MDA-MB231 Cell Lines Research Articles

PFDN4 as a Prognostic Marker Was Associated with Chemotherapy Resistance through CREBP1/AURKA Pathway in Triple-Negative Breast Cancer.

Breast cancer is the most common malignancy and its incidence is increasing. It is currently mainly treated by clinical chemotherapy, but chemoresistance remains poorly understood. Prefolded proteins 4 (PFDN4) are molecular chaperone complexes that bind to newly synthesized polypeptides and allow them to fold correctly to stabilize protein formation. This study aimed to investigate the role of PFDN4 in chemotherapy resistance in breast cancer. Our study found that PFDN4 was highly expressed in breast cancer compared to normal tissues and was statistically significantly associated with stage, nodal status, subclasses (luminal, HER2 positive and triple negative), triple-negative subtype and disease-specific survival by TCGA database analysis. CRISPR knockout of PFDN4 inhibited the growth of 89% of breast cancer cell lines, and the triple-negative cell line exhibited a stronger inhibitory effect than the non-triple-negative cell line. High PFDN4 expression was associated with poor overall survival in chemotherapy and resistance to doxorubicin and paclitaxel through the CREBP1/AURKA pathway in the triple-negative MDAMB231 cell line. This study provides insightful evidence for the value of PFDN4 in poor prognosis and chemotherapy resistance in breast cancer patients.

In vitro ANTI-CANCER EFFECTS OF QUERCETIN ON TRIPLE NEGATIVE BREAST CANCER CELL LINE

Phytochemicals are widely being explored for their cancer preventive properties in today’s oncotherapy. Quercetin is a major constituent of various dietary products and its anti-cancer potential was explored on different cancer cell lines. The present study was conducted to find out the anti-proliferative effects of quercetin on human triple negative breast cancer cell line MDA-MB The anti-cancer potential of quercetin, nano-quercetin and doxorubicin at various concentrations were assessed by cellular cytotoxicity (MTT) assay. The IC50 values of quercetin, nano-quercetin and doxorubicin on MDA-MB 231 cell line were 394.8, 204.6 and 17.17 μM, respectively. In vitro anti-cancer effects of these drugs were manifested as apoptosis and cellular toxicity. The cytotoxicity was moderate in quercetin, remarkable in nano-quercetin and strong in doxorubicin treatments. The in vitro anti-cancer effect of quercetin was comparable with the standard drug doxorubicin. Considering the potential side effects of doxorubicin, the quercetin might be explored with further studies in the treatment of mammary tumours in animals and humans.

Abstract 1670: Mechanistic insight into mTOR signaling identifies RNA splicing machinery as a potential therapeutic target for cancer

Abstract Aberrant signal transduction regulating cell growth and proliferation is a hallmark of many cancers. Activation of mTOR signaling is common and is an attractive therapeutic target with mechanistically different mTOR inhibitors in clinical use. One consequence of exposure to the mTOR inhibitor rapamycin is an alteration of gene expression through a global increase in alternative exon inclusion (Cheng et al. 2022, doi.org/10.3390/ijms232012416). To examine the mechanisms underlying this effect, we utilized the TempO-Seq targeted sequencing platform to profile both the whole transcriptome and a selection of alternatively spliced RNA targets in the rapamycin sensitive and resistant breast cancer cell lines MCF-7 and MDA MB 231 following exposure to 13 mTOR inhibitors, some closely related and some from distinct chemical classes. Recent publications have demonstrated that high quality dose response data can be obtained using this sequencing platform (Harrill et al. 2021, doi: 10.1093/toxsci/kfab009; Ramaiahgari et al. 2019, doi: 10.1093/toxsci/kfz065) and TempO-Seq has been widely adopted in toxicology for deriving compound-specific expression signatures to identify mechanisms of action and long-term toxicity. Treated cells were also profiled using TempO-LINC, a novel high-throughput single-cell assay based on the same platform. We observed that certain mTOR inhibitors induced both common and cell-specific differential expression as well as widespread alternative exon inclusion, as expected. Intriguingly, transcripts with the most significant changes in splicing upon treatment were those encoding members of the SR family of splicing factors, often overexpressed or amplified in breast cancers (Park, et al. 2019, doi: 10.1016/j.celrep.2019.10.110). This is significant because SR protein expression is autoregulated by alternative inclusion of an exon containing a premature stop codon in a feedback loop leading to nonsense-mediated decay (NMD) and lowered protein levels. Indeed, NMD is known to be inhibited by rapamycin (Martinez-Nunez, et al. 2017, doi: 10.1093/nar/gkw1109), which would lead to the observed accumulation of these transcripts. Thus, monitoring a targeted selection of alternative splicing events and regulators revealed mTOR regulation of mRNA isoform abundance consistent with regulation of the NMD RNA turnover process and with overexpression of SR proteins in breast cancers. Importantly, targeted bulk and single-cell TempO-Seq assays enable efficient sequencing and simplified data analysis without the expense and bioinformatic burden of RNAseq, making them particularly well-suited for drug discovery. These results support the use of this approach for further characterization of cell-specific effects of mTOR inhibitors and their mechanisms of action. Citation Format: Gaelle Rondeau, Megan Opichka, Kevin White, Joanne M. Yeakley, Dennis J. Eastburn, Bruce Seligmann. Mechanistic insight into mTOR signaling identifies RNA splicing machinery as a potential therapeutic target for cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1670.

Abstract 6429: Critical role of elevated TMEM176B gene expression in humanized patient-derived xenografts mouse models of triple negative breast cancer

Abstract Objective: In the cancer research, a highly promising in vivo platform for personalized treatment involves the adoption of an advanced approach—specifically, the grafting of patient-derived xenografts (PDX) onto humanized mouse models. These models capture distinctive aspects of interaction with the human immune system and the tumor microenvironment (TME). In this study, we have engineered humanized triple-negative breast cancer (TNBC) PDX models to observe alterations in differentially expressed genes, thereby enhancing our understanding of the intricacies of personalized treatment in this context. Method: We utilized two TNBC PDX models established for the humanized models, where CD34+ hematopoietic stem cells were transplanted into immunodeficient mice. RNA sequencing was performed to identify altered gene expression in humanized PDX models compared to NSG PDXs. Additionally, we generated stable cell lines overexpressing TMEM176B in MDAMB231 and Hs578T cells, and we knocked down TMEM176B in 4T1 cells using recombinant techniques Results: In the humanized model, the growth of PDX tumors did not show a significantly faster or markedly different rate compared to previous studies. However, upon conducting RNA sequencing in the PDX model, the expression of the TMEM176B gene was consistently downregulated. Consequently, we transfected and observed that the increased expression of TMEM176B in MDAMB231 and Hs578T cell lines resulted in enhanced cell proliferation in vitro. Transplanting MDAMB231 cells overexpressing TMEM176B into athymic nude mice resulted in accelerated tumor growth. The study further investigates the expression of TMEM176B in an immune-competent environment by knocking down the gene in 4T1 cells or transplanting the control group into a balb/c mouse model. Tumors with TMEM176B knockdown exhibited inhibited growth, increased CD3+ T cell infiltration, and significant inhibition when treated with anti-PD-L1 compared to the control group. Conclusion: This research demonstrates the utility of PDX models, particularly humanized PDX models, in studying the complexities of cancer biology and the tumor microenvironment. The findings regarding TMEM176B and its role in tumorigenesis and immune responses in triple-negative breast cancer provide valuable insights for further research and potential therapeutic interventions. Citation Format: Yujeong Her, Jihui Yun, Woohang Heo, Jong-Il Kim, Han-Byoel Lee, Wonshik Han, Hyeong-Gon Moon. Critical role of elevated TMEM176B gene expression in humanized patient-derived xenografts mouse models of triple negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6429.

Abstract 1992: A novel RB1 E3 ligase TRIM37 contributes to palbociclib resistance in breast cancer

Abstract The tripartite motif-containing 37 (TRIM37) is a RING finger E3 ubiquitin ligase and is a poor prognostic factor in breast cancer patients. The gene is located in chromosome 17q23, a region amplified in up to 40% of breast cancers. We observed that activation of androgen receptor (AR) could induce resistance to the CDK4/6 inhibitor Palbociclib, the mechanism yet to be clarified. ChIP-sequencing data suggested that AR binds to the TRIM37 promoter, with AR activation resulting in TRIM37 expression. We hypothesized that TRIM37 might be involved in Palbociclib resistance. Using an ER+ve cell line MCF7 and a TNBC cell line MDA-MB 453, we found that overexpression of TRIM37 could induce Palbociclib resistance. TRIM37 overexpression resulted in RB1 protein downregulation, which is the primary downstream target of CDK4/6, while TRIM37 knockdown enhanced RB1 protein expression. Ubiquitination assay demonstrated TRIM37 overexpression increased the level of RB1 protein ubiquitination. The co-immunoprecipitation (Co-IP) assay confirmed that TRIM37 protein could interact with the RB1 protein. These results suggest that TRIM37 could be the E3 ligase that regulates RB1 degradation. Various deletion mutants of TRIM37 were cloned for Co-IP experiments between these mutants and RB1. Results show that the MATH and c-terminal domains of TRIM37 was the essential region for the interaction. Overexpression of the mutant with the TRIM37 MATH and c-terminal domains (TRIM37-MATH/C) could enhance RB1 protein level. This might be due to competition of TRIM37-MATH/C with wild-type TRIM37 for RB1 binding. Our findings suggest TRIM37 is a novel RB1 E3 ligase, and it binds to the RB1 protein via the MATH and C-terminal domains to regulate protein degradation. Our study also suggests that high expression of TRIM37 mediated by AR activation could deplete RB1, which is the target of Palbociclib, eventually leading to resistance. These findings are supportive of the contribution of AR activation to Palbociclib resistance. Citation Format: Chanping You, Ho Tsoi, Pui Sum Man, Larry Ka Yue Chow, Wei Dai, Ui Soon Khoo. A novel RB1 E3 ligase TRIM37 contributes to palbociclib resistance in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1992.

Abstract 1550: Identification of a novel squalene epoxidase function in breast cancer brain metastasis

Abstract Brain metastases are serious complications of breast cancer, especially in triple-negative breast cancer (TNBC) patients. There is currently no effective treatment due to the unique brain microenvironment and limitation for drugs to cross the blood-brain barrier (BBB). BBB limits access of nutrients from the circulation and thereby makes the brain hypoxic and depleted of metabolites, growth factors and proteins. However, it remains poorly understood how breast cancer cells manipulate for adaption and colonization in the brain. To probe the molecular mechanism of breast cancer brain metastasis (BCBM), we compared gene signatures in primary breast tumors and BCBM tumors, and identified that SQLE (encodes squalene epoxidase, the second rate-limiting enzyme in the cholesterol biosynthesis) could be a leading-edge gene in breast cancer brain metastasis. To explore the role of SQLE in BCBM, we established the brain metastatic TNBC MDA-MB-231 (MDA231-BrM) cell line from brain metastatic subpopulation that originated from its parental MDA-MB-231 (MDA231) cell line. We found that SQLE expression was greatly upregulated in MDA231-BrM cells compared with the parental MDA231 cells. Using MDA231-BrM and MDA231 cell lines expressing SQLE shRNAs, we evaluated the effects of SQLE loss on cancer cell migration, invasion, and stemness by wound-healing, transwell invasion/migration, and tumorsphere formation assays. While loss of SQLE greatly attenuated cell invasiveness and stemness in both MDA231 and MDA231-BrM cells, loss of SQLE could only affect the cell migration activity on MDA231 cells but not MDA231-BrM cells. Our RNA-seq data further identified a subset of SQLE-affected genes that is uniquely enriched in MDA231-BrM cells and favors brain extravasation and colonization. To explore the potential function of SQLE in brain extravasation and colonization, we established in vitro BBB models and ex vivo mouse brain slice organotypic cultures. We showed that loss of SQLE inhibited the ability of MDA231-BrM cells to across the BBB-mimic astrocyte-endothelial structures as well as impaired the co-option with blood capillaries in the mouse brain slices. Although SQLE-deficient MDA231-BrM cells could still spread on the surface of the blood vessels, they seemed to undergo apoptosis. Since the ability to invade, migrate, and penetrate is critical for invasion of cancer cells, our results strongly imply the novel function of SQLE in breast cancer cell invasion, penetration, and even colonization in the brain through blood vessel co-option. In summary, our data reveal a novel role for SQLE in two critical requisites for breast-to-brain extravasation and colonization - the ability to penetrate through BBB and to co-opt brain vessels for metastatic expansion. Our findings indicate that targeting SQLE may represent a therapeutic opportunity for breast cancer brain metastases. Citation Format: Shu-Ping Wang, Jia-Yun Yeh, Yu-Ling (Pony) Lee, Kun-Yuan Lin, Chao-Di Chang, Chih-Chieh Yang, Shan-Yun Cheng, Ya-Wen Hung, Yu-Hsien Chang, Yao-Feng Li, Yung-Lung Yu. Identification of a novel squalene epoxidase function in breast cancer brain metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1550.

Anticancer potential of toxin extracts from vital organs of milk spotted puffer fish Chelonodon patoca on human cancer cell lines

Among aquatic creatures, fish are the most diversified organisms that have emerged among other vertebrates. The objective of this research was to evaluate the anticancer properties of toxin extracts from the marine puffer fish Chelonodon patoca. The toxins were extracted from the samples by homogenizing with acetic acid, and the clear supernatant was subjected to anticancer activities by MTT for cytotoxicity and cell viability on both Vero and cancer cell lines (A-549, AGS, HT-29, and MDA-MB-231). More than 70% of the normal cells were viable up to 200 µg/ml of toxin extracts so that hence the concentration was fixed below 200 µg/ml for the cell viability study on human cancer cells. Among the various organs, the toxin extracted from the liver showed potential antiproliferative activity at an inhibitory concentration of 50 µg/ml on HT-29 and MDA-MB231cell lines, 75 µg/ml on A549 and 100 µg/ml on AGS. The cellular and nuclear morphological changes, induction of apoptosis, and its stages were observed microscopically through different staining methods. Further, the DNA damage was confirmed by DNA fragmentation analysis to confirm apoptosis. The results suggest that the extract of toxin (liver) shows a significant antiproliferative effect on the human cancer cell lines.

Synthesis of Self Permeable Antisense PMO Using C5-Guanidino-Functionalized Pyrimidines at the 5'-End Enables Sox2 Downregulation in Triple Negative Breast Cancer Cells.

Delivery of macromolecular drugs inside cells has been a huge challenge in the field of oligonucleotide therapeutics for the past few decades. Earliest natural inspirations included the arginine rich stretch of cell permeable HIV-TAT peptide, which led to the design of several molecular transporters with varying numbers of rigid or flexible guanidinium units with different tethering groups. These transporters have been shown to efficiently deliver phosphorodiamidate morpholino oligonucleotides, which have a neutral backbone and cannot form lipoplexes. In this report, PMO based delivery agents having 3 or 4 guanidinium groups at the C5 position of the nucleobases of cytosine and uracil have been explored, which can be assimilated within the desired stretch of the antisense oligonucleotide. Guanidinium units have been connected by varying the flexibility with either a saturated (propyl) or an unsaturated (propargyl) spacer, which showed different serum dependency along with varied cytoplasmic distribution. The effect of cholesterol conjugation in the delivery agent as well as at the 5'-end of full length PMO in cellular delivery has also been studied. Finally, the efficacy of the delivery has been studied by the PMO mediated downregulation of the stemness marker Sox2 in the triple-negative breast cancer cell line MDA-MB 231. These results have validated the use of this class of delivery agents, which permit at a stretch PMO synthesis where the modified bases can also participate in Watson-Crick-Franklin base pairing for enhanced mRNA binding and protein downregulation and could solve the delivery problem of PMO.

The Effect of 4-(Dimethylamino)phenyl-5-oxopyrrolidines on Breast and Pancreatic Cancer Cell Colony Formation, Migration, and Growth of Tumor Spheroids.

A series of hydrazones, azoles, and azines bearing a 4-dimethylaminophenyl-5-oxopyrrolidine scaffold was synthesized. Their cytotoxic effect against human pancreatic carcinoma Panc-1 and triple-negative breast cancer MDA-MB-231 cell lines was established by MTT assay. Pyrrolidinone derivatives 3c and 3d, with incorporated 5-chloro and 5-methylbenzimidazole fragments; hydrazone 5k bearing a 5-nitrothien-2-yl substitution; and hydrazone 5l with a naphth-1-yl fragment in the structure significantly decreased the viability of both cancer cell lines. Compounds 3c and 5k showed the highest selectivity, especially against the MDA-MB-231 cancer cell line. The EC50 values of the most active compound 5k against the MDA-MB231 cell line was 7.3 ± 0.4 μM, which were slightly higher against the Panc-1 cell line (10.2 ± 2.6 μM). Four selected pyrrolidone derivatives showed relatively high activity in a clonogenic assay. Compound 5k was the most active in both cell cultures, and it completely disturbed MDA-MB-231 cell colony growth at 1 and 2 μM and showed a strong effect on Panc-1 cell colony formation, especially at 2 μM. The compounds did not show an inhibitory effect on cell line migration by the 'wound-healing' assay. Compound 3d most efficiently inhibited the growth of Panc-1 spheroids and reduced cell viability in MDA-MB-231 spheroids. Considering these different activities in biological assays, the selected pyrrolidinone derivatives could be further tested to better understand the structure-activity relationship and their mechanism of action.

Functionalization of Carbon Nanotubes Loaded with Tamoxifen and Their Anticancer Potential against Human Breast Cancer Cells Review

Background & Objectives: Carbon nanotubes (CNTs) serve as molecular carriers for in vivo and in vitro delivery. Initial studies have suggested that nanotubes in drug delivery can enhance the therapeutic response to anti-cancer drugs. The present study intended to investigate the effect of CNTs carrying tamoxifen (TAM-CNTs) on the induction of apoptosis in the MDAMB-231 cell line. Materials & Methods: The cells were treated with various concentrations of TAM and TAMCNTs. The IC50 for these compounds was determined using a MTT assay. The cells were then treated with a lower concentration of IC50. The BAX and BCL-2 genes expression were evaluated by Real-Time PCR and Western blot. Flow cytometry was employed for evaluating apoptosis induction by TAM and TAM-CNTs. Results: The IC50 value of TAM and TAM-CNTs in a 48-hour period was 66.19 mg/mL and 36.59 mg/mL, respectively. The results demonstrated that BAX in the cells treated with TAM and TAM-CNTs was upregulated 3.64 and 7.88 times, respectively (P <0.05). Conversely, BCL-2 was downregulated 3.98 and 5.31 times (P <0.05). Furthermore, Western blot experiments confirmed the expression of BAX and BCL-2 proteins based on their gene expression. Flow cytometry results indicated that the viability of MDA-MB-231 cells in the control group, TAM-treated, and TAM-CNTs-treated cells was 95.3%, 64.9%, and 13.75%, respectively. This suggests that TAM-CNTs significantly diminishes cell viability compared to TAM (P <0.001). Conclusion: The findings revealed that TAM accompanied by CNTs exhibits a greater cytotoxic and apoptotic effect on MDA-MB-231 cells.

Distinctive Expression of MetastamiRs in Breast Cancer Mesenchymal Stem Cells Isolated from Solid Tumor.

MSCs are a part of the tumor microenvironment, which secrete cytokines and chemokines. They can affect metastasis and the growth of tumors. metastamiRs are newly recognized regulatory elements of the metastasis pathway which are involved in epithelial-to-mesenchymal transition (EMT). In the present study, we aimed to assess the expression profile of metastamiRs in the context of MSCs in correlation with their invasion and migration power. Tumor-isolated BC-MSCs and normal human mammary epithelial cells (HMECs) along with MCF-7, MDA-MB231, and MCF-10A cells were prepared and confirmed for their identity. The cells were assessed for CD44+CD24¯ percentage, Oct-4, and Survivin expression. GEO, KEGG, and TCGA databases were investigated to detect differential miR-expressions. Real- time PCR for 13 miRs was performed using LNA primers. Ultimately, Transwell-Matrigel assays as used to assess the level of migration and invasion. Our results indicated that some oncomiRs like miR-10b were upregulated in BC-MSCs, while the levels of miR-373 and miR-520c were similar to the MCF-10A. Generally, miR-200 family members were on lower levels compared to the other miR-suppressor (miR-146a, 146b, and 335). miR-31 and 193b were up-regulated in MCF-10A. The most invasiveness was observed in the MDA-MB231 cell line. We have demonstrated that the miR-expression levels of BC-MSCs are somewhat in between MCF-7 and MDA-MB231 miR-expression levels. This could be the logic behind the moderate level of invasion in BC-MSCs. Therefore, miR-therapy approaches such as miR-mimic or antagomiRs could be used for BC-MSCs in clinical cancer therapy.

Copper-catalyzed synthesis of pyrazolo[1,5-a]pyrimidine based triazole-linked glycohybrids: mechanistic insights and bio-applications

Hybrid molecules maintain their stronghold in the drug market, with over 60% of drug candidates in pharmaceutical industries. The substantial expenses for developing and producing biologically privileged drugs are expected to create opportunities for producing hybrid molecule-based drugs. Therefore, we have developed a simple and efficient copper-catalyzed approach for synthesizing a wide range of triazole-linked glycohybrids derived from pyrazolo[1,5-a]pyrimidines. Employing a microwave-assisted copper-catalyzed approach, we developed a concise route using various 7-O-propargylated pyrazolo[1,5-a]pyrimidines and 1-azidoglycosides. This strategy afforded a series of twenty-seven glycohybrids up to 98% yield with diverse stereochemistry. All were achieved within a remarkably shortened time frame. Our investigation extends to evaluating the anticancer potential of these synthesized triazole-linked pyrazolo[1,5-a] pyrimidine-based glycohybrids. In-vitro assays against MCF-7, MDA-MB231, and MDA-MB453 cell lines reveal intriguing findings. (2R,3S,4S,5R,6R)-2-(acetoxymethyl)-6-(4-(((5-(4-chlorophenyl)pyrazolo[1,5-a]pyrimidin-7-yl)oxy)methyl)-1H-1,2,3-triazol-1-yl)tetrahydro-2H-pyran-3,4,5-triyl triacetate emerges as a standout with better anticancer activity against MDA-MB231 cells (IC50 = 29.1 µM), while (2R,3R,4S,5R,6R)-2-(acetoxymethyl)-6-(4-(((5-(4-chlorophenyl)pyrazolo[1,5-a]pyrimidin-7-yl)oxy)methyl)-1H-1,2,3-triazol-1-yl)tetrahydro-2H-pyran-3,4,5-triyl triacetate demonstrates the best inhibitory effects against MCF-7 cells (IC50 = 15.3 µM) in all derived compounds. These results align with our docking analysis and structure–activity relationship (SAR) investigations, further validating the in-vitro outcomes. This work not only underscores the synthetic utility of our devised protocol but also highlights the promising potential of these glycohybrids as candidates for further anticancer therapeutic exploration.

Thiazolo-pyridopyrimidines: An in silico evaluation as a lead for CDK4/6 inhibition, synthesis and cytotoxicity screening against breast cancer cell lines.

Pyridopyrimidines belong to a class of compounds characterized by the presence of nitrogen as heteroatoms. These compounds exhibit diverse biological effects, particularly showing promise as anticancer agents, including actions that inhibit CDK4/6. We designed and synthesized a range of substituted thiazolo-pyridopyrimidines (4a-p). Computational ADME/T analysis and molecular docking were performed using the crystal structure of CDK4/6. Subsequently, we synthesized the top-scoring compounds, characterized them using IR, NMR, and Mass spectroscopy, and assessed their impact on MCF-7 and MDAMB-231 cell lines using the SRB assay. To further evaluate stability, molecular dynamics simulations were conducted for the two most promising compounds within the binding site. The docking scores indicated stronger interactions for compounds 4a, 4c, 4d, and 4g. As a result, these specific compounds (4a, 4c, 4d, and 4g) were chosen for synthesis and subsequent screening to assess their cytotoxic effects. Remarkably, compounds 4c and 4a exhibited the most promising activity in terms of their IC50 values across both tested cell lines. Furthermore, molecular dynamics simulation studies uncovered an elevated level of stability within the 4c-6OQO complex. By integrating insights from computational, in vitro, and molecular dynamics simulation findings, compound 4c emerges as a leading candidate for future investigations. The presence of a polar hydroxyl group at the C2 position of the 8-phenyl substitution on the pyridopyrimidine rings appears to contribute to the heightened activity of the compound. Further enhancements to cytotoxic potential could be achieved through structural refinements.

Synthesis of triazole bridged N-glycosides of pyrazolo[1,5-a]pyrimidinones as anticancer agents and their in silico docking studies.

In the pursuit of novel therapeutic agents, we present a comprehensive study on the design, synthesis, and evaluation of a diverse library of triazole bridged N-glycosides of pyrazolo[1,5-a]pyrimidinones, employing a microwave-assisted synthetic approach via 'click chemistry'. This methodology offers efficient and accelerated access to the glycohybrids, showcasing improved reaction conditions that yield high-quality products. In this research endeavor, we have successfully synthesized a series of twenty-seven triazole bridged N-glycosides of pyrazolo[1,5-a]pyrimidinones. Our investigation extends beyond synthetic endeavors to explore the potential therapeutic relevance of these compounds. We subjected them to rigorous in vitro screening against prominent breast cancer cell lines MCF-7, MDA-MB231, and MDA-MB453. Among the library of compounds synthesized, (2S,3S,4R,5S,6S)-2-(acetoxymethyl)-6-(4-((5-(4-methoxyphenyl)-7-oxopyrazolo[1,5-a]pyrimidin-1(7H)-yl)methyl)-1H-1,2,3-triazol-1-yl)tetrahydro-2H-pyran-3,4,5-triyl triacetate emerged as a potent compound, exhibiting remarkable anti-cancer activity with an IC50 value of 27.66 μM against the MDA-MB231 cell line. Additionally, (2S,3R,4R,5S,6S)-2-(acetoxymethyl)-6-(4-((7-oxo-5-(4-(trifluoromethyl)phenyl)pyrazolo[1,5-a]pyrimidin-1(7H)-yl)methyl)-1H-1,2,3-triazol-1-yl)tetrahydro-2H-pyran-3,4,5-triyl triacetate displayed notable inhibitory potential against the MCF-7 cell line, with an IC50 value of 4.93 μM. Furthermore, in silico docking analysis was performed to validate our experimental findings. These findings underscore the promise of our triazole bridged N-glycosides of pyrazolo[1,5-a]pyrimidinones as potential anti-cancer agents. This research not only enriches the field of glycohybrid synthesis but also contributes valuable insights into the development of novel anti-cancer therapeutics.

Synthesis and characterization of novel uranyl clusters supported by bis(pyrazolyl) methane ligands: biomimetic catalytic oxidation, BSA protein interaction and cytotoxicity studies.

Two novel uranyl complexes were synthesized using bis-pyrazolyl methane ligands. The complexes were characterized by several spectroscopic techniques, including UV-Vis, IR, NMR, mass spectrometry, fluorescence, electrochemical, and thermogravimetric analysis. The solid-state structure of the complex C1 was determined with the help of single-crystal X-ray diffraction studies. The complexes C1 and C2 efficiently catalyse the oxidation of 3,5-di-tert-butyl catechol and 2-aminophenol in the atmospheric air, imitating the catalytic activity of the catechol oxidase and phenoxazinone synthase enzymes. The kinetic parameters and the catalytic efficiency (K cat/K M) of the reactions were calculated. Formation of organic free radicals in the catalytic reactions was confirmed by EPR spectroscopy. The interaction of these complexes with the protein, bovine serum albumin, was investigated by using UV-Vis and fluorescence spectral analysis. The cytotoxicity of the complexes against MDAMB-231 and A549 cell lines was investigated, and IC50 values were determined.

Preliminary anticancer evaluation of new Pd(II) complexes bearing NNO donor ligands

In this study we presented a novel series of NNO tridentate ligands generating imino, amido and oxo donor pocket for Pd(II) coordination. All the compounds were meticulously characterized by elemental analysis and advanced spectroscopic techniques, including FTIR, proton and carbon NMR. The synthesized compounds underwent rigorous evaluation for their potential as anti-cancer agents, utilizing the aggressive breast cancer cell lines MDA-MB (ATCC) and MCF-7 as a crucial model for assessing growth inhibition in cancer cells. Remarkably, the MTT assay unveiled the robust anti-cancer activity for all palladium complexes against MDA-MB-231 and MCF-7 cells. Particularly, complex [Pd(L1)(CH3CN)] exhibited exceptional potency with an IC50 value of 25.50 ± 0.30 µM (MDA-MB-231) and 20.76 ± 0.30 µM (MCF-7), compared to respective 27.00 ± 0.80 µM and 24.10 ± 0.80 µM for cisplatin, underscoring its promising therapeutic potential. Furthermore, to elucidate the mechanistic basis for the anti-cancer effects, molecular docking studies on tyrosine kinases, an integral target in cancer research, were carried out. The outcome of these investigations further substantiated the remarkable anticancer properties inherent to these innovative compounds. This research offers a compelling perspective on the development of potent anti-cancer agents rooted in the synergy between ligands and Pd(II) complexes and presenting a promising avenue for future cancer therapy endeavors.

Pseudoceranoids A-J, Sesquiterpene-Based Meroterpenoids with Cytotoxicity from the Sponge Pseudoceratina purpurea.

Pseudoceranoid A (1), a rare merosesquiterpene featuring a rearranged 4,9-friedodrimane-type core with a crotonolactone moiety, two new rearranged 4,9-friedodrimane-type sesquiterpene cyclopentanones (2 and 3), and three new rearranged 4,9-friedodrimane-type sesquiterpene hydroquinones (4-6), along with two new drimane-type sesquiterpene derivatives (7 and 8), as well as two new 4,9-friedodrimane-type sesquiterpene quinones (9 and 10), were isolated from the South China Sea sponge Pseudoceratina purpurea. The structures of compounds were established by analysis of spectroscopic data, as well as by single-crystal X-ray diffraction, DP4+ probability analyses, and calculated electronic circular dichroism. Compound 4 showed weak cytotoxicity against K562, H69AR, and MDAMB-231 cell lines with IC50 values of 3.01, 7.74, and 9.82 μM, respectively. Compound 5 exhibited cytotoxicity against the H69AR cell line with an IC50 value of 2.85 μM.

Abstract A104: ADAR1-associated metabolic vulnerabilities in triple-negative breast cancer

Abstract Triple-negative breast cancer (TNBC), lacking expression of estrogen, progesterone, and HER2 receptors, is aggressive and lacks targeted treatment options. Therefore, the mission to identify actionable targets remains the top priority. We recently demonstrated that an RNA editing enzyme, adenosine deaminase acting on RNA 1 (ADAR1), plays important roles in TNBC’s ability to initiate and maintain tumorigenesis. We posit that ADAR1 functions as a homeostatic factor protecting TNBC from stresses when otherwise kept in check, contributing to tumorigenesis. By both targeted and unbiased approaches, we identified two metabolic vulnerabilities, 1) iron-dependent cell death pathway, ferroptosis, and 2) serine addiction, associated with ADAR1 in TNBC. By performing single-reaction monitoring-based liquid chromatography coupled to mass spectrometry (LC-MS) to measure intracellular lipid contents, we showed that ADAR1 loss in TNBC cells increased the abundance of polyunsaturated fatty acid phospholipids (PUFA-PL), of which peroxidation is the primary driver of ferroptosis. Transcriptomic analysis and phenotypic drug screen using a ferroptosis-focused library were performed to identify underlying mechanisms and drug candidates synergizing with ADAR1 loss through ferroptosis, respectively. Meanwhile, an unbiased screen using a FDA-approved compound library revealed that ADAR1 loss also sensitizes TNBC cell line MDA-MB231 to inhibition of the serine biosynthesis pathway. We showed that ADAR1 knockdown leads to altered serine transport, and a metabolic flux analysis using labeled (U-13C) glucose will be performed to determine if ADAR1 loss affects de novo serine biosynthesis and one-carbon metabolism. By testing the hypothesis that ADAR1 regulates the metabolic fitness of TNBC by desensitizing ferroptosis and serine addiction, we aim to leverage these metabolic vulnerabilities to inform basic, pre-clinical, and clinical studies to develop novel therapeutic strategies for TNBC. Citation Format: Che-Pei Kung, Leah P Shriver, Nick Terzich, Ma Xenia G Ilagen, Mike Prinsen, Sua Ryu, Raleigh D Kladney, Gary J Patti, Leonard B Maggi, Jason D Weber. ADAR1-associated metabolic vulnerabilities in triple-negative breast cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr A104.

In Vitro Cytotoxicity Efficiency of Extracellular L-Glutaminase Produce by Mesophilic Bacteria, Kurthia Gibsonii on Lncap, MDA-MB 231 and Hepg-2 Cell Lines

Mesophilic bacteria from soil habitat have been reported to produce extracellular L-glutaminase. The present study was carried out to anticancer screening of L-glutamiase producing bacteria (Kurthia gibsonii) from soil sample of cattle feeding site from Satara parisar, Chhatrapati Sambhajinagar. Results showed, among three soil samples of cattle feeding farms, Kurthia gibsonii was isolated. From that exhibited the highest L-glutaminase activity. Moreover, the in vitro cytotoxic activity of L-glutaminase against the (Lymph Node Carcinoma of the Prostate) LNCaP, (an epithelial, human breast cancer cell line) MDA-MB 231 and hepatocellular (HepG-2) carcinoma cell lines at different concentration (0.47, 0.94, 1.88, 3.75, 7.50, 15.00, 30.00 and 60.00 μg/ml) by the MTT assay and compared with the standard Doxrubcin. The antitumor effect against human liver carcinoma cell line revealed that L-glutaminase produced by Kurthia gibsonii showed potent cytotoxic activity of tested cell line in a dose-dependent manner with an LC50 value of 4.1 μg/ml.

Green synthesis of Iron oxide and Iron dioxide nanoparticles using Euphorbia tirucalli: characterization and antiproliferative evaluation against three breast cancer cell lines

Researchers have become increasingly interested in nanoparticles made from plants because of their stability and large surface area. In the current study, iron oxide and iron dioxide nanoparticles were synthesized using aerial parts of the E. tirucalli as a reducing agent. The nanoparticles were analyzed using various techniques, including Ultraviolet-visible spectroscopy, Fourier Transform Infrared spectroscopy, X-ray diffractometer, X-ray photoelectron spectroscopy, X-ray energy dispersive spectroscopy, Scanning electron Microscopy, and Transmission Electron Microscopy. The nanoparticles were then investigated for their antiproliferative effect against MCF-7, SK-BR-3, MDA-MB231, and Vero cell lines. The results confirmed the formation of FeO and FeO2 nanoparticles by color change and a UV absorbance peak between 220–390 nm. EDS analysis showed traces of Fe and O, while TEM confirmed the nanoparticle size of 100 nm. FTIR showed a peak at 514 nm. The FeO-RT NPs demonstrated over 80% antiproliferative activity against the MCF-7 cell line at a concentration of 10 μg/mL. while doxorubicin, FeO-RT NPs, and DCM extract showed similar activity against the MDA-MB231 cell line at 10 and 1 g/mL concentrations. However, Vero and SK-BR-3 cell lines showed decreased antiproliferative activity. This study highlights the environmentally friendly use and safe application of iron oxide NPs in cancer therapy.