Metastasis Of Breast Cancer Cells Research Articles

Poncirin Impact on Human HER2 Breast Cancer Cells: Inhibiting Proliferation, Metastasis, and Tumor Growth in Mice Potentially through The PI3K/AKT Pathway.

Breast cancer is a prevalent and heterogeneous disease, with human epidermal growth factor receptor-2 (HER2) overexpression occurring in over 20% of cases. Poncirin, a biologically active flavonone derived from the immature dried fruits of Poncirus trifoliata, is a 7-O-neohesperidoside of isosakuranetin with a well-documented history in traditional Chinese medicine for its health-promoting properties. While the previous research hinted at its potential as an anticancer agent, its specific effects on HER2 overexpressing breast cancer cells remain largely unexplored. The aim of this study is to investigate the specific effects of Poncirin, on HER2 overexpressing breast cancer cells. In experimental study, we assessed cell proliferation using the CCK-8 assay and explored cell migration and invasion with transwell assays. Additionally, we evaluated colony formation ability and examined apoptosis through the acridine orange/ethidium bromide (AO/EB) and Annexin V-fluorescein isothiocyanate (FITC)/ propidium iodide (PI) staining methods. The study also delved into the molecular mechanisms involved by scrutinizing the phosphatidylinositol 3-kinase/serine-threonine protein kinase (PI3K/AKT) signaling pathway via Western blotting. Furthermore, the researchers conducted in vivo experiments using mouse models to corroborate the findings in a living organism. Poncirin demonstrated a remarkable ability to selectively inhibit proliferation and metastasis of HER2 overexpressing breast cancer cells. Mechanistically, the compound seemed to exert its effects by modulating the PI3K/AKT signaling pathway, implying its central role in the observed anticancer effects. These findings were further substantiated by in vivo experiments, which consistently showed a reduction in tumor growth when poncirin was administered. This study underscores potential of poncirin as a potent agent for restraining the growth and metastasis of HER2 overexpressing breast cancer cells. The evidence suggests that poncirin efficacy may be attributed to its modulation possibly through PI3K/AKT pathway.

Sirtinol, a SIRT1 inhibitor, inhibits the EMT and metastasis of 4T1 breast cancer cells and impacts the tumor microenvironment.

The impact of epigenetic drugs on metastasis and the immunological microenvironment is poorly understood. In this study, we looked at how sirtinol, a SIRT1 inhibitor, affected epithelial-mesenchymal transition (EMT), metastasis, and the immune cells. In vitro experiments were carried out using tumor conditioned medium (TCM). For in vivo experiments, sirtinol was administered i.p. in tumor bearing BALB/c mice at a dose of 2 mg/kg body weight either alone or in combination with cisplatin. Estimation of cytokines was carried out using ELISA or ELIspot. Estimation of different markers was done using flow cytometry or western blot. Sirtinol, a SIRT1 inhibitor, was found to be cytotoxic to 4T1 breast cancer cells with no synergistic effects with cisplatin, both under in vitro and in vivo conditions (p < 0.05). Sirtinol significantly reduced cancer cell metastasis to the spleen which was supported by in vitro findings such as decreased vimentin expression and cell mobility in migration and wound healing assays (p < 0.01). Studies on the effects of 4T1 tumor-conditioned medium on spleen cells indicated changes in T cell proliferation as well as differentiation (p < 0.01). In tumor bearing mice, spleen cells showed elevated IFN-γ secretion, increased CD11b+ cells, and decreased T cells (p < 0.01). This was reversed by sirtinol as well as the combination treatment, which may also have contributed to metastasis inhibition (p < 0.01). Sirtinol, a SIRT1 inhibitor inhibits EMT and metastasis of 4T1 breast cancer cells and also has an impact on the immune microenvironment.

7881 Using Selective Estrogen Receptor Modulators to Reveal Therapeutic Vulnerabilities in ESR1 Mutant Breast Cancer

Abstract Disclosure: S.W. Fanning: Grant Recipient; Self; Olema Oncology. Hotspot activating somatic mutations to ESR1, the gene for estrogen receptor alpha (ER), enable hormone therapy resistance and drive breast cancer metastasis. The Y537S missense mutation within the ER ligand binding domain is the most activating, therapy resistant, and increases metastatic potential. Next generation antiestrogens including lasofoxifene (laso) and elacestrant (RAD1901) show improved progression-free survival over fulvestrant (fulv), but further progress is needed to achieve durable response. To fully address Y537S ESR1, it is critically important to understand how the mutation boosts metastasis. We have developed a small molecule antiestrogen, T6I-29, that uniquely impacts transcriptional pathways related to cell-cell adhesions and morphology. Two allele-specific phenotypes identified by the Oesterreich Laboratory enhance the metastasis of Y537S ESR1 breast cancer cells. T6I-29-specific pathway effects were driven by a significant downregulation of dickkopf-1 (DKK1), which was also observed but to a lesser extent with fulv, laso, and RAD1901. DKK1 is an immunosuppressive, tumor-secreted glycoprotein and its overexpression correlates with poor outcomes in multiple cancers. However, DKK1 acts as a tumor-suppressor in colorectal cancer, which does not rely on ER. Our preliminary studies suggest that DKK1 plays a role in ER+ breast cancer progression. We measured significantly elevated DKK1 protein levels in the blood plasma of 108 diverse ER+ breast cancer patients compared to 100 matched healthy female donors and levels increase coincident with tumor stage. Unfortunately, we lack ESR1 mutation status and other critical details to make further insights on these patients. DKK1 gene expression and protein secretion is stimulated in WT cells by the pathogenic hormone 17β-estradiol (E2), while it is constitutively expressed in Y537S ESR1 cells. DKK1 is characterized as a WNT antagonist but can also induce PI3K/Akt signaling. Interestingly, DKK1 is elevated and ERα responsive in WT not mutant PI3KCA cell lines. DKK1 knockdown also reduced proliferation of Y537S ESR1 breast cancer cells where elevated DKK1 was observed. Presentation: 6/3/2024

Isoliquiritigenin: A natural compound with a promising role in inhibiting breast cancer lung metastasis

Background and aimIsoliquiritigenin (ISL) is a dietary bioactive compound that is derived from the roots of licorice and various other plants. Accumulating evidence suggests that ISL has noteworthy anticancer activity in a variety of cancer cells, but it is currently unknown how ISL affects the invasion and migration of breast cancer (BC) cells. Hence, the purpose of this study to determine the inhibitory effect of ISL on cell invasion, migration, and metastasis of BC cells in 4T1-treated lung metastatic animal models. Experimental ProcedureISL was found to inhibit BC lung metastasis, as confirmed by MTT assay, clonogenic assay, wound healing assay, transwell assay, histological analysis, western blot and bioluminescence assay in the xenograft model. Results and conclusionThe in vitro studies revealed that ISL treatment significantly prevented BC cell invasion and migration for 24 h. ISL decreased the protein expressions of PI3K, Akt, p-Akt, mTOR, p-mTOR, matrix metalloproteinase (MMP)-2, MMP-9, and N-cadherin , thereby inhibiting BC cell invasion. In addition, ISL decreased MMP-2/9 and N-cadherin expression in lung tissues and reduced mouse 4T1 BC cell lung metastasis. Based on these findings, it suggests that ISL inhibits cell migration and invasion in BC cells by inhibiting the PI3K/Akt signaling pathway and decreasing the activation of MMP-2 and MMP-9 expression. Therefore, ISL may be useful in managing BC invasion and metastasis.

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.

NUAKs promote mTOR/c-Myc-induced glucose and glutamine reprogramming for cell growth and metastasis in breast cancer cells

Breast cancer progression and metastasis are closely connected to changes in glucose and glutamine metabolism. While Novel (nua) kinase family 1 (NUAK1) and Novel (nua) kinase family 2 (NUAK2), which are two members of the AMPK-related kinases, have been associated with breast tumorigenesis, their role in the metabolic reprogramming that occurs during breast cancer progression remains unclear. Our research uncovers that NUAKs expression is significantly higher in breast cancer tissues and cell lines, and it is positively related to glycolysis, the pentose phosphate pathway (PPP), glutamine metabolism, and a poor prognosis for breast cancer patients. We show that NUAKs significantly increase metabolic reprogramming, including aerobic glycolysis, PPP, and glutamine metabolism in triple negative breast cancer subtypes but only induce aerobic glycolysis and PPP in luminal breast cancer subtypes to meet the anabolic demands of rapidly dividing breast cancer cells. In contrast, the depletion of NUAKs has the opposite effect. Mechanistic insights reveal that NUAKs activate mammalian target of rapamycin (mTOR) signaling, which in turn upregulates the c-Myc transcription factor, a crucial regulator of glucose and glutamine metabolic gene expression. Moreover, we demonstrate that NUAKs enhance mTOR/c-Myc signaling pathways, leading to increased glucose and glutamine reprogramming, which supports rapid cell proliferation and metastatic potential in breast cancer cells. Importantly, pretreating breast cancer cells with mTOR inhibitors blocked the metabolic reprogramming and tumor-promoting effect of NUAK1/2. Therefore, targeting NUAKs may represent a novel therapeutic strategy for the treatment of breast cancer.

Retraction: Ultrasonic irradiation and SonoVue microbubbles-mediated RNA interfering targeting PRR11 inhibits breast cancer cells proliferation and metastasis but promotes apoptosis.

Retraction: Ultrasonic irradiation and SonoVue microbubbles-mediated RNA interfering targeting PRR11 inhibits breast cancer cells proliferation and metastasis but promotes apoptosis.

Exosome-mediated transfer of lncRNA RP3-340B19.3 promotes the progression of breast cancer by sponging miR-4510/MORC4 axis

BackgroundThis study aims to explore the molecular mechanism of lncRNA RP3-340B19.3 on breast cancer cell proliferation and metastasis and clinical significance of lncRNA RP3-340B19.3 for breast cancer.MethodsThe subcellular localization of lncRNA RP3-340B19.3 was identified using RNA fluorescence in situ hybridization (FISH). The expression of lncRNA RP3-340B19.3 in breast cancer cells, breast cancer tissues, as well as the serum and serum exosomes of breast cancer patients, was measured through quantitative RT-PCR. In the in vitro setting, we conducted experiments to observe the effects of RP3-340B19.3 on both cell migration and proliferation. This was achieved through the utilization of transwell migration assays as well as clone formation assays. Meanwhile, transwell migration assays and clone formation assays were used to observe the effects of MDA-MB-231-exosomes enriched in RP3-340B19.3 on breast cancer microenvironment cells MCF7 and BMMSCs. Additionally, western blotting techniques were used to assess the expression levels of proteins associated with essential cellular processes such as proliferation, apoptosis, and metastasis. In vivo, the impact of RP3-340B19.3 knockdown on tumour weight and volume was observed within a nude mice model. We aimed to delve into the intricate molecular mechanisms involving RP3-340B19.3 by using bioinformatics analysis, dual luciferase reporter gene experiments and western blotting. Moreover, the potential correlations between RP3-340B19.3 expression and various clinical pathological characteristics were analyzed.ResultsOur investigation revealed that RP3-340B19.3 was expressed in both the cytoplasm and nucleus, with a noteworthy increase in breast cancer cells. Notably, we found that RP3-340B19.3 exerted a promoting influence on the proliferation and migration of breast cancer cells, both in vitro and in vivo. MDA-MB-231-exosomes enriched in RP3-340B19.3 promoted the proliferation and migration of MCF7 and BMMSCs in vitro. Mechanistically, RP3-340B19.3 demonstrated the capability to modulate the expression of MORC4 by forming a complex with miR-4510. This interaction subsequently triggered the activation of the NF-κB and Wnt-β-catenin signaling pathways. Furthermore, our study highlighted the potential diagnostic utility of RP3-340B19.3. We discovered its presence in the serum and exosomes of breast cancer patients, showing promising efficacy as a diagnostic marker. Notably, the diagnostic potential of RP3-340B19.3 was particularly significant in relation to distinguishing between different pathological types of breast cancer and correlating with tumour diameter.ConclusionOur findings establish that RP3-340B19.3 plays a pivotal role in driving the proliferation and metastasis of breast cancer. Additionally, exosomes enriched in RP3-340B19.3 could influence MCF7 and BMMSCs in tumour microenvironment, promoting the progression of breast cancer. This discovery positions RP3-340B19.3 as a prospective novel candidate for a tumour marker, offering substantial potential in the realms of breast cancer diagnosis and treatment strategies.

A Fungicide, Fludioxonil, Formed the Polyploid Giant Cancer Cells and Induced Metastasis and Stemness in MDA-MB-231 Triple-Negative Breast Cancer Cells.

Fludioxonil, an antifungal agent used as a pesticide, leaves a measurable residue in fruits and vegetables. It has been identified to cause endocrine disruption, interrupt normal development, and cause various diseases such as cancers. In this study, fludioxonil was examined for its effects on the development and metastasis of breast cancer cells. On fludioxonil exposure (10-5 M) for 72 h, mutant p53 (mutp53) MDA-MB-231 triple-negative breast cancer (TNBC) cells significantly inhibited cell viability and developed into polyploid giant cancer cells (PGCCs), with an increase in the number of nuclei and expansion in the cell body size. Fludioxonil exposure disrupted the normal cell cycle phase ratio, resulting in a new peak. In addition, PGCCs showed greater motility than the control and were resistant to anticancer drugs, i.e., doxorubicin, cisplatin, and 5-fluorouracil. Cyclin E1, nuclear factor kappa B (NF-κB), and p53 expressions were remarkably increased, and the expression of cell cycle-, epithelial-mesenchymal-transition (EMT)-, and cancer stemness-related proteins were increased in the PGCCs. The daughter cells obtained from PGCCs had the single nucleus but maintained their enlarged cell size and showed greater cell migration ability and resistance to the anticancer agents. Consequently, fludioxonil accumulated Cyclin E1 and promoted the inflammatory cytokine-enriched microenvironment through the up-regulation of TNF and NF-κB which led to the transformation to PGCCs via abnormal cell cycles such as mitotic delay and mitotic slippage in mutp53 TNBC MDA-MB-231 cells. PGCCs and their daughter cells exhibited significant migration ability, chemo-resistance, and cancer stemness. These results strongly suggest that fludioxonil, as an inducer of potential genotoxicity, may induce the formation of PGCCs, leading to the formation of metastatic and stem cell-like breast cancer cells.

The role of RRS1 in breast cancer cells metastasis and AEG-1/AKT/c-Myc signaling pathway.

Breast cancer is the most common malignant tumor in women. Recurrence, metastasis, and chemotherapy resistance are the main causes of death in breast cancer patients. The inhibition of breast cancer metastasis is of great significance for prolonging its survival. Ribosome biogenesis regulatory protein homolog (RRS1) is overexpressed in breast cancer tissues and is involved in regulating the carcinogenic process of breast cancer cells. However, the exact signaling pathway and molecular mechanism of RRS1 promoting breast cancer metastasis are not fully understood. Hence, the primary objective of our study is to investigate the correlation between RRS1 and breast cancer metastasis. Bioinformatic analysis was used to identify the expression levels and prognostic significance of RRS1 in breast cancer. Lenti-sh RRS1 lentivirus was constructed and employed to downregulate the RRS1 expression in MDA-MB-231 and BT549 cells, which had a high-level expression of RRS1. Subsequently, we assessed the impact of RRS1 downregulation on the proliferation, migration, and invasion of breast cancer cells using CCK-8, apoptosis, and cell cycle by flow cytometry, wound healing test, Transwell migration, and invasion experiments. Moreover, we utilized an in vivo imaging system to examine the metastatic potential of breast cancer cells after RRS1 knockdown. Picrate staining and hematoxylin-eosin staining were employed to evaluate the presence of metastatic lesions. To gain a deeper understanding of the molecular mechanism, we conducted co-immunoprecipitation and western blot. The significant overexpression of RRS1 in breast cancer indicates a worse prognosis, as determined through TCGA databases (p<0.01). Additionally, RRS1 exhibits upregulation in breast cancer (p<0.001), which is tightly linked to the occurrence of lymph node metastasis (p<0.001). Clinical breast cancer tissues and breast cancer cell lines also demonstrated a noteworthy upregulation of RRS1 (p<0.05). Loss-of-function experiment illustrated that the inhibiting of RRS1 expression reduced the rapid proliferation capacity of MDA-MB-231 and BT549 cells and hindered their migration and invasion capabilities (p<0.05). Importantly, the suppression of RRS1 significantly diminished lung metastasis in Balb/c nude mice that were injected with MDA-MB-231 cells (p<0.01). Mechanistically, RRS1 may interact with the AEG-1 to modulate the phosphorylation of AKT at T308 and S473, consequently impeding the activity of c-Myc (p<0.05). To conclude, RRS1 functions as a potential oncogene in breast cancer by leveraging the AEG-1/AKT/c-Myc signaling.

Phytochemical Identification and Assessment of Amberboa ramosa Mediated Inhibition of Microtubule and EGFR Associated Growth and Metastasis of Breast Cancer Cells: In Vitro and In Silico Perspective

Amberboa ramosa Roxb. (Asteraceae), commonly known as “Badaward”, has been used for the treatment of tumors from ancient times. In this study, we aimed to scientifically authenticate the use of A. ramosa for breast cancer treatment. The whole plant fractions of A. ramosa were evaluated for their cytotoxic properties against MDA-MB-231 breast cancer cell lines. Among these fractions, Pet. ether, ethyl acetate, and ethanolic fractions exhibited considerable levels of cytotoxicity against MDA-MB-231 cells with [Formula: see text] values of 78.55, 90.60, and 92.92 [Formula: see text]g/mL, respectively. The cell migration significantly decreased in ethyl acetate and ethanolic fractions. GC–MS was used to analyze the phytochemical profile of bioactive fractions, which revealed the presence of long-chain hydrocarbons, carboxylic acids, esters, alcohols, and terpenoids. Subsequently, the 96 compounds present in bioactive fractions were efficiently docked with EGFR and microtubule protein to evaluate affinity towards the targets. Eight common compounds were achieved using a docking-based approach against both target proteins, which showed similar interaction patterns as the reference inhibitors (colchicine and erlotinib). The key interactions revealed the potential of screened compounds as promising hits. 2-[1,2-Dihydroxyethyl]-9-[[Formula: see text]-d-ribofuranosyl]hypoxanthine showed the best dock score of −9.337 and −8.548 kcal/mol against EGFR and microtubule, respectively. 5-Oxo-cystofuranoquinol exhibited better dock score as well as binding energy against both targets. Chemical features present in the 08 dual inhibitors were also matched from the present EGFR and microtubule inhibitors for comparing the anticancer potential. Thus, this research revealed many new directions for developing natural lead compounds from Amberboa ramosa as dual inhibitors for treating breast cancer.

Pharmacological Inhibition of Necroptosis Promotes Human Breast Cancer Cell Proliferation and Metastasis [Retraction

Pharmacological Inhibition of Necroptosis Promotes Human Breast Cancer Cell Proliferation and Metastasis [Retraction

A Novel Class I HDAC Inhibitor, AW01178, Inhibits Epithelial-Mesenchymal Transition and Metastasis of Breast Cancer.

Epithelial-mesenchymal transition (EMT) refers to the transformation of polar epithelial cells into motile mesenchymal cells under specific physiological or pathological conditions, thus promoting the metastasis of cancer cells. Epithelial cadherin (E-cadherin) is a protein that plays an important role in the acquisition of tumor cell motility and serves as a key EMT epithelial marker. In the present study, AW01178, a small-molecule compound with potential therapeutic efficacy, was identified via in-cell Western high-throughput screening technology using E-cadherin as the target. The compound induced the upregulation of E-cadherin at both mRNA and protein levels and inhibited the EMT of breast cancer cells in vitro as well as metastasis in vivo. Mechanistically, AW01178 is a novel benzacetamide histone deacetylase inhibitor (HDACi) mainly targeting class I histone deacetylases. AW01178 promoted the transcription and expression of E-cadherin through enhancing the acetylation level of histone H3 in the E-cadherin promoter region, thereby inhibiting the metastasis of breast cancer cells. The collective findings support the potential utility of the novel HDACi compound identified in this study, AW01178, as a therapeutic drug for breast cancer and highlight its value for the future development of HDACi structures as anticancer drugs.

The adhesion-GPCR ADGRF5 fuels breast cancer progression by suppressing the MMP8-mediated antitumorigenic effects

ADGRF5 (GPR116) has been identified as a facilitator of breast cancer cell migration and metastasis, yet the underlying mechanisms remain largely elusive. Our current study reveals that the absence of ADGRF5 in breast cancer cells impairs extracellular matrix (ECM)-associated cell motility and impedes in vivo tumor growth. This correlates with heightened expression of matrix metalloproteinase 8 (MMP8), a well-characterized antitumorigenic MMP, and a shift in the polarization of tumor-associated neutrophils (TANs) towards the antitumor N1 phenotype in the tumor microenvironment (TME). Mechanistically, ADGRF5 inhibits ERK1/2 activity by enhancing RhoA activation, leading to decreased phosphorylation of C/EBPβ at Thr235, hindering its nuclear translocation and subsequent activation. Crucially, two C/EBPβ binding motifs essential for MMP8 transcription are identified within its promoter region. Consequently, ADGRF5 silencing fosters MMP8 expression and CXCL8 secretion, attracting increased infiltration of TANs; simultaneously, MMP8 plays a role in decorin cleavage, which leads to trapped-inactivation of TGF-β in the TME, thereby polarizing TANs towards the antitumor N1 neutrophil phenotype and mitigating TGF-β-enhanced cell motility in breast cancer. Our findings reveal a novel connection between ADGRF5, an adhesion G protein-coupled receptor, and the orchestration of the TME, which dictates malignancy progression. Overall, the data underscore ADGRF5 as a promising therapeutic target for breast cancer intervention.

RETRACTED: Hemiprotonic ph-ph+ with two targets inhibits metastatic breast cancer and concurrent candidiasis

Concurrent infection in breast cancer patients is the direct cause of the high mortality rate of the disease. However, there is no available method to increase the survival rate until now. To address the problem, we propose one drug with two target strategy to treat the refractory disease. A small chemical, ph-ph+, was attempted to be used in the study to explore the feasibility of the approach in anticancer and antifungus at the same time. The results showed that ph-ph+ could prevent the proliferation and metastasis of breast cancer cells, and kill C. albicans simultaneously. The molecular mechanism was associated with the activation of an evolutionarily conserved protease CLpP in the cancer and C. albicans cells. Also, the signaling pathway mediated by PLAGL2 that highly expressed in cancer cells participated in preventing cell metastasis and inducing apoptosis of ph-ph+. The one drug with dual targets inhibited the growth and metastasis of the cancer cells, and meanwhile eliminated C. albicans in tissues in the experimental animals. The results suggested that ph-ph+ with dual targets of CLpP and PLAGL2 would be a feasible approach to prolong the survival rate in patients with metastatic breast cancer and pathogenic infection.

NRF3 suppresses the metastasis of triple-negative breast cancer cells by inhibiting ERK activation in a ROS-dependent manner.

Our previous study demonstrated that NRF3 (NFE2L3, Nuclear Factor-erythroid 2-related factor 3) could suppress cell metastasis and proliferation in breast cancer. In this study, we investigated the mechanisms underlying its function in breast cancer. In the present study, NRF3 expression and its clinical characteristics in breast cancer were analyzed using public datasets and clinical specimens. After breast cancer cells were overexpressed NRF3, FACS was used to detect the intracellular ROS levels. The migration and invasion activities of NRF3-ectopic expressed breast cancer cells were determined by transwell assay. To validate the role of ROS/ERK axis in the inhibitory effect of NRF3 in cell metastasis, ROS scavenger NAC was also included. We found that NRF3 mRNA was highly expressed, while NRF3 protein was extremely lowly expressed in breast cancer tissues compared with their normal counterparts, and low level NRF3 was associated with poorer prognosis in patients with triple negative breast cancer (TNBC). More interestingly, overexpression of NRF3 protein significantly increased cellular ROS production and dramatically decreased p-ERK level and cell migration in TNBC cells. Mechanistically, NRF3 protein was found to be mutually regulated by valosin-containing protein (VCP). Strikingly, VCP-knockdown dramatically increased NRF3 protein expression, but NRF3-knockin also decreased VCP expression in return. Moreover, antioxidant NAC treatment effectively increased the level of p-ERK and VCP expression, as well as cell migration and invasion abilities of TNBC cells. NRF3, a tumor suppressor downregulated by VCP, could attenuate cell metastasis in TNBC cells by increasing cellular ROS accumulation and subsequently inhibiting the ERK phosphorylation.

KCNK1 promotes proliferation and metastasis of breast cancer cells by activating lactate dehydrogenase A (LDHA) and up-regulating H3K18 lactylation.

Breast cancer is the most prevalent malignancy and the most significant contributor to mortality in female oncology patients. Potassium Two Pore Domain Channel Subfamily K Member 1 (KCNK1) is differentially expressed in a variety of tumors, but the mechanism of its function in breast cancer is unknown. In this study, we found for the first time that KCNK1 was significantly up-regulated in human breast cancer and was correlated with poor prognosis in breast cancer patients. KCNK1 promoted breast cancer proliferation, invasion, and metastasis in vitro and vivo. Further studies unexpectedly revealed that KCNK1 increased the glycolysis and lactate production in breast cancer cells by binding to and activating lactate dehydrogenase A (LDHA), which promoted histones lysine lactylation to induce the expression of a series of downstream genes and LDHA itself. Notably, increased expression of LDHA served as a vicious positive feedback to reduce tumor cell stiffness and adhesion, which eventually resulted in the proliferation, invasion, and metastasis of breast cancer. In conclusion, our results suggest that KCNK1 may serve as a potential breast cancer biomarker, and deeper insight into the cancer-promoting mechanism of KCNK1 may uncover a novel therapeutic target for breast cancer treatment.

Identification of GNB1 as a downstream effector of the circRNA-0133711/miR-145-5p axis involved in breast cancer proliferation and metastasis

Abstract Objectives Despite the involvement of the G protein beta-1 (GNB1) protein in various cancer types, its relationship to breast tumours is presently uncertain. This research focused on the expression of GNB1 in breast cancer and its possible biological ramifications in an effort to explain this confusion. Methods The expression levels of GNB1 in adjacent normal tissues and breast cancer were compared. We next constructed GNB1-overexpressed or -knockdown MDA-MB-231 cell lines in order to clarify GNB1’s function in breast cancer. We used colony-formation assays, CCK-8 assays, xenograft models, and transwell migration/invasion assays to evaluate the effect of GNB1 on tumorigenicity, migration, and invasion. Moreover, we used western blot analysis to investigate the significance of FAK/mTOR signalling in GNB1-regulated tumour stimulatory effects in breast cancer. Finally, we investigated the upstream regulatory signaling of GNB1 using luciferase reporter and functional repair assays. Results When comparing human breast cancer specimens to specimens of normal tissue, we discovered that GNB1 was noticeably overexpressed. This phenotype was also found to be substantially associated with unfavourable clinical outcomes. Functional research findings indicate that elevated expression of GNB1 stimulated the proliferation and metastasis of breast cancer cells. Additionally, we discovered that GNB1 activated the FAK/mTOR signalling cascade by directly inducing the phosphorylation of the FAK protein through specific contacts. According to the results of the RNA pull-down assays and dual-luciferase reporter, we concluded that circRNA-0133711 functions as a competitive endogenous RNA (ceRNA) that sequesters miR-145-5p and thereby relieves its repressive effect on GNB1 expression. Conclusions Collectively, our research findings elucidate the hitherto unexplored important role of the circRNA-0133711/miR-145-5p/GNB1 axis in the formation of breast cancer, and provide a new biomarker for clinical diagnosis and treatment of breast cancer.

LncRNA OIP5-AS1 Upregulates the Cyclin D2 Levels to Promote Metastasis of Breast Cancer by Targeting miR-150-5p.

Breast cancer (BC) is a cancer that seriously affects women's health. BC cell migration increases the mortality of BC patients. Current studies have shown that long noncoding RNAs (LncRNAs) are related to the metastasis mechanism of BC. This study aimed to explore the function and role of LncRNA OIP5-AS1 in BC. And we analyzed its regulatory mechanism and related modification process. Our study analyzed the expression pattern of OIP5-AS1 in BC tissues and cell lines by qRT-PCR. The effects of OIP5-AS1 on the function of BC cells were detected by CCK-8 and transwell experiments. Bioinformatics analysis and double luciferase reporter gene detection were used to confirm the correlation between OIP5-AS1 and miR-150-5p and between miR-150-5p and Cyclin D2 (CCND2). The rescue test analyzed the effect of miR-150-5p regulating OIP5-AS1. In addition, the N6-methyladenosine (m6A) modification process of OIP5-AS1 was analyzed by RNA m6A dot blot, RIP assay, and double luciferase report experiment. OIP5-AS1 was significantly upregulated in BC tissues and cell lines. OIP5-AS1 knockdown inhibited BC cell viability, migration and invasion. OIP5-AS1 upregulated CCND2 by binding with miR-150-5p. This process affected the metastasis of BC. Higher degree of m6A methylation was confirmed in BC cell lines. There were some binding sites between methyltransferase like 3 (METTL3) and OIP5-AS1. Moreover, the silencing of METTL3 inhibited the OIP5-AS1 expression through decreasing the m6A methylation levels. LncRNA OIP5-AS1 promoted cell viability and metastasis of BC cells by targeting miR-150-5p/CCND2 axis. This process was modified by m6A methylation of METTL3.

MicroRNA-1205 promotes breast cancer cell metastasis by regulating epithelial-to-mesenchymal transition via targeting of CDK3

Metastasis poses a huge obstacle to the survival of breast cancer patients. The microRNA miR-1205 acts as a tumor suppressor in various cancers, but its roles in breast cancer and metastasis remain unclear. To elucidate its function in breast cancer progression, we analyzed miR-1205 expression in human tumor samples and carried out a series of functional studies in in vitro and in vivo. miR-1205 was expressed more highly in metastatic breast tumor samples than in non-metastatic samples and was associated with lymph node metastasis, clinical stage, and poor prognosis. Moreover, miR-1205 promoted breast cancer cell invasiveness in vitro and metastasis in mice by directly targeting CDK3 and reducing CDK3 protein levels. We also showed that CDK3 interacts with Snail protein, inducing Snail degradation via the ubiquitin-proteasome system and potentially affecting epithelial-to-mesenchymal transition. Furthermore, analysis of clinical tissue samples indicated that CDK3 and miR-1205 levels were inversely correlated in lymph node metastasis-positive primary tumors. This study demonstrated the pro-metastatic role of miR-1205 in breast cancer, mediated via a novel miR-1205/CDK3/Snail axis. Moreover, we identified miR-1205 and CDK3 as potential markers of invasion and progression in breast cancer.