Immune checkpoint blockade for the treatment of human hepatocellular carcinoma

Characterization of HCC Mouse Models: Towards an Etiology-Oriented Subtyping Approach

Murine liver tumors often fail to recapitulate the complexity of human hepatocellular carcinoma (HCC), which might explain the difficulty to translate preclinical mouse studies into clinical science. The aim of this study was to evaluate a subtyping approach for murine liver cancer models with regard to etiology-defined categories of human HCC, comparing genomic changes, histomorphology, and IHC profiles. Sequencing and analysis of gene copy-number changes [by comparative genomic hybridization (CGH)] in comparison with etiology-dependent subsets of HCC patients of The Cancer Genome Atlas (TCGA) database were conducted using specimens (75 tumors) of five different HCC mouse models: diethylnitrosamine (DEN) treated wild-type C57BL/6 mice, c-Myc and AlbLTαβ transgenic mice as well as TAK1^LPC-KO and Mcl-1^Δhep mice. Digital microscopy was used for the assessment of morphology and IHC of liver cell markers (A6-CK7/19, glutamine synthetase) in mouse and n = 61 human liver tumors. Tumor CGH profiles of DEN-treated mice and c-Myc transgenic mice matched alcohol-induced HCC, including morphologic findings (abundant inclusion bodies, fatty change) in the DEN model. Tumors from AlbLTαβ transgenic mice and TAK1^LPC-KO models revealed the highest overlap with NASH-HCC CGH profiles. Concordant morphology (steatosis, lymphocyte infiltration, intratumor heterogeneity) was found in AlbLTαβ murine livers. CGH profiles from the Mcl-1^Δhep model displayed similarities with hepatitis-induced HCC and characteristic human-like phenotypes (fatty change, intertumor and intratumor heterogeneity). IMPLICATIONS: Our findings demonstrate that stratifying preclinical mouse models along etiology-oriented genotypes and human-like phenotypes is feasible. This closer resemblance of preclinical models is expected to better recapitulate HCC subgroups and thus increase their informative value.

Spontaneous regression of hepatocellular carcinoma with reduction in angiogenesis-related cytokines after treatment with sodium-glucose cotransporter 2 inhibitor in a cirrhotic patient with diabetes mellitus

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare event, and the pathogenesis remains unclear. Here, we present a case of spontaneous regression of HCC after treatment with sodium-glucose cotransporter 2 inhibitor (SGLT2i) in a cirrhotic patient with diabetes mellitus (DM). A 68-year-old man regularly visited our hospital for follow-up of HCC after treatment with transcatheter arterial chemoembolization, and management of liver cirrhosis and type 2 DM. Contrast-enhanced computed tomography scan showed a hypervascular tumor in the liver and elevated serum α-fetoprotein levels, indicating the recurrence of HCC. Simultaneously, the hemoglobin A1c value increased to 8.0%; therefore, he was treated with SGLT2i (canagliflozin 100 mg/day). Ten weeks after the initiation of SGLT2i treatment, he was admitted to our hospital for treatment of recurrent HCC. However, the hypervascular tumor had disappeared, and the elevated serum α-fetoprotein level had decreased to normal limits, indicating spontaneous regression of HCC. In addition, an angiogenesis array analysis revealed downregulated protein expression of matrix metalloproteinase-8, angiopoietin-1/2, platelet-derived growth factor-AA, and prolactin at 10 weeks after SGLT2i treatment. In this report, we first describe a case of spontaneous regression of HCC with reduction in angiogenesis-related cytokines after SGLT2i treatment.

Current status and perspectives for computer-aided ultrasonic diagnosis of liver lesions using deep learning technology

An ultrasound (US) examination is a common noninvasive technique widely applied for diagnosis of a variety of diseases. Based on the rapid development of US equipment, many US images have been accumulated and are now available and ready for the preparation of a database for the development of computer-aided US diagnosis with deep learning technology. On the contrary, because of the unique characteristics of the US image, there could be some issues that need to be resolved for the establishment of computer-aided diagnosis (CAD) system in this field. For example, compared to the other modalities, the quality of a US image is, currently, highly operator dependent; the conditions of examination should also directly affect the quality of US images. So far, these factors have hampered the application of deep learning-based technology in the field of US diagnosis. However, the development of CAD and US technologies will contribute to an increase in diagnostic quality, facilitate the development of remote medicine, and reduce the costs in the national health care through the early diagnosis of diseases. From this point of view, it may have a large enough potential to induce a paradigm shift in the field of US imaging and diagnosis of liver diseases.

Liver damage related to immune checkpoint inhibitors

Recently, immune checkpoint inhibitors are becoming one of the key agents of systemic treatment of cancer. The anti-cancer mechanism of this type of agent is totally different from that of conventional therapies; blockade of regulatory receptors and ligand of immune checkpoint molecules arose anti-tumor immunity with durable response. However, owing to its unique action to host immune system, immune checkpoint inhibitors sometimes induce immune-related adverse events (irAEs) which has not been observed for conventional chemotherapies. It has been reported that irAEs are manageable by discontinuation of immune checkpoint inhibitors and corticosteroid. However, severe irAEs might lead to the unsuccessful management of cancer treatment. It is conceivable that irAEs during the treatment of immune checkpoint blockade might mimic the autoimmune disease of the specific organ, such as autoimmune hepatitis (AIH). However, detail of the pathogenesis of irAEs has not been well estimated. In this review, we specially focused on this important issue and discussed the liver toxicity of this type of agent in the context of comparison of clinical and pathological findings of liver damage related to irAEs and AIH.

Molecular Scoring of Hepatocellular Carcinoma for Predicting Metastatic Recurrence and Requirements of Systemic Chemotherapy

Hepatocellular carcinoma (HCC) causes one of the most frequent cancer-related deaths; an HCC subset shows rapid progression that affects survival. We clarify molecular features of aggressive HCC, and establish a molecular scoring system that predicts metastasis after curative treatment. In total, 125 HCCs were examined for TP53, CTNNB1, and TERT promoter mutation, methylation of 8 tumor suppressor genes, and 3 repetitive DNA sequences to estimate promoter hypermethylation and global hypomethylation. A fractional allelic loss (FAL) was calculated to represent chromosomal instability through microsatellite analysis. Molecular subclasses were determined using corresponding and hierarchical clustering analyses. Next, twenty-five HCC patients who underwent liver transplantation were analyzed for associations between molecular characteristics and metastatic recurrence; survival analyses were validated using a publicly available dataset of 376 HCC cases from the Cancer Genome Atlas (TCGA). An HCC subtype characterized by TP53 mutation, high FAL, and global hypomethylation was associated with aggressive tumor characteristics, like vascular invasion; CTNNB1 mutation was a feature of the less-progressive phenotype. A number of molecular risk factors, including TP53 mutation, high FAL, significant global hypomethylation, and absence of CTNNB1 mutation, were noted to predict shorter recurrence-free survival in patients who underwent liver transplantation (p = 0.0090 by log-rank test). These findings were validated in a cohort of resected HCC cases from TCGA (p = 0.0076). We concluded that molecular risks determined by common genetic and epigenetic alterations could predict metastatic recurrence after curative treatments, and could be a marker for considering systemic therapy for HCC patients.