Triple-negative Breast Cancer Patients Research Articles

PTPN20 promotes metastasis through activating NF-κB signaling in triple-negative breast cancer.

Cancer metastasis remains a major challenge in the clinical management of triple-negative breast cancer (TNBC). The NF-κB signaling pathway has been implicated as a crucial factor in the development of metastases, but the underlying molecular mechanisms remain largely unclear. PTPN20 expression was evaluated using data from the Sweden Cancerome Analysis Network-Breast and The Cancer Genome Atlas database, as well as by western blotting and immunohistochemistry in 88 TNBC patients. The ability of PTPN20 to activate NF-κB was assessed by luciferase reporter assays. The effects of PTPN20 overexpression and knockdown via short hairpin RNA were examined in TNBC cell lines by wound healing and transwell matrix penetration assays. Additionally, we analyzed the growth and metastasis abilitiy of 4T1 xenograft tumors in nude mice. PTPN20 levels were elevated in TNBC cell lines and patient samples compared to controls, and higher protein levels correlated with metastasis-free survival. Overexpression of PTPN20 enhanced migration and invasion in vitro, and promoted lung metastasis in vivo. Our finding revealed that PTPN20 activates NF-κB signaling by dephosphorylating p65 at Ser468, preventing its binding to COMMD1, thereby protecting p65 from degradation. Downregulation of PTPN20 effectively inhibit, while p65 S468A mutant restored the migratory and invasive abilities of TNBC cells. Collectively, our results demonstrate that PTPN20 plays a critical role in TNBC metastasis through the activation of NF-κB signaling. We propose that PTPN20 may serve as a novel prognostic marker and potential therapeutic target for the treatment of TNBC.

Glucocorticoid Receptor Isoforms in Breast Cancer Raise Implications for Personalised Supportive Therapies

Glucocorticoid receptor (GR) activation may promote metastasis in oestrogen receptor-negative and triple-negative breast cancer (TNBC). However, the role of the GRβ isoform, which has opposing effects to the main isoform, has not been studied in clinical samples. We aimed to analyse the intracellular localisation of total GR and GRβ in vitro using plasmid constructs and fluorescent immunocytochemistry. Additionally, our goal was to perform immunostaining for total GR and GRβ on two cohorts: (i) on 194 clinical breast cancer samples to compare the expression in different molecular subtypes, and (ii) on 161 TNBC samples to analyse the association of GR with survival. We supplemented our analysis with RNA data from 1097 TNBC cases. We found that in the absence of the ligand, GR resided in the cytoplasm of breast cancer cells, while upon ligand activation, it translocated to the nucleus. A negative correlation was found between cytoplasmic GRtotal and Ki67 in luminal A tumours, while the opposite trend was observed in TNBC samples. Tumours with strong lymphoid infiltration showed higher cytoplasmic GRtotal staining compared to those with weaker infiltration. Patients with high nuclear GRtotal staining had shorter progression-free survival in univariate analysis. High cytoplasmic GRβ was a marker for better overall survival in multivariate analysis (10-year overall survival HR [95% CI]: 0.46 [0.22–0.95], p = 0.036). As a conclusions, this study is the first to investigate GRβ expression in breast tumours. Different expression and cellular localisation of GRtotal and GRβ were observed in the context of molecular subtypes, underscoring the complex role of GR in breast cancer. An inverse association between cytoplasmic GRtotal and the Ki67 proliferation index was observed in luminal A and TNBC. Regarding the impact of GR on outcomes in TNBC patients, while cytoplasmic GRβ was associated with a better prognosis, patients with nuclear GRtotal staining may be at a higher risk of disease progression, as it negatively affects survival. Caution should be exercised when using glucocorticoids in patients with nuclear GR staining, as it may negatively impact survival.

Clinical Significance of FAM83G in Breast Cancer: Association With Triple-negative Subtype and Prognosis.

Family with sequence similarity 83 member G (FAM83G) plays an important role in cancer aggressiveness and patients' prognosis across various types of cancer. However, the association of FAM83G protein expression in breast cancer with clinicopathologic factors, breast cancer subtypes, and prognosis is not well characterized. This study aimed to elucidate the clinical significance of FAM83G protein expression in breast cancer. Immunohistochemistry was employed to examine FAM83G protein expression in 75 breast cancer tissues, assessing its potential as a biomarker for breast cancer patients. The Kaplan-Meier plotter was used to estimate the correlation between FAM83G mRNA expression and survival outcomes in TNBC patients. FAM83G protein was predominantly localized in the cytoplasm of breast cancer cells, exhibiting uniform expression throughout tumor tissues. FAM83G expression was significantly higher in cancerous areas compared to non-cancerous areas. High FAM83G expression was more prevalent in triple-negative breast cancer (TNBC) cases than in hormone receptor-positive cases. Although high FAM83G protein expression did not significantly impact prognosis in our cohort, a large-scale database analysis revealed an association between high FAM83G expression and poor prognosis in TNBC cases. This study demonstrates an association between high FAM83G expression in breast cancer tissues and TNBC. FAM83G may serve as a promising biomarker and therapeutic target for breast cancer patients.

Leveraging chemotherapy-induced PD-L1 upregulation to potentiate targeted PD-L1 degradation using nanoparticle-based targeting chimeras

The combination of nab-paclitaxel and the programmed death-ligand 1(PD-L1) antibody atezolizumab showed limited benefits in clinical trials involving PD-L1-positive triple-negative breast cancer patients. This observed lack of success is attributed to the upregulation of PD-L1 on tumor cells induced by paclitaxel, leading to resistance against PD-L1 antibodies. Here, we introduce nanoparticle-based PD-L1 targeting chimeras (NanoTACPD-L1) to induce PD-L1 degradation instead of blockade. NanoTACPD-L1 initiates endocytosis independent of specific lysosome-targeting receptors, and delivers membrane-bound PD-L1 to lysosomes for targeted degradation. Furthermore, the efficiency of degradation is directly correlated with the PD-L1 expression level. NanoTACPD-L1 effectively leverages paclitaxel-induced PD-L1 upregulation to enhance PD-L1 degradation, employing a “Meet-Plot-With-Plot” strategy. In a series of in vivo models, NanoTACPD-L1 demonstrates superior therapeutic efficacy and immune activation, both when administered individually and in combination with paclitaxel, surpassing the effects of anti-PD-L1 antibody treatment. Collectively, our study provides a nanotechnology-based tool that can be enhanced by paclitaxel for PD-L1 degradation and validates its potential application in overcoming chemo-immunotherapy resistance.

Comparison of the Predictive and Prognostic Capacities of Neutrophil, Lymphocyte and Platelet Counts and Tumor-infiltrating Lymphocytes in Triple-negative Breast Cancer: Preliminary Results of the PERCEPTION Study.

Triple-negative breast cancer (TNBC) is the most heterogeneous breast cancer subtype, posing numerous challenges in clinical decision-making. Biomarkers are essential to personalize management of TNBC patients. While tumor infiltrating lymphocytes (TILs) are validated prognostic biomarkers, the requirement for tumor biopsy limits their routine use. Therefore, more accessible and reliable quantitative biomarkers are needed. Given the significant role of systemic inflammatory response in tumor onset and progression, assessing inflammatory cells via liquid biopsies emerges as a promising alternative. The PERCEPTION study, conducted at Centre Jean Perrin in France, aims to determine the correlation between TILs and peripheral blood components at diagnosis. An interim analysis was conducted after enrolling 50% of the estimated population, to evaluate study feasibility and preliminary correlations between blood cell counts and TILs. Sixty-one patients were enrolled over 4.5 years, demonstrating a good inclusion rate with minimal missing data. Preliminary results for 36 analyzable patients showed no correlation between the neutrophil-to-lymphocyte ratio (NLR) and TILs (rs=-0.19, 95%CI=-0.49-0.16, p=0.3). However, a moderate, positive, statistically significant correlation was found between NLR and the CD8/FoxP3 TILs ratio (rs=0.36, 95%CI=0.03-0.64, p=0.043). The probabilistic index of 0.7 (p=0.06) between NLR-high and NLR-low groups for this ratio supports the correlation. The interim analysis of the PERCEPTION study confirms the feasibility of correlating blood cell counts with TILs in TNBC. Although no significant correlation was observed between NLR and TILs, the moderate positive correlation between the CD8/FoxP3 ratio and TILs suggests a potential link between systemic inflammation and local immune response. These findings underscore the potential of blood-based markers as non-invasive surrogates for TILs, encouraging further research to enhance prognosis and guide treatment strategies in TNBC.

Olaparib monotherapy in advanced triple-negative breast cancer patients with homologous recombination deficiency and without germline mutations in BRCA1/2: the NOBROLA phase 2 study

Olaparib monotherapy in advanced triple-negative breast cancer patients with homologous recombination deficiency and without germline mutations in BRCA1/2: the NOBROLA phase 2 study

Impact of the CPS-EG score as a new prognostic biomarker in triple-negative breast cancer patients who received neoadjuvant chemotherapy

BackgroundThis study aimed to establish risk groups on the basis of CPS-EG scores, independent of pCR status, in triple-negative breast cancer (TNBC) patients receiving neoadjuvant chemotherapy (NACT) to identify the prognostic impact of the CPS-EG score.MethodsPatient characteristics included age, menopausal status, clinical stage, pathological stage, estrogen receptor (ER) expression, nuclear grade, Ki-67 proliferation index, residual cancer burden (RCB) score, HER2 status, and other tumor characteristics. The CPS-EG scoring system included clinical stage, pathological stage, ER status, and grade. Patients were divided into two groups on the basis of their CPS-EG scores ≤ 3 and > 3.ResultsA total of 148 patients who were diagnosed with TNBC and treated with NACT were included in the study. A total of 52.0% of the patients had a CPS-EG score of ≤ 3, whereas 48.0% had a score of > 3. The rate of patients who achieved pCR was 29.7% (n = 44). CPS-EG score (HR: 2.331; 95%CI; 1.179–4.608; p = 0.015), pCR (HR: 0.348; 95%CI; 0.144–0.844; p = 0.019), pre-treatment mKi-67 proliferation index (HR: 0.467; 95%CI; 0.251–0.871; p = 0.017), and RCB score (HR: 0.401; 95%CI; 0.174–0.923; p = 0.032) were identified as significant prognostic factors for 5-year DFS. For 5-year OS, significant prognostic factors were CPS-EG score (HR: 2.30; 95%CI; 1.036–4.799; p = 0.040) and pre-treatment mKi-67 proliferation index (HR: 0.484; 95%CI; 0.246–0.954; p = 0.036).ConclusionsThe CPS-EG score, pre-treatment mKi-67 level, and the pCR and RCB score were practical prognostic markers for long-term survival. Conversely, the prognostic significance of pCR status was diminished, particularly in predicting OS. These findings underscore the importance of not only post-treatment pathological staging but also the initial tumor stage and biological characteristics of the tumor in predicting ultimate survival outcomes following neoadjuvant chemotherapy in TNBC patients.

The lncRNA AFAP1-AS1 is upregulated in metastatic triple-negative breast tumors and controls hypoxia-activated vasculogenic mimicry and angiogenesis

BackgroundVasculogenic mimicry (VM) is an alternative intratumoral microcirculation system that depends on the capacity of tumor cells to reorganize and grow in three-dimensional (3D) channel architectures like the capillaries formed by endothelial cells. Both VM and angiogenesis may coordinately function to feed cancer cells, allowing tumor growth. Long noncoding RNAs (lncRNAs) regulate critical cellular functions in cancer cells, including cell proliferation, apoptosis, angiogenesis, invasion, and metastasis. The lncRNA, known as actin filament-associated protein 1-antisense RNA 1 (AFAP1-AS1), has been described as an oncogene in diverse types of cancers. However, its role in VM and metastasis in triple-negative breast cancer (TNBC) is unknown.MethodsReverse transcription and quantitative polymerase chain reaction (RT‒qPCR) experiments were performed to evaluate the expression of 10 selected lncRNAs from literature in metastatic and nonmetastatic biopsies from TNBC patients. The expression of AFAP1-AS1 was analyzed in Genotype-Tissue Expression Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) datasets. The AFAP1-AS1 expression was knocked in TNBC Hs578T cells by transfection of specific siRNAs. Channel-like formation assays were performed using 3D cultures over Matrigel in hypoxia-treated Hs578T cancer cells with diminished expression of AFAP1-AS1. The angiogenesis tests were conducted using human umbilical vein endothelial cells (HUVECs) and AFAP1-AS1- silenced Hs578T cells on 3D cell cultures. The presence of VM (CD31-/PAS+) in tumor tissues from TNBC patients with and without metastasis was assessed through immunohistochemistry using endothelial marker CD31 antibodies and periodic acid-Schiff (PAS) staining.ResultsCompared with normal mammary tissues, AFAP1-AS1 expression was higher in breast cancer tissues. Moreover, AFAP1-AS1 expression was upregulated in the TNBC subtype compared to receptor-positive breast tumors. In addition, the expression of AFAP1-AS1 was correlated with the expression of the thirteen genes characteristic of a previously reported hypoxia signature. Interestingly, AFAP1-AS1 was upregulated in primary TNBC tumors from patients who developed metastasis compared with the nonmetastatic group. Functional analysis revealed that the knockdown of AFAP1-AS1 in Hs578T cells significantly impaired the hypoxia-induced VM, accompanied by a decrease in the development of 3D channel networks. Similarly, AFAP1-AS1 knockdown counteracts the angiogenic potential of cancer cells, as indicated by a reduction in the number of polygons, sprouting cells, and nodes in HUVEC cells. Remarkably, an increase in CD31-/PAS + staining of 3D channel networks in primary breast tumors from metastatic patients was found compared with the nonmetastatic group. Finally, we found that the number of blood vessels increased in the nonmetastatic group more than in the metastatic cohort.ConclusionsOur data suggested that AFAP1-AS1 controls both VM and angiogenesis in Hs578T breast cancer cells and that increased metastasis is associated with VM in TNBC patients.

Expression of CD44 in Triple Negative Breast Cancer and its Correlation with Prognostic Parameters

Background: The study aims to evaluate CD44 expression as a cancer stem cell marker in Triple-negative breast cancer (TNBC) and its correlation with prognostic parameters. Evaluation of CD44 immunoexpression in TNBC is vital for understanding tumour aggressiveness and determining its prognostic value. Methods: A hospital based cross sectional study of 50 cases of primary triple negative breast cancer patients. The tissue sections were subjected to immunohistochemical examination using CD44 antigen marker. The proportion and intensity of CD44 immunostaining was assessed and correlation with prognostic markers such as histological grade, tumor size and nodal status. Results: CD44 expression was observed in 40% of the total cases with a statistically significant association with histological grade (p-value= 0.002). Higher CD44 expression was noticed with increasing tumour grade. However, no statistical significance was observed with respect to tumour size and nodal status. Conclusion: The study suggests that CD44 immunoexpression may serve as a surrogate marker of BCSCs and may hold prognostic value in TNBC patients. However, further studies on larger samples are required to fully understand its role.

Deciphering the landscape of triple negative breast cancer from microenvironment dynamics and molecular insights to biomarker analysis and therapeutic modalities.

Triple negative breast cancer (TNBC) displays a notable challenge in clinical oncology due to its invasive nature which is attributed to the absence of progesterone receptor (PR), estrogen receptor (ER), and human epidermal growth factor receptor (HER-2). The heterogenous tumor microenvironment (TME) of TNBC is composed of diverse constituents that intricately interact to evade immune response and facilitate cancer progression and metastasis. Based on molecular gene expression, TNBC is classified into four molecular subtypes: basal-like (BL1 and BL2), luminal androgen receptor (LAR), immunomodulatory (IM), and mesenchymal. TNBC is an aggressive histological variant with adverse prognosis and poor therapeutic response. The lack of response in most of the TNBC patients could be attributed to the heterogeneity of the disease, highlighting the need for more effective treatments and reliable prognostic biomarkers. Targeting certain signaling pathways and their components has emerged as a promising therapeutic strategy for improving patient outcomes. In this review, we have summarized the interactions among various components of the dynamic TME in TNBC and discussed the classification of its molecular subtypes. Moreover, the purpose of this review is to compile and provide an overview of the most recent data about recently discovered novel TNBC biomarkers and targeted therapeutics that have proven successful in treating metastatic TNBC. The emergence of novel therapeutic strategies such as chemoimmunotherapy, chimeric antigen receptor (CAR)-T cells-based immunotherapy, phytometabolites-mediated natural therapy, photodynamic and photothermal approaches have made a significant positive impact and have paved the way for more effective interventions.

Development and validation of a gene expression-based Breast Cancer Purity Score

The prevalence of malignant cells in clinical specimens, or tumour purity, is affected by both intrinsic biological factors and extrinsic sampling bias. Molecular characterization of large clinical cohorts is typically performed on bulk samples; data analysis and interpretation can be biased by tumour purity variability. Transcription-based strategies to estimate tumour purity have been proposed, but no breast cancer specific method is available yet. We interrogated over 6000 expression profiles from 10 breast cancer datasets to develop and validate a 9-gene Breast Cancer Purity Score (BCPS). BCPS outperformed existing methods for estimating tumour content. Adjusting transcriptomic profiles using the BCPS reduces sampling bias and aids data interpretation. BCPS-estimated tumour purity improved prognostication in luminal breast cancer, correlated with pathologic complete response in on-treatment biopsies from triple-negative breast cancer patients undergoing neoadjuvant treatment and effectively stratified the risk of relapse in HER2+ residual disease post-neoadjuvant treatment.

Real-World Outcomes with the KEYNOTE-522 Regimen in Early-Stage Triple-Negative Breast Cancer.

This study aimed to determine if the neoadjuvant (NAT) KEYNOTE-522 regimen was associated with higher rates of pathologic complete response (pCR), corresponding to higher rates of breast conservation therapy (BCT) in early-stage triple-negative breast cancer (TNBC) patients. Stage II-III TNBC patients diagnosed between 2019 and 2022 who underwent NAT were analyzed retrospectively. NAT with KEYNOTE-522 versus control NAT were compared for rates of BCT, axillary node dissection (ALND), pCR, and survival outcomes. The prevalence of immune-related adverse events (irAE) from chemoimmunotherapy was recorded. Of 240 patients identified: 86 received KEYNOTE-522 and 154 received control. The frequency of pCR was significantly higher in KEYNOTE versus the control cohort, 59.3% and 33.1%, respectively (p = 0.001). There was no significant difference in the rate of BCT between the control (33.1%) and the KEYNOTE-522 (32.1%) groups (p = 0.47). Rates of ALND were significantly lower with KEYNOTE-522 (25.6%) as compared with control (39.6%); p = 0.03. The rate of development of grade 2 or higher irAEs was 34.9%. At a median follow-up of 2.4 years, there was no difference in survival outcomes. BRCA1 patients had high rates of pCR regardless of treatment group, KEYNOTE-522: 80.0% (4/5) and control: 75% (9/12), (p = 1). This real-world evidence supports the use of the KEYNOTE-522 regimen in patients with early-stage TNBC given the higher pCR rate and corresponding decrease in the rate of ALND. The majority of patients in both NAT cohorts became BCT eligible, but the rate of BCT did not differ between the two groups.

Activation of the γ-secretase/NICD-PXR/Notch pathway induces Taxol resistance in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is currently the only subtype lacking efficient targeted therapies. Taxol is the primary chemotherapeutic agent for TNBC. However, Taxol resistance often develops in the treatment of TNBC patients, which importantly contributes to high mortality and poor prognosis in TNBC patients. Recent preclinical studies have shown that the inhibition of Notch pathway by γ-secretase inhibitors can slow down the progression of TNBC. Our studies in bioinformatic analysis of breast cancer patients and TNBC/Taxol cells in vitro showed that there was high correlation between the activation of Notch pathway and Taxol resistance in TNBC. Increased γ-secretase activity (by the overexpression of catalytic core PSEN-1) significantly reduced Taxol sensitivity of TNBC cells, and enhanced biological characteristics of malignancy in vitro, and tumour growth in vivo. Mechanistically, increased γ-secretase activity led to the accumulation of NICD in the nucleus, promoting the interaction between NICD and PXR to activate PXR, which triggered the transcription of PXR downstream associated drug resistance genes. Furthermore, we showed that pharmacological inhibition of γ-secretase with γ-secretase inhibitors (Nirogacestat and DAPT) can reverse Taxol resistance in vivo and in vitro. Our results for the first time demonstrate that the activation of γ −secretase/NCD-PXR/Notch pathway is one of important mechanisms to cause Taxol resistance in TNBC, and the blockades of this pathway may represent a new therapeutic strategy for overcoming Taxol resistance in TNBC.

Loss of WWOX contributes to cisplatin resistance in triple-negative breast cancer cells by modulating miR-182 and miR-214.

WW domain-containing oxidoreductase (WWOX) loss frequently occurs in triple-negative breast cancer (TNBC). WWOX loss enhances cisplatin resistance in TNBC patients. Although WWOX loss has an effect on the selection of a DNA repair pathway that contributes to enhanced mutagenesis, the downstream expression changes in resistant cancer cells have not been fully explored. This study aimed to investigate the potential role of microRNAs (miRNAs) in the regulation of cisplatin resistance in WWOX-deficient TNBC cells. Transient transfections were performed to overexpress WWOX in MDA-MB-231 cells. WWOX-overexpressing MDA-MB-231 cells were determined by western blot. Expression profiling of the miRNA was assessed via real-time polymerase chain reaction. miRNA expression profiling of WWOX-deficient and -sufficient MDA-MB-231 cells revealed that miR-182 upregulation and miR-214 downregulation were markedly positively associated with cisplatin resistance of WWOX-deficient MDA-MB-231 cells. An elevated expression of miR-182 and decreased expression of miR-214 may contribute to cisplatin resistance in WWOX-absent MDA-MB-231 cells by signaling pathway dysregulation of DNA repair/apoptosis/ protein kinase B (AKT). The results emphasize that WWOX deficiency promotes resistance to cisplatin in TNBC cells and the possible predicting biomarker of WWOX for resistance to cisplatin.

Histologic Characterization of Tumor-Adjacent Mammary Adipose Tissue in Normal-Weight and Overweight/Obese Patients with Triple-Negative Breast Cancer

Background: Obesity is a risk factor of several types of cancer, including breast cancer. In this study, we aimed to histologically characterize the adipose tissue of the tumor microenvironment (TME) of triple-negative breast cancer (TNBC) in overweight/obese versus normal-weight patients. Methods: TNBC tissue sections from normal-weight (BMI<25) and overweight/obese patients (BMI≥25) were stained with antibodies against CD68, CD163, CD31, CD34, and vimentin. At the invasive tumor front, positive cells were counted in tumor adjacent adipose tissue (AT) and within cancer tissue (CT). Further, the size of the tumor-adjacent and distant mammary adipocytes was determined in perilipin stained sections. Expression of ANGPTL4, CD36 and FABP4, proteins involved in fatty acid metabolism, was analyzed in marginal tumor cells using an immune reactive score. Results: Overweight/obese TNBC patients had significantly larger adipocytes, higher numbers of CD163+ macrophages (BMI<25: 2.80 vs. BMI≥25: 10.45; p = 0.011) and lower numbers of CD31+ (BMI<25: 4.20 vs. BMI≥25: 2.40; p = 0.018) and CD34+ (BMI<25: 14.60 vs. BMI≥25: 5.20; p = 0.045) cells as markers of angiogenesis in the AT as well as a higher frequency of cancer-associated-fibroblast-like cells in the AT and CT (BMI<25: 7.60 vs. BMI≥25: 25.39 in total; p = 0.001). Moreover, expression of CD36 (BMI<25: 2.15 vs. BMI≥25: 2.60; p = 0.041) and ANGPTL4 (BMI<25: 6.00 vs. BMI≥25: 9.80; p = 0.026) was elevated in the TNBC cells of overweight/obese patients. Conclusions: Our data suggest BMI-related changes in the TME of overweight/obese TNBC patients, including hypertrophied adipocytes, reduced vascularization, more M2-like macrophages and CAF-like cells, and an increase in the expression of fatty acid metabolizing proteins in marginal tumor cells, all contributing to a more tumor-promoting, immunosuppressive environment.

Differential Expression of Circulating miR-195 in a Sample of Iraqi Breast Cancer Patients Associations with Molecular Subtypes and Disease Stages

Breast cancer (BC) is a multifaceted disease characterized by different molecular subtypes and stages. MicroRNAs (miRNAs)are increasingly becoming recognized as valuable tools for predicting and identifying persons with BC, particularly miR-195. This study aimed to evaluate the expression of miR-195 in BC patients and its correlation with demographic and clinical parameters. The study involved 60 female BC patients and 60 healthy controls. Demographic analysis showed that 65% of BC patients have a family history of BC. Invasive ductal carcinoma (IDC) was the most prevalent type (85%), and luminal A was the most common molecular subtype (57%). The majority of cases were in stage II (40%) and stage III (36%), with patients primarily in the 40-59 age range (70%). RT-qPCR analysis revealed significant upregulation of miR-195 (6.752 ± 4.06-fold change) in BC patients compared to healthy controls. However, expression levels varied among molecular subtypes and stages. Triple-negative BC patients showed significant downregulation of miR-195 (0.45±0.3-fold change) compared to other subtypes. Similarly, stage IV patients exhibited significant downregulation (0.63±0.24-fold decrease) compared to earlier stages. Interestingly, no significant differences in miR-195 expression were observed among different BC types (IDC, ILC, and others). These findings suggest that miR-195 could potentially serve as a biomarker for BC, particularly in distinguishing molecular subtypes and advanced stages. However, further research is needed to validate its clinical utility and understand its role in BC progression and prognosis.

Retrospective evaluation of adjuvant capecitabine dosing patterns in triple negative breast cancer.

The CREATE-X trial demonstrated that adjuvant capecitabine was effective in prolonging survival in high-risk triple-negative breast cancer (TNBC) patients. However, the recommended dose is generally not well tolerated by the US population. The goal of this study is to analyze dosing patterns in an ethnically diverse cohort to better characterize tolerability and inform future dosing guidelines. In our single-center retrospective study, we evaluated safety and tolerability in TNBC patients undergoing adjuvant capecitabine treatment. The primary endpoint, relative dose intensity (RDI) across eight cycles, was examined alongside subgroup analyses based on age, race, BMI, and initial dose. Secondary endpoints include capecitabine-related side effects and survival. 67 patients who completed adjuvant capecitabine at University of Chicago Medicine (UCM) between January 2017 and November 2022 were eligible. The mean RDI across eight cycles of treatment was 60.2% (95% CI: 0.554-0.650). When compared to the CREATE-X trial, the RDI in our population was significantly lower (0.602 vs. 0.787, p < 0.001). There was no statistically significant difference in average RDI across eight cycles for patients stratified by age, BMI, race, or initial starting dose. The most frequently reported adverse events were hand-foot syndrome (73%), diarrhea (27%), and fatigue (22%), consistent with prior studies. Our data demonstrates that a significant portion of patients have a lower tolerated dose of capecitabine in comparison to the recommended adjuvant dose. Acknowledging the limitations of our single-center analysis, RDI was not significantly affected by age, race, BMI, or initial starting dose.

The SRC-family serves as a therapeutic target in triple negative breast cancer with acquired resistance to chemotherapy.

Resistance to chemotherapy, combined with heterogeneity among resistant tumors, represents a significant challenge in the clinical management of triple negative breast cancer (TNBC). By dissecting molecular pathways associated with treatment resistance, we sought to define patient sub-groups and actionable targets for next-line treatment. Bulk RNA sequencing and reverse phase protein array profiling were performed on isogenic patient-derived xenografts (PDX) representing paclitaxel-sensitive and -resistant tumors. Pathways identified as upregulated in the resistant model were further explored as targets in PDX explants. Their clinical relevance was assessed in two distinct patient cohorts (NeoAva and MET500). Increased activity in signaling pathways involving SRC-family kinases (SFKs)- and MAPK/ERK was found in treatment resistant PDX, with targeted inhibitors being significantly more potent in resistant tumors. Up-regulation of SFKs- and MAPK/ERK-pathways was also detected in a sub-group of chemoresistant patients after neoadjuvant treatment. Furthermore, High SFK expression (of either SRC, FYN and/or YES1) was detected in metastatic lesions of TNBC patients with fast progressing disease (median disease-free interval 27 vs 105 months). Upregulation of SFK-signaling is found in a subset of chemoresistant tumors and is persistent in metastatic lesions. Based on pre-clinical results, these patients may respond favorably to treatment targeting SFKs.

The prognostic impact of Her2 status in early triple negative breast cancer: a Turkish Oncology Group (TOG) study

The studies evaluating the impact of Her2 levels in neoadjuvant setting have conflicting data. The aim of the study was to evaluate the prognostic impact of Her2 status in early triple negative breast cancer(TNBC). In the study TNBC patients who were treated with neoadjuvant chemotherapy (NAC) and surgery were analyzed retrospectively. The primary aim of the study was to analyze the impact of Her2 status(Her2-0 and Her2-low) on pathological complete response (pCR). The secondary objectives were disease free survival (DFS) and overall survival (OS). 620 female triple negative breast cancer patients were evaluated. 427 patients (68.9%) had Her2-0 and 193(31.1%) had her2-low pathology. The pCR rates were similar between Her2-0 and Her2-low patients (33.0% vs. 27.5%, p = 0.098). Although Her2-0 group has better DFS (106 vs. 50 months, p = 0.002), in multivariate analysis it had a HR of 0.74 (p = 0.06). In addition, OS was similar (131 vs. 105 months, p = 0.13) with a HR of 0.88 (p = 0.61). In multivariate analysis; presence of LVI (HR:2.2 (95% CI 1.1–3.5) p = 0.001), Clinical stage T1/T2 (HR:0.39 (95% CI 0.2–0.6) p < 0.001) and lymph node negativity (HR:0.35 (95% CI 0.1–0.9) p = 0.03) were independent factors for OS. Although there were pathological and clinical differences, the pCR, DFS and OS were similar between Her2-0 and Her2-low TNBC patients. The importance of Her2 status of TNBC in neoadjuvant setting should be further studied.

Nuclear localization of APLF facilitates breast cancer metastasis

Most breast cancer deaths result from metastases. We previously reported that DNA repair factor and histone chaperone Aprataxin PNK-like Factor (APLF) is involved in EMT-associated metastasis of triple negative breast cancer (TNBC) cells. However, non-metastatic cells also expressed APLF, the implications of which in disease advancement remain uncertain. Here, we demonstrate that the metastatic prognosis of breast cancer cells may be determined by the cellular localization of APLF. Using TNBC patient samples and cell lines, we discovered that APLF was localized in the nucleus and cytoplasm, whereas other subtypes of breast cancer had cytosolic or perinuclear localization. To investigate metastatic properties in vitro and in vivo, we modeled APLF differential localization by stably producing APLF-tagged nuclear localization signal (NLS) in the luminal subtype MCF7 cells in the absence of putative APLF NLS. Nuclear APLF in non-metastatic MCF7 cells demonstrated pronounced migration, invasion and metastatic potential. We obtained the mechanistic insight from molecular studies that PARP1 could facilitate the transport of APLF from the cytosol to the nucleus, assisting in the metastasis of TNBC cells linked with EMT. Inhibition of PARP1 enzymatic activity with olaparib abrogated the nuclear expression of APLF with loss in expression of genes associated with EMT. Thus, our findings reveal that cellular localization of APLF may predict the risk of breast cancer to metastasize and hence could be exploited to determine the disease progression. We anticipate that the inhibition of cytosolic PARP1-APLF interaction may potentially aid in the prevention of breast cancer metastasis in TNBC patients.