Targeting epiregulin in the treatment-damaged tumor microenvironment restrains therapeutic resistance

Functionalizing tetrahedral framework nucleic acids-based nanostructures for tumor in situ imaging and treatment

Timely in situ imaging and effective treatment are efficient strategies in improving the therapeutic effect and survival rate of tumor patients. In recent years, there has been rapid progress in the development of DNA nanomaterials for tumor in situ imaging and treatment, due to their unsurpassed structural stability, excellent material editability, excellent biocompatibility and individual endocytic pathway. Tetrahedral framework nucleic acids (tFNAs), are a typical example of DNA nanostructures demonstrating superior stability, biocompatibility, cell-entry performance, and flexible drug-loading ability. tFNAs have been shown to be effective in achieving timely tumor in situ imaging and precise treatment. Therefore, the progress in the fabrication, characterization, modification and cellular internalization pathway of tFNAs-based functional systems and their potential in tumor in situ imaging and treatment applications were systematically reviewed in this article. In addition, challenges and future prospects of tFNAs in tumor in situ imaging and treatment as well as potential clinical applications were discussed.

Diffuse tumors: Molecular determinants shared by different cancer types

Most cancer types have both diffuse and non-diffuse subtypes, which have rather distinct morphologies, namely scattered tiny tumors vs. one solid tumor, and different levels of aggressiveness. However, the causes for forming such distinct subtypes remain largely unknown. Using the diffuse and non-diffuse gastric cancers (GCs) as the illustrative example, we present a computational study based on the transcriptomic data from the TCGA and GEO databases, to address the following questions: (i) What are the key molecular determinants that give rise to the distinct morphologies between diffuse and non-diffuse cancers? (ii) What are the main reasons for diffuse cancers to be generally more aggressive than non-diffuse ones of the same cancer type? (iii) What are the reasons for their distinct immunoactivities? And (iv) why do diffuse cancers on average tend to take place in younger patients? The study is conducted using the framework we have previously developed for elucidation of general drivers cancer formation and development. Our main discoveries are: (a) the level of (poly-) sialic acids deployed on the surface of cancer cells is a significant factor contributing to questions (i) and (ii); (b) poly-sialic acids synthesized by ST8SIA4 are the key to question (iii); and (c) the circulating growth factors specifically needed by the diffuse subtype dictate the answer to question (iv). All these predictions are substantiated by published experimental studies. Our further analyses on breast, prostate, lung, liver, and thyroid cancers reveal that these discoveries generally apply to the diffuse subtypes of these cancer types, hence indicating the generality of our discoveries.

Epiregulin: A new prognostic molecule in non-Hodgkin lymphoma

BACKGROUND

Epiregulin is a molecule that plays a role in cell proliferation, tumor development, inflammation, and angiogenesis in malignant diseases.

AIM

Our study aims to reveal, for the first time, the predictive value of this molecule in non-Hodgkin lymphoma (NHL) and its association with disease stage, cell type, and extranodal involvement.

METHODS

The study is an observational case-control trial involving 60 newly diagnosed NHL patients and 60 healthy individuals (control group) between 18 and 75 years old. Demographic characteristics of all volunteers, stages of patients' illnesses and lymphoma cell types, hemogram, biochemistry tests, beta 2-microglobulin, C-reactive protein (CRP), and epiregulin levels were measured and statistically evaluated.

RESULTS

Epiregulin levels were significantly higher in NHL patients compared to the control group (P < 0.0001). Similarly, a significant increase in epiregulin levels was observed in advanced NHL patients. Furthermore, the most common NHL subgroup within the NHL group, diffuse Large B Cell Lymphoma (DLBCL), and the subgroup with extranodal involvement also had significantly higher levels of epiregulin. A positive correlation was found between the epiregulin molecule and CRP, beta 2-microglobulin, and lactate dehydrogenase (LDH) levels in NHL patients.

CONCLUSION

Our study suggests that serum epiregulin levels, discovered to increase in NHL patients for the first time, may be an independent predictive molecule in an advanced stage, extranodal involvement, and the DLBCL subtype of this disease. Epiregulin positively correlates with prognostic molecules such as beta 2-microglobulin, LDH, and CRP. Illuminating its potential role in NHL pathogenesis could make epiregulin a vital drug target for treatment.

Immune cell senescence and exhaustion promote the occurrence of liver metastasis in colorectal cancer by regulating epithelial-mesenchymal transition

BACKGROUND

Liver metastasis (LM) stands as a primary cause of mortality in metastatic colorectal cancer (mCRC), posing a significant impediment to long-term survival benefits from targeted therapy and immunotherapy. However, there is currently a lack of comprehensive investigation into how senescent and exhausted immune cells contribute to LM.

METHODS

We gathered single-cell sequencing data from primary colorectal cancer (pCRC) and their corresponding matched LM tissues from 16 mCRC patients. In this study, we identified senescent and exhausted immune cells, performed enrichment analysis, cell communication, cell trajectory, and cell-based in vitro experiments to validate the results of single-cell multi-omics. This process allowed us to construct a regulatory network explaining the occurrence of LM. Finally, we utilized weighted gene co-expression network analysis (WGCNA) and 12 machine learning algorithms to create prognostic risk model.

RESULTS

We identified senescent-like myeloid cells (SMCs) and exhausted T cells (TEXs) as the primary senescent and exhausted immune cells. Our findings indicate that SMCs and TEXs can potentially activate transcription factors downstream via ANGPTL4-SDC1/SDC4, this activation plays a role in regulating the epithelial-mesenchymal transition (EMT) program and facilitates the development of LM, the results of cell-based in vitro experiments have provided confirmation of this conclusion. We also developed and validated a prognostic risk model composed of 12 machine learning algorithms.

CONCLUSION

This study elucidates the potential molecular mechanisms underlying the occurrence of LM from various angles through single-cell multi-omics analysis in CRC. It also constructs a network illustrating the role of senescent or exhausted immune cells in regulating EMT.

A versatile engineered extracellular vesicle platform simultaneously targeting and eliminating senescent stromal cells and tumor cells to promote tumor regression

Chemotherapy is an important therapeutic approach for malignant tumors for it triggers apoptosis of cancer cells. However, chemotherapy also induces senescence of stromal cells in the tumor microenvironment to promote tumor progression. Strategies aimed at killing tumor cells while simultaneously eliminating senescent stromal cells represent an effective approach to cancer treatment. Here, we developed an engineered Src-siRNA delivery system based on small extracellular vesicles (sEVs) to simultaneously eliminate senescent stromal cells and tumor cells for cancer therapy. The DSPE-PEG-modified urokinase plasminogen activator (uPA) peptide was anchored to the membranes of induced mesenchymal stem cell-derived sEVs (uPA-sEVs), and Src siRNA was loaded into the uPA-sEVs by electroporation (uPA-sEVs-siSrc). The engineered uPA-sEVs-siSrc retained the basic sEVs properties and protected against siSrc degradation. uPA peptide modification enhanced the sEVs with the ability to simultaneously target doxorubicin-induced senescent stromal cells and tumor cells. Src silencing by uPA-sEVs-siSrc induced apoptosis of both senescent stromal cells and tumor cells. The uPA-sEVs-siSrc displayed preferential tumor accumulation and effectively inhibited tumor growth in a tumor xenograft model. Furthermore, uPA-sEVs-siSrc in combination with doxorubicin significantly reduced the senescence burden and enhanced the therapeutic efficacy of chemotherapy. Taken together, uPA-sEVs-siSrc may serve as a promising therapy to kill two birds with one stone, not only killing tumor cells to achieve remarkable antitumor effect, but also eliminating senescent cells to enhance the efficacy of chemotherapeutic agent in tumor regression.

Role of Epiregulin in Lung Tumorigenesis and Therapeutic Resistance

Epidermal growth factor (EGF) signaling regulates multiple cellular processes and plays an essential role in tumorigenesis. Epiregulin (EREG), a member of the EGF family, binds to the epidermal growth factor receptor (EGFR) and ErbB4, and it stimulates EGFR-related downstream pathways. Increasing evidence indicates that both the aberrant expression and oncogenic function of EREG play pivotal roles in tumor development in many human cancers, including non-small cell lung cancer (NSCLC). EREG overexpression is induced by activating mutations in the EGFR, KRAS, and BRAF and contributes to the aggressive phenotypes of NSCLC with oncogenic drivers. Recent studies have elucidated the roles of EREG in a tumor microenvironment, including the epithelial-mesenchymal transition, angiogenesis, immune evasion, and resistance to anticancer therapy. In this review, we summarized the current understanding of EREG as an oncogene and discussed its oncogenic role in lung tumorigenesis and therapeutic resistance.

Integrative bioinformatics approaches to establish potential prognostic immune-related genes signature and drugs in the non-small cell lung cancer microenvironment

Introduction: Research has revealed that the tumor microenvironment (TME) is associated with the progression of malignancy. The combination of meaningful prognostic biomarkers related to the TME is expected to be a reliable direction for improving the diagnosis and treatment of non-small cell lung cancer (NSCLC).

Method and Result: Therefore, to better understand the connection between the TME and survival outcomes of NSCLC, we used the “DESeq2” R package to mine the differentially expressed genes (DEGs) of two groups of NSCLC samples according to the optimal cutoff value of the immune score through the ESTIMATE algorithm. A total of 978 up-DEGs and 828 down-DEGs were eventually identified. A fifteen-gene prognostic signature was established via LASSO and Cox regression analysis and further divided the patients into two risk sets. The survival outcome of high-risk patients was significantly worse than that of low-risk patients in both the TCGA and two external validation sets (p-value &lt; 0.05). The gene signature showed high predictive accuracy in TCGA (1-year area under the time-dependent ROC curve (AUC) = 0.722, 2-year AUC = 0.708, 3-year AUC = 0.686). The nomogram comprised of the risk score and related clinicopathological information was constructed, and calibration plots and ROC curves were applied, KEGG and GSEA analyses showed that the epithelial-mesenchymal transition (EMT) pathway, E2F target pathway and immune-associated pathway were mainly involved in the high-risk group. Further somatic mutation and immune analyses were conducted to compare the differences between the two groups. Drug sensitivity provides a potential treatment basis for clinical treatment. Finally, EREG and ADH1C were selected as the key prognostic genes of the two overlapping results from PPI and multiple Cox analyses. They were verified by comparing the mRNA expression in cell lines and protein expression in the HPA database, and clinical validation further confirmed the effectiveness of key genes.

Conclusion: In conclusion, we obtained an immune-related fifteen-gene prognostic signature and potential mechanism and sensitive drugs underling the prognosis model, which may provide accurate prognosis prediction and available strategies for NSCLC.

Senescent Stromal Cells in the Tumor Microenvironment: Victims or Accomplices?

Cellular senescence is a unique cellular state. Senescent cells enter a non-proliferative phase, and the cell cycle is arrested. However, senescence is essentially an active cellular phenotype, with senescent cells affecting themselves and neighboring cells via autocrine and paracrine patterns. A growing body of research suggests that the dysregulation of senescent stromal cells in the microenvironment is tightly associated with the development of a variety of complex cancers. The role of senescent stromal cells in impacting the cancer cell and tumor microenvironment has also attracted the attention of researchers. In this review, we summarize the generation of senescent stromal cells in the tumor microenvironment and their specific biological functions. By concluding the signaling pathways and regulatory mechanisms by which senescent stromal cells promote tumor progression, distant metastasis, immune infiltration, and therapy resistance, this paper suggests that senescent stromal cells may serve as potential targets for drug therapy, thus providing new clues for future related research.

The E3 ubiquitin ligases regulate PD-1/PD-L1 protein levels in tumor microenvironment to improve immunotherapy

The tumor microenvironment (TME) is the tumor surrounding environment, which is critical for tumor development and progression. TME is also involved in clinical intervention and treatment outcomes. Modulation of TME is useful for improving therapy strategies. PD-L1 protein on tumor cells interacts with PD-1 protein on T cells, contributing to T cell dysfunction and exhaustion, blockage of the immune response. Evidence has demonstrated that the expression of PD-1/PD-L1 is associated with clinical response to anti-PD-1/PD-L1 therapy in cancer patients. It is important to discuss the regulatory machinery how PD-1/PD-L1 protein is finely regulated in tumor cells. In recent years, studies have demonstrated that PD-1/PD-L1 expression was governed by various E3 ubiquitin ligases in TME, contributing to resistance of anti-PD-1/PD-L1 therapy in human cancers. In this review, we will discuss the role and molecular mechanisms of E3 ligases-mediated regulation of PD-1 and PD-L1 in TME. Moreover, we will describe how E3 ligases-involved PD-1/PD-L1 regulation alters anti-PD-1/PD-L1 efficacy. Altogether, targeting E3 ubiquitin ligases to control the PD-1/PD-L1 protein levels could be a potential strategy to potentiate immunotherapeutic effects in cancer patients.

Therapy-Induced Tumor Cell Senescence: Mechanisms and Circumvention

Plasticity of tumor cells (multitude of molecular regulation pathways) allows them to evade cytocidal effects of chemo- and/or radiation therapy. Metabolic adaptation of the surviving cells is based on transcriptional reprogramming. Similarly to the process of natural cell aging, specific features of the survived tumor cells comprise the therapy-induced senescence phenotype. Tumor cells with this phenotype differ from the parental cells since they become less responsive to drugs and form aggressive progeny. Importance of the problem is explained by the general biological significance of transcriptional reprogramming as a mechanism of adaptation to stress, and by the emerging potential of its pharmacological targeting. In this review we analyze the mechanisms of regulation of the therapy-induced tumor cell senescence, as well as new drug combinations aimed to prevent this clinically unfavorable phenomenon.