CCL28 Downregulation Attenuates Pancreatic Cancer Progression Through Tumor Cell-Intrinsic and -Extrinsic Mechanisms

CCL28 promotes progression of hepatocellular carcinoma through PDGFD-regulated MMP9 and VEGFA pathways

Hepatocellular carcinoma (HCC) remains a major global health concern with limited therapeutic options and poor prognosis. Chemokines have emerged as critical regulators in the progression and metastasis of HCC. This study aims to investigate the mechanisms involved in CCL28-promoted progression of HCC and provide novel therapeutic targets for HCC treatment. Relationship between CCL28 expression and HCC progression were investigated by bioinformatic analysis and immunohistochemical staining assays. CCK-8, Transwell, and colony formation assay were conducted to explore the impact of CCL28 on the growth, migration and invasion of HCC cells. Quantitative real-time PCR and western blotting assays were performed to learn potential molecular mechanisms underlying the transformation of HCC driven by CCL28. The results showed that there was a direct link between increased CCL28 levels and the advancement of HCC, leading to a worse outcome. CCL28 significantly augmented malignant transformation of HCC cells, containing proliferation, migration, invasion, and clonogenicity, via activation of PDGFD-regulated MMP9 and VEGFA pathways. CCL28 emerges as a pivotal contributor to HCC tumorigenesis, propelling HCC development through the PDGFD signaling pathway. Our findings unveil potential therapeutic targets for HCC treatment.

Chemokine systems in oncology: From microenvironment modulation to nanocarrier innovations

Over the past few decades, significant strides have been made in understanding the pivotal roles that chemokine networks play in tumor biology. These networks, comprising chemokines and their receptors, wield substantial influence over cancer immune regulation and therapeutic outcomes. As a result, targeting these chemokine systems has emerged as a promising avenue for cancer immunotherapy. However, therapies targeting chemokines face significant challenges in solid tumor treatment, due to the complex and fragile of the chemokine networks. A nuanced comprehension of the complicacy and functions of chemokine networks, and their impact on the tumor microenvironment, is essential for optimizing their therapeutic utility in oncology. This review elucidates the ways in which chemokine networks interact with cancer immunity and tumorigenesis. We particularly elaborate on recent innovations in manipulating these networks for cancer treatment. The review also highlights future challenges and explores potential biomaterial strategies for clinical applications.

Single-Cell Sequencing Combined with Transcriptome Sequencing Constructs a Predictive Model of Key Genes in Multiple Sclerosis and Explores Molecular Mechanisms Related to Cellular Communication

Background

Multiple sclerosis (MS) causes chronic inflammation and demyelination of the central nervous system and comprises a class of neurodegenerative diseases in which interactions between multiple immune cell types mediate the involvement of MS development. However, the early diagnosis and treatment of MS remain challenging.

Methods

Gene expression profiles of MS patients were obtained from the Gene Expression Omnibus (GEO) database. Single-cell and intercellular communication analyses were performed to identify candidate gene sets. Predictive models were constructed using LASSO regression. Relationships between genes and immune cells were analyzed by single sample gene set enrichment analysis (ssGSEA). The molecular mechanisms of key genes were explored using gene enrichment analysis. An miRNA network was constructed to search for target miRNAs related to key genes, and related transcription factors were searched by transcriptional regulation analysis. We utilized the GeneCard database to detect the correlations between disease-regulated genes and key genes. We verified the mRNA expression of 4 key genes by reverse transcription-quantitative PCR (RT‒qPCR).

Results

Monocyte marker genes were selected as candidate gene sets. CD3D, IL2RG, MS4A6A, and NCF2 were found to be the key genes by LASSO regression. We constructed a prediction model with AUC values of 0.7569 and 0.719. The key genes were closely related to immune factors and immune cells. We explored the signaling pathways and molecular mechanisms involving the key genes by gene enrichment analysis. We obtained and visualized the miRNAs associated with the key genes using the miRcode database. We also predicted the transcription factors involved. We used validated key genes in MS patients, several of which were confirmed by RT‒qPCR.

Conclusion

The prediction model constructed with the CD3D, IL2RG, MS4A6A, and NCF2 genes has good diagnostic efficacy and provides new ideas for the diagnosis and treatment of MS.

The Value of CXCL1, CXCL2, CXCL3, and CXCL8 as Potential Prognosis Markers in Cervical Cancer: Evidence of E6/E7 from HPV16 and 18 in Chemokines Regulation

Cervical cancer (CC) is a serious global health issue, and it is well-known that HPV infection is the main etiological factor that triggers carcinogenesis. In cancer, chemokine ligands and receptors are involved in tumor cell growth, metastasis, leukocyte infiltration, and angiogenesis; however, information on the role played by E6/E7 of HPV16/18 in the modulation of chemokines is very limited. Therefore, this study aimed to determine whether chemokines are differentially expressed in CC-derived cell lines; if E6/E7 oncoproteins from HPV16 and 18 are capable of mediating chemokine expression, what is the expression profile of chemokines in tissues derived from CC and what is their impact on the overall survival of patients with this pathology? For this purpose, RNA sequencing and real-time PCR were performed on SiHa, HeLa, and C33A tumorigenic cell lines, on the non-tumorigenic HaCaT cells, and the E6/E7 HPV-transduced HaCaT cell models. Furthermore, chemokine expression and survival analysis were executed on 304 CC and 22 normal tissue samples from The Cancer Genome Atlas (TCGA) repository. The results demonstrate that CXCL1, CXCL2, CXCL3, and CXCL8 are regulated by E6/E7 of HPV16 and 18, are overexpressed in CC biopsies, and that their higher expression is related to a worse prognostic survival.

RBPJ Deficiency Sensitizes Pancreatic Acinar Cells to KRAS-Mediated Pancreatic Intraepithelial Neoplasia Initiation

BACKGROUND AND AIMS

Development of pancreatic ductal adenocarcinoma (PDAC) is a multistep process intensively studied; however, precocious diagnosis and effective therapy still remain unsatisfactory. The role for Notch signaling in PDAC has been discussed controversially, as both cancer-promoting and cancer-antagonizing functions have been described. Thus, an improved understanding of the underlying molecular mechanisms is necessary. Here, we focused on RBPJ, the receiving transcription factor in the Notch pathway, examined its expression pattern in PDAC, and characterized its function in mouse models of pancreatic cancer development and in the regeneration process after acute pancreatitis.

METHODS

Conditional transgenic mouse models were used for functional analysis of RBPJ in the adult pancreas, initiation of PDAC precursor lesions, and pancreatic regeneration. Pancreata and primary acinar cells were tested for acinar-to-ductal metaplasia together with immunohistology and comprehensive transcriptional profiling by RNA sequencing.

RESULTS

We identified reduced RBPJ expression in a subset of human PDAC specimens. Ptf1α-CreERT-driven depletion of RBPJ in transgenic mice revealed that its function is dispensable for the homeostasis and maintenance of adult acinar cells. However, primary RBPJ-deficient acinar cells underwent acinar-to-ductal differentiation in ex vivo. Importantly, oncogenic KRAS expression in the context of RBPJ deficiency facilitated the development of pancreatic intraepithelial neoplasia lesions with massive fibrotic stroma formation. Interestingly, RNA-sequencing data revealed a transcriptional profile associated with the cytokine/chemokine and extracellular matrix changes. In addition, lack of RBPJ delays the course of acute pancreatitis and critically impairs it in the context of KRASG12D expression.

CONCLUSIONS

Our findings imply that downregulation of RBPJ in PDAC patients derepresses Notch targets and promotes KRAS-mediated pancreatic acinar cells transformation and desmoplasia development.

Chromatin accessibility uncovers KRAS-driven FOSL2 promoting pancreatic ductal adenocarcinoma progression through up-regulation of CCL28

BACKGROUND

The epigenetic mechanisms involved in the progression of pancreatic ductal adenocarcinoma (PDAC) remain largely unexplored. This study aimed to identify key transcription factors (TFs) through multiomics sequencing to investigate the molecular mechanisms of TFs that play critical roles in PDAC.

METHODS

To characterise the epigenetic landscape of genetically engineered mouse models (GEMMs) of PDAC with or without KRAS and/or TP53 mutations, we employed ATAC-seq, H3K27ac ChIP-seq, and RNA-seq. The effect of Fos-like antigen 2 (FOSL2) on survival was assessed using the Kaplan-Meier method and multivariate Cox regression analysis for PDAC patients. To study the potential targets of FOSL2, we performed Cleavage Under Targets and Tagmentation (CUT&Tag). To explore the functions and underlying mechanisms of FOSL2 in PDAC progression, we employed several assays, including CCK8, transwell migration and invasion, RT-qPCR, Western blotting analysis, IHC, ChIP-qPCR, dual-luciferase reporter, and xenograft models.

RESULTS

Our findings indicated that epigenetic changes played a role in immunosuppressed signalling during PDAC progression. Moreover, we identified FOSL2 as a critical regulator that was up-regulated in PDAC and associated with poor prognosis in patients. FOSL2 promoted cell proliferation, migration, and invasion. Importantly, our research revealed that FOSL2 acted as a downstream target of the KRAS/MAPK pathway and recruited regulatory T (Treg) cells by transcriptionally activating C-C motif chemokine ligand 28 (CCL28). This discovery highlighted the role of an immunosuppressed regulatory axis involving KRAS/MAPK-FOSL2-CCL28-Treg cells in the development of PDAC.

CONCLUSION

Our study uncovered that KRAS-driven FOSL2 promoted PDAC progression by transcriptionally activating CCL28, revealing an immunosuppressive role for FOSL2 in PDAC.

Fragment-based drug discovery of small molecule ligands for the human chemokine CCL28

The mucosal chemokine CCL28 is a promising target for immunotherapy drug development due to its elevated expression level in epithelial cells and critical role in creating and maintaining an immunosuppressive tumor microenvironment. Using sulfotyrosine as a probe, NMR chemical shift mapping identified a potential receptor-binding hotspot on the human CCL28 surface. CCL28 was screened against 2,678 commercially available chemical fragments by 2D NMR, yielding thirteen verified hits. Computational docking predicted that two fragments could occupy adjoining subsites within the sulfotyrosine recognition cleft. Dual NMR titrations confirmed their ability to bind CCL28 simultaneously, thereby validating an initial fragment pair for linking and merging strategies to design high-potency CCL28 inhibitors.