Stabilizing vimentin phosphorylation inhibits stem-like cell properties and metastasis of hybrid epithelial/mesenchymal carcinomas

ADH1B regulates tumor stemness by activating the cAMP/PKA/CREB1 signaling axis to inhibit recurrence and metastasis of lung adenocarcinoma

Lung cancer remains the leading cause of cancer-related mortality, with non-small cell lung cancer (NSCLC) accounting for approximately 85 % of cases. Despite advancements in diagnostics and therapies, tumor metastasis and drug-resistant recurrence present significant clinical challenges. This study evaluates the prognostic role of ADH1B in lung adenocarcinoma (LUAD) metastasis and recurrence. Analysis of tissue samples from 46 LUAD patients revealed that lower ADH1B expression correlates with increased metastasis and poorer overall survival. Kaplan-Meier survival analysis demonstrated that elevated ADH1B levels are significantly associated with longer overall survival and recurrence-free survival. In vitro experiments indicated that ADH1B overexpression inhibits proliferation, migration, and invasion in A549 and H1299 cell lines. Additionally, ADH1B expression was negatively correlated with tumor stemness markers, indicating its role in suppressing stem cell characteristics. Mechanistically, ADH1B activates the cAMP/PKA/CREB1 signaling pathway, enhancing SOX1 expression and inhibiting the ERK pathway, which contributes to reduced tumor stemness. In vivo studies confirmed that ADH1B overexpression decreases stem cell populations and tumor growth in xenograft models. Our findings suggest that ADH1B functions as a critical regulator of LUAD progression, with its low expression acting as a marker of poor prognosis while promoting metastasis and tumor stemness. This research identifies ADH1B as a potential therapeutic target, offering novel strategies to address the challenges of metastasis and recurrence in LUAD.

Mechanical modulation of docetaxel-treated bladder cancer cells by various changes in cytoskeletal structures

Cytoskeleton targeting agents are a group of chemotherapeutics used in the therapy of many types of cancer, such as breast, prostate, lung, bladder cancer, and others. At the same time, the assessment of the rheological properties of cancer cells is a relevant marker of their metastatic potential and therapeutic efficacy. For these reasons, understanding the interaction between the actin microfilament (MFs) network, microtubules (MTs), and so-called intermediate filaments (IFs) is crucial for the use of the rheological properties of cells as biomechanical markers. The current work compares the rheological properties of bladder cancer cells T24 and 5637, which differ in cytoskeletal composition, treated with a low dose of docetaxel (DTX) - a microtubule targeting agent (MTA). AFM revealed that 5637 cells stiffen over time when exposed to DTX, whereas changes in rheological properties of T24 cells are less pronounced, and both softening and stiffening of cells are observed. From immunostaining and Western blot analysis, we found that in addition to changes in the content and organization of MTs, reorganization of MFs and vimentin IFs also occurs. We show that both cell and nucleus morphology changes after DTX treatment. DTX treatment decreases and increases the migratory potential of 5637 and T24 cells, respectively. The current work shows that vimentin IFs modulate the nanomechanics of bladder cancer cells.

Role of KLF5 in enhancing ovarian cancer stemness and PARPi resistance: mechanisms and therapeutic targeting

BACKGROUND

Ovarian cancer (OC) often presents at advanced stages with poor prognosis. Although poly(ADP-ribose) polymerase inhibitors (PARPi) offer clinical benefits, resistance remains a major challenge. This study investigates the role of KLF5 in regulating OC cell stemness and contributing to PARPi resistance.

METHODS

Gene expression analysis was conducted on OC cell lines and their PARPi-resistant counterparts. qRT-PCR and Western blotting assessed the expression levels of stemness markers and KLF5. IHC evaluated KLF5 expression in ovarian cancer tissue samples. Sphere formation and ALDH activity assays were used to evaluate stemness. Chromatin immunoprecipitation (ChIP) investigated KLF5's binding to the Vimentin promoter. The effects of the KLF5 inhibitor ML264 were tested in vitro using cell viability and apoptosis assays, and in vivo using a xenograft mouse model to evaluate tumor growth and response to PARPi treatment.

RESULTS

PARPi-resistant OC cells showed elevated stemness, indicated by increased SOX2, KLF4, Nanog, and OCT4 expression. KLF5 was significantly upregulated in these cells and linked to poor clinical outcomes. PARPi-resistant cells formed larger and more numerous spheres and had higher ALDH activity. KLF5 bound to the Vimentin promoter, upregulating its expression. Inhibition of KLF5 with ML264 reduced stemness features, decreased Vimentin expression, and resensitized resistant cells to PARPi. In vivo, ML264-treated mice with PARPi-resistant tumors exhibited reduced tumor growth and increased sensitivity to PARPi.

CONCLUSION

KLF5 enhances stemness and contributes to PARPi resistance in ovarian cancer through Vimentin regulation. Targeting KLF5 offers a promising therapeutic strategy to overcome resistance and improve patient outcomes.

Structure and function of vimentin in the generation and secretion of extracellular vimentin in response to inflammation

The canonical functions of vimentin in cell mechanics and migration have been recently expanded by the discovery of new roles for extracellular vimentin (ECV) in immune responses to infection, injury and cancer. In contrast with the predominantly filamentous form of intracellular vimentin, ECV exists largely as soluble oligomers. The release of ECV from intact cells is dependent on mechanisms that regulate the assembly and disassembly of intracellular vimentin, which are influenced by discrete post-translational modifications. In this review we highlight the processes that promote the conversion of intracellular and insoluble vimentin filaments to ECV and secretion mechanisms. Insights into the regulation of ECV release from stromal and immune cells could provide new diagnostic and therapeutic approaches for assessing and controlling inflammatory diseases.

tiRNA-Gly-GCC-002 promotes epithelial-mesenchymal transition and fibrosis in lupus nephritis via FKBP5-mediated activation of Smad

BACKGROUND AND PURPOSE

Renal interstitial fibrosis is a frequent pathological manifestation of lupus nephritis (LN). tRNA halves (tiRNAs) are acquired from tRNA-derived small non-coding RNAs (sncRNAs) and are associated with fibrosis. Our previous study indicated enhanced tiRNA-Gly-GCC-002 (tiRNA002) levels in kidneys were positively related to LN-related fibrosis. However, the precise molecular mechanism remains unclear.

EXPERIMENTAL APPROACH

The mimic and agomiR of tiRNA002 were introduced into tubular epithelial cells (TECs) and MRL/lpr mice by transfection. The levels of gene and protein expressions were quantified using real-time quantitative polymerase chain reaction (RT-qPCR), Western blot and immunofluorescence assays.

KEY RESULTS

In TECs treated with LN serum, as well as in the kidneys of MRL/lpr mice, high levels of tiRNA002 directly influenced the epithelial-mesenchymal transition (EMT) and extracellular matrix (ECM) deposition. Furthermore, tiRNA002 overexpression promoted EMT in TECs and accelerated renal interstitial fibrosis in MRL/lpr mice via Smad signalling. The target gene of tiRNA002, FKBP prolyl isomerase 5 (FKBP5), improved Smad signalling by interacting with phosphorylated Smad2/3. Silencing FKBP5 alleviated LN serum- or tiRNA002-mimic-induced EMT in TECs. In addition, FKBP5 overexpression reversed the tiRNA002 knockdown-mediated reduction of EMT and ECM accumulation.

CONCLUSIONS AND IMPLICATIONS

These findings indicated that tiRNA002 is markedly increased in LN, which facilitates renal fibrosis by promoting EMT via FKBP5-mediated Smad signalling. Therefore, targeting tiRNA002 may be an innovative approach to treat renal interstitial fibrosis in LN.

Design principles of regulatory networks underlying epithelial mesenchymal plasticity in cancer cells

Phenotypic plasticity is a hallmark of cancer and drives metastatic disease and drug resistance. The dynamics of epithelial mesenchymal plasticity is driven by complex interactions involving multiple feedback loops in underlying networks operating at multiple regulatory levels such as transcriptional and epigenetic. The past decade has witnessed a surge in systems level analysis of structural and dynamical traits of these networks. Here, we highlight the key insights elucidated from such efforts-a) multistability in gene regulatory networks and the co-existence of many hybrid phenotypes, thus enabling a landscape with multiple 'attractors', b) mutually antagonistic 'teams' of genes in these networks, shaping the rates of cell state transition in this landscape, and c) chromatin level changes that can alter the landscape, thus controlling reversibility of cell state transitions, allowing cellular memory in the context of epithelial mesenchymal plasticity in cancer cells. Such approaches, in close integration with high-throughput longitudinal data, have improved our understanding of the dynamics of cell state transitions implicated in tumor cell plasticity.

Withaferin-A induced vimentin S56 phosphorylation dissociates NEDD9 signaling loop to regress progressive metastatic melanoma into lung adenocarcinoma

Metastasis is complex and insidious type of disease involves multiple signaling nexus, which have implications in understanding disease pathogenesis. Treatment failure for metastatic cancer is frequently high due to aggressive adaptation of cancerous cells to invade to neighboring organs. Cytoskeleton intermediate filamentous protein Vimentin and scaffolding protein Neural precursor cell expressed Developmentally Down-regulated protein 9 (NEDD9) play a key role in metastatic events by regulating multiple metastatic events. Interaction between these proteins is necessary to promote metastatic progression. Withaferin A (WFA), a natural pharamacophore, known to target Vimentin to induce antitumor potential. However exact molecular mechanism still yet to be elucidated. We hypothesize, Vimentin-NEDD9 signaling nexus is necessary for metastatic progression and targeting this interwoven signaling loop with effective pharamacophore WFA halts metastatic progression of melanoma into lung. To elucidate the same, we carried out gene expression measurement through quantitative Reverses Transcription Polymerase Chain Reaction (qRT-PCR), Immunoblot and Immunohistochemistry. Assessment of interactive signaling by Co-immunoprecipitation, Immunofluorescence, Co-localization and Proximity ligation assay. Phosphorylation studies through transfection of phospho specific mutant constructs generated through site directed mutagenesis. WFA induced cellular behavioral changes by migration, invasion assays and Immunoblot analysis. The B16F10 induced mouse metastatic melanoma model to asses NEDD9-Vimentin expression and anti-metastasis induced by WFA. The results postulates, elevated levels and interaction between NEDD9-Vimentin proteins, have positive correlation in metastatic progression of melanoma into lung in both in-vitro and in-vivo condition, establishing it as therapeutic target. Pharmacologically, WFA targets this complex by extending its activity by not only inducing specific Serine 56 phosphorylation of Vimentin, also dissociates NEDD9 signaling loop to halt Epithelial-mesenchymal transition (EMT) and subsequent metastatic events. Eventually, modulation of the relevant metastatic genes E-Cadherin, N-Cadherin, SNAIL, MMP-2 & MMP-9 resulted in regression of metastatic melanoma progression to lung. The study validates WFA induced S56 phosphorylation is necessary to abrupt the NEDD9-Vimentin metastatic signaling complex to regress aggressive metastatic melanoma. The investigation emphasized more mechanistic approach of WFA. Understanding and targeting such integrative mechanical input in the tumor microenvironment will be a better therapeutic strategy to combat metastasis.

Post-Translational Modifications of Proteins Orchestrate All Hallmarks of Cancer

Post-translational modifications (PTMs) of proteins dynamically build the buffering and adapting interface between oncogenic mutations and environmental stressors, on the one hand, and cancer cell structure, functioning, and behavior. Aberrant PTMs can be considered as enabling characteristics of cancer as long as they orchestrate all malignant modifications and variability in the proteome of cancer cells, cancer-associated cells, and tumor microenvironment (TME). On the other hand, PTMs of proteins can enhance anticancer mechanisms in the tumoral ecosystem or sustain the beneficial effects of oncologic therapies through degradation or inactivation of carcinogenic proteins or/and activation of tumor-suppressor proteins. In this review, we summarized and analyzed a wide spectrum of PTMs of proteins involved in all regulatory mechanisms that drive tumorigenesis, genetic instability, epigenetic reprogramming, all events of the metastatic cascade, cytoskeleton and extracellular matrix (ECM) remodeling, angiogenesis, immune response, tumor-associated microbiome, and metabolism rewiring as the most important hallmarks of cancer. All cancer hallmarks develop due to PTMs of proteins, which modulate gene transcription, intracellular and extracellular signaling, protein size, activity, stability and localization, trafficking, secretion, intracellular protein degradation or half-life, and protein-protein interactions (PPIs). PTMs associated with cancer can be exploited to better understand the underlying molecular mechanisms of this heterogeneous and chameleonic disease, find new biomarkers of cancer progression and prognosis, personalize oncotherapies, and discover new targets for drug development.

The Cancer Chimera: Impact of Vimentin and Cytokeratin Co-Expression in Hybrid Epithelial/Mesenchymal Cancer Cells on Tumor Plasticity and Metastasis

The epithelial-mesenchymal transition (EMT) program is critical to metastatic cancer progression. EMT results in the expression of mesenchymal proteins and enhances migratory and invasive capabilities. In a small percentage of cells, EMT results in the expression of stemness-associated genes that provide a metastatic advantage. Although EMT had been viewed as a binary event, it has recently become clear that the program leads to a spectrum of phenotypes, including hybrid epithelial/mesenchymal (E/M) cells that have significantly greater metastatic capability than cells on the epithelial or mesenchymal ends of the spectrum. As hybrid E/M cells are rarely observed in physiological, non-diseased states in the adult human body, these cells are potential biomarkers and drug targets. Hybrid E/M cells are distinguished by the co-expression of epithelial and mesenchymal proteins, such as the intermediate filament proteins cytokeratin (CK; epithelial) and vimentin (VIM; mesenchymal). Although these intermediate filaments have been extensively used for pathological characterization and detection of aggressive carcinomas, little is known regarding the interactions between CK and VIM when co-expressed in hybrid E/M cells. This review describes the characteristics of hybrid E/M cells with a focus on the unique co-expression of VIM and CK. We will discuss the structures and functions of these two intermediate filament proteins and how they may interact when co-expressed in hybrid E/M cells. Additionally, we review what is known about cell-surface expression of these intermediate filament proteins and discuss their potential as predictive biomarkers and therapeutic targets.

CAR-T lymphocyte-based cell therapies; mechanistic substantiation, applications and biosafety enhancement with suicide genes: new opportunities to melt side effects

Immunotherapy has made significant strides in cancer treatment with strategies like checkpoint blockade antibodies and adoptive T cell transfer. Chimeric antigen receptor T cells (CAR-T) have emerged as a promising approach to combine these strategies and overcome their limitations. This review explores CAR-T cells as a living drug for cancer treatment. CAR-T cells are genetically engineered immune cells designed to target and eliminate tumor cells by recognizing specific antigens. The study involves a comprehensive literature review on CAR-T cell technology, covering structure optimization, generations, manufacturing processes, and gene therapy strategies. It examines CAR-T therapy in haematologic cancers and solid tumors, highlighting challenges and proposing a suicide gene-based mechanism to enhance safety. The results show significant advancements in CAR-T technology, particularly in structure optimization and generation. The manufacturing process has improved for broader clinical application. However, a series of inherent challenges and side effects still need to be addressed. In conclusion, CAR-T cells hold great promise for cancer treatment, but ongoing research is crucial to improve efficacy and safety for oncology patients. The proposed suicide gene-based mechanism offers a potential solution to mitigate side effects including cytokine release syndrome (the most common toxic side effect of CAR-T therapy) and the associated neurotoxicity.

[Plectin Promotes the Migration of Hepatocellular Carcinoma Cells Through Inducing F-actin Polymerization]

Objective

To explore the relationship between the expression of plectin and the migration of hepatocellular carcinoma (HCC) cells and to elucidate the molecular mechanisms by which plectin expression affects the migration of HCC cells.

Methods

First of all, Western blot was performed to determine the expression of plectin in normal hepatocytes and HCC cells. Secondly, a plectin-downregulated HCC cell strain was established and the control group (shNC group) and shPLEC group were set up. Each group was divided into a vehicle control group (shNC+DMSO group or shPLEC+DMSO group) and a F-actin cytoskeleton polymerization inducer Jasplakinolide group (shNC+Jasp group or shPLEC+Jasp group). Western blot was performed to determine the expression of plectin and epithelial-mesenchymal transition (EMT)-related proteins, including N-cadherin, vimentin, and E-cadherin. HCC cell migration was evaluated by Transwell assay. KEGG (Kyoto Encyclopedia of Genes and Genomes) was used to analyze the signaling pathways related to plectin gene. The polymerization of F-actin was analyzed by immunofluorescence assay.

Results

Compared with the normal hepatocytes, HCC cells showed high expression of plectin. Compared with those in the shNC group, the expression of plectin in the shPLEC group was decreased (P<0.05), the migration ability of HCC cells was weakened (P<0.05), and the EMT process was inhibited (with the expression of N-cadherin and vimentin being decreased and the expression of E-cadherin being increased) (P<0.05). KEGG analysis showed that the regulation of cytoskeletal F-actin was most closely associated with plectin and cytoskeletal F-actin depolymerized in the shPLEC group. After treatment with Jasplakinolide, an inducer of F-actin cytoskeleton polymerization, the migration ability of HCC cells in the shPLEC+Jasp group was enhanced compared with that of shPLEC+DMSO group (P<0.05) and the EMT process was restored (with the expression of N-cadherin and vimentin being increased and the expression of E-cadherin being decreased) (P<0.05). In addition, the polymerization of cytoskeletal F-actin in HCC cells was also restored.

Conclusion

Plectin is highly expressed in HCC cells. Plectin promotes the migration and the EMT of HCC cells through inducing F-actin polymerization.