Semiquantification of circulating hepatocellular carcinoma cells by reverse transcriptase polymerase chain reaction

Liquid biopsy for liver diseases

With the growing number of novel therapeutic approaches for liver diseases, significant research efforts have been devoted to the development of liquid biopsy tools for precision medicine. This can be defined as non-invasive reliable biomarkers that can supplement and eventually replace the invasive liver biopsy for diagnosis, disease stratification and monitoring of response to therapeutic interventions. Similarly, detection of liver cancer at an earlier stage of the disease, potentially susceptible to curative resection, can be critical to improve patient survival. Circulating extracellular vesicles, nucleic acids (DNA and RNA) and tumour cells have emerged as attractive liquid biopsy candidates because they fulfil many of the key characteristics of an ideal biomarker. In this review, we summarise the currently available information regarding these promising and potential transformative tools, as well as the issues still needed to be addressed for adopting various liquid biopsy approaches into clinical practice. These studies may pave the way to the development of a new generation of reliable, mechanism-based disease biomarkers.

MT1-MMP Responsive Doxorubicin Conjugated Poly(lactic-co-glycolic Acid)/Poly(styrene-alt-maleic Anhydride) Core/Shell Microparticles for Intrahepatic Arterial Chemotherapy of Hepatic Cancer

In this study, we demonstrated that the MT1-MMP-responsive peptide (sequence: GPLPLRSWGLK) and doxorubicin-conjugated poly(lactic-co-glycolic acid/poly(styrene-alt-maleic anhydride) core/shell microparticles (PLGA/pSMA MPs) can be applied for intrahepatic arterial injection for hepatocellular carcinoma (HCC). PLGA/pSMA MPs were prepared with a capillary-focused microfluidic device. The particle size, observed by scanning electron microscopy (SEM), was around 22 ± 3 μm. MT1-MMP-responsive peptide and doxorubicin (DOX) were chemically conjugated with pSMA segments on the shell of MPs to form a PLGA/pSMA-peptide-DOX complex, resulting in high encapsulation efficiency (91.1%) and loading content (2.9%). DOX was released from PLGA/pSMA-peptide-DOX MPs in a pH-dependent manner (∼25% at pH 5.4 and ∼8% at pH 7.4) and accumulated significantly in an MT1-MMP-overexpressing Hep3B cell line. An in vivo intrahepatic injection study showed localization of MPs on the hepatic vessels and hepatic lobes up to 24 h after the injection without any shunting to the lung. Moreover, MPs efficiently inhibited tumor growth of Hep3B hepatic tumor xenografted mouse models. We expect that PLGA/pSMA-peptide-DOX MPs can be utilized as an effective intrahepatic drug delivery system for the treatment of HCC.

Adjuvant radiotherapy in centrally located hepatocellular carcinomas after hepatectomy with narrow margin (<1 cm): a prospective randomized study

BACKGROUND

Although radiotherapy (RT) provides potential benefits for patients with hepatocellular carcinomas (HCCs) that are unsuitable for operation, the specific role of adjuvant RT in HCC after hepatectomy remains ill defined. The current study's aim was to evaluate the safety and efficacy of adjuvant RT for centrally located HCCs after narrow-margin (<1 cm) hepatectomy.

STUDY DESIGN

The study included 119 patients with centrally located HCCs who underwent narrow-margin hepatectomy between July 2007 and March 2012. Patients were prospectively randomized to receive adjuvant RT (n = 58) or were assigned to a control group (n = 61). Surgical outcomes, safety, and survival rates were evaluated.

RESULTS

Hepatectomy was successfully performed in all patients. No cases of radiation-induced liver disease were observed. One-, 3-, and 5-year recurrence-free survival rates were 78.1%, 56.5%, and 36.9% in the adjuvant RT group and 72.4%, 40.1%, and 16.0% in the control group, respectively (p = 0.06, log-rank test). Corresponding overall survival rates were 96.2%, 72.6%, 48.4%, and 89.6%, 74.5%, 37.2%, respectively (p = 0.48, log-rank test). One-, 3-, and 5-year recurrence-free survival rates in patients with small-diameter tumors (≤5 cm) were 88.8%, 67.4%, 42.9% in the adjuvant RT group and 82.3%, 42.9%, 21.5% in the control group (p = 0.03, log-rank test). Corresponding overall survival rates were 97.5%, 75.3%, 75.3%, and 94.7%, 84.1%, 65.4%, respectively (p = 0.92, log-rank test).

CONCLUSIONS

Adjuvant RT for centrally located HCCs after narrow-margin hepatectomy was technically feasible and relatively safe. No significant between-group difference was observed in recurrence-free and overall survival. The post-hoc subgroup comparison showed that adjuvant RT improved recurrence-free survival considerably, but not overall survival, in patients with small HCCs (≤5 cm). More in-depth studies are needed to validate this finding.

Clinical outcomes of radiofrequency ablation and surgical resection for small hepatocellular carcinoma: a meta-analysis

BACKGROUND AND AIM

To evaluate the evidence comparing radiofrequency ablation (RFA) and surgical resection (RES) on the treatment of hepatocellular carcinoma (HCC) using meta-analytical techniques.

METHODS

Literature search was undertaken until March 2011 to identify comparative studies evaluating survival rates, recurrence rates, and complications. Pooled odds ratios (OR) and 95% confidence intervals (95% CI) were calculated with either the fixed or random effect model.

RESULTS

These studies included a total of 877 patients: 441 treated with RFA and 436 treated with RES. The overall survival was significantly higher in patients treated with RES than RFA at 1, 3 and 5 years (respectively: OR: 0.50, 95% CI: 0.29-0.86; OR: 0.51, 95% CI: 0.28-0.94; OR: 0.62, 95% CI: 0.45-0.84). In the RES group the 1, 3, and 5 years recurrence-free survival rates were significantly higher than the RFA group (respectively: OR: 0.65, 95% CI: 0.44-0.97; OR: 0.65, 95% CI: 0.47-0.89; OR: 0.52, 95% CI: 0.35-0.77). RFA had a higher rate of local recurrence (OR: 4.08, 95% CI: 2.03-8.20). For tumors ≤ 3 cm RES was better than RFA in the 3-year overall survival rates (OR: 0.38, 95% CI: 0.16-0.89).

CONCLUSIONS

Surgical resection was superior to RFA in the treatment of HCC. However, the findings have to be carefully interpreted due to the lower level of evidence.

Circulating tumor cells measurements in hepatocellular carcinoma

Liver cancer is the fifth most common cancer in men and the seventh in women. During the past 20 years, the incidence of HCC has tripled while the 5-year survival rate has remained below 12%. The presence of circulating tumor cells (CTC) reflects the aggressiveness nature of a tumor. Many attempts have been made to develop assays that reliably detect and enumerate the CTC during the development of the HCC. In this case, the challenges are (1) there are few markers specific to the HCC (tumor cells versus nontumor cells) and (2) they can be used to quantify the number of CTC in the bloodstream. Another technical challenge consists of finding few CTC mixed with million leukocytes and billion erythrocytes. CTC detection and identification can be used to estimate prognosis and may serve as an early marker to assess antitumor activity of treatment. CTC can also be used to predict progression-free survival and overall survival. CTC are an interesting source of biological information in order to understand dissemination, drug resistance, and treatment-induced cell death. Our aim is to review and analyze the different new methods existing to detect, enumerate, and characterize the CTC in the peripheral circulation of patients with HCC.

Vitamin analogues in chemoprevention of hepatocellular carcinoma after resection or ablation--a systematic review and meta-analysis

OBJECTIVE

While hepatic resection or local ablative therapy may provide a potentially curative treatment for hepatocellular carcinoma (HCC), more than half of these patients develop recurrent HCC within 5 years after treatment. Thus identification of any therapy which can decrease or delay the incidence of recurrence will improve the results of treatment. However, no chemopreventive agent has been approved for HCC.

METHODS

A MEDLINE database, Embase, Cancerlit (National Cancer Institute), and CBM (Chinese Biomedical Database) search from 1990 to 2009 was performed to identify relevant articles using the keywords "hepatocellular carcinoma," "vitamin analogue," and "chemoprevention." Additional papers were identified by a manual search of the references from the key articles. The fixed effect model was used for a meta-analysis.

RESULTS

Oral administration of acyclic retinoids (vitamin A analogue), and menatetrenone (vitamin K2 analogue) have been tested as chemopreventive agents after hepatic resection or local ablative therapy for HCC. There were one and four randomised, controlled trials (RCTs) which evaluated the efficacy of polyprenoic acid and menatetrenone, respectively. All studies were conducted in Japan. One RCT showed the preventive effect of polyprenoic acid in lowering the incidence of HCC recurrence after hepatic resection or percutaneous ethanol injection, and this effect lasted up to 199 weeks after randomization (or 151 weeks after completion of retinoid administration). Four RCTs evaluated the preventive efficacy of menatetrenone on HCC recurrence after hepatic resection or local ablative therapy. The results of three studies, as well as the meta-analysis of all four studies, showed significantly better tumour recurrence-free survival. The beneficial effect on the overall survival was less definite.

CONCLUSION

There is evidence to suggest that chemopreventive therapy after partial hepatectomy or local ablative therapy is beneficial in prolonging disease-free survival, but the evidence is less for an effect on the overall survival. To confirm the beneficial role of vitamin A or K analogues in the chemoprevention of HCC further and larger randomised trials are now required.

MAGE-3 and MAGE-4 genes as possible markers for early detection of metastases in hepatitis C virus Egyptian patients complicated by hepatocellular carcinoma

The dissemination of hepatocellular carcinoma (HCC) cells into the circulation plays a critical role in post-operative recurrence and metastasis. Early detection of metastatic tumor cells is critical to identify HCC patients at high risk of relapse. MAGE-3 and -4 genes were evaluated by reverse transcription polymerase chain reaction for the possibility of using them as new markers for early detection of metastases in 160 chronic HCV Egyptian patients, 115 of them were complicated with HCC. The expressions of MAGE-3 and MAGE-4 mRNA in peripheral blood of patients with metastatic HCC were 36 and 52%, respectively. While the expressions of MAGE-3 and MAGE-4 mRNA in peripheral blood of patients with localized HCC were 12.5 and 15%, respectively. Moreover, at least one type of mRNA was found in the peripheral blood of 68% of the metastatic HCC patients and in 20% of the localized HCC patients. While neither the controls nor the cirrhotic patients show expression of MAGE-4 mRNA in their peripheral blood. MAGE-3 and MAGE-4 may be a promising diagnostic tool for monitoring the prognosis of HCC patients and early detection of occult hematogenous metastasis of HCC.

A novel biomarker TERTmRNA is applicable for early detection of hepatoma

Backgrounds

We previously reported a highly sensitive method for serum human telomerase reverse transcriptase (hTERT) mRNA for hepatocellular carcinoma (HCC). α-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP) are good markers for HCC. In this study, we verified the significance of hTERTmRNA in a large scale multi-centered trial, collating quantified values with clinical course.

Methods

In 638 subjects including 303 patients with HCC, 89 with chronic hepatitis (CH), 45 with liver cirrhosis (LC) and 201 healthy individuals, we quantified serum hTERTmRNA using the real-time RT-PCR. We examined its sensitivity and specificity in HCC diagnosis, clinical significance, ROC curve analysis in comparison with other tumor markers, and its correlations with the clinical parameters using Pearson relative test and multivariate analyses. Furthermore, we performed a prospective and comparative study to observe the change of biomarkers, including hTERTmRNA in HCC patients receiving anti-cancer therapies.

Results

hTERTmRNA was demonstrated to be independently correlated with clinical parameters; tumor size and tumor differentiation (P < 0.001, each). The sensitivity/specificity of hTERTmRNA in HCC diagnosis showed 90.2%/85.4% for hTERT. hTERTmRNA proved to be superior to AFP, AFP-L3, and DCP in the diagnosis and underwent an indisputable change in response to therapy. The detection rate of small HCC by hTERTmRNA was superior to the other markers.

Conclusions

hTERTmRNA is superior to conventional tumor markers in the diagnosis and recurrence of HCC at an early stage.

Aberrant concentrations of liver-derived plasma albumin mRNA in liver pathologies

BACKGROUND

We hypothesized that liver-derived mRNA, such as ALB (albumin) mRNA, would be released into human plasma with liver cell death.

METHODS

We genotyped ALB mRNA molecules in samples of plasma and whole blood from liver and bone marrow transplant recipients by RNA single-nucleotide polymorphism analysis. Plasma and whole blood ALB mRNA genotypes were compared with the DNA genotypes of the recipients and donors. A reverse-transcription quantitative real-time PCR assay was used to measure plasma ALB mRNA concentrations in 107 patients [hepatocellular carcinoma (HCC), cirrhosis, or chronic hepatitis B (CHB)] and 207 healthy controls.

RESULTS

The RNA genotype data revealed ALB mRNA in plasma to be liver derived, whereas tissue compartments other than the liver also contributed to the ALB mRNA detected in whole blood. Statistically significant increases in plasma ALB mRNA concentrations were observed for HCC, cirrhosis, and active CHB, compared with controls. A cutoff of 835 copies/mL of plasma ALB mRNA identified by ROC curve analysis showed 85.5% diagnostic sensitivity and 92.8% diagnostic specificity for the detection of liver pathologies. Only 21.5% of patients with liver pathologies had increased alanine aminotransferase (ALT) activities, whereas 73.8% had increased plasma ALB mRNA concentrations. Only 48.6% of the HCC patients had increased serum alpha-fetoprotein concentrations, whereas 91.4% had increased plasma ALB mRNA concentrations.

CONCLUSIONS

ALB mRNA is liver specific in plasma, but not in whole blood. Plasma ALB mRNA is increased in some liver pathologies and may be more diagnostically sensitive than alpha-fetoprotein and ALT.

Translating the metastasis paradigm from scientific theory to clinical oncology

Cancer metastasis contributes to significant morbidity and mortality. Patients with metastatic cancer, often considered incurable, are provided with either supportive care or aggressive management without curative intent. Despite decades of research toward unraveling cancer progression mechanisms, the current body of knowledge has not translated into effective antimetastasis therapies, but recent findings challenge the classic notion that metastases develop during the late stages of carcinogenesis. Here, we evaluate the scientific evidence in the context of the multistage metastasis model. The resolution of current controversies has implications on both the prognostic value of molecular technology and the future of targeted therapies for the clinical benefit of metastasis patients.

A prospective, randomized, controlled trial of preoperative transarterial chemoembolization for resectable large hepatocellular carcinoma

OBJECTIVE

To evaluate the effect of preoperative transarterial chemoembolization (TACE) for resectable large hepatocellular carcinoma (HCC).

SUMMARY BACKGROUND DATA

Resection of HCC is potentially curative, but local recurrence is very common. There is currently no effective neoadjuvant or adjuvant therapy.

METHODS

From July 2001 to December 2003, 108 patients (hepatitis B carrier = 98.1%) with resectable HCC (> or =5 cm) was randomly assigned to preoperative TACE treatment (n = 52) or no preoperative treatment (control group) (n = 56).

RESULTS

Five patients (9.6%) in the preoperative TACE group did not receive surgical therapy because of extrahepatic metastasis or liver failure. The preoperative TACE group had a lower resection rate (n = 47, 90.4% vs. n = 56, 100%; P= 0.017), and longer operative time (mean, 176.5 minutes vs. 149.3 minutes; P= 0.042). No significant difference was found between the 2 groups in operative blood loss, surgical morbidity, and hospital mortality.At a median follow-up of 57 months, 41 (78.8%) of 52 patients in the preoperative TACE group and 51 (91.1%) of 56 patients in the control group had recurrent disease (P= 0.087). The 1-, 3-, and 5-year disease-free survival rates were 48.9%, 25.5%, and 12.8%, respectively, for the preoperative TACE group and 39.2%, 21.4%, and 8.9%, respectively, for the control group (P= 0.372). The 1-, 3-, and 5-year overall survival rates were 73.1%, 40.4%, and 30.7%, respectively, for the preoperative TACE group and 69.6%, 32.1%, and 21.1%, respectively, for the control group (P= 0.679).

CONCLUSIONS

Preoperative TACE did not improve surgical outcome. It resulted in drop-out from definitive surgery because of progression of disease and liver failure.

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.

Adjuvant intra-arterial iodine-131-labeled lipiodol for resectable hepatocellular carcinoma: a prospective randomized trial-update on 5-year and 10-year survival

OBJECTIVE

In this prospective randomized trial, we attempted to find out if 1 dose of postoperative adjuvant intra-arterial iodine-131-labeled lipiodol could reduce the rate of local recurrence, and increase disease-free and overall survival for patients with hepatocellular carcinoma (HCC). This study evaluated the long-term outcome.

BACKGROUND

Resection of HCC is potentially curative, but local recurrence is common. However, there is currently no effective adjuvant therapy. Early results after closing the trial (Lau et al. Lancet 1999;353:797-801) showed that 1 dose of intra-arterial I-lipiodol given after curative resection significantly decreased the rate of recurrence, and increased disease-free and overall survival.

METHODS

Patients who underwent curative resection for HCC and recovered within 6 weeks were randomly assigned one 1850 MBq dose of I-lipiodol or no further treatment (controls). We compared rates of recurrence, and long-term disease-free and overall survival (the primary endpoints) between the 2 groups by intention-to-treat.

RESULTS

Between April 1992 and August 1997, we recruited 43 patients: 21 were randomized to receive intra-arterial I-lipiodol and 22 to receive no adjuvant treatment. I-lipiodol had no significant toxic effects. During a median follow-up of 66 (range, 3-198) months, there were 10 (47.6%) recurrences among the 21 patients in the adjuvant treatment group, compared with 14 (63.6%) in the control group (P = 0.29). The actuarial 5-year disease-free survival in the treatment and control groups was 61.9% and 31.8%, respectively (P = 0.0397). The actuarial 5-year overall survival in the treatment and control groups was 66.7% and 36.4%, respectively (P = 0.0433). The actuarial 7-year disease-free survival in the treatment and control groups was 52.4% and 31.8%, respectively (P = 0.0224). The actuarial 7-year overall survival in the treatment and control groups was 66.7% and 31.8%, respectively (P = 0.0243). The actuarial 10-year disease-free survival in the treatment and control groups was 47.6% and 27.3%, respectively (P = 0.0892). The actuarial 10-year overall survival in the treatment and control groups was 52.4% and 27.3%, respectively (P = 0.0905).

CONCLUSIONS

In patients with HCC, adjuvant intra-arterial I-lipiodol after curative liver resection provided survival benefit on the disease-free survival and overall survival, although the difference became statistically insignificant at 8 years after randomization.

Association between recurrence of hepatocellular carcinoma and alpha-fetoprotein messenger RNA levels in peripheral blood

PURPOSE

Intra- and extrahepatic recurrence is common, even after curative resection for hepatocellular carcinoma (HCC), suggesting preoperative or intraoperative tumor cell dissemination. Reverse transcription - polymerase chain reaction (RT-PCR) for alpha-fetoprotein (AFP) is used to detect circulating liver cancer cells. We previously developed a quantitative method that allows estimation of the AFP mRNA level by real-time PCR. In the present study, we used this method to measure the AFP mRNA level before and after resection of HCC, then correlated the findings with various clinicopathological characteristics and prognosis.

METHODS

We prospectively examined peripheral blood samples from 38 patients with HCC, and bone marrow aspirate from 25 of these patients. As a control, we examined bone marrow from 20 patients with benign diseases. The follow-up period ranged from 32 to 66 months. Real-time RT-PCR was used to detect AFP mRNA levels in the samples.

RESULTS

AFP was expressed in 9 (23.7%) of the 38 peripheral blood samples. The detection of AFP mRNA was significantly correlated with extrahepatic metastasis after primary surgery, and a shorter disease-free survival time (P = 0.0245 each). Bone marrow samples were defined as positive if they expressed AFP mRNA at levels higher than the maximum expressed level in the controls, because only 1 (5%) of the 20 control bone marrow samples had low AFP mRNA expression. Using this cutoff level, 12 (48%) of the 25 patients with HCC had positivity for AFP mRNA. The results of bone marrow RT-PCR did not correlate with the clinocopathological characteristics of prognosis.

CONCLUSIONS

Using real-time PCR to measure the AFP mRNA level in blood, but not bone marrow, could be useful for predicting postoperative tumor recurrence.

Serum human telomerase reverse transcriptase messenger RNA as a novel tumor marker for hepatocellular carcinoma

PURPOSE

We previously reported the usefulness of a qualified highly sensitive detection method for human telomerase reverse transcriptase (hTERT) mRNA in serum with 89.7% sensitivity for hepatocellular carcinoma (HCC). In this study, we developed a quantitative detection method for serum hTERT mRNA and examined the clinical significance in HCC diagnosis. EXPERIMENTAL BACKGROUND: In 64 patients with HCC, 20 with liver cirrhosis, 20 with chronic hepatitis, and 50 healthy individuals, we measured serum hTERT mRNA by using the newly developed real-time quantitative reverse transcription-PCR with SYBR Green I. We examined its sensitivity and specificity in HCC diagnosis, clinical significance in comparison with other tumor markers, and its correlations with the clinical variables by using multivariate analyses.

RESULTS

Serum hTERT mRNA showed higher values in patients with HCC than those with chronic liver diseases. hTERT mRNA expression was shown to be independently correlated with clinical variables such as tumor size, number, and degree of differentiation (P < 0.001, each). The sensitivity/specificity of hTERT mRNA and alpha-fetoprotein (AFP) mRNA in HCC diagnosis were 88.2%/70.0% for hTERT and 71.6%/67.5% for AFP, respectively. hTERT mRNA proved to be superior to AFP mRNA, AFP, and des-gamma-carboxy prothrombin in HCC diagnosis. Furthermore, hTERT mRNA in serum was associated with that in HCC tissue.

CONCLUSIONS

The usefulness of hTERT mRNA expression in HCC diagnosis and its superiority to conventional tumor markers were shown. Therefore, serum hTERT mRNA is a novel and available marker for HCC diagnosis.

Detection and clinical significance of bone marrow micrometastases in patients undergoing liver transplantation for hepatocellular carcinoma

BACKGROUND

Existing methods of selecting patients with hepatocellular carcinoma (HCC) for liver transplantation rely on computed tomography and magnetic resonance imaging, which fail to detect vascular invasion or micrometastases. Vascular invasion cannot be assessed pretransplant because of the risks of tumor biopsy. Pretransplant detection of micrometastases in bone marrow is an alternative method that may identify patients at risk of recurrence and permit better organ allocation. The authors' aim was to develop an accurate method of detecting hepatocellular carcinoma micrometastases that may have a clinical role in pretransplant assessment.

METHODS

Iliac crest bone marrow was sampled from 18 patients with HCC (before liver transplantation) and 14 controls (cirrhosis, 9; hematologic disorders, 5). Mononuclear bone marrow fractions were evaluated for the presence of micrometastases by immunocytochemistry (ICC) using Hep Par-1 (HPICC) and Glypican-3 (GPICC), and by reverse-transcriptase (RT) polymerase chain reaction using two primer pairs targeting albumin (Alb1RT and Alb2RT) and one pair targeting alpha-fetoprotein (AFPRT). Each marker was compared in terms of (1) specificity and (2) positive and negative predictive values for tumor recurrence.

RESULTS

The specificity of each marker for detecting HCC micrometastases were as follows: HPICC, 93%; GPICC, 92%; Alb1RT, 33%; Alb2RT, 59%; and AFPRT, 0%. The positive (negative) predictive values for HPICC, GPICC, and Alb2RT for posttransplant tumor recurrence were 42% (100%), 40% (73%), and 0% (43%), respectively. HPICC-positive micrometastases were identified in all patients with postoperative tumor recurrence (n=5) and in 75% of patients with microscopic vascular invasion.

CONCLUSIONS

Detection of HCC micrometastases in bone marrow of potential liver transplant candidates is a potentially useful technique that may provide important prognostic information without the need for preoperative tumor biopsy. The authors' preliminary data indicate that HPICC is a promising immunocytochemical marker for HCC micrometastases, and larger studies are needed to confirm its clinical role.

Ubiquitous aberrant RASSF1A promoter methylation in childhood neoplasia

PURPOSE AND EXPERIMENTAL DESIGN

The role of RASSF1A has been elucidated recently in regulating apoptosis and cell cycle progression by inhibiting cyclin D1 accumulation. Aberrant RASSF1A promoter methylation has been found frequently in multiple adult cancer types. Using methylation-specific PCR and reverse transcription-PCR, we investigated epigenetic deregulation of RASSF1A in primary tumors, adjacent nontumor tissues, secondary metastases, peripheral blood cells, and plasma samples from children with 18 different cancer types, in association with their clinicopathologic features.

RESULTS

Regardless of the tumor size, ubiquitous RASSF1A promoter methylation was found in 67% (16 of 24) of pediatric tumors, including neuroblastoma, thyroid carcinoma, hepatocellular carcinoma, pancreatoblastoma, adrenocortical carcinoma, Wilms' tumor, Burkitt's lymphoma, and T-cell lymphoma. A majority (75%) of pediatric cancer patients with tumoral RASSF1A methylation was male. Methylated RASSF1A alleles were also detected in 4 of 13 adjacent nontumor tissues, suggesting that this epigenetic change is potentially an early and critical event in childhood neoplasia. RASSF1A promoter methylation found in 92% (11 of 12) of cell lines largely derived from pediatric cancer patients was significantly associated with transcriptional silencing/repression. After demethylation treatment with 5-aza-2'-deoxycytidine, transcriptional reactivation was shown in KELLY, RD, and Namalwa cell lines as analyzed by reverse transcription-PCR. For the first time, RASSF1A methylation was detected in 54% (7 of 13), 40% (4 of 10), and 9% (1 of 11) of buffy coat samples collected before, during, and after treatment, correspondingly, from pediatric patients with neuroblastoma, thyroid carcinoma, hepatocellular carcinoma, rhabdomyosarcoma, Burkitt's lymphoma, T-cell lymphoma, or acute lymphoblastic leukemia. Concordantly, RASSF1A methylation was found during treatment in plasma of the same patients, suggesting cell death and good response to chemotherapy.

CONCLUSIONS

RASSF1A methylation in tumor or buffy coat did not correlate strongly with age, tumor size, recurrence/metastasis, or overall survival in this cohort of pediatric cancer patients. Of importance, epigenetic inactivation of RASSF1A may potentially be crucial in pediatric tumor initiation.

Does percutaneous liver biopsy of hepatocellular carcinoma cause hematogenous dissemination? An in vivo study with quantitative assay of circulating tumor DNA using methylation-specific real-time polymerase chain reaction

OBJECTIVE

Our purpose was to find out whether percutaneous biopsy of hepatocellular carcinoma will cause significant dissemination of tumor into the circulation by quantitative analysis of circulating tumor DNA.

SUBJECTS AND METHODS

In this prospective study of 32 patients with suspected hepatocellular carcinoma who underwent sonographically guided liver biopsy, a peripheral venous blood sample was obtained before and 5 min after the procedure. Biopsy was performed using an 18-gauge biopsy gun. DNA was extracted from the plasma of the blood samples for methylation-specific polymerase chain reaction. Quantitative measures of the plasma tumor DNA were determined with real-time quantitative polymerase chain reaction, and the amount was expressed as a methylation index (%) in plasma.

RESULTS

Nineteen (59.4%) of 32 patients did not have detectable p16 tumor suppressor gene marker (p16M) in plasma before biopsy, and they showed no detectable plasma p16M after biopsy. Thirteen (65%) of 20 patients had p16M identified in the plasma before liver biopsy. Quantitative analysis of the plasma tumor DNA in these 13 patients showed no statistically significant difference in the methylation index before and after biopsy (p = 0.345, Wilcoxon's signed rank test).

CONCLUSION

No evidence exists that percutaneous liver biopsy results in hematogenous dissemination of hepatocellular carcinoma as shown by quantitative analysis of circulating tumor DNA (p16M) using methylation-specific real-time polymerase chain reaction.

Circulating tumor cells in patients with solid malignancy treated by high-intensity focused ultrasound

The theoretical possibility that exposure of a solid malignancy to high-intensity focused ultrasound (US), or HIFU, could lead to an increased rate of metastasis still remains. Using reverse transcriptase polymerase chain reaction (RT-PCR), the potential risk of hematogenous dissemination was assessed in HIFU-treated patients with solid malignancy. RT-PCR can demonstrate the presence or absence of specific RNA fragments. On the day before HIFU ablation, 5-mL peripheral blood samples were collected, and again 5 to 7 days after HIFU, from 26 enrolled patients (hepatocellular carcinoma, HCC: 10; osteosarcoma: 16). Total RNA was isolated and RT-PCR was performed to analyze the mRNA expression of (alpha-fetoprotein (AFP) and bone-specific alkaline phosphatase (BALP) genes. Positive AFP mRNA expression was preoperatively detected in 8 of 10 patients with HCC. In the postoperative specimens, positive expression was also detected in 8 of 10 patients. In 2 patients, circulating tumor cells were found preoperatively, but not postoperatively. Conversely, 2 patients with no circulating tumor cells preoperatively were found to have circulating tumor cells after HIFU. Of 16 osteosarcoma patients, 12 patients had circulating tumor cells and 4 had none. After HIFU treatment, 2 of the 12 patients had converted from presence to absence of circulating cells and the remaining 4 patients remained negative. It is concluded that patients undergoing complete HIFU ablation may demonstrate conversion from presence to absence of circulating tumor-specific marker mRNA, and that HIFU would not enhance the potential risk of metastasis in patients with malignant diseases.

New markers for cancer detection

Circulating tumor nucleic acids in blood have been demonstrated to reflect the biologic characteristics of tumors. During tumor progression, aberrant DNA methylation can lead to transcriptional silencing of tumor suppressor genes, DNA repair genes, and metastasis-inhibitor genes. Hypermethylation of multiple genes, detectable in the blood of cancer patients, has demonstrated increasing promise as a specific and sensitive molecular marker for detecting and monitoring cancer. In addition to these epigenetic markers, a number of mRNA markers may also enable cancer detection in the blood of patients with different cancer types. Quantification of circulating tumor cell mRNAs in cancer patients appears to be useful for monitoring cancer progression and response to treatment. DNA methylation markers and mRNA markers in the blood may open up diagnostic and prognostic possibilities.

Cooperative role of E-cadherin and sialyl-Lewis X/A-deficient MUC1 in the passive dissemination of tumor emboli in inflammatory breast carcinoma

Inflammatory breast carcinoma (IBC) is characterized by florid tumor emboli within lymphovascular spaces termed lymphovascular invasion (LVI). Using a human-scid model of IBC (MARY-X), we have demonstrated using retrovirally-mediated dominant-negative E-cadherin mutant approaches (H-2K(d)-E-cad), that the tumor cell embolus (IBC spheroid) forms on the basis of an intact and overexpressed E-cadherin/alpha, beta-catenin axis which mediates tumor cell-tumor cell adhesion analogous to the embryonic blastocyst and accounts for the compactness of the embolus. The tumor cell embolus (IBC spheroid), in contrast, fails to bind the surrounding vascular endothelial cells both in vitro and in vivo because of markedly decreased sialyl-Lewis X/A carbohydrate ligand-binding epitopes on its overexpressed MUC1 which are necessary for binding endothelial cell E-selectin. This tumor cell-endothelial cell aversion further contributes to the compactness of the IBC spheroid and its passivity in metastasis dissemination. This passivity is manifested by a dramatic increase in metastatic pulmonary emboli following palpation of the primary tumor. In assessing this passivity of metastatic dissemination, we compared the effects of palpation on MARY-X with the effects of palpation on a derived dominant-negative E-cadherin mutant (H-2K(d)-E-cad), as well as other well known human tumoral xenografts exhibiting no (MCF-7, T47D), low (MDA-MB-231, MDA-MB-468) or high (C8161, M24(met)) levels of spontaneous metastasis but no LVI. Palpation of each xenograft similarly increased intratumoral pressure by 200% (10-->30 mmHg) but dramatically increased the numbers and sizes of pulmonary metastases 10-100-fold (P<0.001) only in MARY-X. The mechanism of this effect was through an immediate post-palpation release of circulating tumor emboli detected 2-3 min after palpation (P<0.01) by human cytokeratin 19 RT-PCR of extracted RNA from 300 microl of murine blood. Although circulating human tumor cell-derived growth factors (IGF-I, IGF-II, TGF-alpha and TGF-beta) and angiogenic factors (VEGF and bFGF) were detected by ELISA in murine serum of MARY-X, palpation did not further increase the circulating levels of these factors (P>0.1). Our findings support the cooperative role of E-cadherin and sialyl-Lewis X/A-deficient MUC1 in the passive dissemination of tumor emboli in IBC.

Evaluation of MAGE-1 and MAGE-3 as tumour-specific markers to detect blood dissemination of hepatocellular carcinoma cells

The members of MAGE gene family are highly expressed in human hepatocellular carcinoma (HCC). In the present study, we tested the tumour-specific MAGE-1 and MAGE-3 transcripts in the peripheral blood of HCC patients by nested RT-PCR to detect the circulating tumour cells and evaluate their potential clinical implication. Of 30 HCC patients, the positive rate of MAGE-1 and MAGE-3 transcripts was 43.3% (13 out of 30) and 33.3% (10 out of 30) in PBMC samples, whilst the positive rate was 70% (21 out of 30) and 53.3% (16 out of 30) in the resected HCC tissue samples, respectively. The positivity for at least one MAGE gene transcript was 63.3% (19 out of 30) in PBMC samples of HCC patients and 83.3% (25 out of 30) in the resected HCC tissue samples. MAGE-1 and/or MAGE-3 mRNA were not detected in the PBMC of those patients from whom the resected HCC tissues were MAGE-1 or MAGE-3 mRNA negative, nor in the 25 PBMC samples from healthy donors. The detection of MAGE transcripts in PBMC was correlated with the advanced stages and tumour size of the HCC, being 82.4% (14 out of 17) in tumour stages III and IVa, 56.6% (five out of nine) in stage II, and null (nought out of four) in stage I. The serum alpha-FP in 33.3% (10 out of 30) of HCC patients was normal or slightly elevated (< 40 ng ml(-1)). However, six of these 10 patients (alpha-FP < 40 ng ml(-1)) were MAGE-1 and /or MAGE-3 mRNA positive in their PBMC. The follow-up survey of MAGE mRNA in PBMC was performed in 12 patients. Seven patients with persistent MAGE-1 and/or MAGE-3 mRNA positive or from negative turned to positive died because of metastasis and/or recurrence. In striking contrast, all four patients with MAGE-1 and/or MAGE-3 mRNA from positive turned to negative and one patient with persistent MAGE-3 transcript negative are alive after last test. Collectively, detection of MAGE transcripts with follow-up survey in PBMC is a feasible and reliable assay for the early prediction of the relapse and prognosis of the HCC patients.

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.

Analysis of tumor characteristics and survival in liver transplant recipients with incidentally diagnosed hepatocellular carcinoma

The use of orthotopic liver transplantation (OLTX) for the treatment of hepatocellular carcinoma (HCC) has generally become restricted to carefully selected cases of small oligocentric tumors. However, it is not uncommon to find previously undetected HCC within recipient cirrhotic livers at the time of hepatectomy. The impact of unsuspected HCC on patient outcomes remains unclear. A retrospective analysis of our institutional experience with adult primary OLTX was performed comparing recipients with incidental HCC (group 1), recipients with known or suspected HCC (group 2), and recipients confirmed by pathologic examination to be tumor free (group 3). Between 1984 and 2000, 27 patients in group 1, 12 patients in group 2, and 612 patients in group 3 underwent primary OLTX. Tumors were smaller (P = 0.0172) in group 1 than in group 2; however, the number of tumors and the histologic findings were similar in the groups. Incidence of bilobar involvement, vascular invasion, portal vein tumor thrombus, lymphatic involvement, and distant metastasis at the time of OLTX did not differ significantly between these groups. Four-year patient survival appeared to be lower in group 1 (70.0%) than in group 3 (79.0%) (P = 0.0546); 4-year patient survival was significantly worse in group 2 (31.0%) compared to group 3 (P = 0.0106). Thus, in our experience, incidentally diagnosed cases of HCC possess many of the same features of malignancy as preoperatively diagnosed HCC. Indeed, patient survival after OLTX appears to be adversely affected by the presence of incidental HCC.

Circulating tumor cell mRNAs in peripheral blood from hepatocellular carcinoma patients under radiotherapy, surgical resection or chemotherapy: a quantitative evaluation

We assessed whether current therapies could lead to hematogenous dissemination of malignant hepatocytes in hepatocellular carcinoma (HCC) patients using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) for alpha-fetoprotein (afp) and albumin (alb) mRNAs. We analyzed 137 peripheral blood samples before, during and after treatment from 84 patients under radiotherapy, surgical resection or chemotherapy. As compared to the upper limit for 53 healthy/non-HCC controls, alb- mRNA levels increased 2-10-fold in 6% of patients pre-treatment and 2-2.6x10(4)-fold in 32% post-treatment. Levels of afp- mRNA increased 3-210-fold in 17% pre-treatment and 4-5x10(5)-fold in 30% post-treatment. During a longitudinal follow-up of eight patients under radiotherapy or radiotherapy/resection, alb-mRNA levels were normal before treatment, whereas afp-mRNA levels increased 10-fold in two patients. During treatment, alb-mRNA and afp-mRNA levels increased 2-61-fold in three patients and 2.5-5-fold in two patients, respectively. After treatment, alb-mRNA levels declined to normal in all three patients within 3.5 months, but afp-mRNA levels increased 127-5x10(5)-fold in three patients within 5 months. We show evidence that HCC cells disseminating mostly post-treatment may be the 'seed' of recurrence/metastasis. In conjunction with the serum alpha-fetoprotein test, sequential afp-mRNA quantification could predict clinical metastasis/recurrence in 56% of patients during a 4-year follow-up.

Minimal residual disease in gastrointestinal cancer

Tumor progression after curative resection of gastrointestinal carcinomas is probably caused by pre- or intraoperative tumor cell dissemination. Disseminated tumor cells are generally detected by immunohistochemistry- or PCR-based molecular-biology methods. A consensus on which is the most adequate detection method has not yet been found, which makes the comparison of data difficult. The prognostic relevance of disseminated cells has been shown, at least in part, for esophageal, gastric, pancreatic, and colonic cancer. The data regarding hepatocellular cancer is conflicting. This article gives a critical review of tumor cell detection in gastrointestinal cancer.

Molecular characterization of minimal residual cancer cells in patients with solid tumors

The failure to reduce the mortality of patients with solid tumors is mainly a result of the early dissemination of cancer cells to secondary sites, which is usually missed by conventional diagnostic procedures used for tumor staging. PCR was shown to be superior to conventional techniques in detecting circulating tumor cells and micrometastases allowing the identification of one tumor cell in up to 10(7) normal cells in various sources such as blood, bone marrow, lymph nodes, urine or stool. The methods used are based on the detection of either genomic alterations in oncogenes and tumor suppressor genes or on the mRNA expression of tissue-specific and tumor-associated genes. The additional implementation of techniques for cancer cell purification had a significant impact on analytical sensitivity and specificity of MRCC detection. For patients with e.g. melanoma, breast, colorectal or prostate cancer it was demonstrated that the presence of disseminated cancer cells defines a subgroup of patients with reduced time to recurrence. The possibility to use easily accessible body fluids as a source for MRCC detection enables longitudinal observations of the disease. In this review we discuss the potential of molecular characterization of MRCC as a tool to improve prognostication, therapy selection and drug targeting as well as therapy monitoring.

Quantitative relationship of the circulating tumor burden assessed by reverse transcription-polymerase chain reaction for cytokeratin 19 mRNA in peripheral blood of colorectal cancer patients with Dukes' stage, serum carcinoembryonic antigen level and tumor progression

We prospectively analyzed the circulating tumor burden in colorectal cancer patients using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) for carcinoembryonic antigen (CEA) and cytokeratin 19 (CK19 ). We distinguished the mRNA levels in peripheral blood between 33 patients and 26 healthy controls with reference to SK-BR-3 cell line. We found CEA-mRNA in 88% of patients and 92% of controls, and CK19 mRNA in 64% of patients and 19% of controls. Our CK19 mRNA assay was sufficiently sensitive to detect one SK-BR-3 cell among 10(6) normal blood cells. The upper limit of CK19 mRNA among controls was exceeded by 14 patients, and 12 patients (86%) developed systemic metastases/recurrence. Significantly elevated CK19 mRNA levels appeared to originate from circulating malignant cells (P<0.0001). Of relevance, the CK19 mRNA level increased with advancing Dukes' stage and correlated directly with the serum CEA level (P=0.016). CK19 mRNA quantification may prove valuable for cancer staging and disease monitoring.

Significant down-regulation of alpha-albumin in human hepatoma and its implication

The potential association of alpha-albumin (ALF) with hepatocellular carcinoma (HCC) was investigated. Expression of ALF was significantly reduced in HCC tumor tissue as compared with the paired peritumor tissue from 16 patients and in four HCC cell lines as compared with normal hepatocytes. ALF mRNA was also down-expressed in circulating HCC cells compared to circulating normal hepatocytes. The proliferation of Hep3B cells was inhibited by over-expression of ALF. Taken together, ALF is significantly down-regulated in HCC, and this might facilitate the proliferation of HCC. Thus, detection of ALF mRNA, in addition to that of alpha-fetoprotein (AFP) mRNA, might help to distinguish normal or malignant hepatocytes in peripheral blood.

Development of a multiple-marker RT-PCR assay for detection of micrometastases of hepatocellular carcinoma

We investigated the expression of several candidate gene markers: MAGE-1, MAGE-3, cytokeratin-20 (CK-20), and alpha-fetoprotein (AFP) in tumor tissue and blood specimens from patients with hepatocellular carcinoma to develop a multiple marker reverse transcriptase-polymerase chain reaction (RT-PCR) assay for detection of micrometastasis in circulation. In 24 tumor specimens, the positivity for MAGE-1, MAGE-3, AFP, and CK-20 genes was 71, 67, 88, and 79% respectively, and all specimens expressed at least one marker. Although AFP and CK-20 transcripts were also detected in corresponding noncancerous liver specimens, none of the 22 corresponding normal specimens or seven normal livers were positive for MAGE-1 or MAGE-3 transcripts. In addition, MAGE-1 and MAGE-3 gene transcripts were not detected in any peripheral blood specimens from 31 normal healthy volunteers. MAGE-1, MAGE-3, and AFP transcripts were detected in 9 (12.7%), 3 (4.8%), and 10 (15.9%) of 71 blood specimens from 11 hepatocellular carcinoma patients, respectively, while 19 specimens (26.8%) were positive for at least one marker. Our results indicate that a multimarker RT-PCR assay with cancer-specific markers such as MAGE-1 and MAGE-3 in combination with a liver-specific AFP marker may be a promising diagnostic tool for monitoring hepatocellular carcinoma patients with better sensitivity and specificity.

Aberrant p15 promoter methylation in adult and childhood acute leukemias of nearly all morphologic subtypes: potential prognostic implications

We prospectively analyzed p15 and p16 promoter methylation patterns using methylation-specific polymerase chain reaction (PCR) in patients with adult and childhood acute leukemias and studied the association of methylation patterns with chromosomal abnormalities and prognostic variables. In nearly all French-American-British leukemia subtypes, we found p15methylation in bone marrow or peripheral blood cells from 58% (46/79) of patients with acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), or acute biphenotypic leukemia (ABL). An identical alteration was detected in blood plasma from 11 of 12 of these patients (92%). We also demonstrated for the first time concomitant p16and p15 methylation in 22% (8/37) of adults with AML or ALL, exclusively in those with M2, M4, or L2 subtypes. According to cytogenetic data from 35 patients with ALL, AML, or ABL, 82% (14/17) of those with unmethylated p15 alleles had normal karyotypes or hyperdiploidies associated with a favorable prognosis. Conversely, 44% (8/18) of patients with p15 methylation had chromosomal translocations, inversions, or deletions, suggesting an interplay of these abnormalities with p15 methylation. As a prognostic marker for disease monitoring, p15 methylation appears to be more widely applicable than BCR-ABL, AF4-MLL, andAML1-ETO transcripts, which were detectable in only 8% (4/48) of patients by reverse transcriptase-PCR. Thirty-nine of 43 blood samples (91%) sequentially collected from 12 patients with AML, ALL, or ABL showed p15 methylation status in excellent concordance with morphologic disease stage. Early detection of p15methylation at apparent remission or its acquisition during follow-up may prove valuable for predicting relapse. Overall survival of patients with p15 methylation was notably shortened among 38 adults with AML and 12 adults with ALL. Aberrant p15 methylation may have important prognostic implications for clinical monitoring and risk assessment.

Role of alpha-fetoprotein in the diagnosis and management of hepatocellular carcinoma

Thirty-five years after its first description, alpha-fetoprotein (AFP) remains the gold standard by which other markers are judged. Serum levels above the reference range of 10 ng/mL occur in approximately 75% of cases of hepatocellular carcinoma (HCC). In individual patients, the serum AFP level behaves as if it reflects tumour mass. However, the specificity of AFP is relatively low because moderately raised levels are also found in some patients with uncomplicated chronic liver disease. Recently, tumour-specific AFP assays have been developed. These are based on the carbohydrate side-chains on the AFP molecule which exhibit characteristic differences in AFP of different origins. Monitoring response to treatment may often be more effectively carried out by serial estimation of AFP than by conventional imaging techniques. The relative specificity of AFP for HCC has also been employed to detect circulating HCC cells and to target gene therapy.