CALD1 promotes the expression of PD-L1 in bladder cancer via the JAK/STAT signaling pathway

Advances in research on flavonoids in tumor immunotherapy (Review)

Cancer immunotherapy is an approach used in anti‑tumor treatment; however, its efficacy is limited to specific tumor types that are inherently sensitive to immune system modulation. Expanding the scope of indications and enhancing the efficacy of cancer immunotherapy are key goals for continued advancement. Flavonoids modulate the tumor‑immunosuppressive microenvironment. Integrating flavonoids with immunotherapeutic modalities, including cancer vaccines, immune checkpoint inhibitors and adoptive immune‑cell therapy, has potential in terms of augmenting the therapeutic efficacy of immunotherapy. The present review aimed to summarize flavonoids that enhance cancer immunotherapy, focusing on their underlying mechanisms and the application of nanotechnology to overcome inherent limitations such as poor solubility, low bioavailability, rapid metabolism, and instability under physiological conditions, thereby highlighting the potential of flavonoids in advancing cancer immunotherapy.

The aryl hydrocarbon receptor controls IFN-γ-induced immune checkpoints PD-L1 and IDO via the JAK/STAT pathway in lung adenocarcinoma

While immunotherapy has shown some efficacy in lung adenocarcinoma (LUAD) patients, many respond only partially or not at all. One limitation in improving outcomes is the lack of a complete understanding of immune checkpoint regulation. Here, we investigated a possible link between an environmental chemical receptor implicated in lung cancer and immune regulation, the AhR, a known but counterintuitive mediator of immunosuppression (interferon (IFN)-γ), and regulation of two immune checkpoints (PD-L1 and IDO). AhR gene-edited LUAD cell lines, a syngeneic LUAD mouse model, bulk and scRNA sequencing of LUADs and tumor-infiltrating T cells were used to map out a signaling pathway leading from IFN-γ through the AhR to JAK/STAT, PD-L1, IDO, and tumor-mediated immunosuppression. The data demonstrate that: (1) IFN-γ activation of the JAK/STAT pathway leading to PD-L1 and IDO1 up-regulation is mediated by the AhR in murine and human LUAD cells, (2) AhR-driven IDO1 induction results in the production of Kynurenine (Kyn), an AhR ligand, which likely mediates an AhR→IDO1→Kyn→AhR amplification loop, (3) transplantation of AhR-knockout LUAD cells results in long-term tumor immunity in most recipients. (4) The 23% of AhR-knockout tumors that do grow do so at a much slower pace than controls and exhibit higher densities of CD8+ T cells expressing markers of immunocompetence, increased activity, and increased cell-cell communication. The data definitively link the AhR to IFN-γ-induced JAK/STAT pathway and immune checkpoint-mediated immunosuppression and support the targeting of the AhR in the context of LUAD.

CALD1 inhibits invasion of human ovarian cancer cells by affecting cytoskeletal structure and the number of focal adhesion

Background

Ovarian cancer (OV) is associated with the highest mortality rate among gynecological cancers, largely due to late diagnosis and chemoresistance. The identification of novel diagnostic markers and therapeutic targets is crucial. Caldesmon 1 (CALD1), a cytoskeleton-regulating protein, has been implicated in various cancers. This study aims to investigate the expression and functional significance of CALD1 in OV, focusing on its potential impact on cell invasion and metastasis.

Methods

We analyzed CALD1 expression using The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases, along with tissue microarray immunohistochemistry (IHC). Drug sensitivity analysis was performed using the 'oncopredict' R package. A CALD1 gene network was constructed, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. SK-OV-3 cell lines with stable CALD1 knockdown were established and verified by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB). We then assessed cell invasiveness using Transwell assays and visualized cytoskeletal changes through immunofluorescence staining of F-actin and Vinculin.

Results

The expression of CALD1 was significantly reduced in OV tissues compared to normal tissues. Patients with high and low expression levels of CALD1 showed significant differences in their response to chemotherapeutic drugs. CALD1 and its related genes were found to play an essential role in regulating cytoskeleton organization, focal adhesion formation, and cell movement processes. CALD1 knockdown cells exhibited a significant reduction in F-actin stress fibers, a loose cytoskeleton structure, decreased Vinculin expression, and enhanced migration ability.

Conclusions

Attenuated expression of CALD1 in SK-OV-3 cells leads to fewer F-actin stress fibers, reducing the association between the cytoskeleton and Vinculin. This results in reduced cellular focal adhesions and increased invasiveness of SK-OV-3 cells, promoting OV cell metastasis. These findings suggest that CALD1 may have important clinical implications in the diagnosis and treatment of OV.

Interferon-γ/Janus kinase 1/STAT1 Signaling Represses Forkhead Box A1 and Drives a Basal Transcriptional State in Muscle-Invasive Bladder Cancer

During progression, luminal muscle-invasive bladder cancer (MIBC) can transition to the aggressive basal-squamous (Ba/Sq) subtype. Reduced expression of forkhead box A1 (FOXA1) in the urothelium is a hallmark and driver of the Ba/Sq transcriptional state and squamous differentiation. Ba/Sq tumors are highly inflamed; however, the specific inflammatory pathways contributing to the Ba/Sq state are unknown. In this study, transcriptomic analyses of The Cancer Genome Atlas MIBC cohort were performed to determine whether immune response gene signatures were associated with MIBC molecular states. Results showed that Ba/Sq MIBCs were enriched for the interferon-γ (IFN-γ)-dominant signature. Ba/Sq MIBCs exhibited increased IFN-γ/Janus kinase (JAK)/STAT pathway activity, corresponding to reduced FOXA1 regulon activity. Immunohistochemistry of MIBC specimens demonstrated that JAK1 expression was significantly increased in tumor areas with squamous differentiation. IFN-γ treatment of luminal MIBC cell lines significantly decreased the expression of luminal transcriptional drivers, including FOXA1, and increased the expression of Ba/Sq markers in a STAT1-dependent manner. RNA-sequencing analyses identified IFN-γ as a driver of the Ba/Sq state. The ability of IFN-γ to repress FOXA1 in luminal cells was abrogated by ruxolitinib inhibition of JAK1/2 activity. Additionally, pharmacologic inhibition or genetic ablation of JAK1 restored FOXA1 expression in Ba/Sq MIBC cells. These findings are the first to identify IFN-γ as an epithelial cell-extrinsic mechanism to repress FOXA1 and drive the Ba/Sq state in MIBC.

MiRNA-21 promotes the migration and proliferation of prostate cancer cells via activating the JAK/STAT pathway

This research explored the role of microRNA (miRNA)-21 in prostate cancer (PCa) cells, as well as its regulation of the JAK/STAT pathway in PCa cells. Quantitative real-time PCR was employed to examine miRNA-21 expression in PCa cells. Cell viability and proliferation were detected by MTT and colony formation assays. Cell migration was measured by wound healing and transwell assays. The janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway-related protein expression was detected using western blot. The results indicated that miRNA-21 was significantly up-regulated in PCa cells, and inhibition of miRNA-21 suppressed the viability, proliferation and migration of PCa cells. Besides, inhibition of miRNA-21 lessened the levels of JAK/STAT pathway-related proteins in both PCa cells. Additionally, Ruxolitinib treatment (an inhibitor of the JAK/STAT pathway) could reverse the elevated cell viability and proliferation in miRNA-21 mimics-transfected PCa cells. Taken together, our study demonstrates that miRNA-21 promotes the migration and proliferation of PCa cells via activating the JAK /STAT pathway.

Partial Inhibition of Epithelial-to-Mesenchymal Transition (EMT) Phenotypes by Placenta-Derived DBMSCs in Human Breast Cancer Cell Lines, In Vitro

Stem cell-based therapies hold significant potential for cancer treatment due to their unique properties, including migration toward tumor niche, secretion of bioactive molecules, and immunosuppression. Mesenchymal stem cells (MSCs) from adult tissues can inhibit tumor progression, angiogenesis, and apoptosis of cancer cells. We have previously reported the isolation and characterization of placenta-derived decidua basalis mesenchymal stem cells (DBMSCs), which demonstrated higher levels of pro-migratory and anti-apoptotic genes, indicating potential anti-cancer effects. In this study, we analyzed the anti-cancer effects of DBMSCs on human breast cancer cell lines MDA231 and MCF7, with MCF 10A used as control. We also investigated how these cancer cells lines affect the functional competence of DBMSCs. By co-culturing DBMSCs with cancer cells, we analyzed changes in functions of both cell types, as well as alterations in their genomic and proteomic profile. Our results showed that treatment with DBMSCs significantly reduced the functionality of MDA231 and MCF7 cells, while MCF 10A cells remained unaffected. DBMSC treatment decreased epithelial-to-mesenchymal transition (EMT)-related protein levels in MDA231 cells and modulated expression of other cancer-related genes in MDA231 and MCF7 cells. Although cancer cells reduced DBMSC proliferation, they increased their expression of anti-apoptotic genes. These findings suggest that DBMSCs can inhibit EMT-related proteins and reduce the invasive characteristics of MDA231 and MCF7 breast cancer cells, highlighting their potential as candidates for cell-based cancer therapies.

The Aryl Hydrocarbon Receptor Controls IFNγ-Induced Immune Checkpoints PD-L1 and IDO via the JAK/STAT Pathway in Lung Adenocarcinoma

While immunotherapy has shown efficacy in lung adenocarcinoma (LUAD) patients, many respond only partially or not at all. One limitation in improving outcomes is the lack of a complete understanding of immune checkpoint regulation. Here, we investigated a possible link between an environmental chemical receptor implicated in lung cancer and immune regulation, (the aryl hydrocarbon receptor/AhR), a known but counterintuitive mediator of immunosuppression (IFNγ), and regulation of two immune checkpoints (PD-L1 and IDO). AhR gene-edited LUAD cell lines, a syngeneic LUAD mouse model, bulk- and scRNA sequencing of LUADs and tumor-infiltrating leukocytes were used to map out a signaling pathway leading from IFNγ through the AhR to JAK/STAT, PD-L1, IDO, and tumor-mediated immunosuppression. The data demonstrate that: 1) IFNγ activation of the JAK/STAT pathway leading to PD-L1 and IDO1 upregulation is mediated by the AhR in murine and human LUAD cells, 2) AhR-driven IDO1 induction results in the production of Kynurenine (Kyn), an AhR ligand, which likely mediates an AhR→IDO1→Kyn→AhR amplification loop, 3) transplantation of AhR-knockout LUAD cells results in long-term tumor immunity in most recipients. 4) The 23% of AhR-knockout tumors that do grow do so at a much slower pace than controls and exhibit higher densities of CD8+ T cells expressing markers of immunocompetence, increased activity, and increased cell-cell communication. The data definitively link the AhR to IFNγ-induced JAK/STAT pathway and immune checkpoint-mediated immunosuppression and support the targeting of the AhR in the context of LUAD.

XTP8 Promotes Ovarian Cancer Progression by Activating AKT/AMPK/mTOR Pathway to Regulate EMT

Ovarian cancer (OC) ranks as the fifth leading cause of cancer-related death in women. The main contributors to the poor prognosis of ovarian cancer are the high rates of recurrence and metastasis. Studies have indicated a crucial role for hepatitis B virus X Ag-Transactivated Protein 8 (XTP8), a protein containing the DEP domain, in various cellular processes, including cell growth, movement, and differentiation, across several types of cancers. However, the role of XTP8 in ovarian cancer remains unclear. We observed elevated expression of XTP8 in ovarian cancer. Silencing XTP8 inhibited cell proliferation, promoted apoptosis, and yielded contrasting results in cells overexpressing XTP8. Furthermore, XTP8 facilitated ovarian cancer invasion and migration, triggering epithelial-mesenchymal transition (EMT). Mechanistically, XTP8 silencing led to reduced phosphorylation levels of AKT, increased p-AMPK levels, and decreased p-mTOR levels, while XTP8 overexpression exerted the opposite effects. Additionally, the activation of p-AMPK rescued the promoting effect of XTP8 on EMT in ovarian cancer cell lines, indicating that XTP8 acts as an oncogene by modulating the AKT/AMPK/mTOR pathway. Through transcriptome sequencing to identify downstream targets of XTP8, we found that XTP8 influences the expression of Caldesmon (CALD1) at both transcriptional and translational levels. CALD1 can be considered a downstream target of XTP8. The collaborative action of XTP8 and CALD1 activates the AKT/AMPK/mTOR pathway, regulating EMT to promote ovarian cancer progression. Inhibiting this signaling axis might represent a potential therapeutic target for ovarian cancer.

Preclinical development and clinical studies of targeted JAK/STAT combined Anti-PD-1/PD-L1 therapy

Programmed cell death protein 1 (PD-1) binds to its ligand to help tumours evade the immune system and promote tumour progression. Although anti-PD-1/PD-L1 therapies show powerful effects in some patients, most patients are unable to benefit from this treatment due to treatment resistance. Therefore, it is important to overcome tumour resistance to PD-1/PD-L1 blockade. There is substantial evidence suggesting that the JAK/STAT signalling pathway plays a significant role in PD-1/PD-L1 expression and anti-PD-1/PD-L1 treatment. Herein, we describe the effects of the JAK/STAT signalling pathway on PD-1/PD-L1. Subsequently, the relationship between molecular mutations in the JAK/STAT signalling pathway and immune resistance was analysed. Finally, the latest advancements in drugs targeting the JAK/STAT pathway combined with PD1/PD-L1 inhibitors are summarised.

CALD1 facilitates epithelial-mesenchymal transition progression in gastric cancer cells by modulating the PI3K-Akt pathway

BACKGROUND

CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors, including gastric cancer (GC), and is associated with tumor progression and immune infiltration; however, the roles and mechanisms of CALD1 in epithelial-mesenchymal transition (EMT) in GC are unknown.

AIM

To investigate the role and mechanism of CALD1 in GC progression, invasion, and migration.

METHODS

In this study, the relationship between CALD1 and GC, as well as the possible network regulatory mechanisms of CALD1, was investigated by bioinformatics and validated by experiments. CALD1-siRNA was synthesized and used to transfect GC cells. Cell activity was measured using the CCK-8 method, cell migration and invasive ability were measured using wound healing assay and Transwell assay, and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot. A GC cell xenograft model was established to verify the results of in vitro experiments.

RESULTS

Bioinformatics results showed that CALD1 was highly expressed in GC tissues, and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC. The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression, and a prognostic model was constructed and evaluated. The experimental results were consistent with the results of the bioinformatics analysis. The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1, with the strongest expression found in AGS and MKN45 cells. Cell activity was significantly reduced after CALD1-siRNA transfection of AGS and MKN45 cells. The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection, and the related mRNA and protein expression was altered. According to bioinformatics findings in GC samples, the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway, and was closely related to the PI3K-Akt signaling pathway. Experimental validation revealed that upregulation of CALD1 increased the expression of PI3K, p-AKT, and p-mTOR, members of the PI3K-Akt pathway,while decreasing the expression of PTEN; PI3K-Akt inhibitor treatment decreased the expression of PI3K, p-AKT, and p-mTOR in cells overexpressing CALD1 (still higher than that in the normal group), but increased the expression of PTEN (still lower than that in the normal group). CCK-8 results revealed that the effect of CALD1 on tumor cell activity was decreased by the addition of the inhibitor. Scratch and Transwell experiments showed that the effect of CALD1 on tumor cell migration and invasion was weakened by the addition of the PI3K-Akt inhibitor. The mRNA and protein levels of EMT-related genes in AGS and MKN45 cells were greatly altered by the overexpression of CALD1, whereas the effect of overexpression of CALD1 was significantly weakened by the addition of the PI3K-Akt inhibitor. Animal experiments showed that tumour growth was slow after inhibition of CALD1, and the expression of some PI3K-Akt and EMT pathway proteins was altered.

CONCLUSION

Increased expression of CALD1 is a key factor in the progression, invasion, and metastasis of GC, which may be associated with regulating the PI3K-Akt pathway to promote EMT.

Hub biomarkers in ultrasound-guided bladder cancer and osteosarcoma: Myosin light chain kinase and caldesmon

Bladder cancer and osteosarcoma are 2 types of cancers that originate from epithelial tissues inside the bladder and bone or muscle tissues. Ultrasound-guided biopsies provide crucial support for the diagnosis and treatment of bladder cancer and osteosarcoma. However, the relationship between myosin light chain kinase (MYLK) and caldesmon (CALD1) and bladder cancer and osteosarcoma remains unclear. The bladder cancer datasets GSE65635 and GSE100926, the osteosarcoma dataset GSE39058, were obtained from gene expression omnibus. Differentially expressed genes (DEGs) were screened and weighted gene co-expression network analysis was performed. The construction and analysis of protein-protein interaction network, functional enrichment analysis, gene set enrichment analysis. Gene expression heat map was drawn and immune infiltration analysis was performed. The comparative toxicogenomics database analysis were performed to find disease most related to core gene. Western blotting experiments were performed. TargetScan screened miRNAs that regulated central DEGs. We obtained 54 DEGs. Functional enrichment analysis revealed significant enrichment in terms of cellular differentiation, cartilage development, skeletal development, muscle actin cytoskeleton, actin filament, Rho GTPase binding, DNA binding, fibroblast binding, MAPK signaling pathway, apoptosis, and cancer pathways. Gene set enrichment analysis indicated that DEGs were primarily enriched in terms of skeletal development, cartilage development, muscle actin cytoskeleton, MAPK signaling pathway, and apoptosis. The immune infiltration analysis showed that when T cells regulatory were highly expressed, Eosinophils exhibited a similar high expression, suggesting a strong positive correlation between T cells regulatory and Eosinophils, which might influence the disease progression in osteosarcoma. We identified 6 core genes (SRF, CTSK, MYLK, VCAN, MEF2C, CALD1). MYLK and CALD1 were significantly correlated with survival rate and exhibited lower expression in bladder cancer and osteosarcoma samples compared to normal samples. Comparative toxicogenomics database analysis results indicated associations of core genes with osteosarcoma, bladder tumors, bladder diseases, tumors, inflammation, and necrosis. The results of Western blotting showed that the expression levels of MYLK and CALD1 in bladder cancer and osteosarcoma were lower than those in normal tissues. MYLK and CALD1 likely play a role in regulating muscle contraction and smooth muscle function in bladder cancer and osteosarcoma. The lower expression of MYLK and CALD1 is associated with poorer prognosis.

MYLK and CALD1 as molecular targets in bladder cancer

Bladder cancer (BC) is a malignant tumor that occurs in bladder mucosa. However, relationship between myosin light chain kinase (MYLK) and CALD1 and BC remains unclear. The BC datasets GSE65635 and GSE100926 were downloaded from gene expression omnibus by GPL14951 and GPL14550. Multiple datasets were merged and batched. Differentially expressed genes (DEGs) were screened and weighted gene co-expression network analysis was performed. gene ontology (GO) and Kyoto Encyclopedia of Gene and Genome analysis, gene set enrichment analysis, immune infiltration analysis, survival analysis and Comparative Toxicogenomics Database were performed. TargetScan screened miRNAs that regulated central DEGs. 1026 DEGs were identified. According to GO analysis, DEGs were mainly enriched in cancer pathway, cGMP-PKG signaling pathway, Apelin signaling pathway and proteoglycans in cancer. The enrichment items are similar to GO and Kyoto Encyclopedia of Gene and Genome enrichment projects for DEGs, which were mainly enriched in cancer pathways and leukocyte trans-endothelial cell migration. Among enrichment projects of metascape, GO has regulation of the enzyme-linked receptor protein signaling pathway and silk-based process, as well as an enrichment network stained by enrichment terms and P values. Nine core genes (ACTA2, MYLK, MYH11, MYL9, ACTG2, TPM1, TPM2, TAGLN and CALD1) were obtained, which were highly expressed in tumor tissue samples and lowly expressed in normal tissue samples. Nine genes were associated with necrosis, inflammation, tumor, edema, and ureteral obstruction. MYLK and CALD1 are highly expressed in the BC. The higher expression of MYLK and CALD1, the worse prognosis.

MiR-1278 targets CALD1 and suppresses the progression of gastric cancer via the MAPK pathway

This study aimed to investigate the interaction between miR-1278 and Caldesmon (CALD1) in gastric cancer (GC) and the regulatory mechanism. In both GC cells and tissues, the levels of CALD1, miR-1278, migration-related markers (E-cadherin, N-cadherin, and Snail), and MAPK signaling pathway-related proteins were clarified using quantitative real-time PCR and western blotting analyses. The effects of miR-1278 and CALD1 on GC cell viability and migration were analyzed using CCK-8 and Transwell assays, respectively. The targeting effect of miR-1278 on CALD1 was investigated using bioinformatics prediction and a dual luciferase reporter assay. The effect of miR-1278 on tumor growth was estimated in vivo using a tumor xenograft assay. In GC, miR-1278 expression decreased, whereas CALD1 was highly expressed. Transfecting an miR-1278 mimic into cells inhibited the viability as well as migration of GC cells, and suppressed Ras, phosphorylated (p)-P38, and p-ERK1/2 protein levels. Moreover, miR-1278 targeted and negatively regulated CALD1 expression. CALD1 overexpression promoted GC cell survival and migration and activated the MAPK pathway. Treatment with an miR-1278 mimic partially rescued the changes caused by CALD1 overexpression. Overall, our study revealed that miR-1278 suppresses the malignant behavior of GC cells by targeting CALD1 and regulating the MAPK pathway.

Identification of two immune subtypes and four hub immune-related genes in ovarian cancer through multiple analysis

Immune classification of ovarian cancer (OV) becomes more and more influential for its immunotherapy. However, current studies had few immune subtypes of OV. It is urgent to explore the immune subtypes and deeper hub immune-related genes (IRGs) of OV for follow-up treatment. A total number of 379 OV samples were obtained from UCSC online website. Single sample gene set enrichment analysis of 29 immune gene sets was used for identifying immune subtypes of OV and gene set variation analysis were used for exploring the hallmarks and Kyoto Encyclopedia of Genes and Genomes pathways of immune types. Two immunity subtypes (Immunity_H and Immunity_L) were identified by single sample gene set enrichment analysis. The OV patients in Immunity_H group had longer overall survival compared with those in Immunity_L group. The Immunity_H had higher stromal score, immune score and estimate score and the tumor purity had the adverse tendency. Besides, the gene set variation analysis enrichment results showed positive relationship between improved immunoreaction and pathways correlated to classical signaling pathway (PI3K/AKT/MTOR, P53, TNFA/NFkB signaling pathways) and immune responses (T/B cell receptor signaling pathways and primary immunodeficiency). Furthermore, 4 hub IRGs (CCR5, IL10RA, ITGAL and PTPRC) were jointly dug by weighted gene co-expression network construction and Cytoscape. Our team also explored the mutations of 4 hub IRGs and PTPRC showed nearly 7% amplification. Besides, 8 immune-checkpoint genes had higher expression in Immuity_H group compared with Immuity_L group, except CD276. The correlation between PD-1/PD-L1 and 4 hub IRGs were explored and gene set enrichment analysis were conducted to explore the underlying mechanisms of PTPRC in OV. Finally, western-blotting showed PTPRC could regulate immune checkpoint PD-L1 expression via JAK-STAT signaling pathway. In a word, 2 immune subtypes and 4 hub IRGs of OV were identified by multiple analysis.

MTHFD2 promotes PD-L1 expression via activation of the JAK/STAT signalling pathway in bladder cancer

Although combination chemotherapy is widely used for bladder cancer (BC) treatment, the recurrence and progression rates remain high. Therefore, novel therapeutic targets are required. Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) contributes to tumourigenesis and immune evasion in several cancers; however, its biological function in BC remains unknown. This study aimed to investigate the expression, prognostic value and protumoural function of MTHFD2 in BC and elucidate the mechanism of programmed death-ligand 1 (PD-L1) upregulation by MTHFD2. An analysis using publicly available databases revealed that a high MTHFD2 expression was correlated with clinical features and a poor prognosis in BC. Furthermore, MTHFD2 promoted the growth, migration, invasion and tumourigenicity and decreased the apoptosis of BC cells in vivo and in vitro. The results obtained from databases showed that MTHFD2 expression was correlated with immune infiltration levels, PD-L1 expression, and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. The expression of MTHFD2, PD-L1 and JAK/STAT signalling pathway-related proteins increased after interferon gamma treatment and decreased after MTHFD2 knockdown. Moreover, addition of a JAK/STAT pathway activator partially reduced the effect of MTHFD2 knockdown on BC cells. Collectively, our findings suggest that MTHFD2 promotes the expression of PD-L1 through the JAK/STAT signalling pathway in BC.

Glucocorticoid receptor-induced non-muscle caldesmon regulates metastasis in castration-resistant prostate cancer

Lethal prostate cancer (PCa) is characterized by the presence of metastases and development of resistance to therapies. Metastases form in a multi-step process enabled by dynamic cytoskeleton remodeling. An actin cytoskeleton regulating gene, CALD1, encodes a protein caldesmon (CaD). Its isoform, low-molecular-weight CaD (l-CaD), operates in non-muscle cells, supporting the function of filaments involved in force production and mechanosensing. Several factors, including glucocorticoid receptor (GR), have been identified as regulators of l-CaD in different cell types, but the regulation of l-CaD in PCa has not been defined. PCa develops resistance in response to therapeutic inhibition of androgen signaling by multiple strategies. Known strategies include androgen receptor (AR) alterations, modified steroid synthesis, and bypassing AR signaling, for example, by GR upregulation. Here, we report that in vitro downregulation of l-CaD promotes epithelial phenotype and reduces spheroid growth in 3D, which is reflected in vivo in reduced formation of metastases in zebrafish PCa xenografts. In accordance, CALD1 mRNA expression correlates with epithelial-to-mesenchymal transition (EMT) transcripts in PCa patients. We also show that CALD1 is highly co-expressed with GR in multiple PCa data sets, and GR activation upregulates l-CaD in vitro. Moreover, GR upregulation associates with increased l-CaD expression after the development of resistance to antiandrogen therapy in PCa xenograft mouse models. In summary, GR-regulated l-CaD plays a role in forming PCa metastases, being clinically relevant when antiandrogen resistance is attained by the means of bypassing AR signaling by GR upregulation.

[Caldesmon and tumor growth: prospects for optimizing diagnosis and targeted therapy]

Tumor invasion plays a key role in the progression of tumors. This process is regulated by the interactions of cells and tissues, in which physical, cellular and molecular determinants undergo changes throughout the entire period of progression of tumor growth. Tumor invasion is triggered and maintained by specialized signal cascades that control the dynamic state of the cytoskeleton in tumor cells, the processes of rearrangement of cell-matrix and intercellular connections, followed by cell migration to neighboring tissues. Studying the mechanisms of regulation of cell motor activity and determining its main regulators is an important task for understanding the pathophysiology of tumor growth. Caldesmon is an actin, myosin and calmodulin binding protein. It is involved in the regulation of smooth muscle contraction by inhibiting actin and myosin binding, in the formation of actin stress fibers, and in the transport of intracellular granules. Currently, caldesmon is considered as a potential biomarker of tumor cell invasion, migration, and metastasis. The study of signaling molecules involved in tumor progression, such as caldesmon, is necessary to predict response to chemotherapy and radiotherapy. This review highlights the main functions of caldesmon and analyzes its role in oncological pathology.

(Nano)platforms in bladder cancer therapy: Challenges and opportunities

Urological cancers are among the most common malignancies around the world. In particular, bladder cancer severely threatens human health due to its aggressive and heterogeneous nature. Various therapeutic modalities have been considered for the treatment of bladder cancer although its prognosis remains unfavorable. It is perceived that treatment of bladder cancer depends on an interdisciplinary approach combining biology and engineering. The nanotechnological approaches have been introduced in the treatment of various cancers, especially bladder cancer. The current review aims to emphasize and highlight possible applications of nanomedicine in eradication of bladder tumor. Nanoparticles can improve efficacy of drugs in bladder cancer therapy through elevating their bioavailability. The potential of genetic tools such as siRNA and miRNA in gene expression regulation can be boosted using nanostructures by facilitating their internalization and accumulation at tumor sites and cells. Nanoparticles can provide photodynamic and photothermal therapy for ROS overgeneration and hyperthermia, respectively, in the suppression of bladder cancer. Furthermore, remodeling of tumor microenvironment and infiltration of immune cells for the purpose of immunotherapy are achieved through cargo-loaded nanocarriers. Nanocarriers are mainly internalized in bladder tumor cells by endocytosis, and proper design of smart nanoparticles such as pH-, redox-, and light-responsive nanocarriers is of importance for targeted tumor therapy. Bladder cancer biomarkers can be detected using nanoparticles for timely diagnosis of patients. Based on their accumulation at the tumor site, they can be employed for tumor imaging. The clinical translation and challenges are also covered in current review.

Emerging role of caldesmon in cancer: A potential biomarker for colorectal cancer and other cancers

Colorectal cancer (CRC) is a devastating disease, mainly because of metastasis. As a result, there is a need to better understand the molecular basis of invasion and metastasis and to identify new biomarkers and therapeutic targets to aid in managing these tumors. The actin cytoskeleton and actin-binding proteins are known to play an important role in the process of cancer metastasis because they control and execute essential steps in cell motility and contractility as well as cell division. Caldesmon (CaD) is an actin-binding protein encoded by the CALD1 gene as multiple transcripts that mainly encode two protein isoforms: High-molecular-weight CaD, expressed in smooth muscle, and low-molecular weight CaD (l-CaD), expressed in nonsmooth muscle cells. According to our comprehensive review of the literature, CaD, particularly l-CaD, plays a key role in the development, metastasis, and resistance to chemoradiotherapy in colorectal, breast, and urinary bladder cancers and gliomas, among other malignancies. CaD is involved in many aspects of the carcinogenic hallmarks, including epithelial mesenchymal transition via transforming growth factor-beta signaling, angiogenesis, resistance to hormonal therapy, and immune evasion. Recent data show that CaD is expressed in tumor cells as well as in stromal cells, such as cancer-associated fibroblasts, where it modulates the tumor microenvironment to favor the tumor. Interestingly, CaD undergoes selective tumor-specific splicing, and the resulting isoforms are generally not expressed in normal tissues, making these transcripts ideal targets for drug design. In this review, we will analyze these features of CaD with a focus on CRC and show how the currently available data qualify CaD as a potential candidate for targeted therapy in addition to its role in the diagnosis and prognosis of cancer.

mRNAsi-related metabolic risk score model identifies poor prognosis, immunoevasive contexture, and low chemotherapy response in colorectal cancer patients through machine learning

Colorectal cancer (CRC) is one of the most fatal cancers of the digestive system. Although cancer stem cells and metabolic reprogramming have an important effect on tumor progression and drug resistance, their combined effect on CRC prognosis remains unclear. Therefore, we generated a 21-gene mRNA stemness index-related metabolic risk score model, which was examined in The Cancer Genome Atlas and Gene Expression Omnibus databases (1323 patients) and validated using the Zhongshan Hospital cohort (200 patients). The high-risk group showed more immune infiltrations; higher levels of immunosuppressive checkpoints, such as CD274, tumor mutation burden, and resistance to chemotherapeutics; potentially better response to immune therapy; worse prognosis; and advanced stage of tumor node metastasis than the low-risk group. The combination of risk score and clinical characteristics was effective in predicting overall survival. Zhongshan cohort validated that high-risk score group correlated with malignant progression, worse prognosis, inferior adjuvant chemotherapy responsiveness of CRC, and shaped an immunoevasive contexture. This tool may provide a more accurate risk stratification in CRC and screening of patients with CRC responsive to immunotherapy.