Increased Cell Motility Research Articles

Oleanolic acid inhibits aldo-keto reductase family 1 member B10-induced cancer stemness and avoids cisplatin-based chemotherapy resistance via the Snail signaling pathway in oral squamous cell carcinoma cell lines

Background/purposeOral squamous cell carcinoma (OSCC) is a common malignancy often associated with poor prognosis due to chemoresistance. In this study, we investigated whether arecoline, a major alkaloid in betel nuts, can stimulate aldo-keto reductase family 1 member B10 (AKR1B10) levels in OSCC, promoting cancer stemness and leading to resistance to cisplatin (CDDP)-based chemotherapy. Materials and methodsGain- and Loss- of AKR1B10 functions were analyzed using WB and q-PCR of OSCC cells. Stemness, epithelial mesenchymal transition (EMT) markers, and CDDP drug resistance in overexpressed AKR1B10 were also identified. ResultsUpregulated AKR1B10 in OSCC significantly increased cell motility and aggregation. The results also showed that the canonical TGF-β1-Smad3 pathway was involved in arecoline-induced AKR1B10 expression, further increasing cancer stemness with CDDP resistance via the Snail-dependent EMT pathway. Moreover, oleanolic acid (OA) and ROS/RNS (reactive oxygen/nitrogen species) inhibitors effectively reversed AKR1B10-induced CDDP-resistance. ConclusionArecoline-induced ROS/RNS to hyper-activate AKR1B10 in tumor sphere cells via the TGF-β1-Smad3 pathway. Furthermore, AKR1B10 enhanced CDDP resistance in OSCC cells via EMT-inducing markers. Finally, Finally, OA may efficiently target CDDP resistance, reverse stemness in OSCC cells, and have the potential as a novel anticancer drug.

Insights into the interactions of plant-associated bacteria and their role in the transfer of antibiotic resistance genes from soil to plant

This study discussed the role of plant-associated microbiome in regulating ARG transfer in soil-plant systems. Results showed that target ARGs in plants were mainly derived from rhizosphere soil. Cooperative interactions among bacteria in rhizosphere soil, plant-roots, plant-shoots, and soil-roots-shoots systems occurred during ARG transfer. The number of modules and keystone taxa identified as positively correlated with ARG transfer in rhizosphere soil, roots, and shoots was 3 and 49, 3 and 41, 2 and 5, respectively. Among these modules, module 3 in roots was significantly positively correlated with module 3 in rhizosphere soils and module 2 in shoots, indicating that module 3 in roots played central hub roles in ARG transfer from rhizosphere soil to roost and shoots. This may be because module 3 in roots increased cell motility and xenobiotics biodegradation and metabolism. These keystone taxa mainly belonged to Proteobacteria that can carry ARGs to transfer in soil-plant systems, especially Clostridium-sensu_stricito and Pseudomonas in rhizosphere soil carried ARGs into the shoot. Additionally, they promoted ARG transfer by increasing plant biomass, net photosynthetic rate and water use efficiency. The findings helped reveal the mechanism of plant-associated bacterial interactions and provided understanding for potential risks of ARG transfer from soil to plants.

Dedifferentiation- and aging-induced loss of mechanical contractility and polarity in vascular smooth muscle cells: Heterogeneous changes in macroscopic and microscopic behavior of cells in serial passage culture

Dedifferentiation and aging of vascular smooth muscle cells (VSMCs) are associated with serious vascular diseases, such as arteriosclerosis and aneurysm. However, how cell dedifferentiation and aging affect cellular mechanical behaviors at the single-cell and intracellular structure levels remains unclear. An in-depth understanding of these interactions is extremely important for understanding the mechanism underlying VSMC mechanical integrity and homeostatic regulation of vascular walls. Herein, we systematically investigated changes in VSMC morphology, structure, contractility, and motility during dedifferentiation and aging induced by serial passage culture using traction force microscopy with elastic micropillar substrates, laser nanodissection of cytoskeletons, confocal fluorescence microscopy, and atomic force microscopy. We found that VSMC dedifferentiation started in the middle stage of serial passage culture, accompanied by a transient cell spreading in the cell width and decrease in contractile protein expression. Dedifferentiated VSMCs showed a significant decrease in the contraction and stiffness of individual actin stress fibers; however, their overall cell traction forces were maintained. Simultaneously, a significant increase in cell motility and the number of actin fibers was observed in dedifferentiated VSMCs, which may be associated with the enhancement of cell migration and disruption of cell/tissue integrity during the early stage of vascular diseases. As cell senescence progressed in the later stage of serial passage culture, VSMCs displayed reduced cell spreading and migration with decrease in the overall cell traction forces and drastic reduction in mechanical polarity of cell structures and forces. These results suggested that cell senescence causes loss of mechanical contractility and polarity in VSMCs, which may be an important factor in vascular disease progression. The experimental systems established in this study can be powerful tools for understanding the mechanisms underlying cellular dedifferentiation and aging from a biomechanical perspective.

Association of N-adhesin and focal adhesion kinase with frequency of tumor spread through the airspace (STAS) in stage I lung carcinoma and correlation with recurrence.

e20020 Background: Spread through air spaces (STAS) is one of the many modes of lung cancer dissemination. Aberrant activation of epithelial-mesenchymal transition (EMT) has been associated with enhanced tumor cell migration and invasiveness, a process that is accompanied by a decrease in adhesion molecules that maintain contact between epithelial cells, leading to cell separation and increased cell motility. Our objectives were to investigate the effect of adhesion molecule expression levels on STAS occurrence and postoperative recurrence in patients undergoing radical resection for stage I lung carcinoma. Methods: We examined the association of adhesion molecules with STAS as the primary endpoint and the Disease-Free Survival (DFS) as a secondary endpoint. E-cadherin, P-cadherin, N-cadherin, focal adhesion kinase (FAK), epithelial cell adhesion molecule (EpCAM) neural cell adhesion molecule 1 (NCAM1), vascular cell adhesion molecule 1 (VCAM1), intercellular cell adhesion molecule-1 (ICAM-1) were analyzed by immunohistochemistry in patients undergoing radical resection for stage I lung carcinoma. Associations between those adhesion molecules expression levels and STAS were determined by using the chi-square test and logistic regression model. DFS was analyzed by using the log-rank test and Cox proportional risk model. Results: As of January 1, 2024, 12 of 60 patients undergoing radical resection for stage I lung carcinoma had a disease recurrence. All of 60 patients’ tissue specimens were retrospectively analyzed, and there were no significant differences between patients with STAS-positive(n=30) and STAS-negative(n=30) in baseline clinicopathologic features, except for histological growth patterns, and lymphovascular invasion.Higher incidence of STAS was significantly associated with low expression of E-cadherin (P=0.002), high expression of N-cadherin (P=0.018) and FAK (P=0.027), and males (P=0.026), independent of tumor size, age, and clinical stage. Multivariate analysis showed that STAS (P=0.025), low E-cadherin/high N-cadherin (P=0.038), low E-cadherin/high FAK (P=0.025), and high N-cadherin/FAK (P=0.003) were significantly correlated with a higher risk of recurrence. In addition, females (P=0.034), and high N-cadherin/FAK (P=0.032) were associated with a high risk of recurrence in patients with STAS. Conclusions: Low expression of e-cadherin, high expression of N-cadherin and FAK were independent predictors of higher incidence of STAS. Tumors with low E-cadherin/high N-cadherin, low E-cadherin/high FAK, and high N-cadherin/FAK expression were important predictors of recurrence in patients with stage I lung carcinoma. Additionally, high N-cadherin/FAK expression in tumors provides information about a higher risk of recurrence in STAS-positive stage I lung carcinoma.

Non-pituitary growth hormone enables colon cell senescence evasion.

DNA damage-induced senescence is initially sustained by p53. Senescent cells produce a senescence-associated secretory phenotype (SASP) that impacts the aging microenvironment, often promoting cell transformation. Employing normal non-tumorous human colon cells (hNCC) derived from surgical biopsies and three-dimensional human intestinal organoids, we show that local non-pituitary growth hormone (npGH) induced in senescent cells is a SASP component acting to suppress p53. npGH autocrine/paracrine suppression of p53 results in senescence evasion and cell-cycle reentry, as evidenced by increased Ki67 and BrdU incorporation. Post-senescent cells exhibit activated epithelial-to-mesenchymal transition (EMT), and increased cell motility. Nu/J mice harboring GH-secreting HCT116 xenografts with resultant high GH levels and injected intrasplenic with post-senescent hNCC developed fourfold more metastases than did mice harboring control xenografts, suggesting that paracrine npGH enables post-senescent cell transformation. By contrast, senescent cells with suppressed npGH exhibit downregulated Ki67 and decreased soft agar colony formation. Mechanisms underlying these observations include npGH induction by the SASP chemokine CXCL1, which attracts immune effectors to eliminate senescent cells; GH, in turn, suppresses CXCL1, likely by inhibiting phospho-NFκB, resulting in SASP cytokine downregulation. Consistent with these findings, GH-receptor knockout mice exhibited increased colon phospho-NFκB and CXCL1, while GH excess decreased colon CXCL1. The results elucidate mechanisms for local hormonal regulation of microenvironmental changes in DNA-damaged non-tumorous epithelial cells and portray a heretofore unappreciated GH action favoring age-associated epithelial cell transformation.

Abstract PO2-27-08: Discovery of glucocorticoid receptor-induced EMT and integrin gene expression and increased cell motility in invasive lobular breast cancer

Abstract Estrogen receptor (ER)-positive, invasive lobular carcinoma (ILC) is the second most common histological subtype of breast cancer. Although the five-year stage-matched survival is improved compared to infiltrating ductal carcinoma (IDC), ILC late metastatic recurrences ( >5 years) are more frequent. Understanding the molecular mechanisms of lobular breast cancer’s significantly dormant yet ultimately metastatic phenotype is important to improve clinical outcomes. Our laboratory had previously shown that GR activation in ER+ IDC was associated with decreased cell proliferation, but little is known about GR activity in ER+ ILC. By examining gene expression following GR activation in metastases-derived ER+/GR+ human ILC cell lines, we recently uncovered that GR-activation increases EMT and integrin pathways. Here we show for the first time that in addition to activation of these gene expression pathways, GR activation increases ILC cellular migration in microchannels coated with collagen and fibronectin, consistent with a potential for GR activation to increase ILC metastases. We examined GR expression and activation in SUM44 GR+/GR-, and BCK4 GR+/GR- and MM134 GR+ cell lines and will present data comparing gene GR- mediated expression in the presence of cortisol and clinically relevant GR modulation. Ongoing investigations also include in vivo MIND modeling with GR modulation. Citation Format: Baylee Porter, Candace Frerich, Muriel Laine, Sunati Sahoo, Geoffrey Greene, Jeon Lee, Lynda Bennett, Suzanne Conzen. Discovery of glucocorticoid receptor-induced EMT and integrin gene expression and increased cell motility in invasive lobular breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-27-08.

Abstract PO3-24-11: Impact of Circulating Extracellular Vesicles derived from Obese Women on Pro-Tumor Functions of Stromal Fibroblasts in Breast Cancer

Abstract The incidence of obesity has risen sharply worldwide, and growing evidence shows its impact on several malignancies, including breast cancer (BC). Excessive adiposity and high body mass index (BMI) significantly affect BC incidence, prognosis, and therapeutic response of patients. Indeed, obese women exhibit larger tumor size, limph node involvement, metastatic spread, and poorer survival outcomes. Preclinical and clinical studies indicated that the obese setting provides local and systemic modifications that may stimulate BC progression and influence tumor microenvironment, particularly composed of stromal fibroblasts (SF). The mechanisms behind this interplay are likely to be multifactorial and may involve important adipocyte-derived mediators, such as adipokines and growth factors. Aside from these soluble factors, extracellular vesicles (EVs), nanoscale lipid-bilayer enclosed vesicles released by a variety of cells, are emerging as powerful regulators of cell-to-cell communication able to promote BC initiation, growth, metastatic dissemination and drug resistance. However, the potential impact of obesity-derived EVs in affecting tumor-stimulatory features of SF has not been yet investigated. To this aim, circulating EVs were isolated from the serum of women categorized as normal weight (NW; 18 > BMI < 24.9 Kg/m2) and overweight/obese (OW/Ob; BMI > 25 Kg/m2). Immortalised human mammary control fibroblasts (CF), their cancer-associated counterparts (exp-CAFs), and human CAFs, isolated from biopsies of primary BC, were used as experimental models for stromal fibroblasts. Human MCF-7 and T47D BC cells were employed as experimental cell models for mammary carcinoma in co-culture experiments. Circulating EVs were successfully extracted from the serum of NW and OW/Ob women, and characterized by their shapes, size and protein markers. Transmission Electron Microscopy (TEM), and Nanoparticle Tracking Analysis (NTA) showed that EVs in the isolated fractions were oval or bowl-shaped with a size range between 50-200 nm. In accordance with the Minimal Information for Studies of Extracellular Vesicles (MISEV) 2018, enrichment of the EV markers TSG101, CD81, and CD63 were all detected in the EV isolated fractions. Interestingly, elevated levels of circulating EVs were detected in OW/Ob women compared to NW subjects. Treatment of CF with OW/Ob-EVs resulted in an increased cell motility, invasiveness, contractility along with an up-regulation of CF markers. BC cells cocultured with conditioned medium (CM) derived from OW/Ob-EV-treated CF exhibited higher anchorage-independent growth and migratory capacity than BC cells cocultured with CM derived from NW-EV-treated CF. Moreover, OW/Ob-EVs enhanced tumor-stimulatory activities of exp-CAFs and CAFs, further highlighting how obese-related EVs may have the potential to modulate fibroblast phenotype in BC. Finally, cytokine arrays revealed that treatment of CF with OW/Ob EVs was associated with an enhanced release of Fibroblast Growth Factor 19 and Cystatin C, factors that are closely related to BC growth and development. In conclusion, our data provide first evidence for the functional importance of EVs isolated from obese women in impacting tumor-stroma cross-talk and drive BC progression. Since obesity and its pathophysiological sequelae are on the rise, this new knowledge may help to identify specific biomarkers and innovative targets (i.e. FGF-19, and Cystatin C) that may allow a personalized management of patients affected by BC and obesity. Citation Format: Ines Barone, Piercarlo Del Console, Felice Maria Accattatis, Luca Gelsomino, Giuseppina Augimeri, Ennio Avolio, Sebastiano Andò, Daniela Bonofiglio, Cinzia Giordano, Stefania Catalano. Impact of Circulating Extracellular Vesicles derived from Obese Women on Pro-Tumor Functions of Stromal Fibroblasts in Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-24-11.

Sensitivity of magnetic resonance elastography to extracellular matrix and cell motility in human prostate cancer cell line-derived xenograft models

Prostate cancer (PCa) is a significant health problem in the male population of the Western world. Magnetic resonance elastography (MRE), an emerging medical imaging technique sensitive to mechanical properties of biological tissues, detects PCa based on abnormally high stiffness and viscosity values. Yet, the origin of these changes in tissue properties and how they correlate with histopathological markers and tumor aggressiveness are largely unknown, hindering the use of tumor biomechanical properties for establishing a noninvasive PCa staging system.To infer the contributions of extracellular matrix (ECM) components and cell motility, we investigated fresh tissue specimens from two PCa xenograft mouse models, PC3 and LNCaP, using magnetic resonance elastography (MRE), diffusion-weighted imaging (DWI), quantitative histology, and nuclear shape analysis. Increased tumor stiffness and impaired water diffusion were observed to be associated with collagen and elastin accumulation and decreased cell motility. Overall, LNCaP, while more representative of clinical PCa than PC3, accumulated fewer ECM components, induced less restriction of water diffusion, and exhibited increased cell motility, resulting in overall softer and less viscous properties. Taken together, our results suggest that prostate tumor stiffness increases with ECM accumulation and cell adhesion - characteristics that influence critical biological processes of cancer development.MRE paired with DWI provides a powerful set of imaging markers that can potentially predict prostate tumor development from benign masses to aggressive malignancies in patients. Statement of significanceXenograft models of human prostate tumor cell lines, allowing correlation of microstructure-sensitive biophysical imaging parameters with quantitative histological methods, can be investigated to identify hallmarks of cancer.

Abstract 1569: Keratin X promotes cell metastasis and sorafenib resistance via the AMPKα/Snail axis in hepatocellular carcinoma

Abstract A great majority of liver cancers are developed from cirrhotic livers. The key molecules involved in cirrhosis-mediated hepatocarcinogenesis have not been clearly defined. Understanding the oncogenic pathways and their associations with cancer growth, metastasis and drug resistance may help scientists devise new effective therapeutic agents. In the present study, we identified the intermediate filament-forming protein keratin X (KRTX) as a key factor in cirrhosis-mediated hepatocarcinogenesis. KRTX was highly expressed in HCC tissues and correlated with poor survival outcomes. Experimental verification revealed that overexpression of KRTX enhanced cell growth, tumor cell metastasis, glycolysis and sorafenib resistance. Conversely, knockdown of KRTX led to opposite effects. Mechanistically, KRTX inhibited AMPKα phosphorylation, thereby enhancing Snail protein stability. Additionally, TGFβ1 positively regulated KRTX expression, resulting in a KRTX/AMPKα (Thr172)/Snail axis-mediated increase in cell motility. Treating with 2-deoxyglucose reversed the KRTX-induced metastasis and sorafenib resistance. In clinic, KRTX expression is positively correlated with Snail overexpression and high KRTX/Snail expression had poor prognosis in HCC patients. Our data revealed a signaling pathway from TGFβ1, KRTX, through p-AMPKα (Thr172) to Snail. Targeting KRTX and its pathway may be effective for treating patients with metastatic HCC. Citation Format: Yang-Hsiang Lin, Chau-Ting Yeh. Keratin X promotes cell metastasis and sorafenib resistance via the AMPKα/Snail axis in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1569.

Abstract 5193: Molecular evolution of chemoresistance acquisition and predictive insights into the progression of bladder cancer

Abstract Cancer heterogeneity arises from cellular features, suggesting that distinct molecular drivers may be latent within cancers diagnosed at different clinicopathological stages. We thoroughly assessed phenotypic traits and molecular alterations linked to chemoresistance and constructed chemoresistant bladder cancer cell lines representing the stepwise transformation. Model cell lines (5637GRCs, gemcitabine-resistant cells) with stepwise gemcitabine resistance representing early, intermediate, and late resistance phases were developed from non-muscle-invasive bladder cancer (NMIBC) cells. Notably, an increase in cell motility was observed at a relatively early phase. The results from the time-course analysis of molecular evolution showed changes in focal adhesion kinase signaling, PI3K-Akt signaling, and TGF-β signaling pathways during the phase of increasing cell motility. As chemoresistance increased, the levels of genes related to differentiation and MAPK signaling gradually increased. A 63-gene chemoresistance-motility (CrM) signature was constructed and weighted according to cell motility, and a strong correlation was observed between cancer metastasis and drug resistance; the signature also showed prognostic relevance in patients with NMIBC. This study affords a significant understanding of the molecular evolution of chemoresistance acquisition and enables prediction of cancer progression during chemotherapy treatment. Moreover, it provides insights into the progression of cells through all chemoresistance stages from NMIBC to MIBC. Therefore, this study proposes the feasibility of utilizing biomarkers correlated with cancer motility to predict cancer progression in the early phase of chemotherapeutic intervention in patients with non-muscle-invasive bladder cancer. Citation Format: Gi-Eun Yang, Jae-Jun Kim, Tae Hwan Shin, Sun-Hee Leem. Molecular evolution of chemoresistance acquisition and predictive insights into the progression of bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5193.

Abstract 5879: Role of the inner mitochondrial membrane protein (Mic60) in MAPKi-resistant melanoma

Abstract Introduction: Metastatic melanoma is one of the most aggressive cancers, despite recent improvements in therapy. The rising melanoma incidence and mortality, along with its high propensity for metastasis highlights the urgency to find more effective therapeutic targets. The efficacy of targeted MAPK signaling pathway inhibitors (MAPKi) in metastatic melanoma therapy is limited by the development of resistance mechanisms that result in disease relapse. This situation necessitates alternative treatments for melanoma patients who develop resistance to targeted therapy. We have recently found out that there exists a group of human tumors that express lower levels of Mic60, a mitochondrial structural protein also known as mitofilin or inner membrane mitochondrial protein (IMMT). In a model of prostate cancer, we showed that Mic60-low tumors have lower mitochondrial fitness, but increased cell motility, invasion, and propensity to metastasize. However, a potential differential expression of Mic60 in melanoma has not been investigated and whether reduced mitochondrial fitness in Mic60-low tumors can expose new therapeutic vulnerabilities in combination with targeted therapies has not been determined. Experimental Procedures: We analyzed melanoma-specific TMA for differential expression of Mic60 in tumor vs. adjacent normal tissue by IHC. Differential mRNA expression levels were examined by single-cell RNA-Seq and quantified by bioinformatics analysis. Differential therapeutic vulnerabilities of Mic60-low melanoma cell lines to mitochondrial-targeted small molecule Hsp90 inhibitor, Gamitrinib, were assessed for cell death induction and mitochondrial dysfunction. Results: We identified subsets of melanoma patients with constitutively reduced or outright undetectable expression of Mic60, in vivo. By single-cell RNA-Seq, Mic60-low melanomas were characterized by reduced oxidative phosphorylation and decreased ATP production, slower cell cycle progression but paradoxically increased cell motility and invasion. Loss of Mic60 exposed new, actionable therapeutic vulnerabilities, and the combination of Gamitrinib plus MAPKi potently induced mitochondrial cell death in MAPKi-resistant melanoma cell lines. Conclusion: Mic60 is heterogeneously expressed and often reduced in melanoma. Although this is associated with increased cell invasion and metastatic propensity, the combination of Gamitrinib plus MAPKi restored mitochondrial cell death in therapy-resistant, Mic60-low melanoma cells. Citation Format: Jagadish C. Ghosh, Segundo Del Aguila, Haiyin Li, Jessie Villanueva, Dario C. Altieri. Role of the inner mitochondrial membrane protein (Mic60) in MAPKi-resistant melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5879.

PLK1 and its substrate MISP facilitate intrahepatic cholangiocarcinoma progression by promoting lymphatic invasion and impairing E-cadherin adherens junctions.

Intrahepatic cholangiocarcinoma (iCCA) is a subtype of CCA and has a high mortality rate and a relatively poor prognosis. However, studies focusing on increased cell motility and loss of epithelial integrity during iCCA progression remain relatively scarce. We collected seven fresh tumor samples from four patients to perform RNA sequencing (RNA-seq) and assay for transposase-accessible chromatin using sequencing (ATAC-seq) to determine the transcriptome profile and chromatin accessibility of iCCA. The increased expression of cell cycle regulators, including PLK1 and its substrate MISP, was identified. Ninety-one iCCA patients were used to validate the clinical significance of PLK1 and MISP. The upregulation of PLK1 and MISP was determined in iCCA tissues. Increased expression of PLK1 and MISP was significantly correlated with tumor number, N stage, and lymphatic invasion in an iCCA cohort. Knockdown of PLK1 or MISP reduced trans-lymphatic endothelial migration and wound healing and affected focal adhesions in vitro. In cell‒cell junctions, MISP localized to adherens junctions and suppressed E-cadherin dimerization. PLK1 disrupted adherens junctions in a myosin-dependent manner. Furthermore, PLK1 and MISP promoted cell proliferation in vitro and tumorigenesis in vivo. In iCCA, PLK1 and MISP promote aggressiveness by increasing lymphatic invasion, tumor growth, and motility through the repression of E-cadherin adherens junctions.

The p110α/ΔNp63α complex mutations in triple-negative breast cancer: Potential targets for transcriptional-based therapies.

Hotspot mutations occurring in the p110α domain of the PIK3CA gene, specifically p110αH1047R/L increase tumor metastasis and cell motility in triple-negative breast cancer (TNBC). These mutations also affect the transcriptional regulation of ΔNp63α, a significant isoform of the p53 protein involved in cancer progression. This study attempts to investigate the transcriptional impact of p110αH1047R/L mutations on the PIK3CA/ΔNp63α complex in TNBC carcinogenesis. We performed site-directed mutagenesis to introduce p110αH1047R/L mutations and evaluated their oncogenic effects on the growth, invasion, migration, and apoptosis of three different TNBC cell lines in vitro. We investigated the impact of these mutations on the p110α/ΔNp63α complex and downstream transcriptional signaling pathways at the gene and protein levels. Additionally, we used bioinformatics techniques such as molecular dynamics simulations and protein-protein docking to gain insight into the stability and structural changes induced by the p110αH1047R/L mutations in the p110α/ΔNp63α complex and downstream signaling pathway. The presence of PIK3CA oncogenic hotspot mutations in the p110α/ΔNp63α complex led to increased scattering of TNBC cells during growth, migration, and invasion. Our in vitro mutagenesis assay showed that the p110αH1047R/L mutations activated the PI3K-Akt-mTOR and tyrosine kinase receptor pathways, resulting in increased cell proliferation, invasion, and apoptosis in TNBC cells. These mutations decreased the repressing effect of ΔNp63α on the p110α kinase domain, leading to the enhancement of downstream signaling pathways of PI3K and tyrosine kinase receptors and oncogenic transformation in TNBC. Additionally, our findings suggest that the physical interaction between the DNA binding domain of ΔNp63α and the kinase domain of p110α may be partially impaired, potentially leading to alterations in the conformation of the p110α/ΔNp63α complex. Our findings suggest that targeting the p110αH1047R/L mutations in TNBC could be a promising strategy for developing transcriptional-based therapies. Restoring the interaction between ΔNp63α and the p110α kinase domain, which is disrupted by these mutations, may provide a new approach to treating TNBC.

Prognostic Value of Tumor Budding for Early Breast Cancer.

Tumor budding (TB) is a dynamic process associated with the epithelial-mesenchymal transition and a well-established prognostic biomarker for colorectal cancer. As part of the tumor microenvironment, tumor buds demonstrate increased cell motility and invasiveness. Current evidence demonstrates that high levels of TB correlate with disease progression and worst outcomes across different solid tumors. Our work aims to demonstrate the clinical applicability of TB analysis and its utility as a prognostic factor for patients with early breast cancer (EBC). Retrospective, single-center, observational study, enrolling patients with EBC diagnosed in a Portuguese hospital between 2014 and 2015. TB classification was performed according to the International Tumor Budding Conference 2016 guidelines. A statistically significant relation was found between higher TB score and aggressive clinicopathological features (angiolymphatic/perineural invasion-p < 0.001; tumor size-p = 0.012; nuclear grading-p < 0.001; and Ki-67 index-p = 0.011), higher number of relapses (p < 0.001), and short disease-free survival (DFS) (p < 0.001). We demonstrate that high TB correlates with shorter DFS and aggressive clinicopathological features used in daily practice to decide on the benefit of chemotherapy for EBC. TB represents a needed prognostic biomarker for EBC, comprising a new factor to be considered in the adjuvant decision-making process by identifying patients at a high risk of relapse and with higher benefit on treatment intensification. Clinical trials incorporating TB are needed to validate its prognostic impact.

Polo-like kinase-1 mediates hepatitis C virus-induced cell migration, a drug target for liver cancer.

Polo-like kinase 1 (PLK1) is a regulator of cell mitosis and cytoskeletal dynamics. PLK1 overexpression in liver cancer is associated with tumour progression, metastasis, and vascular invasion. Hepatitis C virus (HCV) NS5A protein stimulates PLK1-mediated phosphorylation of host proteins, so we hypothesised that HCV-PLK1 interactions might be a mechanism for HCV-induced liver cancer. We used a HCV cell-culture model (Jc1) to investigate the effects of virus infection on the cytoskeleton. In HCV-infected cells, a novel posttranslational modification in β-actin was observed with phosphorylation at Ser239. Using in silico and in vitro approaches, we identified PLK1 as the mediating kinase. In functional experiments with a phosphomimetic mutant form of β-actin, Ser239 phosphorylation influences β-actin polymerization and distribution, resulting in increased cell motility. The changes were prevented by treating cells with the PLK1 inhibitor volasertib. In HCV-infected hepatocytes, increased cell motility contributes to cancer cell migration, invasion, and metastasis. PLK1 is an important mediator of these effects and early treatment with PLK1 inhibitors may prevent or reduce HCC progression, particularly in people with HCV-induced HCC.

Characterization of Breast Cancer Aggressiveness by Cell Mechanics.

In healthy tissues, cells are in mechanical homeostasis. During cancer progression, this equilibrium is disrupted. Cancer cells alter their mechanical phenotype to a softer and more fluid-like one than that of healthy cells. This is connected to cytoskeletal remodeling, changed adhesion properties, faster cell proliferation and increased cell motility. In this work, we investigated the mechanical properties of breast cancer cells representative of different breast cancer subtypes, using MCF-7, tamoxifen-resistant MCF-7, MCF10A and MDA-MB-231 cells. We derived viscoelastic properties from atomic force microscopy force spectroscopy measurements and showed that the mechanical properties of the cells are associated with cancer cell malignancy. MCF10A are the stiffest and least fluid-like cells, while tamoxifen-resistant MCF-7 cells are the softest ones. MCF-7 and MDA-MB-231 show an intermediate mechanical phenotype. Confocal fluorescence microscopy on cytoskeletal elements shows differences in actin network organization, as well as changes in focal adhesion localization. These findings provide further evidence of distinct changes in the mechanical properties of cancer cells compared to healthy cells and add to the present understanding of the complex alterations involved in tumorigenesis.

USP22 promotes aspirin-induced trophoblast cell proliferation as well as migration via Wnt/β-catenin pathway in preeclampsia

Purpose: To investigate the involvement of ubiquitin-specific peptidase 22 (USP22) in the pathogenesis of preeclampsia (PE), and the potential mechanism of action.&#x0D; Methods: To investigate the role of USP22 in preeclampsia, immunoblot assay as well as quantitative real-time polymerase chain reaction (qRT-PCR) were conducted to determine USP22 expression levels in placental tissues from both the control (non-preeclampsia normal) and the PE cases. Furthermore, cell counting kit-8 as well as EdU assays were performed to assess the impact of USP22 on the viability of HTR-8/Svneo and TEV-1 cells. Furthermore, wound closure and Transwell assays were used to examine the effect of USP22 on cell motility, while tube formation assay was used to determine the effect of USP22 on the angiogenesis of trophoblast cells. Finally, the effect of USP22 on Wnt/β-catenin pathway in HTR-8/Svneo and TEV-1 human trophoblast cells was evaluated by immunoblot analysis.&#x0D; Results: USP22 expression was significantly reduced in PE placental tissue compared to control tissues. In addition, USP22 promoted trophoblast cell proliferation, increased cell motility as well as enhanced angiogenesis capacity. USP22 regulated the proliferation as well as migration of trophoblast cells via Wnt/β-catenin pathway. Notably, USP22 enhanced cell proliferation and migration in aspirininduced PE.&#x0D; Conclusion: USP22 plays a crucial role in inhibiting trophoblast cell growth by regulating Wnt/β-catenin pathway. Therefore, targeting USP22 may hold promise for the treatment of PE.

Src stimulates Abl-dependent phosphorylation of the guanine exchange factor Net1A to promote its cytosolic localization and cell motility

The neuroepithelial cell transforming gene 1 (Net1) is a guanine nucleotide exchange factor for the small GTPase RhoA that promotes cancer cell motility and metastasis. Two isoforms of Net1 exist, Net1 and Net1A, both of which are sequestered in the nucleus in quiescent cells to prevent aberrant RhoA activation. Many cell motility stimuli drive cytosolic relocalization of Net1A, but mechanisms controlling this event are not fully understood. Here, we demonstrate that epithelial growth factor stimulates protein kinase Src- and Abl1-dependent phosphorylation of Net1A to promote its cytosolic localization. We show that Abl1 efficiently phosphorylates Net1A on Y373, and that phenylalanine substitution of Y373 prevents Net1A cytosolic localization. Furthermore, we found that Abl1-driven cytosolic localization of Net1A does not require S52, which is a phosphorylation site of a different kinase, c-Jun N-terminal kinase, that inhibits nuclear import of Net1A. However, we did find that MKK7-stimulated cytosolic localization of Net1A does require Y373. We also demonstrate that aspartate substitution at Y373 is sufficient to promote Net1A cytosolic accumulation, and expression of Net1A Y373D potentiates epithelial growth factor-stimulated RhoA activation, downstream myosin light chain 2 phosphorylation, and F-actin accumulation. Moreover, we show that expression of Net1A Y373D in breast cancer cells also significantly increases cell motility and Matrigel invasion. Finally, we show that Net1A is required for Abl1-stimulated cell motility, which is rescued by expression of Net1A Y373D, but not Net1A Y373F. Taken together, this work demonstrates a novel mechanism controlling Net1A subcellular localization to regulate RhoA-dependent cell motility and invasion.

Visualization of Cellular Membranes in 2D and 3D Conditions Using a New Fluorescent Dithienothiophene S,S-Dioxide Derivative.

Cellular membranes play a key role in cell communication with the extracellular environment and neighboring cells. Any changes, including their composition, packing, physicochemical properties and formation of membrane protrusions may affect cells feature. Despite its great importance, tracking membrane changes in living cells is still a challenge. For investigation of processes related to tissue regeneration and cancer metastasis, such as the induction of epithelial-mesenchymal transition, increased cell motility, and blebbing, the possibility to conduct prolonged observation of membrane changes is beneficial, albeit difficult. A particular challenge is conducting this type of research under detachment conditions. In the current manuscript, a new dithienothiophene S,S-dioxide (DTTDO) derivative is presented as an effective dye for staining the membranes of living cells. The synthetic procedures, physicochemical properties, and biological activity of the new compound are presented herein. In addition to the labeling of the membranes in a monolayer culture, its usefulness for visualization of membranes under detachment conditions is also demonstrated. Obtained data have proven that a new DTTDO derivative may be used to stain membranes in various types of experimental procedures, from traditional 2D cell cultures to unanchored conditions. Moreover, due to the specific optical properties, the background signal is reduced and, thus, observation may be performed without washing.

Effects of Omeprazole on Recurrent Clostridioides difficile Infection Caused by ST81 Strains and Their Potential Mechanisms.

Clostridioides difficile infection (CDI) is associated with high recurrence rates that have substantial effects on patients' quality of life. To investigate the risk factors and potential mechanisms contributing to recurrent CDI (rCDI), a total of 243 cases were enrolled in this study. The history of omeprazole (OME) medication and ST81 strain infection were considered the two independent risks with the highest odds ratios in rCDI. In the presence of OME, we detected concentration-dependent increases in the MIC values of fluoroquinolone antibiotics against ST81 strains. Mechanically, OME facilitated ST81 strain sporulation and spore germination by blocking the pathway of purine metabolism and also promoted an increase in cell motility and toxin production by turning the flagellar switch to the ON state. In conclusion, OME affects several biological processes during C difficile growth, which have fundamental impacts on the development of rCDI caused by ST81 strains. Programmed OME administration and stringent surveillance of the emerging ST81 genotype are matters of considerable urgency and significance in rCDI prevention.