Overexpression of DDR1 Promotes Migration, Invasion, Though EMT-Related Molecule Expression and COL4A1/DDR1/MMP-2 Signaling Axis

Emerging strategies and translational advancements of DDR1 in oncology

Discoidin domain receptor 1 (DDR1) has emerged as a promising therapeutic target in oncology due to its unique role in tumor-stroma interactions and its involvement in key signaling pathways that drive cancer progression. DDR1 is homologous to the transmembrane receptor tyrosine kinase (RTK) family and uniquely requires binding to collagen for its activation. It regulates several cellular processes related to tumor cell proliferation, metabolism, migration, stromal remodeling, and epithelial-mesenchymal transition (EMT), ultimately influencing patient survival. Dysregulation of DDR1 may contribute to cancer progression, neurodegenerative diseases, fibrotic conditions, and atherosclerosis. Moreover, DDR1 has been shown to affect a wide variety of cancers, including lung, breast, stomach, colon, ovarian, and pancreatic cancers, underscoring its potential as a therapeutic target. Various small-molecule tyrosine kinase inhibitors aimed at DDR1 have been developed and have demonstrated significant effectiveness in reducing tumor growth. This review focuses on the structure, function, and mechanism of DDR1, as well as its involvement in cancer progression. Additionally, it examines the development and therapeutic potential of DDR1 inhibitors, offering a comprehensive overview of their application in cancer treatment. By synthesizing current knowledge, this article provides valuable insights to guide future research and innovation in targeting DDR1 for clinical therapeutic advancement.

DDR1 Targeting HOXA6 Facilitates Bladder Cancer Progression via Inhibiting Ferroptosis

Ferroptosis is an important factor affecting the progression of bladder cancer (BC). Previous studies have confirmed that discoidin domain receptor 1 (DDR1) promotes BC progression. However, the regulatory mechanisms of BC ferroptosis are largely unknown. Therefore, this study aimed to investigate the regulatory effects of DDR1 on BC cell ferroptosis. Ferroptosis-sensitive and -resistant BC cells were screened, and reverse-transcription quantitative PCR and western blotting were used to determine the expression of DDR1 in BC cells. In vitro and in vivo assays were performed to analyse the mechanisms of DDR1 in BC ferroptosis. The ferroptosis inducer erastin inhibited DDR1 expression in TCCSUP cells. The ferroptosis inhibitor ferrostatin-1 inhibited BC cell death caused by DDR1 knockdown. DDR1 increased glutathione, glutathione peroxidase 4 and solute carrier family 7 member 11 expression, while decreasing malondialdehyde and Fe2+ levels and acyl-CoA synthetase long-chain family member 4 levels and inhibiting epithelial mesenchymal transition and neurofibromin 2-yes-associated protein. These effects were abrogated by the knockdown of homeobox A6 (HOXA6). DDR1 targeting of HOXA6 facilitated BC growth and inhibited BC ferroptosis in vivo. DDR1 promotes BC progression by inhibiting ferroptosis and targeting HOXA6. Thus, DDR1 may serve as a potential therapeutic target for BC.

Super-resolution imaging reveals the role of DDR1 cluster in NSCLC proliferation

Discoidin domain receptor 1 (DDR1), a transmembrane protein, is crucial in tumor development. Prior studies have demonstrated a significant correlation between protein cluster distribution on the cell membrane and tumor evolution. However, the precise spatial distribution characteristics of DDR1 on cell membranes and their impact on tumor development remain unclear. In this study, we conducted gene expression analysis to investigate DDR1 expression in non-small cell lung cancer (NSCLC) and its association with patient prognosis. We also employed direct stochastic optical reconstruction microscopy (dSTORM) imaging to examine DDR1's spatial distribution in NSCLC cells and tissues. Our findings indicate that DDR1 forms larger, tighter, and more abundant clusters in cancer cells and tissues compared to their normal counterparts. Notably, we observed that the enhanced aggregation of DDR1 clusters increased the likelihood of interaction with SRC, thereby activating the SRC-STAT3 signaling pathway in NSCLC cells and promoting cell proliferation. This study provides novel insights into the role of DDR1 aggregation in tumor proliferation, confirms DDR1 as a potential tumor marker, and serves as a valuable resource for future drug development.

The role of DDR1 in cancer and the progress of its selective inhibitors

Discoidin domain receptor 1 (DDR1) is a member of the receptor tyrosine kinase superfamily, which mainly activates downstream signaling pathways through binding to collagen. The abnormal expression of DDR1 is closely related to the occurrence and development of various tumors, and it is one of the potential targets for molecular targeted therapy. At present, specific antibodies and selective small molecule inhibitors against DDR1 have been approved for Phase I clinical trials. In this review, we summarized the effects of DDR1 on tumor cell proliferation, survival, migration, invasion, energy metabolism and tumor microenvironment, and combed the research progress of selective DDR1 small molecule inhibitors in the field of anti-tumor. It is hoped that more DDR1 inhibitors with excellent performance will be developed to provide more treatment options for tumor patients.

DDR1 promotes metastasis of cervical cancer and downstream phosphorylation signal via binding GRB2

Cervical cancer is a leading cause of cancer-related death among women and its recurrence and metastasis poses challenges to treatment. Discoidin domain receptor 1 (DDR1) was associated with cellular migration and invasion in several types of cancers. However, its function in cervical cancer is still unclear. In this study, we found that DDR1 was significantly more expressed in cervical cancer samples than in normal tissues. SRY-Box transcription factor 2 (SOX2), a known oncogene in cervical cancer, showed a positive correlation with DDR1 and regulated DDR1 transcription, contributing to the elevated expression of DDR1 in cervical cancer. Regarding the function of DDR1 in cervical cancer, the overexpression of DDR1 caused an increase in the migration, invasion, and epithelial-mesenchymal transition (EMT) of cervical cancer cells. In contrast, cervical cancer cells with reduced DDR1 expression exhibited a lower migration rate, fewer invasive cells, and decreased levels of EMT markers. In vivo, mice injected with cervical cancer cells with overexpressed DDR1 showed more pulmonary metastasis and nodule number. Opposite results were found in mice injected with DDR1 silenced cervical cancer cells. Since DDR1 can cause phosphorylation of downstream targets, a phosphorylation omics was employed to reveal the downstream targets of DDR1, including eukaryotic translation initiation factor 4E binding protein 1 and EPH receptor A2. Furthermore, DDR1 bound directly with Src homology 2 domain of growth factor receptor bound protein 2 (GRB2) which mediated the function of DDR1 in the malignant behaviors of cervical cancer and the phosphorylation of downstream targets. In conclusion, DDR1 binds directly to GRB2 and then affects downstream phosphorylation signals, ultimately exacerbating the metastasis of cervical cancer cells. This work sheds light on the mechanism by which DDR1 functions in cervical cancer cells, providing therapeutic strategy for the treatment of cervical cancer.

Integrating network analysis with differential expression to uncover therapeutic and prognostic biomarkers in esophageal squamous cell carcinoma

Introduction: Esophageal squamous cell carcinoma (ESCC) accounts for over 90% of all esophageal tumors. However, the molecular mechanism underlying ESCC development and prognosis remains unclear, and there are still no effective molecular biomarkers for diagnosing or predicting the clinical outcome of patients with ESCC. Here, we used bioinformatics analysis to identify potential biomarkers and therapeutic targets for ESCC. Methodology: Differentially expressed genes (DEGs) between ESCC and normal esophageal tissue samples were obtained by comprehensively analyzing publicly available RNA-seq datasets from the TCGA and GTEX. Gene Ontology (GO) annotation and Reactome pathway analysis identified the biological roles of the DEGs. Moreover, the Cytoscape 3.10.1 platform and subsidiary tools such as CytoHubba were used to visualize the DEGs' protein-protein interaction (PPI) network and identify hub genes, Furthermore our results are validated by using Single-cell RNA analysis. Results: Identification of 2524 genes exhibiting altered expression enriched in pathways including keratinization, epidermal cell differentiation, G alpha(s) signaling events, and biological process of cell proliferation and division, extracellular matrix (ECM) disassembly, and muscle function. Moreover, upregulation of hallmarks E2F targets, G2M checkpoints, and TNF signaling. CytoHubba revealed 20 hub genes that had a valuable influence on the progression of ESCC in these patients. Among these, the high expression levels of four genes, CDK1 MAD2L1, PLK1, and TOP2A, were associated with critical dependence for cell survival in ESCC cell lines, as indicated by CRISPR dependency scores, gene expression data, and cell line metadata. We also identify the molecules targeting these essential hub genes, among which GSK461364 is a promising inhibitor of PLK1, BMS265246, and Valrubicin inhibitors of CDK1 and TOP2A, respectively. Moreover, we identified that elevated expression of MMP9 is associated with worse overall survival in ESCC patients, which may serve as potential prognostic biomarker or therapeutic target for ESCC. The single-cell RNA analysis showed MMP9 is highly expressed in myeloid, fibroblast, and epithelial cells, but low in T cells, endothelial cells, and B cells. This suggests MMP9's role in tumor progression and matrix remodeling, highlighting its potential as a prognostic marker and therapeutic target. Discussion: Our study identified key hub genes in ESCC, assessing their potential as therapeutic targets and biomarkers through detailed expression and dependency analyses. Notably, MMP9 emerged as a significant prognostic marker with high expression correlating with poor survival, underscoring its potential for targeted therapy. These findings enhance our understanding of ESCC pathogenesis and highlight promising avenues for treatment.

A network map of discoidin domain receptor 1(DDR1)-mediated signaling in pathological conditions

Discoidin domain receptor 1 (DDR1) is one of the receptors that belong to a family of non-integrin collagen receptors. In common, DDR1 is predominantly found in epithelial and smooth muscle cells and its mainly involved in organogenesis during embryonic development. However, it's also overexpressed in several pathological conditions, including cancer and inflammation. The DDR1 is reported in numerous cancers, including breast, prostate, pancreatic, bladder, lung, liver, pituitary, colorectal, skin, gastric, glioblastoma, and inflammation. DDR1 activates through the collagen I, IV, IGF-1/IGF1R, and IGF2/IR, regulating downstream signaling molecules such as MAPKs, PI3K/Akt, and NF-kB in diseases. Despite its biomedical importance, there is a lack of consolidated network map of the DDR1 signaling pathway, which prompted us for curation of literature data pertaining to the DDR1 system following the NetPath criteria. We present here the compiled pathway map comprises 39 activation/inhibition events, 17 catalysis events, 22 molecular associations, 65 gene regulation events, 35 types of protein expression, and two protein translocation events. The detailed DDR1 signaling pathway map is made freely accessible through the WikiPathways Database ( https://www.wikipathways.org/index.php/ Pathway: https://www.wikipathways.org/index.php/Pathway:WP5288 ).

Identification and validation of biomarkers for epithelial-mesenchymal transition-related cells to estimate the prognosis and immune microenvironment in primary gastric cancer by the integrated analysis of single-cell and bulk RNA sequencing data

BACKGROUND

The epithelial-mesenchymal transition (EMT) is associated with gastric cancer (GC) progression and immune microenvironment. To better understand the heterogeneity underlying EMT, we integrated single-cell RNA-sequencing (scRNA-seq) data and bulk sequencing data from GC patients to evaluate the prognostic utility of biomarkers for EMT-related cells (ERCs), namely, cancer-associated fibroblasts (CAFs) and epithelial cells (ECs).

METHODS

scRNA-seq data from primary GC tumor samples were obtained from the Gene Expression Omnibus (GEO) database to identify ERC marker genes. Bulk GC datasets from the Cancer Genome Atlas (TCGA) and GEO were used as training and validation sets, respectively. Differentially expressed markers were identified from the TCGA database. Univariate Cox, least-absolute shrinkage, and selection operator regression analyses were performed to identify EMT-related cell-prognostic genes (ERCPGs). Kaplan-Meier, Cox regression, and receiver-operating characteristic (ROC) curve analyses were adopted to evaluate the prognostic utility of the ERCPG signature. An ERCPG-based nomogram was constructed by integrating independent prognostic factors. Finally, we evaluated the correlations between the ERCPG signature and immune-cell infiltration and verified the expression of ERCPG prognostic signature genes by in vitro cellular assays.

RESULTS

The ERCPG signature was comprised of seven genes (COL4A1, F2R, MMP11, CAV1, VCAN, FKBP10, and APOD). Patients were divided into high- and low-risk groups based on the ERCPG risk scores. Patients in the high-risk group showed a poor prognosis. ROC and calibration curves suggested that the ERCPG signature and nomogram had a good prognostic utility. An immune cell-infiltration analysis suggested that the abnormal expression of ERCPGs induced the formation of an unfavorable tumor immune microenvironment. In vitro cellular assays showed that ERCPGs were more abundantly expressed in GC cell lines compared to normal gastric tissue cell lines.

CONCLUSIONS

We constructed and validated an ERCPG signature using scRNA-seq and bulk sequencing data from ERCs of GC patients. Our findings support the estimation of patient prognosis and tumor treatment in future clinical practice.

New target DDR1: A "double-edged sword" in solid tumors

Globally, cancer is a major catastrophic disease that seriously threatens human health. Thus, there is an urgent need to find new strategies to treat cancer. Among them, identifying new targets is one of the best ways to treat cancer at present. Especially in recent years, scientists have discovered many new targets and made breakthroughs in the treatment of cancer, bringing new hope to cancer patients. As one of the novel targets for cancer treatment, DDR1 has attracted much attention due to its unique role in cancer. Hence, here, we focus on a new target, DDR1, which may be a "double-edged sword" of human solid tumors. In this review, we provide a comprehensive overview of how DDR1 acts as a "double-edged sword" in cancer. First, we briefly introduce the structure and normal physiological function of DDR1; Second, we delineate the DDR1 expression pattern in single cells; Next, we sorte out the relationship between DDR1 and cancer, including the abnormal expression of DDR1 in cancer, the mechanism of DDR1 and cancer occurrence, and the value of DDR1 on cancer prognosis. In addition, we introduced the current status of global drug and antibody research and development targeting DDR1 and its future design prospects; Finally, we summarize and look forward to designing more DDR1-targeting drugs in the future to make further progress in the treatment of solid tumors.

Discoidin domain receptor 1 may be involved in biological barrier homeostasis

WHAT IS KNOWN AND OBJECTIVE

Discoidin domain receptor 1 (DDR1) is a receptor tyrosine kinase involved in the pathological processes of several diseases, such as keloid formation, renal fibrosis, atherosclerosis, tumours, and inflammatory processes. The biological barrier is the first line of defence against pathogens, and its disruption is closely related to diseases. In this review, we attempt to elucidate the relationship between DDR1 and the biological barrier, explore the potential biological value of DDR1, and review the current research status and clinical potential of DDR1-selective inhibitors.

METHODS

We conducted an extensive literature search on PubMed to collect studies on the relevance of DDR1 to biological barriers and DDR1-selective inhibitors. With these studies, we explored the relationship between DDR1 and biological barriers and briefly reviewed representative DDR1-selective inhibitors that have been reported in recent years.

RESULTS AND DISCUSSION

First, the review of the potential mechanisms by which DDR1 regulates biological barriers, including the epithelial, vascular, glomerular filtration, blood-labyrinth, and blood-brain barriers. In the body, DDR1 dysfunction and aberrant expression may be involved in the homeostasis of the biological barrier. Secondly, the review of DDR1 inhibitors reported in recent years shows that DDR1-targeted inhibition is an attractive and promising pharmacological intervention.

WHAT IS NEW AND CONCLUSIONS

This review shows that DDR1 is involved in various physiological and pathological processes and in the regulation of biological barrier homeostasis. However, studies on DDR1 and biological barriers are still scarce, and further studies are needed to elucidate their specific mechanisms. The development of targeted inhibitors provides a new direction and idea to study the mechanism of DDR1.

Collagen Remodeling along Cancer Progression Providing a Novel Opportunity for Cancer Diagnosis and Treatment

The extracellular matrix (ECM) is a significant factor in cancer progression. Collagens, as the main component of the ECM, are greatly remodeled alongside cancer development. More and more studies have confirmed that collagens changed from a barrier to providing assistance in cancer development. In this course, collagens cause remodeling alongside cancer progression, which in turn, promotes cancer development. The interaction between collagens and tumor cells is complex with biochemical and mechanical signals intervention through activating diverse signal pathways. As the mechanism gradually clears, it becomes a new target to find opportunities to diagnose and treat cancer. In this review, we investigated the process of collagen remodeling in cancer progression and discussed the interaction between collagens and cancer cells. Several typical effects associated with collagens were highlighted in the review, such as fibrillation in precancerous lesions, enhancing ECM stiffness, promoting angiogenesis, and guiding invasion. Then, the values of cancer diagnosis and prognosis were focused on. It is worth noting that several generated fragments in serum were reported to be able to be biomarkers for cancer diagnosis and prognosis, which is beneficial for clinic detection. At a glance, a variety of reported biomarkers were summarized. Many collagen-associated targets and drugs have been reported for cancer treatment in recent years. The new targets and related drugs were discussed in the review. The mass data were collected and classified by mechanism. Overall, the interaction of collagens and tumor cells is complicated, in which the mechanisms are not completely clear. A lot of collagen-associated biomarkers are excavated for cancer diagnosis. However, new therapeutic targets and related drugs are almost in clinical trials, with merely a few in clinical applications. So, more efforts are needed in collagens-associated studies and drug development for cancer research and treatment.

Discoidin Domain Receptor 1, a Potential Biomarker and Therapeutic Target in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is still one of the most lethal human cancers in the world due to its high degree of malignancy, easy invasion and metastasis, poor therapeutic effect and poor prognosis. Nowadays, there is no very effective diagnosis and treatment method. It is crucial to elucidate the underlying pathogenesis and mechanisms of HCC for developing new and effective diagnostic/prognostic biomarkers and therapies. Discoidin domain receptors (DDRs) belong to the family of transmembrane receptor tyrosine kinases (RTKs) and are recognized as playing central regulatory roles in a variety of high incidence human diseases, including tumors. DDRs have two members, DDR1 and DDR2. The role of DDR1 in several tumors has been extensively studied, and many researchers have identified it as a powerful candidate target for the development of functional and effective tumor treatment inhibitors. However, its role and mechanism in HCC are ill defined. In this article, we review the advanced insights into the progression of DDR1 in HCC, particularly the ligands and mechanisms in invasion and metastasis, which may open new avenues for the therapeutic utility of HCC.

Data mining-based study of collagen type III alpha 1 (COL3A1) prognostic value and immune exploration in pan-cancer

The extracellular matrix (ECM) shows an essential effect during the occurrence and procession of human cancers. Type III collagen is a crucial component of ECM. Collagen Type III Alpha 1(COL3A1) is aberrantly expressed in a variety of cancers. Nevertheless, the role of COL3A1 in pan-cancer stays unidentified. In this study, we explored public databases, including Cancer Genome Atlas (TCGA), GTEx, GEPIA, cBioPortal, Oncommine, TIMER and GENEMANIA databases to identify the differential expression of COL3A1 in human cancer tissues and normal samples, followed by its prognostic value for patient survival. In addition, we explore the association between COL3A1 expression and immune infiltration. Further, we used the GeneMANIA database and Gene Set Enrichment Analysis (GSEA) to investigate Protein–Protein Interaction (PPI) and gene functional enrichment. Results show that COL3A1 expressed higher in tumor samples than in normal samples. Upregulation of COL3A1 is associated with a worse prognosis and a more advanced cancer stage. COL3A1 expression shows significant positive correlations with tumor-infiltrating immune cells (TIICs), including neutrophils, macrophages, CD8 + T cells, CD4 + T cells, dendritic cells, and B cells. Markers of TIICs demonstrated distinct patterns of COL3A1-related immune infiltration. COL3A1 expression was associated with ECM receptor interaction, regulation of actin cytoskeleton and focal adhesion pathways via GSEA analysis. In conclusion, COL3A1 may be a molecular biomarker for prognosis and immune infiltration in pan-cancer. It might act as a potential target for a new insight of human cancers management.

DDR1 Affects Metabolic Reprogramming in Breast Cancer Cells by Cross-Talking to the Insulin/IGF System

The insulin receptor isoform A (IR-A), a dual receptor for insulin and IGF2, plays a role in breast cancer (BC) progression and metabolic reprogramming. Notably, discoidin domain receptor 1 (DDR1), a collagen receptor often dysregulated in cancer, is involved in a functional crosstalk and feed forward loop with both the IR-A and the insulin like growth factor receptor 1 (IGF1R). Here, we aimed at investigating whether DDR1 might affect BC cell metabolism by modulating the IGF1R and/or the IR. To this aim, we generated MCF7 BC cells engineered to stably overexpress either IGF2 (MCF7/IGF2) or the IR-A (MCF7/IR-A). In both cell models, we observed that DDR1 silencing induced a significant decrease of total ATP production, particularly affecting the rate of mitochondrial ATP production. We also observed the downregulation of key molecules implicated in both glycolysis and oxidative phosphorylation. These metabolic changes were not modulated by DDR1 binding to collagen and occurred in part in the absence of IR/IGF1R phosphorylation. DDR1 silencing was ineffective in MCF7 knocked out for DDR1. Taken together, these results indicate that DDR1, acting in part independently of IR/IGF1R stimulation, might work as a novel regulator of BC metabolism and should be considered as putative target for therapy in BC.

Complex roles of discoidin domain receptor tyrosine kinases in cancer

Discoidin domain receptors, DDR1 and DDR2 are members of the receptor tyrosine kinase (RTK) family that serves as a non-integrin collagen receptor and were initially identified as critical regulators of embryonic development and cellular homeostasis. In recent years, numerous studies have focused on the role of these receptors in disease development, in particular, cancer where they have been reported to augment ECM remodeling, invasion, drug resistance to facilitate tumor progression and metastasis. Interestingly, accumulating evidence also suggests that DDRs promote apoptosis and suppress tumor progression in various human cancers due to which their functions in cancer remain ill-defined and presents a case of an interesting therapeutic target. The present review has discussed the role of DDRs in tumorigenesis and the metastasis.