Biomarkers of intrahepatic cholangiocarcinoma: diagnosis and response to therapy

Application of machine learning models to explore prognosis and cause of death in advanced intrahepatic cholangiocarcinoma patients undergoing chemotherapy

BACKGROUND

This study was aimed at examining the causes of death (CODs) in patients with advanced intrahepatic cholangiocarcinoma (ICC) undergoing chemotherapy (CT). In addition, machine learning models were incorporated to predict the treatment outcomes of patients with advanced ICC and identify the factors most closely related to prognosis.

METHODS

A total of 5564 patients (CT group, 3632; non-CT group, 1932) were included in the Surveillance Epidemiology and End Results registries between 2000 and 2020. The CODs were compared between the two groups before and after the inverse probability of treatment weighting (IPTW). Furthermore, seven machine learning models were utilized as predictive tools to select variable features, aiming to assess the therapeutic effectiveness in patients with advanced ICC.

RESULTS

After IPTW, the CT group exhibited a lower cumulative incidence of cholangiocarcinoma-related deaths (30%, 49%, and 73% vs. 59%, 66%, and 73%; P < 0.001), secondary malignant neoplasms (8.5%, 13%, and 20% vs. 19%, 22%, and 24%; P < 0.001), and other CODs (1.8%, 2.9%, and 4.4% vs. 4.1%, 4.6%, and 5.4%; P < 0.001) at 0.5-, 1-, and 3- years than the non-CT group, whereas the cumulative incidence of cardiovascular diseases (P = 0.4) was comparable between the two groups. Of the seven machine learning models, the random forest model showed the highest predictive effectiveness. This model verified that variables such as CT, radiotherapy, tumor dimensions, sex, and distant metastasis were strongly correlated with the prognosis of advanced ICC.

CONCLUSIONS

CT has improved the therapeutic efficacy of advanced ICC without significantly increasing other CODs. Furthermore, the analysis of various features using machine learning models has confirmed that the random forest model demonstrates the highest predictive performance.

Biomarkers for the Evaluation of Immunotherapy in Patients with Cholangiocarcinoma

Cholangiocarcinoma is a rare primary liver cancer with poor prognosis, due to the advanced stage at the time of diagnosis and limited therapeutic options, with poor response. Chemotherapy remains the standard first-line treatment, but the advent of immunotherapy has recently induced promising results. Given the fact that diagnosis frequency is increasing nowadays and the survival rate remains very low, it is crucial to recognize patients who are suitable for immunotherapy and will have the best response. Different types of biomarkers, such as interleukins, exosomes, mi-RNA, ctDNA, and gene mutations, have been studied for their feasibility, not only for the early diagnosis of biliary tract cancer but also for the determination of responsiveness in treatment. Less frequently, these studies focus on finding and observing biomarkers in patients who receive immunotherapy. This review aims to summarize current knowledge of existing/promising biomarkers in patients with unresectable or metastatic cholangiocarcinoma, treated with immunotherapy as monotherapy, or combined with chemotherapy.

Cystatin B Promotes the Proliferation, Migration, and Invasion of Intrahepatic Cholangiocarcinoma

Background and Aims: Cystatin B (CSTB) has been demonstrated to play a significant role in the pathogenesis of a number of diseases, including the evolution and progression of multiple cancers. Nevertheless, the function of CSTB in intrahepatic cholangiocarcinoma (iCCA) is yet to be fully elucidated. Methods: By analyzing transcriptome sequencing data from the FU-iCCA cohort, the iCCA-27 cohort, and three public databases, we identified genes associated with iCCA prognosis and selected CSTB as the subject of our study. The expression of CSTB was examined between tumor tissues and adjacent normal tissues obtained from iCCA patients via Western blot analysis. The clinical significance of CSTB was analyzed through immunohistochemical staining of a tissue microarray. Subsequently, the biological effects of CSTB overexpression or knockdown on iCCA cells were evaluated in vitro and in vivo. Results: CSTB expression was markedly elevated in the CCA pathological tissues in comparison to the corresponding adjacent normal tissues. A correlation was identified between higher CSTB expression and poorer patient prognosis in the analysis of 176 iCCA patients. It is noteworthy that overexpression or knockdown experiments demonstrated that CSTB plays a role in the proliferation, migration, and invasion of cells. In subcutaneous tumor models in nude mice, the knockdown of CSTB resulted in smaller tumors in terms of size and weight, and a slower growth rate. Conclusions: CSTB plays a significant function in the regulation of iCCA progression and may serve as a promising biomarker for iCCA.

[18F]FDG PET/CT versus [18F]FDG PET/MRI in the evaluation of liver metastasis in patients with primary cancer: A head-to-head comparative meta-analysis

PURPOSE

This meta-analysis aimed to compare the diagnostic effectiveness of [18F]FDG PET/CT with that of [18F]FDG PET/MRI in terms of identifying liver metastasis in patients with primary cancer.

METHODS

PubMed, Embase, Web of Science, and the Cochrane Library were searched, and studies evaluating the diagnostic efficacy of [18F]FDG PET/CT and [18F]FDG PET/MRI in patients with liver metastasis of primary cancer were included. We used a random effects model to analyze their sensitivity and specificity. Subgroup analyses and corresponding meta-regressions focusing on race, image analysis, study design, and analysis methodologies were conducted. Cochrane Q and I2 statistics were used to assess intra-group and inter-group heterogeneity.

RESULTS

Seven articles with 343 patients were included in this meta-analysis. The sensitivity of [18F]FDG PET/CT was 0.82 (95 % CI: 0.63-0.96), and that of [18F]FDG PET/MRI was 0.91 (95 % CI: 0.82-0.98); there was no significant difference between the two methods (P = 0.32). Similarly, both methods showed equal specificity: 1.00 (95 % CI: 0.95-1.00) for [18F]FDG PET/CT and 1.00 (95 % CI: 0.96-1.00) for [18F]FDG PET/MRI, and thus, there was no significant difference between the methods (P = 0.41). Furthermore, the subgroup analyses revealed no differences. Meta-regression analysis revealed that race was a potential source of heterogeneity for [18F]FDG PET/CT (P = 0.01), while image analysis and contrast agent were found to be potential sources of heterogeneity for [18F]FDG PET/MRI (P = 0.02).

CONCLUSIONS

[18F]FDG PET/MRI has similar sensitivity and specificity to [18F]FDG PET/CT for detecting liver metastasis of primary cancer in both the general population and in subgroups. [18F]FDG PET/CT may be a more cost-effective option. However, the conclusions of this meta-analysis are tentative due to the limited number of studies included, and further research is necessary for validation.

Downregulation of JAM3 occurs in cholangiocarcinoma by hypermethylation: A potential molecular marker for diagnosis and prognosis

Junctional adhesion molecular 3 (JAM3) is downregulated by hypermethylation in cancers but is unclear in cholangiocarcinoma. The JAM3 expression level was checked in cholangiocarcinoma cell lines and tissues. Methylated JAM3 was detected in cell lines, tissues and plasma cell-free DNAs (cfDNA). The roles of JAM3 in cholangiocarcinoma were studied by transfection of siRNA and pCMV3-JAM3. The survival analysis was based on the Gene Set Cancer Analysis (GSCA) database. JAM3 was downregulated in HCCC-9810 and HuCCT1 cell lines and tissues by hypermethylation. Methylated JAM3 was detected in cfDNAs with 53.3% sensitivity and 96.6% specificity. Transfection of pCMV3-JAM3 into HCCC-9810 and HuCCT1 induced apoptosis and suppressed cell proliferation, migration and invasion. The depletion of JAM3 in RBE cells using siRNA decreased apoptosis and increased cell proliferation, migration and invasion. Hypermethylation of JAM3 was associated with tumour differentiation, metastasis and TNM stage. Downregulation and hypermethylation of JAM3 were related to poor progression-free survival. Junctional adhesion molecular 3 may function as a tumour suppressor in cholangiocarcinoma. Methylated JAM3 DNA may represent a non-invasive molecular marker for the early detection of cholangiocarcinoma and prognosis.

Tumor size and survival in intrahepatic cholangiocarcinoma treated with surgical resection or ablation

OBJECTIVES

We performed a retrospective analysis within a national cancer registry on outcomes following resection or ablation for intrahepatic cholangiocarcinoma (iCCA).

METHODS

The National Cancer Database was queried for patients with clinical stage I-III iCCA diagnosed during 2010-2018, who underwent resection or ablation. Overall survival (OS) was compared with Kaplan-Meier and multivariable Cox proportional hazards methods.

RESULTS

Of 2140 patients, 1877 (87.7%) underwent resection and 263 (12.3%) underwent ablation, with median tumor sizes of 5.5 and 3 cm, respectively. Overall, resection was associated with greater median OS (41.2 months (95% confidence interval [95% CI]: 37.6-46.2) vs. 28 months (95% CI: 15.9-28.6) on univariable analysis (p < 0.0001). There was no significant difference on multivariable analysis (p = 0.42); however, there was a significant interaction between tumor size and management. On subgroup analysis of patients with tumors <3 cm, there was no difference in OS between resection versus ablation. However, ablation was associated with increased mortality for tumors ≥3 cm.

CONCLUSION

Although resection is associated with improved OS for tumors ≥3 cm, we observed no difference in survival between management strategies for tumors < 3 cm. Ablation may be an alternative therapeutic strategy for small iCCA, particularly in patients at risk for high surgical morbidity.

Contrast-Enhanced Imaging in the Management of Intrahepatic Cholangiocarcinoma: State of Art and Future Perspectives

Intrahepatic cholangiocarcinoma (iCCA) represents the second most common liver cancer after hepatocellular carcinoma, accounting for 15% of primary liver neoplasms. Its incidence and mortality rate have been rising during the last years, and total new cases are expected to increase up to 10-fold during the next two or three decades. Considering iCCA's poor prognosis and rapid spread, early diagnosis is still a crucial issue and can be very challenging due to the heterogeneity of tumor presentation at imaging exams and the need to assess a correct differential diagnosis with other liver lesions. Abdominal contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) plays an irreplaceable role in the evaluation of liver masses. iCCA's most typical imaging patterns are well-described, but atypical features are not uncommon at both CT and MRI; on the other hand, contrast-enhanced ultrasound (CEUS) has shown a great diagnostic value, with the interesting advantage of lower costs and no renal toxicity, but there is still no agreement regarding the most accurate contrastographic patterns for iCCA detection. Besides diagnostic accuracy, all these imaging techniques play a pivotal role in the choice of the therapeutic approach and eligibility for surgery, and there is an increasing interest in the specific imaging features which can predict tumor behavior or histologic subtypes. Further prognostic information may also be provided by the extraction of quantitative data through radiomic analysis, creating prognostic multi-parametric models, including clinical and serological parameters. In this review, we aim to summarize the role of contrast-enhanced imaging in the diagnosis and management of iCCA, from the actual issues in the differential diagnosis of liver masses to the newest prognostic implications.

Biomarkers for predicting the prognosis of intrahepatic cholangiocarcinoma: A retrospective single-center study

The aim of this retrospective study was to investigate the association between preoperative serological and clinical indicators and postoperative recovery in patients who had undergone resection of intrahepatic cholangiocarcinoma (ICC). We collected data form the medical records of patients who underwent operations for the treatment of ICC at Qingdao University Affiliated Hospital from 2015 to 2021. We analyzed the data to explore the independent predictors of disease prognosis after surgery for ICC. By univariate analysis, we found that the following factors were significantly associated with overall survival and tumor-free survival in patients with ICC: TNM stage; degree of vascular invasion; levels of hemoglobin, carcinoembryonic antigen, carbohydrate antigen 125, direct bilirubin, alkaline phosphatase, and albumin; prothrombin time; neutrophil to lymphocyte ratio; prothrombin time to albumin ratio; albumin to alkaline phosphatase ratio; albumin to gamma-glutamyl transferase ratio; prognostic nutrition Index, and incisional margin. However, only carbohydrate antigen 24-2 and glutamyl transpeptidase were correlated with overall survival in patients with ICC. However, only a positive history of biliary surgery was significantly associated with tumor-free survival in patients with ICC. Preoperative prothrombin time, vascular invasion, N-stage, incisal edge, and carcinoembryonic antigen levels may be simple predictors of disease progression in ICC after hepatectomy.

Development of extrahepatic bile ducts and mechanisms of tumorigenesis: Lessons from mouse models

The biliary system is a highly branched tubular network consisting of intrahepatic bile ducts (IHBDs) and extrahepatic bile ducts (EHBDs). IHBDs are derived from hepatic progenitor cells, while EHBDs originate directly from the endoderm through a separate branching morphogenetic process. Traits that are important for cancer are often found to overlap in developmental and other processes. Therefore, it has been suggested that intrahepatic cholangiocarcinomas (iCCAs) and extrahepatic cholangiocarcinomas (eCCAs) have different developmental mechanisms. While much evidence is being gathered on the mechanism of iCCAs, the evidence for eCCA is still very limited. The main reason for this is that there are very few appropriate animal models for eCCA. We can gain important insights from these animal models, particularly genetically engineered mouse models (GEMMs). GEMMs are immunocompetent and mimic human CCA subtypes with a specific mutational pattern, allowing the development of precancerous lesions, that is, biliary intraepithelial neoplasia (BilIN) and intraductal papillary neoplasm of the bile duct (IPNB). This review provides a summary of the pathogenesis and mechanisms of eCCA that can be revealed by GEMMs. Furthermore, we discuss several clinical questions, such as whether BilIN and IPNB really become malignant, whether the peribiliary gland is the origin of eCCAs, and others.

Identification of macrophage correlated biomarkers to predict the prognosis in patients with intrahepatic cholangiocarcinoma

Background

It has been shown that tumor-associated immune cells, particularly macrophages, play a fundamental role in the development and treatment response of intrahepatic cholangiocarcinoma (ICC). However, little is known about macrophages at the single cellular level of ICC patients.

Methods

ScRNA-seq from Zhang et al. was used in the present study to identify the genes differentially expressed in ICCs. Furthermore, transcriptomic data from TCGA datasets, IHC and flowcytometry from our cohort were used to confirm the findings. Kaplan-Meier and TIDE scores were also used for prognostic analysis and ICB responses.

Results

A significant number of macrophages were found in ICCs as compared to adjacent tissues. We then extracted, processed, and classified the macrophages from the ICCs and adjacent tissues into 12 clusters. Significantly, the macrophages from the ICC exhibited an immunosuppressed state in terms of both signature gene expression and functional enrichment. Furthermore, our results indicate that, of the 10 selective tumor-promoting genes of macrophages, only MMP19 and SIRPα can predict ICB responses in ICCs. Although a higher expression of MMP19 and SIRPα predict a poor prognosis for ICCs without immunotherapy after surgery, patients with high SIRPα expression were more sensitive to immunotherapy, whereas those with high MMP19 expression were not sensitive to immunotherapy. To define the mechanisms, we found that SIRPα^hi ICCs exhibited an increased enrichment KEGG pathway of leukocyte transendothelial migration and neutrophil extracellular trap formation. The increased immune cell infiltration will increase sensitivity to immunotherapy.

Conclusion

Collectively, macrophages are critical to the immune status of ICCs, and MMP19 and SIRPα can predict prognosis and ICB responses for ICCs.