Genomic and Epigenomic Features of Primary and Recurrent Hepatocellular Carcinomas

Development and Validation of a Nomogram for Patients Undergoing Transarterial Chemoembolization for Recurrent Hepatocellular Carcinoma After Hepatectomy

Purpose

This study aims to establish a prognostic nomogram for patients who underwent transarterial chemoembolization (TACE) for recurrent hepatocellular carcinoma (HCC) after hepatectomy.

Patients and Methods

Patients who underwent TACE for recurrent early- and middle-stage HCC after hepatectomy between 2009.01 and 2015.12 were included. Enrolled patients were randomly divided into training (n=345) and validation (n=173) cohorts according to a computer-generated randomized number. Independent factors for overall survival (OS) were determined and included in the nomogram based on the univariate and multivariate analyses of the training group. The nomogram was validated and compared to other prognostic models. Discriminative ability and predictive accuracy were determined using the Harrell C index (C-index), area under the receiver operating characteristic curve (AUROC), and calibration curve.

Results

The final nomogram was established based on four parameters including resection-to-TACE time interval, recurrent tumor diameter, recurrent tumor number, and AFP level. The C-indexes of the nomogram for predicting OS were 0.67 (95% CI 0.63-0.70) and 0.71 (95% CI 0.68-0.74) in the training and validation cohort respectively. The AUROCs for predicting the 1-year, 2-year and 3-year OS based on the nomogram were also superior to those of the other models. The calibration curve for 3-year survival showed a high congruence between the predicted and actual survival probabilities. According to the scores calculated by the nomogram, patients were stratified into three subgroups: high-risk (scoring ≥53 points), middle-risk (scoring ≥26 and <53 points), and low-risk (scoring <26 points) subgroups with a median OS of 10.1 (95% CI 0.63-0.70), 20.3 (95% CI 17.5-22.5) and 47.0 (95% CI 34.2-59.8) months, respectively.

Conclusion

The proposed nomogram served as a new tool to predict individual survival in patients who underwent TACE for recurrent HCC after hepatectomy, with favorable performance and discrimination. For high-risk patients, treatment should be optimized beyond TACE alone based on the nomogram.

Poor clinical outcomes and immunoevasive contexture in CD161+CD8+ T cells barren human pancreatic cancer

BACKGROUND

The role of CD161 expression on CD8+ T cells in tumor immunology has been explored in a few studies, and the clinical significance of CD161+CD8+ T cells in pancreatic ductal adenocarcinoma (PDAC) remains unclear. This study seeks to clarify the prognostic value and molecular characteristics linked to CD161+CD8+ T cell infiltration in PDAC.

METHODS

This study included 186 patients with confirmed PDAC histology after radical resection. CD161+CD8+ T cell infiltration was assessed using immunofluorescence staining on tumor microarrays. Flow cytometry and single-cell RNA sequencing were used to evaluate their functional status.

RESULTS

We observed significant associations between tumor-infiltrating CD161+CD8+ T cells and clinicopathological factors, such as tumor differentiation, perineural invasion, and serum CA19-9 levels. Patients with higher tumor-infiltrating CD161+CD8+ T cell levels had longer overall survival (OS) and recurrence-free survival (RFS) than those with lower levels. Multivariable analysis confirmed tumor-infiltrating CD161+CD8+ T cell as an independent prognostic indicator for both OS and RFS. Notably, a combination of tumor-infiltrating CD161+CD8+ T cell and CA19-9 levels showed a superior power for survival prediction, and patients with low tumor-infiltrating CD161+CD8+ T cell and high CA19-9 levels had the worst survival. Furthermore, lower tumor-infiltrating CD161+CD8+ T cells were associated with a better response to adjuvant chemotherapy. Finally, we identified tumor-infiltrating CD161+CD8+ T cells as a unique subtype of responsive CD8+ T cells characterized by increased levels of cytotoxic cytokines and immune checkpoint molecules.

CONCLUSION

CD161+CD8+ T cells exhibit elevated levels of both cytotoxic and immune-checkpoint molecules, indicating as a potential and attractive target for immunotherapy. The tumor-infiltrating CD161+CD8+ T cell is a valuable and promising predictor for survival and therapeutic response to adjuvant chemotherapy in PDAC. Further research is warranted to validate its role in the risk stratification and optimization of therapeutic strategies.

Genomic and transcriptomic profiling reveals key molecules in metastatic potentials and organ-tropisms of hepatocellular carcinoma

Metastasis is a landmark event for rapid postsurgical relapse and death of HCC patients. Although distinct genomic and transcriptomic profiling of HCC metastasis had been reported previously, the causal relationships of somatic mutants, mRNA levels and metastatic potentials were difficult to be established in clinic. Therefore, 11 human HCC cell lines and 7 monoclonal derivatives with definite metastatic potentials and tropisms were subjected to whole exome sequencing (WES) and whole transcriptome sequencing (WTS). TP53, MYO5A, ROS1 and ARID2 were the prominent mutants of metastatic drivers in HCC cells. During HCC clonal evaluation, TP53, MYO5A and ROS1 mutations occurred in the early stage, EXT2 and NIN in the late stage. NF1 mutant was unique in lung tropistic cell lines, RNF126 mutant in lymphatic tropistic ones. PER1, LMO2, GAS7, NR4A3 expression levels were positively associated with relapse-free survival (RFS) of HCC patients. The integrative analysis revealed 58 genes exhibited both somatic mutation and dysregulated mRNA levels in high metastatic cells. Altogether, metastatic drivers could accumulate gradually at different stages during HCC progression, some drivers might modulate HCC metastatic potentials and the others regulate metastatic tropisms.

Molecular characterization of an embryonal rhabdomyosarcoma occurring in a patient with Kabuki syndrome: report and literature review in the light of tumor predisposition syndromes

Kabuki syndrome is a well-recognized syndrome characterized by facial dysmorphism and developmental delay/intellectual disability and in the majority of patients a germline variant in KMT2D is found. As somatic KMT2D variants can be found in 5-10% of tumors a tumor predisposition in Kabuki syndrome is discussed. So far less than 20 patients with Kabuki syndrome and a concomitant malignancy have been published. Here we report on a female patient with Kabuki syndrome and a c.2558_2559delCT germline variant in KMT2D who developed an embryonal rhabdomyosarcoma (ERMS) at 10 years. On tumor tissue we performed DNA-methylation profiling and exome sequencing (ES). Copy number analyses revealed aneuploidies typical for ERMS including (partial) gains of chromosomes 2, 3, 7, 8, 12, 15, and 20 and 3 focal deletions of chromosome 11p. DNA methylation profiling mapped the case to ERMS by a DNA methylation-based sarcoma classifier. Sequencing suggested gain of the wild-type KMT2D allele in the trisomy 12. Including our patient literature review identified 18 patients with Kabuki syndrome and a malignancy. Overall, the landscape of malignancies in patients with Kabuki syndrome was reminiscent of that of the pediatric population in general. Histopathological and molecular data were only infrequently reported and no report included next generation sequencing and/or DNA-methylation profiling. Although we found no strong arguments pointing towards KS as a tumor predisposition syndrome, based on the small numbers any relation cannot be fully excluded. Further planned studies including profiling of additional tumors and long term follow-up of KS-patients into adulthood could provide further insights.

MYC and MET cooperatively drive hepatocellular carcinoma with distinct molecular traits and vulnerabilities

Enhanced activation of the transcription factor MYC and of the receptor tyrosine kinase MET are among the events frequently occurring in hepatocellular carcinoma (HCC). Both genes individually act as drivers of liver cancer initiation and progression. However, their concomitant alteration in HCC has not been explored, nor functionally documented. Here, we analysed databases of five independent human HCC cohorts and found a subset of patients with high levels of MYC and MET (MYC^high/MET^high) characterised by poor prognosis. This clinical observation drove us to explore the functionality of MYC and MET co-occurrence in vivo, combining hydrodynamic tail vein injection for MYC expression in the R26^stopMet genetic setting, in which wild-type MET levels are enhanced following the genetic deletion of a stop cassette. Results showed that increased MYC and MET expression in hepatocytes is sufficient to induce liver tumorigenesis even in the absence of pre-existing injuries associated with a chronic disease state. Intriguingly, ectopic MYC in MET tumours increases expression of the Mki67 proliferation marker, and switches them into loss of Afp, Spp1, Gpc3, Epcam accompanied by an increase in Hgma1, Vim, and Hep-Par1 levels. We additionally found a switch in the expression of specific immune checkpoints, with an increase in the Ctla-4 and Lag3 lymphocyte co-inhibitory responses, and in the Icosl co-stimulatory responses of tumour cells. We provide in vitro evidence on the vulnerability of some human HCC cell lines to combined MYC and MET targeting, which are otherwise resistant to single inhibition. Mechanistically, combined blockage of MYC and MET converts a partial cytostatic effect, triggered by individual blockage of MYC or MET, into a cytotoxic effect. Together, these findings highlight a subgroup of HCC characterised by MYC^high/MET^high, and document functional cooperativity between MYC and MET in liver tumorigenesis. Thus, the MYC-R26^Met model is a relevant setting for HCC biology, patient classification and treatment.

Use of radiomics containing an effective peritumoral area to predict early recurrence of solitary hepatocellular carcinoma ≤5 cm in diameter

Background

Hepatocellular carcinoma (HCC) is the sixth leading type of cancer worldwide. We aimed to develop a preoperative predictive model of the risk of early tumor recurrence after HCC treatment based on radiomic features of the peritumoral region and evaluate the performance of this model against postoperative pathology.

Method

Our model was developed using a retrospective analysis of imaging and clinicopathological data of 175 patients with an isolated HCC ≤5 cm in diameter; 117 patients were used for model training and 58 for model validation. The peritumoral area was delineated layer-by-layer for the arterial and portal vein phase on preoperative dynamic enhanced computed tomography images. The volume area of interest was expanded by 5 and 10 mm and the radiomic features of these areas extracted. Lasso was used to select the most stable features.

Results

The radiomic features of the 5-mm area were sufficient for prediction of early tumor recurrence, with an area under the curve (AUC) value of 0.706 for the validation set and 0.837 for the training set using combined images. The AUC of the model using clinicopathological information alone was 0.753 compared with 0.786 for the preoperative radiomics model (P >0.05).

Conclusions

Radiomic features of a 5-mm peritumoral region may provide a non-invasive biomarker for the preoperative prediction of the risk of early tumor recurrence for patients with a solitary HCC ≤5 cm in diameter. A fusion model that combines the radiomic features of the peritumoral region and postoperative pathology could contribute to individualized treatment of HCC.

Personalized treatment for hepatocellular carcinoma: Current status and future perspectives

Systemic treatment for hepatocellular carcinoma (HCC) has been advancing rapidly over the last decade. More novel agents, including both targeted agents and immune checkpoint inhibitors, are available for physicians to use sequentially or concurrently for patients with advanced HCC. Despite more options, only a proportion of patients benefit from each regimen. Therefore, clinicians are facing challenges on how to choose the right regimen for the right patient with HCC, which raises the importance of personalized treatment approach. To advance personalized treatment for HCC, one approach relies on the acquisition of biomarker data from clinical trials to evaluate clinical parameters or genotypes in association with outcomes of selected drugs. This approach has led to finding of high baseline alpha-fetoprotein levels in association with benefits of ramucirumab. Cumulative findings from multiple clinical trials and translational studies also suggest that selected etiology and/or genotype of HCC could predict resistance to immune checkpoint inhibitors. The second approach is to decipher the tumor heterogeneity of HCC with an aim to identify clinically relevant patterns to guide clinical decisions. Tumor heterogeneity could exist within a single tumor (intra-tumoral heterogeneity), among different tumors in the same patient (inter-tumoral heterogeneity) or between primary and recurrent tumors (temporal tumor heterogeneity). The analyses of tumor heterogeneity have also been powered by coverage of tumor immune environment and incorporation of circulating tumor nucleic acid technology. Emerging publications have been reported above tumor heterogeneity exist in HCC, which is potentially clinically impactful.

The Role of Chronic Liver Diseases in the Emergence and Recurrence of Hepatocellular Carcinoma: An Omics Perspective

Hepatocellular carcinoma (HCC) typically develops from a background of cirrhosis resulting from chronic inflammation. This inflammation is frequently associated with chronic liver diseases (CLD). The advent of next generation sequencing has enabled extensive analyses of molecular aberrations in HCC. However, less attention has been directed to the chronically inflamed background of the liver, prior to HCC emergence and during recurrence following surgery. Hepatocytes within chronically inflamed liver tissues present highly activated inflammatory signaling pathways and accumulation of a complex mutational landscape. In this altered environment, cells may transform in a stepwise manner toward tumorigenesis. Similarly, the chronically inflamed environment which persists after resection may impact the timing of HCC recurrence. Advances in research are allowing an extensive epigenomic, transcriptomic and proteomic characterization of CLD which define the emergence of HCC or its recurrence. The amount of data generated will enable the understanding of oncogenic mechanisms in HCC from the CLD perspective and provide the possibility to identify robust biomarkers or novel therapeutic targets for the treatment of primary and recurrent HCC. Importantly, biomarkers defined by the analysis of CLD tissue may permit the early detection or prevention of HCC emergence and recurrence. In this review, we compile the current omics based evidence of the contribution of CLD tissues to the emergence and recurrence of HCC.