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Biology subjects

Afzali, F.

Publications and source records attributed to Afzali, F..

7 recordsLinked to original sources

Cell State Chaos Underpins the Evolution of SMARCA4-Deficient Dedifferentiated Endometrial Cancer

Dedifferentiated endometrial carcinoma (DDEC) is a histologically unique cancer type, wherein well-differentiated regions lie adjacent to morphologically distinct, high-grade lesions that are histologically undifferentiated. Previous studies have determined that in nearly half of the cases dedifferentiation is associated with the genomic inactivation of SMARCA4, a catalytic subunit belonging to the SWI/SNF chromatin remodelling complex (SWI/SNF CRC), suggesting that SMARCA4 loss causes dedifferentiation. Herein, using gene editing, we reveal that when serially passaged in mice, SMARCA4-deficient endometrial cancer cells repeatably and predictably generate heterogeneous admixtures of differentiated and undifferentiated cells, resembling human DDEC. Surprisingly, despite this metamorphosis, SMARCA4 loss does not induce lineage plasticity nor reprogramming to a less differentiated fate. Rather, single-cell sequencing combined with barcoding demonstrated that SMARCA4 loss induces a dysregulated epigenome that allows cells to randomly move through cellular states that are otherwise shared with SMARCA4-expressing well-differentiated cancer cells. This finding was validated using a cohort of patient samples, such that epithelial fate markers (E-CADHERIN) can be detected in morphologically undifferentiated cells. Collectively, this work constitutes the first repeatable model of human dedifferentiated cancer and suggests that histological dedifferentiation is not due to the acquisition of a stem cell-like fate. Rather, undifferentiated tissue emerges due to epigenomic dysfunction concomitant with the arbitrary movement of cancer cells between cellular states.

cancer biology↗

Isolation of Extracellular Vesicles from Minimal Volume Ascites Fluid Using Strong Anion Exchange Magnetic Beads

Ovarian cancer (OC) remains a leading cause of gynecologic cancer mortality due to late-stage diagnosis and limited early detection strategies. Ascites fluid, a pathological hallmark of OC, is a rich source of tumor-derived extracellular vesicles (EVs) that reflect the tumor microenvironment and hold promise for biomarker discovery. However, isolating EVs from minimal ascites volumes (<100 {micro}L) poses technical challenges using conventional methods like ultracentrifugation or size-exclusion chromatography (SEC). This study explores the application of strong anion exchange (SAX) magnetic beads (Mag-Net) for efficient EV isolation from as little as 2 {micro}L of ascites fluid from both murine models and a human patient with mucinous borderline tumor. We demonstrate that SAX achieves robust EV capture at 10{micro}l of input volume, enabling comprehensive proteomic profiling and single-EV surface-enhanced Raman spectroscopy (SERS) with a >2-fold increase in proteomic depth compared to raw ascites. Notably, this study was able to identify 1000 proteins not previously annotated in Vesiclepedia for OC-derived EVs, alongside distinct SERS signatures, highlighting the potential for multiomic analysis. Comparative analysis with UC revealed enhanced proteomic depth obtained with SAX beads, albeit we also observed differential detection of canonical markers (e.g., CD9, CD81) between input volumes of ascites fluid. These findings establish SAX as a scalable, low-input platform for EV-based biomarker discovery, paving the way for improved early detection and molecular insights into OC progression.

biochemistry↗

Reduction in ETFDH expression optimizes cancer cell bioenergetics

Mitochondrial electron transport flavoprotein (ETF) insufficiency causes metabolic diseases known as a multiple acyl-CoA dehydrogenase deficiency (MADD). In contrast to muscle, ETFDH is a non-essential gene in acute lymphoblastic leukemia NALM-6 cells, and its expression is reduced across human cancers. ETF insufficiency caused by decreased ETFDH expression limits flexibility of OXPHOS fuel utilization but paradoxically increases cancer cell bioenergetics and accelerates neoplastic growth by activation of the mTORC1/BCL-6/4E-BP1 axis. Collectively, these findings reveal that while ETF insufficiency is rare and has detrimental effects in non-malignant tissues, it is common in neoplasia, where ETFDH downregulation leads to bioenergetic and signaling reprogramming that accelerate neoplastic growth.

cancer biology↗

MTOR modulation induces selective perturbations in histone methylation which influence the anti-proliferative effects of mTOR inhibitors

Emerging data suggest a significant cross-talk between metabolic and epigenetic programs. However, the relationship between the mechanistic target of rapamycin (mTOR) which is a pivotal regulator of cellular metabolism, and epigenetic modifications remains poorly understood. We thus explored the impact of modulating mTOR signaling on histone methylation, a well-known epigenetic modification. Our results showed that mTORC1 activation caused by abrogation of TSC2 increased H3K27me3 but not H3K4me3 or H3K9me3. This appeared to be mediated via the induction of EZH2 protein synthesis, downstream of 4EBPs. Surprisingly, mTOR inhibition also induced H3K27me3 independently of TSC2. This coincided with reduced EZH2 and increased EZH1 protein levels. Notably, the ability of mTOR inhibitors to induce H3K27me3 levels was positively correlated with their anti-proliferative effects. Collectively, our findings demonstrate that both activation and inhibition of mTOR selectively increase H3K27me3 by distinct mechanisms, whereby the ability of mTOR inhibitors to induce H3K27me3 influences their anti-proliferative effects. HighlightsO_LIParadoxically, both mTOR activation and inhibition induce H3K27me3. C_LIO_LIThe effect of mTOR inhibitors on H3K27me3 are not secondary to cell cycle arrest. C_LIO_LIH3K27me3 triggered by mTOR suppression coincides with perturbations in EZH1/2 ratio. C_LIO_LIH3K27me3 impacts on the anti-proliferative effects of mTOR inhibitors. C_LI

molecular biology↗

Designing a novel multi-epitope T vaccine for targeting protein for Xklp-2 (TPX2) in hepatocellular carcinoma based on immunoinformatics approach

Hepatocellular carcinoma (HCC) is one of the leading cancer-related deaths worldwide. Recently, studies for HCC treatment are focused on cancer immunotherapy, particularly cancer vaccines, to complete and assist other therapies. TPX2 is a microtubule-associated protein necessary for cell division; therefore, alteration in its expression, especially up regulation, is associated with several human carcinomas such as HCC.\n\nIn this study, immunoinformatics tools were used to design a rational multi-epitope T vaccine against TPX2 in HCC. Cytotoxic T lymphocytes (CTL) and Helper T lymphocytes (HTL) epitopes were predicted and Maltose-binding protein (MBP) was added to the construct as an adjuvant. Evaluation of vaccine properties was indicated that our construct is stable and immunogenic enough to induce relevant responses besides not being allergic. After predicting the tertiary structure and energy minimization, protein-protein docking was performed to calculate the free energy of possible interactions between the vaccine and toll-like receptor 4 (TLR4) to assure that simultaneous complementary responses would be activated by our construct. Finally, Codon optimization and in-silico cloning were performed to ensure the vaccine expression efficiency in the desired host.

bioinformatics↗

Unearthing Regulatory Axes of Breast Cancer circRNAs Networks to Find Novel Targets and Fathom Pivotal Mechanisms

Circular RNAs (circRNAs) along other complementary regulatory elements in ceRNAs networks possess valuable characteristics for both diagnosis and treatment of several human cancers including breast cancer (BC). In this study, we combined several systems biology tools and approaches to identify influential BC circRNAs, RNA binding proteins (RBPs), miRNAs, and related mRNAs to study and decipher the BC triggering biological processes and pathways.\n\nRooting from the identified total of 25 co-differentially expressed circRNAs (DECs) between triple negative (TN) and luminal A subtypes of BC from microarray analysis, five hub DECs (hsa_circ_0003227, hsa_circ_0001955, hsa_circ_0020080, hsa_circ_0001666, and hsa_circ_0065173) and top eleven RBPs (AGO1, AGO2, EIF4A3, FMRP, HuR (ELAVL1), IGF2BP1, IGF2BP2, IGF2BP3, EWSR1, FUS, and PTB) were explored to form the upper stream regulatory elements. All the hub circRNAs were regarded as super sponge having multiple miRNA response elements (MREs) for numerous miRNAs. Then four leading miRNAs (hsa-miR-149, hsa-miR-182, hsa-miR-383, and hsa-miR-873) accountable for BC progression were also introduced from merging several ceRNAs networks. The predicted 7- and 8-mer MREs matches between hub circRNAs and leading miRNAs ensured their enduring regulatory capability. The mined downstream mRNAs of the circRNAs-miRNAs network then were presented to STRING database to form the PPI network and deciphering the issue from another point of view. The BC interconnected enriched pathways and processes guarantee the merits of the ceRNAs networks members as targetable therapeutic elements.\n\nThis study suggested extensive panels of novel covering therapeutic targets that are in charge of BC progression in every aspect, hence their impressive role cannot be excluded and needs deeper empirical laboratory designs.

bioinformatics↗

Molecular Correlations between Breast Cancer and Diabetes Mellitus Type 2 Examined by In Silico analyses and Drug Inhibitory Effects

Nearly 16% of people with breast cancer (BC) have Diabetes Mellitus type 2 (DM2) and are at a higher risk of death worldwide. Their common regulatory factors and functional mechanisms can be targeted applying multi-target drugs including Metformin (MTFN) and Curcumin (CURC). In this study, we used in-silico approaches to study the potential underlying mechanisms of this co-treatment strategy on BC and DM2 in order to introduce novel therapeutic targets.\n\nThe total number of 48 shared differentially expressed genes (17 up-regulated and 31 down-regulated) were identified through establishing diseases protein-protein network and BC RNA-sequencing expression data. The integration of functional clustering and pathway analyses revealed that the most involved cellular pathways and processes are regard to cells proliferation, death, migration, and response to external stimulus. Afterwards, the MTFN/CURC correlation and co-treatment optimization was probed through response surface methodology (RSM) based on MCF7 cell line and confirmed by MDA-MB-231. Combination index calculation by MTT viability assay proved supportive effects on both cell lines. The superior apoptotic potential of co-treatment compared to single treatments was shown on inhibition of MCF7 proliferation and induction of cell death demonstrated by cell body co-staining and flow cytometry as well as gene expression analysis via RT-PCR. Furthermore, wound-healing scratch assay showed that this co-treatment has a slightly higher effect on migration inhibition compared to single treatments.\n\nIn conclusion, our study used in-silico and in-vitro approaches and introduced a potential regulatory panel between BC and DM2. We also provided a linear model and equation that show the positive relation of drugs co-treatment. The proposed co-treatment strategy successfully controlled the biological processes under investigation.

cancer biology↗