The Evaluation of the N-cadherin Promoter's ability to Block EMT by Specific Expression of Diphtheria Toxin in EMT-induced A549 Cell Lines.

During epithelial to mesenchymal transition, the ability of cancer cells to transform and metastasize is primarily determined by N-cadherin-mediated migration and invasion. This study aimed to evaluate whether the N-cadherin promoter can induce diphtheria toxin expression as a suicide gene in epithelial to mesenchymal transition (EMT)-induced cancer cells and whether this can be used as potential gene therapy. To investigate the expression of diphtheria toxin under the N-cadherin promoter, the promoter was synthesized, and was cloned upstream of diphtheria toxin in a pGL3-Basic vector. The A-549 cells was transfected by electroporation. After induction of EMT by TGF-ß and hypoxia treatment, the relative expression of diphtheria toxin, mesenchymal genes such as N-cadherin and Vimentin, and epithelial genes such as E-cadherin and ß-catenin were measured by real-time PCR. MTT assay was also performed to measure cytotoxicity. Finally, cell motility was assessed by the Scratch test. After induction of EMT in transfected cells, the expression of mesenchymal markers such as Vimentin and N-cadherin significantly decreased, and the expression of ß-catenin increased. In addition, the MTT assay showed promising toxicity results after induction of EMT with TGF-ß in transfected cells, but toxicity was less effective in hypoxia. The scratch test results also showed that cell movement was successfully prevented in EMT-transfected cells and thus confirmed EMT occlusion. Our findings indicate that by using structures containing diphtheria toxin downstream of a specific EMT promoter such as the N-cadherin promoter, the introduced toxin can kill specifically and block EMT in cancer cells.

[Expression of DARS2 in colorectal cancer and its clinical significance].

Objective: To investigate the expression of DARS2 and its clinical significance in colorectal cancer. Methods: In this study, bioinformatics tools, especially gene expression profile interactive analysis 2 (GEPIA2), were used to conduct an in-depth analysis of DARS2 expression in colorectal cancer tissues. Immunohistochemical staining was carried out in 108 colorectal cancer specimens and 30 normal colorectal tissues obtained from the First Affiliated Hospital of Nanchang University, Nanchang, China. Colorectal cancer cell lines (HCT116 and SW480) were transfected with small interfering RNA (siRNA) and DARS2 overexpression plasmid to examine the effects of DARS2 knockdown and overexpression on cell function. To assess the effects on cell function, CCK8 and transwell migration assays were used to assess proliferation and cell motility, respectively. Additionally, protein immunoblotting was employed to scrutinize the expression of proteins associated with the epithelial-mesenchymal transition of colorectal cancer cells. Results: DARS2 exhibited a pronounced upregulation in expression within colorectal cancer tissues compared to their normal epithelial counterparts. Furthermore, DARS2 expression was higher in colorectal cancer of stage Ⅲ-Ⅳ than those of stage Ⅰ-Ⅱ, exhibiting a significant correlation with N staging, M staging, and pathological staging (P<0.05). Kaplan-Meier analyses showed a decreased overall survival rate in colorectal cancer with DARS2 expression compared to those without DARS2 expression (P<0.05). In the siRNA transfection group, there was a significant reduction in cell proliferation and migration (P<0.01 and P<0.05, respectively). Conversely, the transfection of DARS2 overexpression plasmids substantially increased both cell proliferation and migration (P<0.05). Additionally, immunoblotting revealed that DARS2 knockdown led to an upregulation of E-cadherin expression and a downregulation of N-cadherin and vimentin expression. In contrast, DARS2 overexpression resulted in increased N-cadherin and vimentin expression, coupled with reduction in E-cadherin expression. Conclusions: There is a strong association between DARS2 expression and colorectal cancer progression. Silencing DARS2 inhibits cell proliferation and migration, exerting a discernible influence on the epithelial-mesenchymal transition process.

Increasing the radiation-induced cytotoxicity by silver nanoparticles and docetaxel in prostate cancer cells.

BACKGROUND: Radiation therapy is utilized for treatment of localized prostate cancer. Nevertheless, cancerous cells frequently develop radiation resistance. While higher radiation doses have not always been effective, radiosensitizers have been extensively studied for their ability to enhance the cytotoxic effects of radiation. So, this study aims to evaluate the possible radiosensitization effects of docetaxel (DTX) and silver nanoparticles (SNP) in LNCaP cells. METHODS: The cytotoxic effects of DTX, SNP and 2 Gy of X-Ray radiation treatments were assessed in human LNCaP cell line using the MTT test after 24 h. Moreover, the effects of DTX, SNP and radiation on Epidermal growth factor (EGF), Caspase 3, inducible nitric oxide synthase and E-cadherin gene expression were analyzed using the Real-time PCR method. The level of Hydrogen peroxide (H2O2), an oxidative stress marker, was also detected 24 h after various single and combined treatments. RESULTS: The combinations of SNP (in low toxic concentration) and/or DTX (0.25× IC50 and 0.5 × IC50 concentrations for triple and double combinations respectively) with radiation induced significant cytotoxicity in LNCaP cells in comparison to monotherapies. These cytotoxic effects were associated with the downregulation of EGF mRNA. Additionally, H2O2 levels increased after Radiation + SNP + DTX triple combination and double combinations including Radiation + SNP and Radiation + DTX versus single treatments. The triple combination treatment also increased Caspase 3 and and E-cadherin mRNA levels in compared to single treatments in LNCaP cells. CONCLUSION: Our results indicate that the combination of SNP and DTX with radiation induces significant anti-cancer effects. Upregulation of Caspase 3 and E-cadherin gene expression, and decreased mRNA expression level of EGF may be exerted specifically by use of this combination versus single treatments.

Exchangeable leaders of collectively migrating glioma abuse N-cadherin trafficking.

Collectively migrating cells consist of leaders and followers with different features. In this issue, Kim et al. (https://doi.org/10.1083/jcb.202401057) characterize the leader and follower cells in collective glioma migration and uncover important roles of YAP1/TAZ-mediated regulation of N-cadherin in the leader cells.

N6-methyladenosine modification of KLF2 may contribute to endothelial-to-mesenchymal transition in pulmonary hypertension.

BACKGROUND: Pulmonary hypertension (PH) is a progressive disease characterized by pulmonary vascular remodeling. Increasing evidence indicates that endothelial-to-mesenchymal transition (EndMT) in pulmonary artery endothelial cells (PAECs) is a pivotal trigger initiating this remodeling. However, the regulatory mechanisms underlying EndMT in PH are still not fully understood. METHODS: Cytokine-induced hPAECs were assessed using RNA methylation quantification, qRT-PCR, and western blotting to determine the involvement of N6-methyladenosine (m6A) methylation in EndMT. Lentivirus-mediated silencing, overexpression, tube formation, and wound healing assays were utilized to investigate the function of METTL3 in EndMT. Endothelial-specific gene knockout, hemodynamic measurement, and immunostaining were performed to explore the roles of METTL3 in pulmonary vascular remodeling and PH. RNA-seq, RNA Immunoprecipitation-based qPCR, mRNA stability assay, m6A mutation, and dual-luciferase assays were employed to elucidate the mechanisms of RNA methylation in EndMT. RESULTS: The global levels of m6A and METTL3 expression were found to decrease in TNF-α- and TGF-ß1-induced EndMT in human PAECs (hPAECs). METTL3 inhibition led to reduced endothelial markers (CD31 and VE-cadherin) and increased mesenchymal markers (SM22 and N-cadherin) as well as EndMT-related transcription factors (Snail, Zeb1, Zeb2, and Slug). The endothelial-specific knockout of Mettl3 promoted EndMT and exacerbated pulmonary vascular remodeling and hypoxia-induced PH (HPH) in mice. Mechanistically, METTL3-mediated m6A modification of kruppel-like factor 2 (KLF2) plays a crucial role in the EndMT process. KLF2 overexpression increased CD31 and VE-cadherin levels while decreasing SM22, N-cadherin, and EndMT-related transcription factors, thereby mitigating EndMT in PH. Mutations in the m6A site of KLF2 mRNA compromise KLF2 expression, subsequently diminishing its protective effect against EndMT. Furthermore, KLF2 modulates SM22 expression through direct binding to its promoter. CONCLUSIONS: Our findings unveil a novel METTL3/KLF2 pathway critical for protecting hPAECs against EndMT, highlighting a promising avenue for therapeutic investigation in PH.

Inhibitory effect of recombinant tyrosine­sulfated madanin­1, a thrombin inhibitor, on the behavior of MDA­MB­231 and SKOV3 cells in vitro.

Thrombin, which plays a crucial role in hemostasis, is also implicated in cancer progression. In the present study, the effects of the thrombin­targeting recombinant tyrosine­sulfated madanin­1 on cancer cell behavior and signaling pathways compared with madanin­1 wild­type (WT) were investigated. Recombinant madanin­1 2 sulfation (madanin­1 2S) and madanin­1 WT proteins were generated using Escherichia coli. SKOV3 and MDA­MB­231 cells were treated with purified recombinant proteins with or without thrombin stimulation. Migration and invasion of cells were analyzed by wound healing assay and Transwell assay, respectively. Thrombin markedly increased cell migration and invasion in both SKOV3 and MDA­MB­231 cells, which were significantly suppressed by madanin­1 2S (P<0.05). Madanin­1 2S also significantly suppressed thrombin­induced expression of phosphorylated (p)­Akt and p­extracellular signal­regulated kinase in both cell lines (P<0.05), whereas madanin­1 WT had no effect on the expression levels of these proteins in MDA­MB­231 cells. Furthermore, madanin­1 2S significantly reversed the effects of thrombin on E­cadherin, N­cadherin and vimentin expression in MDA­MB­231 cells (P<0.05), whereas madanin­1 WT did not show any effect. In conclusion, madanin­1 2S suppressed the migration and invasion of cancer cells more effectively than madanin­1 WT. It is hypothesized that inhibiting thrombin via the sulfated form of madanin­1 may be a potential candidate for enhanced cancer therapy; however, further in vivo validation is required.

[Trends, challenges, and reflections on early-onset gastric cancer].

Early onset gastric cancer (EOGC), as a distinct type of gastric cancer, has seen a gradually increasing incidence in recent years, imposing significant negative impacts on society and families, and has attracted widespread attention. EOGC presents a series of clinical characteristics, such as a higher prevalence among women, pathological types predominantly being poorly differentiated or undifferentiated, and Lauren classification often being diffuse, making it more prone to distant metastasis. However, the causes and mechanisms of its onset are not yet fully understood. Notably, about 10% of EOGC cases exhibit familial clustering and germline mutations in the Cadherin-1 (CDH1) or α-1 catenin (CTNNA1) genes, known as hereditary diffuse gastric cancer (HDGC). These unique clinical features pose significant challenges for the diagnosis and treatment of EOGC. The core of treatment for early onset gastric cancer focuses on strong efficacy, function preservation, rehabilitation, and social reintegration. Clinically, a multidisciplinary approach and comprehensive treatment are essential, with equal emphasis on physiological and psychological aspects, balancing therapeutic effectiveness with functional outcomes, to benefit more patients with EOGC.

Analysis of CDO1, PITX2, and CDH13 Gene Methylation in Early Endometrial Cancer for Prediction of Medical Treatment Outcomes.

An observational cohort study of patients diagnosed with endometrial cancer (EC) stage IA G1, or atypical endometrial hyperplasia (AEH), undergoing organ-preserving treatment, was conducted. OBJECTIVE OF THE STUDY: To determine CDO1, PITX2, and CDH13 gene methylation levels in early endometrial cancer and atypical hyperplasia specimens obtained before organ-preserving treatment in the patients with adequate response and with insufficient response to hormonal treatment. MATERIALS AND METHODS: A total of 41 endometrial specimens obtained during diagnostic uterine curettage in women with EC (n = 28) and AEH (n = 13), willing to preserve reproductive function, were studied; 18 specimens of uterine cancer IA stage G1 from peri- and early postmenopausal women (comparison group) were included in the study. The control group included 18 endometrial specimens from healthy women obtained by diagnostic curettage for missed abortion and/or intrauterine adhesions. Methylation levels were analyzed using the modified MS-HRM method. RESULTS: All 13 women with AEH had a complete response (CR) to medical treatment. In the group undergoing organ-preserving treatment for uterine cancer IA stage G1 (n = 28), 14 patients had a complete response (EC CR group) and 14 did not (EC non-CR group). It was found that all groups had statistically significant differences in CDO1 gene methylation levels compared to the control group (p < 0.001) except for the EC CR group (p = 0.21). The p-value for the difference between EC CR and EC non-CR groups was <0.001. The differences in PITX2 gene methylation levels between the control and study groups were also significantly different (p < 0.001), except for the AEH group (p = 0.21). For the difference between EC CR and EC non-CR groups, the p-value was 0.43. For CDH13 gene methylation levels, statistically significant differences were found between the control and EC non-CR groups (p < 0.001), and the control and EC comparison groups (p = 0.005). When comparing the EC CR group with EC non-CR group, the p-value for this gene was <0.001. The simultaneous assessment of CDO1 and CDH13 genes methylation allowed for an accurate distinction between EC CR and EC non-CR groups (AUC = 0.96). CONCLUSION: The assessment of CDO1 and CDH13 gene methylation in endometrial specimens from patients with endometrial cancer (IA stage G1), scheduled for medical treatment, can predict the treatment outcome.

Comparison of vestibular function in hereditary hearing loss patients with GJB2, CDH23, and SLC26A4 variants.

To investigate the association between hereditary hearing loss and vestibular function, we compared vestibular function and symptoms among patients with GJB2, SLC26A4, and CDH23 variants. Thirty-nine patients with sensory neural hearing loss (11 males and 28 females) with biallelic pathogenic variants in either GJB2, SLC26A4, or CDH23 were included in this study (13 GJB2, 15 SLC26A4, and 11 CDH23). The patients were examined using caloric testing and cervical and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP). We also compared vestibular function and symptoms between patients with these gene variants and 78 normal-hearing ears without vestibular symptoms as controls. The frequency of semicircular canal hypofunction in caloric testing was higher in patients with SLC26A4 variants (47%) than in those with GJB2 (0%) and CDH23 variants (27%). According to the cVEMP results, 69% of patients with GJB2 variants had saccular hypofunction, a significantly higher proportion than in those carrying other variants (SLC26A4, 20%; CDH23, 18%). In oVEMP, which reflects utricular function, no difference was observed in the frequency of hypofunction among the three genes (GJB2, 15%; SLC26A4, 40%; and CDH23, 36%). Hence, discernable trends indicate vestibular dysfunction associated with each gene.

Hsa_circ_0051908 Promotes Hepatocellular Carcinoma Progression by Regulating the Epithelial-Mesenchymal Transition Process.

Materials and Methods: Hsa_circ_0051908 expression was determined using RT-qPCR. HCC cell proliferation, apoptosis, invasion, and migration were assessed using CCK-8 assay, EdU staining, TUNEL staining, flow cytometry, and transwell assay. The molecular mechanism was analyzed using western blotting. In addition, the role of hsa_circ_0051908 in tumor growth was evaluated in vivo. Results: Hsa_circ_0051908 expression was increased in both HCC tissues and cell lines. The proliferation, migration, and invasion of HCC cells were significantly decreased after hsa_circ_0051908 knockdown, while cell apoptosis was notably increased. Furthermore, we found that hsa_circ_0051908 silencing downregulated vimentin and Snail and upregulated E-cadherin. In vivo, hsa_circ_0051908 silencing significantly inhibited the growth of the tumor. Conclusions: Our data provide evidence that hsa_circ_0051908 promotes HCC progression partially by mediating the epithelial-mesenchymal transition process, and it may be used for HCC treatment.

FAT1 inhibits the proliferation of DLBCL cells via increasing the m6A modification of YAP1 mRNA.

Emerging evidence shows that FAT atypical cadherin 1 (FAT1) mutations occur in lymphoma and are associated with poorer overall survival. Considering that diffuse large B cell lymphoma (DLBCL) is the category of lymphoma with the highest incidence rate, this study aims to explore the role of FAT1 in DLBCL. The findings demonstrate that FAT1 inhibits the proliferation of DLBCL cell lines by downregulating the expression of YAP1 rather than by altering its cellular localization. Mechanistic analysis via meRIP-qPCR/luciferase reporter assays showed that FAT1 increases the m6A modification of YAP1 mRNA 3'UTR and the subsequent binding of heterogeneous nuclear ribonucleoprotein D (HNRNPD) to the m6A modified YAP1 mRNA, thus decreasing the stability of YAP1 mRNA. Furthermore, FAT1 increases YAP1 mRNA 3'UTR m6A modification by decreasing the activity of the TGFß-Smad2/3 pathway and the subsequent expression of ALKBH5, which is regulated at the transcriptional level by Smad2/3. Collectively, these results reveal that FAT1 inhibits the proliferation of DLBCL cells by increasing the m6A modification of the YAP1 mRNA 3'UTR via the TGFß-Smad2/3-ALKBH5 pathway. The findings of this study therefore indicate that FAT1 exerts anti-tumor effects in DLBCL and may represent a novel target in the treatment of this form of lymphoma.

SMAD4 promotes somatic-germline contact during murine oocyte growth.

Development of the mammalian oocyte requires physical contact with the surrounding granulosa cells of the follicle, which provide it with essential nutrients and regulatory signals. This contact is achieved through specialized filopodia, termed transzonal projections (TZPs), that extend from the granulosa cells to the oocyte surface. Transforming growth factor (TGFß) family ligands produced by the oocyte increase the number of TZPs, but how they do so is unknown. Using an inducible Cre recombinase strategy together with expression of green fluorescent protein to verify Cre activity in individual cells, we examined the effect of depleting the canonical TGFß mediator, SMAD4, in mouse granulosa cells. We observed a 20-50% decrease in the total number of TZPs in SMAD4-depleted granulosa cell-oocyte complexes, and a 50% decrease in the number of newly generated TZPs when the granulosa cells were reaggregated with wild-type oocytes. Three-dimensional image analysis revealed that TZPs of SMAD4-depleted cells were longer than controls and more frequently oriented towards the oocyte. Strikingly, the transmembrane proteins, N-cadherin and Notch2, were reduced by 50% in SMAD4-depleted cells. SMAD4 may thus modulate a network of cell adhesion proteins that stabilize the attachment of TZPs to the oocyte, thereby amplifying signalling between the two cell types.

PCDH17 restricts dendritic spine morphogenesis by regulating ROCK2-dependent control of the actin cytoskeleton, modulating emotional behavior.

Proper regulation of synapse formation and elimination is critical for establishing mature neuronal circuits and maintaining brain function. Synaptic abnormalities, such as defects in the density and morphology of postsynaptic dendritic spines, underlie the pathology of various neuropsychiatric disorders. Protocadherin 17 (PCDH17) is associated with major mood disorders, including bipolar disorder and depression. However, the molecular mechanisms by which PCDH17 regulates spine number, morphology, and behavior remain elusive. In this study, we found that PCDH17 functions at postsynaptic sites, restricting the number and size of dendritic spines in excitatory neurons. Selective overexpression of PCDH17 in the ventral hippocampal CA1 results in spine loss and anxiety- and depression-like behaviors in mice. Mechanistically, PCDH17 interacts with actin-relevant proteins and regulates actin filament (F-actin) organization. Specifically, PCDH17 binds to ROCK2, increasing its expression and subsequently enhancing the activity of downstream targets such as LIMK1 and the phosphorylation of cofilin serine-3 (Ser3). Inhibition of ROCK2 activity with belumosudil (KD025) ameliorates the defective F-actin organization and spine structure induced by PCDH17 overexpression, suggesting that ROCK2 mediates the effects of PCDH17 on F-actin content and spine development. Hence, these findings reveal a novel mechanism by which PCDH17 regulates synapse development and behavior, providing pathological insights into the neurobiological basis of mood disorders.

Mice with deficiency in Pcdh15, a gene associated with bipolar disorders, exhibit significantly elevated diurnal amplitudes of locomotion and body temperature.

Genetic factors significantly affect the pathogenesis of psychiatric disorders. However, the specific pathogenic mechanisms underlying these effects are not fully understood. Recent extensive genomic studies have implicated the protocadherin-related 15 (PCDH15) gene in the onset of psychiatric disorders, such as bipolar disorder (BD). To further investigate the pathogenesis of these psychiatric disorders, we developed a mouse model lacking Pcdh15. Notably, although PCDH15 is primarily identified as the causative gene of Usher syndrome, which presents with visual and auditory impairments, our mice with Pcdh15 homozygous deletion (Pcdh15-null) did not exhibit observable structural abnormalities in either the retina or the inner ear. The Pcdh15-null mice showed very high levels of spontaneous motor activity which was too disturbed to perform standard behavioral testing. However, the Pcdh15 heterozygous deletion mice (Pcdh15-het) exhibited enhanced spontaneous locomotor activity, reduced prepulse inhibition, and diminished cliff avoidance behavior. These observations agreed with the symptoms observed in patients with various psychiatric disorders and several mouse models of psychiatric diseases. Specifically, the hyperactivity may mirror the manic episodes in BD. To obtain a more physiological, long-term quantification of the hyperactive phenotype, we implanted nano tag® sensor chips in the animals, to enable the continuous monitoring of both activity and body temperature. During the light-off period, Pcdh15-null exhibited elevated activity and body temperature compared with wild-type (WT) mice. However, we observed a decreased body temperature during the light-on period. Comprehensive brain activity was visualized using c-Fos mapping, which was assessed during the activity and temperature peak and trough. There was a stark contrast between the distribution of c-Fos expression in Pcdh15-null and WT brains during both the light-on and light-off periods. These results provide valuable insights into the neural basis of the behavioral and thermal characteristics of Pcdh15-deletion mice. Therefore, Pcdh15-deletion mice can be a novel model for BD with mania and other psychiatric disorders, with a strong genetic component that satisfies both construct and surface validity.

Mosaicism-independent mechanisms contribute to Pcdh19-related epilepsy and repetitive behaviors in Xenopus.

Protocadherin19 (PCDH19)-related epilepsy syndrome is a rare disorder characterized by early-onset epilepsy, intellectual disability, and autistic behaviors. PCDH19 is located on the X chromosome and encodes a calcium-dependent single-pass transmembrane protein, which regulates cell-to-cell adhesion through homophilic binding. In human, 90% of heterozygous females, containing PCDH19 wild-type and mutant cells due to random X inactivation, are affected, whereas mutant males, containing only mutant cells, are typically not. The current view, the cellular interference, is that the altered interactions between wild-type and mutant cells during development, rather than loss of function itself, are responsible. However, studies using Pcdh19 knockout mice showed that the complete loss of function also causes autism-like behaviors both in males and females, suggesting that other functions of PCDH19 may also contribute to pathogenesis. To address whether mosaicism is required for PCDH19-related epilepsy, we generated Xenopus tropicalis tadpoles with complete or mosaic loss of function by injecting antisense morpholino oligonucleotides into the blastomeres of neural lineage at different stages of development. We found that either mosaic or complete knockdown results in seizure-like behaviors, which could be rescued by antiseizure medication, and repetitive behaviors. Our results suggest that the loss of PCDH19 function itself, in addition to cellular interference, may also contribute to PCDH19-related epilepsy.

KLRG1-expressing CD8+ T cells are exhausted and polyfunctional in patients with chronic hepatitis B.

Killer cell lectin-like receptor G1 (KLRG1) has traditionally been regarded as an inhibitory receptor of T cell exhaustion in chronic infection and inflammation. However, its exact role in hepatitis B virus (HBV) infection remains elusive. CD8+ T cells from 190 patients with chronic hepatitis B were analyzed ex vivo for checkpoint and apoptosis markers, transcription factors, cytokines and subtypes in 190 patients with chronic hepatitis B. KLRG1+ and KLRG1- CD8+ T cells were sorted for transcriptome analysis. The impact of the KLRG1-E-cadherin pathway on the suppression of HBV replication mediated by virus-specific T cells was validated in vitro. As expected, HBV-specific CD8+ T cells expressed higher levels of KLRG1 and showed an exhausted molecular phenotype and function. However, despite being enriched for the inhibitory molecules, thymocyte selection-associated high mobility group box protein (TOX), eomesodermin (EOMES), and Helios, CD8+ T cells expressing KLRG1 produced significant levels of tumour necrosis factor (TNF)-α, interferon (IFN)-γ, perforin, and granzyme B, demonstrating not exhausted but active function. Consistent with the in vitro phenotypic assay results, RNA sequencing (RNA-seq) data showed that signature effector T cell and exhausted T cell genes were enriched in KLRG1+ CD8+ T cells. Furthermore, in vitro testing confirmed that KLRG1-E-cadherin binding inhibits the antiviral efficacy of HBV-specific CD8+ T cells. Based on these findings, we concluded that KLRG1+ CD8+ T cells are not only a terminally exhausted subgroup but also exhibit functional diversity, despite inhibitory signs in HBV infection.

Inhibition of δ-catenin palmitoylation slows the progression of prostate cancer.

Prostate cancer (PCa) is the second leading cause of death in males. It has been reported that δ-catenin expression is upregulated during the late stage of prostate cancer. Palmitoylation promotes protein transport to the cytomembrane and regulates protein localization and function. However, the effect of δ-catenin palmitoylation on the regulation of cancer remains unknown. In this study, we utilized prostate cancer cells overexpressing mutant δ-catenin (J6A cells) to induce a depalmitoylation phenotype and investigate its effect on prostate cancer. Our results indicated that depalmitoylation of δ-catenin not only reduced its membrane expression but also promoted its degradation in the cytoplasm, resulting in a decrease in the effect of EGFR and E-cadherin signaling. Consequently, depalmitoylation of δ-catenin reduced the proliferation and metastasis of prostate cancer cells. Our findings provide novel insights into potential therapeutic strategies for controlling the progression of prostate cancer through palmitoylation-based targeting of δ-catenin.

Leptin Promotes Vasculogenic Mimicry in Breast Cancer Cells by Regulating Aquaporin-1.

Leptin is an obesity-related hormone that plays an important role in breast cancer progression. Vasculogenic mimicry (VM) refers to the formation of vascular channels lined by tumor cells. This study aimed to investigate the relationship between leptin and VM in human breast cancer cells. VM was measured by a 3D culture assay. Signal transducers and activators of transcription 3 (STAT3) signaling, aquaporin-1 (AQP1), and the expression of VM-related proteins, including vascular endothelial cadherin (VE-cadherin), twist, matrix metalloproteinase-2 (MMP-2), and laminin subunit 5 gamma-2 (LAMC2), were examined by Western blot. AQP1 mRNA was analyzed by a reverse transcriptase-polymerase chain reaction (RT-PCR). Leptin increased VM and upregulated phospho-STAT3, VE-cadherin, twist, MMP-2, and LAMC2. These effects were inhibited by the leptin receptor-blocking peptide, Ob-R BP, and the STAT3 inhibitor, AG490. A positive correlation between leptin and AQP1 mRNA was observed and was confirmed by RT-PCR. Leptin upregulated AQP1 expression, which was blocked by Ob-R BP and AG490. AQP1 overexpression increased VM and the expression of VM-related proteins. AQP1 silencing inhibited leptin-induced VM and the expression of VM-related proteins. Thus, these results showed that leptin facilitates VM in breast cancer cells via the Ob-R/STAT3 pathway and that AQP1 is a key mediator in leptin-induced VM.

Targeting tumorous Circ-E-Cadherinencoded C-E-Cad inhibits the recruitment and function of breast cancer-associated myeloid-derived suppressor cells.

We previously demonstrated that the C-E-cad protein encoded by circ-E-cadherin promotes the self-renewal of glioma stem cells. The expression pattern of C-E-cad in breast cancer and its potential function in the tumor microenvironment are unclear. The expression of circ-E-cadherin and C-E-cad was detected in breast cancer specimens. The influence of C-E-cad expression on MDSCs was assessed using FACS and in vivo tumorigenesis experiments. The synergistic effect of anti-C-E-cad and anti-PD-1 antibodies was validated in vivo. circ-E-cadherin and the encoded protein C-E-cad were found to be upregulated in breast cancer vs. normal samples. C-E-cad promotes the recruitment of MDSCs, especially PMN-MDSCs. C-E-cad activates EGFR signaling in tumor cells and promotes the transcription of CXCL8; moreover, C-E-cad binds to MDSCs and maintains glycolysis in PMN-MDSCs. Targeting C-E-cad enhanced anti-PD-1 efficiency. Our data suggested that C-E-cad is markedly overexpressed in breast cancer and promotes MDSC recruitment and survival. Targeting C-E-cad increases the efficacy of immune checkpoint inhibitor therapy.

Pseudogene CSPG4P12 inhibits colorectal cancer progression by attenuating epithelial-mesenchymal transition.

Colorectal cancer is one of the most common malignant cancers. Pseudogenes have been identified as oncogenes or tumor suppressor genes in the development of various cancers. However, the function of pseudogene CSPG4P12 in colorectal cancer remains unclear. Therefore, the aim of this study was to investigate the potential role of CSPG4P12 in colorectal cancer and explore the possible underlying mechanism. The difference of CSPG4P12 expression between colorectal cancer tissues and adjacent normal tissues was analyzed using the online Gene Expression Profiling Interactive Analysis 2 (GEPIA2) database. Cell viability and colony formation assays were conducted to evaluate cell viability. Transwell and wound healing assays were performed to assess cell migration and invasion capacities. Western blot was used to measure the expression levels of epithelial-mesenchymal transition-related proteins. Colorectal cancer tissues had lower CSPG4P12 expression than adjacent normal tissues. The overexpression of CSPG4P12 inhibited cell proliferation, invasion, and migration in colorectal cancer cells. Overexpressed CSPG4P12 promoted the expression of E-cadherin, whereas it inhibited the expression of vimentin, N-cadherin, and MMP9. These findings suggested that CSPG4P12 inhibits colorectal cancer development and may serve as a new potential target for colorectal cancer.