Mannose-Binding Lectin 2 as a Potential Therapeutic Target for Hepatocellular Carcinoma: Multi-Omics Analysis and Experimental Validation.

Mannose-binding lectin 2 (MBL2), a member of the multimeric lectin family, is crucial in immune regulation and tumor development. MBL2 gene polymorphisms are associated with the risk and prognosis of various tumors, including hepatocellular carcinoma (HCC). Its functional role in HCC remains largely unclear. In this study, we aimed to identify whether MBL2 is a key regulator and a potential therapeutic target for HCC. A bioinformatics analysis revealed close relationships among MBL2 downregulation, the tumor-associated proliferation and metastasis pathway, and tumor immunosuppressive microenvironments. Lower expression of MBL2 in HCC patients was linked to an unfavorable prognosis. A cell counting kit-8 assay, colony formation assay, transwell migration assay, and wound healing assay further confirmed that the overexpression of MBL2 could directly inhibit the proliferation and metastasis of HCC. Moreover, MBL2 expression was regulated by miR-34c-3p, as confirmed by the dual-luciferase reporter assay, thereby demonstrating tumor progression in HCC cells. Thus, our study offers the first comprehensive confirmation of the role of MBL2 in the development of HCC through multi-omics analysis and experimental validation. Furthermore, miR-34c-3p was found to be an upstream mechanism of the downregulation of MBL2 expression and could be a promising therapeutic target, expanding treatment options for patients with HCC.

Plasma-only circulating tumor DNA analysis detects minimal residual disease and predicts early relapse in hepatocellular carcinoma patients undergoing curative resection.

Background: Minimal residual disease (MRD) is considered an essential factor leading to relapse within 2 years (early relapse) after radical surgery, which is challenging to be detected by conventional imaging. Circulating tumor DNA (ctDNA) provides a novel approach for detecting MRD and predicting clinical outcomes. Here, we tried to construct a fixed panel for plasma-only ctDNA NGS to enable tumor-uninformed MRD detection in hepatocellular carcinoma (HCC). Methods: Here, we performed the followings: (i) profiling genomic alteration spectrum of ctDNA from the Chinese HCC cohort consisting of 493 individuals by NGS; (ii) screening of MRD monitoring genes; and (iii) performance evaluation of MRD monitoring genes in predicting early relapse in the ZJZS2020 cohort comprising 20 HCC patients who underwent curative resection. Results: A total of 493 plasma samples from the Chinese HCC cohort were detected using a 381/733-gene NGS panel to characterize the mutational spectrum of ctDNA. Most patients (94.1%, 464/493) had at least one mutation in ctDNA. The variants fell most frequently in TP53 (45.1%), LRP1B (20.2%), TERT (20.2%), FAT1 (16.2%), and CTNNB1 (13.4%). By customized filtering strategy, 13 MRD monitoring genes were identified, and any plasma sample with one or more MRD monitoring gene mutations was considered MRD-positive. In the ZJZS2020 cohort, MRD positivity presented a sensitivity of 75% (6/8) and a specificity of 100% (6/6) in identifying early postoperative relapse. The Kaplan-Meier analysis revealed a significantly short relapse-free survival (RFS; median RFS, 4.2 months vs. NR, P=0.002) in the MRD-positive patients versus those with MRD negativity. Cox regression analyses revealed MRD positivity as an independent predictor of poor RFS (HR 13.00, 95% CI 2.60-69.00, P=0.002). Conclusions: We successfully developed a 13-gene panel for plasma-only MRD detection, which was effective and convenient for predicting the risk of early postoperative relapse in HCC.

A new cell-free therapeutic strategy for liver regeneration: Human placental mesenchymal stem cell-derived extracellular vesicles.

Mesenchymal stem cells (MSCs) have potential role in organ regeneration therapy. Previous work indicating that MSCs confer protection against liver disease. Here, we aimed to determine the potential application in liver regeneration of human placenta-derived MSCs extracellular vesicles (hPMSCs-EVs) via experimental hepatectomy. hPMSCs-EVs were administered intravenously 24 h before 70% partial hepatectomy, the specific composition of hPMSCs-EVs was identified by sequencing and validated by the quantitative polymerase chain reaction, including circ-RBM23. The role of circ-RBM23 in L02 cell was evaluated and it was found that circ-RBM23 knockdown inhibited L02 cell proliferation both in vitro and in vivo. The competing endogenous RNA function of circ-RBM23 was evaluated by the RNA immunoprecipitation assay and found that circ-RBM23 shares miRNA response elements with RRM2. Overexpressed circ-RBM23 bound competitively to miR-139-5p, preventing the miRNA-mediated degradation of RRM2, activating the expression of eIF4G and AKT/mTOR, and facilitating liver regeneration. These results indicate that hPMSCs-EVs prevent hepatic dysfunction and improve liver regeneration in vivo and hepatocytes proliferation in vitro, potentially via circ-RBM23 delivery.

Abrogation of HnRNP L enhances anti-PD-1 therapy efficacy via diminishing PD-L1 and promoting CD8+ T cell-mediated ferroptosis in castration-resistant prostate cancer.

Owing to incurable castration-resistant prostate cancer (CRPC) ultimately developing after treating with androgen deprivation therapy (ADT), it is vital to devise new therapeutic strategies to treat CRPC. Treatments that target programmed cell death protein 1 (PD-1) and programmed death ligand-1 (PD-L1) have been approved for human cancers with clinical benefit. However, many patients, especially prostate cancer, fail to respond to anti-PD-1/PD-L1 treatment, so it is an urgent need to seek a support strategy for improving the traditional PD-1/PD-L1 targeting immunotherapy. In the present study, analyzing the data from our prostate cancer tissue microarray, we found that PD-L1 expression was positively correlated with the expression of heterogeneous nuclear ribonucleoprotein L (HnRNP L). Hence, we further investigated the potential role of HnRNP L on the PD-L1 expression, the sensitivity of cancer cells to T-cell killing and the synergistic effect with anti-PD-1 therapy in CRPC. Indeed, HnRNP L knockdown effectively decreased PD-L1 expression and recovered the sensitivity of cancer cells to T-cell killing in vitro and in vivo, on the contrary, HnRNP L overexpression led to the opposite effect in CRPC cells. In addition, consistent with the previous study, we revealed that ferroptosis played a critical role in T-cell-induced cancer cell death, and HnRNP L promoted the cancer immune escape partly through targeting YY1/PD-L1 axis and inhibiting ferroptosis in CRPC cells. Furthermore, HnRNP L knockdown enhanced antitumor immunity by recruiting infiltrating CD8+ T cells and synergized with anti-PD-1 therapy in CRPC tumors. This study provided biological evidence that HnRNP L knockdown might be a novel therapeutic agent in PD-L1/PD-1 blockade strategy that enhanced anti-tumor immune response in CRPC.

Correlation Between Circulating Tumor Cell DNA Genomic Alterations and Mesenchymal CTCs or CTC-Associated White Blood Cell Clusters in Hepatocellular Carcinoma.

PURPOSE: Liquid biopsy is attracting attention as a method of real-time monitoring of patients with tumors. It can be used to understand the temporal and spatial heterogeneity of tumors and has good clinical application prospects. We explored a new type of circulating tumor cell (CTC) enrichment technology combined with next-generation sequencing (NGS) to analyze the correlation between genomic alterations in circulating tumor cells of hepatocellular carcinoma and the counts of mesenchymal CTCs and CTC-associated white blood cell (CTC-WBC) clusters. METHODS: We collected peripheral blood samples from 29 patients with hepatocellular carcinoma from January 2016 to December 2019. We then used the CanPatrol™ system to capture and analyze mesenchymal CTCs and CTC-WBC clusters for all the patients. A customized Illumina panel was used for DNA sequencing and the Mann-Whitney U test was used to test the correlation between mesenchymal CTCs, CTC-WBC cluster counts, and specific genomic changes. RESULTS: At least one somatic hotspot mutation was detected in each of the 29 sequenced patients. A total of 42 somatic hot spot mutations were detected in tumor tissue DNA, and 39 mutations were detected in CTC-DNA, all of which included common changes in PTEN, MET, EGFR, RET, and FGFR3. The number of mesenchymal CTCs was positively correlated with the somatic genomic alterations in the PTEN and MET genes (PTEN, P = 0.021; MET, P = 0.008, Mann-Whitney U test) and negatively correlated with the somatic genomic alterations in the EGFR gene (P = 0.006, Mann-Whitney U test). The number of CTC-WBC clusters was positively correlated with the somatic genomic alterations in RET genes (P = 0.01, Mann-Whitney U test) and negatively correlated with the somatic genomic alterations in FGFR3 (P = 0.039, Mann-Whitney U test). CONCLUSIONS: We report a novel method of a CTC enrichment platform combined with NGS technology to analyze genetic variation, which further demonstrates the potential clinical application of this method for spatiotemporal heterogeneity monitoring of hepatocellular carcinoma. We found that the number of peripheral blood mesenchymal CTCs and CTC-WBC clusters in patients with hepatocellular carcinoma was related to a specific genome profile.

ABCC5 facilitates the acquired resistance of sorafenib through the inhibition of SLC7A11-induced ferroptosis in hepatocellular carcinoma.

Sorafenib is a first-line molecular-target drug for advanced hepatocellular carcinoma (HCC), and reducing sorafenib resistance is an important issue to be resolved for the clinical treatment of HCC. In the current study, we identified that ABCC5 is a critical regulator and a promising therapeutic target of acquired sorafenib resistance in human hepatocellular carcinoma cells. The expression of ABCC5 was dramatically induced in sorafenib-resistant HCC cells and was remarkably associated with poor clinical prognoses. The down-regulation of ABCC5 expression could significantly reduce the resistance of sorafenib to HCC cells. Importantly, activation of PI3K/AKT/NRF2 axis was essential for sorafenib to induce ABCC5 expression. ABCC5 increased intracellular glutathione (GSH) and attenuated lipid peroxidation accumulation by stabilizing SLC7A11 protein, which inhibited ferroptosis. Additionally, the inhibition of ABCC5 enhanced the anti-cancer activity of sorafenib in vitro and in vivo. These findings demonstrate a novel molecular mechanism of acquired sorafenib resistance and also suggest that ABCC5 is a new regulator of ferroptosis in HCC cells.

Circulating Tumor-Cell-Associated White Blood Cell Clusters in Peripheral Blood Indicate Poor Prognosis in Patients With Hepatocellular Carcinoma.

Aim: Circulating tumor cells (CTC) are a precursor to metastasis in several types of cancer and are occasionally found in the bloodstream in association with immune cells, such as white blood cells (WBCs). CTC-associated WBC (CTC-WBC) clusters can promote CTC appreciation and metastasis, suggesting that patients with CTC-WBC clusters found in the peripheral blood may have a worse prognosis. However, it is unclear whether CTC-WBC clusters are present in the peripheral blood of patients with hepatocellular carcinoma (HCC) and suggest a poor prognosis for HCC. Methods: We collected peripheral blood from 214 patients with HCC from January 2014 to December 2016. CanPatrol™ CTC analysis technology was used to isolate and count CTCs and CTC-WBC clusters in the patients' peripheral blood. Chi-squared analysis was used to calculate the correlation between the CTC-WBC clusters and clinicopathological characteristics. Kaplan-Meier survival analysis and Cox regression analysis were used to assess patient prognosis. Results: We used CanPatrol™ CTC analysis technology to count different types of CTCs and CTC-WBC clusters. The results showed that CTC-WBC clusters and tumor size (P = 0.001), tumor number (P = 0.005), portal vein tumor thrombus (P = 0.026), BCLC stage (P < 0.001), AFP level (P = 0.002), and total number of CTCs (P < 0.001) were statistically related. Cox regression analysis revealed that CTC-WBC clusters are an independent prognostic indicator of DFS (HR = 1.951, 95%CI:1.348-2.824, P < 0.001) and OS (HR = 3.026, 95%CI:1.906-4.802, P < 0.001) in HCC patients. Using Kaplan-Meier analysis, we found that positive CTC-WBC cluster patients had significantly shorter DFS and OS than patients with negative CTC-WBC (P < 0.001 and P < 0.001, respectively). Conclusions: CTC-WBC clusters in the peripheral blood are an independent predictor of DFS and OS, and their presence indicates poor prognosis in patients with HCC.

Correction to: Pre-metastatic niche triggers SDF-1/CXCR4 axis and promotes organ colonisation by hepatocellular circulating tumour cells via downregulation of Prrx1.

An amendment to this paper has been published and can be accessed via the original article.

Pre-metastatic niche triggers SDF-1/CXCR4 axis and promotes organ colonisation by hepatocellular circulating tumour cells via downregulation of Prrx1.

BACKGROUND: Circulating tumour cells (CTCs), especially mesenchymal CTCs, are important determinants of metastasis, which leads to most recurrence and mortality in hepatocellular carcinoma (HCC). However, little is known about the underlying mechanisms of CTC colonisation in pre-metastatic niches. METHODS: Detection and classification of CTCs in patients were performed using the CanPatrol™ system. A lentiviral vector expressing Prrx1-targeting shRNA was constructed to generate a stable HCC cell line with low expression of Prrx1. The effect of Prrx1 knockdown on stemness, migration, and drug resistance of the cell line was assessed, including involvement of SDF-1/CXCR4 signalling. Promising clinical applications of an inhibitor of STAT3 tyrosine phosphorylation, C188-9, and specific blockade with CXCR4 antibody were explored. RESULTS: The number of mesenchymal CTCs in blood was closely associated with tumour recurrence or metastasis. Pre-metastatic niche-derived SDF-1 could downregulate Prrx1, which induced the stemness, drug resistance, and increased expression of CXCR4 in HCC cells through the STAT3 pathway in vitro. In vivo, mice bearing tumours of Prrx1 low-expressing cells had significantly shorter survival. In xenograft tumours and clinical samples, loss of Prrx1 was negatively correlated with increased expression of CXCR4 in lung metastatic sites compared with that in the primary foci. CONCLUSIONS: These findings demonstrate that decreased expression of Prrx1 stimulates SDF-1/CXCR4 signalling and contributes to organ colonisation with blood CTCs in HCC. STAT3 inhibition and specific blockade of CXCR4 have clinical potential as therapeutics for eliminating organ metastasis in advanced HCC.