Both cell proliferation and apoptosis significantly predict shortened disease-free survival in hepatocellular carcinoma

Clearance of apoptotic cells by neutrophils in inflammation and cancer

When a cell dies of apoptosis, it is eliminated either by neighbouring cells or by attracted professional phagocytes. Although it was generally believed that neutrophils also have the ability to perform efferocytosis, their contribution to the clearance of apoptotic cells was considered less important compared with macrophages. Therefore, this ability of neutrophils remained unexplored for a long time. Over the past decade, it has been shown that during inflammation, neutrophils contribute significantly to the clearance of apoptotic neutrophils that accumulate in large numbers at the site of tissue damage. This "neutrophil cannibalism" is accompanied by inhibition of pro-inflammatory activities of these cells, such as respiratory burst and formation of neutrophil extracellular traps (NETs). Furthermore, efferocytosing neutrophils secrete anti-inflammatory mediators and mitogens including hepatocyte growth factor (HGF), fibroblast growth factor 2 (FGF2), vascular endothelial growth factors (VEGF), and transforming growth factor beta (TGFβ). Thus, efferocytosis by neutrophils is involved in resolution of inflammation. Recent research indicates that it plays also a role in cancer. Many different solid tumours contain aggregates of dead tumour cells that have undergone spontaneous apoptosis. Their extent correlates with poor clinical outcome in most cancer types. These clusters of apoptotic tumour cells are strongly infiltrated by tumour-associated neutrophils (TANs) that acquired an anti-inflammatory and pro-resolving polarization state. This review summarizes the potential consequences discussed in the current literature. Although the picture of the role of efferocytosis by neutrophils in inflammation and cancer is becoming clearer, many questions are still unexplored.

Isatin Counteracts Diethylnitrosamine/2-Acetylaminofluorene-Induced Hepatocarcinogenesis in Male Wistar Rats by Upregulating Anti-Inflammatory, Antioxidant, and Detoxification Pathways

Hepatocellular carcinoma (HCC) represents around 85% of all known types of liver cancers and is estimated to be the fifth most common cause of cancer-related death worldwide. The current study assessed the preventive efficacy of isatin on diethylnitrosamine (DENA)/2-acetylaminofluorene (2-AAF)-induced hepatocarcinogenesis in male Wistar rats and investigated the underlying cellular and molecular mechanisms. HCC was initiated by intraperitoneal injection of DENA (150 mg/kg/week) for two weeks, followed by oral 2-AAF (20 mg/kg) every other day for three successive weeks. Oral isatin or vehicle (control) was administered at 25 mg/kg for 20 weeks during and following HCC induction. Isatin ameliorated the deleterious effects of DENA/2-AAF on liver function as evidenced by reduced serum levels of AST, ALT, total bilirubin, albumin, and liver tumor biomarkers (CA19.9 and AFP) compared to control DENA/2-AAF-treated rats. Histopathological evaluations demonstrated that isatin-mediated protection against hepatocarcinogenesis was accompanied by a decline in hepatic lipid peroxidation, a marker of oxidative stress, and enhanced antioxidant capacity, as evidenced by increased glutathione and superoxide dismutase expression. Isatin treatment also upregulated expression of the major stress-response transcription factor Nrf2 and the detoxifying enzymes NAD(P)H quinine oxidoreductase and glutathione-S-transferase alpha 2 and downregulated expression of the proliferation marker Ki67. Moreover, isatin significantly reduced the DENA/2-AAF-induced decrease in hepatic expression of anti-apoptotic Bcl2 and the DENA/2-AAF-induced increases in pro-inflammatory and pro-apoptotic factors (TNF-α, NF-κB p50, NF-κB p65, p53, and caspase 3). Thus, it can be concluded that isatin may protect against chemically induced hepatocarcinogenesis by enhancing cellular antioxidant, anti-inflammatory, and detoxification mechanisms, in part through upregulation of the Nrf2 signaling pathway.

Debris-stimulated tumor growth: a Pandora's box?

Current cancer therapies aim at eradicating cancer cells from the body. However, killing cells generates cell “debris” which can promote tumor progression. Thus, therapy can be a double-edged sword. Specifically, injury and debris generated by cancer therapies, including chemotherapy, radiation, and surgery, may offset their benefit by promoting the secretion of pro-tumorigenic factors (e.g., eicosanoid-driven cytokines) that stimulate regrowth and metastasis of surviving cells. The debris produced by cytotoxic cancer therapy can also contribute to a tumor microenvironment that promotes tumor progression and recurrence. Although not well understood, several molecular mechanisms have been implicated in debris-stimulated tumor growth that we review here, such as the involvement of extracellular vesicles, exosomal miR-194-5p, Bax, Bak, Smac, HMGB1, cytokines, and caspase-3. We discuss the cases of pancreatic and other cancer types where debris promotes postoperative tumor recurrence and metastasis, thus offering a new opportunity to prevent cancer progression intrinsically linked to treatment by stimulating resolution of tumor-promoting debris.

Eicosanoid regulation of debris-stimulated metastasis

Cancer therapy, such as chemotherapy, induces tumor cell death (“debris”), which can stimulate metastasis. Chemotherapy-generated debris upregulates soluble epoxide hydrolase (sEH) and the prostaglandin E₂ receptor 4 (EP4), which triggers a macrophage-derived storm of proinflammatory and proangiogenic lipid autacoid and cytokine mediators. Although sEH inhibitors and EP4 antagonists are in clinical development for multiple inflammatory diseases, their combined role in cancer is unknown. Here, we show that the synergistic antitumor activity of sEH and EP4 inhibition suppresses hepato-pancreatic tumor growth, without overt toxicity, via macrophage phagocytosis of debris and counterregulation of a debris-stimulated cytokine storm. Thus, stimulating the resolution of inflammation via combined inhibition of sEH and EP4 may be an approach for preventing metastatic progression driven by cancer therapy.

Cancer therapy reduces tumor burden via tumor cell death (“debris”), which can accelerate tumor progression via the failure of inflammation resolution. Thus, there is an urgent need to develop treatment modalities that stimulate the clearance or resolution of inflammation-associated debris. Here, we demonstrate that chemotherapy-generated debris stimulates metastasis by up-regulating soluble epoxide hydrolase (sEH) and the prostaglandin E₂ receptor 4 (EP4). Therapy-induced tumor cell debris triggers a storm of proinflammatory and proangiogenic eicosanoid-driven cytokines. Thus, targeting a single eicosanoid or cytokine is unlikely to prevent chemotherapy-induced metastasis. Pharmacological abrogation of both sEH and EP4 eicosanoid pathways prevents hepato-pancreatic tumor growth and liver metastasis by promoting macrophage phagocytosis of debris and counterregulating a protumorigenic eicosanoid and cytokine storm. Therefore, stimulating the clearance of tumor cell debris via combined sEH and EP4 inhibition is an approach to prevent debris-stimulated metastasis and tumor growth.

Exploitation of Apoptotic Regulation in Cancer

Within an organism, environmental stresses can trigger cell death, particularly apoptotic cell death. Apoptotic cells, themselves, are potent regulators of their cellular environment, involved primarily in effecting homeostatic control. Tumors, especially, exist in a dynamic balance of cell proliferation and cell death. This special feature of the tumorous microenvironment—namely, the prominence and persistence of cell death—necessarily entails a magnification of the extrinsic, postmortem effects of dead cells. In both normal and malignant tissues, apoptotic regulation is exerted through immune as well as non-immune mechanisms. Apoptotic cells suppress the repertoire of immune reactivities, both by attenuating innate (especially inflammatory) responses and by abrogating adaptive responses. In addition, apoptotic cells modulate multiple vital cell activities, including survival, proliferation (cell number), and growth (cell size). While the microenvironment of the tumor may contribute to apoptosis, the postmortem effects of apoptotic cells feature prominently in the reciprocal acclimatization between the tumor and its environment. In much the same way that pathogens evade the host’s defenses through exploitation of key aspects of innate and adaptive immunity, cancer cells subvert several normal homeostatic processes, in particular wound healing and organ regeneration, to transform and overtake their environment. In understanding this subversion, it is crucial to view a tumor not simply as a clone of malignant cells, but rather as a complex and highly organized structure in which there exists a multidirectional flow of information between the cancer cells themselves and the multiple other cell types and extracellular matrix components of which the tumor is comprised. Apoptotic cells, therefore, have the unfortunate consequence of facilitating tumorigenesis and tumor survival.

Clinicopathologic Correlations of E-cadherin and Prrx-1 Expression Loss in Hepatocellular Carcinoma

Background

Developing predictive markers for hepatocellular carcinoma (HCC) is important, because many patients experience recurrence and metastasis. Epithelial to mesenchymal transition (EMT) is a developmental process that plays an important role during embryogenesis and also during cancer metastasis. Paired-related homeobox protein 1 (Prrx-1) is an EMT inducer that has recently been introduced, and its prognostic significance in HCC is largely unknown.

Methods

Tissue microarray was constructed using surgically resected primary HCCs from 244 cases. Immunohistochemical staining of E-cadherin and Prrx-1 was performed. The correlation between E-cadherin loss and Prrx-1 expression, as well as other clinicopathologic factors, was evaluated.

Results

E-cadherin expression was decreased in 96 cases (39.4%). Loss of E-cadherin correlated with a higher recurrence rate (p < .001) but was not correlated with patient’s survival. Thirty-two cases (13.3%) showed at least focal nuclear Prrx-1 immunoreactivity while all non-neoplastic livers (n = 22) were negative. Prrx-1 expression was not associated with E-cadherin loss, survival or recurrence rates, pathologic factors, or the Ki-67 labeling index. Twenty tumors that were positive for E-cadherin and Prrx-1 had significantly higher nuclear grades than the rest of the cohort (p = .037). In Cox proportional hazard models, E-cadherin loss and large vessel invasion were independent prognostic factors for shorter disease-free survival. Cirrhosis and high Ki-67 index (> 40%) were independent prognostic factors for shorter overall survival.

Conclusions

Prrx-1 was expressed in small portions of HCCs but not in normal livers. Additional studies with a large number of Prrx-1-positive cases are required to confirm the results of this study.

Clinical and biological significance of transcription termination factor, RNA polymerase I in human liver hepatocellular carcinoma

Recent studies have indicated that increased ribosomal activity contributes to cancer progression. Transcription termination factor, RNA polymerase I (TTF1) acts as a transcription factor for RNA polymerase I. However, the role which TTF1 plays in cancer progression still remains unknown. The present study aimed to determine whether TTF1 plays a critical role in the progression of human liver hepatocellular carcinoma (HCC). In the present study, quantitative real-time reverse transcription polymerase chain reaction was conducted to evaluate TTF1 mRNA expression in 60 HCC tissue samples in order to determine the clinicopathological significance of TTF1. To investigate whether the expression levels of TTF1 were associated known gene signatures which represented ribosomal activity, we applied gene set enrichment analysis (GSEA) to HCC cases in The Cancer Genome Atlas (TCGA) a. We also performed in vitro proliferation assays using TTF1‑overexpressing HCC cells. TTF1 expression was significantly higher in HCC tumor tissues than in adjacent liver tissues (P<0.001). The overall survival (OS) of patients with high TTF1 expression levels was significantly shorter than that of patients with low TTF1 expression (P=0.027). Multivariate analysis indicated that TTF1 expression was an independent prognostic factor for OS (P=0.020). GSEA revealed significant associations between TTF1 expression and gene sets involved in ribosomal function. In vitro, cell proliferation and rRNA transcription were significantly promoted by overexpression of TTF1 in the HCC cell lines HuH-7 and HepG2. From these results, it was suggested that TTF1 participate in poor prognoses and play a role in tumor cell growth in HCC, possibly by upregulating ribosomal activity. In conclusion, we first propose that TTF1 may be a novel biomarker and therapeutic target in HCC. Increased expression of TTF1 was significantly associated with poor prognosis in two independent sets of HCC cases. Furthermore, in vitro experiments provided an explanation for clinical data showing that overexpression of TTF1 contributed to the proliferation of cancer cells.

Clinicopathological and prognostic significance of high Ki-67 labeling index in hepatocellular carcinoma patients: a meta-analysis

BACKGROUND

The relationship between Ki-67 labeling index (LI) and clinical outcome in hepatocellular carcinoma (HCC) has been investigated by various studies, but no consistent result has been concluded. To define the prognostic significance of Ki-67 LI in patients with HCC, we performed a meta-analysis.

METHODS

We searched for literatures in the following databases: PubMed, ISI Web of Science, EMBASE, Cochrane Central Register of Controlled Trials, Science Direct, Wiley Online Library, Google Scholar, China National Knowledge Infrastructure (CNKI), Chinese VIP and WanFang Databases. Our search ended on April 6th, 2015. Data were extracted from eligible studies and the correlation between Ki-67 LI and clinicopathological features of HCC was analyzed and pooled hazard ratios (HRs) for eligible studies were calculated by STATA 11.0 (STATA Corp., College, TX).

RESULTS

In total, 54 studies involving 4996 patients were included in the current meta-analysis. The meta-analysis provided evidence that high Ki-67 LI was closely associated with histological grade, tumor size, number of tumor nodes, the status of metastasis, cirrhosis and vein invasion in HCC patients. The pooled HRs showed that high Ki-67 LI had an unfavorable impact on disease-free survival (DFS) (HR=1.626, 95% confidence interval (CI): 1.364-1.939, P<0.001), relapse-free survival (RFS) (HR=1.820, 95% CI: 1.215-2.725, P=0.004) and overall survival (OS) (HR=1.170, 95% CI: 1.102-1.243, P<0.001), respectively. Additionally, subgroup analysis indicated that high Ki-67 LI was related to poorer DFS, RFS and OS independent of regions, treatment strategies or statistical methods, except that no statistical significance was found on RFS (HR=2.413, 95% CI: 0.523-11.142, P=0.259) and OS (HR=1.998, 95% CI: 0.797-5.009, P=0.14) in patients with liver transplantation.

CONCLUSIONS

Our meta-analysis suggests that higher Ki-67 LI confers a fast progression and poor prognosis for HCC patients.

Management of hepatocellular carcinoma: Predictive value of immunohistochemical markers for postoperative survival

Hepatocellular carcinoma (HCC) accounts for over 90% of all primary liver cancers. With an ever increasing incidence trend year by year, it has become the third most common cause of death from cancer worldwide. Hepatic resection is generally considered to be one of the most effective therapies for HCC patients, however, there is a high risk of recurrence in postoperative HCC. In clinical practice, there exists an urgent need for valid prognostic markers to identify patients with prognosis, hence the importance of studies on prognostic markers in improving the prediction of HCC prognosis. This review focuses on the most promising immunohistochemical prognostic markers in predicting the postoperative survival of HCC patients.

Breast cancer metastasis suppressor 1 regulates hepatocellular carcinoma cell apoptosis via suppressing osteopontin expression

Breast cancer metastasis suppressor 1 (BRMS1) was originally identified as an active metastasis suppressor in human breast cancer. Loss of BRMS1 expression correlates with tumor progression, and BRMS1 suppresses several steps required for tumor metastasis. However, the role of BRMS1 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that the expression level of BRMS1 was significantly down-regulated in HCC tissues. Expression of BRMS1 in SK-Hep1 cells did not affect cell growth under normal culture conditions, but sensitized cells to apoptosis induced by serum deprivation or anoikis. Consistently, knockdown of endogenous BRMS1 expression in Hep3B cells suppressed cell apoptosis. We identified that BRMS1 suppresses osteopontin (OPN) expression in HCC cells and that there is a negative correlation between BRMS1 and OPN mRNA expression in HCC tissues. Moreover, knockdown of endogenous OPN expression reversed the anti-apoptosis effect achieved by knockdown of BRMS1. Taken together, our results show that BRMS1 sensitizes HCC cells to apoptosis through suppressing OPN expression, suggesting a potential role of BRMS1 in regulating HCC apoptosis and metastasis.

IGFBP7 downregulation is associated with tumor progression and clinical outcome in hepatocellular carcinoma

Insulin-like growth factor-binding protein 7 (IGFBP7) functions in several cellular processes including proliferation, senescence and apoptosis. This study analyzed IGFBP7 function in hepatocellular carcinoma (HCC) cells by gene manipulation and investigated the prognostic significance of IGFBP7 expression in clinical HCC samples. In this study, we investigated changes in malignant potential such as cell growth and invasiveness in an HCC cell line, PLC/PRF/5, after transfection with shRNA against IGFBP7. The extent of apoptosis and cell cycle progression were examined after the transfection. The correlation between immunohistochemically determined IGFBP7 expression and long-term postoperative prognosis after curative resection was also investigated in clinical HCC specimens obtained from 104 patients. PLC/PRF/5 cells transfected with shRNA against IGFBP7 showed significantly more rapid growth and stronger invasiveness than control cells. Annexin V assays showed that the IGFBP7-depleted cells were significantly more resistant to apoptosis than the control cells, and showed decreased expression of cleaved caspase-3 and PARP. Cell cycle progression was more rapid in the IGFBP7-suppressed cells. In clinical HCC specimens, IGFBP7 expression was judged as positive in 67 patients (64.4%) and negative in the remaining 37 patients (35.6%). The IGFBP7 downregulation correlated significantly with poor postoperative prognosis, and IGFBP7 status was identified as an independent significant prognostic factor. Our results indicated that IGFBP7 expression correlated significantly with the malignant potential in HCC cells, suggesting that the expression could be a useful prognostic marker for HCC.

Reduction of 15-hydroxyprostaglandin dehydrogenase expression is an independent predictor of poor survival associated with enhanced cell proliferation in gastric adenocarcinoma

Prostaglandin (PG) E(2) promotes gastrointestinal carcinogenesis and tumor progression. We determined the correlations between pattern of expression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a catabolic enzyme for biological inactivation of PGE(2), in gastric adenocarcinoma and various clinicopathological factors and patient outcome in an attempt to elucidate its biological significance. In 35 of 71 cases of gastric adenocarcinoma, expression of 15-PGDH protein was reduced in tumor tissues. Multivariate analysis revealed reduction of 15-PGDH expression to be an independent predictor of poor survival. The proportion of Ki67-positive cells in 15-PGDH-negative adenocarcinoma was higher than that in 15-PGDH-positive adenocarcinoma. No differences were found in clinicopathological parameters between patients with cyclooxygenase-2 (COX-2)-positive tumors and those with COX-2 negative tumors. In an in vitro study, use of specific siRNA to silence 15-PGDH or a specific inhibitor of 15-PGDH enhanced cell proliferation in the gastric cancer cell line AGS, which expresses 15-PGDH. These findings suggest that reduction of 15-PGDH is an independent predictor of poor survival associated with enhancement of cell proliferation in gastric adenocarcinoma.

Assessment of the Proliferative Marker Ki-67 and p53 Protein Expression in HBV- and HCV-related Hepatocellular Carcinoma Cases in Egypt

BACKGROUND

Chronic HBV and HCV infections are the major risk factors for the development of HCC through a multistep pathway that involves viral and non-viral dependent pathophysiological steps. Hepatic expression of the nuclear proliferative marker ki-67 and the p53 oncoprotein were found to be associated with poor outcome. So, the present study was done to evaluate the changes in expression of Ki-67 and p53 oncoprotein, and to determine p53 gene mutation in HBV/HCV-related HCC Egyptian patients.

METHODS

Eight HBV-and 22 HCV-positive HCC cases have been examined for the presence of p53 mutation by immunohistochemistry (IHC) and single-strand conformation polymorphism (SSCP), followed by direct DNA sequencing. HCV were genotyped by LiPA-II.

RESULTS

Our results have shown that the proliferative marker ki-67 LI and p53 were highly expressed and significantly related to tumor grade in the Egyptian HCC cases (p<0.05). Also, p53 mutation was found in 16 HCC cases by IHC and in 14 HCC cases by SSCP, only 11 patients showed p53 mutation by sequencing. The highest mutation rate was scored for exon 7 (7 mutations) at codon 249; 4 out of 8 (50%) of HBV-related HCC cases and 3 out of 22 (13.6%) of HCV-related HCC cases, followed by exon 5 (3 mutations) at codons 133, 146, 176 in HCV-related HCC cases, then exon 8 at codon 275 in HCV-related HCC cases. The concordance between the IHC and sequencing analysis was 69%.

CONCLUSION

The present study demonstrates the association between the proliferative marker ki-67 and p53 expression with the tumor grade of Egyptian HBV/HCV-related HCC cases. Our results also support the hypothesis that p53 mutations are rather a late event in the carcinogenesis. Also, they suggest that the final steps of hepatocarcinogenesis are common and independent of the aetiology of the viral infection.

Cell proliferation and hepatocarcinogenesis in rat initiated by diethylnitrosamine and promoted by phenobarbital: Potential roles of early DNA damage and liver metallothionein expression

Cell proliferation plays an important role in multistage chemical carcinogenesis. Again, several reports demonstrated that upregulation of metallothionein (MT) expression is associated with increased cell proliferation that may contribute to the pathogenesis of preneoplastic phenotype to frank malignancy. In this study, we evaluated the roles of early DNA damage, altered expressions of liver MT and Ki-67 nuclear antigen, and altered hepatic levels of zinc (Zn) and copper (Cu) on cell proliferation and the progression of hepatocarcinogenesis through premalignant, late premalignant and malignant transformation phases in male Sprague-Dawley rats. We have further studied the association between MT expression and cell proliferation in hepatocarcinogenesis. There was substantial induction of DNA single-strand breaks (SSBs) (P<0.001) and development of hepatocellular premalignant lesions along with significant decrease in hepatic levels of Zn and increase in Cu content following a single, necrogenic, intraperitoneal (i.p.) injection (200 mg/Kg body weight) of diethylnitrosamine (DEN) at week 4 of the experimental protocol. Moreover, DEN+phenobarbital (PB)-treatment significantly elevated MT-, Ki-67-, and BrdU-immunoexpressions along with their immunolabeling indices. Furthermore, positive correlations between MT- and Ki-67- labeling (P=0.0006) at various time intervals, as well as, between MT immunoreactivity and 5'-bromo-2'-deoxyuridine-labeling index (BrdU-LI) (P=0.0007) indicate that, MT expression might be associated with Ki-67 expression and cell proliferation thereby. The study suggests that DEN treatment may lead to alteration of Zn and Cu levels resulting in early DNA damage along with elevation of MT expression that may ultimately lead to hepatic cell proliferation. The results thus provide evidence in support of the role of MT as a potential positive regulator of cell growth during the early stages of hepatocellular transformation in rats.

The expression of transforming growth factor-alpha in cirrhosis, dysplastic nodules, and hepatocellular carcinoma: an immunohistochemical study of 70 cases

The emergence of hepatocellular carcinoma (HCC) is thought to be a stepwise process, with high-grade dysplastic nodules (HGDN) representing premalignant lesions arising in a background of cirrhosis. Earlier studies have revealed altered expression of transforming growth factor-alpha (TGF-alpha) (a mitogen capable of inducing hepatocarcinogenesis in mice) in HCC and its surrounding parenchyma. DNA topoisomerase II-alpha (Topo II-alpha) is a nuclear protein targeted by several chemotherapeutic agents and is overexpressed in HCC. The expression of both TGF-alpha and Topo II-alpha in putative preneoplastic hepatocytic lesions, however, has not been extensively studied. We examined the patterns of TGF-alpha and Topo II-alpha expression in noncirrhotic liver, liver cirrhosis, low-grade dysplastic nodules (LGDN), HGDN, and HCC to define the possible relationships of these markers to tumor progression. Paraffin sections from formalin-fixed material were immunostained with antibodies against TGF-alpha, Topo II-alpha, and Ki-67. Forty-six HCC, 17 HGDN, and 12 low-grade dysplastic nodules were identified in 52 cirrhotic livers from explanted or resected specimens. Nuclear staining for Ki-67 and Topo II-alpha was significantly increased in the progression from cirrhosis, through HGDN, to HCC, whereas the scores for TGF-alpha in these lesions showed an inverse relationship. In comparison with 18 HCC arising in noncirrhotic livers, the expression of TGF-alpha is significantly stronger in cirrhotic liver than in noncirrhotic parenchyma and its expression is also stronger in HCC arising in cirrhosis than in HCC arising in noncirrhotic parenchyma. The increased expression of Topo II-alpha and Ki-67 from HGDN to HCC, when compared with cirrhosis, suggests that HGDN is a precursor lesion in hepatocarcinogenesis. The inverse relationship between these proliferative markers and TGF-alpha expression in these lesions and stronger expression of TGF-alpha in HCC arising in cirrhosis suggest that TGF-alpha may play an important role in the early events of liver carcinogenesis.

Prognostic molecular markers in hepatocellular carcinoma: a systematic review

Hepatocellular carcinoma (HCC) is the fifth commonest malignancy worldwide and its incidence is rising. Surgery, including transplantation, remains the only potentially curative modality for HCC, yet recurrence rates are high and long-term survival poor. The ability to predict individual recurrence risk and subsequently prognosis would help guide surgical and chemotherapeutic treatment. As understanding of hepatocarcinogenesis has increased, the myriad of genetic and molecular events that drive the hepatocarcinogenic disease process, including angiogenesis, invasion and metastasis, have been identified. This systematic review examines the evidence from published manuscripts reporting the prognostic potential of molecular biomarkers in hepatocellular carcinoma. In summary, a number of molecular biomarkers with prognostic significance have been identified in hepatocellular carcinoma. Not only might these molecules allow more accurate prediction of prognosis for patients with HCC, but they may also provide targets for potential therapeutic agents.

Hepatic progenitor cells in human liver tumor development

In recent years, the results of several studies suggest that human liver tumors can be derived from hepatic progenitor cells rather than from mature cell types. The available data indeed strongly suggest that most combined hepatocellular-cholangiocarcinomas arise from hepatic progenitor cells that retained their potential to differentiate into the hepatocytic and biliary lineages. Hepatic progenitor cells could also be the basis for some hepatocellular carcinomas and hepatocellular adenomas, although it is very difficult to determine the origin of an individual hepatocellular carcinoma. There is currently not enough data to make statements regarding a hepatic progenitor cell origin of cholangiocarcinoma. The presence of hepatic progenitor cell markers and the presence and extent of the cholangiocellular component are factors that are related to the prognosis of hepatocellular carcinomas and combined hepatocellular-cholangiocarcinomas, respectively.

Opportunities for targeted therapies in hepatocellular carcinoma

Hepatocellular cancer (HCC) is the fifth most common solid tumor worldwide, accounting for 500,000 new cases annually. Although less common in the United States, HCC is expected to increase in incidence over the next two decades largely because of the prevalence of hepatitis C virus infection. A majority of patients present with advanced disease and are not candidates for liver transplantation, surgical resection, or regional therapy. In 60% to 80% of patients with HCC, treatment is complicated by underlying liver cirrhosis and hepatic dysfunction. Systemic treatments are minimally effective, can have significant toxicity, and have not been shown to improve patient survival. New approaches targeting molecular abnormalities specific to HCC are needed to improve patient outcome. This review summarizes the state of knowledge of those key aspects of the molecular pathogenesis of HCC that may represent rational therapeutic targets in this disease. Relevant preclinical and clinical information on novel compounds directed toward abnormalities in HCC is reviewed.

Hepatic expression of the proliferative marker Ki-67 and p53 protein in HBV or HCV cirrhosis in relation to dysplastic liver cell changes and hepatocellular carcinoma

To evaluate hepatic expression of the nuclear proliferative marker Ki-67 and the p53 oncoprotein in hepatitis B virus (HBV)/HCV cirrhosis in relation to dysplastic liver cell changes and hepatocellular carcinoma (HCC). We studied needle liver biopsies from 107 patients with cirrhosis and no HCC (52 HBV, 55 HCV) who had been assessed for protocol studies, and 57 cirrhotic patients with HCC (40 HBV, 17 HCV). We evaluated small and large cell dysplastic changes along with the expression of Ki-67 and p53 by immunohistochemistry. The labelling index (LI) was defined as the proportion (%) of positive-stained nuclei of the 500 measured. Large and small cell dysplastic changes were observed in 12 and 9% of specimens respectively. Only small cell changes were associated with Ki-67 expression. Ki-67 LI was 5.50 +/- 5.7 in cirrhosis (13.90 +/- 3.84 in those with small cell dysplastic changes vs 4.64 +/- 4.98 in those without, P < 0.01), 10.2 +/- 5.95 in cirrhosis with HCC (P < 0.05) and 18.56 +/- 10 in HCC (P < 0.01). Neither the presence of small cell dysplastic changes nor the expression of Ki-67 was related to severity or aetiology of cirrhosis. Expression of p53 was observed in 30% of the non-tumorous and in 53% of the neoplastic tissue obtained from patients with HCC, with no differences between HCV and HBV. Ki-67 and p53 expression was associated with the tumour grade (P < 0.001). Our observations clearly demonstrate the association between the proliferation activity and the morphological changes in the cirrhotic liver from the non-dysplastic to dysplastic lesion to HCC. They also support the hypothesis that p53 alterations are a rather late event in carcinogenesis and related to HCC grade. And finally, they suggest that the final steps of hepatocarcinogenesis are common and independent of the aetiology of the chronic viral infection.

Vanadium induces apoptosis and modulates the expressions of metallothionein, Ki-67 nuclear antigen, and p53 during 2-acetylaminofluorene-induced rat liver preneoplasia

Our previous studies have shown that vanadium, a dietary micronutrient, has an inhibitory effect against experimentally induced rat hepatocarcinogenesis. In this study, we evaluated the role of vanadium on some potential protein expression markers of carcinogenesis, such as metallothionein (MT), an intracellular metal-binding protein linked with cell proliferation and apoptosis, Ki-67 nuclear antigen, and p53 tumor suppressor during 2-acetylaminofluorene (2-AAF)-induced (0.05% in basal diet) rat liver preneoplasia. In a short-term regimen, supplementation of vanadium at a dose of 0.5 ppm effectively suppressed the formation of DNA 'comets' (29.55%; P < 0.02), thereby indicating its nongenotoxicity at this particular dose. Vanadium administration throughout the study reduced relative liver weight (RLW), nodular incidence (57.15%), total number, and multiplicity (48.45%) with restoration of hepatic zinc (Zn), magnesium (Mg), selenium (Se), copper (Cu), iron (Fe), and calcium (Ca) contents when compared to the carcinogen control. Moreover, treatment with vanadium significantly abated the expressions of MT and Ki-67, studied at four sequential time points. An increased immunopositivity of p53 protein (1.03 +/- 0.23%; P < 0.02) was found in vanadium-treated rat liver with an elevated apoptotic-labeling index (AI; P < 0.001) as documented by TUNEL assay. Furthermore, a positive correlation between MT expression and Ki-67 labeling along with a strong negative correlation between MT immunoreactivity and AI (r = -0.9000, P = 0.0004 at week 24) at various time intervals suggest that, vanadium-mediated suppression of MT and Ki-67 expressions may be associated with induction of apoptosis. The results thus provide evidence for the first time in support of the potential role of vanadium on induction of p53 and apoptosis with concurrent suppression of MT and Ki-67 in order to have an understanding, in part, of the chemopreventive mechanism of this trace element in limiting neoplastic transformation in a defined model of experimental rat hepatocarcinogenesis.

Construction and clinical significance of a predictive system for prognosis of hepatocellular carcinoma

AIM: The aims of this study were to explore individualized treatment method for hepatocellular carcinoma (HCC) patients whose maximum tumor size was less than 5 cm to improve prognosis and survival quality.

METHODS: Thirty cases of primary HCC patients undergoing tumor resection were retrospectively analyzed (resection group). All the tumors were proved as primary HCC with pathologic examination. The patients were divided into two groups according to follow-up results: group A, with tumor recurrence within 1 year after resection; group B, without tumor recurrence within 1 year. Immunohist-ochemical stainings were performed using 11 kinds of monoclonal antibodies (AFP, c-erbB2, c-met, c-myc, HBsAg, HCV, Ki-67, MMP-2, nm23-H1, P53, and VEGF), and expressing intensities were quantitatively analyzed. Regression equation using factors affecting prognosis of HCC was constructed with binary logistic method. HCC patients undergoing percutaneous microwave coagulation therapy (PMCT) were also retrospectively analyzed (PMCT group). Immunohistochemical stainings of tumor biopsy samples were performed with molecules related to HCC prognosis, staining intensities were quantitatively analyzed, coincidence rate of prediction was calculated.

RESULTS: In resection group, the expressing intensities of c-myc, Ki-67, MMP-2 and VEGF in cancer tissue in group A were significantly higher than those in group B (t = 2.97, P = 0.01; t = 2.42, P = 0.03<0.05; t = 2.57, P = 0.02<0.05; t = 3.43, P = 0.004<0.01, respectively); the expressing intensities of 11 kinds of detected molecules in para-cancer tissue in groups A and B were not significantly different (P>0.05). The regression equation predicting prognosis of HCC is as follows: P(1) = 1/[1+e^{-(3.663-0.412mycc-2.187Ki-67c-0.397vegfc)}]. It demonstrates that prognosis of HCC in resection group was related with c-myc, Ki-67 and VEGF expressing intensity in cancer tissue. In PMCT group, the expressing intensities of c-myc, Ki-67 and VEGF in cancer tissue in group A were significantly higher than those in group B (t = 4.57, P = 0.000<0.01; t = 2.08, P = 0.04<0.05; t = 2.38, P = 0.02<0.05, respectively); the expressing intensities of c-myc, Ki-67 and VEGF in para-cancer tissue in groups A and B were not significantly different (P>0.05). The coincidence rate of patients undergoing PMCT in group A was 88.00% (22/25), in group B 68.75% (11/16), the total coincidence rate was 80.49% (33/41).

CONCLUSION: The regression equation is accurate and feasible and could be used for predicting prognosis of HCC, it helps to select treatment method (resection or PMCT) for HCC patients to realize individualized treatment to improve prognosis.

Tumour staging, morphology and p53 overexpression concur in predicting survival in hepatocellular carcinoma

BACKGROUND/AIMS

The prognosis of hepatocellular carcinoma (HCC) on cirrhosis is hard to predict as it depends on tumour stage, underlying liver disease, type of treatment and, possibly, biological factors of the tumour itself.

METHODS

We prospectively evaluated the survival of 91 consecutive patients with HCC on cirrhosis, diagnosed between January 1998 and December 1999. Clinical features and histological/biological aspects, including histotype, grade, p53 overexpression, cytoproliferation and apoptotic markers were analysed.

RESULTS

Child-Pugh (P = 0.01), Okuda (P < 0.0001), Cancer of the Liver Italian Program (CLIP) staging (P < 0.0001) and type of treatment (P = 0.0001) were significantly related to survival. In the Cox model, CLIP staging was included as independent predictor of survival at step 1 (P < 0.0001) with Okuda at step 2 (P = 0.013). Amongst the biological factors, p53 overexpression and histotype were significantly related with survival (P = 0.0044 and 0.017 respectively). When clinical and biological variables were examined together in the Cox model, CLIP and Okuda were confirmed as being statistically related with survival (P < 0.0001 and =0.012) followed by histotype and p53 overexpression (P = 0.019 and 0.02).

CONCLUSIONS

CLIP, Okuda, histotype and p53 overexpression are the strongest predictors of survival in this series of patients. These data confirm that staging of the tumour and underlying liver disease are strictly related to prognosis but support the concurrent role of clinical and biological factors in upgrading our capacity of predicting the fate of HCC patients.

Differential expression of antioxidant enzymes in various hepatocellular carcinoma cell lines

Recent evidence suggests that reactive oxygen species (ROS) play an important role in the pathogenesis of various illnesses, and the ROS and antioxidant enzymes are highly associated with cell differentiation and diseases. In this study, we tested the hypothesis that specific antioxidant enzymes are differentially expressed in hepatocellular carcinoma (HCC) cell lines with various degrees of differentiation. We compared the expression of several antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GRx), and glutathione peroxidase (GPx) in five HCC cell lines with well (Hep G2 and Hep 3B) or poor (HA22T/VGH, HA55T/VGH, and SK-Hep-1) differentiation. Our results showed that both well-differentiated HCC cell lines expressed extremely higher CAT and GRx enzyme activities than all three poorly differentiated ones. Moreover, the protein and mRNA levels of CAT were much higher in two well-differentiated HCC cell lines than in all three poorly differentiated ones. Both well-differentiated HCC cell lines also showed a higher protein or mRNA expression of Cu/ZnSOD and MnSOD than three poorly differentiated ones. Our results demonstrate that specific antioxidant enzymes (especially, CAT and GRx) are differentially expressed in HCC cell lines with well or poor differentiation. These findings suggest that CAT and GRx are two potential differentiation markers for HCC.

Growth index, assessed with Ki-67 and ssDNA labeling; a significant prognosticator for patients undergoing curative resection for hepatocellular carcinoma

BACKGROUND AND OBJECTIVES

The aggressiveness and greater malignant potential of cancers are characterized by several biological phenomena such as accelerated growth invasiveness, and the ability to form distant metastasis. Thus, knowledge of such biological difference may be a more accurate prognosticator for cancer patients. Tumor growth depends on the degree of imbalance between cell production and loss. This study aimed to clarify a possible role for the modified prognosticator, growth index (GI); defined as the difference between Ki-67 (%) and single-stranded DNA (ssDNA) (%) labeling indices, in patients undergoing curative resection for hepatocellular carcinoma (HCC).

METHODS

Tissue specimens were obtained from 40 HCC patients who underwent curative surgery. Immunohistochemical staining was performed using the avidin-biotin-peroxidase-complex method.

RESULTS

The GI in HCC ranged from -1.90% to 28.65%, median 3.73. GI was related to histologic grade, intrahepatic metastasis, and pathologic T stage. Cumulative survival was poorer in patients with higher GI (> or = median value). Multivariate analysis demonstrated that GI is an independent prognosticator along with vascular invasion and intrahepatic metastasis.

CONCLUSIONS

The higher GI values were significantly associated with histologic aggressive features of HCCs, and GI was a significant independent prognosticator in HCC patients after curative resection.

Prognostic significance of Bcl-xL in human hepatocellular carcinoma

BACKGROUND

Proliferation and apoptosis of liver cancer cells are closely related phenomena. We investigated the correlation between overexpression of Bcl-xL, an anti-apoptosis-related protein of the Bcl-2 family, and the clinical course of hepatocellular carcinoma (HCC).

METHODS

Specimens from 7 HCC patients were used for Western blotting and immunoelectron microscopy tests. Samples from 33 HCC patients who had undergone hepatectomies were used for immunohistochemical staining. The degrees of expression of Bcl-xL and Ki-67, as an index of HCC mitosis severity, were each classified into 2 groups.

RESULTS

With the use of Western blot analysis, enhanced immunoreactivity of Bcl-xL was found in cancerous specimens. Bcl-xL overexpression was found in cancer specimens in 21 of 33 patients (63.6%). The overall survival (P=.019) and disease-free survival (P=.030) rates of the group overexpressing Bcl-xL were definitely poorer. The Ki-67 higher labeling index LI > 10) group had a poorer survival rate (P=.016). There were significant correlations between Bcl-xL and overall survival and disease-free survival. Multivariate analyses revealed that Bcl-xL, tumor size, histologic portal invasion, and histologic metastatic foci were independent prognostic factors for overall survival and disease-free survival.

CONCLUSIONS

These results showed Bcl-xL in HCC specimens, suggesting that Bcl-xL was a significant prognostic factor for disease progression in human HCC.

Expression of 8-hydroxy-2'-deoxyguanosine in chronic liver disease and hepatocellular carcinoma

Reactive oxygen species may be involved in the progression of chronic liver disease and the occurrence of hepatocellular carcinoma (HCC). To clarify whether clinicopathological findings in liver diseases are related to oxidative DNA damage, hepatic expression of the 8-hydroxy-2'-deoxyguanosine (8-OHdG) was examined in 75 liver disease patients, which included 32 chronic hepatitis (CH), 13 liver cirrhosis (LC) and 30 HCC patients. The CH patients had higher 8-OHdG-positive hepatocytes than LC (P < 0.05). In CH and LC, the number of 8-OHdG-positive hepatocytes was correlated with alanine aminotransferase and asparate aminotransferase (P < 0.01 and P < 0.05, respectively). Of 30 HCC cases, 25 cases (83%) showed stronger immunoreactivity than non-cancerous counterparts. The patients with poorly differentiated HCC had a larger tumor size and higher levels of AFP, and exhibited higher labeling indices of PCNA-, TUNEL- and 8-OHdG-positive cells than those with well and moderately differentiated HCC. Our findings suggest that oxidative DNA damage is increased in association with necroinflammation in chronic liver disease and determination of 8-OHdG is useful in assessing high-grade malignancy in HCC.

Induction of apoptosis in mouse liver adenoma and carcinoma in vivo by transforming growth factor-beta1

PURPOSE

In the liver, transforming growth factor beta-1 (TGF-beta1) constitutes a major negative growth regulating factor involved in the control of cell numbers; failure of this control mechanism has been associated with the development of liver cancer. Since no reports on the in vivo effects of exogenously administered TGF-beta1 on apoptosis in liver tumors have been published yet, we studied hepatocyte sensitivity to the proapoptotic action of TGF-beta1 in stages of chemically induced mouse liver carcinogenesis.

METHODS

Mouse liver carcinogenesis was initiated by a single dose of N-nitrosodiethylamine (NDEA, 90 mg/kg b.w., i.p.) to 5-week-old B6C3F1 mice. After 2 weeks, mice received either standard diet or a diet containing phenobarbital (PB, 90 mg/kg b.w) for 85 weeks. Four hours before being killed mice received a single dose of TGF-beta1 (56 microg or 200 microg TGF-beta1/kg of b.w., injected into the tail vein). Quantitative histological analysis of mitosis and apoptosis in normal liver tissue (NL), putative preneoplastic foci (PPF), hepatocellular adenoma (HCA), and hepatocellular carcinoma (HCC) was performed on H&E-stained liver sections.

RESULTS

In NDEA and NDEA + PB-treated mice, NL exhibited a very low incidence of apoptosis and mitosis, which increased in HCA and HCC. In the lesions apoptoses ranged between 0.03 and 0.6%. Two hundred micrograms of TGF-beta1/kg stimulated apoptoses in NL as well as in neoplastic lesions (significant increase in NL, HCA, and HCC); the most pronounced proapoptotic action of TGF-ss1 was observed in lesions of NDEA+PB pretreated mice (about 1.7%). Fifty-six microg TGF-beta1/kg had no detectable effect on apoptosis.

CONCLUSION

These observations indicate that during chemically induced liver carcinogenesis in B6C3F1 mice basal rates of apoptoses in adenoma and carcinoma are higher than in normal liver and can be further increased by a proapoptotic cytokine.

Hormone receptors in non-malignant meningiomas correlate with apoptosis, cell proliferation and recurrence-free survival

AIMS

A retrospective immunohistochemical and statistical analysis of patients with non-malignant meningiomas was undertaken to determine the correlation of steroid hormone receptor status with apoptosis, tumour cell proliferation, clinicopathological characteristics and prediction of recurrence.

METHODS AND RESULTS

Paraffin sections from 51 primary intracranial totally resected benign and atypical meningiomas were immunohistochemically evaluated for the expression of progesterone (PR), oestrogen (ER) and androgen (AR) receptors, apoptotic rate, Bcl-2, p53 and Ki67 antigens. In addition to the above parameters, the mitotic index and the patients' clinicopathological data were statistically correlated and entered in a recurrence-free survival analysis. A high level of apoptotic cell death was associated with loss of PR expression by logistic regression analysis (P = 0.016). An inverse correlation existed between the mitotic index and PR counts (P = 0.009), while high Ki67 values correlated with increased ARs (P = 0.041). Atypical meningiomas had a lower ER staining score (P = 0.036). Multivariate analysis indicated that the absence of PR and large tumour size were significant factors for shorter disease-free intervals.

CONCLUSIONS

The results suggest that ER expression is lost or reduced in atypical meningiomas, whereas loss of PR expression is an indicator of increased apoptosis and early recurrence. PRs and ARs may also influence tumour cell proliferation.

Cellular retinol-binding protein-1 in hepatocellular carcinoma correlates with beta-catenin, Ki-67 index, and patient survival

The cellular retinol-binding protein-1 (CRBP-1) plays a key role in the esterification and intercellular transfer of retinol. By in situ hybridization, immunohistochemistry, and confocal laser scanning microscopy (CLSM), we show that, in normal liver, CRBP-1 is strongly expressed in the cytoplasm of hepatic stellate cells (HSCs) and myofibroblasts (MFs) with only low CRBP-1 levels in hepatocytes. By contrast, in 196 hepatocellular carcinoma (HCC) specimens CRBP-1 expression in MFs was down-regulated in 83%. Patients with high CRBP-1 expression in MFs had a significantly higher 2-year survival as compared with patients with low CRBP-1 expression (52% vs. 29%, respectively; P =.034). An aberrant nuclear CRBP-1 accumulation resulting from cytoplasmic invagination was found in 29% of HCCs. Nuclear CRBP-1 staining correlated positively with a favorable tumor stage (Okuda stage I; P =.01) and negatively with the Ki-67(+) proliferation fraction (PF). A Ki-67(+) PF of > or =10% was associated with a lower 2-year survival probability as compared with patients with a Ki-67(+) PF of <10% (12% vs. 40%, respectively; P =.015). Prognosis did not correlate with the nuclear beta-catenin expression. There was, however, a close correlation between nuclear CRBP-1 inclusions and nuclear beta-catenin staining in HCCs (P =.008), suggesting a cross talk between CRBP-1 and the Wnt/wingless signal transduction pathway. In conclusion, our findings demonstrate that CRBP-1 detection may be useful for the discrimination between nonneoplastic and neoplastic liver cells and suggest that modulation of CRBP-1 expression in HCCs contributes to tumor growth and progression via retinoid-mediated signaling and disruption of cellular vitamin A homeostasis.

EBAG9/RCAS1 expression in hepatocellular carcinoma: correlation with tumour dedifferentiation and proliferation

The oestrogen-responsive gene, EBAG9, whose product is identical to the cancer cell surface antigen RCAS1, is reported to be associated with tumour progression and invasiveness in various carcinomas. In this study, we examined the expression of EBAG9/RCAS1 in hepatocellular carcinoma (HCC), with special reference to its relationship with the stepwise evolution of HCC. Expression was examined by immunohistochemistry and western blotting analysis in 143 HCCs, as well as in non-cancerous liver tissues. After which, the association between enhanced EBAG9/RCAS1 expression and various clinicopathological parameters including Ki-67 labelling index (LI), a marker of proliferative activity, was evaluated. There was a constant low level of EBAG9/RCAS1 expression in non-cancerous liver tissues, with a regular cytoplasmic distribution. Positive immunoreactivity for EBAG9/RCAS1 was detected on the surface and in the cytoplasm of 84 HCC tumours, with an irregular staining pattern. Enhanced EBAG9/RCAS1 expression was correlated with a lower degree of differentiation and Ki-67 LI. Interestingly, expression was enhanced specifically in the less differentiated lesions within 'nodule-in-nodule' tumours. In conclusion, EBAG9/RCAS1 was associated with HCC tumour dedifferentiation and increased proliferative activity. Its exact functional role remains to be established.

Hepatocellular carcinoma and markers of apoptosis (bcl-2, bax, bcl-x): prognostic significance

Patients with tumors expressing promoters of apoptosis (bax) versus inhibitors of apoptosis (bcl-2, bcl-x) may have increased survival. The purpose of this study was to determine the frequency of expression of apoptotic markers in hepatocellular carcinoma (HCC) and their relationship with prognosis. Seventy HCC were immunostained for bcl-2, bax, and bcl-x. Staining intensity in tumor cells was graded 0 to 3+. Follow-up data were available for mean survival (57 cases) and death rates (58 cases). These values and clinical parameters were related to prognosis. Staining frequency for bcl-2, bax, and bcl-x was 20%, 66%, and 60%, respectively. Immunostaining intensity of bax correlated with overall survival and death rates: of 57 patients, the 37% with 0 to 1+ intensity had a median survival of 6.6 months, the 63% with 2 to 3+ intensity had a median survival of 31.9 months (P = 0.05); 86% of 19 patients with 0 to 1+ intensity died, and 50% of 36 patients with 2 to 3+ intensity died (P < 0.05). Intensity of bcl-x staining tended to correlate with survival: of the 57 patients with 0 to 1+, 42% had a median survival of 32.7 months compared with 5.8 months in the 58% with 2 to 3+ intensity (P = 0.06). By multivariate analysis, this relationship held for bax (P = 0.011) and bcl-x (P = 0.048). There was no correlation between bcl-2 expression, stage, or gender and prognosis. Patients with bax-expressing HCC experience improved survival compared with those with no or low bax expression, in uni- and multivariate models. Patients with no or low bcl-x tended toward improved survival compared with patients with more bcl-x in their HCC. bcl-2 expression did not correlate with prognosis.

p27(Kip1) is an independent predictor of recurrence after surgical resection in patients with small hepatocellular carcinoma

BACKGROUND/AIMS

Alterations in p27(Kip1) (p27) and cyclin E (cycE) expression are found in tumors and are related to poor prognosis. This study assesses the role of these cell cycle regulators in the development of recurrence after surgical resection in 46 cirrhotic patients (age: 61.3+/-7 years, 30 males, 44 Child-Pugh's A, 30 HCV-positive) with small hepatocellular carcinoma (HCC, size: 3.1+/-1.5cm, 40 solitary at pathological examination).

METHODS

p27 and cycE expression in tumoral and non-tumoral liver were analyzed by Western blot (WB). p27 was also assessed by immunohistochemistry (IHC).

RESULTS

Tumor p27 underexpression (50% decreased vs. non-tumoral liver) occurred in 12 cases. Throughout follow-up, 26 patients developed recurrence, which was significantly higher in patients with p27 underexpression than in those without (3-year recurrence: 80 vs. 44%, respectively, P=0.026). IHC showed concordant inverse findings: 13 tumors showed high p27 staining that was related to lower recurrence rate (P=0.019). Multivariate analysis identified p27 measured by WB as an improved predictor of recurrence (OR: 3.09, 95% CI: 1.26-7.08, P=0.016). By contrast, cycE, increased in 66% of the tumors, had no impact on recurrence but was associated to poor differentiation (P=0.015) and microvascular invasion (P=0.016).

CONCLUSIONS

p27 underexpression is frequent in relatively early stages of HCC and constitutes an independent predictor of recurrence after surgical resection.

Expression of survivin protein in hepatocellular carcinoma tissues and its relationship with clinical pathological features and prognosis

AIM

To investigate the expression of survivin protein in human hepatocellular carcinoma (HCC) and its relationship with clinical features and prognosis of patients with HCC.

METHODS

The expression of survivin protein and the proliferation of tumor cells marked by PCNA in 48 cases of HCC were assessed by immunohistochemical method. TUNEL method was used to detect apoptosis.

RESULTS

The survivin protein was expressed in 31 of 48 cases of HCC (64.6%). Expression of survivin protein was significantly higher in those of Edmondson grade Ⅲ-Ⅳ than in those of grade Ⅰ-Ⅱ (88.0% vs 39.1%, P = 0.013). The ratio of proliferative index to apoptotic index was significantly higher in HCC with positive survivin expression than that with negative survivin expression (1.8 vs 1.1, P = 0.045). The survival rate of three years of patients with positive survivin expression was significantly lower than that of patients with negative survivin expression (70.6% vs 35.5%, P = 0.011).

CONCLUSION

The expression of survivin may play an important role in breaking the balance of proliferation and apoptosis of HCC cells and is closely associated with prognosis of patients with HCC.

Hepatocyte growth factor, transforming growth factor alpha, and their receptors as combined markers of prognosis in hepatocellular carcinoma

A change in the balance between proliferation and apoptosis in the course of hepatocellular carcinoma (HCC) development and progression has been suspected. We wanted to identify related genes whose mRNA levels could provide markers of severity and prognosis after resection. The extent of cell apoptosis, proliferation, and differentiation was measured with a terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate-biotin nick-end labeling assay, and the Ki-67 index was determined in paired tumor and cirrhotic tissue samples from patients who had undergone HCC resection after diagnosis of hepatitis C-related or alcoholism-related cirrhosis. These patients included two groups with highly versus poorly differentiated tumor cells, and the latter was split into two subgroups of those with versus without early recurrence. The mRNA levels for various apoptosis-related or proliferation-related genes and those for the growth factor/receptor systems were measured by quantitative reverse transcriptase-polymerase chain reaction in paired tumor and cirrhotic liver samples from every patient, and some of the corresponding proteins were detected by immunohistochemistry. In all instances, protein expression was highly heterogeneous within groups and similar between groups. In contrast, some differences in mRNA level between tumor and cirrhotic tissues were quite informative. Low levels of hepatocyte growth factor and transforming growth factor alpha mRNAs were found concomitantly in highly differentiated tumors, whereas overexpression of mRNAs for the cognate receptors c-met and epidermal growth factor receptor were found in poorly differentiated tumors and primarily in patients with early tumor recurrence. These results argue for growth factor-dependent HCC development and provide novel and combined prognosis markers after HCC surgery.

Quantitative analysis of apoptosis-related gene expression in hepatocellular carcinoma

BACKGROUND

The suppression of apoptosis is an important factor in tumor progression in hepatocellular carcinoma (HCC). However, to the authors knowledge the clinicopathologic importance of the expression of apoptosis-related genes (bcl-2, bax, and survivin) in HCC remains unclear. In the current study, the authors investigated the correlation between expression of apoptosis-related genes and the occurrence of spontaneous apoptosis in HCC. In addition, the prognostic significance of the expression of apoptosis-related genes in patients with HCC was analyzed.

METHODS

Tissue samples were obtained through surgical resection of the liver in 53 patients with HCC and 5 patients without HCC. The expression levels of bcl-2, bax, survivin, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA were analyzed using real-time reverse transcriptase-polymerase chain reaction (RT-PCR). The bcl-2/bax ratio and survivin/GAPDH ratio of the tumors were compared with clinicopathologic findings. In addition, apoptotic tumor cells and the proliferative activity of tumor cells were detected using immunohistochemistry.

RESULTS

The bcl-2/bax ratios of the tumors were not different from those of noncancerous liver tissue samples obtained from regions distant from the tumors and were not found to correlate with apoptosis or with clinical importance in HCC. In contrast, the survivin/GAPDH ratios of the tumors were significantly higher than those of noncancerous liver tissue and demonstrated a negative correlation with apoptosis and a positive correlation with the proliferative activity of tumor cells. Moreover, patients who had tumors with a high survivin/GAPDH ratio were found to have a high incidence of disease recurrence.

CONCLUSIONS

The real-time RT-PCR method appears to be a useful technique with which to detect reliable gene expression in tissues, and the detection of survivin mRNA expression by this method may be a useful marker for identifying patients with HCC who have a high risk of disease recurrence.

Hepatocellular carcinoma with an unusual medullary-like histology and signs of regression ("medullary-like hepatocellular carcinoma")

The case of a variant of hepatocellular carcinoma is described, which, based on its unique histology, we propose to term, medullary-like hepatocellular carcinoma. It developed in a 56-year-old male patient with liver cirrhosis, and consisted of large, amphophilic cells with a solid growth pattern. The tumour was densely infiltrated with lymphocytes and plasma cells. Lymphocytes formed a mixture of B and T cells, and plasma cells were polytypic. In addition, numerous S-100 protein-reactive stellate cells were observed at the tumour border, where marked apoptosis of hepatocellular carcinoma cells was evident. In areas of dense lymphoplasmacytic infiltration, part of the tumour cells had lost their intercellular connections and their beta-catenin reactivity. Some tumour cells expressed FasL, but not Fas. The tumour exhibited several foci of regression, showing small remnants of damaged tumour cells within dense infiltrations. The patient is alive without evidence of disease 25 months after resection. Medullary-like hepatocellular carcinoma is a lesion which mimics several features known for other medullary carcinomas, including a marked immune response which may be responsible for partial regression of this tumour.

Hepatocellular carcinoma and markers of apoptosis (bcl-2, bax, bcl-x): prognostic significance

Patients with tumors expressing promoters of apoptosis (bax) versus inhibitors of apoptosis (bcl-2, bcl-x) may have increased survival. The purpose of this study was to determine the frequency of expression of apoptotic markers in hepatocellular carcinoma (HCC) and their relationship with prognosis. Seventy HCC were immunostained for bcl-2, bax, and bcl-x. Staining intensity in tumor cells was graded 0 to 3+. Follow-up data were available for mean survival (57 cases) and death rates (58 cases). These values and clinical parameters were related to prognosis. Staining frequency for bcl-2, bax, and bcl-x was 20%, 66%, and 60%, respectively. Immunostaining intensity of bax correlated with overall survival and death rates: of 57 patients, the 37% with 0 to 1+ intensity had a median survival of 6.6 months, the 63% with 2 to 3+ intensity had a median survival of 31.9 months (P = 0.05); 86% of 19 patients with 0 to 1+ intensity died, and 50% of 36 patients with 2 to 3+ intensity died (P < 0.05). Intensity of bcl-x staining tended to correlate with survival: of the 57 patients with 0 to 1+, 42% had a median survival of 32.7 months compared with 5.8 months in the 58% with 2 to 3+ intensity (P = 0.06). By multivariate analysis, this relationship held for bax (P = 0.011) and bcl-x (P = 0.048). There was no correlation between bcl-2 expression, stage, or gender and prognosis. Patients with bax-expressing HCC experience improved survival compared with those with no or low bax expression, in uni- and multivariate models. Patients with no or low bcl-x tended toward improved survival compared with patients with more bcl-x in their HCC. bcl-2 expression did not correlate with prognosis.

The prognostic molecular markers in hepatocellular carcinoma

The prognosis of hepatocellular carcinoma (HCC) still remains dismal, although many advances in its clinical study have been made. It is important for tumor control to identify the factors that predispose patients to death. With new discoveries in cancer biology, the pathological and biological prognostic factors of HCC have been studied quite extensively. Analyzing molecular markers (biomarkers) with prognostic significance is a complementary method. A large number of molecular factors have been shown to associate with the invasiveness of HCC, and have potential prognostic significance. One important aspect is the analysis of molecular markers for the cellular malignancy phenotype. These include alterations in DNA ploidy, cellular proliferation markers (PCNA, Ki-67, Mcm2, MIB1, MIA, and CSE1L/CAS protein), nuclear morphology, the p53 gene and its related molecule MD M2, other cell cycle regulators (cyclin A, cyclin D, cyclin E, cdc2, p27, p73), oncogenes and their receptors (such as ras, c-myc, c-fms, HGF, c-met, and erb-B receptor family members), apoptosis related factors (Fas and FasL), as well as telomerase activity. Another important aspect is the analysis of molecular markers involved in the process of cancer invasion and metastasis. Adhesion molecules (E-cadherin, catenins, serum intercellular adhesion molecule-1, CD44 variants), proteinases involved in the degradation of extracellular matrix (MMP-2, MMP-9, uPA, uPAR, PAI), as well as other molecules have been regarded as biomarkers for the malignant phenotype of HCC, and are related to prognosis and therapeutic outcomes. Tumor angiogenesis is critical to both the growth and metastasis of cancers including HCC, and has drawn much attention in recent years. Many angiogenesis-related markers, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived endothelial cell growth factor (PD-ECGF), thrombospondin (TSP), angiogenin, pleiotrophin, and endostatin (ES) levels, as well as intratumor microvessel density (MVD) have been evaluated and found to be of prognostic significance. Body fluid (particularly blood and urinary) testing for biomarkers is easily accessible and useful in clinical patients. The prognostic significance of circulating DNA in plasma or serum, and its genetic alterations in HCC are other important trends. More attention should be paid to these two areas in future. As the progress of the human genome project advances, so does a clearer understanding of tumor biology, and more and more new prognostic markers with high sensitivity and specificity will be found and used in clinical assays. However, the combination of some items, i.e., the pathological features and some biomarkers mentioned above, seems to be more practical for now.

Expression of p57/Kip2 protein in hepatocellular carcinoma

Evaluation of the biological character of carcinomas requires understanding of cell cycle regulators. In the present study, we investigated the expression of p57 (Kip2) in 90 hepatocellular carcinomas and 66 noncancerous lesions. The average p57 labeling index in noncancerous lesions was 72.3 +/- 19.7. The labeling index significantly decreased (p < 0.0001) in hepatocellular carcinoma (54.9 +/- 19.7). It was significantly lower in hepatocellular carcinoma cases with high biological aggressiveness such as advanced stage (p = 0.0041), poor differentiation (p < 0.0001), larger size (p = 0.0400), portal invasion (p < 0.0001), satellite tumor (p = 0.0023), high proliferating activity (p = 0.0002) and cyclin D(1) overexpression (p = 0.0416). Furthermore, cases with low p57 expression showed worse outcomes for disease-free survival in univariate analysis (p = 0.0235), although p57 expression could not be recognized as an independent prognostic factor. These findings suggest that p57 contributes to the downregulation of cell proliferation and to the progression of hepatocellular carcinoma.

Hepatocellular carcinomas in native livers from patients treated with orthotopic liver transplantation: biologic and therapeutic implications

The gross and histopathologic characteristics of 212 nonfibrolamellar hepatocellular carcinomas (HCCs) discovered in native livers removed at the time of liver transplantation were correlated with features of invasive growth and tumor-free survival. The results show that most HCCs begin as small well-differentiated tumors that have an increased proliferation rate and induce neovascularization, compared with the surrounding liver. But at this stage, they maintain a near-normal apoptosis/mitosis ratio and uncommonly show vascular invasion. As tumors enlarge, foci of dedifferentiation appear within the neoplastic nodules, which have a higher proliferation rate and show more pleomorphism than surrounding better-differentiated areas. Vascular invasion, which is the strongest predictor of disease recurrence, correlates significantly with tumor number and size, tumor giant cells and necrosis, the predominant and worst degree of differentiation, and the apoptosis/mitosis ratio. In the absence of macroscopic or large vessel invasion, largest tumor size (P <.006), apoptosis/mitosis ratio (P <.03), and number of tumors (P <.04) were independent predictors of tumor-free survival and none of 24 patients with tumors having an apoptosis/mitosis ratio greater than 7.2 had recurrence. A minority of HCCs (<15%) quickly develop aggressive features (moderate or poor differentiation, low apoptosis/mitosis ratio, and vascular invasion) while still small, similar to flat carcinomas of the bladder and colon. In conclusion, hepatic carcinogenesis in humans is a multistep and multifocal process. As in experimental animal studies, aggressive biologic behavior (vascular invasion and recurrence) correlates significantly with profound alterations in the apoptosis/mitosis ratio and with architectural and cytologic alterations that suggest a progressive accumulation of multiple genetic abnormalities.

Expression and clinical significance of erb-B receptor family in hepatocellular carcinoma

In order to elucidate the clinical significance of the erbB family, epidermal growth factor receptor (EGF-R), c-erbB-2, c-erbB-3 and c-erbB-4 in hepatocellular carcinoma (HCC), we investigated the expression of these proteins by means of immunohistochemistry for HCC as well as adjacent noncancerous lesions. EGF-R was expressed in 68% of the HCC examined and showed correlation with the proliferating activity, stage, intrahepatic metastasis and carcinoma differentiation. c-erbB-2 was expressed in only 21% of the cases and showed no relationships with the clinicopathological parameters. c-erbB-3 protein was observed in 84% of the HCC and 38.1% of the noncancerous lesions. Its expression in HCC was equal to or greater than noncancerous lesions in 90.5% of the cases, and was related to the stage, portal invasion, cell proliferating activity, tumour size, intrahepatic metastasis and carcinoma differentiation. c-erbB-4 protein was expressed in 61.0% of HCC and in as much as 86.1% of the noncancerous lesions. Unlike the expression of c-erbB-3, that of c-erbB-4 in HCC was less than that of the adjacent noncancerous lesions in 51.2% of the cases. No statistical significance could be established between this protein expression in HCC and clinicopathological features. EGF-R and c-erbB-3 affected disease-free survival, but were not recognized as independent prognostic factors by multivariate analysis. The present study suggests that, of the four receptors, EGF-R and c-erbB-3 play important roles in the progression of HCC. © 2001 Cancer Research Campaign www.bjcancer.com

Expression and clinical significance of the G1-S modulators in intrahepatic cholangiocellular carcinoma

OBJECTIVE

To elucidate the clinical roles of G1-S modulators in cholangiocellular carcinoma (CCC).

METHODS

We performed immunohistochemistry using antibodies against the retinoblastoma gene product (pRb), p16, p21, p27, p53 and cyclin D1 for 41 cases of CCC as well as normal bile ducts.

RESULTS

The p27 labeling index (LI) was significantly higher in cases without lymph node metastasis than in normal bile ducts, but it decreased greatly in cases with lymph node metastasis. It was inversely related to the Ki-67 LI. The p16 LI also showed a relationship with lymph node metastasis, but not with the Ki-67 LI. The p21 LI was even higher in poorly differentiated cases and showed a direct relationship with the Ki-67 LI, although it is a negative regulator of the cell cycle. pRb expression did not correlate with any clinicopathological features. Cyclin D1 overexpression was more frequently observed in cases with poor or moderate differentiation and with lymph node metastasis. Cyclin D1 overexpression and aberrant p53 expression showed direct relationships with the Ki-67 LI.

CONCLUSIONS

These results suggest that in CCC: (1) p27 expression reflects the biological character of the carcinoma and may regulate its progression; (2) cyclin D1 plays a crucial role in cell cycle progression, and (3) aberrant p53 expression has some effect on CCC cell proliferating activity.

Caspase-3 activity as a prognostic factor in colorectal carcinoma

Several techniques to determine apoptotic frequencies in tumors have been described. In this study, we report that biochemical detection of enzymatic caspase-3 activity is a simple and quantitative technique to measure apoptosis in colorectal tumor cells. The relevance of the level of apoptosis in colorectal cancer for the clinical course remains unclear. Therefore, we studied the correlation between caspase-3 activity and prognosis of the disease in relation to different factors known to be involved in apoptosis induction. High caspase-3 activity significantly correlated with a higher risk of recurrence and was preferentially found in tumors of the right side of the colon. No correlation was detected between high caspase-3 activity and altered protein expression of p53, beta-catenin, or proteins of mismatched repair genes. This indicates that high caspase-3 activity has no evident correlation with the genetic Wnt-signaling or the mismatch repair mutational pathways. The caspase-3 activity significantly correlated with CD57(+) tumor infiltrating cells. Therefore, high caspase-3 activity in right-sided tumors might be induced by a specific lymphocytic reaction.

Evaluation of cell proliferation, apoptosis, and angiogenesis in transitional cell carcinoma of the renal pelvis and ureter

OBJECTIVES

To investigate cell proliferation, apoptosis, and angiogenesis and their roles in transitional cell carcinoma (TCC) of the renal pelvis and ureter.

METHODS

Formalin-fixed and paraffin-embedded tissue blocks from 42 patients with TCC of the renal pelvis and ureter were studied. Cell proliferation was assessed by Ki-67 immunostaining, and the proliferation index (PI) was expressed as a percentage of Ki-67-positive cells. Apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and the apoptotic index (AI) was expressed as a percentage of TUNEL positive cells. Angiogenesis was evaluated by CD31 immunostaining, and microvessel density (MVD) was expressed as the average of the microvessel count.

RESULTS

The PI ranged from 5.9% to 48.0% (median 20.03%), AI from 1.0% to 4.2% (median 2.26%), and MVD from 16.0 to 146.0 (median 56.88) in TCC of the renal pelvis and ureter. Statistical analysis revealed close associations of both PI and MVD with tumor stage and of AI with tumor grade. Our study demonstrated a strong relationship between PI and MVD, but did not show associations of AI with PI or MVD in TCC of the renal pelvis and ureter.

CONCLUSIONS

It is suggested that the high activity of tumor cell proliferation with rich neovascularization may be related to the high malignant potential of the cancer, and evaluation of cell proliferation combined with angiogenesis may be useful in predicting the progression of the renal pelvic and ureteral TCC.

Cell proliferation and apoptosis with BCL-2 expression in renal cell carcinoma

OBJECTIVES

To investigate cell proliferation, apoptosis, and bcl-2 immunoreactivity in renal cell carcinoma (RCC).

METHODS

Formalin-fixed and paraffin-embedded tissue blocks from 70 patients with RCC were studied. Cell proliferation activity was detected by Ki-67 immunostaining and the proliferation index (PI) was expressed as a percentage of the Ki-67-positive cells in the tumor cells. Apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and the apoptotic index (AI) was expressed as a percentage of the TUNEL-positive cells in the tumor cells. Immunoreactivity of bcl-2 was assessed immunohistochemically and coexpression of Ki-67 with bcl-2 was examined by double immunostaining.

RESULTS

The PI ranged from 5.0% to 44.0% (median 19.23%) and the AI from 0.9% to 3.4% (median 2.13%) in RCC. Statistical analysis revealed close associations between PI and tumor grade and stage, and a significant relationship between AI and the tumor grade of RCC. The expression of bcl-2 was detected in 24 (34.3%) of 70 RCCs. Coexpression of Ki-67 with bcl-2 was noted in 3 of the 24 RCCs with bcl-2 expression. The expression of bcl-2 was not related to PI, AI, or the clinicopathologic factors of RCC.

CONCLUSIONS

Our observations suggest that active cell proliferation may be accompanied by frequent apoptosis and that cell proliferation as reflected by Ki-67 staining may be the most important parameter of cell turnover in RCC.