Identification of novel prognostic risk signature of breast cancer based on ferroptosis-related genes.

Ferroptosis is a type of cell regulated necrosis triggered by intracellular phospholipid peroxidation, which is more immunogenic than apoptosis. Therefore, genes controlling ferroptosis may be promising candidate biomarkers for tumor therapy. In this study, we investigate the function of genes associated with ferroptosis in breast cancer (BC) and systematically evaluate the relationship between ferroptosis-related gene expression and prognosis of BC patients from the Cancer Genome Atlas database. By using the consensus clustering method, 1203 breast cancer samples were clustered into two clearly divided subgroups based on the expression of 237 ferroptosis-related genes. Then differentially expressed analysis and least absolute shrinkage and selection operator were used to identify the prognosis-related genes. Furthermore, the genetic risk signature was constructed using the expression of prognosis-related genes. Our results showed that the genetic risk signature can identify patient subgroups with distinct prognosis in either training cohort or validation, and the genetic risk signature was associated with the tumor immune microenvironment. Finally, the Cox regression analysis indicated that our risk signature was an independent prognostic factor for BC patients and this signature was verified by the polymerase chain reaction and western blot. Within this study, we identified a novel prognostic classifier based on five ferroptosis-related genes which may provide a new reference for the treatment of BRCA patients.

The role of surgery on locoregional treatment of patients with breast cancer newly diagnosed with ipsilateral supraclavicular lymph node metastasis.

Background: Radiotherapy is a practical locoregional treatment approach for women with breast cancer who show ipsilateral supraclavicular lymph node metastasis (ISLNM) on diagnosis. However, there is controversy around the role of supraclavicular lymph node dissection. Therefore, we aimed to study the significance of supraclavicular surgery based on radiotherapy. Patients and Methods: We retrospectively reviewed the data of 142 patients with breast cancer who presented with isolated ISLNM and received radiotherapy between the years 2000 and 2016. We also defined the effect of surgery on locoregional treatment of these patients by analyzing the prognostic factors for recurrence-free survival (RFS), distant metastasis-free survival (DMFS), and overall survival (OS). Results: We observed that, of the 142 patients, 104 who received radiotherapy underwent supraclavicular lymph node dissection. Also, among the study group, the progesterone receptor (PR) status (P = 0.044) and the number of axillary lymph nodes (ALNs) involved (P = 0.002) were significant independent predictors of RFS. Also, tumor size (P = 0.007), PR (P < 0.001), and number of ALNs (P < 0.001) were independent predictors of DMFS and were statistically significant. Also, PR was an independent prognostic factor of OS (P = 0.033), whereas the supraclavicular surgery was not an independent prognostic factor for RFS, DMFS, and OS. Furthermore, our study focused on 92 patients with negative estrogen receptors (ERs). The result showed that supraclavicular surgery was statistically significant for RFS (P = 0.023); no significant differences in DMFS and OS were found between patients who received supraclavicular surgery and those who did not. Conclusion: Radiotherapy may be the primary locoregional treatment approach for patients with breast cancer who present with newly diagnosed ISLNM. Additionally, supraclavicular surgery may be more appropriate for patients with negative ER who received radiotherapy.

Development and Validation of a Prognostic Classifier Based on Lipid Metabolism-Related Genes for Breast Cancer.

Background: The changes of lipid metabolism have been implicated in the development of many tumors, but its role in breast invasive carcinoma (BRCA) remains to be fully established. Here, we attempted to ascertain the prognostic value of lipid metabolism-related genes in BRCA. Methods: We obtained RNA expression data and clinical information for BRCA and normal samples from public databases and downloaded a lipid metabolism-related gene set. Ingenuity Pathway Analysis (IPA) was applied to identify the potential pathways and functions of Differentially Expressed Genes (DEGs) related to lipid metabolism. Subsequently, univariate and multivariate Cox regression analyses were utilized to construct the prognostic gene signature. Functional enrichment analysis of prognostic genes was achieved by the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Kaplan-Meier analysis, Receiver Operating Characteristic (ROC) curves, clinical follow-up results were employed to assess the prognostic potency. Potential compounds targeting prognostic genes were screened by Connectivity Map (CMap) database and a prognostic gene-drug interaction network was constructed using Comparative Toxicogenomics Database (CTD). Furthermore, we separately validated the selected marker genes in BRCA samples and human breast cancer cell lines (MCF-7, MDA-MB-231). Results: IPA and functional enrichment analysis demonstrated that the 162 lipid metabolism-related DEGs we obtained were involved in many lipid metabolism and BRCA pathological signatures. The prognostic classifier we constructed comprising SDC1 and SORBS1 can serve as an independent prognostic marker for BRCA. CMap filtered 37 potential compounds against prognostic genes, of which 16 compounds could target both two prognostic genes were identified by CTD. The functions of the two prognostic genes in breast cancer cells were verified by cell function experiments. Conclusion: Within this study, we identified a novel prognostic classifier based on two lipid metabolism-related genes: SDC1 and SORBS1. This result highlighted a new perspective on the metabolic exploration of BRCA.

Catheter malposition analysis of totally implantable venous access port in breast cancer patients.

Background: To investigate the occurrence of catheter malposition in breast cancer patients undergoing Totally Implantable Venous Access Port (TIVAP) implantation and analyze the effect of TIVAP implantation site on the incidence of catheter malposition. Methods: Clinical data of Breast cancer patients underwent TIVAP implantation in our department from 2017 to 2021 was collected by reviewing the electronic medical records. The catheter malposition rate, location and management of malposed catheters in TIVAP implantation were analyzed. We divided the patients into the left internal jugular vein (IJV) group and the right IJV group according to the site of TIVAP implantation and compared the difference in the catheter malposition incidence between the two groups. In addition, we counted the catheter malposition rate of TIVAP implantion via the left and right IJV in right breast cancer patients to analyze the effect of tumor status on the side of TIVAP implantation on the catheter malposition rate. Results: A total of 1,510 catheters were implanted in 1,504 patients, and 16 (1.06%) had catheter malposition. The catheter malposition rate was 4.96% (7/141) for TIVAP implanted via the left IJV and 0.66% (9/1,369) for right IJV, with a statistically significant difference (χ 2 = 18.699, P < 0.05). 743 TIVAPs were implanted in patients with right-sided breast tumor, of which the incidence of catheter malposition was 5.15% (7/136) for TIVAP implanted via left IJV and 0.82% (5/607) for right IJV, with a statistically significant difference (χ 2 = 10.290, P < 0.05). Malposed catheters were found in the subclavian vein, IJV, brachiocephalic vein, internal thoracic vein, undefined collateral veins, and outside the blood vessels. All malposed catheters were successfully adjusted to the proper position by simple manipulative repositioning or percutaneous positioning with the assistance of digital subtraction angiography (DSA), except for 1 case was removed the port because the catheter tip was located outside the vessel. Conclusion: The catheter malposition rate of ultrasound-guided TIVAP implantation via IJV is low, and the malposed catheter can be successfully adjusted to the proper position by simple manipulative repositioning or DSA-assisted percutaneous positioning, however, the catheter malposition incidence of TIVAP implanted via left IJV is higher than that via the right side.

Screening of DNA Damage Repair Genes Involved in the Prognosis of Triple-Negative Breast Cancer Patients Based on Bioinformatics.

Background: Triple-negative breast cancer (TNBC) is a special subtype of breast cancer with poor prognosis. DNA damage response (DDR) is one of the hallmarks of this cancer. However, the association of DDR genes with the prognosis of TNBC is still unclear. Methods: We identified differentially expressed genes (DEGs) between normal and TNBC samples from The Cancer Genome Atlas (TCGA). DDR genes were obtained from the Molecular Signatures Database through six DDR gene sets. After the expression of six differential genes were verified by quantitative real-time polymerase chain reaction (qRT-PCR), we then overlapped the DEGs with DDR genes. Based on univariate and LASSO Cox regression analyses, a prognostic model was constructed to predict overall survival (OS). Kaplan-Meier analysis and receiver operating characteristic curve were used to assess the performance of the prognostic model. Cox regression analysis was applied to identify independent prognostic factors in TNBC. The Human Protein Atlas was used to study the immunohistochemical data of six DEGs. The prognostic model was validated using an independent dataset. Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes analysis were performed by using gene set enrichment analysis (GSEA). Single-sample gene set enrichment analysis was employed to estimate immune cells related to this prognostic model. Finally, we constructed a transcriptional factor (TF) network and a competing endogenous RNA regulatory network. Results: Twenty-three differentially expressed DDR genes were detected between TNBC and normal samples. The six-gene prognostic model we developed was shown to be related to OS in TNBC using univariate and LASSO Cox regression analyses. All the six DEGs were identified as significantly up-regulated in the tumor samples compared to the normal samples in qRT-PCR. The GSEA analysis indicated that the genes in the high-risk group were mainly correlated with leukocyte migration, cytokine interaction, oxidative phosphorylation, autoimmune diseases, and coagulation cascade. The mutation data revealed the mutated genes were different. The gene-TF regulatory network showed that Replication Factor C subunit 4 occupied the dominant position. Conclusion: We identified six gene markers related to DDR, which can predict prognosis and serve as an independent biomarker for TNBC patients.

Case Report: Significant Efficacy of Pyrotinib in the Treatment of Extensive Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer Cutaneous Metastases: A Report of Five Cases.

BACKGROUND: Breast cancer (BC) is the most common tumor to develop cutaneous metastases. Most BCs with cutaneous metastasis are human epidermal growth factor receptor 2 (HER2)-positive subtypes. Although the molecular mechanisms of breast cancer metastasis to different sites and the corresponding treatment methods are areas of in-depth research, there are few studies on cutaneous metastasis. CASE PRESENTATION: Five HER2-positive BC patients with extensive cutaneous metastases were treated with a regimen containing pyrotinib, a novel small-molecule tyrosine kinase inhibitor that irreversibly blocks epidermal growth factor receptor (EGFR), HER2, and human epidermal growth factor receptor 4 (HER4), then their cutaneous metastases quickly resolved at an astonishing speed and their condition was well controlled during the follow-up period. CONCLUSIONS: This case series reports the significant therapeutic effect of pyrotinib on cutaneous metastases of HER2-positive BC for the first time. Based on this, we recommend that pyrotinib can be used as a supplement to trastuzumab for HER2-positive BC patients with cutaneous metastases. In addition, we should consider that the pan-inhibitory effect of pyrotinib on EGFR, HER2, and HER4 may provide a dual therapeutic effect against HER2 and mucin 1.

SNHG5 Promotes Breast Cancer Proliferation by Sponging the miR-154-5p/PCNA Axis.

Breast cancer is the most common malignant tumor and the main cause of cancer-associated mortality in females worldwide. Long non-coding RNAs (lncRNAs) have been reported to play vital roles in breast cancer development and progression; however, our understanding of most lncRNAs in breast cancer is still limited. In this study, we demonstrated that small nucleolar RNA host gene 5 (SNHG5) promotes breast cancer cell proliferation both in vitro and in vivo, and depletion of SNHG5 significantly led to cell-cycle arrest at G1 phase. Accumulating evidence has shown that many lncRNA transcripts could function as competing endogenous RNAs (ceRNAs) by competitively binding common microRNAs (miRNAs). We found that SNHG5 acts as a sponge for miR-154-5p, reducing its ability to repress proliferating cell nuclear antigen (PCNA). SNHG5 promoted breast cancer proliferation and cell-cycle progression by upregulation of PCNA expression. Clinically, we observed an increased SNHG5 expression in breast cancer, whereas miR-154-5p was decreased in breast cancer tissues compared with the adjacent normal breast tissues. Furthermore, the SNHG5 expression was significantly negatively correlated with miR-154-5p expression. Taken together, our data uncover the SNHG5-miR-154-5p-PCNA axis and provide a novel mechanism to explain breast cancer proliferation.

Estrogen receptor-α-miR-1271-SNAI2 feedback loop regulates transforming growth factor-ß-induced breast cancer progression.

BACKGROUND: Breast cancer is the most common cancer among women worldwide, and approximately 70% of breast cancers are hormone receptor-positive and express estrogen receptor-α (ERα) or/and progesterone receptor. ERα has been identified to promote the growth of primary breast cancer, however, it can also antagonize signaling pathways that lead to epithelial-mesenchymal transition (EMT), including transforming growth factor-ß (TGF-ß) signaling. miRNA alteration or dysfunction is involved in cancer development and progression. Although miR-1271 has identified as a tumor suppressor in various cancers, the role of miR-1271 in breast cancer is still limited. METHODS: The effect of miR-1271 on breast cancer progression was investigated both in vitro and in vivo. The EMT-related protein expression levels and localization were analyzed by western blotting and immunofluorescence, respectively. Chromatin immunoprecipitation and dual-luciferase reporter assays were used to validate the regulation of ERα-miR-1271-SNAI2 feedback loop. RESULTS: miR-1271 suppresses breast cancer progression and EMT phenotype both in vitro and in vivo by targeting SNAI2. Estrogen reverses TGF-ß-induced EMT in a miR-1271 dependent manner. Furthermore, ERα transactivates the miR-1271 expression and is also transcriptionally repressed by SNAI2. CONCLUSIONS: Our data uncover the ERα-miR-1271-SNAI2 feedback loop and provide a mechanism to explain the TGF-ß network in breast cancer progression.

miR-190 enhances endocrine therapy sensitivity by regulating SOX9 expression in breast cancer.

BACKGROUND: Breast cancer is the most common cancer among women worldwide, and approximately 70% of breast cancers are hormone receptor-positive and express estrogen receptor-α (ERα) or/and progesterone receptor. Therapies targeting ERα have been successfully used in patients with ERα+ breast cancer. However, intrinsic or acquired resistance to anti-estrogen therapy presents a major challenge. The Wnt/ß-catenin signaling pathway regulates various processes that are important for cancer progression, and emerging evidences have shown a close interaction between Wnt/ß-catenin and ERα signaling. miR-190 is also involved in ER signaling and our previous study indicated that miR-190 suppresses breast cancer metastasis. METHODS: The effect of miR-190 on breast cancer anti-estrogen sensitivity was investigated both in vitro and in vivo. The protein expression levels and localization were analyzed by western blotting and immunofluorescence, respectively. Chromatin immunoprecipitation and dual-luciferase reporter assays were used to validate the regulation of the zinc-finger E-box binding homeobox 1/ ERα-miR-190-SRY-related high mobility group box 9 (ZEB1/ERα-miR-190-SOX9) axis. RESULTS: miR-190 increased the anti-estrogen sensitivity of breast cancer cells both in vitro and in vivo. miR-190 inhibited Wnt/ß-catenin signaling by targeting SOX9, and its expression inversely correlated with that of SOX9 in breast cancer samples. Furthermore, ERα and ZEB1 competitively regulated miR-190 expression. CONCLUSIONS: Our data uncover the ZEB1/ERα-miR-190-SOX9 axis and suggest a mechanism by which the Wnt/ß-catenin signaling pathway is involved in breast cancer anti-estrogen therapy.

miR-485-5p suppresses breast cancer progression and chemosensitivity by targeting survivin.

Breast cancer is the most common cancer among women worldwide. Chemoresistance remains to be a considerable obstacle in breast cancer therapy and it is often involves dysregulation of a variety of microRNAs (miRNAs). miR-485-5p functions as a tumor suppressor in several types of human cancers. However, its role in breast cancer chemosensitivity have not been determined. In the present study, we demonstrated that overexpression of miR-485-5p suppresses breast cancer progression and enhances chemosensitivity both in vitro and in vivo. Further study demonstrated that miR-485-5p directly targeted the 3'-untranslated region of survivin and overexpression of survivin overcomes the miR-485-5p induced effects on breast cancer. In conclusion, our study identified that miR-485-5p suppresses cancer progression and enhances the chemosensitivity by targeting survivin. Targeting survivin by miR-485-5p may provide a potential approach to reverse chemosensitivity in breast cancer cells.

miR-190 suppresses breast cancer metastasis by regulation of TGF-ß-induced epithelial-mesenchymal transition.

BACKGROUND: Breast cancer is the most common cancer among women worldwide and metastasis is the leading cause of death among patients with breast cancer. The transforming growth factor-ß (TGF-ß) pathway plays critical roles during breast cancer epithelial-mesenchymal transition (EMT) and metastasis. SMAD2, a positive regulator of TGF-ß signaling, promotes breast cancer metastasis through induction of EMT. METHODS: The expression of miR-190 and SMAD2 in breast cancer tissues, adjacent normal breast tissues and cell lines were determined by RT-qPCR. The protein expression levels and localization were analyzed by western blotting and immunofluorescence. ChIP and dual-luciferase report assays were used to validate the regulation of ZEB1-miR-190-SMAD2 axis. The effect of miR-190 on breast cancer progression was investigated both in vitro and in vivo. RESULTS: miR-190 down-regulation is required for TGF-ß-induced EMT. miR-190 suppresses breast cancer metastasis both in vitro and in vivo by targeting SMAD2. miR-190 expression is down-regulated and inversely correlates with SMAD2 in breast cancer samples, and its expression level was associated with outcome in patients with breast cancer. Furthermore, miR-190 is transcriptionally regulated by ZEB1. CONCLUSIONS: Our data uncover the ZEB1-miR-190-SMAD2 axis and provide a mechanism to explain the TGF-ß network in breast cancer metastasis.

The combined pN stage and breast cancer subtypes in breast cancer: a better discriminator of outcome can be used to refine the 8th AJCC staging manual.

BACKGROUND: pN stage and breast cancer subtypes (BCS) are both well-recognized prognostic indicators. Our previous work has highlighted that patients even with the same pN stage exhibited a significant survival difference in different BCS. Given this achievement, we hypothesized that a statistical interaction might exist between pN stage and BCS. The aim of this retrospective cohort study was to compare the prognostic value of the combined pN stage and BCS (pNnew stage) with either pN stage or BCS alone, and to determine if this combined new stage could serve as an alternative discriminator of outcome. METHODS: We combined pN stage and BCS to create a new variable named pNnew stage and then divided it into four groups: pN0new, pN1new, pN2new, and pN3new. Survival analysis was performed with the use of the Kaplan-Meier method and the log-rank test was used for univariate analysis. For multivariate analysis, cox proportional hazard models were applied, allowing for the estimation of disease-free survival (DFS). To assess discriminatory accuracy of the models, we compared the area under the receiver-operating characteristic curve (AUROC), the Akaike information criterion (AIC), and the Bayesian information criterion (BIC) values. Then, we used this pNnew stage to generate a TNnewM staging system according to the 7th AJCC staging system. RESULTS: A statistical interaction between pN stage and BCS was found. In multivariate survival analysis, the pNnew stage has been confirmed as an independent prognostic variable of 5-year DFS. The pNnew stage, with a smaller AIC or BIC value and larger AUROC, was a more powerful predictor of DFS than either pN stage or BCS alone. Results were validated in a separate cohort of patients. The TNnewM stage proposed in our present study was found comparable to the new 8th AJCC edition which includes anatomic T, N, and M plus tumor grade and the status of the biomarkers Her-2, ER, and PR with respect to prognostic value for breast cancer patients. CONCLUSIONS: The pNnew stage (combined pN stage and BCS) appears to be a more powerful predictor and discriminator for the outcome of breast cancer, as compared to pN stage or BCS alone, and the TNnewM stage may serve as a simple, easy-to-use alternative to the 8th AJCC edition staging manual.

The prognostic value of node status in different breast cancer subtypes.

Nodal metastases and breast cancer subtypes (BCS) are both well-recognized prognostic indicators. However, the association between nodal metastases and BCS, and the prognostic value of nodal metastases in different BCS are still remains unclear. Our aim was to investigate the association between nodal metastases and BCS, and the prognostic value of nodal metastases in the different BCS.We found that the breast cancer subtype was closely associated with the pN stage. pN stage and breast cancer subtype were significantly associated with disease-free survival. The subgroup analysis showed that the patients in higher pN stage had a poor outcome than patients in lower pN stage in each breast cancer subtype. Furthermore, when the analysis was stratified by breast cancer subtype, we found that even in the same pN stage (pN0-pN2), there was significant survival difference among patients in different BCS, and Luminal A breast cancer patients had the best survival outcome. However, there were no significant survival difference between Luminal A patients and other breast cancer subtype when patients in pN3 stage. Thus, our study suggested that both lymph node status and molecular subtype played important roles in the outcome of breast cancer patients and they cannot replace each other.

Serum deprivation response inhibits breast cancer progression by blocking transforming growth factor-ß signaling.

Serum deprivation response (SDPR), a key substrate for protein kinase C, play a critical role in inducing membrane curvature and participate in the formation of caveolae. However, the function of SDPR in cancer development and progression is still not clear. Here, we found that SDPR is downregulated in human breast cancer. Overexpression of SDPR suppresses cell proliferation and invasion in MDA-MB-231 cells, while depletion of SDPR promotes cell proliferation and invasion in MCF10A cells. Subsequently, SDPR depletion induces epithelial-mesenchymal transition (EMT)-like phenotype. Finally, knockdown of SDPR activates transforming growth factor-ß (TGF-ß) signaling by upregulation of TGF-ß1 expression. In conclusion, our results showed that SDPR inhibits breast cancer progression by blocking TGF-ß signaling. Serum deprivation response suppresses cell proliferation and invasion in breast cancer cells. SDPR depletion induces epithelial-mesenchymal transition by activation of TGF-ß signaling.