Toward personalized medicine for intrahepatic cholangiocarcinoma: Pharmacogenomic stratification of patients

ADAR1 promotes cisplatin resistance in intrahepatic cholangiocarcinoma by regulating BRCA2 expression through A-to-I editing manner

Aberrant A-to-I RNA editing, mediated by ADAR1 has been found to be associated with increased tumourigenesis and the development of chemotherapy resistance in various types of cancer. Intrahepatic cholangiocarcinoma (iCCA) is a highly aggressive malignancy with a poor prognosis, and overcoming chemotherapy resistance poses a significant clinical challenge. This study aimed to clarify the roles of ADAR1 in tumour resistance to cisplatin in iCCA. We discovered that ADAR1 expression is elevated in iCCA patients, particularly in those resistant to cisplatin, and associated with poor clinical outcomes. Downregulation of ADAR1 can increase the sensitivity of iCCA cells to cisplatin treatment, whereas its overexpression has the inverse effect. By integrating RNA sequencing and Sanger sequencing, we identified BRCA2, a critical DNA damage repair gene, as a downstream target of ADAR1 in iCCA. ADAR1 mediates the A-to-I editing in BRCA2 3'UTR, inhibiting miR-3157-5p binding, consequently increasing BRCA2 mRNA and protein levels. Furthermore, ADAR1 enhances cellular DNA damage repair ability and facilitates cisplatin resistance in iCCA cells. Combining ADAR1 targeting with cisplatin treatment markedly enhances the anticancer efficacy of cisplatin. In conclusion, ADAR1 promotes tumour progression and cisplatin resistance of iCCA. ADAR1 targeting could inform the development of innovative combination therapies for iCCA.

A New Prognostic Model Covering All Stages of Intrahepatic Cholangiocarcinoma

BACKGROUND AND AIMS

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary hepatic malignancy that causes a poor survival. We aimed to identify its prognostic factors and to develop a nomogram that will predict survival of ICC patients among all stages.

METHODS

A total of 442 patients with pathology-proven ICC registered at the Fifth Medical Center of PLA General Hospital between July 2007 and December 2019 were enrolled. Subjects were followed for survival status until June 30, 2020. A prognostic model visualized as a nomogram was constructed in the training cohort using multivariate cox model, and was then validated in the validation cohort.

RESULTS

The median age was 55 years. With a median follow-up of 50.4 months, 337 patients died. The median survival was 11.6 months, with 1-, 3- and 5-year survival rates of 48.3%, 22.7% and 16.2%, respectively. Factors associated with overall survival were multiple tumors, lymph node involvement, vascular invasion, distant metastasis, decreased albumin, elevated lactate dehydrogenase (LDH), decreased iron, elevated fibrinogen, elevated CA125 and elevated CA19-9. A nomogram predicting survival of ICC patients at the time of diagnosis achieved a Harrel's c-statistic of 0.758, significantly higher than the 0.582 of the TNM stage alone. Predicted median survivals of those within the low, mid and high-risk subgroups were 35.6, 12.1 and 6.2 months, respectively.

CONCLUSIONS

A nomogram based on imaging data and serum biomarkers at diagnosis showed good ability to predict survival in patients with all stages of ICC. Further studies are needed to validate the prognostic capability of our new model.

Predictive value of the albumin-bilirubin grade on long-term outcomes of CT-guided percutaneous microwave ablation in intrahepatic cholangiocarcinoma

PURPOSE

To assess the efficacy of the albumin-bilirubin (ALBI) grade on assessing long-term outcomes of computed tomography (CT)-guided percutaneous microwave ablation (CT-PMWA) in the treatment of patients with intrahepatic cholangiocarcinoma (ICC).

METHODS

Between April 2011 and March 2018, 78 patients who underwent CT-PMWA were enrolled in this study. Overall survival (OS) and recurrence-free survival (RFS) were compared in the groups stratified by the ALBI grade and Child-Pugh score. Cox proportional hazard regression analyses were performed to determine independent predictors of OS and RFS.

RESULTS

After a median follow-up of 22.7 months (range 1-86.7 months), 67 patients had died. The cumulative 1-, 3-, and 5-year OS rates were 89.5%, 52.2%, and 35.0%, respectively. Stratified by the ALBI grade, the cumulative 1-, 3-, and 5-year OS rates were 100%, 69.2%, and 25.6% for patients with the grade 1, respectively. For patients with the ALBI grade 2, the cumulative 1-, 3-, and 5-year OS rates were 41.0%, 10.3%, and 10.3%, respectively. Patients with a hepatic function of the ALBI grade 1 had significantly higher OS rates than patients with the ALBI grade 2 (p < .001). The multivariate analysis showed tumor size (Hazard Ratio[HR] 95% Confidence Interval[CI]:9.03[1.01-80.52], p = .049) and the ALBI grade (HR[95%CI]:9.56[1.58-58.00], p = .014) were associated with OS, and tumor size (HR: 2.03[0.69-8.04], p = .049) was associated with RFS.

CONCLUSIONS

The preliminary data of this study showed the ALBI grade was effective to predict long-term outcomes of CT-PMWA in ICCs. Further study is necessary to validate our results by a large, multi-center patient cohort.