The Genomic Landscape and Its Clinical Implications in Hepatocellular Carcinoma

Activated TAZ induces liver cancer in collaboration with EGFR/HER2 signaling pathways

Background

Liver cancer is a major global health concern due to the steady increases in its incidence and mortality. Transcription factors, yes-associated protein (YAP) and WW domain-containing transcription regulator protein 1 (WWTR1, also known as TAZ) have emerged as critical regulators in human hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC), the two major types of primary liver cancer. However, our study as well as other previous reports have shown that activation of YAP and TAZ (YAP/TAZ) in adult murine livers is insufficient for the development of liver cancer, suggesting a requirement for an additional oncogenic collaborator for liver carcinogenesis in adulthood. Therefore, we sought to identify the oncogenic partners of YAP/TAZ that promote hepatocarcinogenesis in adults.

Methods

Data analysis of the transcriptome of patients with liver cancer was performed using the national center for biotechnology information (NCBI) gene expression omnibus (GEO) database and the cancer genome atlas (TCGA). The cancer therapeutics response portal (CTRP) was used to investigate the correlation between sensitivity to chemicals and the copy number of TAZ in human cancer cell lines. Transposons encoding constitutively activated forms of TAZ (TAZ^S89A), BRAF (BRAF^V600E), and PIK3CA (PI3K^E545K) were used for hydrodynamic tail vein injection. Mice were monitored at least twice per week and sacrificed when moribund. Tumor-bearing livers were formalin fixed for hematoxylin–eosin staining and immunohistochemistry.

Results

Through database analyses, we identified EGFR/HER2 signaling to be essential in human cancers with high TAZ activity. Furthermore, immunohistochemical analyses showed that human HCC and CC tissues with high YAP/TAZ activities exhibited concomitant activation of EGFR/HER2 signaling pathways. To demonstrate that EGFR/HER2 signaling promotes YAP/TAZ-mediated hepatocarcinogenesis, TAZ^S89A was simultaneously expressed in murine adult livers with BRAF^V600E or PI3K^E545K, activated forms of effector molecules downstream of EGFR/HER2 signaling pathways. Expression of TAZ^S89A plus BRAF^V600E induced HCC, whereas TAZ^S89A and PI3K^E545K led to the development of CC-like cancer.

Conclusions

Our study demonstrates that TAZ collaborates with EGFR/HER2 signaling pathways to induce both HCC and CC.

Supplementary information

The online version contains supplementary material available at 10.1186/s12885-022-09516-1.

Comprehensive clinicopathologic study of alpha fetoprotein-expression in a large cohort of patients with hepatocellular carcinoma

Alpha fetoprotein (AFP) is the most widely used diagnostic and prognostic serum biomarker for hepatocellular carcinoma (HCC). Despite its wide clinical use, a systematic clinicopathologic study comparing AFP expression in HCC in situ with serum AFP concentrations has not yet been conducted. To analyze AFP expression in a large cohort of patients by immunohistochemistry, we employed a comprehensive tissue microarray with 871 different HCCs of overall 561 patients. AFP immunoreactivity was detected in only about 20% of HCC core biopsies, whereas 48.9% of the patients displayed increased serum values (>12 ng/mL). Immunostaining of whole tumor slides revealed that lack of detectable immunoreactivity in core biopsies in a subgroup of patients with elevated AFP serum concentrations is due to heterogeneous intratumoral AFP expression. Serum AFP concentrations and AFP expression in situ were moderately correlated (Spearman's rank correlation coefficient .53, P = 1.2e - 13). High AFP expression detected in serum (>227.3 ng/mL) or in situ predicted unfavorable prognosis and was associated with vascular invasion, higher tumor grade and macrotrabecular-massive tumor subtype. Multivariate and ROC curve analysis demonstrated that high AFP concentrations in serum is an independent prognostic parameter and represents the more robust prognostic predictor in comparison to AFP immunostaining of core biopsies. The previously published vessels encapsulating tumor clusters (VETC) pattern turned out as an additional, statistically independent prognostic parameter. AFP-positivity was associated with increased tumor cell apoptosis, but not with increased vascular densities. Additionally, AFP-positive tumors displayed increased proliferation rates, urea cycle dysregulation and signs of genomic instability, which may constitute the basis for their increased aggressiveness.

Infiltrative hepatocellular carcinoma with multiple lung metastasis completely cured using nivolumab: a case report

The current Food and Drug Administration-approved systemic treatments for advanced hepatocellular carcinoma (HCC) include multikinase inhibitors (tyrosine kinase inhibitor [TKI]) and immune checkpoint inhibitors (ICIs). Among ICIs, nivolumab is used as second-line therapy for advanced HCC after sorafenib failure or patient intolerance. In this case, a patient with infiltrative HCC and portal vein tumor thrombosis was treated with hepatic arterial infusion chemotherapy (HAIC) and radiation therapy. New lung metastasis developed after HAICs; thus, lenvatinib treatment was initiated. However, the disease progressed. Thereafter, sorafenib treatment was initiated but he developed intolerance, with grade 3 sorafenib-related diarrhea. Subsequently, nivolumab was administered as rescue therapy. He demonstrated a partial response to nivolumab after the third treatment and viable HCCs in the lungs and liver completely disappeared after the 24th treatment. These findings suggest that nivolumab could be used as an effective rescue therapy for advanced HCC progression after TKI treatment.

Update on Hepatocellular Carcinoma: a Brief Review from Pathologist Standpoint

Hepatocellular carcinoma is one of the most common cancers and an important health problem all over the world. Its prognosis is poor. For better patient care, early diagnosis is essential. Although new imaging techniques have a big impact on hepatocellular carcinoma diagnosis, histopathological examination is still the gold standard for precise diagnosis. Histopathological evaluation gives exact diagnosis in the meaning of tumor size, histological subtypes, grading, and differential diagnosis from metastasis and other tumors. Immunohistochemistry as a part of diagnostic histopathological technique plays an important role in routine practice. Immunohistochemistry is useful for confirming of hepatocytic origin, supporting hepatocellular malignancy, and differential diagnosis. It also gives prognostic information. There are growing attempts to classify tumors by their molecular genetic signatures. This is also actual for hepatocellular carcinoma. This mini review focuses on the histopathology of hepatocellular carcinoma including subtypes; differential diagnosis and immunohistochemistry as an ancillary diagnostic tool, updated or added entities, i.e., combined hepatocellular-cholangiocarcinoma; small hepatocellular carcinoma; correlation with molecular studies; and future perspectives.

Tumor aggressiveness is independent of radiation quality in murine hepatocellular carcinoma and mammary tumor models

PURPOSE

Estimating cancer risk associated with interplanetary space travel is complicated. Human exposure data to high atomic number, high-energy (HZE) radiation is lacking, so data from low linear energy transfer (low-LET) γ-ray radiation is used in risk models, with the assumption that HZE and γ-ray radiation have comparable biological effects. This assumption has been challenged by reports indicating that HZE radiation might produce more aggressive tumors. The goal of this research is to test whether high-LET HZE radiation induced tumors are more aggressive.

MATERIALS AND METHODS

Murine models of mammary and liver cancer were used to compare the impact of exposure to 0.2Gy of 300MeV/n silicon ions, 3 Gy of γ-rays or no radiation. Numerous measures of tumor aggressiveness were assessed.

RESULTS

For the mammary cancer models, there was no significant change in the tumor latency or metastasis in silicon-irradiated mice compared to controls. For the liver cancer models, we observed an increase in tumor incidence but not tumor aggressiveness in irradiated mice.

CONCLUSION

Tumors in the HZE-irradiated mice were not more aggressive than those arising from exposure to low-LET γ-rays or spontaneously. Thus, enhanced aggressiveness does not appear to be a uniform characteristic of all tumors in HZE-irradiated animals.

[Hepatocellular carcinoma: new provisions of the WHO classification, 5th edition, 2019]

The WHO Classification of Digestive System Tumors (WHO, 5th Edition, 2019) presents new provisions on the morphological, molecular genetic, and therapeutic aspects of hepatocellular carcinoma (HCC). This classification versus the 2010 edition underwent substantial changes. Undifferentiated carcinoma (ICD-0: 8020/3) was excluded. The TNM staging system introduces additional gradations. Based on new evidence, HCC types and subtypes (scirrhous, clear cell, steatohepatic, and others) were identified depending on gene mutations according to ICD-11. The classification changes are of not only important theoretical, but also applied significance. These are valuable for oncologists and pathologists.