Tumor-derived small extracellular vesicles promote breast cancer progression by upregulating PD-L1 expression in macrophages.

BACKGROUND: The metastasis of breast cancer (BC) is a complex multi-step pathological process, strictly dependent on the intrinsic characteristics of BC cells and promoted by a predisposing microenvironment. Although immunotherapy has made important progress in metastasis BC, the heterogeneity of PD-L1 in tumor associated macrophages (TAMs) in BC and the underlying mechanisms in the metastasis development of BC are still not completely elucidated. Small extracellular vesicles (sEVs) represent essential interaction mediators between BC cells and TAMs. It is worth noting to explore the underlying mechanisms typical of sEVs and their role in the metastasis development of BC. METHODS: The structure of sEVs was identified by TEM, while the particle size and amounts of sEVs were detected by BCA and NTA analysis. The specific PD-L1 + CD163 + TAM subpopulation in metastasis BC was identified by scRNA-seq data of GEO datasets and verified by IHC and IF. The function of TAMs and sEVs in metastasis BC was explored by RT-qPCR, WB, IF, flow cytometry and in vivo experiment. The expression profiles of plasma sEVs-miRNA in relation to BC metastasis was analyzed using next-generation sequencing. Further detailed mechanisms of sEVs in the metastasis development of BC were explored by bioinformatics analysis, RT-qPCR, WB and luciferase reporter assay. RESULTS: In this study, we identified that the immunosuppressive molecule PD-L1 was more abundant in TAMs than in BC cells, and a specific PD-L1 + CD163 + TAM subpopulation was found to be associated with metastasis BC. Additionally, we found that BC cells-derived sEVs can upregulate the PD-L1 expression and induce the M2 polarization, enhancing the metastasis development both in vitro and in vivo. Also, Clinical data showed that sEV-miR-106b-5p and sEV-miR-18a-5p was in relation to BC metastasis development and poor prognosis of BC patients. Further mechanistic experiments revealed that BC-derived sEV-miR-106b-5p and sEV-miR-18a-5p could synergistically promoted the PD-L1 expression in M2 TAMs by modulating the PTEN/AKT and PIAS3/STAT3 pathways, resulting in the enhancement of the BC cells invasion and metastasis. CONCLUSIONS: Our study demonstrated that BC-derived sEVs can induce metastasis in BC through miR-106b-5p/PTEN/AKT/PD-L1 and miR-18a-5p/PIAS3/STAT3/PD-L1 pathways in TAMs. Therefore, the inhibition of these specific interactions of signaling pathways would represent a promising target for future therapeutic strategies for treatment of BC.

Hyperthermia promotes M1 polarization of macrophages via exosome-mediated HSPB8 transfer in triple negative breast cancer.

PURPOSE: To investigate the mechanism underlying the modulation of M1 macrophage polarization by exosomes released from hyperthermia-treated triple-negative breast cancer (TNBC) cells. MATERIALS AND METHODS: In this study, the effects of hyperthermia on TNBC cells were examined using cell counting kit-8, apoptosis, and cell cycle assays. Transmission electron microscopy was used to identify the structure of exosomes, while bicinchoninic acid and nanoparticle tracking analysis were used to detect particle size and amounts of exosomes released after hyperthermia. The polarization of macrophages incubated with exosomes derived by hyperthermia-pretreated TNBC cells were assessed by RT-qPCR and flow cytometry analysis. Next, RNA sequencing was performed to determine the targeting molecules changed in hyperthermia-treated TNBC cells in vitro. Finally, the mechanism underlying the modulation of macrophage polarization by exosomes derived from hyperthermia-treated TNBC cells was examined by using RT-qPCR, immunofluorescence and flow cytometry analysis. RESULTS: Hyperthermia markedly reduced cell viability in TNBC cells and promoted the secretion of TNBC cell-derived exosomes. The hub genes of hyperthermia-treated TNBC cells were significantly correlated with macrophage infiltration. Additionally, hyperthermia-treated TNBC cell-derived exosomes promoted M1 macrophage polarization. Furthermore, the expression levels of heat shock proteins, including HSPA1A, HSPA1B, HSPA6, and HSPB8, were significantly upregulated upon hyperthermia treatment, with HSPB8 exhibiting the highest upregulation. Moreover, hyperthermia can induce M1 macrophage polarization by promoting exosome-mediated HSPB8 transfer. CONCLUSION: This study demonstrated a novel mechanism that hyperthermia can induce M1 polarization of macrophages via exosome-mediated HSPB8 transfer. These results will help with future development of an optimized hyperthermia treatment regime for clinical application, especially for combination treatment with immunotherapy.

CBX3 promotes breast cancer progression and high level of CBX3 predicts poor prognosis in patients.

Breast cancer is one of the leading cancer deaths around the world. Targeted drugs have greatly increased the survival rate of breast cancer patients in recent years. But in some patients, the current regimen is still ineffective. Therefore, more therapeutic targets for treating breast cancer are demanding. The core heterochromatin-related genes of breast cancer were identified by utilizing prognostic survival analysis and multivariate Cox hazard proportional regression analysis. Both breast cancer and adjacent normal tissue were collected and analyzed with western blot and immunohistochemistry. Colony formation assay, CCK-8 assay, and EdU assay were used to measure the effect of CBX3 on breast cancer cell growth, wound-healing assay and Transwell assay were used to analyze the effect of CBX3 on breast cancer cell migration and invasion. Flow cytometry assay and western blot were used to study the molecular mechanism of CBX3 in breast cancer. High expression of heterochromatin-related proteins CBX3, H2AFY, and SULF1 showed a poor prognosis in patients in both TCGA dataset and GEO datasets. Western blot demonstrated that the expression level of CBX3 was significantly higher in breast cancer than that in adjacent normal tissues. Colony formation assay, CCK-8 assay, and EdU assay showed that the knockdown of CBX3 could significantly inhibit breast cancer cell growth, and the overexpression of CBX3 could promote the growth of breast cancer cells. Transwell assay and wound healing assay showed that knockdown of CBX3 inhibited breast cancer cell migration and invasion, and the overexpression of CBX3 promoted breast cancer cell migration and invasion. Western blot showed that CBX3 might promote breast cancer cell proliferation, invasion, and migration in breast cancer by modulating the ERK1/2 signaling pathway and epithelial-mesenchymal transition (EMT)-related genes. CBX3 was a biomarker of poor prognosis in breast cancer patients. CBX3 promoted the proliferation of breast cancer cells through the ERK signaling pathway, and migration and invasion of breast cancer cells through EMT-related genes. The CBX3/p-ERK1/2 signaling axis might provide a new therapeutic method against breast cancer.

Vaspin accelerates the proliferation, invasion and metastasis of Triple-Negative breast cancer through MiR-33a-5p/ABHD2.

OBJECTIVE: To explore the influence and the underlying mechanism of vaspin (visceral adipose tissue-derived serpin) on the development of triple-negative breast malignancy. METHODS: First, we analyzed medical records and screened out 22 breast cancer patients with different BMI according to inclusion and exclusion criterion, and measured serum vaspin of those patients. Then we studied the effects of vaspin on TNBC cell lines by using EdU assay, colony formation, transwell and wound-healing assay. Later, we used bioinformatics analysis to identify downstream effectors and verify with qRT-PCR, luciferase assay, western blot, etc. RESULTS: We found the vaspin level was positively correlated with BMI in breast malignant patients and vaspin could significantly enhance the proliferation, infiltration and transferring of triple-negative breast cancer cells by restraining the expression of miR-33a-5p. By using bioinformatic analysis and luciferase assay, we identified miR-33a-5p directly regulating ABHD2. CONCLUSION: Vaspin, as a cancer-promoting cytokine, may inhibit miR-33a-5p thus increasing the level of ABHD2 to promote the development of the triple-negative breast cancer.

Dietary patterns, nutritional status, and mortality risks among the elderly.

Introduction: While most epidemiological studies have focused on the effects of individual dietary patterns and nutritional status on health, the relationships between the combinations of these factors and patient prognosis requires further investigation. Objective: This study explored mortality risk in individuals with different combinations of dietary patterns or nutritional status. Methods: Unsupervised K-means clustering was used to classify populations. The analyses included Cox proportional risk and competing risk models. Results: After considering a complex sampling design, the results showed that among 12,724 participants aged >60 years, 6.99% died from cancer and 10.47% from cardiovascular and cerebrovascular disease (CCVD). After correcting for participant baseline information and chronic conditions, the geriatric nutritional risk index and healthy eating index (HEI) were negatively associated with the risk of all-cause and cause-specific mortality. The opposite was true for the dietary inflammatory index (DII). After sorting the population three clusters based on study scores showed higher risks of all-cause mortality and cancer-related death in Cluster 2 and 3. Discussion: These results suggest that different nutritional status and dietary patterns are associated with the risk of all-cause mortality and death from cancer and CCVD in people aged >60 years in the United States. Dietary patterns with high HEI and low DII were beneficial to health, whereas nutritional status needs to be maintained at a level that is not too low.

Endoplasmic reticulum stress targeted therapy for breast cancer.

Recurrence, metastasis, and drug resistance are still big challenges in breast cancer therapy. Internal and external stresses have been proven to substantially facilitate breast cancer progression through molecular and systemic mechanisms. For example, endoplasmic reticulum stress (ERS) results in activation of the unfolded protein response (UPR), which are considered an important cellular stress response. More and more reports indicate its key role in protein homeostasis and other diverse functions involved in the process of breast cancer progression. Therefore, therapies targeting the activation of ERS and its downstream signaling pathways are potentially helpful and novel tools to counteract and fight breast cancer. However, recent advances in our understanding of ERS are focused on characterizing and modulating ERS between healthy and disease states, and so little attention has been paid to studying the role and clinical application of targeting ERS in a certain cancer. In this review, we summarize the function and main mechanisms of ERS in different molecular types of breast cancer, and focus on the development of agents targeting ERS to provide new treatment strategies for breast cancer. Video Abstract.

Potential values of circulating tumor cell for detection of recurrence in patients of thyroid cancer: a diagnostic meta-analysis.

BACKGROUND: Several studies have reported that circulating tumor cells (CTCs) are a promising marker for the diagnosis of thyroid cancer (TC) with recurrence or distant metastasis (DMs). However, some studies emerged with conflicting results. Therefore, we provide a meta-analysis to evaluate the diagnostic performance of CTC for detection of recurrence in patients of TC. METHODS: We searched PubMed, Web of Science, Cochrane library with the keywords "thyroid cancer" and "circulating tumor cells". Data extraction and risk of bias assessment were performed independently by two reviewers. The summary receiver operating characteristic curve (SROC) and other parameters were adopted to summarize the overall test performance. The sensitivity of CTCs in the detection of recurrent TC was reviewed. All analyses were performed by STATA 12.0 and Meta-disc software. RESULTS: For CTCs expressing epithelial cell adhesion molecule (EpCAM), seven studies were included in our meta-analysis. Pooled sensitivity, specificity, and diagnostic odds ratio were 0.71 (95% CI: 0.63-0.78), 0.89 (95% CI: 0.84-0.94), and 26.75 (95% CI: 9.11-78.53); 0.78 (95% CI: 0.65-0.89), 0.88 (95% CI: 0.76-0.96), and 40.01 (95% CI: 10.49-152.63) for CTCs expressing thyroid stimulating hormone receptor (TSHR). The area under the SROC for EpCAM and TSHR were both 0.91. CONCLUSION: CTC was a reliable marker for the diagnosis of TC patients with recurrence and DMs, and the sensitivity of CTCs expressing TSHR was higher than that of EpCAM. Additional research is warranted in order to establish uniformity in international guidelines, make up the drawbacks of conventional diagnostic methods and to prevent futile surgery.

Diagnostic accuracy of de-escalated surgical procedure in axilla for node-positive breast cancer patients treated with neoadjuvant systemic therapy: A systematic review and meta-analysis.

BACKGROUND: More initial clinical node-positive breast cancer patients achieve axillary pathological complete response (ax-pCR) after neoadjuvant systemic therapy (NST). Restaging axillary status and performing de-escalated surgical procedures to replace routine axillary lymph nodes dissection (ALND) is urgently needed. Targeted axillary lymph node biopsy (TLNB) is a novel de-escalated surgical strategy marking metastatic axillary nodes before NST and targeted dissection and biopsy intraoperatively to tailor individual axillary management. METHODS: This study provided a systematic review and meta-analysis to evaluate the feasibility and diagnosis accuracy of TLNB. Prospective and retrospective clinical trials on TLNB were searched from Pubmed, Embase, and Cochrane. Identification rate (IFR), false-negative rate (FNR), negative predictive value (NPV), and rate of ax-pCR were the outcomes of this meta-analysis. RESULTS: One thousand nine hundred and twenty patients attempted TLNB, with an overall IFR of 93.5% (95% confidence interval [CI] 90.1%-96.2%). IFR of three nodal marking methods, namely iodine seeds, clips, and carbon dye, was 95.6% (95% CI 91.2%-98.7%), 91.7% (95% CI 87.3%-95.4%), and 97.1% (95% CI 89.1%-100.0%), respectively. Of them, 847 patients received ALND, with an overall FNR of 5.5% (95% CI 3.3%-8.0%), and NPV ranged from 90.1% to 96.1%. Regression analysis showed that the overlap of targeted and sentinel biopsied nodes might associate with IFRs and FNRs. CONCLUSION: TLNB is a novel, less invasive surgical approach to distinguish initial node-positive breast cancer that achieves negative axillary conversion after NST. It yields an excellent IFR with a low FNR and a high NPV. A combination of preoperative imaging, intraoperative TLNB with SLNB, and postoperative nodal radiotherapy might affect the future treatment paradigm of primary breast cancer with nodal metastases.

Variation of Long Non-Coding RNA And mRNA Profiles in Breast Cancer Cells With Influences of Adipocytes.

BACKGROUND: It is well known that obesity is one of the risks for incurrence and development in breast cancer patients. Long non-coding RNAs (lncRNAs) are reported to participate in the composition of tumor microenvironment and to regulate breast cancer cell metabolic activities. However, there was rare study focused on the lncRNAs in breast cancer with the influences of adipocytes. The study aimed to investigate lncRNAs expression profiles and discover potential biomarkers to predict the incidence and progression of adipocyte-associated-breast cancer. METHODS: We co-cultured adipocytes with breast cancer cells and profiled the expression of lncRNAs as well as mRNAs by using the RNA-sequencing method. Wound Healing, Migration assays and Invasion assays were applied to verify the invasion and metastasis of cancer cells. RESULTS: MDA-MB-231/Hpa-V and SK-BR-3/Hpa-V cells showed elevated migration and invasiveness compared to the control group. A sum of 371 mRNAs (181 upregulated and 190 downregulated) and 850 lncRNAs(414 upregulated and 436 downregulated) were differentially expressed in MDA-MB-231/Hpa-V comparing to MDA-MB-231(P < 0.05; |log2 (fold change)|>1.2). GO enrichment, KEGG pathway and interaction networks demonstrated that differentially expressed lncRNAs were involved in functional categories, such as material metabolism, which might lead to the progression of breast cancer. CONCLUSION: Our study detected a lncRNA profile in breast cancer cells affecting by adipocytes and provided a better understanding of the tumor microenvironment. LncRNAs may be helpful to predict the therapeutic responses and prognosis of obese breast cancer patients.

Lignans intake and enterolactone concentration and prognosis of breast cancer: a systematic review and meta-analysis.

Background: Some literature has studied the relationship between lignans intake and its metabolite, enterolactone, and breast cancer survival, but the results are far from consistent and conclusive. Therefore, we conducted a systematic review and meta-analysis in this situation. Methods: From its inception to August 2020, we conducted a comprehensive search of PubMed, Embase, Web of Science, and Cochrane Library databases. This study reported the correlation between lignans intake and serum enterolactone concentrations and prognosis of breast carcinoma. The total hazard ratios (HRs) and 95% confidence interval (95% CI) were estimated, comparing the highest versus the lowest category of lignans intake and serum enterolactone concentrations, using a fixed or random-effects effect model. Results: A total of 6 articles were included in reporting the all-cause mortality (ACM), breast cancer-specific mortality (BCSM), and recurrence of 2668, 1516, and 474 breast cancer patients in 18053 breast cancer patients. In postmenopausal women with breast cancer, lignans intake or enterolactone concentrations were associated with a reduced risk of all-cause mortality (maximum and minimum) (pooled HR = 0.73, 95% CI, 0.58-0.91), as was the association with breast cancer-specific mortality (maximum and minimum) (pooled HR = 0.72, 95% CI, 0.60, 0.87). Stratified analysis showed that exposure type and diagnosis time might be the sources of heterogeneity. In premenopausal women, the relationship seemed to be the opposite, showing an increased risk of all-cause mortality (maximum and minimum) in breast cancer patients (pooled HR = 1.57, 95% CI, 1.11-2.23). No significant association was found between lignans intake or enterolactone concentrations and breast cancer recurrence (pooled HR = 0.91, 95% CI, 0.69, 1.20). Conclusion: This study provides limited evidence that lignans intake and higher serum enterolactone concentrations in postmenopausal women are beneficial to breast cancer patients' prognosis. In premenopausal women, however, the relationship may be reversed.