Stellera chamaejasme extract against multidrug resistance of breast cancer cell line MCF-7 / 中国中药杂志

This study explored the effect and underlying mechanism of Stellera chamaejasme extract(SCE) on multidrug resistance of breast cancer. The chemotherapy-sensitive breast cancer cell line MCF-7 and adriamycin(ADR)-resistant cell line MCF-7/ADR were used as experimental subjects. MTT assay was used to detect cell proliferation activity. Pi staining was used to detect the cell cycle. 4',6-Diamidino-2-phenylindole, dihydrochloride(DAPI) staining and flow cytometry were used to detect apoptosis. Dansylcadaverine(MDC) staining and GFP-LC3B-Mcherry adenovirus transfection were used to detect autophagy. The protein expression of Bcl-2, Bax, caspase-9, caspase-3, LC3B, p62, and Beclin-1 was detected by Western blot. The results showed that SCE could significantly inhibit the proliferation of both sensitive and resistant breast cancer cell lines. The drug resistance factor was 0.53, which was significantly lower than 59 of ADR. Meanwhile, the proportion of sensitive/resistant cells in the G_0/G_1 phase increased significantly after SCE treatment. In addition, DAPI staining showed that a series of apoptosis phenomena such as nuclear pyknosis, staining deepening, and nuclear fragmentation appeared in sensitive/resistant cell lines after SCE administration. Moreover, the results of flow cytometry double staining showed that the proportion of apoptotic cells in sensitive/resistant cell lines increased significantly after SCE administration. Besides, Western blot showed that the protein expression levels of caspase-3, caspase-9, and Bcl-2 significantly decreased and the expression level of Bax protein significantly increased in both breast cancer cell lines after SCE administration. Furthermore, SCE could also increase the positive fluorescent spots after MDC staining and yellow fluorescent spots after GFP-LC3B-mcherry transfection, and up-regulate the expression levels of autophagy-related proteins LC3B-Ⅱ, p62, and Beclin-1 in breast cancer cells. In summary, SCE may play the role of anti-multidrug resistance by blocking the cell cycle of breast cancer multidrug-resistant cells, blocking autophagy flow, and ultimately interfering with the apoptosis resistance of drug-resistant cells.

Echinacoside hampers malignant progression of breast cancer MCF-7 cells by modulating AKR1B10/ERK signal transduction / 中国中药杂志

This study analyzes the impact of echinacoside(ECH) in the proliferation, metastasis and adriamycin(ADR) resistance of breast cancer(BC) MCF-7 cells via the modulation of aldo-keto reductase family 1 member 10(AKR1B10)/extracellular signal-regulated kinase(ERK) pathway. The chemical structure of ECH was firstly confirmed. MCF-7 cells were treated with different concentration(0, 10, 20, 40 μg·mL~(-1)) of ECH for 48 h. Western blot was used to analyze expression of AKR1B10/ERK pathway-associated proteins and cell counting kit-8(CCK-8) assay to determine cell viability. MCF-7 cells were collected and classified into control group, ECH group, ECH + Ov-NC group, and ECH + Ov-AKR1B10 group. Then Western blot was employed to analyze the expression of AKR1B10/ERK pathway-associated proteins. CCK-8 and 5-ethynyl-2'-deoxyuridine(EdU) assay were used to examine cell proliferation. Cell migration was appraised with scratch assay, Transwell assay, and Western blot. Eventually, MCF-7 cells were treated with ADR for 48 h to induce ADR resistance. Cell viability was tested by CCK-8 assay and cell apoptosis was estimated based on terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL) assay and Western blot. Based on Protein Data Bank(PDB) and molecular docking, the binding affinity of ECH to AKR1B10 was assessed. Various doses of ECH decreased the expression of AKR1B10/ERK pathway-associated proteins in a dose-dependent manner and declined cell viability compared with the control group. Compared with the control group, 40 μg·mL~(-1) ECH blocked the AKR1B10/ERK pathway in MCF-7 cells and inhibited the proliferation, metastasis and ADR resistance of the cells. Compared with the ECH + Ov-NC group, ECH + Ov-AKR1B10 group showed the recovery of some biological behaviors of MCF-7 cells. ECH also targeted AKR1B10. ECH can inhibit the proliferation, metastasis, and ADR resistance of BC cells by blocking AKR1B10/ERK pathway.

Cytotoxic and Apoptotic Properties of the Flavonoid-rich Ethyl Acetate Fraction of the Crude Methanol Leaf Extract of Syzygium samarangense (Blume) Merr. (Myrtaceae) against MCF-7 Breast Cancer Cells

Introduction@#Breast cancer is the most common cancer among women in the Philippines and about 3 in every 100 Filipina will be diagnosed with breast cancer in their lifetime. There is a need to discover safe, yet inexpensive herbal extracts with potential cytotoxic properties as potential treatment modalities to treat breast cancer. @*Objectives@#This study seeks to explore the cytotoxic and apoptotic properties of the ethyl acetate fraction of the defatted crude methanol leaf extract of Syzygium samarangense in MCF-7 breast cancer cell lines. @*Methods@#Screening for flavonoids of the extracts was performed using TLC, total flavonoids, total phenols, FTIR and LC-MS spectroscopy. The hydrogen peroxide and ferric reducing anti-oxidant power were used as substrates to assess in vitro anti-oxidative properties of the extracts. The MTT dye viability assay was used to assess the cytotoxic properties of the extracts against MCF-7 cells. Apoptotic properties of the extracts in MCF-7 cells were determined by caspase-3 activation assay, DNA fragmentation patterns and fluorescence microscopy after annexin-V and propidium iodide staining. @*Results@#The abundance of flavonoids in the ethyl acetate fraction of the crude methanol leaf extract was established by TLC, FTIR, LC-MS/MS, total flavonoid and total phenol analyses. The in vitro anti-oxidative properties of this extract was comparable to ascorbic acid. The median inhibitory concentration (IC50) of this extract in MCF-7 breast cancer cell lines was 7.2 mcg/mL while doxorubicin registered an IC50 of 1.2 mcg/mL. At this concentration, the extract was not cytotoxic to normally-dividing breast epithelial cells. Cytotoxicity of the extract was mediated via apoptosis as demonstrated by DNA fragmentation, caspase-3 activation and fluorescence microscopic analyses. @*Conclusion@#The study shows that the flavonoid-rich ethyl acetate fraction of the crude methanol leaf extract of S. samarangense possesses potent apoptotic and cytotoxic properties against MCF-7 breast cancer cell lines at low concentrations.

Phytochemical and biological attributes of Bauhinia variegata L. (Caesalpiniaceae) / Atributos fitoquímicos e biológicos de Bauhinia variegata L. (Caesalpiniaceae)

Bauhinia variegata plant is a very popular and traditionally potent ethnomedicine. Therefore, it is need of hour to study ameliorative characteristics of B. variegata for novel secondary metabolites. The current study was designed to explore antiproliferative potential of B. variegata due to scant reports on this aspect. Extracts of various parts (flowers, leaves, bark, stem, and roots) were prepared by successive maceration using organic solvents in increasing order of polarity (n-hexane, ethyl acetate, methanol, and water). The determination of polyphenolic contents was done by using colorimetric methods while antioxidant potential was measured using reducing power assay. Brine shrimp lethality assay was performed for determining preliminary cytotoxicity and antiproliferative activity against breast cancer MCF-7 cell line using MTT protocols. Moreover, antimicrobial activities were detected by using disc diffusion assay. The alpha-amylase assay was performed to monitor the antidiabetic potential of the plant. In case of phytochemical analysis methanolic extract of leaves and bark showed highest phenolic and flavonoids contents. n-Hexane and ethyl acetate extracts of stem and roots exhibited more than 90% mortality with LD50 ranges between 1-25 µg/mL when studied by brine shrimp lethality assay. n-Hexane and ethyl acetate extracts of roots and stem also showed antiproliferative activity against human breast cancer MCF-7 cell line with IC50 values ranges between 12.10-14.20 µg/mL. Most of the extracts displayed moderately high antibacterial and antifungal activities. The n-hexane extract of roots showed antidiabetic activity with 60.80 ± 0.20% inhibition of alpha-amylase. In sum, these preliminary results will be useful for further compound isolation from selected plant parts for the discovery of antibacterial, antidiabetic, and anticancer lead candidates.

A planta Bauhinia variegata é uma etnomedicina muito popular e tradicionalmente potente. Portanto, as características de melhoria de B. variegata foram estudadas. Foi avaliada a determinação dos teores antioxidantes e polifenólicos. O ensaio de letalidade do camarão de salmoura foi realizado para determinar a citotoxicidade preliminar e a atividade antiproliferativa contra linhas de células de câncer de mama MCF-7 usando protocolos de MTT. Além disso, foram detectadas atividades antimicrobianas. O ensaio da alfa-amilase foi realizado para monitorar o potencial antidiabético da planta. Dentre vinte amostras diferentes, o extrato metanólico (EM) da casca apresentou os maiores teores fenólicos totais. A EM das folhas apresentou excelente conteúdo de flavonoides, atividade antioxidante significativa foi exibida pelo extrato hexânico do caule. O extrato do caule de hexano exibe 77,40% como citotóxico em DL50 10,50 µg/mL quando avaliado através do ensaio de letalidade de artêmia. Extratos de hexano e acetato de etila de raiz e caule mostraram atividade antiproliferativa contra a linhagem celular MCF7 de câncer de mama humano (IC50 12,10-14,20 µg/mL). Para potencial antimicrobiano importante, vários extratos exibiram excelentes atividades antibacteriana e antifúngica, enquanto o extrato de n-hexano da raiz mostrou atividade antidiabética (60,80 ± 0,20% na concentração de 200 µg/mL). Em suma, estes resultados preliminares serão úteis para isolamento adicional de compostos a partir de partes de plantas selecionadas para a descoberta de candidatos a antibacterianos, antidiabéticos e anticâncer.

In vitro cytotoxicity assay of Fucoidan extracted from Turbinaria conoides against cancer cell lines MCF7, A549, and normal cell line L929

Abstract The main aim of the study is to quantify the cytotoxic property of the Fucoidan extracted from the Turbinaria conoides using the MTT assay with the standard fucose. Fucoidan was extracted using the soaked water method and it was determined using the HPLC procedure the obtained Test sample Fucoidan extracted from the Turbinaria conoides and standard fucose was subjected to the cytotoxicity assay against the MCF7 Human breast cancer cell line, A549 lung cancer cell line, and L929 normal mouse fibroblast cell line. From the results it was found that the Test sample showed good IC50 value for MCF7 cell line then A549 with an increasing concentration 24 hours incubation at 37°C The IC50 for MCF7 was 115.21 µg/ml and A549 396.46µg/ml and the Fucoidan extract was checked for its cytotoxicity against the normal mouse fibroblast cell line L929, Fucoidan was found non-lethal to the L929 mouse fibroblast normal cell line. Standard fucose also gave a significant result towards MCF7 and against the L929. This indicates that the Fucoidan extracted from Tubinaria conoides shows better anticancer potential in it. Hence its application can be further extended in the pharmacological fields.

Isobavachalcone induces cell death through multiple pathways in human breast cancer MCF-7 cells / 南方医科大学学报

OBJECTIVE@#To explore the effects of isobavachalcone (IBC) on cell death of human breast cancer MCF-7 cells and explore the possible mechanism.@*METHODS@#MCF-7 cells were treated with different concentrations of IBC, and the changes in cell proliferation were assessed using MTT assay. Apoptosis of MCF-7 cells following treatment with 10, 20, and 40 μmol/L IBC was analyzed using flow cytometry with annexin V-FITC/PI double staining and fluorescence microscopy, and the expressions of apoptosis- and autophagy-related proteins (Bax, Bcl-2, Akt, p-Akt, p62, and LC3) were detected with Western blotting. Electron microscopy was used to observe the changes in submicrostructure of the cells following treatment with 40 μmol/L IBC. JC-1 assay kit, ATP assay kit, and reactive oxygen species (ROS) kit were used to determine the effect of IBC on mitochondrial function of the cells.@*RESULTS@#MTT assay showed that IBC significantly inhibited the proliferation of MCF-7 cells in a concentration- and time-dependent manner, with IC50 values of 38.46, 31.31, and 28.26 μmol/L at 24, 48, and 72 h, respectively. IBC also concentration-dependently induced apoptosis of MCF-7 cells. IBC-induced cell death was inhibited by z-VAD-fmk, a caspase inhibitor (P < 0.05), but not by the necroptosis inhibitor necrostatin-1 (Nec-1). Western blotting showed that IBC-induced MCF-7 cell apoptosis by increasing Bax expression and down-regulating the expressions of Bcl-2, Akt and p-Akt-473 (all P < 0.05). With the increase of IBC concentration, the expression of autophagy-related protein p62 and the LC3-II/I ratio increased progressively. Electron microscopy revealed the presence of autophagic bodies in IBC-treated MCF-7 cells. IBC treatment also resulted in decreased mitochondrial membrane potential and intracellular ATP level and increased ROS accumulation in MCF-7 cells (P < 0.05).@*CONCLUSION@#IBC is capable of inducing both apoptosis and autophagy in MCF-7 cells, suggesting the potential value of IBC as a lead compound in the development of anti-breast cancer agents.

Overexpression of NAT10 induced platinum drugs resistance in breast cancer cell / 中华肿瘤杂志

Objective: To observe the platinum drugs resistance effect of N-acetyltransferase 10 (NAT10) overexpression in breast cancer cell line and elucidate the underlining mechanisms. Methods: The experiment was divided into wild-type (MCF-7 wild-type cells without any treatment) group, NAT10 overexpression group (H-NAT10 plasmid transfected into MCF-7 cells) and NAT10 knockdown group (SH-NAT10 plasmid transfected into MCF-7 cells). The invasion was detected by Transwell array, the interaction between NAT10 and PARP1 was detected by co-immunoprecipitation. The impact of NAT10 overexpression or knockdown on the acetylation level of PARP1 and its half-life was also determined. Immunostaining and IP array were used to detect the recruitment of DNA damage repair protein by acetylated PARP1. Flow cytometry was used to detect the cell apoptosis. Results: Transwell invasion assay showed that the number of cell invasion was 483.00±46.90 in the NAT10 overexpression group, 469.00±40.50 in the NAT10 knockdown group, and 445.00±35.50 in the MCF-7 wild-type cells, and the differences were not statistically significant (P>0.05). In the presence of 10 μmol/L oxaliplatin, the number of cell invasion was 502.00±45.60 in the NAT10 overexpression group and 105.00±20.50 in the NAT10 knockdown group, both statistically significant (P<0.05) compared with 219.00±31.50 in wild-type cells. In the presence of 10 μmol/L oxaliplatin, NAT10 overexpression enhanced the binding of PARP1 to NAT10 compared with wild-type cells, whereas the use of the NAT10 inhibitor Remodelin inhibited the mutual binding of the two. Overexpression of NAT10 induced PARP1 acetylation followed by increased PARP1 binding to XRCC1, and knockdown of NAT10 expression reduced PARP1 binding to XRCC1. Overexpression of NAT10 enhanced PARP1 binding to LIG3, while knockdown of NAT10 expression decreased PARP1 binding to LIG3. In 10 μmol/L oxaliplatin-treated cells, the γH2AX expression level was 0.38±0.02 in NAT10 overexpressing cells and 1.36±0.15 in NAT10 knockdown cells, both statistically significant (P<0.05) compared with 1.00±0.00 in wild-type cells. In 10 μmol/L oxaliplatin treated cells, the apoptosis rate was (6.54±0.68)% in the NAT10 overexpression group and (12.98±2.54)% in the NAT10 knockdown group, both of which were statistically significant (P<0.05) compared with (9.67±0.37)% in wild-type cells. Conclusion: NAT10 overexpression enhances the binding of NAT10 to PARP1 and promotes the acetylation of PARP1, which in turn prolongs the half-life of PARP1, thus enhancing PARP1 recruitment of DNA damage repair related proteins to the damage sites, promoting DNA damage repair and ultimately the survival of breast cancer cells.

Role of heat-shock proteins in infection of human adenocarcinoma cell line MCF-7 by tumor-adapted rotavirus isolates / Papel de las proteínas de choque térmico en la infección de la línea celular de adenocarcinoma humano MCF-7 por aislados de rotavirus adaptados a tumores

Abstract Background: Viruses are being used as alternative and complementary tools for treating cancers. Oncolytic viruses exhibit tumor tropism, ability to enhance anti-tumor immunity and ability to be used in combination with conventional chemotherapy and radiotherapy. We have recently selected some rotavirus isolates which are adapted to efficiently infect and kill tumor cell lines. Aim: We tested five tumor cell-adapted rotavirus isolates for their ability to infect the human adenocarcinoma cell line MCF-7. Methods: Cell surface membrane-associated proteins mediating virus particle attachment were characterized using ELISA, immunoprecipitation, FACS analysis, and antibody blocking. Results: It was found that heat shock proteins (HSPs) such as Hsp90, Hsp70, Hsp60, and Hsp40 are expressed on the cell surface forming complexes with protein disulfide isomerase (PDI), integrin β3, and heat shock cognate protein 70 (Hsc70) in lipid raft microdomains. Interaction of rotavirus isolates with these cellular proteins was further confirmed by a competition assay and an inhibition assay involving the HSPs tested. Conclusion: Our findings suggest that the tumor cell-adapted rotavirus isolates studied here offer a promising tool for killing tumor cells, thus encouraging further research into this topic, including animal models.

Resumen Antecedentes: Los virus se utilizan como herramientas alternativas y complementarias para el tratamiento del cáncer. Los virus oncolíticos exhiben tropismo por tumores, capacidad para intensificar la inmunidad antitumoral y la capacidad para utilizarse en combinación con quimioterapia y radioterapia convencionales. Recientemente, hemos seleccionado algunos aislamientos de rotavirus que están adaptados para infectar y eliminar de manera eficiente líneas de células tumorales. Objetivo: Se ensayaron cinco aislamientos de rotavirus adaptados a células tumorales para determinar su capacidad para infectar la línea celular de adenocarcinoma humano MCF-7. Métodos: Las proteínas asociadas a la membrana de la superficie celular que median la unión de partículas de virus se caracterizaron mediante ELISA, inmunoprecipitación, análisis FACS y bloqueo de anticuerpos. Resultados: Se encontró que las proteínas de choque térmico (HSPs) como Hsp90, Hsp70, Hsp60 y Hsp40 se expresan en la superficie celular formando complejos con la proteína disulfuro isomerasa (PDI), la integrina β3 y la proteína análoga de choque térmico 70 (Hsc70) en microdominios lipídicos (rafts). La interacción de los aislamientos de rotavirus con estas proteínas celulares se confirmó adicionalmente mediante un ensayo de competición y un ensayo de inhibición que incluía las HSP ensayadas. Conclusión: Nuestros hallazgos sugieren que los aislamientos de rotavirus adaptados a las células tumorales estudiados aquí ofrecen una herramienta prometedora para eliminar las células tumorales, lo que estimula más investigaciones sobre este tema, incluidos los modelos animales.

Low-Temperature Extracts of Purple Blossoms of Basil (Ocimum Basilicum L) Intervened Mitochondrial Translocation Contributes Prompted Apoptosis in Human Breast Cancer Cells

BACKGROUND: The preventive and therapeutic medical utilization of this plant is an age-long practice across the globe. This study aimed to validate the impact of dark purple blossoms of basil (Ocimum basilicum L.) aqueous extract at low temperature (0 °C) mediated mitochondrial fission contributed to induced apoptosis in human breast cancer cells. METHODS: Fresh blossoms were extracted at low temperature (0 °C) using a watery solvent. Human MCF7 breast cancer cells were then treated with 3 separate fluctuated concentrations of 0, 50, 150 and 250 µg/mL for 24 and 48 h. RESULTS: The outcomes demonstrated the presence of anthocyanins, anthraquinones, tannins, reducing sugars, glycosides, proteins, amino acids, flavonoids and volatile oils and nonappearance of Terpinoids and alkaloids. Contrastingly, frail presence of steroids in basil blossoms aqueous concentrate was noted. In addition, the results from a phytochemical subjective examination of basil (Ocimum basilicum L.) blossoms aqueous extract demonstrated that most of the credited natural impacts containing more remarkable contents of antioxidants and anticancer compounds in basil blossoms aqueous extract. Moreover, the restraint of glucose take-up was alleviated mediated by a dose-dependent manner in MCF7 cells with basil (Ocimum basilicum L.) blossoms aqueous extract inducted for 24 h, resulting in mitochondrial fission. CONCLUSION: This is the first study that shows the impact of the aqueous extract of basil (Ocimum basilicum L.) blossoms was extracted at low temperature (0°C/6 h) underlined high amounts of flavonoids and phenolic compounds bearing more anticancer and antioxidant activities compared to another aqueous extract (using boiled water solvent) and alcoholic extracts.

The role of vulpinic acid as a natural compound in the regulation of breast cancer-associated miRNAs

BACKGROUND: Breast cancer is the most frequently diagnosed cancer, and no effective treatment solution has yet been found. The number of studies based on the research of novel natural compounds in the treatment of breast cancer has been increasing in recent years. The anticancer properties of natural compounds are related to the regulation of microRNA (miRNA) expression. Therefore, changing the profile of miRNAs with the use of natural products is very important in cancer treatment. However, the role of vulpinic acid and related miRNAs in breast cancer progression remains unknown. Vulpinic acid, methyl (as2E)-2-(3-hydroxy-5-oxo-4-phenylfuran-2-ylidene)-2 phenylacetate, is a natural product extracted from the lichen species and shows an anticancer effect on different cancer cells. METHODS: This study examines the effects of vulpinic acid on the miRNA levels of breast cancer (MCF-7) cells and its relationship with cell proliferation and apoptosis levels. The antiproliferative effect of vulpinic acid was screened against MCF-7 breast cancer cells and MCF-12A breast epithelial cells using the xCELLigence real-time cell analysis system. We analyzed the altered miRNA expression profile in MCF-7 breast cancer cells versus MCF-12A cells following their response to vulpinic acid through microarray analysis. The microarray analysis results were confirmed through quantitative real-time PCR and bioinformatics analysis. RESULTS: The results of the miRNA array and bioinformatic analyses demonstrated that 12 miRNAs were specifically responsive to vulpinic acid in MCF-7 breast cancer cells. This is the first study to reveal that vulpinic acid inhibits the expression of 12 miRNAs and suppresses breast cancer cell proliferation. The study also revealed that vulpinic acid may downregulate the expression of 12 miRNAs by repressing the FOXO-3 gene. The miRNA targets were mainly found to play a role in the apoptosis, cell cycle and MAPK pathways. Moreover, Bcl-2, Bax, procaspase-3 and procas-pase-9 protein levels were assessed by western blot analysis for validation of apoptosis at the protein level. CONCLUSION: This study revealed the molecular mechanisms of vulpinic acid on breast cancer and showed that vulpinic acid regulates apoptosis signaling pathways by decreasing the expression of miRNAs. The miRNA expression patterns illuminate the underlying effect of vulpinic acid in breast cancer treatment.

Regorafenib Suppresses Migration of and Induces Cell Cycle Arrest and Apoptosis in MCF-7 Cells

This study investigated the mechanism underlying the suppression of estrogen receptor-positive MCF-7 cell growth by regorafenib. MCF-7 cells were treated with regorafenib, and the effect of regorafenib on multiple cancer-associated pathways was evaluated. Although regorafenib effectively inhibited the proliferation of MCF-7 cells, it had no effect on the proliferation of the normal breast epithelial cell line MCF10A. Regorafenib suppressed MCF-7 cell migration, probably by regulating the homeostatic expression of matrix metalloproteinases and the tissue inhibitor of MMPs. Furthermore, it upregulated p21 expression, downregulated cyclin B1 and cyclin D1 expresssions, and caused cell cycle arrest. In addition, regorafenib induced apoptosis in MCF-7 cells by reducing Mcl-1 expression and activating caspase signaling. These results demonstrate that regorafenib has the potential to be an effective drug for treating breast cancer

A nanoemulsion-based delivery system for imatinib and in vitro anticancer efficacy

A self-nanoemulsifying drug delivery system (SNEDDS) composed of ethyl oleate, Tween 80 and polyethylene glycol 600 was prepared as a new route to improve the efficacy of imatinib. The drug-loaded SNEDDS formed nanodroplets of ethyl oleate stabilized by Tween 80 and polyethylene glycol 600 with a diameter of 81.0±9.5 nm. The nanoemulsion-based delivery system was stable for at least two months, with entrapment efficiency and loading capacity of 16.4±0.1 and 48.3±0.2%, respectively. Imatinib-loaded SNEDDS was evaluated for the drug release profiles, and its effectiveness against MCF-7 cell line was investigated. IC50 values for the imatinib-loaded SNEDDS and an imatinib aqueous solution were 3.1 and 6.5 µg mL-1, respectively.

Effects of ICI 182, 780, an ERα and ERß antagonist, and G-1, a GPER agonist, on autophagy in breast cancer cells / Efeitos do antagonista seletivo do REα e do REß ICI 182, 780 e do agonista de GPER G-1 no processo de autofagia em células de câncer de mama

ABSTRACT Objective To investigate if ICI 182,780 (fulvestrant), a selective estrogen receptor alpha/beta (ERα/ERβ) antagonist, and G-1, a selective G-protein-coupled receptor (GPER) agonist, can potentially induce autophagy in breast cancer cell lines MCF-7 and SKBr3, and how G-1 affects cell viability. Methods Cell viability in MCF-7 and SKBr3 cells was assessed by the MTT assay. To investigate the autophagy flux, MCF-7 cells were transfected with GFP-LC3, a marker of autophagosomes, and analyzed by real-time fluorescence microscopy. MCF-7 and SKBr3 cells were incubated with acridine orange for staining of acidic vesicular organelles and analyzed by flow cytometry as an indicator of autophagy. Results Regarding cell viability in MCF-7 cells, ICI 182,780 and rapamycin, after 48 hours, led to decreased cell proliferation whereas G-1 did not change viability over the same period. The data showed that neither ICI 182,780 nor G-1 led to increased GFP-LC3 puncta in MCF-7 cells over the 4-hour observation period. The cytometry assay showed that ICI 182,780 led to a higher number of acidic vesicular organelles in MCF-7 cells. G-1, in turn, did not have this effect in any of the cell lines. In contrast, ICI 182,780 and G-1 did not decrease cell viability of SKBr3 cells or induce formation of acidic vesicular organelles, which corresponds to the final step of the autophagy process in this cell line. Conclusion The effect of ICI 182,780 on increasing acidic vesicular organelles in estrogen receptor-positive breast cancer cells appears to be associated with its inhibitory effect on estrogen receptors, and GPER does notseem to be involved. Understanding these mechanisms may guide further investigations of these receptors' involvement in cellular processes of breast cancer resistance.

RESUMO Objetivo Avaliar o efeito dos compostos ICI 182,780 (fulvestranto), um antagonista seletivo dos receptores de estrógeno alfa/beta (REα/REβ), e do G-1, um agonista seletivo de receptores de estrógeno acoplados a proteínas-G (GPER), na possível indução de autofagia em linhagens de câncer de mama MCF-7 e SKBr3, bem como o efeito de G-1 na viabilidade celular. Métodos A viabilidade celular de células MCF-7 e SKBr3 foi avaliada pelo ensaio com MTT. Para investigar a indução da autofagia, células MCF-7 foram transfectadas com GFP-LC3, um marcador de autofagossomos, e analisadas por microscopia de fluorescência em tempo real. As células MCF-7 e SKBr3 foram incubadas com o indicador de compartimentos ácidos laranja de acridina e analisadas por citometria de fluxo como indicativo para autofagia. Resultados Em células MCF-7, o ICI 182,780 e rapamicina após 48 horas levaram à diminuição da viabilidade celular, enquanto o G-1 não alterou a viabilidade no mesmo período de tratamento. Nem o ICI 182,780 e nem o G-1 induziram aumento na pontuação de GFP-LC3 em células MCF-7 até 4 horas. Já os ensaios de citometria de fluxo demonstraram que ICI 182,780 levou ao aumento de compartimentos ácidos em células MCF-7. O G-1 não aumentou estes parâmetros em ambas as linhagens. Por outro lado, ICI 182,780 e G-1 não induziram à redução da viabilidade em células SKBr3 e nem à formação de compartimentos ácidos, como etapa final do processo autofágico. Conclusão O aumento de compartimentos ácidos pelo ICI 182,780 em células de câncer de mama positivas para receptores de estrógeno parece estar associado com seu efeito inibidor de receptores de estrógeno, mas sem o envolvimento de GPER. A compreensão desses mecanismos pode direcionar estudos sobre o envolvimento dos receptores nos processos celulares de resistência do câncer de mama.

Homoeopathic Viscum album (10-3) is More Cytotoxic to in vitro Culture of Human Breast Cancer Cell Line than to Human Mesenchymal Stem Cells

BackgroundBreast cancer has been considered a public health problem and homeopathic treatments are becoming increasingly recommended due to its ways of action and absence of adverse effects. MCF-7 is an adenocarcinoma of human breast cell line useful as preclinicalmodel to screen therapeutic agents such as ultra-diluted Viscum album, an European plant which extract is commonly used in cancer therapy. AIMS MCF-7 and mesenchymal stem cells (MSC) were used to evaluate the in vitrocytotoxicity of homoeopathic Viscum album 1x10-3(VA3X). Methodscells were cultured for 24 hours in controlled environment (37.5oC and 5% CO2) in 96-well plates. After this time, VA3X was added to the culture medium in concentrations varying from 10 to 100 L/mL.A control group was maintained with culture medium only. Cells were cultivated for 48 hours in these conditions for evaluation of cell viability by MTT assay. ResultsHigher cytotoxicity was observed in MCF-7 when compared to MSC, as the lower concentration of VA3X was capable of inducing tumor cell death and not healthy cell death. The MTT assay results were that 42 L/mL of VA3X reduced MCF-7 cells viability to 50% and 62 L/mL reduced MSC cells to the same percentage, what means that tumor cells are more sensible to VA3X than heathy cells. ConclusionViscum albumpresented higher cytotoxic action on human breast cancer cell line culture than on mesenchymal stem cells. This medicine is extensively used against cancer, and the use of the homoeopathic form of it brings new possibilities as no or fewer adverse effects would be present.(AU)

Identifying critical state of breast cancer cell differentiation based on landscape dynamic network biomarkers / 生物医学工程学杂志

Breast cancer is a malignant tumor with the highest morbidity and mortality in female in recent years, and it is a complex disease that affects human health. Studies have shown that dynamic network biomarkers (DNB) can effectively identify critical states at which complex diseases such as breast cancer change from a normal state to a disease state. However, the traditional DNB method requires data from multiple samples in the same disease state, which is usually unachievable in clinical diagnosis. This paper quantitatively analyzes the time series data of MCF-7 breast cancer cells and finds the DNB module of a single sample in the time series based on landscape DNB (L-DNB) method. Then, a comprehensive index is constructed to detect its early warning signals to determine the critical state of breast cancer cell differentiation. The results of this study may be of great significance for the prevention and early diagnosis of breast cancer. It is expected that this paper can provide references for the related research of breast cancer.

Cytotoxic and Apoptotic properties of the Flavonoid-rich Ethyl Acetate fraction of the Crude Methanol Leaf Extract of Syzygium samarangense (Blume) Merr. (Myrtaceae) against MCF-7 Breast Cancer Cells

Introduction@#Breast cancer is the most common cancer among women in the Philippines and about 3 in every 100 Filipina will be diagnosed with breast cancer in their lifetime. There is a need to discover safe, yet inexpensive herbal extracts with potential cytotoxic properties as potential treatment modalities to treat breast cancer. @*Objectives@#This study seeks to explore the cytotoxic and apoptotic properties of the ethyl acetate fraction of the defatted crude methanol leaf extract of Syzygium samarangense in MCF-7 breast cancer cell lines. @*Methods@#Screening for flavonoids of the extracts was performed using TLC, total flavonoids, total phenols, FTIR and LC-MS spectroscopy. The hydrogen peroxide and ferric reducing anti-oxidant power were used as substrates to assess in vitro anti-oxidative properties of the extracts. The MTT dye viability assay was used to assess the cytotoxic properties of the extracts against MCF-7 cells. Apoptotic properties of the extracts in MCF-7 cells were determined by caspase-3 activation assay, DNA fragmentation patterns and fluorescence microscopy after annexin-V and propidium iodide staining. @*Results@#The abundance of flavonoids in the ethyl acetate fraction of the crude methanol leaf extract was established by TLC, FTIR, LC-MS/MS, total flavonoid and total phenol analyses. The in vitro anti-oxidative properties of this extract was comparable to ascorbic acid. The median inhibitory concentration (IC50) of this extract in MCF-7 breast cancer cell lines was 7.2 mcg/mL while doxorubicin registered an IC50 of 1.2 mcg/mL. At this concentration, the extract was not cytotoxic to normally-dividing breast epithelial cells. Cytotoxicity of the extract was mediated via apoptosis as demonstrated by DNA fragmentation, caspase-3 activation and fluorescence microscopic analyses. @*Conclusion@#The study shows that the flavonoid-rich ethyl acetate fraction of the crude methanol leaf extract of S. samarangense possesses potent apoptotic and cytotoxic properties against MCF-7 breast cancer cell lines at low concentrations.

MiR-4443 promotes migration and invasion of breast cancer cells by inhibiting PEBP1 expression / 南方医科大学学报

OBJECTIVE@#To investigate the effect of miR-4443 expression on migration and invasion of breast cancer.@*METHODS@#We examined the expression of miR-4443 in breast carcinoma in situ and paired adjacent tissues from 3 breast cancer patients with high-throughput sequencing and verified the results using TCGA database. We also detected miR-4443 expressions using real-time quantitative PCR (RT-qPCR) in low invasive and highly invasive breast cancer cells (MCF-7 and MDA-MB-231 cells, respectively). The changes in apoptosis, migration and invasion of MCF-7 and MDA-MB-231 cells after transfection with miR-4443 mimics, mimics-NC, miR-4443 inhibitor or inhibitor-NC were analyzed using flow cytometry, wound healing assay and Transwell invasion assay. The target gene of miR-4443 was predicted by bioinformatics software and validated by a dual luciferase reporter gene system. RT-qPCR and Western blotting were performed to detect the expression of recombinant human phosphatidyl ethanolamine binding protein 1 (PEBP1) in the transfected cells.@*RESULTS@#The expression of miR-4443 was significantly higher in the breast cancer tissues than in the adjacent tissues (@*CONCLUSIONS@#MiR-4443 promotes the migration and invasion of breast cancer cells by inhibiting the expression of PEBP1, suggesting the possibility of suppressing miR-4443 expression as a potential therapeutic strategy for breast cancer.

Enhanced production of glutaminase-free L-asparaginase by marine Bacillus velezensis and cytotoxic activity against breast cancer cell lines

Background: The increasing rate of breast cancer globally requires extraordinary efforts to discover new effective sources of chemotherapy with fewer side effects. Glutaminase-free L-asparaginase is a vital chemotherapeutic agent for various tumor malignancies. Microorganisms from extreme sources, such as marine bacteria, might have high L-asparaginase productivity and efficiency with exceptional antitumor action toward breast cancer cell lines. Results: L-Asparaginase-producing bacteria, Bacillus velezensis isolated from marine sediments, were identified by 16S rRNA sequencing. L-Asparaginase production by immobilized cells was 61.04% higher than that by free cells fermentation. The significant productivity of enzyme occurred at 72 h, pH 6.5, 37°C, 100 rpm. Optimum carbon and nitrogen sources for enzyme production were glucose and NH4Cl, respectively. L-Asparaginase was free from glutaminase activity, which was crucial medically in terms of their severe side effects. The molecular weight of the purified enzyme is 39.7 KDa by SDS-PAGE analysis and was ideally active at pH 7.5 and 37°C. Notwithstanding, the highest stability of the enzyme was found at pH 8.5 and 70°C for 1 h. The enzyme kinetic parameters displayed Vmax at 41.49 µmol/mL/min and a Km of 3.6 × 10−5 M, which serve as a proof of the affinity to its substrate. The anticancer activity of the enzyme against breast adenocarcinoma cell lines demonstrated significant activity toward MDA-MB-231 cells when compared with MCF-7 cells with IC50 values of 12.6 ± 1.2 µg/mL and 17.3 ± 2.8 µg/mL, respectively. Conclusion: This study provides the first potential of glutaminase-free L-asparaginase production from the marine bacterium Bacillus velezensis as a prospect anticancer pharmaceutical agent for two different breast cancer cell lines.

Triiodothyronine (T3) upregulates the expression of proto-oncogene TGFA independent of MAPK/ERK pathway activation in the human breast adenocarcinoma cell line, MCF7

ABSTRACT Objective: To verify the physiological action of triiodothyronine T3 on the expression of transforming growth factor α (TGFA) mRNA in MCF7 cells by inhibition of RNA Polymerase II and the MAPK/ERK pathway Materials and methods: The cell line was treated with T3 at a physiological dose (10−9M) for 10 minutes, 1 and 4 hour (h) in the presence or absence of the inhibitors, α-amanitin (RNA polymerase II inhibitor) and PD98059 (MAPK/ERK pathway inhibitor). TGFA mRNA expression was analyzed by RT-PCR. For data analysis, we used ANOVA, complemented with the Tukey test and Student t-test, with a minimum significance of 5%. Results: T3 increases the expression of TGFA mRNA in MCF7 cells in 4 h of treatment. Inhibition of RNA polymerase II modulates the effect of T3 treatment on the expression of TGFA in MCF7 cells. Activation of the MAPK/ERK pathway is not required for T3 to affect the expression of TGFA mRNA. Conclusion: Treatment with a physiological concentration of T3 after RNA polymerase II inhibition altered the expression of TGFA. Inhibition of the MAPK/ERK pathway after T3 treatment does not interfere with the TGFA gene expression in a breast adenocarcinoma cell line.

CoCl2 simulated hypoxia induce cell proliferation and alter the expression pattern of hypoxia associated genes involved in angiogenesis and apoptosis

BACKGROUND/AIMS: Hypoxia microenvironment plays a crucial role during tumor progression and it tends to exhibit poor prognosis and make resistant to various conventional therapies. HIF-1α acts as an important transcriptional regulator directly or indirectly associated with genes involved in cell proliferation, angiogenesis, apoptosis and energy metabolism during tumor progression in hypoxic microenvironment. This study was aimed to investigate the expression pattern of the hypoxia associated genes and their association during breast cancer progression under hypoxic microenvironment in breast cancer cells. METHODS: Cell proliferation in MCF-7 and MDA-MB-231 cell lines treated with different concentration of CoCl2 was analyzed by MTT assay. Flow cytometry was performed to check cell cycle distribution, whereas cell morphology was examined by phase contrast microscopy in both the cells during hypoxia induction. Expression of hypoxia associated genes HIF-1α, VEGF, p53 and BAX were determined by semiquantitative RT-PCR and real-time PCR. Western blotting was performed to detect the expression at protein level. RESULTS: Our study revealed that cell proliferation in CoCl2 treated breast cancer cells were concentration dependent and varies with different cell types, further increase in CoCl2 concentration leads to apoptotic cell death. Further, accumulation of p53 protein in response to hypoxia as compare to normoxia showed that induction of p53 in breast cancer cells is HIF-1α dependent. HIF-1α dependent BAX expression during hypoxia revealed that after certain extent of hypoxia induction, over expression of BAX conquers the effect of anti-apoptotic proteins and ultimately leads to apoptosis in breast cancer cells. CONCLUSION: In conclusion our results clearly indicate that CoCl2 simulated hypoxia induce the accumulation of HIF-1α protein and alter the expression of hypoxia associated genes involved in angiogenesis and apoptosis.