The remodelling of actin composition as a hallmark of cancer

Thiazole-fused androstenone and ethisterone derivatives: potent β- and γ-actin cytoskeleton inhibitors to treat melanoma tumors

Melanoma, the most fatal form of skin cancer, often becomes resistant to the current therapeutic approaches in most patients. To explore new treatment options, fused thiazole derivatives were synthesized, and several of these compounds demonstrated potent anti-melanoma activity both in vitro and in vivo. These compounds exhibited significant cytotoxicity against melanoma cell lines at low concentrations. The lead molecules induced apoptosis and caused G2/M phase cell cycle arrest to a lesser extent. These compounds also displayed remarkable antimetastatic activities in several cell-based and molecular assays, significantly inhibiting key processes of metastasis, such as cell migration and adhesion. mRNA sequencing revealed significant downregulation of β-actin (ACTB) and γ-actin (ACTG1) at the transcriptional level, and a similar effect was observed at the protein level by western immunoblotting and proteomics assays. Actin-rich membrane protrusions formation is crucial for facilitating metastasis by promoting cell migration. Fluorescence microscopy demonstrated that compounds E28 and E47 inhibited the formation of these membrane protrusions and impaired actin cytoskeleton dynamics. Docking studies suggested the lead compounds may suppress tumor proliferation and metastasis by targeting the mechanistic target of Rapamycin complex 2 (mTORC2). All these findings unanimously indicated the translational perspective of ethisterone and androstenone fused thiazole derivatives as potent antimetastatic and antimelanoma agents. In a preclinical mouse melanoma model, compounds E2 and E47 significantly reduced tumor growth and greatly improved overall mice survival, while showing a favorable safety profile based on a comprehensive blood plasma metabolite profile. These lead molecules also displayed promising physicochemical properties, making them strong candidates for further drug development studies.

Proteomic Profiling of Pre- and Post-Surgery Saliva of Glioblastoma Patients: A Pilot Investigation

Glioblastoma multiforme (GBM) is an extremely aggressive brain tumor characterized by a high infiltration capability and recurrence rate. Early diagnosis is crucial to improve the prognosis and to personalize the therapeutic approach. This research explored, by LC-MS proteomic analysis after proteolytic digestion, the molecular profile of pre- and post-operative saliva pools from newly diagnosed (ND) GBM patients by comparing different times of collection and tumor recurrence (R). CYCS, PRDX2, RAB1C, PSMB1, KLK6, TMOD3, PAI2, PLBD1, CAST, and AHNAK, all involved in processes of tumor invasiveness and chemo- and radio-resistance, were found to depict the pre-surgery saliva of both ND and R GBM. PADI4 and CRYAB proteins, identified among the most abundant proteins exclusive of ND GBM pre-surgery saliva and classified as proteins elevated in glioma, could have a potential role as disease biomarkers. Selected panels of S100 proteins were found to potentially differentiate ND from R GBM patient saliva. TPD52 and IGKV3, exclusively identified in R GBM saliva, could be additionally distinctive of tumor relapse. Among the proteins identified in all pools, label-free relative quantitation showed statistically significant different levels of TXN, SERPINB5, FABP5, and S100A11 proteins between the pools. All of these proteins showed higher levels in both ND_ and R_T0 pre-surgery saliva with respect to CTRL and different modulation after surgery or chemo-radiotherapy combined treatment, suggesting a role as a potential panel of GBM predictive and prognostic biomarkers. These results highlight and confirm that saliva, a biofluid featured for an easily accessible and low invasiveness collection, is a promising source of GBM biomarkers, showing new potential opportunities for the development of targeted therapies and diagnostic tools.

Heterogeneity of the Alpha-Smooth Muscle Actin Tumor Score in Breast Cancer Cells Significantly Affects Tumor Invasiveness, Recurrence, and Patient Survival

BACKGROUND

Alpha-smooth muscle actin (αSMA) has been widely investigated in malignancies, primarily concerning its expression in cancer-associated fibroblasts (CAFs) inside the tumor stroma. Microscopic examination indicates that αSMA expression is not confined to the tumor stromal compartment but is also present in a subset of tumor cells, and this expression correlates with an enhanced invasive phenotype of malignant cells from lung, liver, or ovarian malignancies. Information on actin expression in breast cancer (BC) cells is scarce, and its influence on clinicopathological characteristics remains ambiguous due to conflicting findings in the literature.

OBJECTIVE

To examine the αSMA tumor score in breast cancer cells utilizing digital image analysis (DIA) methodologies and to critically analyze the varying effects of αSMA tumor score values on clinicopathologic parameters, particularly focusing on tumor cell invasiveness, recurrence, and survival.

MATERIALS AND METHODS

Double immunostaining for CD34 and αSMA was conducted on 53 breast cancer cases that were thoroughly characterized in relation to clinicopathologic data. Double immunostaining for CD34 and αSMA demonstrated different distribution patterns of both markers in normal and breast cancer tissues. DIA data about αSMA tumor cell density, intensity, tumor score, and histological score were correlated with clinicopathological factors.

RESULTS

We delineated three unique breast cancer subgroups based on αSMA tumor scores: a 9.43% low-expressing subgroup (αSMA_TSlow, score 4), a 35.07% medium-expressing subgroup (αSMA_TSmed, scores 5 and 6), and a 55.5% high-expressing subgroup (αSMA_TShigh, scores 7 and 8). Stromal immature vessels and tertiary lymphoid structures (TLS) exhibited a strong correlation with αSMA_TSlow, whereas recurrence, perineural, and lymphovascular invasion strongly influenced the αSMA_TSmed and αSMA_TShigh subgroups. The αSMA_TSmed subgroup demonstrated the most heterogeneity with the influence of αSMA-expressing breast cancer cells on tumor size, nodal status, perineural and lymphovascular invasion, menopausal status, recurrence, and survival. Most of the cases from the αSMA_TSlow subgroup had Luminal B and Luminal B-HER2 phenotypes, while triple-negative breast cancer (TNBC) represented one-third of all cases in the αSMA_TShigh subgroup.

CONCLUSION

αSMA-expressing breast cancer cells variably affect malignant growth, invasion, and recurrence, highly contingent upon their density and expression intensity. The current investigation identified an αSMA_TSmed BC subgroup that appears to promote invasiveness, recurrence, and survival in breast cancer. Our data indicate that αSMA BC-expressing cells play a dual role in BC progression, contingent upon their percentage and expression intensity; however, further research is required to elucidate the factors and mechanisms responsible for their accumulation and/or transdifferentiation in malignant breast tissue.

Bisphenol A disrupts the neuronal F-actin cytoskeleton by activating the RhoA/ROCK/LIMK pathway in Neuro-2a cells

Bisphenol A (BPA) is an environmental endocrine disruptor that is widely present in the environment and has been reported to affect neuronal cytoskeleton and neural function. However, the exact molecular mechanisms remain unclear. In the present study, the effects of BPA on cytoskeleton rearrangement were examined, and the associated signaling pathways, which were influenced by the RhoA/ROCK/LIMK pathway in Neuro-2a cells in vitro, were identified. Specifically, Neuro-2a cells were exposed to BPA, and the effects of BPA exposure on the cytoskeleton of neuronal cells and on the activation or nonactivation of the RhoA/ROCK signaling pathway were evaluated using Cell Counting Kit-8 (CCK8), phalloidin staining, western blot, and real-time PCR. A RhoA inhibitor (Rhosin hydrochloride) and a ROCK inhibitor (Y-27632) were then used to elucidate the precise function of the pathway. The results demonstrated that 50-100 μM BPA exposure inhibited Neuro-2a cell viability and caused the formation of aberrantly polymerized F-actin and stress fibers. In addition, the RhoA/ROCK pathway was activated, and the expression levels of the pathway-related molecules-RhoA, ROCK2, LIMK1, Cofilin, Profilin, p-MLC2, and F-actin were dramatically elevated. The addition of Rhosin and Y-27632 resulted in a decrease in F-actin polymerization in the Neuro-2a cells, the disassembly of stress fibers, and a noteworthy drop in the levels of molecular proteins related to the RhoA/ROCK pathway affected by BPA. Together, these new findings indicated that BPA exposure thus activated the RhoA/ROCK signaling pathway and caused an abnormal accumulation of F-actin in the Neuro-2a cells, in turn altering the microfilament cytoskeleton. F-actin was restored when the RhoA/ROCK pathway was inhibited, suggesting that the process of BPA-induced neuronal cytoskeletal degradation is linked to the RhoA/ROCK signaling cascade.

Upregulation of miRNA-450b-5p targets ACTB to affect drug resistance and prognosis of ovarian cancer via the PI3K/Akt signaling pathway

Background

Ovarian cancer (OC) is the most malignant gynecologic cancer, and chemoresistance is a major cause of treatment failure in patients with OC. The understanding of microRNA (miRNA) in cancer is limited, and the role of miRNA (miR)-450b-5p in cancer drug resistance is unknown. In this study, we aim to evaluate the role of miR-450b-5p in drug-resistant OC and its underlying mechanisms.

Methods

MiR-450b-5p expression was assessed in drug-sensitive and resistant OC cells via quantitative real-time polymerase chain reaction. Cell viability was evaluated using the Cell Counting Kit-8 assay. Progression-free survival (PFS) and overall survival (OS) curves were generated using the Kaplan-Meier method and the log-rank test. Target genes of miR-450b-5p were identified from the Cancer MIRNome database. Co-expressed genes were obtained from The Cancer Genome Atlas and Cancer Genome cBioportal for pathway enrichment and functional clustering analysis.

Results

The miRNA-450b-5p expression was significantly increased in A2780 and SKOV3 OC-resistant cells and significantly increased by 17-fold in the A2780-CBP-Lv-miR-450b-5p cells compared to A2780-CBP and A2780-CBP-Lv-NC cells. The up-regulated expression of miR-450b-5p increased the cell viability and half maximal inhibitory concentration (IC50) of A2780 platinum-resistant cells and was associated with poor OS. We obtained 33 potential target genes of miR-450b-5p and beta-actin (ACTB) might be a potential target of miR-450b-5p. Low expression of ACTB predicted poor OS and PFS. We obtained 362 common genes co-expressed with ACTB, which involved 4 critical pathways. PI3K acted as an upstream pathway of the other three pathways, which ultimately responded to drug resistance regulation in OC. The genes enriched in four pathways were cross-analyzed and 13 overlapping genes were obtained. These 13 genes were also significantly and positively co-expressed with ACTB at both protein and mRNA levels.

Conclusions

High expression of miRNA-450b-5p might affect drug resistance and prognosis in OC by targeting 13 co-expressed genes of ACTB directly through the PI3K/Akt signaling pathway. Thus, miR-450b-5p might provide a new therapeutic target for drug resistance in OC.

Filamentous Actin in the Nucleus in Triple-Negative Breast Cancer Stem Cells: A Key to Drug-Induced Nucleolar Stress and Stemness Inhibition?

Actin, primarily a cytoplasmic cytoskeleton protein, is transported in and out of the nucleus with the help of actin-binding proteins (ABPs). Actin exists in two forms, i.e., monomeric globular (G-actin) and polymerized filamentous (F-actin). While G-actin promotes gene transcription by associating with RNA polymerases, F-actin can inhibit this effect in the nucleus. Unexpectedly, we found that lovastatin, an FDA-approved lipid-lowering drug, induces actin redistribution and its translocation into the nucleus in triple-negative breast cancer (TNBC) cancer stem cells. Lovastatin treatment also decreased levels of rRNAs and stemness markers, which are transcription products of RNA Pol I and Pol II, respectively. Bioinformatics analysis showed that actin genes were positively correlated with ABP genes involved in the translocation/polymerization and transcriptional regulation of nuclear actin in breast cancer. Similar correlations were found between actin genes and RNA Pol I genes and stemness-related genes. We propose a model to explain the roles of lovastatin in inducing nucleolar stress and inhibiting stemness in TNBC cancer stem cells. In our model, lovastatin induces translocation/accumulation of F-actin in the nucleus/nucleolus, which, in turn, induces nucleolar stress and stemness inhibition by suppressing the synthesis of rRNAs and decreasing the expression of stemness-related genes. Our model has opened up a new field of research on the roles of nuclear actin in cancer biology, offering potential therapeutic targets for the treatment of TNBC.

Detection of neoplastic-immune hybrid cells with metastatic properties in uveal melanoma

BACKGROUND

Uveal melanoma is the most common non-cutaneous melanoma and is an intraocular malignancy affecting nearly 7,000 individuals per year worldwide. Of these, approximately 50% will progress to metastatic disease for which there are currently no effective curative therapies. Despite advances in molecular profiling and metastatic stratification of uveal melanoma tumors, little is known regarding their underlying biology of metastasis. Our group has identified a disseminated neoplastic cell population characterized by co-expression of immune and melanoma proteins, circulating hybrid cells (hybrids), in patients with uveal melanoma. Compared to circulating tumor cells, which lack expression of immune proteins, hybrids are detected at an increased prevalence in peripheral blood and can be used as a non-invasive biomarker to predict metastatic progression.

METHODS

To ascertain mechanisms underlying enhanced hybrid cell dissemination we identified hybrid cells within primary uveal melanoma tumors using single cell RNA sequencing (n = 8) and evaluated their gene expression and predicted ligand-receptor interactions in relation to other melanoma and immune cells within the primary tumor. We then verified expression of upregulated hybrid pathways within patient-matched tumor and peripheral blood hybrids (n = 4) using cyclic immunofluorescence and quantified their protein expression relative to other non-hybrid tumor and disseminated tumor cells.

RESULTS

Among the top upregulated genes and pathways in hybrid cells were those involved in enhanced cell motility and cytoskeletal rearrangement, immune evasion, and altered cellular metabolism. In patient-matched tumor and peripheral blood, we verified gene expression by examining concordant protein expression for each pathway category: TMSB10 (cell motility), CD74 (immune evasion) and GPX1 (metabolism). Both TMSB10 and GPX1 were expressed on significantly higher numbers of disseminated hybrid cells compared to circulating tumor cells, and CD74 and GPX1 were expressed on more disseminated hybrids than tumor-resident hybrids. Lastly, we identified that hybrid cells express ligand-receptor signaling pathways implicated in promoting metastasis including GAS6-AXL, CXCL12-CXCR4, LGALS9-P4HB and IGF1-IGFR1.

CONCLUSION

These findings highlight the importance of TMSB10, GPX1 and CD74 for successful hybrid cell dissemination and survival in circulation. Our results contribute to the understanding of uveal melanoma tumor progression and interactions between tumor cells and immune cells in the tumor microenvironment that may promote metastasis.

Role of WAVE3 as an of actin binding protein in the pathology of triple negative breast cancer

Breast cancer, a prevalent global health concern, has sparked extensive research efforts, particularly focusing on triple negative breast cancer (TNBC), a subtype lacking estrogen receptor (ER), progesterone receptor, and epidermal growth factor receptor. TNBC's aggressive nature and resistance to hormone-based therapies heightens the risk of tumor progression and recurrence. Actin-binding proteins, specifically WAVE3 from the Wiskott-Aldrich syndrome protein (WASP) family, have emerged as major drivers in understanding TNBC biology. This review delves into the intricate molecular makeup of TNBC, shedding light on actin's fundamental role in cellular processes. Actin, a structural element in the cytoskeleton, regulates various cellular pathways essential for homeostasis. Its dynamic nature enables functions such as cell migration, motility, intracellular transport, cell division, and signal transduction. Actin-binding proteins, including WAVE3, play pivotal roles in these processes. WAVE3, a member of the WASP family, remains the focus of this review due to its potential involvement in TNBC progression. While actin-binding proteins are studied for their roles in healthy cellular cycles, their significance in TNBC remains underexplored. This review aims to discuss WAVE3's impact on TNBC, exploring its molecular makeup, functions, and significance in tumor progression. The intricate structure of WAVE3, featuring elements like the verprolin-cofilin-acidic domain and regulatory elements, plays a crucial role in regulating actin dynamics. Dysregulation of WAVE3 in TNBC has been linked to enhanced cell migration, invasion, extracellular matrix remodeling, epithelial-mesenchymal transition, tumor proliferation, and therapeutic resistance. Understanding the role of actin-binding proteins in cancer biology has potential clinical implications, making them potential prognostic biomarkers and promising therapeutic targets. The review emphasizes the need for further research into actin-binding proteins' clinical applications, diagnostic value, and therapeutic interventions. In conclusion, this comprehensive review explores the complex interplay between actin and actin-binding proteins, with special emphasis on WAVE3, in the context of TNBC. By unraveling the molecular intricacies, structural characteristics, and functional significance, the review paves the way for future research directions, clinical applications, and potential therapeutic strategies in the challenging landscape of TNBC.

Transcriptomic and epigenomic landscapes of muscle growth during the postnatal period of broilers

BACKGROUND

Broilers stand out as one of the fastest-growing livestock globally, making a substantial contribution to animal meat production. However, the molecular and epigenetic mechanisms underlying the rapid growth and development of broiler chickens are still unclear. This study aims to explore muscle development patterns and regulatory networks during the postnatal rapid growth phase of fast-growing broilers. We measured the growth performance of Cornish (CC) and White Plymouth Rock (RR) over a 42-d period. Pectoral muscle samples from both CC and RR were randomly collected at day 21 after hatching (D21) and D42 for RNA-seq and ATAC-seq library construction.

RESULTS

The consistent increase in body weight and pectoral muscle weight across both breeds was observed as they matured, with CC outpacing RR in terms of weight at each stage of development. Differential expression analysis identified 398 and 1,129 genes in the two dimensions of breeds and ages, respectively. A total of 75,149 ATAC-seq peaks were annotated in promoter, exon, intron and intergenic regions, with a higher number of peaks in the promoter and intronic regions. The age-biased genes and breed-biased genes of RNA-seq were combined with the ATAC-seq data for subsequent analysis. The results spotlighted the upregulation of ACTC1 and FDPS at D21, which were primarily associated with muscle structure development by gene cluster enrichment. Additionally, a noteworthy upregulation of MUSTN1, FOS and TGFB3 was spotted in broiler chickens at D42, which were involved in cell differentiation and muscle regeneration after injury, suggesting a regulatory role of muscle growth and repair.

CONCLUSIONS

This work provided a regulatory network of postnatal broiler chickens and revealed ACTC1 and MUSTN1 as the key responsible for muscle development and regeneration. Our findings highlight that rapid growth in broiler chickens triggers ongoing muscle damage and subsequent regeneration. These findings provide a foundation for future research to investigate the functional aspects of muscle development.

Integrated machine learning algorithms reveal a bone metastasis-related signature of circulating tumor cells in prostate cancer

Bone metastasis is an essential factor affecting the prognosis of prostate cancer (PCa), and circulating tumor cells (CTCs) are closely related to distant tumor metastasis. Here, the protein-protein interaction (PPI) networks and Cytoscape application were used to identify diagnostic markers for metastatic events in PCa. We screened ten hub genes, eight of which had area under the ROC curve (AUC) values > 0.85. Subsequently, we aim to develop a bone metastasis-related model relying on differentially expressed genes in CTCs for accurate risk stratification. We developed an integrative program based on machine learning algorithm combinations to construct reliable bone metastasis-related genes prognostic index (BMGPI). On the basis of BMGPI, we carefully evaluated the prognostic outcomes, functional status, tumor immune microenvironment, somatic mutation, copy number variation (CNV), response to immunotherapy and drug sensitivity in different subgroups. BMGPI was an independent risk factor for disease-free survival in PCa. The high risk group demonstrated poor survival as well as higher immune scores, higher tumor mutation burden (TMB), more frequent co-occurrence mutation, and worse efficacy of immunotherapy. This study highlights a new prognostic signature, the BMGPI. BMGPI is an independent predictor of prognosis in PCa patients and is closely associated with the immune microenvironment and the efficacy of immunotherapy.

Activating transcription factor 3 is an antitumor gene synergizing with growth differentiation factor 15 to modulate cell growth in human bladder cancer

BACKGROUND

The functions of activating transcription factor 3 (ATF3) within the human bladder remain unexplored. This study delves into the expressions, functions, and regulatory mechanisms of ATF3 in human bladder cancer.

MATERIAL AND METHODS

Gene expressions were determined by immunoblot, RT-qPCR, and reporter assays. Assays of Ki67, colony formation, Matrigel invasion, and the xenograft animal study were used to assess the cell proliferation, invasion, and tumorigenesis in vitro and in vivo. Silico analysis from TCGA database examined the correlations between GDF15 and ATF3 expressions, clinicopathologic features, and progression-free survival rates.

RESULTS

Silico analysis confirmed that ATF3 is an antitumor gene, and the expression positively correlates with GDF15 in bladder cancer tissues. Multivariate analysis revealed that low ATF3/GDF15 but not a single low expression of ATF3 is an independent prognostic factor for progression-free survival of bladder cancer patients. Ectopic overexpression of ATF3 downregulated cell proliferation and invasion in bladder cancer cells in vitro, while ATF3-knockdown reversed these results. Knockdown of ATF3 upregulated EMT markers to enhance cell invasion in vitro and downregulated GDF15, NDRG1, and KAI-1 to elevate tumor growth in vivo. The activation of metformin on ATF3 and GDF15 in bladder cancer cells was blocked by SB431542, a TGFβ receptor inhibitor. ATF3 positively regulated GDF15 expression in bladder cancer cells through a feedback loop.

CONCLUSIONS

Our results identify that ATF3 is a metformin-upregulated antitumor gene. Results of Silico analysis align with cell-based studies suggesting that low ATF3/GDF15 could be a negative prognostic marker for bladder cancer.

Identification and validation of a prognostic signature based on six immune-related genes for colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a prevalent malignancy with high mortality and morbidity rates. Although the significant efficacy of immunotherapy is well established, it is only beneficial for a limited number of individuals with CRC.

METHODS

Differentially expressed immune-related genes (DE-IRGs) were retrieved from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and ImmPort databases. A prognostic signature comprising DE-IRGs was developed using univariate, LASSO, and multivariate Cox regression analyses. A nomogram integrating the independent prognostic factors was also developed. CIBERSORT was used to assess immune cell infiltration (ICI). Furthermore, wound-healing, colony formation, migration, and invasion assays were performed to study the involvement of ACTG1 in CRC.

RESULTS

A signature including six DE-IRGs was developed. The overall survival (OS) rate was accurately estimated for TCGA and GSE38832 cohorts. The risk score (RS) of the signature was an independent factor for OS. Moreover, a nomogram encompassing age, RS, and pathological T stage accurately predicted the long-term OS probability of individuals with CRC. The high-risk group had an elevated proportion of patients treated with ICIs, including native B cells, relative to the low-risk group. Additionally, ACTG1 expression was upregulated, which supported the proliferation, migration, and invasion abilities of CRC cells.

CONCLUSIONS

An immune-related prognostic signature was developed for predicting OS and for determining the immune status of individuals with CRC. The present study provides new insights into accurate immunotherapy for individuals with CRC. Moreover, ACTG1 may serve as a new immune biomarker.

Structural and functional mechanisms of actin isoforms

Actin is a highly conserved and fundamental protein in eukaryotes and participates in a broad spectrum of cellular functions. Cells maintain a conserved ratio of actin isoforms, with muscle and non-muscle actins representing the main actin isoforms in muscle and non-muscle cells, respectively. Actin isoforms have specific and redundant functional roles and display different biochemistries, cellular localization, and interactions with myosins and actin-binding proteins. Understanding the specific roles of actin isoforms from the structural and functional perspective is crucial for elucidating the intricacies of cytoskeletal dynamics and regulation and their implications in health and disease. Here, we review how the structure contributes to the functional mechanisms of actin isoforms with a special emphasis on the questions of how post-translational modifications and disease-linked mutations affect actin isoforms biochemistry, function, and interaction with actin-binding proteins and myosin motors.

Tumor invasiveness is regulated by the concerted function of APC, formins, and Arp2/3 complex

Tumor cell invasion is the initial step in metastasis, the leading cause of death from cancer. Invasion requires protrusive cellular structures that steer the migration of leader cells emanating from the tumor mass toward neighboring tissues. Actin is central to these processes and is therefore the prime target of drugs known as migrastatics. However, the broad effects of general actin inhibitors limit their therapeutic use. Here, we delineate the roles of specific actin nucleators in tuning actin-rich invasive protrusions and pinpoint potential pharmacological targets. We subject colorectal cancer spheroids embedded in collagen matrix-a preclinical model mirroring solid tumor invasiveness-to pharmacologic and/or genetic treatment of specific actin arrays to assess their roles in invasiveness. Our data reveal coordinated yet distinct involvement of actin networks nucleated by adenomatous polyposis coli, formins, and actin-related protein 2/3 complex in the biogenesis and maintenance of invasive protrusions. These findings may open avenues for better targeted therapies.

Toward a Template for Synthetic Actin-Targeting Macrolide Analogues That Inhibit Cancer Cell Invasiveness

Actin barbed end-binding macrolides have been shown to inhibit cancer cell motility and invasion of extracellular matrix (ECM), evoking their potential utility as therapies for metastatic cancers. Unfortunately, the direct use of these compounds in clinical settings is impeded by their limited natural abundance, challenging total synthesis, and detrimental effects on normal tissues. To develop potent analogues of these compounds that are simpler to synthesize and compatible with cell-specific targeting systems, such as antibodies, we designed over 20 analogues of the acyclic side chain (tail) of the macrolide Mycalolide B. These analogues probed the contributions of four distinct regions of the tail towards the inhibition of actin polymerization and ECM invasion by human lung cancer A549 cells. We observed that two of these regions tolerate considerable substituent variability, and we identified a specific combination of substituents that leads to the optimal inhibition of the ECM invasion activity of A549 cells.

TOP1 and R-loops facilitate transcriptional DSBs at hypertranscribed cancer driver genes

DNA double-stranded breaks (DSBs) pose a significant threat to genomic integrity, and their generation during essential cellular processes like transcription remains poorly understood. In this study, we employ several techniques to map DSBs, R-loops, and topoisomerase 1 cleavage complex (TOP1cc) to comprehensively investigate the interplay between transcription, DSBs, topoisomerase 1 (TOP1), and R-loops. Our findings reveal the presence of DSBs at highly expressed genes enriched with TOP1 and R-loops. Remarkably, transcription-associated DSBs at these loci are significantly reduced upon depletion of R-loops and TOP1, uncovering the pivotal roles of TOP1 and R-loops in transcriptional DSB formation. By elucidating the intricate interplay between TOP1cc trapping, R-loops, and DSBs, our study provides insights into the mechanisms underlying transcription-associated genomic instability. Moreover, we establish a link between transcriptional DSBs and early molecular changes driving cancer development, highlighting the distinct etiology and molecular characteristics of driver mutations compared to passenger mutations.

Cytochrome P450 genes expression in human prostate cancer

CYP-dependent metabolites play a critical role in regulating the cell cycle, as well as the proliferative, invasive, and migratory activity of cancer cells. We conducted a study to analyze the relative gene expression of various CYPs (CYP7B1, CYP27A1, CYP39A1, CYP51, CYP1B1, CYP3A5, CYP4F8, CYP5A1, CYP4F2, CYP2J2, CYP2E1, CYP2R1, CYP27B1, CYP24A1) in 41 pairs of prostate samples (tumor and conventional normal tissues) using qPCR. Our analysis determined significant individual variability in the expression levels of all studied CYPs, both in the tumor and in conventionally normal groups. However, when we performed a paired test between the tumor and normal groups, we found no significant difference in the expression of the studied genes. We did observe a tendency to increase the level of CYP1B1 expression in the tumor group. We also did not find any significant difference between the levels of the studied CYPs in the tumor and conventional normal groups at different stages of prostate cancer and pathomorphological indicators. Correlation analysis revealed the presence of a positive relationship between the expressions of some cholesterol-metabolizing CYP genes, as well as between genes responsible for vitamin D biosynthesis and cholesterol biosynthesis. We observed significant correlative relationships between the expression of CYPs and some prostate cancer-related genes (CDH2, MMP9, SCHLAP1, GCR, CYP17A1, ACTA2, CXCL14, FAP, CCL17, MSMB, IRF1, VDR). Therefore, the expression of CYPs is not directly associated with prostate cancer but is largely determined by genetic, epigenetic factors, as well as endogenous substrates and xenobiotics. The significant correlative relationship between CYPs and genes associated with cancer may indicate common regulatory pathways that may have a synergistic effect on the tumor, ensuring the survival of cancer cells.

HIF-1 inhibition reverses opacity in a rat model of galactose-induced cataract

Cataract is an eye disease, in which the lens becomes opaque, causing vision loss and blindness. The detailed mechanism of cataract development has not been characterized, and effective drug therapies remain unavailable. Here, we investigated the effects of Hypoxia-inducible factor 1 (HIF-1) inhibitors using an ex vivo model, in which rat lenses were cultured in galactose-containing medium to induce opacity formation. We found that treatment with the HIF-1 inhibitors 2-Methoxyestradiol (2ME2), YC-1, and Bavachinin decreased lens opacity. Microarray analysis on 2ME2-treated samples, in which opacity was decreased, identified genes upregulated by galactose and downregulated by inhibitor treatment. Subsequent STRING analysis on genes that showed expression change by RT-qPCR identified two clusters. First cluster related to the cytoskeleton and epithelial-mesenchymal transition (EMT). Second cluster related to the oxidative stress, and apoptosis. ACTA2, a known marker for EMT, and TXNIP, a suppressor of cell proliferation and activator of apoptosis, were present in each cluster. Thus, suppression of EMT and apoptosis, as well as activation of cell proliferation, appear to underlie the decrease in lens opacity.

Glutamate is effective in decreasing opacity formed in galactose-induced cataract model

Although cataract is the leading cause of blindness worldwide, the detailed pathogenesis of cataract remains unclear, and clinically useful drug treatments are still lacking. In this study, we examined the effects of glutamate using an ex vivo model in which rat lens is cultured in a galactose-containing medium to induce opacity formation. After inducing lens opacity formation in galactose medium, glutamate was added, and the opacity decreased when the culture was continued. Next, microarray analysis was performed using samples in which the opacity was reduced by glutamate, and genes whose expression increased with galactose culture and decreased with the addition of glutamate were extracted. Subsequently, STRING analysis was performed on a group of genes that showed variation as a result of quantitative measurement of gene expression by RT-qPCR. The results suggest that apoptosis, oxidative stress, endoplasmic reticulum (ER) stress, cell proliferation, epithelial-mesenchymal transition (EMT), cytoskeleton, and histones are involved in the formation and reduction of opacity. Therefore, glutamate may reduce opacity by inhibiting oxidative stress and its downstream functions, and by regulating the cytoskeleton and cell proliferation.

Senescence-related genes analysis in breast cancer reveals the immune microenvironment and implications for immunotherapy

Despite the advent of precision therapy for breast cancer (BRCA) treatment, some individuals are still unable to benefit from it and have poor survival prospects as a result of the disease's high heterogeneity. Cell senescence plays a crucial role in the tumorigenesis, progression, and immune regulation of cancer and has a major impact on the tumor microenvironment. To find new treatment strategies, we aimed to investigate the potential significance of cell senescence in BRCA prognosis and immunotherapy. We created a 9-gene senescence-related signature. We evaluated the predictive power and the role of signatures in the immune microenvironment and infiltration. In vitro tests were used to validate the expression and function of the distinctive critical gene ACTC1. Our risk signature allows BRCA patients to receive a Predictive Risk Signature (PRS), which may be used to further categorize a patient's response to immunotherapy. Compared to conventional clinicopathological characteristics, PRS showed strong predictive efficacy and precise survival prediction. Moreover, PRS subgroups were examined for altered pathways, mutational patterns, and possibly useful medicines. Our research offers suggestions for incorporating senescence-based molecular classification into risk assessment and ICI therapy decision-making.

Tension-induced adhesion mode switching: the interplay between focal adhesions and clathrin-containing adhesion complexes

Integrin-based adhesion complexes are crucial in various cellular processes, including proliferation, differentiation, and motility. While the dynamics of canonical focal adhesion complexes (FAs) have been extensively studied, the regulation and physiological implications of the recently identified clathrin-containing adhesion complexes (CCACs) are still not well understood. In this study, we investigated the spatiotemporal mechanoregulations of FAs and CCACs in a breast cancer model. Employing single-molecule force spectroscopy coupled with live-cell fluorescence microscopy, we discovered that FAs and CCACs are mutually exclusive and inversely regulated complexes. This regulation is orchestrated through the modulation of plasma membrane tension, in combination with distinct modes of actomyosin contractility that can either synergize with or counteract this modulation. Our findings indicate that increased membrane tension promotes the association of CCACs at integrin αVβ5 adhesion sites, leading to decreased cancer cell proliferation, spreading, and migration. Conversely, lower membrane tension promotes the formation of FAs, which correlates with the softer membranes observed in cancer cells, thus potentially facilitating cancer progression. Our research provides novel insights into the biomechanical regulation of CCACs and FAs, revealing their critical and contrasting roles in modulating cancer cell progression.

Transcriptome Analysis Reveals Anti-Cancer Effects of Isorhapontigenin (ISO) on Highly Invasive Human T24 Bladder Cancer Cells

Bladder cancer, the most common malignancy of the urinary tract, has a poor overall survival rate when the tumor becomes muscle invasive. The discovery and evaluation of new alternative medications targeting high-grade muscle invasive bladder cancer (MIBC) are of tremendous importance in reducing bladder cancer mortality. Isorhapontigenin (ISO), a stilbene derivative from the Chinese herb Gnetum cleistostachyum, exhibits a strong anti-cancer effect on MIBCs. Here, we report the whole transcriptome profiling of ISO-treated human bladder cancer T24 cells. A total of 1047 differentially expressed genes (DEGs) were identified, including 596 downregulated and 451 upregulated genes. Functional annotation and pathway analysis revealed that ISO treatment induced massive changes in gene expression associated with cell movement, migration, invasion, metabolism, proliferation, and angiogenesis. Additionally, ISO treatment-activated genes involved in the inflammatory response but repressed genes involved in hypoxia signaling, glycolysis, the actin cytoskeleton, and the tumor microenvironment. In summary, our whole transcriptome analysis demonstrated a shift in metabolism and altered actin cytoskeleton in ISO-treated T24 cells, which subsequently contribute to tumor microenvironment remodeling that suppresses tumor growth and progression.

Implanting mechanically reprogrammed fibroblasts for aged tissue regeneration and wound healing

Cell-based therapies are essential for tissue regeneration and wound healing during aging. Autologous transplantation of aging cells is ineffective due to their increased senescence and reduced tissue remodeling capabilities. Alternatively, implanting reprogrammed aged cells provides unique opportunities. In this paper, we demonstrate the implantation of partially reprogrammed aged human dermal fibroblasts into in vitro aged skin models for tissue regeneration and wound healing. The partially reprogrammed cells were obtained using our previously reported, highly efficient mechanical approach. Implanted cells showed enhanced expression of extracellular matrix proteins in the large area of aged tissue. In addition, the implanted cells at wound sites showed increased extracellular matrix protein synthesis and matrix alignment. Transcriptome analysis, combined with chromatin biomarkers, revealed these implanted cells upregulated tissue regeneration and wound healing pathways. Collectively our results provide a novel, nongenetic, partial reprogramming of aged cells for cell-based therapies in regenerative medicine.

Differential impact of cytoplasmic vs. nuclear RAD51 expression on breast cancer progression and patient prognosis

RAD51 recombinase is one of the DNA damage repair proteins associated with breast cancer risk. Apart from its function to maintain genomic integrity within the cell nucleus, RAD51 localized to the cytoplasm has also been implicated in breast malignancy. However, limited information exists on the roles of cytoplasmic vs. nuclear RAD51 in breast cancer progression and patient prognosis. In the present study, the association of cytoplasmic and nuclear RAD51 with clinical outcomes of patients with breast cancer was analyzed, revealing that elevated cytoplasmic RAD51 expression was associated with breast cancer progression, including increased cancer stage, grade, tumor size, lymph node metastasis and chemoresistance, along with reduced patient survival. By contrast, elevated nuclear RAD51 expression largely had the inverse effect. Results from in vitro investigations supported the cancer‑promoting effect of RAD51, showing that overexpression of RAD51 promoted breast cancer cell growth, chemoresistance and metastatic ability, while knockdown of RAD51 repressed these malignant behaviors. The current data suggest that differential expression of subcellular RAD51 had a distinct impact on breast cancer progression and patient survival. Specifically, cytoplasmic RAD51 in contrast to nuclear RAD51 was potentially an adverse marker in breast cancer.

E3 Ubiquitin Ligase Uhrf2 Knockout Reveals a Critical Role in Social Behavior and Synaptic Plasticity in the Hippocampus

The hippocampal formation, particularly the CA2 subregion, is critical for social memory formation and memory processing, relying on synaptic plasticity-a fundamental mechanism by which synapses strengthen. Given the role of the ubiquitin-proteasome system (UPS) in various nervous system processes, including learning and memory, we were particularly interested in exploring the involvement of RING-type ubiquitin E3 ligases, such as UHRF2 (NIRF), in social behavior and synaptic plasticity. Our results revealed altered social behavior in mice with systemic Uhrf2 knockout, including changes in nest building, tube dominance, and the three-chamber social novelty test. In Uhrf2 knockout mice, the entorhinal cortex-CA2 circuit showed significant reductions in synaptic plasticity during paired-pulse facilitation and long-term potentiation, while the inability to evoke synaptic plasticity in the Schaffer-collateral CA2 synapses remained unaffected. These changes in synaptic plasticity correlated with significant changes in gene expression including genes related to vesicle trafficking and transcriptional regulation. The effects of Uhrf2 knockout on synaptic plasticity and the observed gene expression changes highlight UHRF2 as a regulator of learning and memory processes at both the cellular and systemic levels. Targeting E3 ubiquitin ligases, such as UHRF2, may hold therapeutic potential for memory-related disorders, warranting further investigation.

S100A11 promotes focal adhesion disassembly via myosin II-driven contractility and Piezo1-mediated Ca2+ entry

S100A11 is a small Ca2+-activatable protein known to localize along stress fibers (SFs). Analyzing S100A11 localization in HeLa and U2OS cells further revealed S100A11 enrichment at focal adhesions (FAs). Strikingly, S100A11 levels at FAs increased sharply, yet transiently, just before FA disassembly. Elevating intracellular Ca2+ levels with ionomycin stimulated both S100A11 recruitment and subsequent FA disassembly. However, pre-incubation with the non-muscle myosin II (NMII) inhibitor blebbistatin or with an inhibitor of the stretch-activatable Ca2+ channel Piezo1 suppressed S100A11 recruitment, implicating S100A11 in an actomyosin-driven FA recruitment mechanism involving Piezo1-dependent Ca2+ influx. Applying external forces on peripheral FAs likewise recruited S100A11 to FAs even if NMII activity was inhibited, corroborating the mechanosensitive recruitment mechanism of S100A11. However, extracellular Ca2+ and Piezo1 function were indispensable, indicating that NMII contraction forces act upstream of Piezo1-mediated Ca2+ influx, in turn leading to S100A11 activation and FA recruitment. S100A11-knockout cells display enlarged FAs and had delayed FA disassembly during cell membrane retraction, consistent with impaired FA turnover in these cells. Our results thus demonstrate a novel function for S100A11 in promoting actomyosin contractility-driven FA disassembly.

Selection of reference genes in liproxstatin-1-treated K562 Leukemia cells via RT-qPCR and RNA sequencing

BACKGROUND

Reverse transcription quantitative polymerase chain reaction (RT-qPCR) can accurately detect relative gene expression levels in biological samples. However, widely used reference genes exhibit unstable expression under certain conditions.

METHODS AND RESULTS

Here, we compared the expression stability of eight reference genes (RPLP0, RPS18, RPL13, EEF1A1, β-actin, GAPDH, HPRT1, and TUBB) commonly used in liproxstatin-1 (Lip-1)-treated K562 cells using RNA-sequencing and RT-qPCR. The expression of EEF1A1, ACTB, GAPDH, HPRT1, and TUBB was considerably lower in cells treated with 20 μM Lip-1 than in the control, and GAPDH also showed significant downregulation in the 10 μM Lip-1 group. Meanwhile, when we used geNorm, NormFinder, and BestKeeper to compare expression stability, we found that GAPDH and HPRT1 were the most unstable reference genes among all those tested. Stability analysis yielded very similar results when geNorm or BestKeeper was used but not when NormFinder was used. Specifically, geNorm and BestKeeper identified RPL13 and RPLP0 as the most stable genes under 20 μM Lip-1 treatment, whereas RPL13, EEF1A1, and TUBB were the most stable under 10 μM Lip-1 treatment. TUBB and EEF1A1 were the most stable genes in both treatment groups according to the results obtained using NormFinder. An assumed most stable gene was incorporated into each software to validate the accuracy. The results suggest that NormFinder is not an appropriate algorithm for this study.

CONCLUSIONS

Stable reference genes were recognized using geNorm and BestKeeper but not NormFinder. Overall, RPL13 and RPLP0 were the most stable reference genes under 20 μM Lip-1 treatment, whereas RPL13, EEF1A1, and TUBB were the most stable genes under 10 μM Lip-1 treatment.

Regulation of Angiogenesis by Non-Coding RNAs in Cancer

Non-coding RNAs, including microRNAs, long non-coding RNAs, and circular RNAs, have been identified as crucial regulators of various biological processes through epigenetic regulation, transcriptional regulation, and post-transcriptional regulation. Growing evidence suggests that dysregulation and activation of non-coding RNAs are closely associated with tumor angiogenesis, a process essential for tumor growth and metastasis and a major contributor to cancer-related mortality. Therefore, understanding the molecular mechanisms underlying tumor angiogenesis is of utmost importance. Numerous studies have documented the involvement of different types of non-coding RNAs in the regulation of angiogenesis. This review provides an overview of how non-coding RNAs regulate tumor angiogenesis. Additionally, we discuss emerging strategies that exploit non-coding RNAs for anti-angiogenic therapy in cancer treatment. Ultimately, this review underscores the crucial role played by non-coding RNAs in tumor angiogenesis and highlights their potential as therapeutic targets for anti-angiogenic interventions against cancer.

Multiple approaches revealed MGc80-3 as a somatic hybrid with HeLa cells rather than a gastric cancer cell line

The short-tandem-repeats (STR) profiles of MGc80-3 and HeLa partially overlap, raising suspicion of contamination in the MGc80-3 cell line. However, there has not been any relevant study demonstrating whether MGc80-3 was fully replaced by HeLa cells, just mixed with HeLa cells (co-existing), or was a somatic hybrid with HeLa cells. In addition to STR profiling, various approaches, including single nucleotide polymorphisms genotyping, polymerase chain reaction, screening for human papillomaviruses type 18 (HPV-18) fragment, chromosome karyotyping, pathological examination of xenografts, tissue-specific-90-gene expression signature and high-throughput RNA sequencing were used to determine the nature of MGc80-3. Our study found that the abnormal STR profile, partially overlapping with that of HeLa cells (64.62% to 71.64%), could not verify MGc80-3 as a HeLa cell line. However, the STR 13.3 repeat allele in the D13S317 locus that seemed to be unique to HeLa cells was detected in MGc80-3. Almost all the MGc80-3 cells exhibited HPV-18 fragments in the genome as well as certain HeLa marker chromosomes, such as M7 and M12. The molecular assay of the 90-gene expression signature still considered MGc80-3 as a stomach cancer using an algorithmic analysis. The expression pattern of multiple genes in MGc80-3 was quite different from that in HeLa cells, which showed that certain characteristics belonged to gastric cancer cell lines. High throughput RNA sequencing showed the distinct patterns of gene expression in MGc80-3. In conclusion, MGc80-3 cell line is a somatic hybrid with HeLa cells rather than a pure gastric cancer cell line.

Detection of neoplastic-immune hybrid cells with metastatic properties in uveal melanoma

Background

Uveal melanoma is the most common non-cutaneous melanoma and is an intraocular malignancy affecting nearly 7,000 individuals per year worldwide. Of these, approximately 50% will progress to metastatic disease for which there are currently no effective therapies. Despite advances in molecular profiling and metastatic stratification of uveal melanoma tumors, little is known regarding their underlying biology of metastasis. Our group has identified a disseminated neoplastic cell population characterized by co-expression of immune and melanoma proteins, circulating hybrid cells (hybrids), in patients with uveal melanoma. Compared to circulating tumor cells, which lack expression of immune proteins, hybrids are detected at an increased prevalence in peripheral blood and can be used as a non-invasive biomarker to predict metastatic progression.

Methods

To ascertain mechanisms underlying enhanced hybrid cell dissemination we identified hybrid cells within primary uveal melanoma tumors using single cell RNA sequencing and evaluated their gene expression and predicted ligand-receptor interactions in relation to other melanoma and immune cells within the primary tumor. We then verified expression of upregulated hybrid pathways within patient-matched tumor and peripheral blood hybrids using cyclic immunofluorescence and quantified their protein expression relative to other non-hybrid tumor and disseminated tumor cells.

Results

Among the top upregulated genes and pathways in hybrid cells were those involved in enhanced cell motility and cytoskeletal rearrangement, immune evasion, and altered cellular metabolism. In patient-matched tumor and peripheral blood, we verified gene expression by examining concordant protein expression for each pathway category: TMSB10 (cell motility), CD74 (immune evasion) and GPX1 (metabolism). Both TMSB10 and GPX1 were expressed on significantly higher numbers of disseminated hybrid cells compared to circulating tumor cells, and CD74 and GPX1 were expressed on more disseminated hybrids than tumor-resident hybrids. Lastly, we identified that hybrid cells express ligand-receptor signaling pathways implicated in promoting metastasis including GAS6-AXL, CXCL12-CXCR4, LGALS9-P4HB and IGF1-IGFR1.

Conclusion

These findings highlight the importance of TMSB10, GPX1 and CD74 for successful hybrid cell dissemination and survival in circulation. Our results contribute to the understanding of uveal melanoma tumor progression and interactions between tumor cells and immune cells in the tumor microenvironment that may promote metastasis.

Identification and characterization of ARID1A-interacting proteins in renal tubular cells and their molecular regulation of angiogenesis

BACKGROUND

Defects and deficiency of AT-rich interactive domain-containing protein 1A (ARID1A) encoded by a tumor suppressor gene ARID1A have recently been suggested to get involved in angiogenesis, a crucial process in carcinogenesis. However, molecular mechanisms of ARID1A deficiency to induce angiogenesis in kidney cancer remain underinvestigated.

METHODS

We performed large-scale identification of ARID1A protein interactors in renal tubular epithelial cells (RTECs) using immunoprecipitation (IP) followed by nanoLC-ESI-LTQ-Orbitrap tandem mass spectrometry (MS/MS). Their roles in angiogenesis were investigated using various assays.

RESULTS

A total of 74 ARID1A-interacting proteins were identified. Protein-protein interactions analysis revealed that these identified proteins interacted directly or indirectly with ARID1A. Among them, the direct interaction between ARID1A and β-actin was validated by IP and reciprocal IP followed by Western blotting. Small interfering RNA (siRNA) was used for single and double knockdowns of ARID1A and ACTB. Semi-quantitative RT-PCR demonstrated that deficiency of ARID1A, but not ACTB, significantly affected expression of angiogenesis-related genes in RTECs (VEGF and FGF2 were increased, whereas PDGF and EGF were decreased). However, the knockdowns did not affect TGFB1 and FGF1 levels. The quantitative mRNA expression data of VEGF and TGFB1 were consistent with the secreted levels of their protein products as measured by ELISA. Only secreted products derived from ARID1A-deficient RTECs significantly increased endothelial cells (ECs) migration and tube formation. Some of the other carcinogenic features could also be confirmed in the ARID1A-deficient RTECs, including increased cell migration and chemoresistance. Double knockdowns of both ARID1A and ACTB did not enhance the effects of single ARID1A knockdown in all assays.

CONCLUSIONS

We report herein a large dataset of the ARID1A-interacting proteins in RTECs using an IP-MS/MS approach and confirm the direct interaction between ARID1A and β-actin. However, the role of ARID1A deficiency in angiogenesis is independent of β-actin.

Peptidome analysis reveals critical roles for peptides in a rat model of intestinal ischemia/reperfusion injury

Intestinal ischemia/reperfusion injury (IIRI) has the potential to be life threatening and is associated with significant morbidity and serious damage to distant sites in the body on account of disruption of the intestinal mucosal barrier. In the present study, we have explored this line of research by comparing and identifying peptides that originated from the intestinal segments of IIRI model rats by using liquid chromatography-mass spectrometry (LC-MS). We also analyzed the basic characteristics, cleavage patterns, and functional domains of differentially expressed peptides (DEPs) between the IIRI model rats and control (sham-operated) rats and identified bioactive peptides that are potentially associated with ischemia reperfusion injury. We also performed bioinformatics analyses in order to identify the biological roles of the DEPs based on their precursor proteins. Enrichment analysis demonstrated the role of several DEPs in impairment of the intestinal mucosal barrier caused by IIRI. Based on the results of comprehensive ingenuity pathway analysis, we identified the DEPs that were significantly correlated with IIRI. We identified a candidate precursor protein (Actg2) and seven of its peptides, and we found that Actg2-6 had a more significant difference in its expression, a longer half-life, and better lipophilicity, hydrophobicity, and stability than the other candidate Actg2 peptides examined. Furthermore, we observed that Actg2-6 might play critical roles in the protection of the intestinal mucosal barrier during IIRI. In summary, our study provides a better understanding of the peptidomics profile of IIRI, and the results indicate that Actg2-6 could be a useful target in the treatment of IIRI.

Analysis of uveal melanoma scRNA sequencing data identifies neoplastic-immune hybrid cells that exhibit metastatic potential

Uveal melanoma (UM) is the most common non-cutaneous melanoma and is an intraocular malignancy that affects nearly 7,000 individuals per year worldwide. Of these, nearly 50% will progress to metastatic disease for which there are currently no effective therapies. Despite advances in the molecular profiling and metastatic stratification of class 1 and 2 UM tumors, little is known regarding the underlying biology of UM metastasis. Our group has identified a disseminated tumor cell population characterized by co-expression of immune and melanoma proteins, (circulating hybrid cells (CHCs), in patients with UM. Compared to circulating tumor cells, CHCs are detected at an increased prevalence in peripheral blood and can be used as a non-invasive biomarker to predict metastatic progression. To identify mechanisms underlying enhanced hybrid cell dissemination we sought to identify hybrid cells within a primary UM single cell RNA-seq dataset. Using rigorous doublet discrimination approaches, we identified UM hybrids and evaluated their gene expression, predicted ligand-receptor status, and cell-cell communication state in relation to other melanoma and immune cells within the primary tumor. We identified several genes and pathways upregulated in hybrid cells, including those involved in enhancing cell motility and cytoskeleton rearrangement, evading immune detection, and altering cellular metabolism. In addition, we identified that hybrid cells express ligand-receptor signaling pathways implicated in promoting cancer metastasis including IGF1-IGFR1, GAS6-AXL, LGALS9-P4HB, APP-CD74 and CXCL12-CXCR4. These results contribute to our understanding of tumor progression and interactions between tumor cells and immune cells in the UM microenvironment that may promote metastasis.

Actin Alpha 2, Smooth Muscle (ACTA2) Is Involved in the Migratory Potential of Malignant Gliomas, and Its Increased Expression at Recurrence Is a Significant Adverse Prognostic Factor

Malignant glioma is a highly invasive tumor, and elucidating the glioma invasion mechanism is essential for developing novel therapies. We aimed to highlight actin alpha 2, smooth muscle (ACTA2) as potential biomarkers of brain invasion and distant recurrence in malignant gliomas. Using the human malignant glioma cell line, U251MG, we generated ACTA2 knockdown (KD) cells treated with small interfering RNA, and the cell motility and proliferation of the ACTA2 KD group were analyzed. Furthermore, tumor samples from 12 glioma patients who underwent reoperation at the time of tumor recurrence were utilized to measure ACTA2 expression in the tumors before and after recurrence. Thereafter, we examined how ACTA2 expression correlates with the time to tumor recurrence and the mode of recurrence. The results showed that the ACTA2 KD group demonstrated a decline in the mean motion distance and proliferative capacity compared to the control group. In the clinical glioma samples, ACTA2 expression was remarkably increased in recurrent samples compared to the primary samples from the same patients, and the higher the change in ACTCA2 expression from the start to relapse, the shorter the progression-free survival. In conclusion, ACTA2 may be involved in distant recurrence in clinical gliomas.

Cytotoxicity of poly-guanidine in medulloblastoma cell lines

Medulloblastoma (MB) is the most common pediatric brain tumor. The therapy frequently causes serious side effects, and new selective therapies are needed. MB expresses hyper sialylation, a possible target for selective therapy. The cytotoxic efficacy of a poly guanidine conjugate (GuaDex) incubated with medulloblastoma cell cultures (DAOY and MB-LU-181) was investigated. The cells were incubated with 0.05-8 µM GuaDex from 15 min to 72 h. A fluorometric cytotoxicity assay (FMCA) measured the cytotoxicity. Labeled GuaDex was used to study tumor cell interaction. FITC-label Sambucus nigra confirmed high expression of sialic acid (Sia). Immunofluorescence microscopy was used to visualize the cell F-actin and microtubules. The cell interactions were studied by confocal and fluorescence microscopy. Annexin-V assay was used to detect apoptosis. Cell cycle analysis was done by DNA content determination. A wound-healing migration assay determined the effects on the migratory ability of DAOY cells after GuaDex treatment. IC50 for GuaDex was 223.4 -281.1 nM. FMCA showed potent growth inhibition on DAOY and MB-LU-181 cells at 5 uM GuaDex after 4 h of incubation. GuaDex treatment induced G2/M phase cell cycle arrest. S. nigra FITC-label lectin confirmed high expression of Sia on DAOY medulloblastoma cells. The GuaDex treatment polymerized the cytoskeleton (actin filaments and microtubules) and bound to DNA, inducing condensation. The Annexin V assay results were negative. Cell migration was inhibited at 0.5 µM GuaDex concentration after 24 h of incubation. GuaDex showed potent cytotoxicity and invasion-inhibitory effects on medulloblastoma cells at low micromolar concentrations. GuaDex efficacy was significant and warrants further studies.

Functionalized Parylene Films for Enhancement of Antibody Production by Hybridoma Cells

In this study, the influence of microenvironments on antibody production of hybridoma cells was analyzed using six types of functionalized parylene films, parylene-N and parylene-C (before and after UV radiation), parylene-AM, and parylene-H, and using polystyrene as a negative control. Hybridoma cells were cultured on modified parylene films that produced a monoclonal antibody against the well-known fungal toxin ochratoxin-A. Surface properties were analyzed for each parylene film, such as roughness, chemical functional groups, and hydrophilicity. The proliferation rate of the hybridoma cells was observed for each parylene film by counting the number of adherent cells, and the total amount of produced antibodies from different parylene films was estimated using indirect ELISA. In comparison with the polystyrene, the antibody-production by parylene-H and parylene-AM was estimated to be observed to be as high as 210-244% after the culture of 24 h. These results indicate that the chemical functional groups of the culture plate could influence antibody production. To analyze the influence of the microenvironments of the modified parylene films, we performed cell cycle analysis to estimate the ratio of the G0/G1, S, and G2/M phases of the hybridoma cells on each parylene film. From the normalized proportion of phases of the cell cycle, the difference in antibody production from different surfaces was considered to result from the difference in the proliferation rate of hybridoma cells, which occurred from the different physical and chemical properties of the parylene films. Finally, protein expression was analyzed using an mRNA array to determine the effect of parylene films on protein expression in hybridoma cells. The expression of three antibody production-related genes (CD40, Sox4, and RelB) was analyzed in hybridoma cells cultured on modified parylene films.

Vascular Endothelial Growth Factor-D (VEGF-D): An Angiogenesis Bypass in Malignant Tumors

Vascular endothelial growth factors (VEGFs) are the key regulators of vasculogenesis in normal and oncological development. VEGF-A is the most studied angiogenic factor secreted by malignant tumor cells under hypoxic and inflammatory stress, which made VEGF-A a rational target for anticancer therapy. However, inhibition of VEGF-A by monoclonal antibody drugs led to the upregulation of VEGF-D. VEGF-D was primarily described as a lymphangiogenic factor; however, VEGF-D's blood angiogenic potential comparable to VEGF-A has already been demonstrated in glioblastoma and colorectal carcinoma. These findings suggested a role for VEGF-D in facilitating malignant tumor growth by bypassing the anti-VEGF-A antiangiogenic therapy. Owing to its high mitogenic ability, higher affinity for VEGFR-2, and higher expression in cancer, VEGF-D might even be a stronger angiogenic driver and, hence, a better therapeutic target than VEGF-A. In this review, we summarized the angiogenic role of VEGF-D in blood vasculogenesis and its targetability as an antiangiogenic therapy in cancer.

Exosomal PGAM1 promotes prostate cancer angiogenesis and metastasis by interacting with ACTG1

Tumor-derived exosomes and their contents promote cancer metastasis. Phosphoglycerate mutase 1 (PGAM1) is involved in various cancer-related processes. Nevertheless, the underlying mechanism of exosomal PGAM1 in prostate cancer (PCa) metastasis remains unclear. In this study, we performed in vitro and in vivo to determine the functions of exosomal PGAM1 in the angiogenesis of patients with metastatic PCa. We performed Glutathione-S-transferase pulldown, co-immunoprecipitation, western blotting and gelatin degradation assays to determine the pathway mediating the effect of exosomal PGAM1 in PCa. Our results revealed a significant increase in exosomal PGAM1 levels in the plasma of patients with metastatic PCa compared to patients with non-metastatic PCa. Furthermore, PGAM1 was a key factor initiating PCa cell metastasis by promoting invadopodia formation and could be conveyed by exosomes from PCa cells to human umbilical vein endothelial cells (HUVECs). In addition, exosomal PGAM1 could bind to γ-actin (ACTG1), which promotes podosome formation and neovascular sprouting in HUVECs. In vivo results revealed exosomal PGAM1 enhanced lung metastasis in nude mice injected with PCa cells via the tail vein. In summary, exosomal PGAM1 promotes angiogenesis and could be used as a liquid biopsy marker for PCa metastasis.

Assessment of emerging pretraining strategies in interpretable multimodal deep learning for cancer prognostication

BACKGROUND

Deep learning models can infer cancer patient prognosis from molecular and anatomic pathology information. Recent studies that leveraged information from complementary multimodal data improved prognostication, further illustrating the potential utility of such methods. However, current approaches: 1) do not comprehensively leverage biological and histomorphological relationships and 2) make use of emerging strategies to "pretrain" models (i.e., train models on a slightly orthogonal dataset/modeling objective) which may aid prognostication by reducing the amount of information required for achieving optimal performance. In addition, model interpretation is crucial for facilitating the clinical adoption of deep learning methods by fostering practitioner understanding and trust in the technology.

METHODS

Here, we develop an interpretable multimodal modeling framework that combines DNA methylation, gene expression, and histopathology (i.e., tissue slides) data, and we compare performance of crossmodal pretraining, contrastive learning, and transfer learning versus the standard procedure.

RESULTS

Our models outperform the existing state-of-the-art method (average 11.54% C-index increase), and baseline clinically driven models (average 11.7% C-index increase). Model interpretations elucidate consideration of biologically meaningful factors in making prognosis predictions.

DISCUSSION

Our results demonstrate that the selection of pretraining strategies is crucial for obtaining highly accurate prognostication models, even more so than devising an innovative model architecture, and further emphasize the all-important role of the tumor microenvironment on disease progression.

JUN-induced super-enhancer RNA forms R-loop to promote nasopharyngeal carcinoma metastasis

Oncogenic super-enhancers (SEs) generate noncoding enhancer/SE RNAs (eRNAs/seRNAs) that exert a critical function in malignancy through powerful regulation of target gene expression. Herein, we show that a JUN-mediated seRNA can form R-loop to regulate target genes to promote metastasis of nasopharyngeal carcinoma (NPC). A combination of global run-on sequencing, chromatin-immunoprecipitation sequencing, and RNA sequencing was used to screen seRNAs. A specific seRNA associated with NPC metastasis (seRNA-NPCM) was identified as a transcriptional regulator for N-myc downstream-regulated gene 1 (NDRG1). JUN was found to regulate seRNA-NPCM through motif binding. seRNA-NPCM was elevated in NPC cancer tissues and highly metastatic cell lines, and promoted the metastasis of NPC cells in vitro and in vivo. Mechanistically, the 3' end of seRNA-NPCM hybridizes with the SE region to form an R-loop, and the middle segment of seRNA-NPCM binds to heterogeneous nuclear ribonucleoprotein R (hnRNPR) at the promoter of distal gene NDRG1 and neighboring gene tribbles pseudokinase 1 (TRIB1). These structures promote chromatin looping and long-distance chromatin interactions between SEs and promoters, thus facilitating NDRG1 and TRIB1 transcription. Furthermore, the clinical analyses showed that seRNA-NPCM and NDRG1 were independent prognostic factors for NPC patients. seRNA-NPCM plays a critical role in orchestrating target gene transcription to promote NPC metastasis.

Proteomics analysis of human breast milk by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) coupled with mass spectrometry to assess breast cancer risk

Breast cancer (BC) is one of the most common cancers and one of the most common causes for cancer-related mortality. Discovery of protein biomarkers associated with cancer is considered important for early diagnosis and prediction of the cancer risk. Protein biomarkers could be investigated by large-scale protein investigation or proteomics, using mass spectrometry (MS)-based techniques. Our group applies MS-based proteomics to study the protein pattern in human breast milk from women with BC and controls and investigates the alterations and dysregulations of breast milk proteins in comparison pairs of BC versus control. These dysregulated proteins might be considered potential future biomarkers of BC. Identification of potential biomarkers in breast milk may benefit young women without BC, but who could collect the milk for future assessment of BC risk. Previously we identified several dysregulated proteins in different sets of human breast milk samples from BC patients and controls using gel-based protein separation coupled with MS. Here, we performed 2D-PAGE coupled with nano-liquid chromatography-tandem MS (nanoLC-MS/MS) in a small-scale study on a set of six human breast milk pairs (three BC samples vs. three controls) and we identified several dysregulated proteins that have potential roles in cancer progression and might be considered potential BC biomarkers in the future.

New advances in the research of clinical treatment and novel anticancer agents in tumor angiogenesis

In 1971, Folkman proposed that tumors could be limited to very small sizes by blocking angiogenesis. Angiogenesis is the generation of new blood vessels from pre-existing vessels, considered to be one of the important processes in tumor growth and metastasis. Angiogenesis is a complex process regulated by various factors and involves many secreted factors and signaling pathways. Angiogenesis is important in the transport of oxygen and nutrients to the tumor during tumor development. Therefore, inhibition of angiogenesis has become an important strategy in the clinical management of many solid tumors. Combination therapies of angiogenesis inhibitors with radiotherapy and chemotherapy are often used in clinical practice. In this article, we will review common targets against angiogenesis, the most common and up-to-date anti-angiogenic drugs and clinical treatments in recent years, including active ingredients from chemical and herbal medicines.

Mechanobiology and survival strategies of circulating tumor cells: a process towards the invasive and metastatic phenotype

Metastatic progression is the deadliest feature of cancer. Cancer cell growth, invasion, intravasation, circulation, arrest/adhesion and extravasation require specific mechanical properties to allow cell survival and the completion of the metastatic cascade. Circulating tumor cells (CTCs) come into contact with the capillary bed during extravasation/intravasation at the beginning of the metastatic cascade. However, CTC mechanobiology and survival strategies in the bloodstream, and specifically in the microcirculation, are not well known. A fraction of CTCs can extravasate and colonize distant areas despite the biomechanical constriction forces that are exerted by the microcirculation and that strongly decrease tumor cell survival. Furthermore, accumulating evidence shows that several CTC adaptations, via molecular factors and interactions with blood components (e.g., immune cells and platelets inside capillaries), may promote metastasis formation. To better understand CTC journey in the microcirculation as part of the metastatic cascade, we reviewed how CTC mechanobiology and interaction with other cell types in the bloodstream help them to survive the harsh conditions in the circulatory system and to metastasize in distant organs.

The Role of non-muscle actin paralogs in cell cycle progression and proliferation

Uncontrolled cell proliferation leads to several pathologies, including cancer. Thus, this process must be tightly regulated. The cell cycle accounts for cell proliferation, and its progression is coordinated with changes in cell shape, for which cytoskeleton reorganization is responsible. Rearrangement of the cytoskeleton allows for its participation in the precise division of genetic material and cytokinesis. One of the main cytoskeletal components is filamentous actin-based structures. Mammalian cells have at least six actin paralogs, four of which are muscle-specific, while two, named β- and γ-actin, are abundantly present in all types of cells. This review summarizes the findings that establish the role of non-muscle actin paralogs in regulating cell cycle progression and proliferation. We discuss studies showing that the level of a given non-muscle actin paralog in a cell influences the cell's ability to progress through the cell cycle and, thus, proliferation. Moreover, we elaborate on the non-muscle actins' role in regulating gene transcription, interactions of actin paralogs with proteins involved in controlling cell proliferation, and the contribution of non-muscle actins to different structures in a dividing cell. The data cited in this review show that non-muscle actins regulate the cell cycle and proliferation through varying mechanisms. We point to the need for further studies addressing these mechanisms.

Chronic ethanol exposure induces mitochondrial dysfunction and alters gene expression and metabolism in human cardiac spheroids

BACKGROUND

Chronic alcohol consumption in adults can induce various cardiac toxicities such as arrhythmias, cardiomyopathy, and heart failure. Prenatal alcohol exposure can increase the risk of developing congenital heart defects among offspring. Understanding the molecular mechanisms underlying long-term alcohol exposure-induced cardiotoxicity can help guide the development of therapeutic strategies.

METHODS

Cardiomyocytes derived from human-induced pluripotent stem cells (hiPSC-CMs) were engineered into cardiac spheroids and treated with clinically relevant concentrations of ethanol (17 and 50 mM) for 5 weeks. The cells were then analyzed for changes in mitochondrial features, transcriptomic and metabolomic profiles, and integrated omics outcomes.

RESULTS

Following chronic ethanol treatment of hiPSC-CMs, a decrease in mitochondrial membrane potential and respiration and changes in expression of mitochondrial function-related genes were observed. RNA-sequencing analysis revealed changes in various metabolic processes, heart development, response to hypoxia, and extracellular matrix-related activities. Metabolomic analysis revealed dysregulation of energy metabolism and increased metabolites associated with the upregulation of inflammation. Integrated omics analysis further identified functional subclusters and revealed potentially affected pathways associated with cardiac toxicities.

CONCLUSION

Chronic ethanol treatment of hiPSC-CMs resulted in overall decreased mitochondrial function, increased glycolysis, disrupted fatty acid oxidation, and impaired cardiac structural development.

CEMIP-mediated hyaluronan metabolism facilitates SCLC metastasis by activating TLR2/c-Src/ERK1/2 axis

Small-cell lung cancer (SCLC) is a highly metastatic and recalcitrant malignancy. Metastasis is the major cause of death in patients with SCLC but its mechanism remains poorly understood. An imbalance of hyaluronan catabolism in the extracellular matrix accelerates malignant progression in solid cancers due to the accumulation of low-molecular-weight HA. We previously found that CEMIP, a novel hyaluronidase, may act as a metastatic trigger in SCLC. In the present study, we found that both CEMIP and HA levels were higher in SCLC tissues than in paracancerous tissues from patient specimens and in vivo orthotopic models. Additionally, high expression of CEMIP was associated with lymphatic metastasis in patients with SCLC, and in vitro results showed that CEMIP expression was elevated in SCLC cells relative to human bronchial epithelial cells. Mechanistically, CEMIP facilitates the breakdown of HA and accumulation of LMW-HA. LMW-HA activates its receptor TLR2, and subsequently recruits c-Src to activate ERK1/2 signalling, thereby promoting F-actin rearrangement as well as migration and invasion of SCLC cells. In addition, the in vivo results verified that depletion of CEMIP attenuated HA levels and the expressions of TLR2, c-Src, and phosphorylation of ERK1/2, as well as liver and brain metastasis in SCLC xenografts. Furthermore, the application of the actin filament inhibitor latrunculin A significantly inhibited the liver and brain metastasis of SCLC in vivo. Collectively, our findings reveal the critical role of CEMIP-mediated HA degradation in SCLC metastasis and suggest its translational potential as an attractive target and a novel strategy for SCLC therapy.

A protein microarray-based serum proteomic investigation reveals distinct autoantibody signature in colorectal cancer

PURPOSE

Colorectal cancer (CRC) has been reported as the second leading cause of cancer death worldwide. The 5-year annual survival is around 50%, mainly due to late diagnosis, striking necessity for early detection. This study aims to identify autoantibody in patients' sera for early screening of cancer.

EXPERIMENTAL DESIGN

The study used a high-density human proteome array with approximately 17,000 recombinant proteins. Screening of sera from healthy individuals, CRC from Indian origin, and CRC from middle-east Asia origin were performed. Bio-statistical analysis was performed to identify significant autoantibodies altered. Pathway analysis was performed to explore the underlying mechanism of the disease.

RESULTS

The comprehensive proteomic analysis revealed dysregulation of 15 panels of proteins including CORO7, KCNAB1, WRAP53, NDUFS6, KRT30, and COLGALT2. Further biological pathway analysis for the top dysregulated autoantigenic proteins revealed perturbation in important biological pathways such as ECM degradation and cytoskeletal remodeling etc. CONCLUSIONS AND CLINICAL RELEVANCE: The generation of an autoimmune response against cancer-linked pathways could be linked to the screening of the disease. The process of immune surveillance can be detected at an early stage of cancer. Moreover, AAbs can be easily extracted from blood serum through the least invasive test for disease screening.

Anti-Proliferative and Pro-Apoptotic vLMW Fucoidan Formulas Decrease PD-L1 Surface Expression in EBV Latency III and DLBCL Tumoral B-Cells by Decreasing Actin Network

Epstein-Barr virus (EBV) infects 95% of the world's population and persists latently in the body. It immortalizes B-cells and is associated with lymphomas. LCLs (lymphoblastoid cell lines, EBV latency III B-cells) inhibit anti-tumoral T-cell response following PD-L1 overexpression (programmed death-ligand 1 immune checkpoint). Many cancer cells, including some DLBCLs (diffuse large B-cell lymphomas), also overexpress PD-L1. Immunotherapies are based on inhibition of PD-L1/PD-1 interactions but present some dose-dependent toxicities. We aim to find new strategies to improve their efficiency by decreasing PD-L1 expression. Fucoidan, a polysaccharide extracted from brown seaweed, exhibits immunomodulatory and anti-tumor activities depending on its polymerization degree, but data are scarce on lymphoma cells or immune checkpoints. LCLs and DLBCLs cells were treated with native fucoidan (Fucus vesiculosus) or original very-low-molecular-weight fucoidan formulas (vLMW-F). We observed cell proliferation decrease and apoptosis induction increase with vLMW-F and no toxicity on normal B- and T-cells. We highlighted a decrease in transcriptional and PD-L1 surface expression, even more efficient for vLMW than native fucoidan. This can be explained by actin network alteration, suggesting lower fusion of secretory vesicles carrying PD-L1 with the plasma membrane. We propose vLMW-F as potential adjuvants to immunotherapy due to their anti-proliferative and proapoptotic effects and ability to decrease PD-L1 membrane expression.

Identification of risk for ovarian disease enhanced by BPB or BPAF exposure

The ban on bisphenol A (BPA) has led to a rapid increase in the use of BPA analogs, and they are increasingly being detected in the natural environment and biological organisms. Studies have pointed out that BPA analogs can lead to adverse health outcomes. However, their interference with ovarian tissue has not been fully elucidated. In this study, seven- to eight-week-old CD-1 mice were exposed to corn oil containing 300 μg/kg/day bisphenol B (BPB) or bisphenol AF (BPAF) through oral gavage, and ovarian tissues were collected at 14 and 28 days of exposure. Ovarian toxicity was evaluated by the ovarian index, ovarian area, and follicle number. mRNA-seq was used to identify differentially expressed genes (DEGs) and infer the association of DEGs with ovarian diseases. BPB or BPAF exposure induced morphological changes in ovarian tissue in CD-1 mice. In addition, Gene Ontology (GO) analysis revealed disturbances in biological processes (BP) associated with steroid biosynthetic process (GO:0006694) and cellular calcium ion homeostasis (GO:0006874). Subsequently, regulatory networks of BPA analogs (BPB or BPAF)-DEGs-ovarian diseases were constructed. Importantly, the expression levels of DEGs and transcription factors (TFs) associated with ovarian disease were altered. BPB or BPAF exposure causes damage to ovarian morphology through the synergistic effects of multiple biological processes and may be associated with altered mRNA expression profiles as a risk factor for ovarian diseases.

Targeting Breast Cancer: An Overlook on Current Strategies

Breast cancer (BC) is one of the most widely diagnosed cancers and a leading cause of cancer death among women worldwide. Globally, BC is the second most frequent cancer and first most frequent gynecological one, affecting women with a relatively low case-mortality rate. Surgery, radiotherapy, and chemotherapy are the main treatments for BC, even though the latter are often not aways successful because of the common side effects and the damage caused to healthy tissues and organs. Aggressive and metastatic BCs are difficult to treat, thus new studies are needed in order to find new therapies and strategies for managing these diseases. In this review, we intend to give an overview of studies in this field, presenting the data from the literature concerning the classification of BCs and the drugs used in therapy for the treatment of BCs, along with drugs in clinical studies.