Exosomes contain proteins, lipids, and biological molecules such as DNA and RNA. Nucleic acids in exosomes are a group of molecules that can act as biomarkers. Currently, there are many reports on ...exosomal microRNAs, which are ideal biomarkers for the early diagnosis of cancer. However, there are few reports on the role of exosomal microRNAs in the diagnosis and prognosis of hepatocellular carcinoma (HCC).
To understand the mechanism of exosomal microRNA-224 (miR-224) in the development of HCC and evaluate its diagnostic and prognostic value.
Cell culture and transfection of exosomal miRNA-224, real-time quantitative PCR, luciferase reporter assay, and other methods were used to find new biomarkers related to the development of HCC that can be used to diagnose HCC and predict HCC prognosis.
By targeting glycine N-methyltransferase, incubating exosomes with miR-224 mimic resulted in a significant increase in cell proliferation compared to that of the control group, while incubation with the miR-224 inhibitor significantly reduced cell proliferation. The same results were obtained for the cell invasion assay. Serum exosomal miR-224 did have some ability to differentiate patients with HCC from healthy controls, with an area under the curve of 0.910, and HCC patients with higher serum exosomal miR-224 expression had lower overall survival.
Exosomal miR-224 is a tumor promotor and can be a marker of diagnosis and prognosis of HCC patients, however, its ability to distinguish liver diseases needs further verification.
Background & Aims Phosphatidylinositide 3-kinase (PI3K) is deregulated in many human tumor types, including primary liver malignancies. The kinase v-akt murine thymoma viral oncogene homolog 1 (Akt) ...and mammalian target of rapamycin complex (mTORC1) are effectors of PI3K that promote cell growth and survival, but their individual roles in tumorigenesis are not well defined. Methods In livers of albumin ( Alb ) -Cre mice, we selectively deleted tuberous sclerosis ( Tsc ) 1 , a negative regulator of Ras homolog enriched in brain and mTORC1, along with Phosphatase and tensin homolog ( Pten ), a negative regulator of PI3K. Tumor tissues were characterized by histologic and biochemical analyses. Results The Tsc1fl/fl;AlbCre , Ptenfl/fl;AlbCre , and Tsc1fl/fl;Ptenfl/fl;AlbCre mice developed liver tumors that differed in size, number, and histologic features. Livers of Tsc1fl/fl;AlbCre mice did not develop steatosis; tumors arose later than in the other strains of mice and were predominantly hepatocellular carcinomas. Livers of the Ptenfl/fl;AlbCre mice developed steatosis and most of the tumors that formed were intrahepatic cholangiocarcinomas. Livers of Tsc1fl/fl;Ptenfl/fl;AlbCre formed large numbers of tumors, of mixed histologies, with the earliest onset of any strain, indicating that loss of Tsc1 and Pten have synergistic effects on tumorigenesis. In these mice, the combination of rapamycin and MK2206 was more effective in reducing liver cell proliferation and inducing cell death than either reagent alone. Tumor differentiation correlated with Akt and mTORC1 activities; the ratio of Akt:mTORC1 activity was high throughout the course of intrahepatic cholangiocarcinomas development and low during hepatocellular carcinoma development. Compared with surrounding nontumor liver tissue, tumors from all 3 strains had increased activities of Akt, mTORC1, and mitogen-activated protein kinase and overexpressed fibroblast growth factor receptor 1. Inhibition of fibroblast growth factor receptor 1 in Tsc1-null mice suppressed Akt and mitogen-activated protein kinase activities in tumor cells. Conclusions Based on analyses of knockout mice, mTORC1 and Akt have different yet synergistic effects during the development of liver tumors in mice.
The tyrosine kinase inhibitor lenvatinib is a first-line drug for treating patients with advanced hepatocellular carcinoma (HCC). However, its efficacy is severely hampered by drug resistance. ...Insights into the molecular mechanisms underlying lenvatinib resistance could provide new strategies to improve and prolong responses. Here, we performed unbiased proteomic screening of parental and lenvatinib-resistant HCC cells and discovered that methyltransferase-like protein-1 (METTL1) and WD repeat domain 4 protein (WDR4), the two key components of the tRNA N7-methylguanosine (m7G) methyltransferase complex, were dramatically upregulated in lenvatinib-resistant cells. METTL1 knockdown overrode resistance by impairing the proliferation capacity of HCC cells and promoting apoptosis under lenvatinib treatment. In addition, overexpression of wild-type METTL1 but not its catalytic dead mutant induced lenvatinib resistance. Animal experiments including hydrodynamic injection, subcutaneous implantation, and orthotopic xenograft mouse models further demonstrated the critical function of METTL1/WDR4-mediated m7G tRNA modification in promoting lenvatinib resistance in vivo. Mechanistically, METTL1 promoted translation of EGFR pathway genes to trigger drug resistance. This work reveals the important role of METTL1-mediated m7G tRNA modification in promoting lenvatinib resistance and provides a promising prediction marker and intervention target for resistance.
Upregulation of tRNA m7G methyltransferase complex components METTL1 and WDR4 promotes lenvatinib resistance in HCC and confers a sensitivity to METTL1 targeting, providing a promising strategy to override resistance.
Ferroptosis, a form of iron-dependent cell death driven by cellular metabolism and iron-dependent lipid peroxidation, has been implicated as a tumor-suppressor function for cancer therapy. Recent ...advance revealed that the sensitivity to ferroptosis is tightly linked to numerous biological processes, including metabolism of amino acid and the biosynthesis of glutathione. Here, by using a high-throughput CRISPR/Cas9-based genetic screen in HepG2 hepatocellular carcinoma cells to search for metabolic proteins inhibiting ferroptosis, we identified a branched-chain amino acid aminotransferase 2 (BCAT2) as a novel suppressor of ferroptosis. Mechanistically, ferroptosis inducers (erastin, sorafenib, and sulfasalazine) activated AMPK/SREBP1 signaling pathway through iron-dependent ferritinophagy, which in turn inhibited BCAT2 transcription. We further confirmed that BCAT2 as the key enzyme mediating the metabolism of sulfur amino acid, regulated intracellular glutamate level, whose activation by ectopic expression specifically antagonize system Xc
inhibition and protected liver and pancreatic cancer cells from ferroptosis in vitro and in vivo. On the contrary, direct inhibition of BCAT2 by RNA interference, or indirect inhibition by blocking system Xc
activity, triggers ferroptosis. Finally, our results demonstrate the synergistic effect of sorafenib and sulfasalazine in downregulating BCAT2 expression and dictating ferroptotic death, where BCAT2 can also be used to predict the responsiveness of cancer cells to ferroptosis-inducing therapies. Collectively, these findings identify a novel role of BCAT2 in ferroptosis, suggesting a potential therapeutic strategy for overcoming sorafenib resistance.
Previous clinical studies have found that the levels of tumor-infiltrating lymphocytes (TILs) significantly correlated with prognosis in hepatocellular carcinoma (HCC). However, these conclusions and ...data remain controversial. We performed a systematic review and meta-analysis to assess the prognostic value and clinical utilization of TILs in patients with HCC. A total of 23 relevant studies of 3173 patients were included into our meta-analysis. The results demonstrated that high levels of CD8
and CD3
TILs had a better prognostic value on overall survival (OS), with HRs of 0.71 (P = 0.04) and 0.63 (P = 0.03), respectively, compared to low levels, as did high levels of CD8
, CD3
and CD4
TILs on disease/recurrence-free survival (DFS/RFS), with HRs of 0.66 (P = 0.01), 0.60 (P = 0.01) and 0.79 (P = 0.04), respectively. In contrast, high levels of FoxP3
TILs had a worse prognostic value on OS and DFS/RFS, with HRs of 2.06 (P < 0.00001) and 1.77 (P < 0.00001), respectively. The FoxP3
/CD4
and FoxP3
/CD8
ratios negatively correlated with OS and DFS/RFS. These findings suggest that TILs may serve as a prognostic biomarker in HCC. However, further research should be performed to clarify the clinical value of TILs in HCC.
The objectives were to describe Surveillance, Epidemiology and End Results (SEER) hepatocellular carcinoma (HCC) incidence trends and the US liver cancer mortality trends by geography, age, ...race/ethnicity, and gender.
HCC incidence data from SEER 18 registries and liver cancer mortality data from the National Center for Health Statistics were analyzed. Rates and joinpoint trends were calculated by demographic subgroup. State-level liver cancer mortality rates and trends were mapped.
HCC incidence rates in SEER registries did not significantly increase during 2007-2010; however, the US liver cancer mortality rates did increase. HCC incidence and liver cancer mortality rates increased among black, Hispanic, and white men aged 50+ years and decreased among 35-49-year-old men in all racial/ethnic groups including Asians/Pacific Islanders. Significantly increasing incidence and mortality rates among women were restricted to blacks, Hispanics, and whites aged 50+ years. Asian/Pacific Islander liver cancer mortality rates decreased during 2000-2010 with decreasing rates among women aged 50-64 years and men aged 35-49 years and stable rates in other groups. During 2006-2010, among individuals 50-64 years of age, blacks and Hispanics had higher incidence and mortality rates than Asians/Pacific Islanders. Liver cancer mortality rates were highest in Louisiana, Mississippi, Texas, and Washington, DC.
Decreasing HCC incidence and liver cancer mortality rates among Asians/Pacific Islanders, men aged 35-49 years, and the nonsignificant increase in overall HCC incidence rates suggest that the peak of the epidemic may be near or have passed. Findings of geographic variation in mortality rates can inform control efforts.
Despite considerable efforts to identify cancer metabolic alterations that might unveil druggable vulnerabilities, systematic characterizations of metabolism as it relates to functional genomic ...features and associated dependencies remain uncommon. To further understand the metabolic diversity of cancer, we profiled 225 metabolites in 928 cell lines from more than 20 cancer types in the Cancer Cell Line Encyclopedia (CCLE) using liquid chromatography-mass spectrometry (LC-MS). This resource enables unbiased association analysis linking the cancer metabolome to genetic alterations, epigenetic features and gene dependencies. Additionally, by screening barcoded cell lines, we demonstrated that aberrant ASNS hypermethylation sensitizes subsets of gastric and hepatic cancers to asparaginase therapy. Finally, our analysis revealed distinct synthesis and secretion patterns of kynurenine, an immune-suppressive metabolite, in model cancer cell lines. Together, these findings and related methodology provide comprehensive resources that will help clarify the landscape of cancer metabolism.
Although circulating neutrophils are associated with distant metastasis and poor outcome in a number of epithelial malignancies, it remains unclear whether neutrophils play an active causal role in ...the metastatic cascade. Using in vivo models of metastasis, we found that neutrophils promote cancer cell adhesion within liver sinusoids and, thereby, influence metastasis. Neutrophil depletion before cancer cell inoculation resulted in a decreased number of gross metastases in an intrasplenic model of liver metastasis. This effect was reversed when inflamed neutrophils were co-inoculated with cancer cells. In addition, early adhesion within liver sinusoids was inhibited in the absence of neutrophils and partially restored with a short perfusion of isolated activated neutrophils. Intravital microscopy showed that cancer cells adhered directly on top of arrested neutrophils, indicating that neutrophils may act as a bridge to facilitate interactions between cancer cells and the liver parenchyma. The adhesion of lipopolysaccharide-activated neutrophils to cancer cells was mediated by neutrophil Mac-1/ICAM-1. Our findings, therefore, show a novel role for neutrophils in the early adhesive steps of liver metastasis.
There have been major advances in the armamentarium for hepatocellular carcinoma (HCC) since the last official update of the Barcelona Clinic Liver Cancer prognosis and treatment strategy published ...in 2018. Whilst there have been advances in all areas, we will focus on those that have led to a change in strategy and we will discuss why, despite being encouraging, data for select interventions are still too immature for them to be incorporated into an evidence-based model for clinicians and researchers. Finally, we describe the critical insight and expert knowledge that are required to make clinical decisions for individual patients, considering all of the parameters that must be considered to deliver personalised clinical management.
Liver cancer is a major cause of cancer mortality worldwide. Screening individuals at high risk, including those with cirrhosis and viral hepatitis, provides an avenue for improved survival, but ...current screening methods are inadequate. In this study, we used whole-genome cell-free DNA (cfDNA) fragmentome analyses to evaluate 724 individuals from the United States, the European Union, or Hong Kong with hepatocellular carcinoma (HCC) or who were at average or high-risk for HCC. Using a machine learning model that incorporated multifeature fragmentome data, the sensitivity for detecting cancer was 88% in an average-risk population at 98% specificity and 85% among high-risk individuals at 80% specificity. We validated these results in an independent population. cfDNA fragmentation changes reflected genomic and chromatin changes in liver cancer, including from transcription factor binding sites. These findings provide a biological basis for changes in cfDNA fragmentation in patients with liver cancer and provide an accessible approach for noninvasive cancer detection.
There is a great need for accessible and sensitive screening approaches for HCC worldwide. We have developed an approach for examining genome-wide cfDNA fragmentation features to provide a high-performing and cost-effective approach for liver cancer detection. See related commentary Rolfo and Russo, p. 532. This article is highlighted in the In This Issue feature, p. 517.
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