Search

Patients with hepatocellular carcinoma (HCC) have poor long-term survival following curative resection because of the high rate of tumor early recurrence. Little is known about the trajectory of genomic evolution from primary to early-recurrent HCC. In this study, we performed whole-genome sequencing (WGS) on 40 pairs of primary and early-recurrent hepatitis B virus (HBV)-related HCC tumors from patients who received curative resection, and from four patients whose primary and recurrent tumor were extensively sampled. We identified two recurrence patterns: de novo recurrence (18/40), which developed genetically independently of the primary tumor and carried different HCC drivers, and ancestral recurrence (22/40), which was clonally related to the primary tumor and progressed more rapidly than de novo recurrence. We found that the recurrence location was predictive of the recurrence pattern: distant recurrence tended to display the de novo pattern, whereas local recurrence tended to display the ancestral pattern. We then uncovered the evolutionary trajectories based on the subclonal architecture, driver-gene mutations, and mutational processes observed in the primary and recurrent tumors. Multi-region WGS demonstrated spatiotemporal heterogeneity and polyclonal, monophyletic dissemination in HCC ancestral recurrence. In addition, we identified recurrence-specific mutations and copy-number gains in BCL9, leading to WNT/β-catenin signaling activation and an immune-excluded tumor microenvironment, which suggests that BCL9 might serve as a new therapeutic target for recurrent HCC. Collectively, our results allow us to view with unprecedented clarity the genomic evolution during HBV-related HCC early recurrence, providing an important molecular foundation for enhanced understanding of HCC with implications for personalized therapy to improve patient survival.

Sarcomatoid hepatocellular carcinoma (sHCC) is a rare type of liver malignancy. Currently, the tumor immune features of sHCC are poorly understood. We recruited 31 patients with resected sHCC for whom tissue samples and complete clinicopathologic and follow-up data were available. To understand the immune infiltration of sHCC, immunohistochemical staining was performed on the resected sHCC samples to compare the expressions of programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), B7-H3, indoleamine 2,3-dioxygenase (IDO), lymphocyte-activation gene 3 (LAG-3), CD8, FOXP3, and CD68 in tumor and peritumoral tissues. Kaplan-Meier and Cox regression analyses were used to assess the predictive value of immune markers. Sarcomatoid components were characterized with significantly higher expression of PD-L1 and B7-H3 in tumor cells than in conventional HCC components, as well as in peritumoral tissue. Additionally, sarcomatoid components had a higher density of FOXP3+ and LAG-3+ cells and a lower density of CD8+ cells than conventional HCC components or peritumoral tissue. Higher expression of PD-L1 in tumor cells significantly correlated with higher densities of CD8+, PD-1+, and LAG-3+ cells. Increased tumor PD-L1 expression and decreased CD8+ T-cell density were associated with poor overall survival (OS) and disease-free survival (DFS) in patients of sHCC. These findings suggest further characterization on relative mechanism of sHCC immune infiltration may identify therapeutic targets for immunotherapy.

Background & aims Intrahepatic cholangiocarcinoma (ICC) is aggressive and has high rates of relapse, conferring poor long-term survival after curative resection. Little is known about the genomic evolution that occurs during ICC relapse. Approach & results We conducted whole-exome sequencing (WES) of 30 paired primary and relapsed tumors from 10 patients with ICC who received curative resection. We sought to identify frequently altered genes, infer tumor subclonal architectures, and track genomic evolution from primary to relapsed tumors. We examined functional effects and the mechanism of action of SLIT2, a gene specifically mutated in relapsed tumors, on tumor growth and metastasis and the tumor microenvironment. Our results indicated that relapsed ICCs were genetically derived from intrahepatic dissemination of primary tumors. But, they acquired additional mutations while maintaining most drivers, such as TP53 and IDH1. Multiregion sequencing suggested polyclonal seeding of ICC dissemination. Four of 10 relapsed ICCs acquired SLIT2 mutations that were not present in the corresponding primary tumors. Validation in an expanded sample revealed SLIT2 mutations in 2.3% (1/44) of primary ICCs and 29.5% (13/44) of relapsed ICCs. Biofunctional investigations revealed that inactivating mutation of SLIT2 resulted in activation of PI3K-Akt signaling in ICC cells, directly enhanced neutrophil chemotaxis, mediated tumor-associated neutrophil infiltration, and contributed to ICC growth and metastasis. Conclusions We characterized genomic evolution during ICC relapse and identified SLIT2 as a driver of tumor dissemination and tumor-associated neutrophil infiltration.

Background Long noncoding RNAs (lncRNAs) are functionally associated with cancer development and progression. Although gene copy number variation (CNV) is common in hepatocellular carcinoma (HCC), it is not known how CNV in lncRNAs affects HCC progression and recurrence. We aimed to identify a CNV‐related lncRNA involved in HCC progression and recurrence and illustrate its underlying mechanisms and prognostic value. Methods We analyzed the whole genome sequencing (WGS) data of matched cancerous and noncancerous liver samples from 49 patients with HCC to identify lncRNAs with CNV. The results were validated in another cohort of 238 paired HCC and nontumor samples by TaqMan copy number assay. We preformed Kaplan‐Meier analysis and log‐rank test to identify lncRNA CNV with prognostic value. We conducted loss‐ and gain‐of‐function studies to explore the biological functions of LINC01133 in vitro and in vivo. The competing endogenous RNAs (ceRNAs) mechanism was clarified by microRNA sequencing (miR‐seq), quantitative real‐time PCR (qRT‐PCR), western blot, and dual‐luciferase reporter assays. We confirmed the binding mechanism between lncRNA and protein by RNA pull‐down, RNA immunoprecipitation, qRT‐PCR, and western blot analyses. Results Genomic copy numbers of LINC01133 were increased in HCC, which were positively related with the elevated expression of LINC01133. Increased copy number of LINC01133 predicted the poor prognosis in HCC patients. LINC01133 overexpression in HCC cells promoted proliferation and aggressive phenotypes in vitro, and facilitated tumor growth and lung metastasis in vivo, whereas LINC01133 knockdown had the opposite effects. LINC01133 sponged miR‐199a‐5p, resulting in enhanced expression of SNAI1, which induced epithelial‐to‐mesenchymal transition (EMT) in HCC cells. In addition, LINC01133 interacted with Annexin A2 (ANXA2) to activate the ANXA2/STAT3 signaling pathway. Conclusions LINC01133 promotes HCC progression by sponging miR‐199a‐5p and interacting with ANXA2. LINC01133 CNV gain is predictive of poor prognosis in patients with HCC., Genomic copy numbers of LINC01133 were increased in HCC, which were positively related with its elevated expression, and LINC01133 CNV gain predicted the poor prognosis in HCC patients. LINC01133 sponged miR‐199a‐5p, resulting in enhanced expression of SNAI1, which induced EMT in HCC cells. LINC01133 interacted with ANXA2 to activate ANXA2/STAT3 signaling pathway.

BackgroundTumor-associated neutrophils (TANs) and macrophages (TAMs) can each influence cancer growth and metastasis, but their combined effects in intrahepatic cholangiocarcinoma (ICC) remain unclear.MethodsWe explored the distributions of TANs and TAMs in patient-derived ICC samples by multiplex immunofluorescent staining and tested their separate and combined effects on ICC in vitro and in vivo. We then investigated the mechanistic basis of the effects using PCR array, western blot analysis and ELISA experiments. Finally, we validated our results in a tissue microarray composed of primary tumor tissues from 359 patients with ICC.ResultsThe spatial distributions of TANs and TAMs were correlated with each other in patient-derived ICC samples. Interaction between TANs and TAMs enhanced the proliferation and invasion abilities of ICC cells in vitro and tumor progression in a mouse xenograft model of ICC. TANs and TAMs produced higher levels of oncostatin M and interleukin-11, respectively, in co-culture than in monoculture. Both of those cytokines activated STAT3 signaling in ICC cells. Knockdown of STAT3 abolished the protumor effect of TANs and TAMs on ICC. In tumor samples from patients with ICC, increased TAN and TAM levels were correlated with elevated p-STAT3 expression. All three of those factors were independent predictors of patient outcomes.ConclusionsTANs and TAMs interact to promote ICC progression by activating STAT3.

Background: Long non-coding RNAs (lncRNAs) have been found to be functionally associated with cancer development and progression. Although copy number variations (CNVs) are common in hepatocellular carcinoma (HCC), little is known about how CNVs in lncRNAs affect HCC progression and recurrence.Methods: We analyzed the whole genome sequencing (WGS) data of matched cancerous and non-cancerous liver samples from 49 patients with HCC to identify lncRNAs with CNVs. The results were validated in another cohort of 238 paired HCC and non-tumor samples by TaqMan copy number assay. Kaplan-Meier analysis and the log-rank test were performed to determine the prognostic value of CNVs in lincRNAs. Loss- and gain-of-function studies were conducted to determine the biological functions of LINC01133 in vitro and in vivo. The competing endogenous RNAs (ceRNAs) mechanism was clarified by microRNA sequencing (miR-seq), quantitative real-time PCR (qRT-PCR), western blot, and dual-luciferase reporter analyses. The protein binding mechanism was confirmed by RNA pull-down, RNA immunoprecipitation (RIP), qRT-PCR, and western blot analyses.Results: Genomic copy number of LINC01133 was increased in HCC, which is positively related with the elevated expression of LINC01133. Increased copy number of LINC01133 predicted the poor prognosis in HCC patients. LINC01133 overexpression promoted proliferation, colony formation, migration, and invasion in vitro, and facilitated tumor growth and lung metastasis in vivo, whereas LINC01133 knockdown had the opposite effects. Mechanistically, LINC01133 acted as a sponge of miR-199a-5p, resulting in enhanced expression of SNAI1, which induced epithelial-mesenchymal transition (EMT) in HCC cells. In addition, LINC01133 interacted with Annexin A2 (ANXA2) to activate ANXA2/STAT3 signaling pathway.Conclusions: LINC01133 promotes HCC progression by sponging miR-199a-5p and interacting with ANXA2. LINC01133 CNV gain is predictive of poor prognosis in HCC patients undergoing curative resection.

Background Plasmacytoid dendritic cells (pDCs) are present in various primary and metastatic human neoplasms; however, their clinical significance in intrahepatic cholangiocarcinoma is not clear. Methods To evaluate pDCs’ distributions in and around tumors as well as their potential function and predictive value for prognosis in patients undergoing curative resection, we performed immunohistochemistry to examine the expression of pDC marker BDCA2, and CD3, CD4, CD8 and Foxp3 in intratumoral and peritumoral tissues from 359 patients with intrahepatic cholangiocarcinoma and compared with prognostic and clinicopathologic factors. Results Results showed that patients with high numbers of BDCA2+ pDCs in peritumoral tissues were more likely to have elevated levels of carbohydrate antigen 19-9 and gamma-glutamyl transferase, larger and more tumors, advanced tumor-node-metastasis staging, more vascular/bile duct invasion, and lymphatic metastasis in association with greater chance of recurrence and shorter overall survival. Peritumoral tissues with larger numbers of pDCs also showed increased Foxp3+ regulatory T cell infiltration, both of which were found to be independent factors for predicting time to recurrence and overall survival. By contrast, patient outcomes were not associated with the presence of intratumoral pDCs. Conclusions Peritumoral pDC infiltration may indicate an immune tolerogenic peritumor microenvironment and can be used to predict a poor prognosis for patients undergoing curative resection for intrahepatic cholangiocarcinoma.

Recent studies suggested that the immune microenvironment and mutational landscape are associated with the response to immune-based therapy in several types of cancer. The roles of those factors in Chinese HCC remain largely unknown. In this study, we obtained 182 FFPE samples of HCC cohort that were previously subjected to NGS (49 WGS, 18 WES, and 115 targeted sequencing). We performed immunohistochemistry to detect CD3, CD4, CD8, CD57, Foxp3, CD68, CD66b, and PD-L1 expression in the samples. We identified diverse associations between the mutational landscape and the immune microenvironment in the HCC samples. High mutational burden and an aristolochic acid-dominated mutational signature were both correlated with elevated tumoral PD-L1 expression and CD3+ T-cell infiltration and high numbers of CD68+ TAMs and CD66b+ TANs. CD4+ and CD8+ T cells exhibited lower infiltration levels in tumors with mutations in AXIN1/CTNNB1 and in tumors with aflatoxin-dominant mutational signatures. Moreover, tumors with TP53 mutations had less CD8+ T-cell infiltration and more Foxp3+ Treg-cell infiltration than those without TP53 mutations. Kaplan–Meier survival analysis revealed that the presence of CD8+, Foxp3+, CD66b+, or CD68+ immune cells; tumoral PD-L1 expression alone; or the presence of CD8+ or Foxp3+ cells combined with TP53 mutation were predictive of recurrence and poor overall survival after curative resection. In conclusion, the association between the mutational landscape and the immune microenvironment warrants further analysis to determine its impact on patient outcomes to guide personalized immune-based therapy for Chinese patients with HCC.

Structural variations (SVs) influence the development and progression of multiple types of cancer. The genes affected by SVs in hepatocellular carcinoma (HCC) and their contribution to tumor growth and metastasis remain unknown. In this study, through whole-genome sequencing (WGS), we identified MACROD2 as the gene most frequently affected by SVs, which were associated with low MACROD2 expression levels. Low MACROD2 expression was predictive of tumor recurrence and poor overall survival. MACROD2 expression was decreased in HCC cell lines, especially those with high metastatic potential. MACROD2 knockdown in HCC cells markedly enhanced proliferation and invasiveness in vitro and tumor progression in vivo and promoted epithelial–mesenchymal transition (EMT). By contrast, MACROD2 overexpression reversed EMT and inhibited HCC growth and metastasis. Mechanistically, MACROD2 deficiency suppressed glycogen synthase kinase-3β (GSK-3β) activity and activated β-catenin signaling, which mediated the effect of MACROD2 on HCC. In clinical HCC samples, decreased MACROD2 expression was correlated with the activation of GSK-3β/β-catenin signaling and the EMT phenotype. Overall, our results revealed that MACROD2 is frequently affected by SVs in HCC, and its deficiency promotes tumor growth and metastasis by activating GSK-3β/β-catenin signaling.

Background and aims There is growing evidence that single-stranded, circular RNA (circRNA) plays a key role in the development of certain cancers, including hepatocellular carcinoma (HCC). It is less clear, however, what role circRNA plays in HCC metastasis. Approach and results In this study, through circRNA sequencing, we identified a circRNA: circASAP1 (a circRNA derived from exons 2 and 3 of the ASAP1 gene, hsa_circ_0085616), which is associated with pulmonary metastasis after curative resection in patients with HCC. CircASAP1 was overexpressed in HCC cell lines with high metastatic potential and in metastatic HCCs. In vitro, circASAP1 promoted cell proliferation, colony formation, migration, and invasion, and in vivo, it enhanced tumor growth and pulmonary metastasis. Mechanism studies showed that circASAP1 acts as a competing endogenous RNA for microRNA 326 (miR-326) and microRNA 532-5p (miR-532-5p), both of which are tumor suppressors in HCC. We found that mitogen-activated protein kinase (MAPK) 1 and colony stimulating factor (CSF)-1 were direct common targets for microRNA 326 (miR-326) and microRNA 532-5p (miR-532-5p), which were regulated by circASAP1. CircASAP1 promotes HCC cell proliferation and invasion by regulating miR-326/miR-532-5p-MAPK1 signaling and, furthermore, mediates tumor-associated macrophage infiltration by regulating the miR-326/miR-532-5p-CSF-1 pathway. Clinical HCC samples exhibited a positive correlation between circASAP1 expression and levels of CSF-1, MAPK1, and CD68+ tumor-associated macrophages, all of which were predictive of patient outcomes. Conclusion We identified circASAP1 as a key regulator of HCC metastasis that acts on miR-326/miR-532-5p-MAPK1/CSF-1 signaling and serves as a prognostic predictor in patients with HCC.

Plasmacytoid dendritic cells (pDCs) are present in various primary and metastatic human neoplasms; however, their clinical significance in hepatocellular carcinoma (HCC) is unclear. In this study, we investigated the distribution, prognostic value, and potential function of pDCs in HCC patients undergoing curative resection. We performed immunohistochemical analyses of whole tumor sections from 224 patients to assess the expression of BDCA2, CD3, CD4, CD8, Foxp3, granzyme B, IL-17, and CD34. The findings were validated using tissue microarrays from another two independent cohorts totaling 841 HCC patients undergoing curative resection. Our results demonstrated that high numbers of BDCA2+ pDCs within tumors correlated with high alpha-fetoprotein levels, greater vascular invasion, advanced tumor-node-metastasis stage, shorter overall survival, and a higher recurrence rate. However, patient outcomes were not associated with pDCs in peritumoral stromal or nontumor tissues. Furthermore, an increase in intratumoral pDCs was associated with increased intratumoral infiltration of Foxp3+ regulatory T cells and IL-17-producing cells and correlated with tumor vascular density. Univariate and multivariate analyses revealed that the presence of intratumoral pDCs alone or in combination with regulatory T and/or IL-17-producing cells was an independent predictor of time to recurrence and overall survival. In conclusion, our study demonstrated that intratumoral infiltration by pDCs is a novel indicator for poor prognosis in patients with HCC, possibly through the induction of an immune tolerogenic and inflammatory tumor microenvironment comprising regulatory T and IL-17-producing cells. An assessment of the combination of these cells represents a superior predictor of patient outcome.