A high expression ratio of RhoA/RhoB is associated with the migratory and invasive properties of basal-like Breast Tumors

Tissue-dependent mechanosensing by cells derived from human tumors

Alterations of the extracellular matrix (ECM), including both mechanical (such as stiffening of the ECM) and chemical (such as variation of adhesion proteins and deposition of hyaluronic acid (HA)) changes, in malignant tissues have been shown to mediate tumor progression. To survey how cells from different tissue types respond to various changes in ECM mechanics and composition, we measured physical characteristics (adherent area, shape, cell stiffness, and cell speed) of 25 cancer and 5 non-tumorigenic cell lines on 7 different substrate conditions. Our results indicate substantial heterogeneity in how cell mechanics changes within and across tissue types in response to mechanosensitive and chemosensitive changes in ECM. The analysis also underscores the role of HA in ECM with some cell lines showing changes in cell mechanics in response to presence of HA in soft substrate that are similar to those observed on stiff substrate. This pan-cancer investigation also highlights the importance of tissue-type and cell line specificity for inferences made based on comparison between physical properties of cancer and normal cells. Lastly, using unsupervised machine learning, we identify phenotypic classes that characterize the physical plasticity, i.e. the distribution of physical feature values attainable, of a particular cell type in response to different ECM-based conditions.

Analysis of chromatin accessibility in peripheral blood mononuclear cells from patients with early-stage breast cancer

Objective: This study was aimed at exploring a specific open region of chromatin in the peripheral blood mononuclear cells (PBMCs) of patients with breast cancer and evaluating its feasibility as a biomarker for diagnosing and predicting breast cancer prognosis. Methods: We obtained PBMCs from breast cancer patients and healthy people for the assay for transposase-accessible chromatin (ATAC) sequencing (n = 3) and obtained the GSE27562 chip sequencing data for secondary analyses. Through bioinformatics analysis, we mined the pattern changes for chromatin accessibility in the PBMCs of breast cancer patients. Results: A total of 1,906 differentially accessible regions (DARs) and 1,632 differentially expressed genes (DEGs) were identified via ATAC sequencing. The upregulated DEGs in the disease group were mainly distributed in the cells, organelles, and cell-intima-related structures and were mainly responsible for biological functions such as cell nitrogen complex metabolism, macromolecular metabolism, and cell communication, in addition to functions such as nucleic acid binding, enzyme binding, hydrolase reaction, and transferase activity. Combined with microarray data analysis, the following set of nine DEGs showed intersection between the ATAC and microarray data: JUN, MSL2, CDC42, TRIB1, SERTAD3, RAB14, RHOB, RAB40B, and PRKDC. HOMER predicted and identified five transcription factors that could potentially bind to these peak sites, namely NFY, Sp 2, GFY, NRF, and ELK 1. Conclusion: Chromatin accessibility analysis of the PBMCs from patients with early-stage breast cancer underscores its potential as a significant avenue for biomarker discovery in breast cancer diagnostics and treatment. By screening the transcription factors and DEGs related to breast cancer, this study provides a comprehensive theoretical foundation that is expected to guide future clinical applications and therapeutic developments.

Transcriptomics Studies Reveal Functions of Transglutaminase 2 in Breast Cancer Cells Using Membrane Permeable and Impermeable Inhibitors

Transglutaminase 2 (TG2) performs many functions both under physiological and pathological conditions. In cancer, its expression is associated with aggressiveness, propensity to epithelial-mesenchymal transition, and metastasis. Since TG2 performs key functions both outside and inside the cell, using inhibitors with different membrane permeability we analyzed the changes in the transcriptome induced in two triple-negative cell lines (MDA-MB-436 and MDA-MB-231) with aggressive features. By characterizing pathways and gene networks, we were able to define the effects of TG2 inhibitors (AA9, membrane-permeable, and NCEG2, impermeable) in relation to the roles of the enzyme in the intra- and extracellular space within the context of breast cancer. The deregulated genes revealed p53 and integrin signaling to be the common pathways with some genes showing opposite changes in expression. In MDA-MB-436, AA9 induced apoptosis, modulated cadherin, Wnt, gastrin and cholecystokinin receptors (CCKR) mediated signaling, with RHOB and GNG2 playing significant roles, and affected the Warburg effect by decreasing glycolytic enzymes. In MDA-MB-231 cells, AA9 strongly impacted HIF-mediated hypoxia, including AKT and mTOR pathway. These effects suggest an anti-tumor activity by blocking intracellular TG2 functions. Conversely, the use of NCEG2 stimulated the expression of ATP synthase and proteins involved in DNA replication, indicating a potential promotion of cell proliferation through inhibition of extracellular TG2. To effectively utilize these molecules as an anti-tumor strategy, an appropriate delivery system should be evaluated to target specific functions and avoid adverse effects. Additionally, considering combinations with other pathway modulators is crucial.

CDC45 promotes the stemness and metastasis in lung adenocarcinoma by affecting the cell cycle

OBJECTIVE

This study aimed to assess the functions of cell division cycle protein 45 (CDC45) in Non-small cell lung cancer (NSCLC) cancer and its effects on stemness and metastasis.

METHODS

Firstly, differentially expressed genes related to lung cancer metastasis and stemness were screened by differential analysis and lasso regression. Then, in vitro, experiments such as colony formation assay, scratch assay, and transwell assay were conducted to evaluate the impact of CDC45 knockdown on the proliferation and migration abilities of lung cancer cells. Western blotting was used to measure the expression levels of related proteins and investigate the regulation of CDC45 on the cell cycle. Finally, in vivo model with subcutaneous injection of lung cancer cells was performed to verify the effect of CDC45 on tumor growth.

RESULTS

This study identified CDC45 as a key gene potentially influencing tumor stemness and lymph node metastasis. Knockdown of CDC45 not only suppressed the proliferation and migration abilities of lung cancer cells but also caused cell cycle arrest at the G2/M phase. Further analysis revealed a negative correlation between CDC45 and cell cycle-related proteins, stemness-related markers, and tumor mutations. Mouse experiments confirmed that CDC45 knockdown inhibited tumor growth.

CONCLUSION

As a novel regulator of stemness, CDC45 plays a role in regulating lung cancer cell proliferation, migration, and cell cycle. Therefore, CDC45 may serve as a potential target for lung cancer treatment and provide a reference for further mechanistic research and therapeutic development.

Scutellaria barbata D.Don extract regulates Ezrin-mediated triple negative breast cancer progress via suppressing the RhoA /ROCK1 signaling

Background

Triple-negative breast cancer (TNBC) lacks effective therapeutic targets. Scutellaria barbata D.Don (SB) has been revealed to have anti-breast cancer (BC) effect, but the effect of SB extract in TNBC is still unclear. Herein, this research delves into the underlying mechanism.

Methods

SB was extracted by solvent extraction, and the main components were identified using an Agilent 6,520 HPLC-Chip/Q-TOF (Chip/Q-TOF) MS system. In vitro cell experiments were conducted. The effects of SB extract alone, SB extract plus EGF, GSK alone, GSK plus Ezrin overexpression, or SB extract plus Ezrin overexpression on cell viability, invasion, migration, and apoptosis were examined by cell function experiments. The apoptosis- and RhoA/ROCK1 pathway-related protein levels were analyzed by western blot assay.

Results

Mass spectrometry analysis exhibited that SB extract mainly contains long-chain fatty acids and ursolic acid. SB extract mitigated TNBC cell biological phenotypes, apoptosis- and RhoA/ROCK1 pathway-related marker expressions, which were reversed by EGF. The further results found that GSK obviously weakens TNBC cell biological behaviors, apoptosis- and RhoA/ROCK1 signaling-related protein levels, while oe-Ezrin treatment reverses the effect of GSK on TNBC cells. Moreover, SB extract regulated Ezrin-mediated function of TNBC cells by impeding the RhoA/ROCK1 pathway.

Conclusion

Our findings demonstrated that SB extract regulated Ezrin-mediated proliferation, migration, invasion, and apoptosis of TNBC cells via suppressing the RhoA /ROCK1 signaling. Our results offer the experimental foundation for further investigation of the anti-cancer role of SB in TNBC cells.

Highlights

SB extract inhibits the biological phenotypes of TNBC cells.SB extract inhibits the biological behaviors of TNBC cells through the RhoA/ROCK1 pathway.SB extract modulates Ezrin-mediated TNBC cell proliferation, migration, invasion, and apoptosis via restraining the RhoA/ROCK1 signaling.

Clinically Expired Platelet Concentrates as a Source of Extracellular Vesicles for Targeted Anti-Cancer Drug Delivery

The short shelf life of platelet concentrates (PC) of up to 5–7 days leads to higher wastage due to expiry. To address this massive financial burden on the healthcare system, alternative applications for expired PC have emerged in recent years. Engineered nanocarriers functionalized with platelet membranes have shown excellent targeting abilities for tumor cells owing to their platelet membrane proteins. Nevertheless, synthetic drug delivery strategies have significant drawbacks that platelet-derived extracellular vesicles (pEV) can overcome. We investigated, for the first time, the use of pEV as a carrier of the anti-breast cancer drug paclitaxel, considering it as an appealing alternative to improve the therapeutic potential of expired PC. The pEV released during PC storage showed a typical EV size distribution profile (100–300 nm) with a cup-shaped morphology. Paclitaxel-loaded pEV showed significant anti-cancer effects in vitro, as demonstrated by their anti-migratory (>30%), anti-angiogenic (>30%), and anti-invasive (>70%) properties in distinct cells found in the breast tumor microenvironment. We provide evidence for a novel application for expired PC by suggesting that the field of tumor treatment research may be broadened by the use of natural carriers.

Relationship between the expression of ARHGAP25 and RhoA in non-small cell lung cancer and vasculogenic mimicry

Background

Vasculogenic mimicry (VM) is a recently identified pattern of blood supply to tumor tissue. It has long been considered a functional element in the metastasis and prognosis of malignant tumors. Both Rho GTPase-activating protein 25 (ARHGAP25) and Ras homolog family member A (RhoA) are effective predictors of tumor metastasis. In this study, we examined the expression levels of ARHGAP25 and RhoA and the structure of VM in non-small cell lung cancer (NSCLC). At the same time, we used cytology-related experiments to explore the effect of ARHGAP25 on the migration ability of tumor cells. Furthermore, we analyzed the interaction between the three factors and their association with clinicopathological characteristics and the five-year survival time in patients using statistical tools.

Methods

A total of 130 well-preserved NSCLC and associated paracancerous tumor-free tissues were obtained. Cell colony formation, wound healing, and cytoskeleton staining assays were used to analyze the effect of ARHGAP25 on the proliferation and migration ability of NSCLC cells. Immunohistochemical staining was used to determine the positivity rates of ARHGAP25, RhoA, and VM. Statistical software was used to examine the relationships between the three factors and clinical case characteristics, overall survival, and disease-free survival.

Results

Cell colony formation, wound healing, and cytoskeleton staining assays confirmed that ARHGAP25 expression affects the proliferation and migratory abilities of NSCLC cells. ARHGAP25 positivity rates in NSCLC and paracancerous tumor-free tissues were 48.5% and 63.1%, respectively, whereas RhoA positivity rates were 62.3% and 18.5%, respectively. ARHGAP25 had a negative relationship with RhoA and VM, whereas RhoA and VM had a positive relationship (P < 0.05). ARHGAP25, RhoA, and VM affected the prognosis of patients with NSCLC (P < 0.05) according to Kaplan–Meier of survival time and Cox regression analyses. Furthermore, lowering ARHGAP25 expression increased NSCLC cell proliferation and migration.

Conclusions

ARHGAP25 and RhoA expression is associated with VM and may be of potential value in predicting tumor metastasis, prognosis, and targeted therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02179-5.

Long Noncoding RNA FBXL19-AS1-Mediated Ulcerative Colitis-Associated Intestinal Epithelial Barrier Defect

BACKGROUND

This study commenced to uncover the role of long non-coding RNA FBXL19 antisense RNA 1 (FBXL19-AS1) in the development of ulcerative colitis (UC) and its possible mechanism.

METHODS

FBXL19-AS1 expression in the colonic sigmoid mucosa of UC patients was detected. A colitis model was induced in mice using 5% dextran sodium sulfate. Hematoxylin-eosin staining was performed for histopathological examination. Apoptosis was detected by Tunel staining and tissue fibrosis was detected by immunohistochemistry. Also, intestinal permeability was examined. The concentrations of inflammatory factors IL-1β and IL-18 were detected by enzyme-linked immunosorbent assay. The relationship between FBXL19-AS1, miR-339-3p and RHOB was verified by RNA immunoprecipitation assay and dual luciferase reporter assay.

RESULTS

The expression of FBXL19-AS1 was increased in dextran sodium sulfate (DSS)-induced colitis mouse model. FBXL19-AS1 interference or miR-339-3p overexpression inhibited DSS-induced colonic epithelial cell apoptosis and inflammatory response, and improved intestinal epithelial barrier defects, thereby ameliorating DSS-induced colitis injury in mice. FBXL19-AS1 sponged miR-339-3p while miR-339-3p targeted RHOB. Overexpression of RHOB reversed the protective effect of inhibition of FBXL19-AS1 on DSS-induced colitis in mice.

CONCLUSION

FBXL19-AS1 reduces miR-339-3p-mediated targeting of RHOB and aggravates intestinal epithelial barrier defect in DSS-induced colitis in mice.

EphA4 regulates white matter remyelination after ischemic stroke through Ephexin-1/RhoA/ROCK signaling pathway

Ischemic stroke, which accounts for nearly 80% of all strokes, leads to white matter injury and neurobehavioral dysfunction, but relevant therapies to inhibit demyelination or promote remyelination after white matter injury are still unavailable. In this study, the middle cerebral artery occlusion/reperfusion (MCAO/R) in vivo and oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro were used to establish the ischemic models. We found that Eph receptor A4 (EphA4) had no effect on the apoptosis of oligodendrocytes using TUNEL staining. In contrast, EphA4 promoted proliferation of oligodendrocyte precursor cells (OPCs), but reduced the numbers of mature oligodendrocytes and the levels of myelin-associated proteins (MAG, MOG, and MBP) in the process of remyelination in ischemic models in vivo and in vitro as determined using PDGFRα-EphA4-shRNA and LV-EphA4 treatments. Notably, conditional knockout of EphA4 in OPCs (EphA4^fl/fl  + AAV-PDGFRα-Cre) improved the levels of myelin-associated proteins and functional recovery following ischemic stroke. In addition, regulation of remyelination by EphA4 was mediated by the Ephexin-1/RhoA/ROCK signaling pathway. Therefore, EphA4 did not affect oligodendrocyte (OL) apoptosis but regulated white matter remyelination after ischemic stroke through the Ephexin-1/RhoA/ROCK signaling pathway. EphA4 may provide a novel and effective therapeutic target in clinical practice of ischemic stroke.

RHO GTPase-Related Long Noncoding RNAs in Human Cancers

RHO GTPases are critical signal transducers that regulate cell adhesion, polarity, and migration through multiple signaling pathways. While all these cellular processes are crucial for the maintenance of normal cell homeostasis, disturbances in RHO GTPase-associated signaling pathways contribute to different human diseases, including many malignancies. Several members of the RHO GTPase family are frequently upregulated in human tumors. Abnormal gene regulation confirms the pivotal role of lncRNAs as critical gene regulators, and thus, they could potentially act as oncogenes or tumor suppressors. lncRNAs most likely act as sponges for miRNAs, which are known to be dysregulated in various cancers. In this regard, the significant role of miRNAs targeting RHO GTPases supports the view that the aberrant expression of lncRNAs may reciprocally change the intensity of RHO GTPase-associated signaling pathways. In this review article, we summarize recent advances in lncRNA research, with a specific focus on their sponge effects on RHO GTPase-targeting miRNAs to crucially mediate gene expression in different cancer cell types and tissues. We will focus in particular on five members of the RHO GTPase family, including RHOA, RHOB, RHOC, RAC1, and CDC42, to illustrate the role of lncRNAs in cancer progression. A deeper understanding of the widespread dysregulation of lncRNAs is of fundamental importance for confirmation of their contribution to RHO GTPase-dependent carcinogenesis.