Tumor Progression In Breast Cancer Research Articles

Prognostic Significance of Nuclear Factor kappa B (p65) among Breast Cancer Patients in Cape Coast Teaching Hospital.

Breast cancer is the most prevalent cancer among African women, with high mortality rates in Ghana. Nuclear factor kappa B (NF-kB) has been associated with tumor progression in breast cancer. However, its clinical validation is controversial and understudied with no known published data on NF-kB (p65) among breast cancer patients in Ghana and other African countries. This study assessed the prognostic significance of NF-kB(p65) expression and its association with various clinicopathological features in breast cancer patients. 90 formalin-fixed breast cancer tissues and 15 normal breast tissues were used to determine the expression of NF-kB (p65) using immunohistochemistry. We explored the correlation between expression of NF-kB (p65) and clinicopathological features. NF-kB (p65) was expressed in 86.7% of breast cancer tissues. There was a significant relationship between NF-kB (p65) expression and tumor grade, proliferation index (Ki67), and molecular subtype. High NF-kB (p65) expression in tumor grade 3 was about 10 times that of grade 1 (54.2% versus 5.1%), and Ki67 > 20 was 79.7% compared to 20.3% for Ki67 ≤ 20. Patients with triple-negative breast cancer (TNBC) had 49.1% overexpression of NF-kB (p65) compared to 17%, 25.4% and 8.5% for luminal A, luminal B, and HER 2 cases respectively. This study demonstrates that NF-kB (p65) was highly expressed among breast cancer patients at Cape Coast Teaching Hospital, Ghana especially in TNBC. NF-kB (p65) could serve as a biomarker for cancer stage, progression, prognosis, and as a therapeutic target.

Abstract PO2-24-06: Cancer-Associated Fibroblasts Promote Tumor Stemness in Aggressive Breast Cancers via NDRG1

Abstract Background: Inflammatory breast cancer (IBC) and triple negative breast cancer (TNBC) have the lowest 5-year survival rates among breast cancers: 40% for IBC and 77% for TNBC. Effective treatments for these aggressive tumors are urgently needed. To develop better treatments, it is crucial to understand the underlying mechanisms driving their aggressive biology. Our recent research has identified N-myc downstream regulated gene 1 (NDRG1) as a crucial driver of tumor progression and metastasis in aggressive breast cancers. We have also found that NDRG1 expression in tumors is correlated with poorer outcomes in IBC patients. Additionally, we have observed that cancer-associated fibroblasts (CAFs), derived from breast cancer biopsies, stimulate NDRG1 expression and phosphorylation as well as tumor stemness. Based on these findings, we hypothesize that NDRG1 is a key regulator of tumor stemness and progression, and secreted stromal factors regulate tumor stemness through NDRG1. Methods: To assess tumor stemness, we conducted in vitro experiments by quantifying the CD44+/CD24- subpopulation and performing mammosphere assays in NDRG1 control and depleted cells (SUM149, BCX010, MDA-IBC3). In vivo, we employed a limiting dilution transplantation assay, where NDRG1 control and knockdown SUM149 cells were transplanted into the mammary fat pad at different dilutions. We treated NDRG1 control and knockdown breast cancer cells with different patient-derived CAF-conditioned media (CAFs-CM, 50%, 24h) or control medium. The expression of NDRG1/pNDRG1 and CD44+/CD24- cells was evaluated by immunoblotting and flow cytometry. qPCR array was performed to evaluate tumor stemness markers. Results: NDRG1 depletion significantly reduced the CD44+/CD24- subpopulation (p< 0.001) and the efficiency of mammosphere formation (p=0.001). In vivo limiting dilution experiments demonstrated a substantial reduction in the frequency of breast cancer stem cells in NDRG1 knockdown cells (p= 1 x 10-12). Treatment of IBC cells with CAF-CM derived from breast cancer patients stimulated the cancer stem cell subpopulation [CD44+/CD24-: Control medium (43.1 ± 0.1) vs CAF-CM (55.1 ± 0.7); p=0.004] and increased NDRG1 and phospho-NDRG1 expression. However, the stimulation of NDRG1 knockdown cells with CAF-CM did not significantly alter the cancer stem cell population (0.2 ± 0.2 in Control medium versus 0.4 ± 0.3 in CAF-CM) and the expression of NDRG1/phospho-NDRG1. Additionally, qPCR array analysis revealed the upregulation of several cancer stem cell and self-renewal markers in CAF-CM stimulated cells compared to control-medium treated cells. Conclusions: Our data strongly support the role of NDRG1 as a critical regulator of tumor stemness. Moreover, we have discovered that conditioned media from patient-derived CAFs induces tumor stemness in breast cancer cells, and this effect is dependent on the expression NDRG1. Citation Format: Emilly Villodre, Jenny M Hogstrom, Xiaoding Hu, Nina Kozlova, Debu Tripathy, Taru Muranen, Bisrat Debeb. Cancer-Associated Fibroblasts Promote Tumor Stemness in Aggressive Breast Cancers via NDRG1 [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-24-06.

Pan-inhibition of the three H2S synthesizing enzymes restrains tumor progression and immunosuppression in breast cancer

BackgroundHydrogen sulfide (H2S) is a significant endogenous mediator that has been implicated in the progression of various forms of cancer including breast cancer (BC). Cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3MST) are the three principal mammalian enzymes responsible for H2S production. Overexpression of CBS, CSE and 3MST was found to be associated with poor prognosis of BC patients. Moreover, H2S was linked to an immune-suppressive tumor microenvironment in BC. Recently it was observed that BC cells, in response to single or dual inhibition of H2S synthesizing enzymes, develop an escape mechanism by overexpressing alternative sources of H2S generation. Thus, the aim of this work is to escape the H2S compensatory mechanism by pan repressing the three enzymes using microRNAs (miRNAs) and to investigate their impact on the oncogenic and immunogenic profile of BC cells.MethodsBC female patients (n = 25) were recruited. In-silico analysis was used to identify miRNAs targeting CBS, CSE, and 3MST. MDA-MB-231 cells were cultured and transfected using oligonucleotides. Total RNA was extracted using Biazol, reverse transcribed and quantified using qRT-PCR. H2S levels were measured using AzMc assay. BC hallmarks were assessed using trans-well migration, wound healing, MTT, and colony forming assays.ResultsmiR-193a and miR-548c were validated by eight different bioinformatics software to simultaneously target CBS, CSE and 3MST. MiR-193a and miR-548c were significantly downregulated in BC tissues compared to their non-cancerous counterparts. Ectopic expression of miR-193a and miR-548c in MDA-MB-231 TNBC cells resulted in a marked repression of CBS, CSE, and 3MST transcript and protein levels, a significant decrease in H2S levels, reduction in cellular viability, inhibition of migration and colony forming ability, repression of immune-suppressor proteins GAL3 GAL9, and CD155 and upregulation of the immunostimulatory MICA and MICB proteins.ConclusionThis study sheds the light onto miR-193a and miR-548c as potential pan-repressors of the H2S synthesizing enzymes. and identifies them as novel tumor suppressor and immunomodulatory miRNAs in TNBC.

Pirfenidone ameliorates alcohol-induced promotion of breast cancer in mice.

Alcohol consumption increases the risk of breast cancer and promotes cancer progression. Alcohol exposure could affect both processes of the mammary carcinogenesis, namely, the cell transformation and onset of tumorigenesis as well as cancer aggressiveness including metastasis and drug resistance/recurrence. However, the cellular and molecular mechanisms underlying alcohol tumor promotion remain unclear. There are four members of the mammalian p38 mitogen-activated protein kinase (MAPK) family, namely, p38α, p38β, p38γ and p38δ. We have previously demonstrated alcohol exposure selectively activated p38γ MAPK in breast cancer cells in vitro and in vivo. Pirfenidone (PFD), an antifibrotic compound approved for the treatment of idiopathic pulmonary fibrosis, is also a pharmacological inhibitor of p38γ MAPK. This study aimed to determine whether PFD is useful to inhibit alcohol-induced promotion of breast cancer. Female adolescent (5 weeks) MMTV-Wnt1 mice were exposed to alcohol with a liquid diet containing 6.7% ethanol. Some mice received intraperitoneal (IP) injection of PFD (100 mg/kg) every other day. After that, the effects of alcohol and PFD on mammary tumorigenesis and metastasis were examined. Alcohol promoted the progression of mammary tumors in adolescent MMTV-Wnt1 mice. Treatment of PFD blocked tumor growth and alcohol-promoted metastasis. It also significantly inhibited alcohol-induced tumorsphere formation and cancer stem cell (CSC) population. PFD inhibited mammary tumor growth and alcohol-promoted metastasis. Since PFD is an FDA-approved drug, the current findings may be helpful to re-purpose its application in treating aggressive breast cancer and alcohol-promoted mammary tumor progression.

Abstract B044: Intracellular sclerostin plays a vital role in tumor progression and metastasis in triple-negative breast cancer

Abstract Background: Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with limited treatment options. It is essential to continue advancing well-defined molecular targets in TNBC. Sclerostin (SOST) is mostly concerned as an osteocyte secreted protein and a drug target for osteoporosis. Recently, sclerostin was reported to be expressed in a majority of clinical TNBC tissues. Upregulated SOST expression was reported to be associated with worse prognosis in breast cancer patients. This study aimed to investigate the role of sclerostin in TNBC. Methods: Cell proliferative ability was evaluated by colony formation assay. Cell migratory and invasive abilities were evaluated by transwell assay. The tumor growth and metastasis were evaluated in 4T1 orthotopic and metastatic mouse models. The cellular uptake of antibody and aptamer was evaluated by fluorescence microscopy. Results: It was found that sclerostin knockout demonstrated inhibitory effects on proliferation and migration/invasion in both human (MDA-MB-231) and murine (4T1) TNBC cell lines in vitro. Surprisingly, no tumor growth and metastasis were found in 4T1-sost KO inoculated orthotopic and metastatic mouse models compared to their wildtype counterparts. It suggested the vital role of sclerostin in TNBC. Anti-sclerostin antibody (Scl-Ab) could not be internalized by TNBC cells and demonstrated no effects on proliferation and migration/invasion in vitro. On the other hand, no difference in proliferation and migration/invasion was also observed between TNBC cells with and without supplementing sclerostin in vitro. Genetically, there was no difference in tumor growth between 4T1 inoculated WT mice and SOST -/− mice. Pharmacologically, no difference was also observed in tumor growth between Scl-Ab treatment and IgG control in 4T1 inoculated mice. It suggested that the role of extracellular and systemic sclerostin could be excluded in TNBC. Aptamers are single-strand nucleic acids which bind to specific targets. It was found that sclerostin-specific aptamer (Scl-Ap) could be internalized by TNBC cells and demonstrated inhibitory effects on proliferation and migration in vitro. Consistently, Scl-Ap demonstrated inhibitory effects on tumor growth in 4T1 inoculated mice. It suggested that intracellular sclerostin might play a vital role in TNBC. Conclusions: Intracellular sclerostin plays a vital role in TNBC progression and metastasis. Citation Format: Meiheng SUN, Shuangying Qiao, Hang Luo, Xin Yang, Liu Yang, Huarui Zhang, Zefeng Chen, Luyao Wang, Xiaohui Tao, Yuanyuan Yu, Yuan Ma, Fenglai Yuan, Daqing Ma, Qianjun Chen, Aiping Lu, Bao-ting Zhang, Ge Zhang, Fangfei Li. Intracellular sclerostin plays a vital role in tumor progression and metastasis in triple-negative breast cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B044.

Troponin T1 silencing inhibits paclitaxel resistance and the development of breast cancer via suppressing rat sarcoma virus/rapidly accelerated fibrosarcoma 1 pathway.

We aimed to determine the role of Troponin T1 (TNNT1) in paclitaxel (PTX) resistance and tumor progression in breast cancer (BC). Differentially expressed genes were obtained from the GSE4298 and GSE90564 datasets. Hub genes were isolated from protein-protein interaction networks and further validated by real-time quantitative polymerase chain reaction. The effect of TNNT1 on PTX resistance was determined using cell counting kit-8, 5-ethynyl-2'-deoxyuridine, wound healing, transwell, flow cytometry assays, and subcutaneous xenografted tumor model. Western blotting was used to detect proteins associated with PTX resistance, apoptosis, migration, invasion, and other key pathways. Hematoxylin-eosin and immunohistochemical staining were used to evaluate the role of TNNT1 in tumors. After comprehensive bioinformatic analysis, we identified CCND1, IGF1, SFN, INHBA, TNNT1, and TNFSF11 as hub genes for PTX resistance in BC. TNNT1 plays a key role in BC and is upregulated in PTX-resistant BC cells. TNNT1 silencing inhibited PTX resistance, proliferation, migration, and invasion while promoting apoptosis of PTX-resistant BC cells. Tumor xenograft experiments revealed that TNNT1 silencing suppresses PTX resistance and tumor development in vivo. In addition, TNNT1 silencing inhibited the expression of proteins in the rat sarcoma virus (RAS)/rapidly accelerated fibrosarcoma1 (RAF1) pathway in vivo. Treatment with a RAS/RAF1 pathway activator reversed the inhibitory effect of TNNT1 silencing on proliferation, migration, and invasion while promoting apoptosis of PTX resistance BC cells. Silencing of TNNT1 suppresses PTX resistance and BC progression by inhibiting the RAS/RAF1 pathway, which is a promising biomarker and therapeutic target for drug resistance in BC.

Blood mononuclear cell molecular landscape associated with tumor progression in triple-negative breast cancer

Introduction. triple negative breast cancer is an aggressive clinical phenotype characterized by poor prognosis. immune system plays an important role in the development, treatment response, and progression of solid tumor. The search for immune-related markers associated with the prediction of treatment efficacy and disease prognosis, and based on the use of high-resolution molecular techniques, is a promising area of research, the results of which can be translated into clinical practice. Case description. The molecular profile of blood mononuclear cells in a 48-year-old female patient with histologically proven triple negative breast cancer (estrogen Receptor – 0; progesteron Receptor – 0; Her2/neu – 0; gata-3 – 0, androgen Receptor – 0 and Ki67 – 70 %) was described. The patient did not response to neoadjuvant chemotherapy with 4 cycles of paclitaxel + carboplatin followed by 2 cycles of adriamycin + cyclophosphamide. The patient underwent surgery. disease progression (pelvic bone metastases) occurred 2 months after surgery. The features of blood lymphocytes and monocytes associated with a lack of response to neoadjuvant chemotherapy and disease progression were described.Conclusion. This clinical case demonstrates that sequencing of peripheral blood mononuclear cells can be used as a method for identifying predictive markers of therapy efficacy and developing personalized treatments for patients with triple negative breast cancer.

Vitamin B5 supports MYC oncogenic metabolism and tumor progression in breast cancer

Tumors are intrinsically heterogeneous and it is well established that this directs their evolution, hinders their classification and frustrates therapy1–3. Consequently, spatially resolved omics-level analyses are gaining traction4–9. Despite considerable therapeutic interest, tumor metabolism has been lagging behind this development and there is a paucity of data regarding its spatial organization. To address this shortcoming, we set out to study the local metabolic effects of the oncogene c-MYC, a pleiotropic transcription factor that accumulates with tumor progression and influences metabolism10,11. Through correlative mass spectrometry imaging, we show that pantothenic acid (vitamin B5) associates with MYC-high areas within both human and murine mammary tumors, where its conversion to coenzyme A fuels Krebs cycle activity. Mechanistically, we show that this is accomplished by MYC-mediated upregulation of its multivitamin transporter SLC5A6. Notably, we show that SLC5A6 over-expression alone can induce increased cell growth and a shift toward biosynthesis, whereas conversely, dietary restriction of pantothenic acid leads to a reversal of many MYC-mediated metabolic changes and results in hampered tumor growth. Our work thus establishes the availability of vitamins and cofactors as a potential bottleneck in tumor progression, which can be exploited therapeutically. Overall, we show that a spatial understanding of local metabolism facilitates the identification of clinically relevant, tractable metabolic targets.

Association of the m6 A reader IGF2BP3 with tumor progression and brain-specific metastasis in breast cancer.

This study aimed to determine the role of insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3), an N6 -methyladinosine reader, in the progression and distant metastasis of breast cancer. IGF2BP3 expression was assessed in 152 pairs of breast cancer and adjacent normal tissue (ANT) by real-time quantitative polymerase chain reaction and in 561 cases of breast cancer and 163 cases of ANT by immunohistochemistry. Survival curves were estimated using the Kaplan-Meier method and then compared statistically using the log-rank test. The prognostic role of IGF2BP3 was determined by Cox regression analysis. Analysis of public gene data sets revealed that IGF2PB3 predicted distant metastasis in breast cancer and was highly correlated with brain metastasis. In the clinical retrospective cohort, the positive rate of IGF2BP3 increased gradually with breast cancer progression. Positive IGF2BP3 expression was related to poor distant metastasis-free survival (DMFS, p=.030) and Cox regression analysis identified IGF2BP3 as an independent risk factor for DMFS (hazard ratio, 1.876; 95% confidence interval, 1.128-3.159; p=.019). Positive IGF2BP3 expression was markedly related to breast cancer brain metastasis (p=.011) but not to lung and bone metastasis. Moreover, patients with IGF2BP3-positive brain metastasis had lower survival than patients with IGF2BP3-negative brain metastasis (p=.041). Gene expression profiling results indicated that high IGF2BP3 expression was associatedwith the PD-1 checkpoint pathway, HER2-HER3 signaling, and epithelial-mesenchymal transition. IGF2BP3 may serve as a novel predictive biomarker and a potential therapeutic target for breast cancer brain metastasis, which warrants further investigation. As an m6 A reader, IGF2BP3 is dysregulated and implicated in various cancers but its role in breast cancer has not been fully clarified. In this study, we found that IGF2BP3 was upregulated in breast cancer and IGF2BP3 expression increased gradually during breast cancer progression. IGF2BP3 expression exerted no effect on the overall survival and breast cancer-specific survival of breast cancer patients; however, IGF2BP3-positive patients were more likely to develop distant metastasis than IGF2BP3-negative patients. In addition, IGF2BP3 was associated with brain-specific metastasis in breast cancer patients. These findings warrant further investigation because they provide a rationale for novel predictive or therapeutic approaches.

The Cell-Autonomous Pro-Metastatic Activities of PD-L1 in Breast Cancer Are Regulated by N-Linked Glycosylation-Dependent Activation of STAT3 and STAT1.

PD-L1 has been characterized as an inhibitory immune checkpoint, leading to the suppression of potential anti-tumor immune activities in many cancer types. In view of the relatively limited efficacy of immune checkpoint blockades against PD-L1 in breast cancer, our recent study addressed the possibility that in addition to its immune-inhibitory functions, PD-L1 promotes the pro-metastatic potential of the cancer cells themselves. Indeed, our published findings demonstrated that PD-L1 promoted pro-metastatic functions of breast cancer cells in a cell-autonomous manner, both in vitro and in vivo. These functions fully depended on the integrity of the S283 intracellular residue of PD-L1. Here, using siRNAs and the S283A-PD-L1 variant, we demonstrate that the cell-autonomous pro-metastatic functions of PD-L1-tumor cell proliferation and invasion, and release of the pro-metastatic chemokine CXCL8-required the activation of STAT3 and STAT1 in luminal A and triple-negative breast cancer cells. The cell-autonomous pro-metastatic functions of PD-L1 were potently impaired upon inhibition of N-linked glycosylation (kifunensine). Site-specific mutants at each of the N-linked glycosylation sites of PD-L1 (N35, N192, N200, and N219) revealed that they were all required for PD-L1-induced pro-metastatic functions to occur; the N219 site was the main regulator of STAT3 and STAT1 activation, with accompanying roles for N192 and N200 (depending on the cell type). Using a T cell-independent mouse system, we found that cells expressing N35A-PD-L1 and N219A-PD-L1 had a significantly lower tumorigenic and metastatic potential than cells expressing WT-PD-L1. TCGA analyses revealed significant associations between reduced survival and high levels of α-mannosidase II (inferring on N-linked glycosylation) in breast cancer patients. These findings suggest that N-linked glycosylation of PD-L1 may be used to screen for patients who are at greater risk of disease progression, and that modalities targeting N-linked glycosylated PD-L1 may lead to the inhibition of its cell-autonomous pro-metastatic functions and to lower tumor progression in breast cancer.

Inhibition of Notch Signaling Enhances Antitumor Activity of Histone Deacetylase Inhibitor LAQ824.

As a novel histone deacetylase inhibitor (HDACi), LAQ824 (LAQ) effectively inhibits the proliferation of hematological malignancies and solid tumors. However, phase II trials of LAQ in solid tumors were terminated due to dose-dependent toxicity. Furthermore, LAQ has been shown to induce the activation of the Notch signaling pathway in hematopoietic stem cells, which is associated with tumor progression and drug resistance in colon and breast cancers. Therefore, in this study, we investigated the strategy of LAQ combined with a Notch signaling pathway inhibitor to treat solid tumors. We used RT-PCR and Western blot methods to demonstrate that LAQ upregulated the Notch signaling pathway in solid tumor cell lines at the molecular level. The combination of LAQ and a Notch signaling pathway inhibitor was shown by a Chou-Talalay assay to have a synergistic effect in inhibiting solid tumor cell line proliferation in vitro. We also demonstrated that the combination of LAQ and a Notch signaling pathway inhibitor significantly inhibited the growth of tumor cells in vivo using an allograft tumor model. This study indicates that inhibition of the Notch signaling pathway provides a valuable strategy for enhancing solid tumor sensitivity to LAQ.

SP1-Induced Upregulation of LncRNA AFAP1-AS1 Promotes Tumor Progression in Triple-Negative Breast Cancer by Regulating mTOR Pathway.

The long non-coding RNA (lncRNA) actin fiber-associated protein-1 antisense RNA 1 (AFAP1-AS1) exerted oncogenic activity in triple-negative breast cancer (TNBC). We designed this study and conducted it to investigate the upstream regulation mechanism of AFAP1-AS1 in TNBC tumorigenesis. In this work, we proved the localization of AFAP1-AS1 in the cytoplasm. We elucidated the mechanism by which the transcription factor specificity protein 1 (SP1) modulated AFAP1-AS1 in TNBC progression, which has yet to be thoroughly studied. Dual luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay revealed a strong affinity of SP1 toward the promoter regions P3 of AFAP1-AS1, proving the gene expression regulation of AFAP1-AS1 via SP1 in TNBC. Additionally, SP1 could facilitate the tumorigenesis of TNBC cells in vitro and in vivo by regulating the AFAP1-AS1 expression. Furthermore, silenced AFAP1-AS1 suppressed the expression of genes in the mTOR pathway, such as eukaryotic translation initiation factor 4B (EIF4B), mitogen-activated protein kinase-associated protein 1 (MAPKAP1), SEH1-like nucleoporin (SEH1L), serum/glucocorticoid regulated kinase 1 (SGK1), and its target NEDD4-like E3 ubiquitin protein ligase (NEDD4L), and promoted the gene expression of s-phase kinase-associated protein 2 (SKP2). Overall, this study emphasized the oncogenic role of SP1 and AFAP1-AS1 in TNBC and illustrated the AFAP1-AS1 upstream interaction with SP1 and the downstream modulatory of mTOR signaling, thus offering insights into the tumorigenesis mechanism in TNBC.

ILT4 reprograms glucose metabolism to promote tumor progression in triple negative breast cancer.

Triple negative breast cancer (TNBC) is the most aggressive and poorly-treated subtype of breast cancer. Identifying novel drivers and mechanisms for tumor progression is quite essential for precise targeted therapy of TNBC. Immunoglobulin-like transcript (ILT) 4 is a classic myeloid suppressor for their activation and immune response. Our recent results found that ILT4 is also high expressed in lung cancer cells where has a role in promoting immune evasion and thus tumor formation. However, the expression and function of ILT4 in breast cancer remains elusive. Here, using our patient cohort and public database analysis, we found that TNBC displayed the most abundant ILT4 expression among all breast cancer subtypes. Functionally, enriched ILT4 promoted TNBC cell proliferation, migration and invasion in vitro, as well as tumor growth and metastasis in vivo. Further mechanistic analysis revealed that ILT4 reprogrammed aerobic glycolysis of tumor cells via AKT/mTOR signaling-mediated glucose transporter 3 (GLUT3) and Pyruvate kinase muscle 2 (PKM2) overexpression. ILT4 inhibition in TNBC reduced tumor progression and GLUT3/PKM2 expression in vivo. Our study identified a novel driver for TNBC progression and proposed a promising strategy to combat TNBC by targeting ILT4.

Delivery of miR-200c-3p Using Tumor-Targeted Mesoporous Silica Nanoparticles for Breast Cancer Therapy.

Despite advances in breast cancer treatment, it remains the leading cause of cancer-related death in women worldwide. In this context, microRNAs have emerged as potential therapeutic targets but still present some limitations for in vivo applications. Particularly, miR-200c-3p is a well-known tumor suppressor microRNA that inhibits tumor progression and metastasis in breast cancer through downregulating ZEB1 and ZEB2. Based on the above, we describe the design and validation of a nanodevice using mesoporous silica nanoparticles for miR-200c-3p delivery for breast cancer treatment. We demonstrate the biocompatibility of the synthesized nanodevices as well as their ability to escape from endosomes/lysosomes and inhibit tumorigenesis, invasion, migration, and proliferation of tumor cells in vitro. Moreover, tumor targeting and effective delivery of miR-200c-3p from the nanoparticles in vivo are confirmed in an orthotopic breast cancer mouse model, and the therapeutic efficacy is also evidenced by a decrease in tumor size and lung metastasis, while showing no signs of toxicity. Overall, our results provide evidence that miR-200c-3p-loaded nanoparticles are a potential strategy for breast cancer therapy and a safe and effective system for tumor-targeted delivery of microRNAs.

In Silico Exploration of Dietary Polyphenol, Bisdemethoxycurcumin as a Potential CXCL12 Inhibitor in Breast Cancer Treatment

Breast cancer stands as one of the most prevalent malignancies in women worldwide. The World Health Organization reported 2.3 million new cases and 685,000 fatalities due to breast cancer in 2020. In India alone, 162,468 new diagnoses and 87,090 deaths were recorded in 2018. CXCL12, also known as stromal cell-derived factor 1 (SDF-1), plays a significant role in tumor progression and metastasis in breast cancer, rendering it a promising target for intervention. Curcumin and its derivatives are known to inhibit breast cancer and enhance the efficacy of chemotherapeutic drugs. This study explores the potential of Bisdemethoxycurcumin, a synthesized derivative of curcumin, as a CXCL12 inhibitor in breast cancer. Our in-silico screening of Bisdemethoxycurcumin demonstrated a strong binding affinity to CXCL12, surpassing that of the reference compound, Plerixafor. We also compared our lead molecule with the reference compound (Plerixafor). Conversely, we observe that Bisdemethoxycurcumin shows a good binding affinity with the target protein and shows a strong bond interaction, particularly H-bond interaction in molecular docking and MD simulation studies both. Our findings identify Bisdemethoxycurcumin as a lead compound for future studies, necessitating validation through in vitro and in vivo investigations.

The RNA binding protein MEX3A promotes tumor progression of breast cancer by post-transcriptional regulation of IGFBP4

PurposeBreast cancer (BC) is the most frequent malignant tumor in women worldwide with exceptionally high morbidity. The RNA-binding protein MEX3A plays a crucial role in genesis and progression of multiple cancers. We attempted to explore its clinicopathological and functional significance in BC in which MEX3A is expressed.MethodsThe expression of MEX3A detected by RT-qPCR and correlated the results with clinicopathological variables in 53 BC patients. MEX3A and IGFBP4 profile data of BC patients were downloaded from TCGA and GEO database. Kaplan-Meier (KM) analysis was used to estimate the survival rate of BC patients. Western Blot, CCK-8, EdU, colony formation and flow cytometry were performed to investigate the role of MEX3A and IGFBP4 in BC cell proliferation, invasion and cell cycle in vitro. A subcutaneous tumor mouse model was constructed to analyze in vivo growth of BC cells after MEX3A knockdown. The interactions among MEX3A and IGFBP4 were measured by RNA pull-down and RNA immunoprecipitation.ResultsThe expression of MEX3A was upregulated in BC tissues compared to adjacent tissues and high expression of MEX3A was associated with poor prognosis. Subsequent in vitro studies demonstrated that MEX3A knockdown inhibited BC cells proliferation and migration, as well as xenograft tumor growth in vivo. The expression of IGFBP4 was significantly negatively correlated with MEX3A in BC tissues. Mechanistic investigation showed that MEX3A binds to IGFBP4 mRNA in BC cells, decreasing IGFBP4 mRNA levels, which further activated the PI3K/AKT and other downstream signaling pathways implicated cell cycle progression and cell migration.ConclusionOur results indicate that MEX3A plays a prominent oncogenic role in BC tumorigenesis and progression by targeting IGFBP4 mRNA and activating PI3K/AKT signaling, which can be used as a novel therapeutic target for BC.

ARHGAP25 suppresses the development of breast cancer by an ARHGAP25/Wnt/ASCL2 feedback loop.

Downregulation of ARHGAP25 was found in the tumor samples from breast cancer patients and five breast cancer cell lines. However, its precise role and molecular mechanisms in breast cancer remain completely unknown. Herein, we found that knockdown of ARHGAP25 in breast cancer cells promoted proliferation, migration and invasion of breast cancer cells. Mechanistically, ARHGAP25 silence facilitated the activation of the Wnt/β-catenin pathway and the upregulation of its downstream molecules (including c-Myc, Cyclin D1, PCNA, MMP2, MMP9, Snail, and ASCL2) by directly regulating Rac1/PAK1 in breast cancer cells. In vivo xenograft experiments indicated ARHGAP25 silence promoted tumor growth and activated the Wnt/β-catenin pathway. In contrast, overexpression of ARHGAP25 in vitro and in vivo impeded all of the above cancer properties. Intriguingly, ASCL2, a downstream target of the Wnt/β-catenin pathway, transcriptionally repressed the expression of ARHGAP25 and therefore constituted a negative feedback loop. Moreover, bioinformatics analysis indicated that ARHGAP25 is significantly correlated with tumor immune cell infiltration and the survival of patients with different immune cell subgroups in breast cancer. Collectively, our work revealed that ARHGAP25 suppressed tumor progression of breast cancer. It provides a novel insight for the treatment of breast cancer.

Tumor-expressed factor VII is associated with survival and regulates tumor progression in breast cancer.

Cancer enhances the risk of venous thromboembolism, but a hypercoagulant microenvironment also promotes cancer progression. Although anticoagulants have been suggested as a potential anticancer treatment, clinical studies on the effect of such modalities on cancer progression have not yet been successful for unknown reasons. In normal physiology, complex formation between the subendothelial-expressed tissue factor (TF) and the blood-borne liver-derived factor VII (FVII) results in induction of the extrinsic coagulation cascade and intracellular signaling via protease-activated receptors (PARs). In cancer, TF is overexpressed and linked to poor prognosis. Here, we report that increased levels of FVII are also observed in breast cancer specimens and are associated with tumor progression and metastasis to the liver. In breast cancer cell lines, tumor-expressed FVII drives changes reminiscent of epithelial-to-mesenchymal transition (EMT), tumor cell invasion, and expression of the prometastatic genes, SNAI2 and SOX9. Invivo, tumor-expressed FVII enhanced tumor growth and liver metastasis. Surprisingly, liver-derived FVII appeared to inhibit metastasis. Finally, tumor-expressed FVII-induced prometastatic gene expression independent of TF but required a functional endothelial protein C receptor, whereas recombinant activated FVII acting via the canonical TF:PAR2 pathway inhibited prometastatic gene expression. Here, we propose that tumor-expressed FVII and liver-derived FVII have opposing effects on EMT and metastasis.

Robust eIF4B levels undermine invasive growth and immune evasion mechanisms in murine triple negative breast cancer models.

Abstract Dysregulated protein synthesis is seen in many aggressive cancers, including metastatic breast cancer. However, the specific contributions of certain translation initiation factors to in vivo disease remain undefined. This is particularly true of eIF4B, an RNA-binding protein and cofactor of the RNA helicase eIF4A and associated eIF4F cap-binding complex. While eIF4A, eIF4G, and eIF4E are known to contribute to the progression of many cancer types, the role played by eIF4B in breast cancer remains relatively unclear. We therefore explored how naturally divergent and experimentally modulated eIF4B levels impact tumor growth and progression in murine triple negative breast cancer (TNBC) models. Surprisingly, we found that higher eIF4B levels in mouse and human breast cancers were associated with less aggressive phenotypes. shRNA-mediated eIF4B knockdown in TNBC lines failed to markedly alter proliferation and global translation in cells grown in vitro and only modestly hindered primary mammary tumor growth in mice. However, eIF4B knockdown significantly enhanced invasive growth in vitro and exacerbated both tumor burden and mortality relative to nontargeting shRNA controls in a model of metastatic disease. Deposited patient data reinforced a link between high eIF4B levels and better outcomes. Interestingly, in vitro and in vivo studies associated low eIF4B expression with more formidable immune evasion. These findings suggest that eIF4B levels impact metastatic disease in part through immunomodulatory mechanisms beyond the factor’s traditional role supporting eIF4/F directed translation. Future studies should explore the impact of these findings for personalizing treatment decisions and developing future therapies.

Morphological features of epithelial-mesenchymal transformation and its effect on tumor progression of breast cancer

Introduction. Breast cancer is in the first place in the structure of morbidity among all malignant neoplasms in women. The prognosis of the disease depends on the tumor degree, including the presence of epithelial-mesenchymal transformation (EMT), the degree of invasion, the proliferative index, the preservation or absence of estrogen, progesterone, and epidermal growth factor receptors.Aim: To study the immunohistochemical and morphological characteristics of the epithelial-mesenchymal transformation of breast cancer.Material and Methods. Immunohistochemical study with antibodies to AE1/AE3, HMW, CK18, Snail, HER2/neu, E-cadherin, Vimentin, α-SMA, CD34, Ki-67 and p63 was performed in 60 patients of different age with breast cancer. Native preparations were stained with picrofuchsin according to van Gieson Alcian blue. Inflammatory infiltrate cells were examined for antibodies CD45, CD3, CD4, CD8, CD20, CD68.Results. In ductal carcinoma, positive expression for estrogen and progesterone was found in 82.7% and 86.3%, respectively, the proliferation index ranged before 66,6%, and p-53 was positive in 97%. In lobular cancer, positive expression to estrogen and progesterone was observed in 83.4% and 66.6%, respectively, the index of proliferative activity at the level of 50%, and p-53 was positive in 66.6%. Positive moderate expression of HER-2/neu was determined in 47% of ductal and 50% of lobular cancers. Estrogen plays an important role in the development of invasive breast cancer, leads to tumor progression and contributes to EMT. EMT, in turn, leads to the expression of E-cadherin associated with a worse survival prognosis. EMT indirectly leads to the intensification of angiogenesis, and the presence of a large number of newly formed vessels increases the risk of metastasis. Histochemical methods were used to determine the growth of fibrous tissue around invasively growing cancer complexes. Cells located perifocally looked like fibrobla ts, immunohistochemically moderately expressed Vimentin and weakly expressed pancytokeratin, which proved the tumor nature of the cells and the acquisition of mesenchymal features by them. The inflammatory infiltrate along the periphery of the tumor growth consisted mainly of T- and B-lymphocytes, and around the cancer complexes - of B-lymphocytes and macrophages.Conclusion. The study of the immunohistochemical tumor phenotype will make it possible to prescribe adequate polychemotherapy and determine the prognosis of the course of the disease.