OBJECTIVES: To explore the mechanism by which Pulsatilla saponin D (PSD) inhibits invasion and metastasis of triple-negative breast cancer (TNBC). METHODS: The public databases were used to identify the potential targets of PSD and the invasion and metastasis targets of TNBC to obtain the intersection targets between PSD and TNBC. The "PSD-target-disease" interaction network was constructed and protein-protein interaction (PPI) analysis was performed to obtain the core targets, which were analyzed for KEGG pathway and GO functional enrichment. Molecular docking study of the core targets and PSD was performed, and the therapeutic effect and mechanism of PSD were verified using Transwell assay and Western blotting in cultured TNBC cells. RESULTS: Network pharmacology analysis identified a total of 285 potential PSD targets and 26 drug-disease intersection core targets. GO analysis yielded 175 entries related to the binding of biomolecules (protein, DNA and RNA), enzyme activities, and regulation of gene transcription. KEGG analysis yielded 46 entries involving pathways in cancer, chemical carcinogenesis-receptor activation, microRNAs in cancer, chemical carcinogenesis-reactive oxygen species, PD-L1 expression and PD-1 checkpoint pathway in cancer. Molecular docking showed high binding affinities of PSD to MTOR, HDAC2, ABL1, CDK1, TLR4, TERT, PIK3R1, NFE2L2 and PTPN1. In cultured TNBC cells, treatment with PSD significantly inhibited cell invasion and migration and lowered the expressions of MMP2, MMP9, N-cadherin and the core proteins p-mTOR, ABL1, TERT, PTPN1, HDAC2, PIK3R1, CDK1, TLR4 as well as NFE2L2 expressionin the cell nuclei. CONCLUSIONS The inhibitory effects of PSD on TNBC invasion and metastasis are mediated by multiple targets and pathways.
Humans ; Triple Negative Breast Neoplasms/metabolism* ; Saponins/pharmacology* ; Pulsatilla/chemistry* ; Female ; Molecular Docking Simulation ; Cell Line, Tumor ; Neoplasm Invasiveness ; Protein Interaction Maps ; Neoplasm Metastasis ; Signal Transduction/drug effects* ; Cell Movement/drug effects*

OBJECTIVES: To investigate the effects of dihydroartemisinin (DHA) combined with doxorubicin (DOX) on proliferation and apoptosis of triple-negative breast cancer cells and explore the underlying molecular mechanism. METHODS: MDA-MB-231 cells were treated with 50, 100 or 150 μmol/L DHA, 0.5 μmol/L DOX, or with 50 μmol/L DHA combined with 0.5 μmol/L DOX. The changes in proliferation and survival of the treated cells were examined with MTT assay and colony-forming assay, and cell apoptosis was analyzed with flow cytometry. Western blotting was performed to detect the changes in protein expression levels of PCNA, cleaved PARP, Bcl-2, Bax, STAT3, p-STAT3, HIF-1α and survivin. RESULTS: The IC₅₀ of DHA was 131.37±29.87 μmol/L in MDA-MB-231 cells. The cells with the combined treatment with DHA and DOX showed significant suppression of cell proliferation. Treatment with DHA alone induced apoptosis of MDA-MB-231 cells in a dose-dependent manner, but the combined treatment produced a much stronger apoptosis-inducing effect than both DHA and DOX alone. DHA at 150 μmol/L significantly inhibited clone formation of MDA-MB-231 cells, markedly reduced cellular expression levels of PCNA, p-STAT3, HIF-1α and survivin proteins, and obviously increased the expression level of cleaved PARP protein and the Bax/Bcl-2 ratio, and the combined treatment further reduced the expression level of p-STAT3 protein and increased the Bax/Bcl-2 ratio. CONCLUSIONS DHA combined with DOX produces significantly enhanced effects for inhibiting cell proliferation and inducing apoptosis in MDA-MB-231 cells possibly as result of DHA-mediated negative regulation of the STAT3/HIF-1α pathway.
Humans ; STAT3 Transcription Factor/metabolism* ; Apoptosis/drug effects* ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Doxorubicin/pharmacology* ; Triple Negative Breast Neoplasms/metabolism* ; Cell Line, Tumor ; Artemisinins/pharmacology* ; Female ; Cell Proliferation/drug effects* ; Signal Transduction/drug effects* ; Survivin

Triple-negative breast cancer (TNBC) represents an aggressive breast cancer subtype with poor prognosis and limited targeted treatment options. This investigation examined the anti-cancer potential of Caerulomycin A (Cae A), a natural compound derived from marine actinomycetes, against TNBC. Cae A demonstrated selective inhibition of viability and proliferation in TNBC cell lines, including 4T1, MDA-MB-231, and MDA-MB-468, through apoptosis induction. Mechanistic analyses revealed that the compound induced sustained endoplasmic reticulum (ER) stress and subsequent upregulation of C/EBP homologous protein (CHOP) expression, resulting in mitochondrial damage-mediated apoptosis. Inhibition of ER stress or CHOP expression knockdown reversed mitochondrial damage and apoptosis, highlighting the essential role of ER stress and CHOP in Cae A's anti-tumor mechanism. Both oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) decreased in TNBC cells following Cae A treatment, indicating reduced mitochondrial respiratory and glycolytic capacities. This diminished energy metabolism potentially triggers ER stress and subsequent apoptosis. Furthermore, Cae A exhibited significant anti-tumor effects in the 4T1 tumor model in vivo without apparent toxicity. The compound also effectively inhibited human TNBC organoid growth. These results indicate that Cae A may serve as a potential therapeutic agent for TNBC, with its efficacy likely mediated through the disruption of glucose metabolism and the induction of ER stress-associated apoptosis.
Humans ; Endoplasmic Reticulum Stress/drug effects* ; Triple Negative Breast Neoplasms/genetics* ; Apoptosis/drug effects* ; Cell Line, Tumor ; Female ; Animals ; Glucose/metabolism* ; Mice ; Cell Proliferation/drug effects* ; Transcription Factor CHOP/genetics* ; Antineoplastic Agents/pharmacology* ; Mitochondria/metabolism* ; Mice, Inbred BALB C

OBJECTIVE: To investigate the therapeutic effect of Sanhuang Xiexin Decoction (SXD) on triple-negative breast cancer (TNBC) in mice and its underlying mechanism. METHODS: The high-performance liquid chromatography (HPLC) was used to quantitate and qualify SXD. A total of 15 female BALB/c mice were inoculated subcutaneously on the right hypogastrium with 3×10⁵ of 4T1-Luc cells to establish TNBC mouse model. All mice were divided randomly into 3 groups, including phosphate buffered solution (PBS), SXD and doxorubicin (DOX) groups (positive drug). Additionally, tumor growth, pathological changes, serum lipid profiles, expression of Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signaling pathway and its key targets including inflammatory factors, cell cycle and epithelial-mesenchymal transition (EMT) markers were investigated. Besides, the biosafety of SXD was also evaluated in mice. RESULTS: Rhein, coptisine, berberine hydrochloride and baicalin were all found in SXD, and the concentrations of these 4 components were 0.57, 2.61, 2.93, and 46.04 mg/g, respectively. The mouse experiment showed that SXD could notably suppress the development of tumors and reduce the density of tumor cells (P<0.01). The serum lipid analysis and Oil-Red-O staining both showed the differences, SXD group exhibited higher serum adiponectin and HDL-C levels with lower TC and LDL-C levels compared to the PBS and DOX groups (P<0.05 or P<0.01), respectively. SXD also decreased the levels of phospho-JAK2 (p-JAK2), phospho-STAT3 (p-STAT3) expressions and its downstream factors, including mostly inflammatory cytokine, EMT markers, S phase of tumor cells and vascular endothelial growth factor (VEGF) expression (P<0.05 or P<0.01), respectively. The biosafety assessment of SXD revealed low levels of toxicity in mice. CONCLUSION SXD could inhibit TNBC by suppressing JAK2-STAT3 phosphorylation which may be associated with modulation of lipid metabolism.
Animals ; STAT3 Transcription Factor/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Janus Kinase 2/metabolism* ; Lipid Metabolism/drug effects* ; Female ; Mice, Inbred BALB C ; Triple Negative Breast Neoplasms/metabolism* ; Cell Line, Tumor ; Epithelial-Mesenchymal Transition/drug effects* ; Signal Transduction/drug effects* ; Mice

OBJECTIVE: To investigate the effect of inhibition of RAB27 protein family, which plays a pivotal role in exosome secretion, on biological behaviors of triple-negative breast cancer cells. METHODS: Quantitative real-time PCR and Western blotting were used to examine the expressions of RAB27 family and exosome secretion in 3 triple-negative breast cancer cell lines (MDA-MB-231, MDA-MB-468, and Hs578T) and a normal breast epithelial cell line (MCF10A). The effect of small interfering RNA (siRNA)-mediated silencing of RAB27a and RAB27b on exosome secretion in the 3 breast cancer cell lines was detected using Western blotting, and the changes in cell proliferation, invasion and adhesion were evaluated. RESULTS: Compared with normal breast epithelial cells, the 3 triple-negative breast cancer cell lines exhibited more active exosome secretion (P < 0.001) and showed significantly higher expressions of RAB27a and RAB27b at both the mRNA and protein levels (P < 0.01). Silencing of RAB27a in the breast cancer cells significantly down-regulated exosome secretion (P < 0.001), while silencing of RAB27b did not significantly affect exosome secretion. The 3 breast cancer cell lines with RAB27a silencing-induced down-regulation of exosome secretion showed obvious inhibition of proliferation, invasion and adhesion (P < 0.01) as compared with the cell lines with RAB27b silencing. CONCLUSION RAB27a plays central role in the exosome secretion in triple-negative breast cancer cells, and inhibiting RAB27a can inhibit the proliferation, invasion and adhesion of the cells.
Humans ; rab GTP-Binding Proteins/metabolism* ; Triple Negative Breast Neoplasms ; Cell Line, Tumor ; rab27 GTP-Binding Proteins/metabolism* ; RNA, Small Interfering/genetics* ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic

Objective: To observe the clinical pathology features, and immune microenvironment of HER-2 intratumoral heterogeneity breast cancer. Methods: Thirty cases of HER-2 intratumoral heterogeneous breast cancer were retrospectively analyzed in Tianjin Medical University Cancer Institute and Hospital from November 2017 to June 2020. HER-2 expression was detected by immunohistochemistry and verified by dual color silver-enhanced in-situ hybridization (D-SISH). HER-2 intratumoral positive and negative regions were divided. The pathological characteristics, subtype, and the level of tumor infiltrating lymphocytes (TILs) and the expression of programmed cell death-ligand 1 (PD-L1) were evaluated respectively. Results: The proportion of HER-2 positive cells of the breast cancer ranged from 10% to 90%. The pathological type was mainly invasive non-special typecarcinoma. Six cases presented different pathological types between HER-2 positive and negative regions. The HER-2-positive areas included 2 cases of carcinoma with apocrine differentiation, and the negative areas included 2 cases of invasive micropapillary carcinoma, 1 case of invasive papillary carcinoma, and 1 case of carcinoma with apocrine differentiation. In HER-2 positive regions, 17 cases were Luminal B and 13 cases were HER-2 overexpressed types. There were 22 cases of Luminal B and 8 cases of triple negative tumors in the HER-2 negative areas. The levels of TILs in HER-2 positive and negative areas accounted for 53.3% (16/30) and 26.7% (8/30), respectively, with a statistically significant difference (P=0.035). The positive expression of PD-L1 in HER-2 positive area and HER-2 negative area were 6 cases and 9 cases, respectively. Among 8 cases with HER-2 negative regions containing triple negative components, 4 cases were positive for PD-L1 expression. Conclusions: In the case of HER-2 intratumoral heterogeneity, it is necessary to pay attention to both HER-2 positive and negative regions, and evaluate subtype separately as far as possible. For HER-2 intratumoral heterogeneous breast cancer containing triple negative components, the treatment mode can be optimized by refining the intratumoral expression of PD-L1.
Humans ; Female ; Breast Neoplasms/pathology* ; Retrospective Studies ; B7-H1 Antigen/metabolism* ; Lymphocytes, Tumor-Infiltrating/pathology* ; Carcinoma ; Tumor Microenvironment ; Triple Negative Breast Neoplasms/pathology* ; Prognosis ; Biomarkers, Tumor/metabolism*

Cluster of differentiation 36 (CD36) is a membrane glycoprotein receptor capable of binding and transporting fatty acid. Nogo-B regulates the metabolism of fatty acids in the liver and affects the development of liver cancer. To date, it remains unclear whether the interaction between CD36 and Nogo-B affects the proliferation and migration of breast cancer cells. In the current study, we aimed to determine whether the interference of CD36 and Nogo-B affects the proliferation and migration of triple-negative breast cancer (TNBC) cells. The results showed that inhibition of CD36 or Nogo-B alone can inhibit the proliferation and migration of TNBC cells, and the inhibitory effect was more pronounced when CD36 and Nogo-B were inhibited simultaneously. Meanwhile, it was found that inhibition of CD36 and Nogo-B expression can inhibit the expression of Vimentin, B-cell lympoma-2 (BCL2) and proliferating cell nuclear antigen (PCNA). In vivo, knockdown of CD36 or Nogo-B in E0771 cells reduced its tumorigenic ability, which was further enhanced by knockdown of CD36 and Nogo-B simultaneously. Mechanistically, inhibition of CD36 and Nogo-B expression can decrease fatty acid binding protein 4 (FABP4) and fatty acid transport protein 4 (FATP4) expression. Moreover, overexpression of CD36 and Nogo-B-induced cell proliferation was attenuated by FABP4 siRNA, indicating that inhibition of CD36 and Nogo-B expression could inhibit the absorption and transport of fatty acids, thereby inhibiting the proliferation and migration of TNBC. Furthermore, inhibition of CD36 and Nogo-B expression activated the P53-P21-Rb signaling pathway which contributed to the CD36 and Nogo-B-inhibited proliferation and migration of TNBC. Taken together, the results suggest that inhibition of CD36 and Nogo-B can reduce the proliferation and migration of TNBC, which provides new targets for the development of drugs against TNBC.
Humans ; Triple Negative Breast Neoplasms/metabolism* ; Cell Movement ; Cell Proliferation ; Cell Line, Tumor ; Fatty Acids

This study aims to investigate the effect and mechanism of hydnocarpin(HC) in treating triple negative breast cancer(TNBC). Cell counting kit-8(CCK-8), xCELLigence real-time cellular analysis(RTCA), and colony formation assay were employed to determine the effects of HC on the proliferation of two TNBC cell lines: MDA-MB-231 and MDA-MB-436. The effects of HC on the migration and invasion of TNBC cells were detected by high-content analysis, wound-healing assay, and Transwell assay. The changes in the epithelial-mesenchymal transition(EMT) and the expression of invasion-and migration-associated proteins [E-cadherin, vimentin, Snail, matrix metalloproteinase-2(MMP-2), and MMP-9] were detected by Western blot. Western blot and RT-qPCR were employed to determine the protein and mRNA levels of Yes-associated protein(YAP) and downstream targets(CTGF and Cyr61). TNBC cells were transfected with Flag-YAP for the overexpression of YAP, and the role of YAP as a key target for HC to inhibit TNBC malignant progression was examined by CCK-8 assay, Transwell assay, and wound-healing assay. The pathway of HC-induced YAP degradation was detected by the co-treatment of proteasome inhibitor with HC and ubiquitination assay. The binding of HC to YAP and the E3 ubiquitin ligase Ccr4-not transcription complex subunit 4(CNOT4) was detected by microscale thermophoresis(MST) assay and drug affinity responsive target stability(DARTS) assay. The results showed that HC significantly inhibited the proliferation, colony formation, invasion, and EMT of TNBC cells. HC down-regulated the protein and mRNA levels of CTGF and Cyr61. HC down-regulated the total protein level of YAP, while it had no effect on the mRNA level of YAP. The overexpression of YAP antagonized the inhibitory effects of HC on the proliferation, migration, and invasion of TNBC cells. HC promoted the degradation of YAP through the proteasome pathway and up-regulated the ubiquitination level of YAP. The results of MST and DARTS demonstrated direct binding between HC, YAP, and CNOT4. The above results indicated that HC inhibited the malignant progression of TNBC via CNOT4-mediated degradation and ubiquitination of YAP.
Humans ; Triple Negative Breast Neoplasms/metabolism* ; Matrix Metalloproteinase 2/metabolism* ; Cell Line, Tumor ; Cell Proliferation ; Cell Movement ; Ubiquitination ; RNA, Messenger/metabolism* ; Epithelial-Mesenchymal Transition ; Transcription Factors/metabolism*

Objective: PD-1/PD-L1 immune checkpoint treatment is effective for some triple-negative breast cancer populations with PD-L1 expression, but the response rate is still not satisfactory. This study aims to explore the mechanism of drug resistance to breast cancer anti-PD-1 therapies and the strategies for overcoming the resistance to PD-1therapies. Methods: By constructing a human triple-negative breast cancer drug-resistant cell line called BT-549R5 and a mouse breast cancer drug-resistant cell line called 4T1R3, and applying the whole-gene shRNA library screening, candidate drug resistance-associated molecules were obtained and verified by cytological experiments. The expression of Tyro3, Axl and MerTK of the TAM family in the 4T1R3 group was tested using the Western blot method. The down-regulation of CDK9 on the effect of T cells killing the BT-549R5 cells was observed through T cell killing tests, while the down-regulation of Tyro3 and CDK9 on the effect of anti-PD-1 therapies for transplanted breast tumors was observed in mouse tumor formation experiments. Results: The cell lines and animal models of breast cancer resistant to PD-1 treatment were successfully constructed. Tyro3, Axl and MerTK were highly expressed in 4T1R3 cells. Whole genome sequencing showed that Tyro3 and CDK9 were highly expressed in BT-549R5 cells. T cell killing experiment showed that the survival rate of BT-549R5 cells in the CDK9 down-regulated group and the control group decreased gradually with the increase of T cells, but the survival rate of BT-549R5 cells in the CDK9 down-regulated group decreased rapidly. Tumor formation experiment in mice showed that under anti-PD-1 treatment, the transplanted tumor in the 4T1R3 cell group grew rapidly compared with the 4T1 cell group (P<0.05), and the tumor volume of the 4T1R3 group was larger than that of the 4T1 group on Day 20. Nevertheless, the tumor growth rates in the CDK9-knockdown 4T1R3 cell group and the Tyro3-knockdown 4T1R3 cell group were similar to that of the 4T1 cell group, and the tumor volumes at day 20 were signiference lower than that of 4T1R3 cell group(P<0.05). Conclusions: Tyro3 and CDK9 are associated with the drug resistance to anti-PD-1 therapies for breast cancer. Inhibiting the expression of Tyro3 and CDK9 can reverse the drug resistance to breast cancer treatment.
Humans ; Animals ; Mice ; c-Mer Tyrosine Kinase/metabolism* ; Receptor Protein-Tyrosine Kinases/genetics* ; Axl Receptor Tyrosine Kinase ; Proto-Oncogene Proteins/metabolism* ; B7-H1 Antigen/genetics* ; Triple Negative Breast Neoplasms/genetics* ; Drug Resistance, Neoplasm ; Biomarkers ; Cell Line, Tumor ; Cyclin-Dependent Kinase 9

Objective: To provide survival evidence of anthracycline-free neoadjuvant chemotherapy for patients with stages Ⅱ-Ⅲ human epidermal growth factor receptor-2 (HER-2) positive and hormone receptor (HR) negative breast cancer. Methods: The prospective cohort study was conducted at the Department of Medical Oncology of Cancer Hospital, Chinese Academy of Medical Sciences. Patients with HER-2 positive and HR negative breast cancer in stages Ⅱ-Ⅲ were enrolled to receive neoadjuvant therapy (NAT) of dose-dense paclitaxel (175 mg/m(2)) plus carboplatin (AUC=4.0) biweekly for 6 cycles in combination with trastuzumab (PCbH), and matched patients who received standard adjuvant therapy of physicians' choice were recruited for survival and safety comparison. Results: From July 2013 to November 2019, 166 patients were included (neoadjuvant 51, adjuvant 115). Compared with those who received adjuvant therapy, patients receiving NAT were younger (<35 years: 19.6% vs 5.2%, P=0.014), had larger tumors (T3: 62.7% vs 7.8%, P<0.001) and more advanced diseases (stage ⅡA: 2.0% vs 41.7%, P<0.001). Patients in the neoadjuvant group all received surgery, and 96 (83.5%) in the adjuvant group received anthracycline-and-taxane-containing regimens. A total of 98 patients (49 pairs) were matched, and the covariates between the two groups were acceptably balanced. Within a median follow-up of 46.5 (range, 14-87) months, the 4-year recurrence-free survival (RFS) rate among patients who received NAT was 73.3% (95% CI: 59.0%-87.6%), versus 80.6% (95% CI: 67.9%-93.3%) among those in the adjuvant group without statistical difference (P=0.418). A similar result was observed for the 4-year overall survival (OS) [neoadjuvant versus adjuvant: 91.5% (95% CI: 81.7%-100.0%) vs 97.8% (95% CI: 93.5%-100.0%), P=0.314]. Compared with standard adjuvant therapy, PCbH was related to less neutropenia and better cardiac safety. Conclusions: These results support the consideration of anthracycline-free neoadjuvant chemotherapy combined with anti-HER-2 therapy for patients with stages Ⅱ-Ⅲ HER-2-positive and HR-negative breast cancer. Optimized regimens with both efficacy and safety are needed and to be further investigated.
Female ; Humans ; Anthracyclines/therapeutic use* ; Antibiotics, Antineoplastic/therapeutic use* ; Antineoplastic Combined Chemotherapy Protocols/therapeutic use* ; Carboplatin/therapeutic use* ; Chemotherapy, Adjuvant ; Hormones/therapeutic use* ; Neoadjuvant Therapy ; Paclitaxel/therapeutic use* ; Prospective Studies ; Receptor, ErbB-2/metabolism* ; Trastuzumab/therapeutic use* ; Triple Negative Breast Neoplasms/drug therapy*