Precise nano-system-based drug delivery and synergistic therapy against androgen receptor-positive triple-negative breast cancer.

Targeting androgen receptor (AR) has shown great therapeutic potential in triple-negative breast cancer (TNBC), yet its efficacy remains unsatisfactory. Here, we aimed to identify promising targeted agents that synergize with enzalutamide, a second-generation AR inhibitor, in TNBC. By using a strategy for screening drug combinations based on the Sensitivity Index (SI), we found that MK-8776, a selective checkpoint kinase1 (CHK1) inhibitor, showed favorable synergism with enzalutamide in AR-positive TNBC. The combination of enzalutamide and MK-8776 was found to exert more significant anti-tumor effects in TNBC than the single application of enzalutamide or MK-8776, respectively. Furthermore, a nanoparticle-based on hyaluronic acid (HA)-modified hollow-manganese dioxide (HMnO2), named HMnE&M@H, was established to encapsulate and deliver enzalutamide and MK-8776. This HA-modified nanosystem managed targeted activation via pH/glutathione responsiveness. HMnE&M@H repressed tumor growth more obviously than the simple addition of enzalutamide and MK-8776 without a carrier. Collectively, our study elucidated the synergy of enzalutamide and MK-8776 in TNBC and developed a novel tumor-targeted nano drug delivery system HMnE&M@H, providing a potential therapeutic approach for the treatment of TNBC.

Tumor-derived extracellular vesicles as a biomarker for breast cancer diagnosis and metastasis monitoring.

It is imperative to explore biomarkers that are both precise and readily accessible in the comprehensive management of breast cancer. A multicenter cohort, including 512 breast cancer patients and 198 nonneoplastic individuals, was recruited to detect the level of tumor-derived extracellular vesicles using our method based on dual DNA tetrahedral nanostructures. The level of tumor-derived extracellular vesicles was significantly higher in newly diagnosed breast cancer patients than in nonneoplastic individuals at a cutoff value of 3.58 U/µL. For postoperative metastasis monitoring, the level of tumor-derived extracellular vesicles was significantly higher in breast cancer patients with metastasis than in those without metastasis at a cutoff value of 3.91 U/µL. Its efficacy of diagnosis and metastasis monitoring was superior to traditional tumor markers. Elevated level of tumor-derived extracellular vesicles served as a predictive biomarker for diagnosis and metastasis monitoring in breast cancer patients.

Estrogen receptor beta suppresses the androgen receptor oncogenic effects in triple-negative breast cancer.

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer associated with poor prognosis and limited treatment options. The androgen receptor (AR) has emerged as a potential therapeutic target for luminal androgen receptor (LAR) TNBC. However, multiple studies have claimed that anti-androgen therapy for AR-positive TNBC only has limited clinical benefits. This study aimed to investigate the role of AR in TNBC and its detailed mechanism. METHODS: Immunohistochemistry and TNBC tissue sections were applied to investigate AR and nectin cell adhesion molecule 4 (NECTIN4) expression in TNBC tissues. Then, in vitro and in vivo assays were used to explore the function of AR and estrogen receptor beta (ERß) in TNBC. Chromatin immunoprecipitation sequencing (ChIP-seq), co-immunoprecipitation (co-IP), molecular docking method, and luciferase reporter assay were performed to identify key molecules that affect the function of AR. RESULTS: Based on the TNBC tissue array analysis, we revealed that ERß and AR were positive in 21.92% (32/146) and 24.66% (36/146) of 146 TNBC samples, respectively, and about 13.70% (20/146) of TNBC patients were ERß positive and AR positive. We further demonstrated the pro-tumoral effects of AR on TNBC cells, however, the oncogenic biology was significantly suppressed when ERß transfection in LAR TNBC cell lines but not in AR-negative TNBC. Mechanistically, we identified that NECTIN4 promoter -42 bp to -28 bp was an AR response element, and that ERß interacted with AR thus impeding the AR-mediated NECTIN4 transcription which promoted epithelial-mesenchymal transition in tumor progression. CONCLUSIONS: This study suggests that ERß functions as a suppressor mediating the effect of AR in TNBC prognosis and cell proliferation. Therefore, our current research facilitates a better understanding of the role and mechanisms of AR in TNBC carcinogenesis.

Exploring potential network pharmacology-and molecular docking-based mechanism of melittin in treating rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is a type of difficult-to-cure arthralgia with a worldwide prevalence. It severely affects people's living standards. For a long time, bee venom has been used to treat RA and has shown good results. Melittin is the main active component of bee venom used for RA treatment, but the molecular mechanism of melittin in RA treatments remains unclear. METHODS: Potential melittin and RA targets were obtained from relevant databases, and common targets of melittin and RA were screened. The STRING database was used to build the PPI network and screen the core targets after visualization. The core targets were enriched by Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway. Finally, the binding of melittin to target proteins was evaluated through simulated molecular docking, which verified the reliability of the prediction results of network pharmacology. RESULTS: In total, 138 melittin targets and 5795 RA targets were obtained from relevant databases, and 90 common targets were obtained through intersection. Eighteen core targets, such as STAT3, AKT1, tumor necrosis factor, and JUN, were screened out. Enrichment analysis results suggested that melittin plays an anti-RA role mainly through tumor necrosis factor, interleukin-17, toll-like receptors, and advanced glycation end products-RAGE signaling pathways, and pathogenic bacterial infection. Molecular docking results suggested that melittin has good docking activity with core target proteins. CONCLUSION: RA treatment with melittin is the result of a multi-target and multi-pathway interaction. This study offers a theoretical basis and scientific evidence for further exploring melittin in RA therapy.

Inhibition of MYC suppresses programmed cell death ligand-1 expression and enhances immunotherapy in triple-negative breast cancer.

BACKGROUND: Cancer immunotherapy has emerged as a promising strategy against triple-negative breast cancer (TNBC). One of the immunosuppressive pathways involves programmed cell death-1 (PD-1) and programmed cell death ligand-1 (PD-L1), but many patients derived little benefit from PD-1/PD-L1 checkpoint blockades treatment. Prior research has shown that MYC, a master transcription amplifier highly expressed in TNBC cells, can regulate the tumor immune microenvironment and constrain the efficacy of immunotherapy. This study aims to investigate the regulatory relationship between MYC and PD-L1, and whether a cyclin-dependent kinase (CDK) inhibitor that inhibits MYC expression in combination with anti-PD-L1 antibodies can enhance the response to immunotherapy. METHODS: Public databases and TNBC tissue microarrays were used to study the correlation between MYC and PD-L1. The expression of MYC and PD-L1 in TNBCs was examined by quantitative real-time polymerase chain reaction and Western blotting. A patient-derived tumor xenograft (PDTX) model was used to evaluate the influence of a CDK7 inhibitor THZ1 on PD-L1 expression. Cell proliferation and migration were detected by 5-ethynyl-2'-deoxyuridine (EdU) cell proliferation and cell migration assays. Tumor xenograft models were established for in vivo verification. RESULTS: A high MYC expression level was associated with a poor prognosis and could alter the proportion of tumor-infiltrating immune cells (TIICs). The positive correlation between MYC and PD-L1 was confirmed by immunostaining samples from 165 TNBC patients. Suppression of MYC in TNBC caused a reduction in the levels of both PD-L1 messenger RNA and protein. In addition, antitumor immune response was enhanced in the TNBC cancer xenograft mouse model with suppression of MYC by CDK7 inhibitor THZ1. CONCLUSIONS: The combined therapy of CDK7 inhibitor THZ1 and anti-PD-L1 antibody appeared to have a synergistic effect, which might offer new insight for enhancing immunotherapy in TNBC.

Microenvironment components and spatially resolved single-cell transcriptome atlas of breast cancer metastatic axillary lymph nodes.

As an indicator of clinical prognosis, lymph node metastasis of breast cancer has drawn great attention. Many reports have revealed the characteristics of metastatic breast cancer cells, however, the effect of breast cancer cells on the microenvironment components of lymph nodes and spatial transcriptome atlas remains unclear. In this study, by integrating single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics, we investigate the transcriptional profiling of six surgically excised lymph node samples and the spatial organization of one positive lymph node. We identify the existence of osteoclast-like giant cells (OGC) which have high expressions of CD68 and CD163, the biomarkers of tumor-associated macrophages (TAMs). Through a spatially resolved transcriptomic method, we find that OGCs are scattered among metastatic breast cancer cells. In the lymph node microenvironment with breast cancer cell infiltration, TAMs are enriched in protumoral pathways including NF-κB signaling pathways and NOD-like receptor signaling pathways. Further subclustering demonstrates the potential differentiation trajectory in which macrophages develop from a state of active chemokine production to a state of active lymphocyte activation. This study is the first to integrate scRNA-seq and spatial transcriptomics in the tumor microenvironment of axillary lymph nodes, offering a systematic approach to delve into breast cancer lymph node metastasis.

Dendrobium nobile Lindl. Polysaccharides protect fibroblasts against UVA-induced photoaging via JNK/c-Jun/MMPs pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Dendrobium nobile Lindl. is an orchid species that is found throughout Asia, including Thailand, Laos, Vietnam, and China. It has been used to treat tumors, hyperglycemia, hyperlipidemia, and neurological disorders caused by aging in recent decades. AIM OF THE STUDY: To investigate the antagonistic effect of Dendrobium nobile Lindl. Polysaccharides (DNLP) on UVA-induced photoaging of Human foreskin fibroblasts (HFF-1) and explore its possible anti-aging mechanisms. MATERIALS AND METHODS: An in vitro photoaging model of dermal fibroblasts was established with multiple UVA irradiations. Fibroblasts were treated with 0.06 mg/ml, 0.18 mg/ml, 0.54 mg/ml of DNLP one day before photodamage induction. The levels of reactive oxygen species (ROS), Malondialdehyde (MDA), cell viability and longevity, Superoxide Dismutase (SOD), Catalase (CAT), and Glutathione peroxidase (GSH-Px) enzymatic activities were determined. We examined how DNLP ameliorates the effects of photoaging, the JNK/c-Fos/c-Jun pathway, senescence-associated ß-galactosidase (SA-ß-Gal), and MMP expression levels were measured. RESULTS: UVA irradiation reduced the viability, lifespan, and proliferation of HFF-1 cells, increased ROS and lipid peroxidation and decreased the activities of free radical scavenging enzyme systems SOD, CAT, and GSH-Px. DNLP treatment can reverse UVA damage, reduce SA-ß-Gal expression, reduce phosphorylation activation of the JNK/c-Fos/c-Jun pathway and inhibit MMP-1, MMP-2 MMP-3, and MMP-9 protein expression. CONCLUSIONS: DNLP can effectively inhibit UVA damage to HFF-1 and prevent cell senescence. Its mechanism of action may increase antioxidant enzyme activity while inhibiting JNK pathway activation and MMPs expression.

Preparation and Safety Evaluation of Centella asiatica Total Glycosides Nitric Oxide Gel and Its Therapeutic Effect on Diabetic Cutaneous Ulcers.

Diabetic cutaneous ulcers (DCU) are a chronic and refractory complication of diabetes mellitus, which can lead to amputation or even death in extreme cases. Promoting the early healing of DCU and reducing the disability rate and treatment cost are important research topics in treating with integrated traditional Chinese and Western medicine. Centella asiatica total glycosides are extracted from the traditional Chinese medicine Centella asiatica and have angiogenic, anticancer, antioxidant, and wound healing effects. Nitric oxide (NO) is a critical component of wound healing. During the development of DCU, endogenous NO secretion is insufficient. It has been reported that exogenous nitric oxide can promote wound healing, but it is difficult to adhere to the skin because of its short half-life. Therefore, in this study, we used the polymer excipient hydroxyethyl cellulose as the matrix, combined with Centella asiatica total glycosides and NO, and developed a new type of topical gel that can promote wound healing. At the same time, we made a comprehensive research and evaluation on the preparation technology, quality standard, skin toxicity, reproductive toxicity, and pharmacodynamics against diabetic skin ulcers of the gel. According to our research results, the combination of Centella asiatica total glycosides and nitric oxide can accelerate the healing speed of DCU wounds, and 8% Centella asiatica total glycosides nitric oxide gel (CATGNOG) has the best effect in ulcer wound healing. CATGNOG has the advantages of feasible preparation method, controllable quality, good stability at low temperature, and no apparent skin toxicity and reproductive toxicity. It can effectively inhibit the growth of bacteria on the wound surface, relieve the inflammatory reaction of the wound surface, and promote the healing of ulcer wound, which provides a basis for further research of the preparation in the future.

Single-cell RNA sequencing reveals cell heterogeneity and transcriptome profile of breast cancer lymph node metastasis.

Molecular mechanisms underlying breast cancer lymph node metastasis remain unclear. Using single-cell sequencing, we investigated the transcriptome profile of 96,796 single cells from 15 paired samples of primary tumors and axillary lymph nodes. We identified nine cancer cell subclusters including CD44 + / ALDH2 + /ALDH6A1 + breast cancer stem cells (BCSCs), which had a copy-number variants profile similar to that of normal breast tissue. Importantly, BCSCs existed only in primary tumors and evolved into metastatic clusters infiltrating into lymph nodes. Furthermore, transcriptome data suggested that NECTIN2-TIGIT-mediated interactions between metastatic breast cancer cells and tumor microenvironment (TME) cells, which promoted immune escape and lymph node metastasis. This study is the first to delineate the transcriptome profile of breast cancer lymph node metastasis using single-cell RNA sequencing. Our findings offer novel insights into the mechanisms underlying breast cancer metastasis and have implications in developing novel therapies to inhibit the initiation of breast cancer metastasis.

MYC dysfunction modulates stemness and tumorigenesis in breast cancer.

As a transcription factor and proto-oncogene, MYC is known to be deregulated in a variety of tumors, including breast cancer. However, no consistent conclusion on the role and mechanism of MYC deregulation during breast cancer carcinogenesis has been formed. Here, we used the UALCAN, bc-GenExMiner, TCGA, cBioportal, STRING and Kaplan-Meier Plotter databases to explore the mRNA expression, prognosis, transcriptional profile changes, signal pathway rewiring and interaction with the cancer stem cells of MYC in breast cancer. We found that the expression of MYC varies in different subtypes of breast cancer, with relatively high frequency in TNBC. As a transcription factor, MYC not only participates in the rewiring of cancer signaling pathways, such as estrogen, WNT, NOTCH and other pathways, but also interacts with cancer stem cells. MYC is significantly positively correlated with breast cancer stem cell markers such as CD44, CD24, and ALDH1. Collectively, our results highlight that MYC plays an important regulatory role in the occurrence of breast cancer, and its amplification can be used as a predictor of diagnosis and prognosis. The interaction between MYC and cancer stem cells may play a crucial role in regulating the initiation and metastasis of breast cancer.

A six-gene signature related with tumor mutation burden for predicting lymph node metastasis in breast cancer.

BACKGROUND: Breast cancer (BC) is one of the most common cancers worldwide and patients with lymph node metastasis always suffer from a worse prognosis. Tumor mutation burden (TMB) has been reported as a potential predictor for tumor behaviors. However, the correlation between TMB and lymph node metastasis of BC remains unclear. This study aimed to explore TMB-related biomarkers to predict the lymph node metastasis in BC patients. METHODS: A total of 949 BC patients with RNA-seq data, mutation data and clinical data were obtained from The Cancer Genome Atlas (TCGA) database. We visualized mutation data by "maftools" package. We calculated TMB of each patient and investigated its association with lymph node metastasis. BC patients were divided into lymph node positive and negative groups and we respectively identified TMB-related and lymph node-related differentially expressed genes (DEGs) to figure out intersected genes. Functional enrichment analysis and protein-protein interaction (PPI) network were performed to observe relevant biological functions. We constructed a TMB-related signature for predicting lymph node metastasis through Logistic regression analysis. A validation database (GSE102484) from the Gene Expression Omnibus (GEO) database was downloaded to verify the accuracy. RESULTS: Single nucleotide polymorphism (SNP) occupied the highest proportion in variant types while C>T appeared most frequently in single nucleotide variant (SNV). TMB was regarded as negatively correlated with lymph node metastasis in BC (P=0.003). We identified 125 common DEGs through venn diagram, which were enriched in vesicle localization, calcium signaling pathway and salmonella infection. A TMB-related signature based on six genes (BAHD1, PPM1A, PQLC3, SMPD3, EEF1A1 and S100B) had reliable efficacy for predicting lymph node metastasis in BC and was proven as an independent predictive factor. The accuracy of this signature was further validated by GSE102484 database. CONCLUSIONS: Our results indicated that TMB was associated with lymph node metastasis of BC. We built a TMB-related signature consisting of six genes which might function as a novel biomarker for predicting lymph node metastasis in BC.