Cultured Breast Cancer Cells Research Articles

3D-printed transmembrane glycoprotein cancer biomarker aptasensor

Point-of-care, easy to manufacture, and low cost detection of cancer biomarkers is crucial for fighting the early stage disease. 3D printing allows delocalized printing at remote locations with updates/upgrades available globally via electronic files. Mucin 1 (MUC1) is a protein that is overexpressed in a number of epithelial cancers and is a key factor in advancement of the disease. Here we show the simple point-of-care 3D printing fabrication of a MUC1 aptasensor using a nanocarbon/polymer filament. Efficacy of the 3D-printed aptasensor is demonstrated by monitoring the expression and release of MUC1 in breast cancer cell cultures. Such a simple, low cost, and easy to locally fabricate cancer biosensor will have a large impact on the field of cancer diagnostics.

BSCI-16. Olfactory receptor 5B21 drives breast cancer metastasis

Olfactory receptors (ORs), responsible for the sense of smell, play an essential role in physiological processes (even outside the nasal epithelium) and cancer. In breast cancer, however, the expression and role of ORs remain understudied. We examined the significance of ORs transcript abundance in breast cancer metastasis to different tissues including the brain, bone, and lung. While we found 20 OR genes to be differentially expressed in different metastasis versus primary tumor, OR5B21 displayed high relation with all metastases. Knockdown of OR5B21 significantly decreased the invasion and migration of breast cancer cells in culture as well as metastasis to different organs including the brain, in vivo. On the other hand, overexpression of OR5B21 in the primary cells had the opposite effect. Mechanistically, OR5B21 was associated with epithelial to mesenchymal transition through STAT3/NFkB/CEBPβ signaling pathway. We propose OR5B21 (and potentially other ORs) as a novel oncogene contributing to breast cancer metastasis, and as a potential target for therapy.

Polypeptidic Taxol-Tropins: Targeting paclitaxel to the tumor microenvironment

Background and Rationale: Although PTX is widely used as a single chemotherapeutic agent and in various combination regimens, its clinical utility is hindered by acquired drug resistance and serious dose-limiting side effects that result from the ungoverned biodistribution of the taxane. Hypothesis: Conceptually, the precision, validity, and efficiency of paclitaxel delivery to tumor compartments might be substantially improved by “actively targeting” the exposed collagenous (XC-) proteins presented within the tumor microenvironment (TME)—XC-proteins physically exposed by the pathologic biochemical processes of tumor invasion, reactive stroma formation, and neo-angiogenesis. Objective: An adaptive bioengineering approach aims to apply pathotropic tumor-targeting functionality to paclitaxel (PTX), a powerful cytotoxic taxane which exhibits anti-tubulin / anti-mitotic / anti-cancer activities against a broad range of solid tumors. Materials and Methods: Synthetic peptide XC-targeting probes (< 40 aa) and polypeptide aptamers (40 to 53 aa), 85 - 99% purity, were prepared by 9-fluorenylmethyloxycarbonyl (Fmoc) solid phase peptide synthesis, purified by high performance liquid chromatography (HPLC), and verified by mass spectrometry and amino acid analysis, and the XC-targeting probes were FITC-labeled. Analysis of fluorescence in XC-binding assays was visualized with an Ultra Bright Blue Light trans-illuminator equipped with an amber filter; photo-documentation was provided by a Leica V-Lux 1 digital camera; and comparative fluorescence was quantified using a Quantus benchtop fluorimeter (Promega). The tumor-targeting properties of Taxol-Tropins were tested in vitro by Taxol-aptamer binding assays and collagen-agarose binding assays and the bioactivities of PTX bound non-covalently toTaxol-Tropin aptamers were tested on XC-agarose beads. Further, the tumor targeting property of the Taxol-Tropin aptamers was tested in vivo in a murine model of metastatic cancer. Results: Here we report on the first actively targeted delivery of paclitaxel utilizing bifunctional polypeptide targeting onco-aptamers, called Taxol-Tropins, which: (i) bind PTX upon simple mixing with suitably high affinities and; (ii) bind exposed XC-proteins, thereby promoting enhanced partitioning and drug delivery into the TME. The bifunctional peptide sequence-optimized Taxol-Tropins bound tightly non-covalently to PTX and also exhibited high affinity and selectivity for XC-agarose beads in vitro. Importantly, the cytotoxic bioactivity of the Taxol-Tropin-bound-PTX molecule was well preserved in cellulo, as was demonstrated by cytocidal activity observed in MDA-MB-231 breast cancer cell cultures. Tumor-targeted PTX delivery by Taxol-Tropin onco-aptamers in vivo was modeled by subcutaneous xenografts of human pancreatic cancer in nude mice: where intense fluorescence of the PTX probe was observed in tumors of mice injected with the Taxol-Tropin-bound-PTX within minutes after intravenous injection, but not in untreated mice or mice treated with non-targeted PTX probe. Conclusions: These results demonstrate the feasibility of pro-actively targeting PTX, a clinically important small molecule, using Taxol-Tropins: synthetic polypeptide onco-aptamers, revealing optimized drug binding sequences and structural modifications pertinent to further clinical development of the tumor-targeting platform which may indeed shift the Therapeutic Index of PTX to one of greater clinical efficacy at lower drug doses.

Polyphenol-Enriched Blueberry Preparation Controls Breast Cancer Stem Cells by Targeting FOXO1 and miR-145.

Scientific evidence supports the early deregulation of epigenetic profiles during breast carcinogenesis. Research shows that cellular transformation, carcinogenesis, and stemness maintenance are regulated by epigenetic-specific changes that involve microRNAs (miRNAs). Dietary bioactive compounds such as blueberry polyphenols may modulate susceptibility to breast cancer by the modulation of CSC survival and self-renewal pathways through the epigenetic mechanism, including the regulation of miRNA expression. Therefore, the current study aimed to assay the effect of polyphenol enriched blueberry preparation (PEBP) or non-fermented blueberry juice (NBJ) on the modulation of miRNA signature and the target proteins associated with different clinical-pathological characteristics of breast cancer such as stemness, invasion, and chemoresistance using breast cancer cell lines. To this end, 4T1 and MB-MDM-231 cell lines were exposed to NBJ or PEBP for 24 h. miRNA profiling was performed in breast cancer cell cultures, and RT-qPCR was undertaken to assay the expression of target miRNA. The expression of target proteins was examined by Western blotting. Profiling of miRNA revealed that several miRNAs associated with different clinical-pathological characteristics were differentially expressed in cells treated with PEBP. The validation study showed significant downregulation of oncogenic miR-210 expression in both 4T1 and MDA-MB-231 cells exposed to PEBP. In addition, expression of tumor suppressor miR-145 was significantly increased in both cell lines treated with PEBP. Western blot analysis showed a significant increase in the relative expression of FOXO1 in 4T1 and MDA-MB-231 cells exposed to PEBP and in MDA-MB-231 cells exposed to NBJ. Furthermore, a significant decrease was observed in the relative expression of N-RAS in 4T1 and MDA-MB-231 cells exposed to PEBP and in MDA-MB-231 cells exposed to NBJ. Our data indicate a potential chemoprevention role of PEBP through the modulation of miRNA expression, particularly miR-210 and miR-145, and protection against breast cancer development and progression. Thus, PEBP may represent a source for novel chemopreventative agents against breast cancer.

Abstract 2032: Vitamin B12 augments Ca2+ dependent cytotoxicity of diethyldithiocarbamate through excessive ER-vacuolization, oxidative stress and mitochondrial depolarization in MCF-7 cells in culture

Abstract Coordinated organization of intracellular organelles into functional networks is vital for cells. Mitochondrial and endoplasmic reticulum (ER) interaction in regulation of cell Ca2+ homeostasis is crucial for cell death and survival. Function of these intracellular organelles involved in two-way regulation of the status of major cell metabolites including protein, lipid exchange and intracellular Ca2+ homeostasis. Disulfiram and its derivatives recently attracted attention as a potential anticancer treatment (Kona et al., 2011). Combined use of hydroxycobalamin (vitamin B12b) and diethyldithiocarbamate (DDTC) demonstrated synergistic effect (combination index=0.25) and enhanced the cytotoxic effect of DDTC in number of transformed cell lines in culture (Solovieva et al., 2020). In the present work using MCF-7, human breast cancer cells in culture we demonstrate that combined action of DDTC and B12b resulted in induction of UPRER manifested by dilation of ER cisterns, increased level of polyubiquitinated proteins, and increased expression of CHOP. Confocal microscopy revealed disorganization of mitochondrial network and ER and treatment of these cells with B12b/DDTC and accompanied by mitochondrial depolarization (~50% after 6 h of exposure to drugs). Treatments also induced changes in morphology of mitochondrial network, and within 6 h of exposure, mitochondria demonstrated large amplitude swelling, characteristic feature of mitochondrial permeability transition pore opening. Drug exposure induced mitochondrial oxidative stress and increase in superoxide anion level (monitored with MitoSOX) and increased content of mitochondrial Ca2+ (xRhod-1) which almost doubled following treatment with B12b/DDTC. Short-time exposure of MCF-7 cells to mixture of drugs in Ca2+-free incubation media (2.5 mM EGTA) resulted in generation of significantly smaller size of vacuoles as compared with control. Similarly, pre-loading of cells with intracellular Ca2+ chelator (BAPTA, 5 µM, 30 min, 37oC) or inhibition of IP3 receptor(s) with 2-APB, delayed the drug-induced vacuolization. Taken together, our data indicate that the mechanism of B12b/DDTC-induced cytotoxicity in human MCF-7 cancer cell lines involves mitochondrial oxidative stress, activation of MPT pore and Ca2+ overload. Support of Funding Information: Russian Science Foundation № 19-75-20145 Citation Format: Marina E. Solovieva. Vitamin B12 augments Ca2+ dependent cytotoxicity of diethyldithiocarbamate through excessive ER-vacuolization, oxidative stress and mitochondrial depolarization in MCF-7 cells in culture [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2032.

Abstract 2888: Reversible and dose-dependent suppression of motility of human breast cancer cells with ONC201 and/or TR57 in culture

Abstract The cytotoxicity and cytostatic effects of imipridone family drugs ONC201 and its analog TR57 (Madera, USA) in variety of cultured breast cancer cell line (estrogen dependent BT474) was manifested through induction of ISR (Integrated Stress Response), UPRER and UPRMT. The major consequences of drug treatment are inhibition of proliferation and mitochondrial structural and functional damage(s). Our preliminary data demonstrated that 24 h exposure of BT474 leads to dysregulation and suppression in mitochondrial Ca2+ uptake and Ca2+ capacity (Odinokova et al., 2021). In the present work, we extend our study to include the effect of these drugs on the rate of migration intact and treated cells in culture. Treatment of BT474 cells in culture for 24h resulted in decreased motility of cells from 17 ± 2 µm/h in the absence of the drugs to 5 ± 1 µm/h and to 3±1 µm/h in cells treated with 10µM of ONC201 or 50nM of TR57 (n=5). This suppression was fully reversible and removal of drugs for 120h resulted in time dependent restoration of the initial motility of BT474 cells, and TR57 caused larger inhibitory effect on motility as compared with ONC201. Buffering of extracellular Ca2+ with 5 mM EGTA or intracellular Ca2+ with 10 µM BAPTA, 30 min suppressed motility of cells (19 ± 2 µm/h vs 6 ± 1 µm/h). Gd3+, selective blocker of store operated Ca2+ entrance (SOCE) pathway at concentration of 10 µM suppressed the motility of BT474 cells, and rate of migration changed for from 16 ± 2 µm/h in control to 7± 2 µm/h, in Gd3+ treated cells. In line with our preliminary data, taken together these data indicate that ONC201 and/or TR57 induced dysfunction in mitochondrial Ca2+ homeostasis, which translates into the suppression of the migration of human breast cancer cells in culture. Support of Funding Information: Russian Science Foundation № 19-75-20145 Citation Format: Yana Evstratova, Margarita Kobyakova, Irina Odinokova, Alexander Stolyarov, Artyom Mishukov, Lee M. Graves, Ekhson Holmuhamedov. Reversible and dose-dependent suppression of motility of human breast cancer cells with ONC201 and/or TR57 in culture [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2888.

Effect of ONC201 Antitumor Drug on the Number of Mitochondrial Nucleoids in BT474 Breast Cancer Cells in Culture

Effect of ONC201 Antitumor Drug on the Number of Mitochondrial Nucleoids in BT474 Breast Cancer Cells in Culture

Abstract 1416: Synergistic cytotoxicity of metformin cotreatment with paclitaxel or carboplatin in triple negative breast cancer cell lines

Abstract Metformin is an oral antidiabetic drug with a putative antineoplastic effect in breast cancer; however, its efficacy in clinical trials has been mixed. Triple negative breast cancer (TNBC) is an aggressive disease with poor outcomes for which new treatment strategies are needed. We aimed to define the pharmacological effect (synergistic, additive or antagonistic effect) of combination treatment with conventional chemotherapy agents (paclitaxel or carboplatin) and metformin in vitro. We carried out crystal violet cytotoxicity assays in primary breast cell lines derived from patients from our institution's breast cancer clinic (Luminal B cell lines: MBCD25 and MBCDF-D5; triple negative cell lines: MBCD11 and MBCDF-B4; epithelial phenotype: MBCD25 and MBCD11; mesenchymal phenotype: MBCDF-D5 and MBCDF-B4) and previously characterized triple negative breast cancer cell cultures (BRCA1WT: MDA-MB-231 and BRCA1-/-: HCC-1937) to estimate the EC50 for each cell line, drug and drug combination (paclitaxel + metformin and carboplatin + metformin). We used Chou and Talalay's method to estimate combination indices for each drug combination and cell line in Compusyn for Windows. Finally, we performed Western blot analysis to determine expression of Bcl-2, Bcl-xL, Bax, and Caspase 3 in each treatment condition. Sensitivity to each drug differs among the different cell lines. Sensitivity to paclitaxel is similar among all primary cell cultures and lowest in BRCAWT TBNC cell lines (EC50: MBCD25 0.46 µg/mL, MBCD11 0.26 µg/mL, MBCDF-D5 0.29 µg/mL, MBCDF-B4 0.24 µg/mL, MDA-MB-231 0.1 µg/mL, HCC-1937 0.77 µg/mL). Sensitivity to carboplatin is lowest amongst primary breast cultures with an epithelial phenotype, intermediate for cultures with a mesenchymal phenotype and in the BRCA1-/- TNBC cell line and highest in BRCAWT TNBC (EC50: MBCD25 36.84 µM, MBCD11 15.24 µM, MBCDF-D5 198.1 µM, MBCDF-B4 125.6 µM, MDA-MB-231 244 µM, HCC-1937 139.5 µM). Plotted combination indices show that cotreatment of paclitaxel with metformin is synergistic in all cell lines except MBCDF-B4. Cotreatment of carboplatin with metformin is synergistic in primary cell lines with an epithelial phenotype and in TNBC, especially in BRCA deficient cells. Expression of antiapoptotic proteins such as Bcl-2 correlated with higher drug resistance, but not with synergy or antagonism in combination with metformin. Combination treatment of primary breast cancer cultures and TNBC cell lines with metformin and carboplatin or paclitaxel has a variable pharmacological effect. TNBC cell lines were intrinsically drug resistant and metformin was effective in abrogating drug resistance. The high expression of antiapoptotic proteins of the Bcl-2 family in drug-resistant cell lines is remarkable due to the effectiveness of BH3 mimetics in hematologic malignancies and warrants further investigation in breast cancer. Citation Format: Ossian Longoria, José Esparza López, Eucario León-Rodríguez, María de Jesús Ibarra-Sánchez. Synergistic cytotoxicity of metformin cotreatment with paclitaxel or carboplatin in triple negative breast cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1416.

The PI3K/mTOR inhibitor Gedatolisib eliminates dormant breast cancer cells in organotypic culture, but fails to prevent metastasis in preclinical settings.

Dormant, disseminated tumor cells (DTCs) are thought to be the source of breast cancer metastases several years or even decades after initial treatment. To date, a selective therapy that leads to their elimination has not been discovered. While dormant DTCs resist chemotherapy, evidence suggests that this resistance is driven not by their lack of proliferation, but by their engagement of the surrounding microenvironment, via integrin‐β1‐mediated interactions. Because integrin‐β1‐targeted agents have not been translated readily to the clinic, signaling nodes downstream of integrin‐β1 could serve as attractive therapeutic targets in order to sensitize dormant DTCs to therapy. By probing a number of kinases downstream of integrin‐β1, we determined that PI3K inhibition with either a tool compounds or a compound (PF‐05212384; aka Gedatolisib) in clinical trials robustly sensitizes quiescent breast tumor cells seeded in organotypic bone marrow cultures to chemotherapy. These results motivated the preclinical study of whether Gedatolisib—with or without genotoxic therapy—would reduce DTC burden and prevent metastases. Despite promising results in organotypic culture, Gedatolisib failed to reduce DTC burden or delay, reduce or prevent metastasis in murine models of either triple‐negative or estrogen receptor‐positive breast cancer dissemination and metastasis. This result held true whether analyzing Gedatolisib on its own (vs. vehicle‐treated animals) or in combination with dose‐dense doxorubicin and cyclophosphamide (vs. animals treated only with dose‐dense chemotherapies). These data suggest that PI3K is not the node downstream of integrin‐β1 that confers chemotherapeutic resistance to DTCs. More broadly, they cast doubt on the strategy to target PI3K in order to eliminate DTCs and prevent breast cancer metastasis.

Bisacodyl in Stimulant Laxatives Can Induce Estrogen Agonist/Antagonist Activity in Breast Cancer Cells in Culture

Exposure to xenobiotic estrogens has the potential to induce estrogen activity that may contribute to a range of undesired physiological effects including the stimulation of estrogen responsive tumors. We have previously determined that extracts of OTC medications containing the stimulant laxative bisacodyl induce estrogenic activity in tissue culture bioassays. In this study, we tested the hypothesis that bisacodyl is responsible for the estrogen activity of these extracts and then characterized these effects. Ethanol extracts and dilutions were prepared from OTC medications containing Bisacodyl (1 gm:1 ml). The estrogen agonist and antagonist activity of each extract, as well as bisacodyl and then metabolite DA-bisacodyl was determined using the T47dkbluc estrogen reporter gene and the MCF-7 E3 estrogen responsive proliferation assays. LC-MS analysis was used to determine bisacodyl and DA-bisacodyl concentration in extracts as well as to trace the metabolism of bisacodyl to DA-bisacodyl in the cell culture bioassays. Molecular modeling “docking” simulations of the interactions of bisacodyl and the metabolite DA-bisacodyl with the estrogen receptor (ER) ligand binding domain was performed using MOE from Chemical Computing Group. Bisacodyl and the metabolite DA-bisacodyl induced mixed agonist/antagonist activity in MCF-7 E3 estrogen responsive proliferation assay similar to 4OH-tamoxifen. At the same time, both compounds stimulated only minimal estrogen activity in the T47dkbluc estrogen reporter gene assay. LC-MS analysis determinations identified that almost all bisacodyl was converted to the dihydroxy metabolite DA-bisacodyl in cell culture bioassays. Molecular modeling “docking” simulations determined that while bisacodyl does not fit into the agonist (estradiol) or antagonist (4OH-tamoxifen) conformations of the estrogen receptor ligand binding site, the metabolite DA-bisacodyl may fit into the antagonist induced binding pocket of the ER in a reasonable way. This study characterizes the observed estrogen activity of extracts from OTC medications containing bisacodyl as resulting from the bisacodyl metabolite DA-bisacodyl interacting with the estrogen receptor. Thus, bisacodyl is an OTC medication active ingredient that has potential to induce side effects and or toxicity involving estrogen signalling. The capacity for medications containing bisacodyl or other estrogenic substances to induce estrogen activity in patients is unclear. At the same time, consumers and practitioners should be aware of the potential estrogen activity of bisacodyl containing products.

Inhibition of the TGF‐beta Pathway Enhances the Tumoricidal Effect of Doxorubicin on Breast Cancer Cells

Triple negative breast cancer (TNBC) accounts for approximately 15% of all breast cancers but disproportionately accounts for the majority of breast cancer related deaths. As no specific signaling pathways driving TNBC growth have been established, chemotherapy with anthracycline drugs remains a mainstay of treatment. Although effective against TNBC, anthracyclines are known to cause dose limiting cardiac toxicity. We have previously shown that cardiovascular side effects of an anthracycline drug doxorubicin are mediated, at least in part, by the TGF-beta pathway. Therefore, we set out to determine if the TGF-beta signaling is upregulated in TNBC tissues, and suppression of this pathway impedes growth of TNBC cells. Using a database of 51 patients, we found that TNBC tumor samples were enriched for the TGF-beta pathway related transcripts, as compared to normal breast tissues. Furthermore, upregulated TGF-beta pathway related transcripts positively correlated with poor outcomes and, specifically, decreased survival of patients with TNBC. After this bioinformatic approach demonstrated a link between the TGF-beta pathway and TNBC progression, we assessed the effects of an ALK4/5/7 receptor kinase inhibitor SB431542, a known suppressor of the TGF-beta/Smad2/3 pathway, on proliferation and viability of cultured MDA-MB-231cells. Although effects of SB431542 alone were modest in this TNBC model system, its combination with an anthracycline drug doxorubicin more effectively suppressed viability of cultured breast cancer cells than either of these agents given alone. It appears that the enhanced tumoricidal effect of this drug combination was due to suppression of proliferation of MDA-MB-231 cells and not due to augmented apoptosis. Thus, the bioinformatic analysis of patients’ TNBC tissues transcriptome highlighted the role of the TGF-beta pathway in cancer progression. Complementing the doxorubicin treatment of the cultured TNBC model cells with an inhibitor of the TGF-beta pathway enhanced the tumoricidal effect of chemotherapy.

Influence of high-molecular hyaluronic acid on MCF-7 breast cancer stem cells

In recent years, more and more data have been accumulating on the high radio- and chemo-resistance of tumor stem cells (CSCs), confirming the assumption that these cells play an important role in the recurrence of the tumor process in some cancer patients. Therefore it is of considerable interest to elucidate the patterns and mechanisms of the formation of the CSC pool under the influence of various factors, including one of the main components of the extracellular matrix, hyaluronic acid (HA). The purpose of the study was to elucidate the effects of HA with a molecular weight of (1-3) x 106 Dа on the amount of CSCs in MCF-7 breast cancer cell culture in vitro. Material and methods. Using the MTT test, the viability of MCF-7 cancer cells was determined after incubation with HA at a concentration of 0.3-5.0 mg/ml. Using flow cytometry, we evaluated the change in the relative and absolute amount of CSCs under the influence of HA (0.6 mg/ml). CSCs were detected by CD44+CD24-/low immunophenotype, as well as by their ability to efficiently efflux Hoechst 33342 fluorescent dye from cells and form so-called side population (SP). Results. Viability of cancer cells in the general population decreased with increasing concentration of HA (R=-0.94, p=0.006). At the same time the incubation of cells with HA led to an increase in both the relative and absolute amounts of CSCs (SP) compared with the control. Thus, the relative number of SP cells increased by 2.0 times (p = 0.002), CD44 + CD24- / low cells - by 6.1 times (p = 0.005). The absolute number of these cells changed to a lesser extent compared to the control: the increase was 1.6 (p = 0.004) and 2.9 times (p = 0.02), respectively. Conclusion. Thus, the effect of high-molecular weight HA on breast cancer cells of MCF-7 line leads to an increase in amount of CSCs, while the viability of non-stem cancer cells decreases under the same conditions.

The investigation of the changes in the surface glycoconjugates using two different spheroid models of breast cancer cells and availability assessment of these spheroid models for rapid diagnosis

The importance of early cancer diagnosis has led to development of many different diagnostic methods. In this context, the studies investigating the presence and amount of sugar residues to use as indicators in the identification of cancer cell type have become prominent. In the present study, sialic acids found on the membrane surfaces of ER (+) MCF-7 and ER (-) MDA-MB-231 breast cancer cell lines were labeled using three-dimensional (3D) cell culture (Spheroid) model as the closest method to the patient sample, thus its natural environment, among the cell culture methods. These sugar units that play a role in regulation of important immune characteristics such as recognition, binding and metastasis were made visualizable by applying fluorescent-labeled lectins such as FITC-(Wheat Germ Agglutinin) specifically binding to sialic acid units (GlcNAc, Neu5Ac) including particularly ß-GlcNAc and FITC-(Maackia Amurensis-Lectin-1) specifically binding to Galß4GlcNAc type sialic acids. These glycan units were specifically labeled with FITC-(Maackia Amurensis-Lectin-1) and FITC- (Wheat Germ Agglutinin) and radiation intensities were analyzed relatively. The two different breast cancer cell cultures were compared with respect to change in the amounts of sialic acid residues containing α-2,3- and α-2,6 bonds using fluorescent-labeled lectins. In the present study, we have performed a precise, accurate and rapid determination of the sugar content in the different breast cancer cell surface lines by means of fluorescent-labeled lectins and carried out a relative comparison between the micrographs.

Carnitine palmitoyl transferase 1A is a novel diagnostic and predictive biomarker for breast cancer

BackgroundCarnitine palmitoyl transferase 1A (CPT1A), the key regulator of fatty acid oxidation, contributes to tumor metastasis and therapeutic resistance. We aimed to identify its clinical significance as a biomarker for the diagnosis and prediction of breast cancer.MethodsWestern blot, ELISA and in silico analysis were used to confirm CPT1A levels in breast cancer cell lines, cell culture medium and breast cancer tissues. Four hundred thirty breast cancer patients, 200 patients with benign breast disease, and 400 healthy controls were enrolled and randomly divided into a training set and a test set with a 7:3 ratio. Training set was used to build diagnostic models and 10-fold cross validation was used to demonstrate the performance of the models. Then test set was aimed to validate the effectiveness of the diagnostic models. ELISA was conducted to detect individual serum CPT1A levels. Receiver operating characteristic (ROC) curves were generated, and binary logistic regression analyses were performed to evaluate the effectiveness of CPT1A as a biomarker in breast cancer diagnosis. CPT1A levels between post-operative and pre-operative samples were also compared.ResultsCPT1A was overexpressed in breast cancer tissues, cell lines and cell culture medium. Serum CPT1A levels were higher in breast cancer patients than in controls and were significantly associated with metastasis, TNM stage, histological grading and molecular subtype. CPT1A levels were decreased in post-operative samples compared with paired pre-operative samples. Moreover, CPT1A exhibited a higher efficacy in differentiating breast cancer patients from healthy controls (training set: area under the curve, AUC, 0.892, 95% CI, 0.872–0.920; test set, AUC, 0.904, 95% CI, 0.869–0.939) than did CA15–3, CEA, or CA125.ConclusionCPT1A is overexpressed in breast cancer and can be secreted out of breast cancer cell. Serum CPT1A is positively associated with breast cancer progression and could serve as an indicator for disease monitoring. Serum CPT1A displayed a remarkably high diagnostic efficiency for breast cancer and could be a novel biomarker for the diagnosis of breast cancer.

Inhibition of aquaporins as a potential adjunct to breast cancer cryotherapy.

Cryoablation is an emerging type of treatment for cancer. The sensitization of tumors using cryosensitizing agents prior to treatment enhances ablation efficiency and may improve clinical outcomes. Water efflux, which is regulated by aquaporin channels, contributes to cancer cell damage achieved through cryoablation. An increase in aquaporin (AQP) 3 is cryoprotective, whereas its inhibition augments cryodamage. The present study aimed to investigate aquaporin (AQP1, AQP3 and AQP5) gene expression and cellular localization in response to cryoinjury. Cultured breast cancer cells (MDA-MB-231 and MCF-7) were exposed to freezing to induce cryoinjury. RNA and protein extracts were then analyzed using reverse transcription-quantitative PCR and western blotting, respectively. Localization of aquaporins was studied using immunocytochemistry. Additionally, cells were transfected with small interfering RNA to silence aquaporin gene expression and cell viability was assessed using the Sulforhodamine B assay. Cryoinjury did not influence gene expression of AQPs, except for a 4-fold increase of AQP1 expression in MDA-MD-231 cells. There were no clear differences in AQP protein expression for either cell lines upon exposure to frozen and non-frozen temperatures, with the exception of fainter AQP5 bands for non-frozen MCF-7 cells. The exposure of cancer cells to freezing temperatures altered the localization of AQP1 and AQP3 proteins in both MCF-7 and MDA-MD-231 cells. The silencing of AQP1, AQP3 and AQP5 exacerbated MDA-MD-231 cell damage associated with freezing compared with control siRNA. This was also observed with AQP3 and AQP5 silencing in MCF-7 cells. Inhibition of aquaporins may potentially enhance cryoinjury. This cryosensitizing process may be used as an adjunct to breast cancer cryotherapy, especially in the border area targeted by cryoablation where freezing temperatures are not cold enough to induce cellular damage.

A Lung Organotypic Coculture Reveals a Role for TFEB-Lysosomal Axis in the Survival of Disseminated Dormant Cancer Cells.

Simple SummaryOne of the worst aspects of tumors is the relapse of metastatic lesions several years after the removal of the primary tumor and after the patient has been considered disease-free. This particular aspect is called “metastatic dormancy”. Unfortunately, this behavior is particularly hard to study because disseminated cancer cells are technically not detectable by current imaging techniques. We developed a culture of breast cancer cells and lung epithelial cells that recapitulates in vitro several aspects of what is observed in the real lung. With this tool we identified a specific feature: a lysosomal process that is activated in breast cancer cells and which might be used in the future to target those cells before they wake up.(1) Background: metastatic relapse following a prolonged period of disease-free survival is a common cause of mortality for many cancer patients. Disseminated dormant cancer cells (DDCCs) lie below the radar before waking up years, or even decades, after the removal of the primary tumor. This implies that they are able to survive in a latent state in a foreign environment for an extended period of time supported by intrinsic and extrinsic factors still to be elucidated. (2) Methods: we employed a coculture of DDCCs with lung epithelial cells together with RNA sequencing analysis to understand the overlap in gene transcription between in vivo and cocultured DDCCs. (3) Results: we found a significant overlap between the processes activated in DDCCs from lungs and in the coculture, as well as in alveolar type I cells in vivo and in coculture. We identified the transcription factor EB (TFEB)-lysosomal axis as a relevant process activated in DDCCs upon dissemination to the lung and confirmed the results in our lung coculture. Interestingly, breast cancer patients with a higher expression of TFEB targets show increased likelihood of developing relapses. (4) Conclusions: we propose that lysosomal accumulation following TFEB activation is an important feature of breast cancer DDCCs that might be exploited for future therapeutic interventions.

A not so worthless attempt to develop primary culture from breast FNAC/CNB samples!

Breast cancer is the second leading death-causing cancer in women. Since a longtime, continuous breast cancer cell lines have been used for drug discovery based research. However, these cell lines may not represent the characteristics of original as they are believed to undergo changes due to repeated passaging. Primary cultures directly obtained from the tumor are gaining more attention worldwide as these are believed to mimic the disease process more accurately than that of continuous cell lines. The major problem with the usage of primary culture is to get the sufficient number of cells for the experiments. Here, in this study we attempted to develop primary culture both from FNAC and core needle biopsy (CNB) samples of the breast cancer patients. Overall, we believe that it is not so difficult to establish primary cultures of breast cancer cells from clinical FNAC/CNB samples. However, the starting population in FNAC samples is less which can be a hindrance in getting an adequate number of cells to reach a monolayer. CNB samples may be better quantitatively and stepwise troubleshooting of problems faced can help in the successful establishment of monolayer and primary cultures that can be propagated. We believe, our experience might be helpful for those who are struggling with the development of the short-term primary culture of breast cancer from the small-sized tissue samples.

Perfusion Flow Enhances Viability and Migratory Phenotype in 3D-Cultured Breast Cancer Cells

Conventional 2D cell culture, a traditional tool in pre-clinical studies, can hardly be regarded as a representation of a natural cell microenvironment. In this respect, it might result in altered cellular behaviors. To overcome such a limitation, different approaches have been tested to conduct more representative in vitro studies. In particular, the use of 3D cell culture introduces variables, such as cell-cell and cell-extracellular matrix interactions; cell features such as survival, proliferation and migration are consequently influenced. For an example, an enhanced drug resistance and increased invasiveness are shown by cancer cells when cultured in 3D versus 2D conventional culture models. In this setting however, non-uniform cell distribution and biological behaviors appear throughout the scaffold, due to reduced diffusion of oxygen and nutrients. Perfusion in bioreactor systems can be used to improve medium transport. In this line of reasoning, this study proposes a breast cancer cell culture model sustained by an integrated approach that couples a 3D environment and a fluid perfusion. This model improves viability and uniformness of cell distribution, while inducing morphological, functional and molecular cancer cell remodeling.

Phytochemical screening and cytotoxic evaluation of Bauhinia scandens leaf extracts using HeLa and T47D cell lines

Abstract. Lianah L, Khasanah RAN, Pranatami DA, Krisantini K. 2021. Phytochemical screening and cytotoxic evaluation of Bauhinia scandens leaf extracts using HeLa and T47D cell lines. Biodiversitas 22: 913-919. The aim of the study was to analyze the phytochemical contents and todetermine the cytotoxic activities of Bauhinia scandens leaf ethanol extracts against HeLa (human cervical cancer) and T47D (breast cancer) cell culture lines. Using a standard protocol, it was found that leaf extract of B. scandens contains phytochemicals that are widely known to have medicinal properties, such as phenols (17.57±0.098% w/w), flavonoids (5.91±0.098% w/w), saponins (19.42±0.091% w/w), tannins (1.24±0.035% w/w), alkaloids (1.31±0.001% w/w) and steroids (0.08±0.007% w/w). Results of 24-hr Microculture Tetrazolium Salt (MTT) assay show that leaf extracts of B. scandens can suppress cell growth at a half-maximal inhibitory concentration (IC50) of 1.95 μg/mLfor HeLa cells and 4.54μg/mL for T47D cells. This indicates that B. scandens is a potentially strong candidate for anti-cancer agents. The cytotoxic activities of the leaf extracts of B. scandens can be attributed to the total effects of the phytochemical compounds found. Further studies are recommended in order to isolate and determine individual effects of bioactive compounds in B. scandens.

Nitrosonium Cation as a Cytotoxic Component of Dinitrosyl Iron Complexes with Thiol-containing Ligands (based on the Experimental Work on MCF7 Human Breast Cancer Cell Culture).

Here we demonstrate that binuclear dinitrosyl iron complexes with thiol-containing ligands (glutathione and mercaptosuccinate, B-DNIC-GSH and B-DNIC-MS, respectively) exert cytotoxic effects on MCF7 human breast cancer cells. We showed that they are mediated by nitrosonium cations released from these complexes (NO+). This finding is supported by the cytotoxic effect of both B-DNICs on MCF7 cells evidenced to retain or was even promoted in the presence of N-Methyl-D-glucamine dithiocarbamate (MGD). MGD recruits an iron nitrosyl group [Fe(NO)] from the iron-dinitrosyl fragment [Fe(NO)2] of B-DNIC-MS forming stable mononitrosyl complexes of iron with MGD and releasing NO+ cations from a [Fe(NO)2] fragment.