Poor Survival In Breast Cancer Research Articles

Abstract 3306: Targeting HER3 receptor positive cancers with a novel anti-HER3 antibody radioconjugate (ARC)

Abstract Background: HER3 overexpression is reported to be associated with poor survival in breast, ovarian, lung, gastric and prostate cancer. In addition, upregulation of HER3 in response to HER1 or HER2 targeted therapies, is implicated in the acquired resistance against these therapies. Therefore, effective targeting of HER3 can potentially overcome resistance and enhance therapeutic efficacy. Although a number of anti-HER3 antibodies have failed clinical testing with the development focus being shifted to other approaches such as antibody drug conjugates and bispecific antibodies, there are currently no approved HER3-targeted therapies. Here we describe a novel approach that can enhance therapeutic efficacy in HER3+ cancer patients by conjugating an anti-HER3 antibody with the alpha-emitting cytotoxic radioisotope Actinium-225 (225Ac) to create an anti-HER3 antibody radiation conjugate (225Ac-HER3-ARC). Alpha emitting radioisotopes like 225Ac can cause double-strand DNA breaks for which there is no known resistance mechanism. Due to the cytotoxic properties of the radioisotope, lower levels of antibody may be needed, resulting in reduced incidence or less severe toxicities. We hypothesize that targeting HER3 in solid tumors with an ARC will result in tumor specific cell killing especially in a setting where HER-targeting agents are not a viable option. We developed a novel 225Ac-HER3-ARC and evaluated its efficacy in HER3+ in vitro and in vivo tumor models. Methods: AT-02, an anti-HER3 antibody, was conjugated with p-SCN-Bn-DOTA and radiolabeled with 225Ac. 225Ac-HER3-ARC specific binding to HER3 was assessed by ELISA using human recombinant HER3 and by flow cytometry on HER3+ cells. The cytotoxic effect of HER3 ARC was evaluated in a panel of HER3 expressing cells. We further evaluated the maximum tolerated dose and therapeutic efficacy of the ARC in nude mice bearing human HER3+ xenograft tumors. Results: In this study we successfully radiolabeled anti-HER3 with 225Ac. 225Ac-HER3-ARC showed similar binding properties to those of the native antibody by ELISA (HER3-ARC: EC50 = 0.0017 µg/ml, HER3 EC50 = 0.0022 µg/ml) and flow cytometry. Treatment with ARC was cytotoxic to HER3+ cells in a dose-dependent manner (EC50 = 54 kBq/ml). 225Ac-HER3-ARC showed potent in vivo efficacy in preclinical solid tumor xenograft models that was correlated with the in vitro cytotoxicity findings. Treatment with 225Ac-HER3-ARC (7.4 - 22.2 kBq, 200 - 600 nCi) led to complete responses and significantly prolonged survival compared to control groups (p < 0.0001). Conclusions: Our findings demonstrate that targeting HER3 with a novel 225Ac-HER3-ARC results in potent tumor cell cytotoxicity and complete anti-tumor response in HER3 tumor xenograft model. This approach provides a promising therapeutic strategy for HER3 positive tumors and warrants further assessment. Citation Format: Denis Beckford-Vera, Jason Li, Megan McCloskey, Caroline Jennings, Amanda Chin, Qing Liang, Jesse Hwang, Monideepa Roy, Mary Chen, Helen Kotanides. Targeting HER3 receptor positive cancers with a novel anti-HER3 antibody radioconjugate (ARC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3306.

Lipid-associated macrophages in the tumor-adipose microenvironment facilitate breast cancer progression

ABSTRACT The tumor-adipose microenvironment (TAME) is a universal microecosystem, that is characterized by the dysfunction of lipid metabolism, such as excessive free fatty acids (FFAs). Macrophages are the most abundant immune cell type within TAME, although their diversity in the TAME is not clear. We first reveal that infiltration of M2-like macrophages in the TAME is associated with poor survival in breast cancer. To explore lipid-associated alterations in the TAME, we also detected the levels of FFAs transporters including fatty acid binding proteins (FABPs) and fatty acid transport protein 1 (FATP1). The results indicated that expression of fatty acid transporters in the TAME is tightly linked to the function of macrophages and predicts survival in breast cancer. To explore the impact of FFAs transporters on the function of macrophages, we performed single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics. Consequently, we identified a special subpopulation of macrophages defined as lipid-associated macrophages (LAMs), highly expressed macrophage markers (CD163, SPP1 and C1QC), genes involved in lipid metabolism (FABP3, FABP4, FABP5, LPL and LIPA) and some lipid receptors (LGALS3 and TREM2). Functionally, LAMs were characterized by a canonical functional signature of M2-like macrophages, lipid accumulation and enhancing phagocytosis, and they were mostly distributed in tumor-adipose junctional regions. Finally, the allograft cancer mouse models confirmed that LAMs depletion in the TAME synergizes the antitumorigenic effects of anti-PD1 therapy. In summary, we defined a novel subtype of macrophages in the TAME, that has unique features and clinical outcomes.

Historical redlining and breast cancer survival in the United States: Evidence from the 2010-2017 SEER Medicare linked dataset.

1095 Background: Cancer is the second leading cause of morbidity and mortality in the US. Systemic racism is a critical cause of health disparities and historically disadvantaged people experience poor outcomes including poor breast cancer (BC) survival. This study aims to investigate the impact of historical redlining on all-cause and BC-specific survival among older women in the US. Methods: Historic 1930’s Homeowner’s Loan Corporation (HOLC) boundaries and grades were linked to 2010 Census tracts and the 2010-2017 SEER Medicare BC cohort. Women were included if they were 66+ years old at diagnosis, diagnosed with invasive BC, enrolled in Medicare Part A and Part B for 12 months prior to diagnosis to calculate comorbidity, and a Census tract match for HOLC grade. The independent variable was HOLC grade in two categories: A and B(not redlined), and C and D(redlined). The outcomes were all-cause and BC-specific survival, determined by Kaplan Meier Survival curves and both unadjusted and adjusted Cox regression models. End point for censoring was 12/31/2019 (all-cause) and 12/31/2018 (BC-specific). The final models were stratified by age and tumor stage at diagnosis; and adjusted for comorbidity, race and ethnicity, hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status, and interaction term between comorbidity and race. Results: Among 10,113 women, 62.8% resided in historically redlined Census tracts. At a mean (+SD) follow-up time of 48.5 (+28.8) months, 28.9% were deceased; 41.6% of which died of BC. Women residing in historically redlined census tracts experienced poorer BC survival (49.8 +28.2 months) than those residing in non-redlined Census tracts (57.8 +30.7 months). After controlling for covariates, residing in a historically redlined Census tract remained an independent predictor of higher mortality: HR (95%CI) = 1.11 (1.02, 1.20) and 1.24 (1.011, 1.39) for all-cause mortality and BC-specific mortality, respectively. Conclusions: Residing in a formerly redlined Census tract at the time of BC diagnosis is associated with worse all-cause and BC-specific mortality, even after stratifying/adjusting for important patient and tumor characteristics. Public health and government agencies stakeholders should consider historical contexts when designing and implementing equity-focused community and clinical interventions targeted at mitigating and reducing BC disparities and improving health equity.

ESR1 inhibits ionizing radiation-induced ferroptosis in breast cancer cells via the NEDD4L/CD71 pathway

Ferroptosis is the name given to the type of non-apoptotic cell death that is caused by iron accumulation and subsequent lipid peroxidation. However, how ionizing radiation (IR)-induced ferroptosis is regulated in estrogen receptor-positive (ER+) breast cancer cells remains unclear. To attempt to resolve this issue, bioinformatics analysis was performed to evaluate the prognostic value of estrogen receptor 1 (ESR1) in breast cancer tissues. A total of four breast cancer cell lines and an MCF10A non-malignant counterpart were used. Western blotting was used to analyze the levels of protein expression, whereas immunoprecipitation (IP) and ubiquitination experiments were used to test protein binding and ubiquitination levels, respectively. Flow cytometry was subsequently used to analyze cell death and lipid peroxidation levels. The results showed that a high expression level of ESR1 was significantly correlated with poor overall survival in breast cancer. ESR1 knockdown significantly enhanced IR-induced ferroptosis and increased the CD71 protein level. The IP results showed that ESR1 enhanced the binding of the E3 ubiquitin ligase NEDD4L to CD71, promoting the ubiquitination and degradation of CD71, suggesting that CD71 expression was regulated by both ESR1 and NEDD4L. Taken together, the findings in the present study have demonstrated a regulatory relationship between ESR1 and NEDD4L/CD71 in IR-induced ferroptosis. In addition, the ESR1/NEDD4L/CD71 axis may be a potential target for the radiotherapy of breast cancer.

Using Weighted Gene Co-Expression Network Analysis to Identify Increased MND1 Expression as a Predictor of Poor Breast Cancer Survival.

ObjectiveWe used bioinformatics analysis to identify potential biomarker genes and their relationship with breast cancer (BC).Materials and MethodsWe used a weighted gene co-expression network analysis (WGCNA) to create a co-expression network based on the top 25% genes in the GSE24124, GSE33926, and GSE86166 datasets obtained from the Gene Expression Omnibus. We used the DAVID online platform to perform GO and KEGG pathway enrichment analyses and the Cytoscape CytoHubba plug-in to screen the potential genes. Then, we related the genes to prognostic values in BC using the Oncomine, GEPIA, and Kaplan–Meier Plotter databases. Findings were validated by immunohistochemical (IHC) staining in the Human Protein Atlas and the TCGA-BRCA cohort. LinkedOmics identified the interactive expressions of hub genes. We used UALCAN to evaluate the methylation levels of these hub genes. MethSurv and SurvivalMeth were used to assess the multilevel prognostic value. Finally, we assessed hub gene association with immune cell infiltration using TIMER.ResultsThe mRNA levels of MKI67, UBE2C, GTSE1, CCNA2, and MND1 were significantly upregulated in BC, whereas ESR1, THSD4, TFF1, AGR2, and FOXA1 were significantly downregulated. The DNA methylation signature analysis showed a better prognosis in the low-risk group. Further subgroup analyses revealed that MND1 might serve as an independent risk factor for unfavorable BC prognosis. Additionally, MND1 expression levels positively correlate with the immune infiltration statuses of CD4+ T cells, CD8+ T cells, B cells, neutrophils, dendritic cells, and macrophages.ConclusionOur results indicate that the ten hub genes may be involved in BC’s carcinogenesis, development, or metastasis, and MND1 may be a potential biomarker and therapeutic target for BC.

Tubulin Carboxypeptidase Activity Promotes Focal Gelatin Degradation in Breast Tumor Cells and Induces Apoptosis in Breast Epithelial Cells That Is Overcome by Oncogenic Signaling.

Simple SummaryThe recent discovery of the genetic identity of the tubulin carboxypeptidase (TCP) provides a unique opportunity to study the role of the detyrosination of α-tubulin (deTyr-Tub), as performed by the TCP, in breast epithelial cells and breast cancer cells. Previous research has shown that elevated deTyr-Tub conveys a poor prognosis in breast cancer and is upregulated in a coordinated manner at the invasive margin of patient tumor samples. Using TCP expression constructs, we have shown that increased deTyr-Tub promotes apoptosis in normal breast epithelial cells, that does not occur in the same cells with an oncogenic KRas mutation or Bcl-2/Bcl-xL overexpression. Furthermore, the addition of the TCP to the breast cancer cell lines MDA-MB-231 and Hs578t, also harboring Ras mutations, leads to increased focal gelatin degradation.Post-translational modifications (PTMs) of the microtubule network impart differential functions across normal cell types and their cancerous counterparts. The removal of the C-terminal tyrosine of α-tubulin (deTyr-Tub) as performed by the tubulin carboxypeptidase (TCP) is of particular interest in breast epithelial and breast cancer cells. The recent discovery of the genetic identity of the TCP to be a vasohibin (VASH1/2) coupled with a small vasohibin-binding protein (SVBP) allows for the functional effect of this tubulin PTM to be directly tested for the first time. Our studies revealed the immortalized breast epithelial cell line MCF10A undergoes apoptosis following transfection with TCP constructs, but the addition of oncogenic KRas or Bcl-2/Bcl-xL overexpression prevents subsequent apoptotic induction in the MCF10A background. Functionally, an increase in deTyr-Tub via TCP transfection in MDA-MB-231 and Hs578t breast cancer cells leads to enhanced focal gelatin degradation. Given the elevated deTyr-Tub at invasive tumor fronts and the correlation with poor breast cancer survival, these new discoveries help clarify how the TCP synergizes with oncogene activation, increases focal gelatin degradation, and may correspond to increased tumor cell invasion. These connections could inform more specific microtubule-directed therapies to target deTyr-tubulin.

High RAD51 gene expression is associated with aggressive biology and with poor survival in breast cancer.

Although the DNA repair mechanism is important in preventing carcinogenesis, its activation in established cancer cells may support their proliferation and aggravate cancer progression. RAD51 cooperates with BRCA2 and is essential in the homologous recombination of DNA repair. To this end, we hypothesized that RAD51 gene expression is associated with cancer cell proliferation and poor prognosis of breast cancer (BC) patients. A total of 8515 primary BC patients with transcriptome and clinical data from 17 independent cohorts were analyzed. The median value was used to divide each cohort into high and low RAD51 expression groups. High RAD51 expression enriched the DNA repair gene set and was correlated with DNA repair-related genes. Nottingham histological grade, Ki67 expression and cell proliferation-related gene sets (E2F Targets, G2M Checkpoint and Myc Targets) were all significantly associated with the high RAD51 BC group. RAD51 expression was positively correlated with Homologous Recombination Deficiency, as well as both mutational burden and neoantigens that accompanied a higher infiltration of immune cells. Primary BC with lymph node metastases was associated with high expression of RAD51 in two cohorts. There was no strong correlation between RAD51 expression and drug sensitivity in cell lines, and RAD51 expression was lower after the neoadjuvant chemotherapy compared to before the treatment. High RAD51 BC was associated with poor prognosis consistently in three independent cohorts. RAD51 gene expression is associated with aggressive cancer biology, cancer cell proliferation, and poor survival in breast cancer.

Loss of ASAP1 in the MMTV-PyMT model of luminal breast cancer activates AKT, accelerates tumorigenesis, and promotes metastasis

ASAP1 is a multi-domain adaptor protein that regulates cytoskeletal dynamics, receptor recycling and intracellular vesicle trafficking. Its expression is associated with poor prognosis in a variety of cancers, and can promote cell migration, invasion and metastasis. Although amplification and expression of ASAP1 has been associated with poor survival in breast cancer, we found that in the autochthonous MMTV-PyMT model of luminal breast cancer, ablation of ASAP1 resulted in an earlier onset of tumor initiation and increased metastasis. This was due to tumor cell-intrinsic effects of ASAP1 deletion, as ASAP1 deficiency in tumor, but not in stromal cells was sufficient to replicate the enhanced tumorigenicity and metastasis observed in the ASAP1-null MMTV-PyMT mice. Loss of ASAP1 in MMTV-PyMT mice had no effect on proliferation, apoptosis, angiogenesis or immune cell infiltration, but enhanced mammary gland hyperplasia and tumor cell invasion, indicating that ASAP1 can accelerate tumor initiation and promote dissemination. Mechanistically, these effects were associated with a potent activation of AKT. Importantly, lower ASAP1 levels correlated with poor prognosis and enhanced AKT activation in human ER+/luminal breast tumors, validating our findings in the MMTV-PyMT mouse model for this subtype of breast cancer. Taken together, our findings reveal that ASAP1 can have distinct functions in different tumor types and demonstrate a tumor suppressive activity for ASAP1 in luminal breast cancer.

SIPL1, Regulated by MAZ, Promotes Tumor Progression and Predicts Poor Survival in Human Triple-Negative Breast Cancer.

BackgroundTriple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer owing to a lack of effective targeted therapy and acquired chemoresistance. Here, we explored the function and mechanism of shank-interacting protein-like 1 (SIPL1) in TNBC progression.MethodsSIPL1 expression was examined in human TNBC tissues and cell lines by quantitative reverse transcription PCR, western blot, and immunohistochemistry. SIPL1 overexpression and silenced cell lines were established in BT-549 and MDA-MB-231 cells. The biological functions of SIPL1 in TNBC were studied in vitro using the CCK-8 assay, CellTiter-Glo Luminescent Cell Viability assay, caspase-3/8/9 assay, wound healing assay, and transwell assay and in vivo using a nude mouse model. The potential mechanisms underlying the effects of SIPL1 on TNBC progression were explored using bioinformatics analysis, luciferase reporter assays, and chromatin immunoprecipitation followed by qPCR.Results SIPL1 expression was higher in human TNBC tissues and cell lines than in adjacent normal tissues and a breast epithelial cell line (MCF10A). High expression of SIPL1 was positively correlated with poor overall and disease-free survival in patients with TNBC. SIPL1 overexpression elevated and SIPL1 silencing repressed the malignant phenotypes of TNBC cells in vitro. SIPL1 overexpression promoted xenograft tumor growth in vivo. Myc-associated zinc-finger protein (MAZ) transcriptionally activated SIPL1. Finally, we found that SIPL1 promoted TNBC malignant phenotypes via activation of the AKT/NF-κB signaling pathways.ConclusionsThese results indicate that the MAZ/SIPL1/AKT/NF-κB axis plays a crucial role in promoting the malignant phenotypes of TNBC cells.

WNT11/ROR2 signaling is associated with tumor invasion and poor survival in breast cancer

BackgroundBreast cancer has been associated with activation of the WNT signaling pathway, although no driver mutations in WNT genes have been found yet. Instead, a high expression of the alternative WNT receptor ROR2 was observed, in particular in breast cancer brain metastases. However, its respective ligand and downstream signaling in this context remained unknown.MethodsWe modulated the expression of ROR2 in human breast cancer cells and characterized their gene and protein expression by RNA-Seq, qRT-PCR, immunoblots and reverse phase protein array (RPPA) combined with network analyses to understand the molecular basis of ROR2 signaling in breast cancer. Using co-immunoprecipitations, we verified the interaction of ROR2 with the identified ligand, WNT11. The functional consequences of WNT11/ROR2 signaling for tumor cell aggressiveness were assessed by microscopy, impedance sensing as well as viability and invasion assays. To evaluate the translational significance of our findings, we performed gene set enrichment, expression and survival analyses on human breast cancer brain metastases.ResultsWe found ROR2 to be highly expressed in aggressive breast tumors and associated with worse metastasis-free survival. ROR2 overexpression induced a BRCAness-like phenotype in a cell-context specific manner and rendered cells resistant to PARP inhibition. High levels of ROR2 were furthermore associated with defects in cell morphology and cell-cell-contacts leading to increased tumor invasiveness. On a molecular level, ROR2 overexpression upregulated several non-canonical WNT ligands, in particular WNT11. Co-immunoprecipitation confirmed that WNT11 indeed interacts with the cysteine-rich domain of ROR2 and triggers its invasion-promoting signaling via RHO/ROCK. Knockdown of WNT11 reversed the pro-invasive phenotype and the cellular changes in ROR2-overexpressing cells.ConclusionsTaken together, our study revealed a novel auto-stimulatory loop in which ROR2 triggers the expression of its own ligand, WNT11, resulting in enhanced tumor invasion associated with breast cancer metastasis.

Primaquine Inhibits the Endosomal Trafficking and Nuclear Localization of EGFR and Induces the Apoptosis of Breast Cancer Cells by Nuclear EGFR/Stat3-Mediated c-Myc Downregulation.

Triple-negative breast cancer (TNBC) cells overexpress the epidermal growth factor receptor (EGFR). Nuclear EGFR (nEGFR) drives resistance to anti-EGFR therapy and is correlated with poor survival in breast cancer. Inhibition of EGFR nuclear translocation may be a reasonable approach for the treatment of TNBC. The anti-malarial drugs chloroquine and primaquine have been shown to promote an anticancer effect. The aim of the present study was to investigate the effect and mechanism of chloroquine- and primaquine-induced apoptosis of breast cancer cells. We showed that primaquine, a malaria drug, inhibits the growth, migration, and colony formation of breast cancer cells in vitro, and inhibits tumor growth in vivo. Primaquine induces damage to early endosomes and inhibits the nuclear translocation of EGFR. Primaquine inhibits the interaction of Stat3 and nEGFR and reduces the transcript and protein levels of c-Myc. Moreover, primaquine and chloroquine induce the apoptosis of breast cancer cells through c-Myc/Bcl-2 downregulation, induce early endosome damage and reduce nEGFR levels, and induce apoptosis in breast cancer through nEGFR/Stat3-dependent c-Myc downregulation. Our study of primaquine and chloroquine provides a rationale for targeting EGFR signaling components in the treatment of breast cancer.

High GNG13 expression is associated with poor survival in epithelial ovarian cancer and breast cancer.

Recently, change in the GNG13 expression has been shown to result in multiple congenital malformations and sexual reversal, and it was also found in the brain. The aim of this study was to measure the expression levels in epithelial ovarian cancer (EOC) and breast cancer (BC) and assess their value as a potential prognostic marker. The correlation of GNG13 protein expression was detected by immunohistochemistry (IHC) in 119 EOC and 125 BC tissues. Assessment of the associations between GNG13 levels and various clinicopathological features was identified, the relationship between GNG13 and prognosis in BC and EOC patients was analyzed using online resources of Oncomine and Kaplan-Meier plotter. Protein expression levels of GNG13 were both significantly lower in BC and EOC compared with normal tissues (p<0.0001 and p<0.001, respectively). Among the clinicopathological characteristics of BC, tumor grade (p=0.001) and TNM stage (p=0.001) were significantly associated with low expression of GNG13. While in EOC, low expression of GNG13 was significantly related to FIGO stage (p=0.001), presence of metastasis (p=0.001), and CA125 (p=0.001). Our data suggest that GNG13 expression maybe as a new inhibitor, which can strongly inhibit metastasis and partially attenuates tumor growth in EOC and BC.

MiR-98-5p/IGF2 Axis Influence Herceptin Sensitivity through IGF1R/HER2 Heterodimer Formation and AKT/mTOR Signal Pathway in HER2 Positive Breast Cancer.

Background and Aim:IGF1R and HER2 are both members of the growth factor receptor family which is known to play a different role in breast cancer. However, correlation between IGF1R and HER2 has created a controversial situation that need to be fully delineated in development of Herceptin resistance. The aim of this study was to investigate the mechanism of Herceptin resistance through the IGF1R pathway in HER2 positive breast cancer. Materials and Methods:Clinical data were obtained from TCGA database and archived documents from The First Affiliated Hospital of Bengbu Medical College. Western blot and immunohistochemistry were used to detect proteins and their phosphorylation. Cell transfection were constructed using shRNA lentivirus vectors. RNAs were analyzed by RT-qPCR. Proteins in serum were analyzed by ELISA assay. Cell proliferation was analyzed by MTS method. Luciferase report experiment was conducted to verify RNA’s inter-reaction. Results:Western blot showed IGF2 protein was significantly increased in Herceptin resistant SKBR3-R cells (P<0.01), and IGF1R/HER2 heterodimer level was significantly increased (P<0.01). Luciferase reporter assay verified miR-98-5p could bind to 3 ‘UTR of IGF2 mRNA. When miR-98-5p was upregulated, the expression level of IGF2 was decreased(P<0.01), the cell invasive ability was reduced(P<0.01), and ultimately, Herceptin resistant cells regained their sensitivity to Herceptin. In clinical research, we found that decreased miR-98-5p level or increased IGF2 level significantly associated with poor treatment response and poor overall survival (OS), poor recurrence free survival (RFS) and poor distant metastasis-free survival (DMFS) in HER2-positive breast cancer. Conclusion: MiR-98-5p and IGF2 might potential candidates for predicting Herceptin sensitivity and provides a new way to overcome Herceptin resistance in clinic.

High Cell-Free DNA Integrity Is Associated with Poor Breast Cancer Survival.

Simple SummaryA recent point of focus in breast cancer (BC) research has been the utilization of cell-free DNA and its concentration (cfDConc) and integrity (cfDI) as potential biomarkers. Though the association of cfDConc and BC survival is already recognized, studies on the prognostic value of cfDI have had contradictory results. The aim of this study was to investigate the prognostic potential of cfDConc and cfDI in Eastern Finnish BC cases with a non-metastatic disease. While the prognostic value of cfDConc remained non-significant in our analyses, high cfDI was an independent prognostic factor for poor overall survival (OS) and breast cancer-specific survival (BCSS). Inclusion of cfDI in the multivariate logistic regression model improved the predictive performance of the model, thus suggesting that the combined use of traditional tumor features and liquid biopsy could help to discriminate BC patients with poor OS and BCSS more accurately at the time of diagnosis.Background: A recent point of focus in breast cancer (BC) research has been the utilization of cell-free DNA (cfDNA) and its concentration (cfDConc) and integrity (cfDI) as potential biomarkers. Though the association of cfDConc and poor survival is already recognized, studies on the prognostic value of cfDI have had contradictory results. Here, we provide further evidence to support the use of cfDI as a potential biomarker. Methods: We selected 204 Eastern Finnish BC cases with non-metastatic disease and isolated cfDNA from the serum collected at the time of diagnosis before any treatment was given. The cfDConc and cfDI were measured with a fluorometer and electrophoresis and analyzed with 25 years of survival data. Results: High cfDConc was not an independent prognostic factor in our analyses while high cfDI was found to be an independent prognostic factor for poor OS (p = 0.020, hazard ratio (HR) = 1.57, 95% confidence interval (CI) 1.07–2.29, Cox) and BCSS (p = 0.006, HR = 1.93, 95% CI 1.21–3.08)). Inclusion of cfDI in the multivariate logistic regression model improved the predictive performance. Conclusions: Our results show high cfDI is an independent prognostic factor for poor OS and BCSS and improves the predictive performance of logistic regression models, thus supporting its prognostic potential.

Abstract 2172: Proteogenomics of laser microdissected difficult-to-treat breast cancers identifies Basal and Her2 patients associated with outcome differences

Abstract Introduction: Breast cancer (BC) is the second most common cause of cancer death among women in the USA. Recent proteogenomic studies of human BC have identified many potential therapeutic biomarkers for the most common types of BC. Here, we strive to comprehensively understand the proteogenomic landscape of difficult-to-treat breast cancer (DTBC) tumors. Methods: 118 primary breast tumors, with a focus on DTBC patients, were selected from the IRB-approved protocol. The study cohort included 30 triple negative, 16 HER2+, 16 Luminal A, 39 Luminal B1, and 17 Luminal B2 selected by immunohistochemistry. Breast tumors were embedded in OCT (Optimum Cutting Temperature) and processed by laser microdissection (LMD) to remove non-tumorous tissue. DNA, RNA, and protein were simultaneously extracted from each tumor using the illustra triplePrep kit. Paired-end RNA sequencing and whole genome sequencing (WGS) were performed for 118 and 100 tumors, respectively, using the Illumina HiSeq platform. Quantitative global proteomics and phosphoproteomic analyses were performed on 113 and 50 tumors, respectively, using isobaric TMT 6-plex labeling with the “universal reference” strategy. Results: Unlike other BC cohorts, our WGS cohort had an almost equal number of Estrogen(ER)+ (55.6%) and ER- (44.4%) cases, which gave us a nominally higher percentage TP53 (57%) and lower PIK3CA (32%) non-silent somatic mutation. Similar to previous reports, GATA3 was mutated in 13% of only ER+ cases. Unlike a recent report on proteomics clustering of bulk-processed tumors, our data show that a stromal-enriched cluster was not mixed with all subtypes but a majority of Luminal A (LumA) subtype, probably because LMD excluded stromal components in other tumor subtypes. Consensus clustering of proteomics data separated intrinsic Her2 patients with outcome differences. Her2 patients associated with the Basal-enriched proteome cluster had better survival than those associated with the LumA-enriched proteome cluster. Previously reported marker PGK1, a predictor for poor survival in BC, was upregulated in Her2 tumors associated with the LumA-enriched proteome cluster. The clustering of phosphoproteomics data separated intrinsic Basal patients into groups with and without relapse. We identified 3 and 18 genes with upregulated kinase activities in the relapse-free and relapsed Basal patients, respectively. In conclusion, this study provides a high-quality proteogenomic resource for DTBC investigation and identifies potential molecular markers for predicting outcomes for patients with less responsive tumors. The views expressed in this abstract are solely of the authors and do not reflect the official policy of the Departments of Army/Navy/Air Force, DoD, USUHS, HJF. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. Government. Citation Format: Praveen-Kumar Raj-Kumar, Tao Liu, Lori A. Sturtz, Albert J. Kovatich, Marina A. Gritsenko, Vladislav A. Petyuk, Brenda Deyarmin, Jianfang Liu, Anupama Praveen-Kumar, Jason E. McDermott, Anil K. Shukla, Ronald J. Moore, Matthew E. Monroe, Bobbie-Jo M. Webb-Robertson, Jeffrey A. Hooke, Leigh Fantacone-Campbell, Leonid Kvecher, Jennifer Kane, Jennifer Melley, Stella Somiari, Stephen C. Benz, Justin Golovato, Shahrooz Rabizadeh, Patrick Soon-Shiong, Richard D. Smith, Richard J. Mural, Karin D. Rodland, Craig D. Shriver, Zhaoyu Li, Hai Hu. Proteogenomics of laser microdissected difficult-to-treat breast cancers identifies Basal and Her2 patients associated with outcome differences [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2172.

Mortgage Lending Bias and Breast Cancer Survival Among Older Women in the United States.

The objective was to examine the relationship between contemporary redlining (mortgage lending bias on the basis of property location) and survival among older women with breast cancer in the United States. A redlining index using Home Mortgage Disclosure Act data (2007-2013) was linked by census tract with a SEER-Medicare cohort of 27,516 women age 66-90 years with an initial diagnosis of stage I-IV breast cancer in 2007-2009 and follow-up through 2015. Cox proportional hazards models were used to examine the relationship between redlining and both all-cause and breast cancer-specific mortality, accounting for covariates. Overall, 34% of non-Hispanic White, 57% of Hispanic, and 79% of non-Hispanic Black individuals lived in redlined tracts. As the redlining index increased, women experienced poorer survival. This effect was strongest for women with no comorbid conditions, who comprised 54% of the sample. For redlining index values of 1 (low), 2 (moderate), and 3 (high), as compared with 0.5 (least), hazard ratios (HRs) (and 95% CIs) for all-cause mortality were HR = 1.10 (1.06 to 1.14), HR = 1.27 (1.17 to 1.38), and HR = 1.39 (1.25 to 1.55), respectively, among women with no comorbidities. A similar pattern was found for breast cancer-specific mortality. Contemporary redlining is associated with poorer breast cancer survival. The impact of this bias is emphasized by the pronounced effect even among women with health insurance (Medicare) and no comorbid conditions. The magnitude of this neighborhood level effect demands an increased focus on upstream determinants of health to support comprehensive patient care. The housing sector actively reveals structural racism and economic disinvestment and is an actionable policy target to mitigate adverse upstream health determinants for the benefit of patients with cancer.

The Ferroxidase Hephaestin in Lung Cancer: Pathological Significance and Prognostic Value.

Hephaestin (HEPH) belongs to a group of exocytoplasmic ferroxidases which contribute to cellular iron homeostasis by favouring its export. Down-regulation of HEPH expression, possibly by stimulating cell proliferation due to an increase in iron availability, has shown to correlate with poor survival in breast cancer. The lung is particularly sensitive to iron-induced oxidative stress, given the high oxygen tension present, however, HEPH distribution in lung cancer and its influence on prognosis have not been investigated yet. In this study we explored the prognostic value of HEPH and its expression pattern in the most prevalent histotypes of lung cancers, namely lung adenocarcinoma and lung squamous cell carcinoma. In silico analyses, based on UALCAN, Gene Expression Profiling Interactive Analysis (GEPIA) and Kaplan–Meier plotter bioinformatics, revealed a significant correlation between higher levels of HEPH expression and favorable prognosis, in both cancer histotypes. Moreover, TIMER web platform showed a statistically significant association between HEPH expression and cell elements belonging to the tumor microenvironment identified as endothelial cells and a subpopulation of cancer-associated fibroblasts, further confirmed by double immunohistochemical labeling with cell type specific markers. Taken together, these data shed a light on the complex mechanisms of local iron handling lung cancer can exploit to support tumorigenesis.

136P The incidence and prognostic impact of obesity in young Egyptian breast cancer patients

The breast cancer (BC) incidence of young women in Africa and the Middle East is higher than that of the western population. Growing evidence shows a global increase in obesity incidence. Both obesity and young age are associated with poor survival in BC. Thus, it is relevant to address this question in this population. We retrospectively reviewed 720 female BC patients ≤40 years who had the weight and height data in two centers in Alexandria – Egypt. The body mass index (BMI) was categorized according to WHO groups into underweight – UW (BMI 18.5 kg/m2), normal weight - NW (BMI ≥18.5 to < 25kg/m2), overweight – OW (BMI ≥25 to < 30kg/m2), obese – Ob (BMI >30 kg/m2). We determined the obesity incidence, clinicopathological features, and the impact of obesity on survival by Kaplan Meir and Cox regression. The median follow-up was 44 months (1 - 143). The BMI distribution was UW - 1.7% (12), NW - 11.1% (80), OW - 26.8% (193), Ob - 60.4% (435); more than 85% were Ob/OW. The median age in UW/NW, OW, and Ob was 34, 35, and 37 years, respectively. Ob patients were significantly older, p < 0.001. The mean tumor size was 3.4cm in UW/NW, 3.7cm – OW, and 3.7cm - Ob. The Ob had a significantly higher incidence of high nodal involvement (44%; p − 0.023), and significantly estrogen/progesterone negative (21.2%; p − 0.016). Ki-67 was higher in Ob (57.4%) and OW (74%) than UW/NW (50%); p – 0.222. The distant relapse rates were insignificantly higher in Ob - 25.7% and OW - 25.5% than UW/NW - 20.2%; p – 0.352. There were no significant differences in the mean disease-free survival (CI: 81 – 96; p-0.692) and the overall survival (CI:120 – 124; p-0.186). In the multivariate analysis and cox regression, obesity did not impact survival. There is an alarmingly high incidence of Ob/OW among young Egyptian BC patients. Our results confirm that Ob patients have more aggressive features than UW/NW. Nevertheless, our results suggest that, despite the poor prognostic factors characteristics, higher BMI did not worsen the survivals.

Breast adipose tissue macrophages (BATMs) have a stronger correlation with breast cancer survival than breast tumor stroma macrophages (BTSMs)

BackgroundAn abundance of tumor-associated macrophages has been shown to be an independent prognostic factor for a poor prognosis of human breast cancer (BC). Adipose tissue accounts for the largest proportion of the breast and has also been identified as an independent indicator of poor survival in BC. This study aims to elucidate if the influence of adipose tissue in BC might be mediated by macrophages. The roles of macrophages in the breast tumor-stroma (breast tumor stroma macrophages, BTSM) and macrophages in the surrounding adipose tissue (breast adipose tissue macrophages, BATM) were explored separately.MethodsTwo hundred ninety-eight BC tissue samples were analyzed immunohistochemically. The number of macrophages was detected by CD68+ staining. The quantity of BATMs and BTSMs was correlated to clinical and pathological parameters as well as to disease-free survival (DFS) and overall survival (OS).ResultsThe amounts of BATMs and BTSMs strongly correlated with each other (r = 0.5, p = 2.98E−15). The quantity of BTSMs, but not of BATMs, was significantly associated with the BC molecular subtype (p = 0.000011), and all triple-negative BC tumors contained high amounts of BTSMs. BATMs were negatively associated with DFS (p = 0.0332). Both BATMs (p = 0.000401) and BTSMs (p = 0.021) were negatively associated with OS in the Kaplan-Meier analysis, but only BATMs remained an independent factor in the multivariate Cox-regression analysis (HR = 4.464, p = 0.004). Combining prostaglandin E2 receptor 3 (EP3)-expression and the quantity of BATMs, a subgroup with an extremely poor prognosis could be identified (median OS 2.31 years in the “high BATMs/low EP3” subgroup compared to 11.42 years in the most favorable “low BATMs/high EP3” subgroup, p = 0.000002).ConclusionOur findings suggest that BTSMs and BATMs seem to be involved differently in BC. Breast adipose tissue might contribute to the aggressiveness of BC via BATMs, which were independently associated with BC survival. BATMs’ role and occurrence might be functionally dependent on EP3, as a combination of both factors was strongly associated with survival. Targeting BATMs—eventually in combination with targeting the EP3-pathway—might be promising for future therapies.

Diverse and converging roles of ERK1/2 and ERK5 pathways on mesenchymal to epithelial transition in breast cancer

The epithelial to mesenchymal transition (EMT) is characterized by a loss of cell polarity, a decrease in the epithelial cell marker E-cadherin, and an increase in mesenchymal markers including the zinc-finger E-box binding homeobox (ZEB1). The EMT is also associated with an increase in cell migration and anchorage-independent growth. Induction of a reversal of the EMT, a mesenchymal to epithelial transition (MET), is an emerging strategy being explored to attenuate the metastatic potential of aggressive cancer types, such as triple-negative breast cancers (TNBCs) and tamoxifen-resistant (TAMR) ER-positive breast cancers, which have a mesenchymal phenotype. Patients with these aggressive cancers have poor prognoses, quick relapse, and resistance to most chemotherapeutic drugs. Overexpression of extracellular signal-regulated kinase (ERK) 1/2 and ERK5 is associated with poor patient survival in breast cancer. Moreover, TNBC and tamoxifen resistant cancers are unresponsive to most targeted clinical therapies and there is a dire need for alternative therapies.In the current study, we found that MAPK3, MAPK1, and MAPK7 gene expression correlated with EMT markers and poor overall survival in breast cancer patients using publicly available datasets. The effect of ERK1/2 and ERK5 pathway inhibition on MET was evaluated in MDA-MB-231, BT-549 TNBC cells, and tamoxifen-resistant MCF-7 breast cancer cells. Moreover, TU-BcX-4IC patient-derived primary TNBC cells were included to enhance the translational relevance of our study. We evaluated the effect of pharmacological inhibitors and lentivirus-induced activation or inhibition of the MEK1/2-ERK1/2 and MEK5-ERK5 pathways on cell morphology, E-cadherin, vimentin and ZEB1 expression. Additionally, the effects of pharmacological inhibition of trametinib and XMD8-92 on nuclear localization of ERK1/2 and ERK5, cell migration, proliferation, and spheroid formation were evaluated. Novel compounds that target the MEK1/2 and MEK5 pathways were used in combination with the AKT inhibitor ipatasertib to understand cell-specific responses to kinase inhibition. The results from this study will aid in the design of innovative therapeutic strategies that target cancer metastases.