Highly-sensitive identification of alpha-fetoprotein mRNA in circulating peripheral blood of hepatocellular carcinoma patients

Combined identification of three lncRNAs in serum as effective diagnostic and prognostic biomarkers for hepatitis B virus-related hepatocellular carcinoma

Hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC) is a common, highly invasive malignant tumor associated with a high mortality rate. This study aimed to identify the effective diagnostic and prognostic biomarkers for HBV-related HCC. With HBV-related HCC RNA-sequencing data of The Cancer Genome Atlas (TCGA) database, 159 differentially expressed long non-coding RNAs (lncRNAs) between HBV-related HCC and para-carcinoma normal samples were identified, and 12 lncRNAs were eventually assessed for deeper research. Classification analysis developed a three-lncRNA signature of AC005332.5, ELF3-AS1, and LINC00665, which was demonstrated to be the most discriminatory with an AUC (Area Under the Curve) value of 0.913 (95% CI: 0.8610-0.9665) and verified in validation patients. The expression levels of AC005332.5, ELF3-AS1, and LINC00665 were significantly changed with different tumor stages or grades. Survival analysis revealed that AC005332.5, ELF3-AS1, and LINC00665 were highly associated with the prognosis of overall survival. Additionally, the lncRNA signature yielded statistical significance to predict clinical outcomes independently from other clinical variables in validation patients, as suggested in the multivariate Cox hazards analysis. Conclusively, a three-lncRNA signature of AC005332.5, ELF3-AS1, and LINC00665 may serve as an excellent diagnostic biomarker for HBV-related HCC and potential prognostic significance for HBV-related HCC sufferers. This article is protected by copyright. All rights reserved.

Clinical applications of liquid biopsy as prognostic and predictive biomarkers in hepatocellular carcinoma: circulating tumor cells and circulating tumor DNA

Hepatocellular carcinoma (HCC) is a highly malignant disease with a poor prognosis and high mortality due to a low early diagnosis rate, resistance to systemic treatments and progression to late-stage liver disease. Owing to limitations in the detection of HCC and the lack of awareness of healthcare systems, fewer than 40% of HCC patients are eligible for surgery due to advanced stages of the disease at the time of diagnosis and the occurrence of multiple lesions in the cirrhotic or fibrotic liver. At present, the updated American Association for the Study of Liver Disease (AASLD) guidelines no longer recommend alpha-fetoprotein (AFP) testing as a part of diagnostic evaluation. Thus, it is imperative to establish a novel diagnostic strategy with high sensitivity and reliability to monitor risk factors to detect HCC at an early stage. In recent years, “liquid biopsy,” (including circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA)), has emerged as a technique for the characterization of circulating cells, providing a strong basis for the individualized treatment of patients. As a noninvasive detection method, liquid biopsy is expected to play an important role in the early diagnosis, dynamic monitoring of cancer patients and drug screening. In this review, we will focus on the clinical applications, recent studies and future prospects of liquid biopsy, particularly focusing on HCC.

New Developments in Orthotopic Liver Transplant for Hepatocellular Carcinoma

The use of orthotopic liver transplant for hepatocellular carcinoma was a major advance, pioneered by Thomas E. Starzl as a way to circumvent the limitations imposed on the liver surgeon by the presence of cirrhosis and liver failure. Patients with a few small tumors, whatever their degree of liver damage, may expect prolonged survival (70% at 5 years). Patients with more advanced tumors have high recurrence rates and more limited survival, possibly due to immune suppression or pretransplant understaging of their tumors. Another possibility is that patients with micrometastases have a longer survival time, during which the metastases eventually become evident. Recent advances include the identification of patients using levels of tumor markers to allow more careful patient selection with better outcomes. The contributions of molecular signatures and the new, effective antiviral agents are possibly significant.

Circulating cell-free nucleic acids: promising biomarkers of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is considered to be a fatal disease because of its late diagnosis, underlying liver disease, and refractoriness to systemic treatments. Biomarkers with high sensitivity and specificity that are minimally invasive, reproducible, and easily available have important clinical utility for early diagnosis, prognostication, and pharmacodynamics evaluation. Until now, most of the circulating HCC biomarkers used in clinical practice were protein molecules. However, these biomarkers often had low sensitivity and specificity. In the past decade, circulating cell-free nucleic acids (cfNAs) have been extensively studied. We review the studies that evaluated cfNAs as circulating HCC biomarkers and discuss recent advances with regard to their diagnostic and prognostic significance.

Diagnosing and monitoring hepatocellular carcinoma with alpha-fetoprotein: new aspects and applications

Hepatocellular carcinoma is the 5th most common cancer in the world. Prognosis for this disease is poor since hepatocellular carcinoma is mostly diagnosed at an advanced stage. Serum alpha-fetoprotein (AFP) is one of the most common diagnostic markers for hepatocellular carcinoma. However, its diagnostic value is more and more questioned. Therefore, research has focussed on AFP related parameters (AFP mRNA and AFP glycoforms). The aim of this paper is to review the present knowledge on AFP and its related parameters in diagnosing and monitoring HCC. AFP related parameters can be arranged in two types: AFP mRNA and AFP glycoforms. AFP mRNA is a potentially prognostic marker and AFP mRNA assays are based on PCR techniques. The AFP glycoforms have diagnostic potential and assays are based on isoelectric focussing and lectin affinity electrophoretic methods. Up to now the diagnostic use of the AFP related parameters is limited. Although some of them are recommended as a complementary test, they cannot (yet) replace serum AFP as the golden standard of diagnostic markers for hepatocellular carcinoma.

Clinicopathologic features of poorly differentiated hepatocellular carcinoma

BACKGROUND AND OBJECTIVES

Clinicopathologic features of poorly differentiated hepatocellular carcinoma (HCC) have not been elucidated. The purpose of this study was to clarify the characteristics of poorly differentiated HCC in hepatectomized patients.

METHODS

From 1986 to 2001, 354 HCC patients underwent curative hepatectomy in our institution and were prospectively followed. Histological examinations revealed 43 well-differentiated HCC tumors, 273 moderately differentiated HCC tumors, and 38 poorly differentiated HCC tumors. Clinicopathologic factors and outcomes after hepatectomy were compared statistically.

RESULTS

Only serum alpha-fetoprotein level was significantly different in the poorly differentiated HCC group from that in the moderately differentiated HCC group preoperatively (P=0.0001). Although there were no significant differences between overall survival rates or between disease-free survival rates in the three groups, distant metastasis within 2 years after hepatectomy occurred more frequently in the poorly differentiated HCC group (21%) than in the well-differentiated HCC group (2%) (P=0.011) or moderately differentiated HCC group (8%) (P=0.018). Distant metastasis occurred in about 40% of patients in the poorly differentiated HCC group with tumor size greater than 3 cm.

CONCLUSIONS

Poorly differentiated HCC tumors larger than 3 cm are already of advanced stage representing distant metastasis in the early period after hepatectomy.

Prospective evaluation of circulating hepatocytes by alpha-fetoprotein messenger RNA in patients with hepatocellular carcinoma

BACKGROUND

The significance of alpha-fetoprotein (AFP) messenger RNA as a surrogate marker for isolated tumor cells in the blood of patients with hepatocellular carcinoma (HCC) is controversial. Our goals were to correlate AFP mRNA with tumor recurrence and overall survival after patients with HCC received curative operations and to analyze AFP mRNA findings in control patients.

METHODS

In this prospective controlled study, RNA was purified from the blood of 85 patients with HCC before, during, and after therapy and from 116 control patients. Complementary DNA synthesis by reverse transcriptase and polymerase chain reaction amplification was performed with primers specifically for the AFP gene. Patients with HCC were divided into 4 subgroups depending on the therapy performed: (1) orthotopic liver transplantation (OLT), (2) resection, (3) transarterial chemoembolization, and (4) no therapy.

RESULTS

AFP mRNA was detected in 28% of the patients with HCC and 3% of the control patients (P <.01) before therapy. Of patients with HCC and OLT, 2 of the 6 patients who were AFP mRNA positive had a recurrence; none of the 4 patients who were negative had a recurrence. In the HCC patients who underwent tumor resection or received no therapy, the survival rates did not differ between patients who were AFP mRNA positive and negative (P =.21 and P =.94, respectively). After the tumor resection, no difference in survival at 2 years was evident in patients who were AFP mRNA positive versus those who were AFP mRNA negative. In the HCC patients who had curative operations (OLT and resection) the sensitivity and specificity of this test for tumor recurrence were 73% and 53%, respectively, excluding surgical mortality. The International Union Against Cancer tumor stages in the subgroups of OLT and resection showed no differences between patients with positive and negative findings (P =.76 and P =.15, respectively). AFP mRNA results and serum AFP levels revealed no correlation (P =.45).

CONCLUSIONS

The qualitative measurement of AFP mRNA in the blood of patients with HCC is not a clinically relevant method for determining therapy and prognosis, especially if AFP mRNA is detected during the surgical procedure or any other liver manipulation.

Expression of alpha-fetoprotein and prostate-specific antigen genes in several tissues and detection of mRNAs in normal circulating blood by reverse transcriptase-polymerase chain reaction

BACKGROUND

alpha-Fetoprotein (AFP) and prostate-specific antigen (PSA) in serum are widely used as tumor markers in the evaluation of prognosis and management of patients with hepatocellular carcinoma and prostate cancer, respectively. To establish the molecular diagnosis of cancer, reverse transcriptase polymerase chain reaction (RT-PCR) for AFP and PSA was used to identify circulating cancer cells in the blood of cancer patients. Here, we examined the tissue-specificity of AFP and PSA and tested whether AFP and PSA are suitable targets in the detection of certain cancer cells by RT-PCR using peripheral blood samples.

METHODS

Tissue specificity of AFP and PSA was analyzed by Northern blotting and RT-PCR. Probes for AFP and PSA were hybridized with poly A+ RNAs from 50 human tissues. RT-PCR for AFP and PSA mRNA was performed using several cancerous tissues and normal tissues and peripheral blood cells from seven healthy volunteers.

RESULTS

Broad expression of AFP was observed in several tissues and a large amount of AFP mRNA was found in fetal liver. PSA was expressed in prostate, salivary gland, pancreas and uterus. By RT-PCR, AFP and PSA mRNA were detected in several tumors, including salivary pleomorphic adenoma, hilar bile duct carcinoma, pancreatic carcinoma, transitional cell carcinoma of urinary bladder and thyroid papillary carcinoma. Furthermore, AFP and PSA mRNAs were frequently detected by RT-PCR, even in peripheral blood cells from healthy volunteers.

CONCLUSIONS

Neither AFP nor PSA showed tissue-specific expression. AFP and PSA mRNA were detected in several diseased and non-diseased tissues and normal circulating blood by RT-PCR.

Quantitative analysis of alpha-fetoprotein mRNA in circulating peripheral blood of patients with hepatocellular and alpha-fetoprotein-producing gastric carcinomas

In conjunction with strategies introduced in recent years to identify cancer micrometastasis through amplification of cancer-associated mRNA, we developed a highly sensitive system to detect alpha-fetoprotein mRNA in circulating peripheral blood of hepatocellular carcinoma patients. The aim of the present study was to make our original system quantitative. Peripheral venous blood from patients with hepatocellular carcinoma and alpha-fetoprotein-producing gastric carcinoma was subjected to reverse transcription followed by our original three-step polymerase chain reaction co-amplifying both the original sequence and our synthetic competitor. We succeeded in modifying our system for quantitative analysis, and investigated the perioperative change, the postoperative change and the change after chemotherapy in order to illustrate the possible application of this method. The quantitative analysis of alpha-fetoprotein mRNA present in the peripheral blood represents a useful tool for analyzing the relationship of surgery to recurrence, the effect of chemotherapy, and to predict impending recurrence in patients with hepatocellular and alpha-fetoprotein-producing gastric carcinomas.

Cytokeratin 20 mRNA in peripheral venous blood of colorectal carcinoma patients

A highly sensitive system was previously developed by us to detect the presence of colorectal carcinoma cells in blood in the form of cytokeratin 20 (CK20) mRNA. In the present study, we used an improved version of this system to analyse the peripheral blood of 28 patients with colorectal carcinoma, five patients with non-cancerous intestinal diseases and six normal controls for the presence or absence of CK20 mRNA and to investigate the relationship between the mRNA results and prognosis. All eight patients with recurrence were positive for CK20 mRNA, as were four patients in the Dukes' C stage with either distant metastasis or dissemination. Five of the nine patients in the Dukes' C stage with neither distant metastasis nor dissemination were positive, and three of these developed recurrence within 11 months after the analysis. Only one of the seven patients in the Dukes' A or B stage was positive, and none showed recurrence during the 1-19 months of observation. None of the five patients without carcinomas or of the six normal controls was positive. Although the follow-up period is limited and the recurrences were all local at present, these results suggest that the presence of CK20 mRNA in circulation may be a useful indicator for the screening of advanced colorectal carcinoma patients with a high risk of recurrence.

Detection of colorectal carcinoma cells in circulating peripheral blood by reverse transcription-polymerase chain reaction targeting cytokeratin-20 mRNA

For the detection of circulating colorectal carcinoma cells, we investigated the presence of cytokeratin 20 (CK 20) mRNA in the peripheral blood of colorectal carcinoma patients. Application of our published technique resulted in analysis by reverse transcription followed by three-step nested polymerase chain reaction. This analysis could detect a single Colo 205 colon cancer cell mixed with 1 ml of blood. Our system also successfully detected the presence of CK 20 mRNA in actual patients' peripheral blood samples. Our highly sensitive and specific system for the detection of CK-20 mRNA from patients' peripheral blood thus seems to be useful for screening for circulating colorectal carcinoma cells.

Identification of carcinoembryonic antigen mRNA in circulating peripheral blood of pancreatic carcinoma and gastric carcinoma patients

To detect adenocarcinoma cells in the circulating peripheral blood, we "analyzed the presence of carcinoembryonic antigen (CEA) mRNA in the peripheral blood obtained from patients with pancreatic carcinoma (PC) or with gastric carcinoma (GC) and also, as controls, from pancreatitis or gastritis patients without carcinomas, a gastric lymphoma patient and four healthy volunteers. Because of the small number of carcinoma cells expected in the peripheral blood, the analysis was performed by the reverse transcription followed by an original two-step polymerase chain reaction. By this sensitive method, 3 of 9 PC patients and 2 of 9 GC patients were positive for CEA mRNA. Except for 1 highly advanced PC patient, 3 of 4 CEA mRNA-positive patients developed recurrence after curative resection or liver metastasis after palliative operation within 9 months after the analysis. None of the control patients was positive for CEA mRNA in the peripheral blood. The results suggest that our sensitive RT-PCR method for detecting CEA mRNA in the peripheral blood is practically useful to find the hematogenous spreading of adenocarcinoma cells.