Aggressive Breast Cancer Research Articles

Antioxidant Properties of Lippia alba Essential Oil: A Potential Treatment for Oxidative Stress-Related Conditions in Plants and Cancer Cells.

Lippia alba (Mill.) N.E.Br. ex Britton and P. Wilson is used in folk medicine of Central and South America for its biological activities: i.e., antifungal, antibacterial, antiviral, and anti-inflammatory. Based on ethnopharmacological information and the increasing interest in this species, this work aimed to test a possible wide use of its essential oil (EO) in pharmaceutical and horticultural applications. Therefore, we focused the attention on the antioxidant activity of the oil as a possible tool to overcome the oxidative stress in both applications. For this purpose, we have chosen three aggressive breast cancer cell lines and two horticultural species (Solanum lycopersicum L. and Phaseolus acutifolius L.) that are very sensitive to salt stress. We determined the antioxidant activity of L. alba EO through the quantification of phenols and flavonoids. Regarding tomato and bean plants under salt stress, L. alba EO was used for the first time as a seed priming agent to enhance plant salt tolerance. In this case, the seed treatment enhanced the content of phenolic compounds, reduced power and scavenger activity, and decreased membrane lipid peroxidation, thus mitigating the oxidative stress induced by salt. While in breast cancer cells the EO treatment showed different responses according to the cell lines, i.e., in SUM149 and MDA-MB-231 the EO decreased proliferation and increased antioxidant activity and lipid peroxidation, showing high cytotoxic effects associated with the release of lactate dehydrogenase, vice versa no effect was observed in MDA-MB-468. Such antioxidant activity opens a new perspective about this essential oil as a possible tool to counteract proliferation in some cancer cell lines and in horticulture as a seed priming agent to protect from oxidative damage in crops sensitive to salinity.

Expanding the treatment options for HER2-low metastatic breast cancer: Experience with trastuzumab deruxtecan in aggressive luminal HER2-low breast cancer

Expanding the treatment options for HER2-low metastatic breast cancer: Experience with trastuzumab deruxtecan in aggressive luminal HER2-low breast cancer

DMF-DM-seq: Digital-Microfluidics Enabled Dual-Modality Sequencing of Single-Cell mRNA and microRNA with High Integration, Sensitivity, and Automation.

Multimodal measurement of single cells provides deep insights into the intricate relationships between individual molecular layers and the regulatory mechanisms underlying intercellular variations. Here, we reported DMF-DM-seq, a highly integrated, sensitive, and automated platform for single-cell mRNA and microRNA (miRNA) co-sequencing based on digital microfluidics. This platform first integrates the processes of single-cell isolation, lysis, component separation, and simultaneous sequencing library preparation of mRNA and miRNA within a single DMF device. Compared with the current half-cell measuring strategy, DMF-DM-seq enables complete separation of single-cell mRNA and miRNA via a magnetic field application, resulting in a higher miRNA detection ability. DMF-DM-seq revealed differential expression patterns of single cells of noncancerous breast cells and noninvasive and aggressive breast cancer cells at both mRNA and miRNA levels. The results demonstrated the anticorrelated relationship between miRNA and their mRNA targets. Further, we unravel the tumor growth and metastasis-associated biological processes enriched by miRNA-targeted genes, along with important miRNA-interaction networks involved in significant signaling pathways. We also deconstruct the miRNA regulatory mechanisms underlying different signaling pathways across different breast cell types. In summary, DMF-DM-seq offers a powerful tool for a comprehensive study of the expression heterogeneity of single-cell mRNA and miRNA, which will be widely applied in basic and clinical research.

MAZ-mediated up-regulation of BCKDK reprograms glucose metabolism and promotes growth by regulating glucose-6-phosphate dehydrogenase stability in triple-negative breast cancer

Tumour metabolic reprogramming is pivotal for tumour survival and proliferation. Investigating potential molecular mechanisms within the heterogeneous and clinically aggressive triple-negative breast cancer (TNBC) subtype is essential to identifying novel therapeutic targets. Accordingly, we investigated the role of branched-chain α-keto acid dehydrogenase kinase (BCKDK) in promoting tumorigenesis in TNBC. We analysed The Cancer Genome Atlas dataset and immunohistochemically stained surgical specimens to investigate BCKDK expression and its prognostic implications in TNBC. The effects of BCKDK on tumorigenesis were assessed using cell viability, colony formation, apoptosis, and cell cycle assays, and subsequently validated in vivo. Metabolomic screening was performed via isotope tracer studies. The downstream target was confirmed using mass spectrometry and a co-immunoprecipitation experiment coupled with immunofluorescence analysis. Upstream transcription factors were also examined using chromatin immunoprecipitation and luciferase assays. BCKDK was upregulated in TNBC tumour tissues and associated with poor prognosis. BCKDK depletion led to reduced cell proliferation both in vitro and vivo. MYC-associated zinc finger protein (MAZ) was confirmed as the major transcription factor directly regulating BCKDK expression in TNBC. Mechanistically, BCKDK interacted with glucose-6-phosphate dehydrogenase (G6PD), leading to increased flux in the pentose phosphate pathway for macromolecule synthesis and detoxification of reactive oxygen species. Forced expression of G6PD rescued the growth defect in BCKDK-deficient cells. Notably, the small-molecule inhibitor of BCKDK, 3,6-dichlorobenzo(b)thiophene-2-carboxylic acid, exhibited anti-tumour effects in a patient-derived tumour xenograft model. Our findings hold significant promise for developing targeted therapies aimed at disrupting the MAZ/BCKDK/G6PD signalling pathway, offering potential advancements in treating TNBC through metabolic reprogramming.

Ivermectin Synergizes with Modulated Electro-hyperthermia and Improves Its Anticancer Effects in a Triple-Negative Breast Cancer Mouse Model.

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, with limited treatment options. Modulated electro-hyperthermia (mEHT) is a novel adjuvant cancer therapy that induces selective cancer damage. However, mEHT upregulates heat shock protein beta 1 (HSPB1), a cancer-promoting stress chaperone molecule. Thus, we investigated whether ivermectin (IVM), an anthelmintic drug, may synergize with mEHT and enhance its anticancer effects by inhibiting HSPB1 phosphorylation. Isogenic 4T1 TNBC cells were inoculated into BALB/c mice and treated with mEHT, IVM, or a combination of both. IVM synergistically improved the tumor growth inhibition achieved by mEHT. Moreover, IVM downregulated mEHT-induced HSPB1 phosphorylation. Thus, the strongest cancer tissue damage was observed in the mEHT + IVM-treated tumors, coupled with the strongest apoptosis induction and proliferation inhibition. In addition, there was no significant body weight loss in mice treated with mEHT and IVM, indicating that this combination was well-tolerated. In conclusion, mEHT combined with IVM is a new, effective, and safe option for the treatment of TNBC.

In vivo spectroscopy to concurrently characterize five metabolic and vascular endpoints relevant to aggressive breast cancer

In vivo spectroscopy to concurrently characterize five metabolic and vascular endpoints relevant to aggressive breast cancer

Beyond Triple-Negative: High Prevalence of Quadruple-Negative Breast Cancer in African Americans.

Quadruple-negative breast cancer (QNBC) is a triple-negative breast cancer (TNBC) subtype that lacks expression of the androgen (AR) receptor. Few studies have focused on this highly aggressive breast cancer, portending worse survival rates. We aimed to determine the following: (1) QNBC's molecular and clinical characteristics and compare them with other subtypes and (2) QNBC's association with clinicopathological factors and prognostic markers. We performed immunohistochemical evaluations of ARs on tissue tumor microarrays from FFPE tumor blocks of invasive ductal breast carcinomas in 202 African American women. Univariate analysis was performed using the chi-square test, with survival rates calculated using Kaplan-Meier curves. Overall, 75.8% of TNBCs were AR-negative. Compared to the luminal subtypes, TNBC and QNBC tumors were likely to be a higher grade (p < 0.001); HER2+/AR- and QNBCs were also larger than the other subtypes (p < 0.001). They also expressed increasing mean levels of proteins involved in invasion, such as CD44, fascin, and vimentin, as well as decreasing the expression of proteins involved in mammary differentiation, such as GATA3 and mammaglobin. We found no association between QNBC and stage, recurrence-free survival, or overall survival rates. The high prevalence of TNBC AR-negativity in these women could explain observed worse outcomes, supporting the existence of the unique QNBC subtype.

Isosteric Replacement of Sulfur to Selenium in a Thiosemicarbazone: Promotion of Zn(II) Complex Dissociation and Transmetalation to Augment Anticancer Efficacy.

We implemented isosteric replacement of sulfur to selenium in a novel thiosemicarbazone (PPTP4c4mT) to create a selenosemicarbazone (PPTP4c4mSe) that demonstrates potentiated anticancer efficacy and selectivity. Their design specifically incorporated cyclohexyl and styryl moieties to sterically inhibit the approach of their Fe(III) complexes to the oxy-myoglobin heme plane. Importantly, in contrast to the Fe(III) complexes of the clinically trialed thiosemicarbazones Triapine, COTI-2, and DpC, the Fe(III) complexes of PPTP4c4mT and PPTP4c4mSe did not induce detrimental oxy-myoglobin oxidation. Furthermore, PPTP4c4mSe demonstrated more potent antiproliferative activity than the homologous thiosemicarbazone, PPTP4c4mT, with their selectivity being superior or similar, respectively, to the clinically trialed thiosemicarbazone, COTI-2. An advantageous property of the selenosemicarbazone Zn(II) complexes relative to their thiosemicarbazone analogues was their greater transmetalation to Cu(II) complexes in lysosomes. This latter effect probably promoted their antiproliferative activity. Both ligands down-regulated multiple key receptors that display inter-receptor cooperation that leads to aggressive and resistant breast cancer.

TWEAK/Fn14 signalling driven super-enhancer reprogramming promotes pro-metastatic metabolic rewiring in triple-negative breast cancer

Triple Negative Breast Cancer (TNBC) is the most aggressive breast cancer subtype suffering from limited targeted treatment options. Following recent reports correlating Fibroblast growth factor-inducible 14 (Fn14) receptor overexpression in Estrogen Receptor (ER)-negative breast cancers with metastatic events, we show that Fn14 is specifically overexpressed in TNBC patients and associated with poor survival. We demonstrate that constitutive Fn14 signalling rewires the transcriptomic and epigenomic landscape of TNBC, leading to enhanced tumour growth and metastasis. We further illustrate that such mechanisms activate TNBC-specific super enhancers (SE) to drive the transcriptional activation of cancer dependency genes via chromatin looping. In particular, we uncover the SE-driven upregulation of Nicotinamide phosphoribosyltransferase (NAMPT), which promotes NAD+ and ATP metabolic reprogramming critical for filopodia formation and metastasis. Collectively, our study details the complex mechanistic link between TWEAK/Fn14 signalling and TNBC metastasis, which reveals several vulnerabilities which could be pursued for the targeted treatment of TNBC patients.

The Role of Melatonin and Matrix Metalloproteinases in Breast Cancer Pathogenesis: A Comprehensive Review

Background: Breast cancer is a heterogeneous disease with molecular subtypes including Triple Negative Breast Cancer (TNBC), HER2/neu-positive, Luminal Type A, and Luminal Type B, each with unique clinical behaviors and therapeutic responses. This study investigates the role of melatonin, matrix metalloproteinases (MMPs), pro-inflammatory cytokines (IL6 and TNF-alpha), and lactate dehydrogenase (LDH) isoenzymes in breast cancer pathogenesis. Methods: Over three years, 171 breast cancer patients were studied. Blood and urine samples were collected to measure melatonin, MMPs, IL-6, TNF-alpha, LDH-1, and LDH-5 levels. Circulating tumor cells (CTCs) were isolated using density gradient centrifugation and immunomagnetic separation. Melatonin receptor expression on CTCs was analyzed by flow cytometry and immunocytochemistry. Plasma concentrations of melatonin were measured using high-performance liquid chromatography (HPLC), and MMPs, IL-6, TNF-alpha, LDH isoenzymes were quantified using enzyme-linked immunosorbent assays (ELISAs) and electrophoretic methods. Results: The expression of melatonin receptors was lowest in TNBC patients, higher in HER2/neu-positive and ER/PRnegative patients, and highest in Luminal Type A and B patients. TNBC patients exhibited elevated LDH-1 and inflammatory cytokines (IL-6, TNF-alpha), with significantly decreased melatonin levels. HER2/neu-positive patients showed elevated LDH5 and moderate decreases in melatonin. Luminal Type B and A patients had varying degrees of biomarker elevation and melatonin receptor expression. Discussion: The findings suggest a correlation between reduced melatonin signaling and aggressive breast cancer phenotypes, particularly TNBC. Elevated MMPs and pro-inflammatory cytokines underscore the role of inflammation and ECM degradation in cancer progression. Melatonin’s potential inhibitory effects on these pathways highlight its therapeutic promise. The combined assessment of melatonin, MMPs, cytokines, and LDH could guide personalized treatment strategies. Conclusion: This study underscores melatonin’s multifaceted role in breast cancer pathogenesis. Melatonin receptor expression, along with MMP, IL-6, TNF-alpha, and LDH levels, provides a detailed molecular landscape of breast cancer subtypes. Integrating melatonin supplementation into therapeutic regimens holds promise for improving outcomes, particularly inaggressive subtypes like TNBC. Further research and clinical trials are essential to validate these findings and develop effective melatonin-based therapies.

[Artículo traducido] Efectividad y seguridad del tratamiento neoadyuvante del cáncer de mama triple negativo en la vida real

ObjectiveTriple-negative breast cancer is a subtype of aggressive breast cancer. Our aim is to evaluate the effectiveness and safety of neoadjuvant treatment in early-stage triple-negative breast cancer and to identify predictors of pathological complete response. MethodsThis is a single-center, retrospective study involving 79 patients with triple-negative breast cancer who initiated neoadjuvant treatment between January 2017 and October 2022. Descriptive analyses were performed as appropriate. Statistical analysis utilized bivariate logistic regression to explore the presence of factors related to pathological complete response, and the Kaplan–Meier method was employed for survival analysis. ResultsIn the overall population, 27 patients (n = 78; 34.6%) achieved pathological complete response in the breast and axillary lymph nodes, and 31 (n = 73; 42.5%) achieved a grade 5 pathological complete response in the breast, according to the Miller and Payne classification. The addition of platinum to standard therapy improved both breast and axillary lymph node pathological complete response rates. Age less than 40 years was identified as a predictor of pathological complete response in our study population through bivariate analysis, while Ki67 levels lower than 70% were associated with a lower pathological complete response rate. Adverse events were reported in 72 patients (91.1%), with grade 3–5 adverse events observed in 33 (41.8%). There was a particularly notable increase in gastrointestinal and hematological adverse events when platinum was added. ConclusionsIn this population, we observed moderate rates of pathological complete response with acceptable chemotherapy tolerance. Platinum-based chemotherapy appears to enhance the likelihood of achieving pathological complete response, albeit with a less favorable safety profile. Therefore, evaluating the benefit–risk balance is crucial when selecting the optimal chemotherapy regimen for individual patients.

Baohuoside I chemosensitises breast cancer to paclitaxel by suppressing extracellular vesicle/CXCL1 signal released from apoptotic cells.

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype and chemotherapy is the cornerstone treatment for TNBC. Regrettably, emerging findings suggest that chemotherapy facilitates pro-metastatic changes in the tumour microenvironment. Extracellular vesicles (EVs) have been highly implicated in cancer drug resistance and metastasis. However, the effects of the EVs released from dying cancer cells on TNBC prognosis and corresponding therapeutic strategies have been poorly investigated. This study demonstrated that paclitaxel chemotherapy elicited CXCL1-enriched EVs from apoptotic TNBC cells (EV-Apo). EV-Apo promoted the chemoresistance and invasion of co-cultured TNBC cells by polarizing M2 macrophages through activating PD-L1 signalling. However, baohuoside I (BHS) remarkably sensitized the co-cultured TNBC cells to paclitaxel chemotherapy via modulating EV-Apo signalling. Mechanistically, BHS remarkably decreased C-X-C motif chemokine ligand 1 (CXCL1) cargo within EV-Apo and therefore attenuated macrophage M2 polarization by suppressing PD-L1 activation. Additionally, BHS decreased EV-Apo release by diminishing the biogenesis of intraluminal vesicles (ILVs) within multivesicular bodies (MVBs) of TNBC cells. Furthermore, BHS bound to the LEU104 residue of flotillin 2 (FLOT2) and interrupted its interaction with RAS oncogene family member 31 (RAB31), leading to the blockage of RAB31-FLOT2 complex-driven ILV biogenesis. Importantly, BHS remarkably chemosensitised paclitaxel to inhibit TNBC metastasis in vivo by suppressing EV-ApoCXCL1-induced PD-L1 activation and M2 polarization of tumour-associated macrophages (TAMs). This pioneering study sheds light on EV-ApoCXCL1 as a novel therapeutic target to chemosensitise TNBC, and presents BHS as a promising chemotherapy adjuvant to improve TNBC chemosensitivity and prognosis by disturbing EV-ApoCXCL1 biogenesis.

NDRG1 acts as an oncogene in triple-negative breast cancer and its loss sensitizes cells to mitochondrial iron chelation.

Multiple studies indicate that iron chelators enhance their anti-cancer properties by inducing NDRG1, a known tumor and metastasis suppressor. However, the exact role of NDRG1 remains controversial, as newer studies have shown that NDRG1 can also act as an oncogene. Our group recently introduced mitochondrially targeted iron chelators deferoxamine (mitoDFO) and deferasirox (mitoDFX) as effective anti-cancer agents. In this study, we evaluated the ability of these modified chelators to induce NDRG1 and the role of NDRG1 in breast cancer. We demonstrated that both compounds specifically increase NDRG1 without inducing other NDRG family members. We have documented that the effect of mitochondrially targeted chelators is at least partially mediated by GSK3α/β, leading to phosphorylation of NDRG1 at Thr346 and to a lesser extent on Ser330. Loss of NDRG1 increases cell death induced by mitoDFX. Notably, MDA-MB-231 cells lacking NDRG1 exhibit reduced extracellular acidification rate and grow slower than parental cells, while the opposite is true for ER+ MCF7 cells. Moreover, overexpression of full-length NDRG1 and the N-terminally truncated isoform (59112) significantly reduced sensitivity towards mitoDFX in ER+ cells. Furthermore, cells overexpressing full-length NDRG1 exhibited a significantly accelerated tumor formation, while its N-terminally truncated isoforms showed significantly impaired capacity to form tumors. Thus, overexpression of full-length NDRG1 promotes tumor growth in highly aggressive triple-negative breast cancer.

Effect of microRNA-141-3p, E2F3, CDK3, and KAT2B overexpression on histologic tumor grade and metastasis status in untreated breast cancer tissues

Introduction: Increasing evidence has reported gene expression alterations in breast cancer (BC) tissues, necessitating their investigating to highlight the molecular basis of the disease development or progression. This study investigated the expression of miR-141, E2F3, CDK3, TP53, and KAT2B, and their association with histologic grade and metastasis in BC tissues. Methods: The RNA expression level of miR-141, E2F3, CDK3, TP53, and KAT2B genes was analyzed in 23 BC and 23 normal tissue samples by RT-qPCR. The associations of the expression level of these genes with clinicopathological features of the BC tissue samples were evaluated. The study also explored the correlation between RNA levels of genes and miR-141. Results: Expression of miR-141, E2F3, CDK3, and KAT2B demonstrated significantly higher levels in BC tumor than normal tissues. TP53 expression showed an increase in tumor compared to normal tissues, although it was insignificant. Moreover, increased RNA expression of miR-141, E2F3, CDK3, and KAT2B corresponded to the advanced stage and regional metastasis of BC. Additionally, the results demonstrated a significant correlation between RNA expression levels of miR-141 with CDK3 and E2F3 with KAT2B. Conclusion: Our findings highlighted clinicopathologic indicators that were relevant to aggressive BC. Besides, Correlations between overexpression of miR-141, E2F3, CDK3, and KAT2B in BC tissues suggest regulatory effects. Taken together, it seems results of this study could provide evidence that dysregulation of gene expression contributes significantly to unveiling the underlying molecular basis of BC.

AGEs induce MMP-9 promoter demethylation through the GADD45α-mediated BER pathway to promote breast cancer metastasis in patients with diabetes.

Scientific evidence has linked diabetes to a higher incidence and increased aggressiveness of breast cancer; however, mechanistic studies of the numerous regulators involved in this process are insufficiently thorough. Advanced glycation end products (AGEs) play an important role in the chronic complications of diabetes, but the mechanisms of AGEs in breast cancer are largely unexplored. In this study, we first demonstrate that high AGE levels in breast cancer tissues are associated with the diabetic state and poor patient outcomes. Furthermore, AGEs interact with the receptor for AGEs (RAGE) to promote breast cancer cell migration and invasion. Mechanistically, based on RNA sequencing (RNA-seq) analysis, we reveal that growth arrest and DNA damage gene 45α (GADD45α) is a vital protein upregulated by AGEs through a P53-dependent pathway. Next, GADD45α recruits thymine DNA glycosylase for base excision repair to form the demethylation complex at the promoter region of MMP-9 and enhance MMP-9 transactivation through DNA demethylation. Overall, our results indicate a critical regulatory role of AGEs in patients with breast cancer and diabetes and reveal a novel mechanism of epigenetic modification in promoting breast cancer metastasis.

Obesity Induces Temporally Regulated Alterations in the Extracellular Matrix That Drive Breast Tumor Invasion and Metastasis.

Obesity is associated with increased incidence and metastasis of triple-negative breast cancer, an aggressive breast cancer subtype. The extracellular matrix (ECM) is a major component of the tumor microenvironment that drives metastasis. To characterize the temporal effects of age and high-fat diet (HFD)-driven weight gain on the ECM, we injected allograft tumor cells at 4-week intervals into mammary fat pads of mice fed a control or HFD, assessing tumor growth and metastasis and evaluating the ECM composition of the mammary fat pads, lungs, and livers. Tumor growth was increased in obese mice after 12 weeks on HFD. Liver metastasis increased in obese mice only at 4 weeks, and elevated body weight correlated with increased metastasis to the lungs but not the liver. Whole decellularized ECM coupled with proteomics indicated that early stages of obesity were sufficient to induce changes in the ECM composition. Obesity led to an increased abundance of the proinvasive ECM proteins collagen IV and collagen VI in the mammary glands and enhanced the invasive capacity of cancer cells. Cells of stromal vascular fraction and adipose stem and progenitor cells were primarily responsible for secreting collagen IV and collagen VI, not adipocytes. Longer exposure to HFD increased the invasive potential of ECM isolated from the lungs and liver, with significant changes in ECM composition found in the liver with short-term HFD exposure. Together, these data suggest that changes in the breast, lungs, and liver ECM underlie some of the effects of obesity on triple-negative breast cancer incidence and metastasis. Significance: Organ-specific extracellular matrix changes in the primary tumor and metastatic microenvironment are mechanisms by which obesity contributes to breast cancer progression.

Deciphering the molecular landscape: evolutionary progression from gynecomastia to aggressive male breast cancer.

Gynecomastia denotes the benign proliferation of glandular breast tissue and stands as a recognized risk factor for male breast cancer. Nonetheless, the underlying carcinogenic mechanisms orchestrating the progression from gynecomastia to cancer remain poorly understood. This study employed single-cell RNA sequencing (scRNA-seq) to meticulously dissect the cellular landscape of gynecomastia and unravel potential associations with male breast cancer at a single-cell resolution. Pseudotime and evolutionary analyses were executed to delineate the distinct features characterizing gynecomastia and male breast cancer. The TCGA database, along with cell-cell communication analysis and immunohistochemistry staining, was harnessed to validate differential gene expression, specifically focusing on CD13. From the copy number variation profiles and evolutionary tree, we inferred shared mutation characteristics (18p+ and 18q+) underpinning both conditions. The developmental trajectory unveiled an intriguing overlap between gynecomastia and malignant epithelial cells. Moreover, the differential gene CD13 emerged as a common denominator in both gynecomastia and male breast cancer when compared with normal mammary tissue. Cell-cell interaction analysis and communication dynamics within the tumor microenvironment spotlighted distinctions between CD13+ and CD13- subsets, with the former exhibiting elevated expression of FGFR1-FGF7. Our investigation provides novel insights into the evolutionary progression from gynecomastia to male breast cancer, shedding light on the pivotal role of CD13 in driving this transition. The identification of CD13 as a potential therapeutic target suggests the feasibility of CD13-targeted interventions, specifically tailored for male breast cancer treatment.

The lncRNAMALAT1-WTAP axis: a novel layer of EMT regulation in hypoxic triple-negative breast cancer

Early metastatic disease development is one characteristic that defines triple-negative breast cancer (TNBC) as the most aggressive breast cancer (BC) subtype. Numerous studies have identified long non-coding RNAs (lncRNA) as critical players in regulating tumor progression and metastasis formation. Here, we show that MALAT1, a long non-coding RNA known to promote various features of BC malignancy, such as migration and neo angiogenesis, regulates TNBC cell response to hypoxia. By profiling MALAT1-associated transcripts, we discovered that lncRNA MALAT1 interacts with the mRNA encoding WTAP protein, previously reported as a component of the N6-methyladenosine (m6A) modification writer complex. In hypoxic conditions, MALAT1 positively regulates WTAP protein expression, which influences the response to hypoxia by favoring the transcription of the master regulators HIF1α and HIF1β. Furthermore, WTAP stimulates BC cell migratory ability and the expression of N-Cadherin and Vimentin, hallmarks of epithelial-to-mesenchymal transition (EMT). In conclusion, this study highlights the functional axis comprising MALAT1 and WTAP as a novel prognostic marker of TNBC progression and as a potential target for the development of therapeutic approaches for TNBC treatment.

Evaluation of molecular effects associated with apoptosis, tumour progression, angiogenesis and metastasis by a novel combination of drugs with ormeloxifene in triple negative breast cancer cells.

To investigate the molecular effects of a novel combination [sertraline and plumbagin (comb) with ormeloxifene (Orm)] for anticancer activity in triple negative breast cancer cell line "MDA-MB-231". The cytotoxic effect of the drugs was analyzed by the MTT assay and nuclear morphological changes by acridine orange/ethidium bromide (AO/EB) staining. Induction of apoptosis by annexin V-FITC staining, active caspase-3 detection and cell cycle analysis were studied in vitro on "MDA-MB-231" cells. The qRT-PCR was done to explore the upregulation and down regulation of targeted genes for angiogenesis, metastasis, tumor suppression and protein folding on the triple negative breast cancer cells. The preliminary anti-angiogenic effect of the drugs was assessed by chorioallantoic membrane (CAM) assay. Orm showed inhibitory effects in "MDA-MB-231" cells in a dose and time dependent manner whereas; the drugs in combination gave better cytotoxic effects in the screening MTT assay. Orm + comb was more effective than Orm alone in eliciting apoptosis as well as inhibited the single cell to grow into a colony. CAM assay using Orm and Orm + comb suggested the anti-angiogenic potential which was further confirmed by the downregulation of VEGF in "MDA-MB-231" cells by qRT-PCR studies. The combination was found to effectively upregulate the expression of P53 and P21 and downregulate the gene expression of zinc finger E-box binding homeobox 1 (ZEB1) and heat shock protein 70 (HSP70) in "MDA-MB-231" cancer cells. Collectively this study reveals the efficacy of Orm + comb as more significant than the clinically used tamoxifen (Tam). The study elucidates the promising novelty of the combination as a potential chemotherapeutic intervention for mitigating the aggressiveness of triple negative breast cancer and it addresses the intrinsic resistance caused by single drug treatments.

Rheum khorasanicum Decreases Migration and Induces Apoptosis in the MDA-MB-231 Breast Cancer Cell Line

aims: N/A background: Rheum khorasanicum belongs to the Polygonaceae family, which is well-known for its anticancer activities. objective: Due to the limited studies on the anticancer activity of R. khorasanicum, the present study aimed to evaluate the apoptotic effect of this medicinal plant on MDA-MB-231 cells as a model for an aggressive triple negative breast cancer that has lower treatment option. method: The high-performance thin layer chromatography (HPTLC) assay was used for determining the main ingredients of the extract. Viability and apoptosis of the cells was evaluated by WST-1 and the annexin-V/PI dual staining assay, respectively. The scratch assay was used to assess the cellular migratory potential, and the western blotting test was employed for determining the expression of proteins involved in the apoptotic pathway. result: The HPTLC analysis indicated that emodin, gallic acid, epicatechin gallate, and rhaponticin are pharmacologically active compounds isolated from the hydro-alcoholic extract of R. khorasanicum. The extract showed a significant toxic effect on MDA-MB-231 cells. R. khorasanicum extracts also inhibited cellular migratory potential at concentrations higher than 60 μg/mL. The plant extract significantly diminished the Bcl-2/Bax ratio and increased cleaved caspase- 3, cleaved caspase-7/ procaspase-7 expression at protein levels compared to the nontreated cells. conclusion: Our findings demonstrated that effect root extract efficiently triggered the death of breast cancer cell lines possibly through the stimulation of the apoptotic signaling pathway. other: N/A