Treatment Of Breast Cancer Cells Research Articles

Changes of intestinal microflora of breast cancer in premenopausal women.

Breast cancer is one of the most common malignant tumors in women. More than half of breast cancer patients are not menopausal at the time of diagnosis. The occurrence and development of premenopausal breast cancer are affected by many factors. Intestinal flora, especially SCFA-producing bacteria, participates in the development of various tumors, and there is a lack of in-depth research in premenopausal breast cancer patients. We used 16S rRNA gene sequencing, targeted metabolomics, and cell culture methods to analyze the changes in the intestinal flora and metabolites of premenopausal breast cancer patients. In addition, we treated breast cancer cells with significantly altered propionate and butyrate in vitro to examine their effects on cell activity. This study followed STROBE guidelines. We found that compared with healthy premenopausal women, the composition and symbiosis of intestinal flora in patients with premenopausal breast cancer changed significantly. The abundance of short-chain fatty acid (SCFA)-producing bacteria was significantly reduced, and the key SCFA-producing enzymes were also significantly reduced. Pediococcus and Desulfovibrio could distinguish premenopausal breast cancer patients from normal premenopausal women. The related propionate and butyrate had a certain ability to inhibit breast cancer cell viability in vitro. As SCFA-producing bacteria, Pediococcus and Desulfovibrio showed potential reference value for the diagnosis of premenopausal breast cancer. The ability of propionate and butyrate to inhibit breast cancer cell lines in vitro suggests that the relevant SCFA receptor may be a new target for the treatment of premenopausal breast cancer.

Abstract 4365: Estrogen receptor β agonists reverses letrozole therapy resistance of breast cancer through FOXO3 and FOXM1 mediated actions

Abstract Introduction: Breast cancer (BC) is the most common cancer in women worldwide and leading cause of cancer death. More than 70% of cancers are estrogen receptor alpha (ERα) positive. Despite effective therapeutic strategies for treating hormone receptor-positive (HR+) breast cancer, resistance to endocrine therapy that is either de novo or acquired still occurs. Understanding the molecular pathways that contribute to BC resistance will enable to develop new treatments for improving the efficacy of endocrine therapy. Studies have shown that estrogen receptor beta (ERβ) and its agonists inhibits the different types of cancers including BC. Herein, we investigated mechanism(s) for therapeutic efficacies of ERβ agonists in breast cancer. Methods: To investigate the mechanisms of ERβ agonists (S-Equol and LY500307), in the treatment of breast cancer, we used therapy sensitive (MCF7-Aro) and letrozole resistant (MCF7-Aro-LTLT) cells and ERβ knock down cell lines, generated by CRISPR-Cas9 technology. The wild type and ERβ knock down cells with or without treatment of ERβ agonists were analyzed, for cell proliferation, protein (Western), Gene expression array analysis, RNA-seq analysis, data-independent acquisition (DIA) mass spectrometry analyses and RNA (RT-qPCR) analysis. Xenograft and patient derived BC explants (PDEX) were used to test the antiproliferative activity of ERβ agonists. Results: Our results demonstrated that treatment with ERβ agonists, S-Equol and LY500307 inhibited the growth of both endocrine therapy sensitive and resistant breast cancer cells. Gene expression array analysis of LY500307 treated breast cancer cells showed the modulation of signaling molecules involved in cell death and cell cycle pathways. RNA-seq analysis showed that treatment with S-equol modulated the ERβ target genes involved in tumor progression and resistance to hormone therapies. Mass spectrometry based DIA analysis and Reactome pathway analysis revealed that S-equol treatment modulated the key proteins involved in DNA replication and cell cycle. Both ERβ agonists S-Equol and LY500307 inhibited the cell proliferation of parental cells whereas they could not elicits the inhibitory effect on the knock out cells. By using ERα positive PDX tumors, we have demonstrated that both the ERβ agonists inhibited the proliferation of human BC tumors. Our mechanistic studies confirmed that increased FOXO3 activation by S-equol in LTLT cells can reverse letrozole resistance. Our results showed that inhibiting FOXM1 by ERβ agonists significantly reduce the proliferation of letrozole-resistant cells. These changes were not observed in ERβ knockdown cells confirming the anti-proliferative role of ERβ in breast cancer progression. Conclusions: Collectively, our results suggest that ERβ agonists may offer a new targeted therapy for endocrine therapy resistant breast tumors. (Supported by BCRP 151884/DOD grant W81XWH-16-1-0294 and P30 CA-54174 NCI-Mays cancer center grant). Citation Format: Kumaraguruparan Ramasamy, Suryavathi Viswanadhapalli, M.A. Sureshkumar, Susan Weintraub, Ratna K. Vadlamudi, Rajeshwar R. Tekmal. Estrogen receptor β agonists reverses letrozole therapy resistance of breast cancer through FOXO3 and FOXM1 mediated actions [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4365.

Autophagic Vacuole Secretion Triggered by Chidamide Participates in TRAIL Apoptosis Effect in Breast Cancer Cells.

Breast cancer is one of the most prevalent diseases threatening women's health today. Indepth research on breast cancer (BC) pathogenesis and prevention and treatment methods are gradually receiving attention. Chidamide is a novel histone deacetylase inhibitor (HDACi) that depresses the function of histone deacetylase, consequently affecting the growth of BC cells through epigenetic modification. However, preclinical and clinical studies show that chidamide is ineffective in long-term treatment. We demonstrated in previous experiments that TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis in BC cells and is significantly less non-toxic to normal cells than chidamide. Therefore, in this study, we treated BC cells with chidamide and TRAIL to explore a novel option to reduce the clinical toxicity through augmenting the sensitivity for BC cells. Results from the MTT and cell viability assays indicated that the combination of chidamide and TRAIL in MCF-7 and MDA-MB-231 cells induced BC cell death, while maintaining a reduced concentration of chidamide. Autophagy assay and annexin V analysis showed that the autophagosome microtubuleassociated protein1light chain3-II (LC3-II) was abnormally increased and much more early and late phase of apoptotic cells appeared during chidamide and TRAIL induction. Anti-tumor assays in a BC tumor xenograft model displayed that the mixture of chidamide and TRAIL exhibited stronger effects on inhibiting tumor growth. The data from real-time PCR and western blotting showed that the cytotoxic effect correlated with the expressions of related apoptosis and autophagy factors. Our data are the first to demonstrate the synergistic effects of chidamide and TRAIL in BC cells, specifically, the pharmacological effects on cell death induction. These results lay a solid experimental and theoretical basis to solve the clinical resistance of chidamide.

Combined treatment of menadione and calcitriol increases the antiproliferative effect by promoting oxidative/nitrosative stress, mitochondrial dysfunction, and autophagy in breast cancer MCF-7 cells

The aim of this study was to determine new insights into the molecular mechanisms involved in the antiproliferative action of menadione + calcitriol (MEN+D) on MCF-7 cells. After 24 h, MEN+D inhibited the cell growth but was not observed with each single treatment. The combined drugs reduced the mitochondrial respiration at that time, as judged by an increase in the proton leak and a decrease in the ATP generation and coupling efficiency. At longer times, 48 or 96 h, either D or MEN reduced the proliferation, but the effect was higher when both drugs were used together. The combined treatment increased the superoxide anion ([Formula: see text]) and nitric oxide (NO•) contents as well as acidic vesicular organelles (AVOs) formation. The percentage of cells showing the lower mitochondrial membrane potential (ΔΨm) was highly increased by the combined therapy. LC3-II protein expression was enhanced by any treatment. In conclusion, the antiproliferative action of MEN+D involves oxidative/nitrosative stress, mitochondrial alteration, and autophagy. This combined therapy could be useful to treat breast cancer cells because it inhibits multiple oncogenic pathways more effectively than each single agent.

Folic Acid Conjugated Nanocarriers for Efficient Targetability and Promising Anticancer Efficacy for Treatment of Breast Cancer: A Review of Recent Updates

Breast cancer (BC) is the commonest cause of cancer deaths among Women. It is known to be caused due to mutations in certain receptors, viz. estrogens or progesterones. The most frequently used conventional treatment strategies against BC include chemotherapy, radiation therapy, and partial or entire mastectomy, however, these strategies are often associated with multiple adverse effects, thus reducing patient compliance. Advancement of nanotechnology in the medical application has been made to enhance the therapeutic effectiveness with a significant reduction in the unintended side-effects associated with incorporated anticancer drugs against cancer. The surface engineering technology of the nanocarriers is more pronounced in delivering the therapeutics specifically to target cells. Consequently, folic acid, a small molecular ligand for the folate receptor overexpressed cells, has shown immense response in treating BC cells. Folic acid conjugated nanocarriers have shown remarkable efficiency in targeting overexpressed folate receptors on the surface of BC cells. Binding of these target-specific folate-conjugated nanocarriers substantially improves the internalization of chemotherapeutics in BC cells, without much exposing the other parts of the body. Simultaneously, these folate-- conjugated nanocarriers provide imaging for regular monitoring of targeted drug delivery systems and their responses to an anticancer therapy. Therefore, this review demonstrates the potential of folate-conjugated nanotherapeutics for the treatment and theranostic approaches against BC along with the significant challenges to anticancer therapy, and the prospective insights into the clinical importance and effectiveness of folate conjugate nanocarriers.

Effects of 8-hydroxyquinoline-coated graphene oxide on cell death and apoptosis in MCF-7 and MCF-10 breast cell lines.

Objective(s):Breast cancer is a devastating disease related to women. The anticancer properties of 8-hydroxyquinoline (8HQ) and the increasing use of graphene oxide (GO), as a drug delivery system with anti-cancerous properties, led us to investigate the toxicity and apoptosis-induction capability of 8HQ-coated GO on breast cancer cells compared with normal breast cells.Materials and Methods:Breast cancer (MCF-7) and normal breast (MCF-10) cell lines were treated with several doses of 8-HQ-coated GO for 12, 24, and 48 hr. The toxicity of the nanocomposite was measured using MTT assay and the effect of the nanocomposite on cell apoptosis was determined by examining the expression of P53, P21, Bax, and BCL2 genes, as well as Annexin-V /PI apoptosis assay.Results:There were significantly increased cell deaths in nanocomposite-treated MCF-7 breast cancer cells, compared with treated normal breast cells. Significantly increased expression of P53, P21, and Bax genes and reduced expression of BCL2 gene were found in the treated breast cancer cell line compared with the normal cell line. Annexin-V/PI assay also illustrated significant induction of apoptosis in MCF-7 following nanocomposite treatment.Conclusion:Overall, 8HQ-coated GO has toxicity for breast cancer cell lines and one of the mechanisms through which this nanocomposite can induce cell death is the induction of apoptosis. With complementary in vitro and in vivo studies, this nanocomposite can be suggested as a nano-drug with anti-cancer properties.

Oncolytic virus therapy benefits from control theory.

Oncolytic virus therapy aims to eradicate tumours using viruses which only infect and destroy targeted tumour cells. It is urgent to improve understanding and outcomes of this promising cancer treatment because oncolytic virus therapy could provide sensible solutions for many patients with cancer. Recently, mathematical modelling of oncolytic virus therapy was used to study different treatment protocols for treating breast cancer cells with genetically engineered adenoviruses. Indeed, it is currently challenging to elucidate the number, the schedule, and the dosage of viral injections to achieve tumour regression at a desired level and within a desired time frame. Here, we apply control theory to this model to advance the analysis of oncolytic virus therapy. The control analysis of the model suggests that at least three viral injections are required to control and reduce the tumour from any initial size to a therapeutic target. In addition, we present an impulsive control strategy with an integral action and a state feedback control which achieves tumour regression for different schedule of injections. When oncolytic virus therapy is evaluated in silico using this feedback control of the tumour, the controller automatically tunes the dose of viral injections to improve tumour regression and to provide some robustness to uncertainty in biological rates. Feedback control shows the potential to deliver efficient and personalized dose of viral injections to achieve tumour regression better than the ones obtained by former protocols. The control strategy has been evaluated in silico with parameters that represent five nude mice from a previous experimental work. Together, our findings suggest theoretical and practical benefits by applying control theory to oncolytic virus therapy.

Solanum nigrum Anticancer Effect Through Epigenetic Modulations in Breast Cancer Cell Lines

Background: DNA methylation plays an important role in the regulation of gene expression in mammalian cells and often occurs at CpG islands in the genome. It is more reversible than genetic variations and has therefore attracted much attention for the treatment of many diseases, especially cancer. In the present study, we investigated the effect of Solanum nigrum Extract (SNE) on the methylation status of the VIM and CXCR4 genes in breast cancer cell lines. Methods: The Trypan blue assay was used to study the effect of SNE at various concentrations of 0, 0.1, 1.5, 2.5, 3.5 and 5 mg/ml for 48 h on the survival of three human breast cancer cell lines MCF7, MDA-MB-468, MDA-MB-231. Methylation status of VIM and CXCR4 genes in breast cancer cell lines was assessed by Methylation-Specific PCR (MSP) method. Also, methylation changes of VIM and CXCR4 genes in breast cancer cell lines after treatment with 0.1 mg/ml of SNE for 6 days were analyzed by MSP method. To confirm the effect of SNE on methylation of VIM and CXCR4 genes, Real-Time PCR was performed. Results: The Trypan blue assay results indicated that treatment with SNE reduced cell viability in a dose-dependent manner in breast cancer cells. Our results showed that treatment of breast cancer cells with 0.1 mg/ml of SNE hypermethylated the VIM, CXCR4 genes and significantly reduced the expression levels of their mRNA (P<0.05). Conclusion: Our findings reveal for the first time the impact of SNE on the methylation of breast cancer cells.

Computational models applied to metabolomics data hints at the relevance of glutamine metabolism in breast cancer

BackgroundMetabolomics has a great potential in the development of new biomarkers in cancer and it has experiment recent technical advances.MethodsIn this study, metabolomics and gene expression data from 67 localized (stage I to IIIB) breast cancer tumor samples were analyzed, using (1) probabilistic graphical models to define associations using quantitative data without other a priori information; and (2) Flux Balance Analysis and flux activities to characterize differences in metabolic pathways.ResultsOn the one hand, both analyses highlighted the importance of glutamine in breast cancer. Moreover, cell experiments showed that treating breast cancer cells with drugs targeting glutamine metabolism significantly affects cell viability. On the other hand, these computational methods suggested some hypotheses and have demonstrated their utility in the analysis of metabolomics data and in associating metabolomics with patient’s clinical outcome.ConclusionsComputational analyses applied to metabolomics data suggested that glutamine metabolism is a relevant process in breast cancer. Cell experiments confirmed this hypothesis. In addition, these computational analyses allow associating metabolomics data with patient prognosis.

EMT related circular RNA expression profiles identify circSCYL2 as a novel molecule in breast tumor metastasis.

Substantial evidence indicates that circular RNAs (circRNAs) play vital roles in several diseases, especially in cancer development. However, the functions of circRNAs in breast cancer metastasis remain to be investigated. This study aimed to identify the key circRNAs involved in epithelial mesenchymal transition (EMT) of breast cancer and evaluated their molecular function and roles in pathways that may be associated with tumor metastasis. An EMT model was constructed by treating breast cancer cells MCF-7 and MDA-MB-231 with transforming growth factor-β1. High-throughput RNA sequencing was used to identify the differentially expressed circRNAs in EMT and blank groups of two cells, and reverse transcription-quantitative PCR was used to validate the expression of circSCYL2 in human breast cancer tissues and cells. The effects of circSCYL2 on breast cancer cells were explored by transfecting with plasmids and the biological roles were assessed using transwell assays. EMT groups of breast cancer cells exhibited the characteristics of mesenchymal cells. Furthermore, the present study found that 7 circRNAs were significantly upregulated in both the MCF-7 EMT and MDA-MB-231 EMT groups, while 16 circRNAs were significantly downregulated. The current study identified that circSCYL2 was downregulated in breast cancer tissues and cell lines, and that circSCYL2 overexpression inhibited cell migration and invasion. This study provides expression profiles of circRNAs in EMT groups of breast cancer cells. circSCYL2, which is downregulated in breast cancer tissues and cells, may play an important role in breast cancer EMT progression.

Skeletal loading regulates breast cancer-associated osteolysis in a loading intensity-dependent fashion

Osteocytes are mechanosensitive bone cells, but little is known about their effects on tumor cells in response to mechanical stimulation. We treated breast cancer cells with osteocyte-derived conditioned medium (CM) and fluid flow-treated conditioned medium (FFCM) with 0.25 Pa and 1 Pa shear stress. Notably, CM and FFCM at 0.25 Pa induced the mesenchymal-to-epithelial transition (MET), but FFCM at 1 Pa induced the epithelial-to-mesenchymal transition (EMT). This suggested that the effects of fluid flow on conditioned media depend on flow intensity. Fluorescence resonance energy transfer (FRET)-based evaluation of Src activity and vinculin molecular force showed that osteopontin was involved in EMT and MET switching. A mouse model of tumor-induced osteolysis was tested using dynamic tibia loadings of 1, 2, and 5 N. The low 1 N loading suppressed tumor-induced osteolysis, but this beneficial effect was lost and reversed with loads at 2 and 5 N, respectively. Changing the loading intensities in vivo also led to changes in serum TGFβ levels and the composition of tumor-associated volatile organic compounds in the urine. Collectively, this study demonstrated the critical role of intensity-dependent mechanotransduction and osteopontin in tumor-osteocyte communication, indicating that a biophysical factor can tangibly alter the behaviors of tumor cells in the bone microenvironment.

Abstract P6-04-19: Estrogen receptor β agonist S-Equol promotes letrozole sensitivity of endocrine therapy resistant breast cancer cells by upregulating FOXO3 expression

Abstract Background: Breast cancer (BC) is the most frequently diagnosed cancer and the primary leading cause of cancer deaths in women worldwide. Although the clinical outcome of BC patients has been considerably improved, resistance to endocrine and chemotherapy treatments contributes to BC relapse and mortality. Understanding the molecular pathways that contribute to BC resistance will enable to develop new treatments for improving the efficacy of endocrine therapy. Recent studies suggested that estrogen receptor beta (ERβ) and its ligand S-Equol promote suppression of BC progression. However, the mechanisms by which S-equol inhibits growth of BC cells and enhance therapy response remains unknown. Here, we examined the mechanisms by which S-equol contribute to BC growth inhibition in hormone therapy sensitive and resistant BC cells. Methods: We evaluated the therapeutic efficacy of S-equol in therapy sensitive (MCF7-Aro) and letrozole resistant (MCF7-Aro-LTLT) cells. Expression levels of target genes were evaluated in both cell lines by global RNA-seq analysis, data-independent acquisition (DIA) mass spectrometry analyses, qRT-PCR and Western blot. ERβ knock down cell lines were generated by CRISPR-Cas9 technology. Xenograft and patient derived BC explants (PDEX) were used for preclinical evaluation of the antiproliferative activity of S-equol. Results: S-equol reduced the growth of endocrine sensitive and resistant BC models in vitro and in vivo. Treatment of ER-positive PDEX with S-equol decreased the proliferation compared to untreated tumors. RNA-seq analysis of S-equol treated BC cells showed modulation of ERβ target genes involved in tumor progression and resistance to hormone therapies. Mass spectrometry based DIA analysis showed that S-equol treatment upregulated 438 proteins and downregulated 429 proteins in MCF7-Aro cells compared to controls. Whereas, DIA analysis in Letrozole-resistant cells revealed that S-equol upregulated 572 proteins and downregulated 481 proteins compared to controls. Reactome pathway analysis revealed that S-equol treatment modulated the proteins involved in DNA replication, cell cycle, proteins regulating p53 activity and VEGF-VEGFR2 pathway. Our mechanistic studies confirmed that treatment with S-equol upregulated FOXO3 and downregulated FOXM1. Using CRISPR-Cas9 mediated ERβ knockout cells, we confirmed that S-equol could not modulate forkhead box transcription factors in BC cells lacking ERβ compared to parental cells. Conclusions: Collectively, our results suggest that S-equol exhibits its antitumor activity by targeting forkhead box transcription factors and that S-equol might be an effective treatment strategy in treating / preventing breast cancer recurrence. (Supported by BCRP 151884/DOD grant W81XWH-16-1-0294). Citation Format: Kumaraguruparan Ramasamy, Shaorong Chen, Suryavathi Viswanadhapalli, Rong Li, Ratna K Vadlamudi, Rajeshwar R Tekmal. Estrogen receptor β agonist S-Equol promotes letrozole sensitivity of endocrine therapy resistant breast cancer cells by upregulating FOXO3 expression [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-04-19.

Liquid metal droplet robot

Liquid metal (LM) droplets made from gallium-based alloys exhibit excellent biomimetic locomotion and deformation capabilities under external stimulating fields and have presented potentials in a variety of applications. However, its application in robotics is presently hampered by limited maneuverability in two-dimensional (2D) space and weak cargo carrying capacity. Here, we propose a composite liquid metal droplet robot (LMDR) which appears as a LM droplet but exhibits an extraordinary actuating performance in 3D space. The LMDR is fabricated by assembling a hollow and spherical-shaped magnetic internal framework (IF) into a LM droplet, and the IF can be disassembled from the LM droplet with the application of an external magnetic field. The maneuver of the LMDR is realized using the interplay of electric and magnetic fields, and complex actuation especially jumping to avoid obstacles, climbing steep slopes, and rotating its body to the desired posture can be achieved. The hollow IF within the LMDR has a cargo carrying capacity and we demonstrate a proof-of-concept experiment to show the transportation and controlled release of a chemical indicator using the LMDR. More importantly, an in vitro targeted drug delivery and therapy trial to treat breast cancer cells (4T1) with a drug loaded LMDR is also successfully performed. The demonstrated capabilities of the LMDR present a promising potential in developing future targeted drug delivery and soft robotic systems with high controllability and multi-functionalities.

Curcumin Inhibits the Tumorigenesis of Breast Cancer by Blocking Tafazzin/Yes-Associated Protein Axis.

PurposeThis study was aimed to explore the anti-tumor effect of curcumin on breast cancer (BC) and the underlying mechanism involving Tafazzin (TAZ)/Yes-associated protein (YAP) axis.MethodsDifferent concentrations of curcumin (0, 10, 20 and 30 μM) were used to treat BC cells (MCF-7 and MDA-MB-231 cells). The viability, colony formation, apoptosis, migration, and invasion of BC cells were detected by MTT, colony formation, flow cytometry, wound-healing and transwell assay, respectively. The protein expression of TAZ and YAP (effectors of Hippo signaling pathway) was detected by Western blot. MDA-MB-231 cells were injected into mice to verify the anti-tumor effect of curcumin in vivo.ResultsCurcumin (20 and 30 μM) inhibited the proliferation, migration and invasion, and promoted the apoptosis of MCF-7 and MDA-MB-231 cells. Curcumin decreased the protein expression of TAZ and YAP in MCF-7 and MDA-MB-231 cells. Overexpression of YAP reversed the anti-tumor effect of curcumin on MDA-MB-231 cells. In addition, curcumin (100, 200 and 300 mg/kg/d) inhibited the growth of tumor xenografts in mice, and down-regulated the protein expression of TAZ and YAP in tumor xenografts. However, curcumin at a concentration of 300 mg/kg/d slowed the increasing of body weight in mice.ConclusionCurcumin inhibited the tumorigenesis of BC by blocking TAZ/YAP axis.

The expression and significance of chromobox protein homolog 2 in breast cancer

Objective: To study the relationship between the expression of Chromobox protein homolog (CBX) mRNA and the clinicopathological prognosis of breast cancer, and to investigate the possibility of Chromobox protein homolog 2 as a therapeutic target for breast cancer. Methods: First, we analyzed the mRNA expression of 8 CBX family genes by METABRIC database, and investigated the relationship between the expression of CBX2 mRNA and the clinicopathological parameters of breast cancer. Then we explored its relationship with prognosis. CBX2 siRNA was used to treat breast cancer cell lines with high expression of CBX2(SUM159 and SUM1315). The effects of knockdown of CBX20 on mRNA and protein expression and cell proliferation were observed. Results: According to the analysis of METABRIC database, among the 8 CBX genes, the most obvious increase in mRNA expression was CBX2, and 22.47% (445/1 980) of the patients showed high mRNA expression. The high expression of CBX2 was closely related to tumor histological grade and the molecular type of breast cancer (P<0.001). Compared with the low-expression group of CBX2 mRNA, the proportion of HER2 breast cancer (28.1% vs 7.5%) and Basal-like (44.5% vs 8.5%) in the high-expression group were both higher. Patients with high CBX2 expression had significantly shorter disease-free survival (DFS) and overall survival (OS). The knockdown of CBX2 by siRNA inhibited the proliferation of breast cancer cells. Conclusion: CBX2 is closely related to the prognosis of breast cancer and may be a target for breast cancer treatment.

Expression and prognosis of N-α-acetyltransferase gene 10 in breast cancer

Objective To study the possibility of protein acetyltransferase gene 10 (NAA10) as a target for breast cancer treatment. Methods Based on METABRIC database, 1974 cases of breast cancer patients were selected, including 718 cases of Luminal A subtype, 488 cases of Luminal B subtype, 240 cases of human epidermalgrowth factor receptor-2 (Her-2) subtype, 329 cases of basal-like subtype, and 199 cases of normal-like subtype. Using METABRIC database, the relationship between 33 acetyltransferase genes and the prognosis of breast cancer, and the relationship between NAA10 gene expression and clinicopathological parameters of breast cancer were studied. NAA10 small interfering RNA (siRNA) was used to treat breast cancer cell lines with NAA10 high expression, and the effect of NAA10 gene silencing on breast cancer cell proliferation was detected by cell counting kit-8 (CCK-8) and plate clone formation assays. Results The mRNA expression of NAA10 was significantly correlated with the disease-free survival rate (DFS) and overall survival rate of breast cancer (P<0.05), and the relative risk ratios were 1.31 (1.14-1.51) and 1.13 (1.01-1.25), respectively. NAA10 gene expression was positively correlated with breast cancer histological grade, lymph node status, and Nottingham index (NPI) (P<0.01). NAA10 mRNA and protein levels were highest in Basal-like breast cancer. Compared with control group, NAA10 gene silencing inhibited 50% breast cancer cell proliferation (P<0.05). Conclusion NAA10 gene is closely related to breast cancer cell proliferation and its expression level is closely related to breast cancer prognosis. NAA10 gene may become a target for future treatment of breast cancer. Key words: N-α-acetyltransferase gene 10; Lysine acetyltransferase; Small interfering RNA; Breast cancer

Promoter hypermethylation of the CFTR gene as a novel diagnostic and prognostic marker of breast cancer.

Breast cancer is the most commonly diagnosed cancer and the leading cause of cancer-related deaths among women. New biomarkers with definite diagnostic and prognostic efficacy are urgently needed. Here, we showed that the promoter of the cystic fibrosis transmembrane conductance regulator (CFTR) was hypermethylated in breast cancer. The messenger RNA level of CFTR was downregulated in breast cancer. Notably, all 19 breast cancer patients with hypermethylated CFTR were diagnosed with invasive carcinoma. Moreover, CFTR was upregulated in decitabine (10 μM) treated breast cancer cells. Overexpression of CFTR inhibited cell growth whereas knockdown of CFTR promoted cell invasion. In the tissue array analysis, the CFTR protein level decreased significantly in breast cancer and low CFTR protein level correlated with poor survival with a P-value of 0.034. Thus, promoter hypermethylation of the CFTR gene might be a novel diagnostic marker of breast cancer.

Doxorubicin loaded on chitosan-protamine nanoparticles triggers apoptosis via downregulating Bcl-2 in breast cancer cells

Cancer-specific drug delivery is a reliable approach to evade undesirable side effects and increase the bioavailability of the drug in tumor cells. In the present study, we treated breast cancer cells MDA-MB-231 with doxorubicin (DOX) loaded on chitosan-protamine nanoparticles (CPNPs) to investigate the composite ability to induce apoptosis. CPNPs were prepared and characterized using FTIR spectroscopy, transmission electron microscope, and zeta potential determination. CPNPs showed a drug encapsulation efficiency (EE) of 21%, drug loading capacity (LC) of 3.65% and a particle size of 117 nm. In vitro release study indicated that DOX release from CPNPs-DOX was pH-dependent, where it released with rates 60.10%, 44.15% and 25.10% at pH 4.0, 6.8 and 7.4, respectively. Cells were treated with three concentrations (1, 2, and 3 μM) of either free DOX, doxorubicin loaded on CPNPs (CPNPs-DOX), or empty carrier for 48 h. Cell viability was assessed using MTT and trypan blue assays. Meanwhile, apoptosis rate using PI/Annexin V-FITC staining cell cycle analysis were performed using PI staining-based flow cytometry. MTT and trypan blue assays showed a significant decrease in the viability/count upon treating cells with DOX-CPNPs. Flow cytometry data revealed an arrest of the breast cancer cell at G2/M (47.18%) in the CPNPs-DOX treatment. Quantitative real time PCR analysis showed that CPNPs-DOX treatment has significantly downregulated Bcl-2 compared with free DOX treatment and control. These results indicate the efficiency of using CPNPs as a drug carrier for DOX in treating breast cancer cells, however, these conclusion needs further investigation.

Hsa_circ_0008945 promoted breast cancer progression by targeting miR-338-3p.

PurposeTo detect the expression and function of circ_0008945 in breast cancer (BC) and to explore its potential molecular mechanisms in BC tumorigenesis.Materials and methodsWe measured expression levels of circ_0008945, miR-338-3p and homeobox A3 (HOXA3) in BC tissue specimens and cells using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). We examined the effects of all three genes on BC cell proliferation using Cell Counting Kit-8 (CCK-8) and colony formation assays. We also performed a Transwell assay to assess the migratory and invasive ability of treated BC cells. BC cell apoptosis was assessed using flow cytometric (FCM) analysis; interaction between miR-338-3p and circ_0008945 or HOXA3 was verified by dual-luciferase reporter assay as well as by ribonucleic-acid (RNA) pulldown. Finally, we used an in vivo tumor growth assay to assess the role of circ_0008945 overexpression in BC tumor growth.ResultsWe found that circ_0008945 expression was significantly increased in both BC tissue specimens and cells. This increase was correlated with poor prognosis in BC patients. Knockdown of circ_0008945 inhibited BC cell proliferation, migration and invasion while promoting BC cell apoptosis in vitro. Overexpression of circ_0008945 remarkably promoted BC tumor growth in vivo. Mechanistically, circ_0008945 acted as a miRNA sponge for miR-338-3p and inhibited its expression in BC cells. Moreover, miR-338-3p targeted and inhibited HOXA3.ConclusionWe found that circ_0008945 acted as a BC oncogene by physically binding miR-338-3p, which further targeted and regulated HOXA3.

Cisplatin-functionalized three-dimensional magnetic SBA-16 for treating breast cancer cells (MCF-7)

The engineering of multifunctional therapeutics in an integrated single platform is demonstrated using three-dimensional SBA-16 (S-16). 10 wt% iron oxide nanoparticles (Fe) were loaded into the cage type of cubic pores through enforced adsorption technique. Fe/S-16 is then functionalized with amine-based silane (A), polyacrylic acid (P) and cisplatin (Cp). The physicochemical textural analysis showed the formation of nano metal oxide distributions at pore walls of S-16 with magnetization of 2.39 emu/g. S-16 based nanoformulations showed high percentage of Cp adsorption (90%) and percentage cumulative release (60%). in vitro study of Fe/S-16-A-Cp showed high toxicity against breast cancer cell line MCF-7 and normal cell line Human foreskin fibroblast (HFF-1) compared to Fe/S-16 indicating cisplatin profusion inside the cells than free cisplatin. While skin fibroblast seems to be resistant to Fe/S-16-AP-Cp with very high LC50 in compare to MCF-7. This indicates the unrelease of cisplatin in skin fibroblast after Fe/S-16-AP-Cp treatment due to effective encapsulation inside the cubic pores and core blockage due to pH-sensitive polyacrylic acid. Also, these treatments resulted in morphological changes in the cells such as DNA condensation and nuclear fragmentation.