[Hepatocellular carcinoma]

Targeting microRNA methylation: Innovative approaches to diagnosing and treating hepatocellular carcinoma

Hepatocellular carcinoma (HCC) stands as the most prevalent form of primary liver cancer and is frequently linked to underlying chronic liver conditions such as hepatitis B, hepatitis C, and cirrhosis. Despite the progress achieved in the field of oncology, HCC remains a significant clinical challenge, primarily due to its typically late-stage diagnosis and the complex and multifaceted nature of its tumor biology. These factors contribute to the limited effectiveness of current treatment modalities and result in poor patient prognosis. Emerging research has underscored the vital role of microRNAs (miRNAs)-small, non-coding RNA molecules that play a pivotal part in the post-transcriptional regulation of gene expression. These miRNAs are integral to a wide array of cellular functions, including proliferation, apoptosis, and differentiation, and their dysregulation is closely associated with the pathogenesis of various cancers, notably HCC. A major focus in recent studies has been on the epigenetic regulation of miRNAs through methylation, a key mechanism that modulates gene expression. This process, involving the addition of methyl groups to CpG islands in the promoter regions of miRNA genes, can result in either gene silencing or activation, influencing the expression of oncogenes and tumor suppressor genes. Such alterations have profound implications for tumor growth, metastasis, and resistance to treatment. Evidence suggests that aberrant miRNA methylation can serve as a powerful biomarker for early detection and prognosis in HCC and may present novel opportunities for therapeutic intervention. This review aims to provide a comprehensive overview of the current landscape of miRNA methylation in HCC, elucidating its significance in the molecular mechanisms of liver cancer and examining its potential for clinical application. By exploring the diagnostic and therapeutic potential of miRNA methylation, we seek to highlight its value in enhancing personalized treatment strategies and improving patient outcomes.

Liver Transplantation for Hepatocarcinoma: Results over Two Decades of a Transplantation Programme and Analysis of Factors Associated with Recurrence

BACKGROUND

In recent years, many studies have attempted to develop models to predict the recurrence of hepatocarcinoma after liver transplantation.

METHOD

A single-centre, retrospective cohort study analysed patients receiving transplants due to hepatocarcinoma during the 20 years of the transplant programme. We analysed patient survival, hepatocarcinoma recurrence and the influence of the different factors described in the literature as related to hepatocarcinoma recurrence. We compared the results of previous items between the first and second decades of the transplantation programme (1995-2010 and 2010-2020).

RESULTS

Of 265 patients, the patient survival rate was 68% at 5 years, 58% at 10 years, 45% at 15 years and 34% at 20 years. The overall recurrence rate of hepatocarcinoma was 14.5%, without differences between periods. Of these, 54% of recurrences occurred early, in the first two years after transplantation. Of the parameters analysed, an alpha-fetoprotein level of >16 ng/mL, the type of immunosuppression used and the characteristics of the pathological anatomy of the explant were significant. A trend towards statistical significance was identified for the number of nodules and the size of the largest nodule. Logistic regression analysis was used to develop a model with a sensitivity of 85.7% and a specificity of 35.7% to predict recurrences in our cohort. Regarding the comparison between periods, the survival and recurrence rates of hepatocarcinoma were similar. The impact of the factors analysed in both decades was similar.

CONCLUSIONS

Most recurrences occur during the first two years post-transplantation, so closer follow-ups should be performed during this period, especially in those patients where the model predicts a high risk of recurrence. The detection of patients at higher risk of recurrence allows for closer follow-up and may, in the future, make them candidates for adjuvant or neoadjuvant systemic therapies to transplantation.

LncRNA XXYLT1-AS2 promotes tumor progression via autophagy inhibition through ubiquitinated degradation of TFEB in hepatocellular carcinoma

PURPOSE

There is compelling evidence that long-stranded non-coding RNAs (lncRNAs) play an important role in the progression of hepatocellular carcinoma (HCC). The aim of this study was to investigate the role of lncRNA XXYLT1 antisense-2 (XXYLT1-AS2) in HCC progression.

METHODS

Real-time PCR was used to assess the levels of XXYLT1-AS2 in plasma from HCC and normal patients. Cell proliferation, apoptosis, migration, and invasion were monitored, and tumor xenografts were established to investigate the biological functions of XXYLT1-AS2 by gain-of-function and loss-of-function studies in vitro and in vivo, the expression of autophagy biomarkers and transcriptional factor EB (TFEB) was examined by immunoprecipitation, ubiquitination assays, and western blotting. Autophagy inhibitor, 3-methyladenine (3MA), and proteasome inhibitor, MG132, were used to verify the role of autophagy in HCC progression and the effect of XXYLT1-AS2 on TFEB ubiquitination, respectively.

RESULTS

In this study, we identified that lncRNA XXYLT1-AS2 is highly expressed in HCC plasma and promotes tumor growth in vivo. In functional studies, it was found that silent expression of XXYLT1-AS2 inhibited HCC proliferation, migration, invasion, and activated autophagy of HCC cells, which were attenuated by autophagy inhibitor, 3MA. Mechanistically, XXYLT1-AS2 decreased the protein level of TFEB through promoting its degradation by ubiquitin proteasome pathway.

CONCLUSION

XXYLT1-AS2 plays an oncogenic role in HCC progression through inhibition of autophagy via promoting the degradation of TFEB, and thus could be a novel target for HCC treatment.

Bariatric surgery in liver cirrhosis

Introduction

Obesity is frequently associated with its hepatic manifestation, the nonalcoholic fatty liver disease (NAFLD). The most effective treatment for morbid obesity is bariatric surgery (BS) also improving NAFLD and liver function. In patients where NAFLD has already progressed to liver cirrhosis, BS can be considered a high-risk procedure. Hence, consideration of the procedure and the most appropriate timing is crucial.

Material and Methods

Obese patients suffering from NAFLD who underwent BS from two German University Medical Centers were retrospectively analyzed.

Results

Twenty-seven patients underwent BS. Most common procedures were laparoscopic Roux-en-Y-gastric (RYGB) and laparoscopic sleeve gastrectomy (SG). All patients suffered from liver cirrhosis Child A. A preoperative transjugular portosystemic shunt (TIPS) was established in three patients and failed in another patient. Postoperative complications consisted of wound healing disorders (n = 2), anastomotic bleeding (n = 1), and leak from the staple line (n = 1). This patient suffered from intraoperatively detected macroscopic liver cirrhosis. Excess weight loss was 73% and 85% after 1 and 2 years, respectively. Two patients suffered from postoperative aggravation of their liver function, resulting in a higher Child-Pugh score, while three could be removed from the waiting list for a liver transplantation.

Conclusion

BS leads to weight loss, both after SG and RYGB, and potential improvement of liver function in liver cirrhosis. These patients need to be considered with care when evaluated for BS. Preoperative TIPS implantation may reduce the perioperative risk in selected patients.