CD73, a Promising Therapeutic Target of Diclofenac, Promotes Metastasis of Pancreatic Cancer through a Nucleotidase Independent Mechanism

Integrated multiomics machine learning and mediated Mendelian randomization investigate the molecular subtypes and prognosis lung squamous cell carcinoma

Background

Lung squamous cell carcinoma (LUSC) lacks specific early diagnostic markers. Given the critical role of 5'-Nucleotidase Ecto (NT5E) in immune evasion and therapy resistance of cancer cells and the involvement of Dual Specificity Phosphatase 4 (DUSP4) in tumor cell proliferation through inhibition of the ERK signaling pathway, incorporating NT5E and DUSP4 into the consensus machine learning signature (CMLS) system in this study holds significant potential for investigating the early diagnosis and immune microenvironment of LUSC. The objective of this study was to explore the prognostic targets of LUSC.

Methods

Employing integrated algorithms enhances the ability to identify molecular subtypes and key features from multiple perspectives. A combination of 10 clustering algorithms and multi-omics data from LUSC patients, merged with 10 machine learning algorithms, was used to analyze and identify high-resolution molecular subsets and develop a CMLS. Mediated Mendelian randomization (MR) was utilized to explore mediations between immune cells and metabolites associated with CMLS.

Results

Cluster 1 demonstrated elevated infiltration of immune and stromal components, indicating an immunosuppressive microenvironment predominantly driven by tumor-associated macrophages or other inhibitory cells. In contrast, Cluster 2 displayed a metabolism-driven phenotype associated with improved prognosis. Mediated MR provided further insights into the causal relationships among CMLS, macrophages, and metabolites in LUSC. Validation of the RAS-RAF-MEK-ERK signaling pathway in conjunction with CMLS reinforced the immune characteristics of CMLS.

Conclusions

The integration of CMLS with multi-omics offers a robust framework for predicting prognosis, elucidating the causal interactions between the immune microenvironment and metabolic reprogramming in LUSC, and identifying patient subgroups likely to benefit from immunotherapy.

HACD2 Promotes Pancreatic Cancer Progression by Enhancing PKM2 Dissociation From PRKN in a Dehydratase-Independent Manner

3-Hydroxyacyl-CoA dehydratase 2 (HACD2), an obesity-related gene involved in the elongation of long-chain fatty acids, is highly expressed in pancreatic cancer (PC) and is associated with patient prognosis. Interestingly, the study reveals that HACD2 mediated the proliferation of PC cells in a dehydratase-independent manner, affecting the downstream glycolytic pathway. Mechanistically, HACD2 promotes PC cells proliferation by binding to E3 ubiquitin-protein ligase parkin (PRKN) and enhancing pyruvate kinase PKM (PKM2) dissociation from PRKN, resulting in reduced ubiquitination of PKM2 and increased dimerization of PKM2, which subsequently promote c-Myc expression and tumor growth. Moreover, HACD2 overexpression-induced PC growth is mitigated by knockdown of PKM2 or overexpression of PRKN. Furthermore, the weight loss drug orlistat, which potentially binds to HACD2, disrupted the interaction between HACD2 and PRKN and further increased the ubiquitination of PKM2. Therefore, this study elucidates the mechanism by which the obesity-related gene HACD2 regulates PC cells proliferation through a noncanonical signaling pathway, which may provide a potential new target and strategy for the individualized clinical treatment of PC.

Targeting Triple NK Cell Suppression Mechanisms: A Comprehensive Review of Biomarkers in Pancreatic Cancer Therapy

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor outcomes due to frequent recurrence, metastasis, and resistance to treatment. A major contributor to this resistance is the tumor's ability to suppress natural killer (NK) cells, which are key players in the immune system's fight against cancer. In PDAC, the tumor microenvironment (TME) creates conditions that impair NK cell function, including reduced proliferation, weakened cytotoxicity, and limited tumor infiltration. This review examines how interactions between tumor-derived factors, NK cells, and the TME contribute to tumor progression and treatment resistance. To address these challenges, we propose a new "Triple NK Cell Biomarker Approach". This strategy focuses on identifying biomarkers from three critical areas: tumor characteristics, TME factors, and NK cell suppression mechanisms. This approach could guide personalized treatments to enhance NK cell activity. Additionally, we highlight the potential of combining NK cell-based therapies with conventional treatments and repurposed drugs to improve outcomes for PDAC patients. While progress has been made, more research is needed to better understand NK cell dysfunction and develop effective therapies to overcome these barriers.

Impact of Species and Tissue Differences on In Vitro Glucuronidation of Diclofenac

BACKGROUND

The aim of this study is to determine the impact of species and tissue differences on the glucuronidation of diclofenac in vitro.

METHOD

Microsomes from different species (rat, monkey, mouse, dog, and human) and rat and human tissues (liver, intestine, and kidney) were used to assess the rate of glucuronidation reaction of diclofenac. The metabolites were quantified using ultra high-performance liquid chromatography (UHPLC) and fitted into a Michaelis-Menten model to determine the metabolic kinetic parameters.

RESULTS

The results showed higher rates of metabolism in the liver as compared to that of the intestine and kidney by both human and rat tissues microsomes. There were also differences in the rate of metabolism in the liver across the tested species, with mouse liver microsome having the highest maximum reaction rate (Vmax) at 7.22 nmol/min/mg followed by human liver microsome at 6.66 ± 0.33 nmol/min/mg, dog liver microsome at 5.05 ± 0.42 nmol/min/mg, monkey liver microsome at 3.88 ± 0.15 nmol/min/mg, and rat liver microsome at 0.83 ± 0.04 nmol/min/mg.

CONCLUSIONS

This study demonstrated that the liver is the major organ for the glucuronidation of diclofenac. In addition, glucuronidation of diclofenac was different across the tested species; therefore, the influence of species should be taken into consideration in the pharmacological, pharmaceutical, and toxicological study of diclofenac.

The Role of Adenosine in Overcoming Resistance in Sarcomas

Resistance to systemic therapies in sarcomas poses a significant challenge to improving clinical outcomes. Recent research has concentrated on the tumor microenvironment's role in sarcoma progression and treatment resistance. This microenvironment comprises a variety of cell types and signaling molecules that influence tumor behavior, including proliferation, metastasis, and resistance to therapy. Adenosine, abundant in the tumor microenvironment, has been implicated in promoting immunosuppression and chemoresistance. Targeting adenosine receptors and associated pathways offers a novel approach to enhancing immune responses against tumors, potentially improving immunotherapy outcomes in cancers, including sarcomas. Manipulating adenosine signaling also shows promise in overcoming chemotherapy resistance in these tumors. Clinical trials investigating adenosine receptor antagonists in sarcomas have fueled interest in this pathway for sarcoma treatment. Ultimately, a comprehensive understanding of the tumor and vascular microenvironments, as well as the adenosine pathway, may open new avenues for improving treatment outcomes and overcoming resistance in sarcoma. Further studies and clinical trials are crucial to validate these findings and optimize therapeutic strategies, particularly for osteosarcoma. This study provides a literature review exploring the potential role of the adenosine pathway in sarcomas.

Exploring COX-Independent Pathways: A Novel Approach for Meloxicam and Other NSAIDs in Cancer and Cardiovascular Disease Treatment

As a fundamental process of innate immunity, inflammation is associated with the pathologic process of various diseases and constitutes a prevalent risk factor for both cancer and cardiovascular disease (CVD). Studies have indicated that several non-steroidal anti-inflammatory drugs (NSAIDs), including Meloxicam, may prevent tumorigenesis, reduce the risk of carcinogenesis, improve the efficacy of anticancer therapies, and reduce the risk of CVD, in addition to controlling the body's inflammatory imbalances. Traditionally, most NSAIDs work by inhibiting cyclooxygenase (COX) activity, thereby blocking the synthesis of prostaglandins (PGs), which play a role in inflammation, cancer, and various cardiovascular conditions. However, long-term COX inhibition and reduced PGs synthesis can result in serious side effects. Recent studies have increasingly shown that some selective COX-2 inhibitors and NSAIDs, such as Meloxicam, may exert effects beyond COX inhibition. This emerging understanding prompts a re-evaluation of the mechanisms by which NSAIDs operate, suggesting that their benefits in cancer and CVD treatment may not solely depend on COX targeting. In this review, we will explore the potential COX-independent mechanisms of Meloxicam and other NSAIDs in addressing oncology and cardiovascular health.

CD73 promotes non-small cell lung cancer metastasis by regulating Axl signaling independent of GAS6

As catabolic enzyme, CD73 dephosphorylates adenosine monophosphate (AMP) and can also regulate tumor cell proliferation and metastasis. To date, very few studies have explored the role of CD73 in mediating non-small cell lung cancer (NSCLC) metastasis, and the underlying transducing signal has not been elucidated. In the present study, we demonstrated that the CD73/Axl axis could regulate Smad3-induced epithelial-to-mesenchymal transition (EMT) to promote NSCLC metastasis. Mechanically, CD73 can be secreted via the Golgi apparatus transport pathway. Then secreted CD73 may activate AXl by directly bind with site R55 located in Axl extracellular domain independently of GAS6. In addition, we proved that CD73 can stabilize Axl expression via inhibiting CBLB expression. We also identified the distinct function of CD73 activity in adenocarcinoma and squamous cell carcinoma. Our findings indicated a role of CD73 in mediating NSCLC metastasis and propose it as a therapeutic target for NSCLC.

Regulation of CD73 on NAD metabolism: Unravelling the interplay between tumour immunity and tumour metabolism

CD73, a cell surface-bound nucleotidase, serves as a crucial metabolic and immune checkpoint. Several studies have shown that CD73 is widely expressed on immune cells and plays a critical role in immune escape, cell adhesion and migration as a costimulatory molecule for T cells and a factor in adenosine production. However, recent studies have revealed that the protumour effects of CD73 are not limited to merely inhibiting the antitumour immune response. Nicotinamide adenine dinucleotide (NAD+) is a vital bioactive molecule in organisms that plays essential regulatory roles in diverse biological processes within tumours. Accumulating evidence has demonstrated that CD73 is involved in the transport and metabolism of NAD, thereby regulating tumour biological processes to promote growth and proliferation. This review provides a holistic view of CD73-regulated NAD + metabolism as a complex network and further highlights the emerging roles of CD73 as a novel target for cancer therapies.

Comprehensive analysis of KLF family reveals KLF6 as a promising prognostic and immune biomarker in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest tumors worldwide, with extremely aggressive and complicated biology. Krüppel-like factors (KLFs) encode a series of transcriptional regulatory proteins and play crucial roles in a variety of processes, including tumor cell differentiation and proliferation. However, the potential biological functions and possible pathways of KLFs in the progression of PDAC remain elusive.

METHODS

We systematically evaluated the transcriptional variations and expression patterns of KLFs in pancreatic cancer from the UCSC Xena. Based on difference analysis, the non-negative matrix factorization (NMF) algorithm was utilized to identify the immune characteristics and clinical significance of two different subtypes. The multivariate Cox regression was used to construct the risk model and then explore the differences in tumor immune microenvironment (TIME) and drug sensitivity between high and low groups. Through single-cell RNA sequencing (scRNA-seq) analysis, we screened KLF6 and further investigated its biological functions in pancreatic cancer and pan-cancer.

RESULTS

The KLFs exhibited differential expression and mutations in the transcriptomic profile of PDAC. According to the expression of KLFs, patients were classified into two distinct subtypes, each exhibiting significant differences in prognosis and TIME. Moreover, the KLF signature was developed using univariate Cox and Lasso regression, which proved to be a reliable and effective prognostic model. Furthermore, the KLF_Score was closely associated with immune infiltration, response to immunotherapy, and drug sensitivity and we screened small molecule compounds targeting prognostic genes separately. Through scRNA-seq analysis, KLF6 was selected to further demonstrate its role in the malignance of PC in vitro. Finally, pan-cancer analysis emphasized the biological significance of KLF6 in multiple types of tumors and its clinical utility in assessing cancer prognosis.

CONCLUSION

This study elucidated the pivotal role of KLF family genes in the malignant development of PC through comprehensive analysis and revealed that KLF6 would be a novel diagnostic biomolecule marker and potential therapeutic target for PDAC.

Ubiquitin signaling in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignant tumor of the digestive system, characterized by rapid progression and being prone to metastasis. Few effective treatment options are available for PDAC, and its 5-year survival rate is less than 9%. Many cell biological and signaling events are involved in the development of PDAC, among which protein post-translational modifications (PTMs), such as ubiquitination, play crucial roles. Catalyzed mostly by a three-enzyme cascade, ubiquitination induces changes in protein activity mainly by altering their stability in PDAC. Due to their role in substrate recognition, E3 ubiquitin ligases (E3s) dictate the outcome of the modification. Ubiquitination can be reversed by deubiquitylases (DUBs), which, in return, modified proteins to their native form. Dysregulation of E3s or DUBs that disrupt protein homeostasis is involved in PDAC. Moreover, the ubiquitination system has been exploited to develop therapeutic strategies, such as proteolysis-targeting chimeras (PROTACs). In this review, we summarize recent progress in our understanding of the role of ubiquitination in the development of PDAC and offer perspectives in the design of new therapies against this highly challenging disease.

Tumor Microenvironment Responsive CD8+ T Cells and Myeloid-Derived Suppressor Cells to Trigger CD73 Inhibitor AB680-Based Synergistic Therapy for Pancreatic Cancer

CD73 plays a critical role in the pathogenesis and immune escape in pancreatic ductal adenocarcinoma (PDAC). AB680, an exceptionally potent and selective inhibitor of CD73, is administered in an early clinical trial, in conjunction with gemcitabine and anti-PD-1 therapy, for the treatment of PDAC. Nevertheless, the specific therapeutic efficacy and immunoregulation within the microenvironment of AB680 monotherapy in PDAC have yet to be fully elucidated. In this study, AB680 exhibits a significant effect in augmenting the infiltration of responsive CD8+ T cells and prolongs the survival in both subcutaneous and orthotopic murine PDAC models. In parallel, it also facilitates chemotaxis of myeloid-derived suppressor cells (MDSCs) by tumor-derived CXCL5 in an AMP-dependent manner, which may potentially contribute to enhanced immunosuppression. The concurrent administration of AB680 and PD-1 blockade, rather than gemcitabine, synergistically restrain tumor growth. Notably, gemcitabine weakened the efficacy of AB680, which is dependent on CD8+ T cells. Finally, the supplementation of a CXCR2 inhibitor is validated to further enhance the therapeutic efficacy when combined with AB680 plus PD-1 inhibitor. These findings systematically demonstrate the efficacy and immunoregulatory mechanism of AB680, providing a novel, efficient, and promising immunotherapeutic combination strategy for PDAC.

Integrated single-cell and bulk RNA sequencing in pancreatic cancer identifies disulfidptosis-associated molecular subtypes and prognostic signature

Pancreatic cancer (PC) is known for its high degree of heterogeneity and exceptionally adverse outcome. While disulfidptosis is the most recently identified form of cell death, the predictive and therapeutic value of disulfidptosis-related genes (DRGs) for PC remains unknown. RNA sequencing data with the follow-up information, were retrieved from the TCGA and ICGC databases. Consensus clustering analysis was conducted on patient data using R software. Subsequently, the LASSO regression analysis was conducted to create a prognostic signature for foreseeing the outcome of PC. Differences in relevant pathways, mutational landscape, and tumor immune microenvironment were compared between PC samples with different risk levels. Finally, we experimentally confirmed the impact of DSG3 on the invasion and migration abilities of PC cells. All twenty DRGs were found to be hyperexpressed in PC tissues, and fourteen of them significantly associated with PC survival. Using consensus clustering analysis based on these DRGs, four DRclusters were identified. Additionally, altogether 223 differential genes were evaluated between clusters, indicating potential biological differences between them. Four gene clusters (geneClusters) were recognized according to these genes, and a 10-gene prognostic signature was created. High-risk patients were found to be primarily enriched in signaling pathways related to the cell cycle and p53. Furthermore, the rate of mutations was markedly higher in high-risk patients, besides important variations were present in terms of immune microenvironment and chemotherapy sensitivity among patients with different risk levels. DSG3 could appreciably enhance the invasion and migration of PC cells. This work, based on disulfidoptosis-related genes (DRGs), holds the promise of classifying PC patients and predicting their prognosis, mutational landscape, immune microenvironment, and drug therapy. These insights could boost an improvement in a better comprehension of the role of DRGs in PC as well as provide new opportunities for prognostic prediction and more effective treatment strategies.

Lansoprazole Increases Inorganic Pyrophosphate in Patients with Pseudoxanthoma Elasticum: A Double-Blind, Randomized, Placebo-Controlled Crossover Trial

Pseudoxanthoma elasticum (PXE) is characterized by low levels of inorganic pyrophosphate (PPi) and a high activity of tissue-nonspecific alkaline phosphatase (TNAP). Lansoprazole is a partial inhibitor of TNAP. The aim was to investigate whether lansoprazole increases plasma PPi levels in subjects with PXE. We conducted a 2 × 2 randomized, double-blind, placebo-controlled crossover trial in patients with PXE. Patients were allocated 30 mg/day of lansoprazole or a placebo in two sequences of 8 weeks. The primary outcome was the differences in plasma PPi levels between the placebo and lansoprazole phases. 29 patients were included in the study. There were eight drop-outs due to the pandemic lockdown after the first visit and one due to gastric intolerance, so twenty patients completed the trial. A generalized linear mixed model was used to evaluate the effect of lansoprazole. Overall, lansoprazole increased plasma PPi levels from 0.34 ± 0.10 µM to 0.41 ± 0.16 µM (p = 0.0302), with no statistically significant changes in TNAP activity. There were no important adverse events. 30 mg/day of lansoprazole was able to significantly increase plasma PPi in patients with PXE; despite this, the study should be replicated with a large number of participants in a multicenter trial, with a clinical end point as the primary outcome.