Knowledge mapping of immunotherapy for breast cancer: A bibliometric analysis from 2013 to 2022.

Breast cancer is the leading cause of cancer-related death among women globally. Immunotherapy has emerged as a major milestone in contemporary oncology. This study aims to conduct a bibliometric analysis in the field of immunotherapy for breast cancer, providing a comprehensive overview of the current research status, identifying trends and hotspots in research topics. We searched and retrieved data from the Web of Science Core Collection, and performed a bibliometric analysis of publications on immunotherapy for breast cancer from 2013 to 2022. Current status and hotspots were evaluated by co-occurrence analysis using VOSviewer. Evolution and bursts of knowledge base were assessed by co-citation analysis using CiteSpace. Thematic evolution by bibliometrix package was used to discover keywords trends. The attribution and collaboration of countries/regions, institutions and authors were also explored. A total of 7,975 publications were included. In co-occurrence analysis of keywords, 6 major clusters were revealed: tumor microenvironment, prognosis biomarker, immune checkpoints, novel drug delivery methods, immune cells and therapeutic approaches. The top three most frequently mentioned keywords were tumor microenvironment, triple-negative breast cancer, and programmed cell death ligand 1. The most productive country, institution and author were the USA (2926 publications), the University of Texas MD Anderson Cancer Center (219 publications), and Sherene Loi (28 publications), respectively. There has been a rapid growth in studies on immunotherapy for breast cancer worldwide. This research area has gained increasing attention from different countries and institutions. With the rising incidence of breast cancer, immunotherapy represents a research field of significant clinical value and potential.

EIF4A3-induced circZFAND6 promotes breast cancer proliferation and metastasis through the miR-647/FASN axis.

AIMS: Circular RNAs (circRNAs) are important regulators in breast cancer progression. However, the underlying mechanism of circRNAs functions in breast cancer remain largely unclear. MAIN METHODS: To investigate the circRNAs expression pattern in breast cancer, high-throughput circRNA microarray assay was used. The top up-regulated circRNA, circZFAND6, was submitted to further experiments, including cell counting kit-8 (CCK-8) assay, colony formation assay, transwell assay and mouse xenograft assay. To investigate the underlying mechanism of circZFAND6 function in breast cancer progression, luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted. KEY FINDINGS: We found a novel circRNA, circZFAND6, was up-regulated in breast cancer tissues and cell lines. Inhibition of circZFAND6 reduced proliferation and metastasis of breast cancer. Mechanically, circZFAND6 acted as a competing endogenous RNA (ceRNA) to sponge miR-647 and increase fatty acid synthase (FASN) expression. And eukaryotic translation initiation factor 4A3 (EIF4A3) was found to bind to circZFAND6 pre-mRNA transcript upstream region, leading to the high expression of circZFAND6 in breast cancer. Inhibition of EIF4A3 also suppressed proliferation and metastasis of breast cancer. SIGNIFICANCE: EIF4A3-induced circZFAND6 up-regulation promoted proliferation and metastasis of breast cancer through the miR-647/FASN axis. Our results uncovered a possible mechanism underlying breast cancer progression and might provide a breast cancer treatment target.

Long Non-Coding RNA LINC00052 Targets miR-548p/Notch2/Pyk2 to Modulate Tumor Budding and Metastasis of Human Breast Cancer.

Abnormal expression of long non-coding RNAs (lncRNAs) is involved in many pathological processes of cancers. However, the role of lncRNA LINC00052 in breast cancer progression is still unclear. Here, LINC00052 expression was detected by in situ hybridization and quantitative real-time PCR assays. Cell Counting Kit-8, wound healing, and transwell assays were used to investigate changes in the proliferation, migration, and invasion of breast cancer cells. MiR-548p was found associated with LINC00052 or Notch2 by RNA pull-down, dual-luciferase reporter, and qRT-PCR assays. The effect of LINC00052 on lung metastasis was explored through in vivo experiments. High LINC00052 expression was observed in breast cancer tissues and cells. LINC00052 silencing inhibited the proliferation, migration, and invasion of MCF7 cells, and LINC00052 overexpression produced the opposite results. MiR-548p, a target gene of LINC00052, partially rescued the effects of LINC00052 on proliferation, migration, and invasion of MCF7. Notch2 was the target of miR-548p and LINC00052 could promote Notch2 expression. Moreover, the phosphorylation of proline-rich tyrosine kinase 2 (Pyk2), a downstream factor of Notch2, was increased by LINC00052, and a Pyk2 mutant could inhibit the cell migration and invasion induced by LINC00052 overexpression in MDA-MB-468 cells, which was similar to the function of the miR-548p mimic. We further demonstrated that LINC00052 exacerbated the metastases of breast cancer cells in vivo. Our research demonstrated that LINC00052 is highly expressed in breast cancer and promotes breast cancer proliferation, migration, and invasion via the miR-548p/Notch2/Pyk2 axis. LINC00052 could serve as a potential therapeutic target for breast cancer.

Construction and validation of a prognostic nutritional index-based nomogram for predicting pathological complete response in breast cancer: a two-center study of 1,170 patients.

Background: Pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) is associated with favorable outcomes in breast cancer patients. Identifying reliable predictors for pCR can assist in selecting patients who will derive the most benefit from NAC. The prognostic nutritional index (PNI) serves as an indicator of nutritional status and systemic immune competence. It has emerged as a prognostic biomarker in several malignancies; however, its predictive value for pCR in breast cancer remains uncertain. The objective of this study is to assess the predictive value of pretreatment PNI for pCR in breast cancer patients. Methods: A total of 1170 patients who received NAC in two centers were retrospectively analyzed. The patients were divided into three cohorts: a training cohort (n=545), an internal validation cohort (n=233), and an external validation cohort (n=392). Univariate and multivariate analyses were performed to assess the predictive value of PNI and other clinicopathological factors. A stepwise logistic regression model for pCR based on the smallest Akaike information criterion was utilized to develop a nomogram. The C-index, calibration plots and decision curve analysis (DCA) were used to evaluate the discrimination, calibration and clinical value of the model. Results: Patients with a high PNI (≥53) had a significantly increased pCR rate (OR 2.217, 95% CI 1.215-4.043, p=0.009). Tumor size, clinical nodal status, histological grade, ER, Ki67 and PNI were identified as independent predictors and included in the final model. A nomogram was developed as a graphical representation of the model, which incorporated the PNI and five other factors (AIC=356.13). The nomogram demonstrated satisfactory calibration and discrimination in the training cohort (C-index: 0.816, 95% CI 0.765-0.866), the internal validation cohort (C-index: 0.780, 95% CI 0.697-0.864) and external validation cohort (C-index: 0.714, 95% CI 0.660-0.769). Furthermore, DCA indicated a clinical net benefit from the nomogram. Conclusion: The pretreatment PNI is a reliable predictor for pCR in breast cancer patients. The PNI-based nomogram is a low-cost, noninvasive tool with favorable predictive accuracy for pCR, which can assist in determining individualized treatment strategies for breast cancer patients.

CCL18 promotes breast cancer progression by exosomal miR-760 activation of ARF6/Src/PI3K/Akt pathway.

The small GTPase ADP-ribosylation factor 6 (ARF6) mediates chemokine (C-C motif) ligand 18 (CCL18)-induced activation of breast cancer (BC) metastasis through its downstream effector AMAP1. However, the molecular mechanisms underlying CCL18 up-regulating ARF6 remain largely unclear. Here, microRNAs (miRNAs) that target ARF6 were predicted and selected in high metastatic BC cells treated with CCL18. Next, we assessed the role of exosomal miR-760 in vitro and in vivo. We further analyzed the expression of ARF6, AMAP1, and phosphorylated (p)-AMAP1 in tumor and adjacent normal tissues. We first observed that CCL18 increased the expression of ARF6 and p-AMAP1 and activated the Src/phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. ARF6 knockdown significantly impaired CCL18-induced malignant cellular behaviors and the Src/PI3K/Akt signaling pathway. Next, ARF6 was confirmed as a target gene of miR-760 in exosomes derived from CCL18-stimulated high metastatic BC cells. Moreover, recipient MCF-7 cells could effectively uptake these miR-760-rich exosomes that significantly promoted proliferation, tumor growth in vivo, migration, invasion, and chemoresistance by activating ARF6-mediated Src/PI3K/Akt signaling and the epithelial-mesenchymal transition (EMT) pathway. Together, our results support that exosomal miR-760 secreted by CCL18-stimulated high metastatic BC cells promoted the malignant behaviors in low metastatic BC cells by up-regulating the ARF6-mediated Src/PI3K/Akt signaling pathway.

Inhibitor of glutamine metabolism V9302 promotes ROS-induced autophagic degradation of B7H3 to enhance antitumor immunity.

Despite the enormous successes of anti-PD-1/PD-L1 immunotherapy in multiple other cancer types, the overall response rates of breast cancer remain suboptimal. Therefore, exploring additional immune checkpoint molecules for potential cancer treatment is crucial. B7H3, a T-cell coinhibitory molecule, is specifically overexpressed in breast cancer compared with normal breast tissue and benign lesions, making it an attractive therapeutic target. However, the mechanism by which B7H3 contributes to the cancer phenotype is unclear. Here we show that the expression of B7H3 is negatively related to the number of CD8+ T cells in breast tumor sites. In addition, analysis of the differentially expressed B7H3 reveals that it is inversely correlated to autophagic flux both in breast cancer cell lines and clinical tumor tissues. Furthermore, block of autophagy by bafilomycin A1 (Baf A1) increases B7H3 levels and attenuates CD8+ T cell activation, while promotion of autophagy by V9302, a small-molecule inhibitor of glutamine metabolism, decreases B7H3 expression and enhances granzyme B (GzB) production of CD8+ T cells via regulation of reactive oxygen species (ROS) accumulation. We demonstrate that combined treatment with V9302 and anti-PD-1 monoclonal antibody (mAb) enhances antitumor immunity in syngeneic mouse models. Collectively, our findings unveil the beneficial effect of V9302 in boosting antitumor immune response in breast cancer and illustrate that anti-PD-1 together with V9302 treatment may provide synergistic effects in the treatment of patients insensitive to anti-PD-1 therapy.

Construction and Validation of a Serum Albumin-to-Alkaline Phosphatase Ratio-Based Nomogram for Predicting Pathological Complete Response in Breast Cancer.

BACKGROUND: Breast cancer patients who achieve pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) have favorable outcomes. Reliable predictors for pCR help to identify patients who will benefit most from NAC. The pretreatment serum albumin-to-alkaline phosphatase ratio (AAPR) has been shown to be a prognostic predictor in several malignancies, but its predictive value for pCR in breast cancer is still unknown. This study aims to investigate the predictive role of AAPR in breast cancer patients and develop an AAPR-based nomogram for pCR rate prediction. METHODS: A total of 780 patients who received anthracycline and taxane-based NAC from January 2012 to March 2018 were retrospectively analyzed. Univariate and multivariate analyses were performed to assess the predictive value of AAPR and other clinicopathological factors. A nomogram was developed and calibrated based on multivariate logistic regression. A validation cohort of 234 patients was utilized to further validate the predictive performance of the model. The C-index, calibration plots and decision curve analysis (DCA) were used to evaluate the discrimination, calibration and clinical value of the model. RESULTS: Patients with a lower AAPR (<0.583) had a significantly reduced pCR rate (OR 2.228, 95% CI 1.246-3.986, p=0.007). Tumor size, clinical nodal status, histological grade, PR, Ki67 and AAPR were identified as independent predictors and included in the final model. The nomogram was used as a graphical representation of the model. The nomogram had satisfactory calibration and discrimination in both the training cohort and validation cohort (the C-index was 0.792 in the training cohort and 0.790 in the validation cohort). Furthermore, DCA indicated a clinical net benefit from the nomogram. CONCLUSIONS: Pretreatment serum AAPR is a potentially valuable predictor for pCR in breast cancer patients who receive NAC. The AAPR-based nomogram is a noninvasive tool with favorable predictive accuracy for pCR, which helps to make individualized treatment strategy decisions.

A ferroptosis-associated gene signature for the prediction of prognosis and therapeutic response in luminal-type breast carcinoma.

Ferroptosis is a new form of regulated cell death (RCD), and its emergence has provided a new approach to the progression and drug resistance of breast cancer (BRCA). However, there is still a great gap in the study of ferroptosis-related genes in BRCA, especially luminal-type BRCA patients. We downloaded the mRNA expression profiles and corresponding clinical data of BRCA patients from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and The Cancer Genome Atlas (TCGA) databases. Then, we built a prognostic multigene signature with ferroptosis-related differentially expressed genes (DEGs) in the METABRIC cohort and validated it in the TCGA cohort. The predictive value of this signature was investigated in terms of the immune microenvironment and the probability of a response to immunotherapy and chemotherapy. The patients were divided into a high-risk group and a low-risk group according to the ferroptosis-associated gene signature, and the high-risk group had a worse overall survival (OS). The risk score based on the 10 ferroptosis-related gene-based signature was determined to be an independent prognostic predictor in both the METABRIC and TCGA cohorts (HR, 1.41, 95% CI, 1.14-1.76, P = 0.002; HR, 2.19, 95% CI, 1.13-4.26, P = 0.02). Gene set enrichment analysis indicated that the term "cytokine-cytokine receptor interaction" was enriched in the high-risk score subgroup. Moreover, the immune infiltration scores of most immune cells were significantly different between the two groups, the low-risk group was much more sensitive to immunotherapy, and six drugs might have potential therapeutic implications in the high-risk group. Finally, a nomogram incorporating a classifier based on the 10 ferroptosis-related genes, tumor stage, age and histologic grade was established. This nomogram showed favorable discriminative ability and could help guide clinical decision-making for luminal-type breast carcinoma.

Construction and Validation of an Immune Infiltration-Related Gene Signature for the Prediction of Prognosis and Therapeutic Response in Breast Cancer.

Breast cancer patients show significant heterogeneity in overall survival. Current assessment models are insufficient to accurately predict patient prognosis, and models for predicting treatment response are lacking. We evaluated the relationship between various immune cells and breast cancer and confirmed the association between immune infiltration and breast cancer progression. Different bioinformatics and statistical approaches were combined to construct a robust immune infiltration-related gene signature for predicting patient prognosis and responses to immunotherapy and chemotherapy. Our research found that a higher immune infiltration-related risk score (IRS) indicates that the patient has a worse prognosis and is not very sensitive to immunotherapy. In addition, a new nomogram was constructed based on the gene signature and clinicopathological features to improve the risk stratification and quantify the risk assessment of individual patients. Our study might contribute to the optimization of the risk stratification for survival and the personalized management of breast cancer.

Assessment of the Predictive Role of Serum Lipid Profiles in Breast Cancer Patients Receiving Neoadjuvant Chemotherapy.

PURPOSE: Effective predictors of the response to neoadjuvant chemotherapy (NAC) are still insufficient. This study aimed to investigate the predictive value of serum lipid profiles for the response to NAC in breast cancer patients. METHODS: A total of 533 breast cancer patients who had received NAC were retrospectively studied. The pretreatment of serum lipids, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and lipoprotein-α, and clinicopathological characteristics were collected to assess their predictive roles. RESULTS: Breast cancer patients had significantly lower TC, TG, HDL-C, and LDL-C levels than normal individuals. Among these indicators, TG and LDL-C levels and HDL-C level increased and decreased significantly after NAC, respectively. In estrogen receptor (ER)-positive patients, increased LDL-C level was associated with better outcomes. Moreover, the receiver operating characteristic curve analyses suggested that TG and HDL-C levels at diagnosis can be used as predictors of the response to NAC only in the ER-positive subgroup. According to univariate analyses, patients with low TG level (< 1.155 mmol/L) or high HDL-C level (≥ 1.305 mmol/L) in the ER-positive subgroup had more favorable clinical responses than the other patients in the subgroup. Furthermore, according to multivariate analyses, a high HDL-C level (≥ 1.305 mmol/L, p = 0.007) was an independent predictor of NAC efficacy. CONCLUSION: High HDL-C level (≥ 1.305 mmol/L) before NAC and increased LDL-C level after NAC were associated with the better treatment response in ER-positive breast cancer patients. These results are potentially considered beneficial in establishing treatment decisions.

Low pretreatment lymphocyte/monocyte ratio is associated with the better efficacy of neoadjuvant chemotherapy in breast cancer patients.

The combination of some parameters, including the neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), lymphocyte to monocyte ratio (LMR) and neutrophil to monocyte ratio (NMR), which are associated with patient prognosis, our goal is to find the best indicator to predict the efficacy of neoadjuvant chemotherapy（NAC）in breast cancer patients. A cohort of 808 breast cancer patients treated with NAC and subsequent surgery was analyzed retrospectively. In addition, 2424 people without breast cancer served as the normal group, which included three-fold more individuals compared with the breast cancer group. Receiver operating characteristics (ROC) curves were used to determine the optimal cutoff values of inflammatory markers and compare their predictive capacity. No significant differences in age, PLR, LMR and NMR were noted between the normal group and the patient group. However, the mean value of the NLR was significantly increased in breast cancer patients (2.28) compared with the normal population (2.04) (P < .05). The LMR was significantly associated with age (P = .003), menopausal status (P = .004), cT category (P = .017), cN category (P = .024) and response to NAC (P = .001). The multivariate analysis indicated that among these inflammatory markers, the LMR (6.1 < vs ≥ 6.1) was the only independent predictive factor for the efficacy of NAC (OR = 1.771, 95% CI = 1.273-2.464, P = .001). A low LMR is considered a favorable predicative factor of the efficacy of NAC in breast cancer patients.

Sulfasalazine­induced ferroptosis in breast cancer cells is reduced by the inhibitory effect of estrogen receptor on the transferrin receptor.

The aim of the present study was to clarify the activation of ferroptosis in different breast cancer cells by sulfasalazine (SAS) and to explore the relationship between the estrogen receptor (ER) and the transferrin receptor (TFRC). MDA­MB­231 and T47D cells were treated with SAS for 24 h. Changes in cell morphology were observed under a microscope. CCK­8 was used to detect the proliferation inhibition rate and determine the IC50 values. Western blotting was used to detect the expression of glutathione peroxidase 4 (GPX4) and xCT. Flow cytometry was used to identify changes in the production of reactive oxygen species (ROS). Mitochondrial morphological changes in T47D were observed using transmission electron microscopy. Changes in the mitochondrial membrane potential (MMP) were observed using confocal fluorescence microscopy. RT­PCR was used to detect the mRNA expression levels of TFRC and divalent metal transporter 1 (DMT1). Bioinformatics analysis was performed on TFRC expression in 1,208 breast cancer samples and its relationship with ER. TFRC expression was detected in various breast cancer tissues using immunohistochemistry and in various breast cancer cells using western blotting. Small interfering RNA (siRNA) knocked down ER expression in T47D cells, and changes in the TFRC mRNA and protein levels were observed. RT­PCR was used to detect TFRC expression in 87 clinical specimens. The results of the present study revealed that SAS could inhibit breast cancer cell viability, which was accompanied by an abnormal increase in ROS and a depletion of GPX4 and system xc­. Liproxstatin­1 reversed the SAS­induced increase in ROS. The cells treated with SAS had shrunken mitochondria and decreased MMP. SAS upregulated TFRC and DMT1. Knockdown of the ER increased TFRC expression in breast cancer cells. Immunohistochemistry indicated that TFRC expression was lower in ER+ tissues than in ER­ tissues. After confirmation with RT­PCR in 87 clinical specimens, TFRC expression in ER­ tissue was revealed to be significantly higher than that of ER+ tissue. In conclusion SAS could trigger ferroptosis in breast cancer cells, especially in cells with low ER expression. Therefore, SAS is a potential agent for breast cancer treatment.

Assessment of the predictive role of pretreatment Ki-67 and Ki-67 changes in breast cancer patients receiving neoadjuvant chemotherapy according to the molecular classification: a retrospective study of 1010 patients.

PURPOSE: To assess the predictive role of pretreatment ki67 and Ki67 changes in breast cancer (BC) patients treated with neoadjuvant chemotherapy (NAC) in various molecular subtypes. METHODS: 1010 BC patients who had undergone anthracycline and taxane-based NAC from January 2012 to July 2017 were retrospectively analyzed. Clinical and pathological parameters of the patients were retrieved and the predictive factors for NAC response were evaluated. RESULTS: 705 patients showed clinical response (cRes), and 131 patients acquired pathologic complete response (pCR). Patients with higher pretreatment Ki67 (≥ 14%), tumor size ≥ 4 cm, and positive clinical nodal had better clinical therapy response, while patients with negative ER and PR, higher pretreatment Ki67 (≥ 14%), and tumor size < 4 cm were more probable to attain pCR. The pretreatment Ki67 could be used as a predictor of NAC only in luminal subtypes, and 25.5% were identified as an ideal cut-off point to differentiate the cRes from non-cRes cases. Although a decrease in Ki67 had been found in almost all molecular subtypes after NAC, no statistically significant differences were found in the decrease of Ki67 were validated between the cRes and non-cRes group in HER2-rich and triple-negative subtypes (P = 0.488 and P = 0.111, respectively). CONCLUSIONS: The best cut-off for pretreatment Ki67 in predicting the connection with the tumor size lessening was 25.5% in luminal subtype. Aggressive adjuvant systemic treatments should be considered for patients with HER2-rich and triple-negative subtype who exhibit tumor shrinkage in NAC but still have high levels of Ki67.