Serum taurine affects lung cancer progression by regulating tumor immune escape mediated by the immune microenvironment.

INTRODUCTION: Taurine is a naturally occurring sulfonic acid involved in various physiological and pathological processes, such as the regulation of calcium signaling, immune function, inflammatory response, and cellular aging. It has the potential to predict tumor malignant transformation and formation. Our previous work discovered the elevated taurine in lung cancer patients. However, the precise impact and mechanism of elevated serum taurine levels on lung cancer progression and the suitability of taurine or taurine-containing drinks for lung cancer patients remain unclear. OBJECTIVES: Our study aimed to systematically investigate the role of taurine in lung cancer, with the ultimate goal of contributing novel strategies for lung cancer treatment. METHODS: Lung cancer C57 and nude mice models, RNA sequencing, and stable transfection were applied to explored the effects and mechanisms of taurine on lung cancer. Tissues of 129 non-small cell lung cancer (NSCLC) patients derived from 2014 to 2017 for immunohistochemistry were collected in Taihe Hospital. RESULTS: Low doses of taurine, as well as taurine-infused beverages at equivalent doses, significantly enhanced lung tumor growth. Equally intriguing is that the promoting effect of taurine on lung cancer progression wanes as the dosage increases. The Nuclear factor erythroid 2-like 1 (Nfe2l1 or Nrf1)-reactive oxygen species (ROS)-PD-1 axis may be a potential mechanism for dual role of taurine in lung cancer progression. However, taurine's impacts on lung cancer progression and the anti-tumor function of Nfe2l1 were mainly determined by the immune competence. Taurine inhitited lung tumor growth probably by inhibiting NF-κB-mediated inflammatory responses in nude mice rather than by affecting Nfe2l1 function. As patients age increased, Nfe2l1 gene and protein gradually returned to the levels observed in healthy individuals, but lost its anti-lung cancer effects. CONCLUSIONS: Taurine emerges as a potential biomarker for lung cancer progression, predicting poor prognosis and unsuitability for specific patients. Lung cancer patients, especially young patients, should be conscious of potential effects of taurine-containing drinks. Conversely, taurine or its drinks may be more suitable for older or immune-deficient patients.

CERS4 predicts positive anti-PD-1 response and promotes immunomodulation through Rhob-mediated suppression of CD8+Tim3+ exhausted T cells in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is one of the main malignant tumors with high mortality and short survival time. Immunotherapy has become the standard treatment for advanced NSCLC, but it has the problems of drug resistance and low response rate. Therefore, obtaining effective biomarkers to predict and enhance immune checkpoint inhibitors (ICIs) efficacy in NSCLC is important. Sphingolipid metabolism is recently found to be closely involved in tumor immunotherapy. CERS4, an important sphingolipid metabolizing enzyme, is positively correlated with the efficacy of anti-PD-1 therapy for NSCLC. Upregulation of CERS4 expression could improve the efficacy of anti-PD-1 therapy for NSCLC. High expression of CERS4 could downregulate the expression of Rhob in tumor. Significantly, the ratio of CD4+/CD8+ T cell increased and the ratio of Tim-3+/CD8+ T cell decreased in spleen and peripheral blood cells. When Rhob was knocked out, the efficacy of PD-1 mAb treatment increased, and the frequency of Tim-3+ CD8+ T cell decreased. This finding further confirmed the role of sphingolipid metabolites in regulating the immunotherapeutic function of NSCLC. These metabolites may improve the efficacy of PD-1 mAb in NSCLC by regulating the CERS4/Rhob/Tim-3 axis. Overall, this study provided a potential and effective target for predicting and improving the efficacy of ICIs for NSCLC. It also provided a new perspective for the study on the mechanisms of ICIs resistance for NSCLC.

The key role of sphingolipid metabolism in cancer: New therapeutic targets, diagnostic and prognostic values, and anti-tumor immunotherapy resistance.

Biologically active sphingolipids are closely related to the growth, differentiation, aging, and apoptosis of cancer cells. Some sphingolipids, such as ceramides, are favorable metabolites in the sphingolipid metabolic pathway, usually mediating antiproliferative responses, through inhibiting cancer cell growth and migration, as well as inducing autophagy and apoptosis. However, other sphingolipids, such as S1P, play the opposite role, which induces cancer cell transformation, migration and growth and promotes drug resistance. There are also other sphingolipids, as well as enzymes, played potentially critical roles in cancer physiology and therapeutics. This review aimed to explore the important roles of sphingolipid metabolism in cancer. In this article, we summarized the role and value of sphingolipid metabolism in cancer, including the distribution of sphingolipids, the functions, and their relevance to cancer diagnosis and prognosis. We also summarized the known and potential antitumor targets present in sphingolipid metabolism, analyzed the correlation between sphingolipid metabolism and tumor immunity, and summarize the antitumor effects of natural compounds based on sphingolipids. Through the analysis and summary of sphingolipid antitumor therapeutic targets and immune correlation, we aim to provide ideas for the development of new antitumor drugs, exploration of new therapeutic means for tumors, and study of immunotherapy resistance mechanisms.

Andrographolide suppresses non-small-cell lung cancer progression through induction of autophagy and antitumor immune response.

Despite recent advances in diagnosis and therapeutic strategies, treatment of non-small-cell lung cancer (NSCLC) remains unsatisfactory in terms of prognosis. Andrographolide (AD), a principal active component of Andrographis paniculata (Burm.f.) Nees, exerts anti-cancer therapeutic properties. AD has been used for centuries in China for clinical treatment of viral infections. However, the pharmacological biology of AD in NSCLC remains unknown. In this study, AD regulated autophagy and PD-L1 expression in NSCLC. Molecular dynamics simulations indicated that AD bound directly to signal transducer and activator of transcription-3 (STAT3) with high affinity. Proteomics analysis indicated that AD reduced the expression of tumour PD-L1 in NSCLC by suppressing JAK2/STAT3 signalling. AD modulated the P62-dependent selective autophagic degradation of PD-L1 by inhibiting STAT3 phosphorylation. In vivo study revealed that AD suppressed tumour growth in H1975 xenograft mice and Lewis lung carcinoma cell models, and better efficacy was obtained at higher concentrations. AD prolonged the survival time of the mice and enhanced the treatment efficacy of anti-PD-1 mAb immunotherapy by stimulating CD8+ T cell infiltration and function. This work elucidated the specific mechanism by which AD inhibited NSCLC. Treatment with the combination of AD and anti-PD-1 mAb immunotherapy could be a potential strategy for patients with NSCLC.

A method establishment and comparison of in vivo lung cancer model development platforms for evaluation of tumour metabolism and pharmaceutical efficacy.

BACKGROUND: Currently, the identification of accurate biomarkers for the diagnosis of patients with early-stage lung cancer remains difficult. Fortunately, metabolomics technology can be used to improve the detection of plasma metabolic biomarkers for lung cancer. In a previous study, we successfully utilised machine learning methods to identify significant metabolic markers for early-stage lung cancer diagnosis. However, a related research platform for the investigation of tumour metabolism and drug efficacy is still lacking. HYPOTHESIS/PURPOSE: A novel methodology for the comprehensive evaluation of the internal tumour-metabolic profile and drug evaluation needs to be established. METHODS: The optimal location for tumour cell inoculation was identified in mouse chest for the non-traumatic orthotopic lung cancer mouse model. Microcomputed tomography (micro-CT) was applied to monitor lung tumour growth. Proscillaridin A (P.A) and cisplatin (CDDP) were utilised to verify the anti-lung cancer efficacy of the platform. The top five clinically valid biomarkers, including proline, L-kynurenine, spermidine, taurine and palmitoyl-L-carnitine, were selected as the evaluation indices to obtain a suitable lung cancer mouse model for clinical metabolomics research by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). RESULTS: The platform was successfully established, achieving 100% tumour development rate and 0% surgery mortality. P.A and CDDP had significant anti-lung cancer efficacy in the platform. Compared with the control group, four biomarkers in the orthotopic model and two biomarkers in the metastatic model had significantly higher abundance. Principal component analysis (PCA) showed a significant separation between the orthotopic/metastatic model and the control/subcutaneous/KRAS transgenic model. The platform was mainly involved in arginine and proline metabolism, tryptophan metabolism, and taurine and hypotaurine metabolism. CONCLUSION: This study is the first to simulate clinical metabolomics by comparing the metabolic phenotype of plasma in different lung cancer mouse models. We found that the orthotopic model was the most suitable for tumour metabolism. Furthermore, the anti-tumour drug efficacy was verified in the platform. The platform can very well match the clinical reality, providing better lung cancer diagnosis and securing more precise evidence for drug evaluation in the future.

Emodin induces apoptosis and suppresses non-small-cell lung cancer growth via downregulation of sPLA2-IIa.

BACKGROUND: Lung cancer has become the principal cause of cancer-related deaths. Emodin is a Chinese herb-derived compound extracted from the roots of Rheum officinale that exhibits numerous pharmacological characteristics. Secretory phospholipase A2-IIa (sPLA2-IIa) is overexpressed in cancers and plays an important role in cancer development. PURPOSE: This study aims to investigate the anti-tumor mechanism of emodin in non-small-cell lung cancer (NSCLC). METHODS: MTT assay was applied to detect the sensitivity of emodin to NSCLC cell line. Flow cytometry was used to examine the effect of emodin on cell cycle distribution and evaluate ROS level and apoptosis. Western blot analysis was utilised to examine the expression levels of sPLA2-IIa, PKM2, and AMPK and its downstream pathways induced by emodin. Enzyme inhibition assay was applied to investigate the inhibitory effect of emodin on sPLA2-IIa. The anticancer effect of emodin was also detected using an in vivo model. RESULTS: Emodin significantly inhibited NSCLC proliferation in vivo and in vitro and was relatively less cytotoxic to normal lung cell lines. Most importantly, emodin inhibited the proliferation of KRAS mutant cell lines by decreasing the expression of sPLA2-IIa and NF-κB pathways. Emodin also inhibited mTOR and AKT and activated the AMPK pathway. Furthermore, emodin induced apoptosis, increased the reactive oxygen species (ROS) level, and arrested the cell cycle. CONCLUSION: Emodin exhibited a novel anti-tumor mechanism of inhibiting the proliferation of KRAS mutant cell lines by decreasing the expression levels of sPLA2-IIa and NF-κB pathways. Hence, emodin can potentially serve as a therapeutic target in NSCLC.

Metabolomics and integrated network pharmacology analysis reveal Tricin as the active anti-cancer component of Weijing decoction by suppression of PRKCA and sphingolipid signaling.

Currently, conventional methods of treating non-small cell lung cancer (NSCLC) have many disadvantages. An alternative effective therapy with minimal adverse reactions is urgently needed. Weijing decoction (WJD), which is a classic ancient Chinese herbal prescription, has been used successfully to treat pulmonary system diseases containing lung cancer in the clinic. However, the key active component and target of Weijing decoction are still unexplored. Therefore, for the first time, our study aims to investigate the pharmacological treatment mechanism of Weijing decoction in treating NSCLC via an integrated model of network pharmacology, metabolomics and biological methods. Network pharmacology results conjectured that Tricin is a main bioactive component in this formula which targets PRKCA to suppress cancer cell growth. Metabolomics analysis demonstrated that sphingosine-1-phosphate, which is regulated by sphingosine kinase 1 and sphingosine kinase 2, is a differential metabolite in plasma between the WJD-treated group and the control group, participating in the sphingolipid signaling. In vitro experiments demonstrated that Tricin had vital effects on the proliferation, pro-apoptosis, migration and colony formation of Lewis lung carcinoma cells. Through a series of validation assays, Tricin inhibited the tumor growth mainly by suppressing PRKCA/SPHK/S1P signaling and antiapoptotic signaling. On the other hand, Weijing formula could inhibit the tumor growth and prolong the survival time. A high dosage of Tricin was much more potent in animal experiments. In conclusion, we confirmed that Weijing formula and its primary active compound Tricin are promising alternative treatments for NSCLC patients.