHODS: Cell viability and colony formation were performed to examine Rhein's potent anti-proliferative effect in human NSCLC cell lines PC-9, H460 and A549. Flow cytometry-based assay was employed to study whether Rhein could affect cell apoptosis and cycle. The expression level of P-STAT3, apoptosis and cycle-related proteins Bcl-2, Bax, MDM2, CDC2, P53 and CyclinB1 were detected by Western blotting. The xenograft models were used to evaluate the in vivo effect of Rhein. RESULTS: We found that Rhein could significantly reduce the viability and stimulate apoptosis in human NSCLC cells in a dose-dependent manner. Western blot analysis results suggested that the antitumor effect of Rhein might be mediated via STAT3 inhibition. Rhein upregulated the expression of the proapoptotic protein Bax and downregulated the expression of the antiapoptotic protein Bcl-2. In addition, Rhein induced the arrest of NSCLC cells in the G2/M phase of the cell cycle and dose dependently inhibited the expression of cycle-related proteins. The Rhein also inhibited tumor growth in H460 xenograft models. CONCLUSION: Rhein shows potent efficacy against NSCLC through inhibiting the STAT3 pathway. Our results also suggest that Rhein has a promising potential to be used as a novel antitumor agent for the treatment of NSCLC.

Rhein sensitizes human pancreatic cancer cells to EGFR inhibitors by inhibiting STAT3 pathway.

BACKGROUND: Rhein is a lipophilic anthraquinone extensively found in medicinal herbs. Emerging evidence suggests that rhein has significant antitumor effects, supporting its potential use as an antitumor agent. The IL6/STAT3 signaling pathway has been suggested as an attractive target for the discovery of novel cancer therapeutics. METHODS: The human pancreatic cancer cell lines AsPC-1, Patu8988T, BxPC-3 and PANC-1, and immunodeficient mice were chosen as models to study the effects of rhein. The potent antiproliferative and proapoptotic effects of rhein were examined by cell viability, cellular morphology, apoptosis and colony formation assays. The STAT3 luciferase report assay, immunostaining analysis and Western blot analysis revealed the inhibition of the IL6/STAT3 signaling axis. RESULTS: Apoptosis was induced by adjunctive use of rhein with epidermal growth factor receptor (EGFR) inhibitors in pancreatic cancer cells as verified by cell apoptosis analysis and changes in the expression level of apoptotic/anti-apoptotic proteins BCL-2, BAX, Caspase 3 and Cl-PARP. Suppression of the phosphorylation of STAT3 and EGFR were also observed as a result of the treatment with a combination of rhein and EGFR inhibitors. Most interestingly, it was found that rhein considerably sensitized cells to erlotinib, thus suppressing tumor growth in PANC-1 and BxPC-3 xenograft models. The in vivo anti-tumor effect was associated with increased apoptosis and combined inhibition of the STAT3 and EGFR pathways in tumor remnants. CONCLUSIONS: Rhein sensitizes human pancreatic cancer cells to EGFR inhibitors through inhibition of STAT3. Taken together, the results indicate that rhein offers a novel blueprint for pancreatic cancer therapy, particularly when combined with EGFR inhibitors.

Alantolactone promotes ER stress-mediated apoptosis by inhibition of TrxR1 in triple-negative breast cancer cell lines and in a mouse model.

Triple-negative breast cancer (TNBC) is a subtype of breast cancer with poor clinical outcome and currently no effective targeted therapies are available. Alantolactone (ATL), a sesquiterpene lactone, has been shown to have potential anti-tumour activity against various cancer cells. However, the underlying mechanism and therapeutic effect of ATL in the TNBC are largely unknown. In the present study, we found that ATL suppresses TNBC cell viability by reactive oxygen species (ROS) accumulation and subsequent ROS-dependent endoplasmic reticulum (ER) stress both in vitro and in vivo. Thioredoxin reductase 1 (TrxR1) expression and activity of were significantly up-regulated in the TNBC tissue specimens compare to the normal adjacent tissues. Further analyses showed that ATL inhibits the activity of TrxR1 both in vitro and in vivo in TNBC and knockdown of TrxR1 in TNBC cells sensitized ATL-induced cell apoptosis and ROS increase. These results will provide pre-clinical evidences that ATL could be a potential therapeutic agent against TNBC by promoting ROS-ER stress-mediated apoptosis through partly targeting TrxR1.

Alantolactone sensitizes human pancreatic cancer cells to EGFR inhibitors through the inhibition of STAT3 signaling.

Several studies have implicated the feedback activation of signal transducer and activator of transcription 3 (STAT3) as a new cancer drug-resistance mechanism and linked it to the failure of epidermal growth factor receptor (EGFR)-targeted therapies. In this study, we discovered that Alantolactone, a natural sesquiterpene lactone, potently inhibited human pancreatic cancer cells and suppressed constitutively activated STAT3. In contrast, Alantolactone had little effect on the EGFR pathway. Moreover, combination of Alantolactone and an EGFR inhibitor, Erlotinib or Afatinib, demonstrated a remarkable synergistic anti-cancer effect against pancreatic cancer cells both in vitro and in vivo. Our results suggested that Alantolactone could sensitize human pancreatic cancer cells to EGFR inhibitors possibly through down-regulating the STAT3 signaling. Alantolactone, when combined with other EGFR targeted agents, could be further developed as a potential therapy for pancreatic cancer.

Osthole inhibits triple negative breast cancer cells by suppressing STAT3.

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive subgroup of human breast cancer. Patients with TNBC have poor clinical outcome as they are non-responsive to current targeted therapies. There is an urgent need to identify new therapeutic targets and develop more effective treatment options for TNBC patients. Osthole, a natural product from C. monnieri, has been shown to inhibit certain cancer cells. However, the mechanisms of action as well as its effect on TNBC cells are not currently known. METHODS: We investigated the effect of osthole in cultured TNBC cells as well as in a xenograft model of TNBC growth. We also used a high-throughput proteomics platform to identify the direct binding protein of osthole. RESULTS: We found that osthole inhibited the growth of a panel of TNBC cells and induced apoptosis in both cultured cells and TNBC xenografts. We used a high-throughput proteomics platform and identified signal transducer and activator of transcription 3 (STAT3) as a potential binding protein of osthole. We further show that osthole suppressed STAT3 in TNBC cells to inhibit growth and induce apoptosis. Overexpressing STAT3 in TNBC reduced the effectiveness of osthole treatment. CONCLUSIONS: These results provide support for osthole as a potential new therapeutic agent for the management of TNBC. Moreover, our results indicate that STAT3 may be targeted for the development of novel anti-TNBC drugs.

A mono-carbonyl analog of curcumin induces apoptosis in drug-resistant EGFR-mutant lung cancer through the generation of oxidative stress and mitochondrial dysfunction.

INTRODUCTION: Targeted therapies using epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) have revolutionized the treatment of non-small cell lung cancer (NSCLC) patients harboring EGFR mutations, leading to the approval of gefitinib and erlotinib as standard first-line clinical treatment. Inevitably, a considerable proportion of patients develop resistance to EGFR-TKIs due to the acquisition of secondary mutations within EGFR. Therefore, alternative strategies to target NSCLC are desperately needed. MATERIALS AND METHODS: In this study, we have evaluated the effect of a reactive oxygen species (ROS)-inducing agent WZ35, a mono-carbonyl analog of curcumin, to target an inherent biological property of cancer cells, increased oxidative stress. To study whether WZ35 can inhibit NSCLC tumorigenesis, we used gefitinib- and erlotinib-resistant cell line H1975. RESULTS: In this study, we show that WZ35 treatment dramatically decreases cell viability and induces apoptosis in H1975 cells through the generation of ROS. We also found that the antitumor activity of WZ35 involved ROS-mediated activation of the endoplasmic reticulum stress pathway and mitochondrial dysfunction. Furthermore, WZ35 significantly inhibited H1975 xenograft tumor growth through the inhibition of cell proliferation and induction of apoptosis. DISCUSSION: These findings show that WZ35 may be a promising candidate for the treatment of EGFR-TKI-resistant NSCLC.

Schisandrin B exhibits potent anticancer activity in triple negative breast cancer by inhibiting STAT3.

Triple negative breast cancer (TNBC) is an aggressive subgroup of human breast cancer. In this study, we have examined the potential of Schisandrin B (Sch B), a bioactive chemical compound found in Schisandra chinensis, against TNBC. We used MDA-MB-231, BT-549, and MDA-MB-468 TNBC cells and immunodeficient mice to study the effect of Sch B. Our results show that Sch B inhibits TNBC growth by inducing cell cycle arrest and by triggering apoptotic death. Sch B also inhibited the migration and colony formation of tumor cells, and prevented the growth of TNBC cells in mice. We found that these inhibitory activities were mediated through suppression of signal transducer and activator of transcription-3 (STAT3) phosphorylation and nuclear translocation. Taken together, our studies show that Sch B has potent anti-tumor activity against TNBC via a novel mechanism involving STAT3 inactivation.