Tumor metabolism and associated serum metabolites define prognostic subtypes of Asian hepatocellular carcinoma

Detection, mechanisms, and therapeutic implications of oncometabolites

Metabolic abnormalities are a hallmark of cancer cells and are essential to tumor progression. Oncometabolites have pleiotropic effects on cancer biology and affect a plethora of processes, from oncogenesis and metabolism to therapeutic resistance. Targeting oncometabolites, therefore, could offer promising therapeutic avenues against tumor growth and resistance to treatments. Recent advances in characterizing the metabolic profiles of cancer cells are shedding light on the underlying mechanisms and associated metabolic networks. This review summarizes the diverse detection methods, molecular mechanisms, and therapeutic targets of oncometabolites, which may lead to targeting oncometabolism for cancer therapy.

Water extract of Pingchuan formula ameliorated murine asthma through modulating metabolites and gut microbiota

BACKGROUND

Pingchuan formula is a traditional Chinese herbal prescription for asthma, but its components and underlying mechanisms remain unclear. Here, we evaluated its anti-asthmatic actvity and regulatory effects on the gut microbiota in mice based on the traditional Chinese medicine Zang-Fu theory, which proposed the exterior-interior relationship between the lung and the large intestine.

METHODS

Mouse model withovalbumin (OVA)-induced asthma was used to assess the protective effect of the water extract of Pingchuan formula (PC). The chemical compounds of PC and mouse serum metabolites were identified by Ultraperformance liquid chromatography-Q Exactive HF-X spectrometry. Gut microbiota was evaluated by 16 S rRNA gene sequencing. The gut microbiota was depleted with a broad-spectrum antibiotic mixture (Abx) to explore whether it plays a role in the protective effects of PC.

RESULTS

PC mainly contains phenols, flavonoids, alkaloids, carboxylic acids, and their derivatives. PC attenuated OVA-induced asthma in mice by alleviating inflammatory infiltration, indicated by decreased levels of IL-18, IL-6, IL-4, and Eotaxin in lung tissues. PC treatment altered the serum metabolites and affected the pyrimidine pathway. In addition, our results showed that acacetin and abscisic acid were the key serum metabolites PC treatment changed the composition of gut microbiota by increasing the relative abundance of Clostridia_UCG_014 and Akkermansia while decreasing Blautia, Barnesiella, and Clostridium_Ⅲ at the genus level. Importantly, the Abx treatment partly abolished the anti-asthmatic effect of PC.

CONCLUSION

We demonstrated that PC could alleviate OVA-induced asthma in mice and protect against inflammatory infiltration in lungs via modulating the serum metabolites and gut microbiota, thereby providing a new reference for the therapeutic effect of PC.

Biomarkers for immunotherapy of hepatocellular carcinoma

Immune-checkpoint inhibitors (ICIs) are now widely used for the treatment of patients with advanced-stage hepatocellular carcinoma (HCC). Two different ICI-containing regimens, atezolizumab plus bevacizumab and tremelimumab plus durvalumab, are now approved standard-of-care first-line therapies in this setting. However, and despite substantial improvements in survival outcomes relative to sorafenib, most patients with advanced-stage HCC do not derive durable benefit from these regimens. Advances in genome sequencing including the use of single-cell RNA sequencing (both of tumour material and blood samples), as well as immune cell identification strategies and other techniques such as radiomics and analysis of the microbiota, have created considerable potential for the identification of novel predictive biomarkers enabling the accurate selection of patients who are most likely to derive benefit from ICIs. In this Review, we summarize data on the immunology of HCC and the outcomes in patients receiving ICIs for the treatment of this disease. We then provide an overview of current biomarker use and developments in the past 5 years, including gene signatures, circulating tumour cells, high-dimensional flow cytometry, single-cell RNA sequencing as well as approaches involving the microbiome, radiomics and clinical markers. Novel concepts for further biomarker development in HCC are then discussed including biomarker-driven trials, spatial transcriptomics and integrated 'big data' analysis approaches. These concepts all have the potential to better identify patients who are most likely to benefit from ICIs and to promote the development of new treatment approaches.

Gut dysbiosis in Thai intrahepatic cholangiocarcinoma and hepatocellular carcinoma

Primary liver cancer (PLC), which includes intrahepatic cholangiocarcinoma (iCCA) and hepatocellular carcinoma (HCC), has the highest incidence of all cancer types in Thailand. Known etiological factors, such as viral hepatitis and chronic liver disease do not fully account for the country's unusually high incidence. However, the gut-liver axis, which contributes to carcinogenesis and disease progression, is influenced by the gut microbiome. To investigate this relationship, fecal matter from 44 Thai PLC patients and 76 healthy controls were subjected to whole-genome metagenomic shotgun sequencing and then analyzed by marker gene-based and assembly based methods. Results revealed greater gut microbiome heterogeneity in iCCA compared to HCC and healthy controls. Two Veillonella species were found to be more abundant in iCCA samples and could distinguish iCCA from HCC and healthy controls. Conversely, Ruminococcus gnavus was depleted in iCCA patients and could distinguish HCC from iCCA samples. High Veillonella genus counts in the iCCA group were associated with enriched amino acid biosynthesis and glycolysis pathways, while enriched phospholipid and thiamine metabolism pathways characterized the HCC group with high Blautia genus counts. These findings reveal distinct landscapes of gut dysbiosis among Thai iCCA and HCC patients and warrant further investigation as potential biomarkers.

Dynamic microbiome and metabolome analyses reveal the interaction between gut microbiota and anti-PD-1 based immunotherapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a severe disease with high mortality and global incidence. However, the interaction between the gut microbiome and combined immunotherapy for HCC is yet unclear. In this prospective clinical study, patients with unresectable HCC who had not received systemic treatment previously were recruited. Fecal and serum samples were collected at the baseline point and before each subsequent administration as specified. Between October 20, 2019 and February 2, 2021, 61 patients were screened for eligibility, of whom 35 patients were finally included in this study. Alpha diversity of fecal samples from patients who responded to immunotherapy was higher than that of non-responders at baseline. However, the prominent alpha-diversity between responders and non-responders became similar as early as week 6 after treatment. The beta diversity of inter-group did not show significant difference at the 9th week after treatment. Alpha-D-Glucose was the only serum metabolite that differed between the responders and non-responders after 3 months. Responder-enriched Ruminococcus showed a positive correlation with serum galactaric acid, while Klebsiella was positively associated with 3-methylindole and lenticin (all P<0.01). The machine learning classifier based on serum metabolites were more able to discriminate HCC patients who potentially benefited from immunotherapy at baseline (AUC 0.793, 95% CI: 0.632-0.954) than the classifier of gut microbiome. In conclusion, gut microbiome biomarkers are associated with the response to anti-PD-1 based immunotherapy in HCC patients. Classifiers based on gut microbiota and serum metabolites are feasible. This article is protected by copyright. All rights reserved.

The gut-liver axis: host microbiota interactions shape hepatocarcinogenesis

Although their etiologies vary, tumors share a common trait: the control of an oncogenic transcriptional program that is regulated by the interaction of the malignant cells with the stromal and immune cells in the tumor microenvironment (TME). The TME shows high phenotypic and functional heterogeneity that may be modulated by interactions with commensal microbes (the microbiota) both systemically and locally. Unlike host cells, the microbiota adapts after environmental perturbations, impacting host-microbe interactions. In the liver, the bidirectional relationship in the gut and its associated microbiota creates an interdependent environment. Therefore, the gut microbiota and its metabolites modulate liver gene expression directly and indirectly, causing an imbalance in the gut-liver axis, which may result in disease, including carcinogenesis.