p27(Kip1)is overexpressed in very early stages of hepatocarcinogenesis

The clinicopathological and prognostic significance of P27kip in hepatocellular carcinoma patients: A systemic review and meta-analysis

OBJECTIVES

P27^kip is a cyclin-dependent kinase inhibitor that has gained importance as a biomarker in human malignant tumors. However, the potential role of P27^kip in hepatocellular carcinoma remains unclear. The aim of this meta-analysis was to explore whether P27^kip acts as prognostic and clinicopathological roles in hepatocellular carcinoma patients.

METHODS/MATERIALS

An electronic search based on three databases, PubMed, Embase, and Web of Science, was performed to select a sufficient number of studies. Pooled hazard ratio (HR) and odds ratio (OR) were used as estimates to investigate the association among P27^kip expression, prognosis and clinicopathological features.

RESULTS

In total, we identified 18 studies with 1774 hepatocellular carcinoma patients. The result derived from four studies revealed a significant positive association between lower P27^kip levels and shorter overall survival (HR = 0.550, 95% CI: 0.464-0.652, P < 0001) and disease-free survival (HR = 0.420, 95% CI: 0.308-0.571, P < 0.0001). Analyses of the clinicopathological features and P27^kip expression also showed that a positive rate of P27^kip was significantly lower in a larger sized tumor (OR = 0.538, 95% CI: 0.315-0.919, P = 0.023). The results also revealed that lower P27^kip levels were correlated with poorer differentiation (0.416, 95% CI: 0.178-0.971, P = 0.043). Additionally, the pooled OR of 0.389 also presented a significant correlation between P27^kip underexpression and the metastasis of HCCs (95% CI: 0.155-0.975, P = 0.044).

CONCLUSIONS

This analysis suggests a strong association among P27^kip underexpression, poorer prognosis and aggressive progression of hepatocellular carcinoma in patients. P27^kip may be a tumor suppressor for predicting the progression and survival outcome in patients with hepatocellular carcinomas.

Heat shock protein 70 downregulation inhibits proliferation, migration and tumorigenicity in hepatocellular carcinoma cells

The overexpression of heat shock protein 70 (HSP70), a major stress-inducible heat shock protein, has been identified to enhance the proliferation, survival, invasion and metastasis of diverse types of human cancer. However, its role in hepatocellular carcinoma (HCC) remains poorly understood. The present study demonstrated that HSP70 expression was higher in tested HCC cell lines, compared with the normal hepatocyte LO2, and the suppression of HSP70 significantly inhibited the proliferation of SMMC-7721 and Hep3B cells. The growth inhibitory effect was mediated by cell cycle arrest at the G₁/S phase with reduced cyclin D1 and increased p27Kip1 expression. Furthermore, HSP70 knockdown significantly inhibited the migration and invasion abilities of HCC cells. In conclusion, HSP70 is a key regulator involved in the proliferation, migration and invasion of HCC, and it may be used as a potential therapeutic target for HCC.

Clinicopathology of recurrent hepatocellular carcinomas after radiofrequency ablation treated with salvage surgery

AIM

Radiofrequency ablation (RFA) is an effective standard local therapy for small hepatocellular carcinoma (HCC). However, local recurrence and/or tumor seeding after RFA remain major problems. For better understanding of underlying factors, we clarified clinicopathological features of recurrent HCC treated with RFA.

METHODS

This retrospective study included 21 patients who underwent surgical resection for HCC disease recurrence after RFA. Clinicopathological findings, including patterns of recurrence, immunohistochemical expression of proliferation markers (Ki-67 and p27(Kip1) ) and survival outcome were assessed.

RESULTS

The median time interval after RFA until the diagnosis of intrahepatic and/or extrahepatic tumor progression was 12 months (range, 3-84). Radical surgical resection was attempted for intrahepatic local recurrence in 16 patients (18 lesions), for peritoneal dissemination in four, for lymph node metastases in three and for adrenal metastasis in two. In 14 of the 21 (67%) patients, the recurrent HCC were histologically diagnosed as of poorly differentiated type. Their average Ki-67 and p27(Kip1) labeling indices were significantly higher (P = 0.020) and lower (P < 0.001), respectively, compared with values for the 108 HCC surgically resected at the initial treatment. Portal involvement was significantly higher (P = 0.01) in recurrent tumors after RFA (72%) than in HCC surgically resected at the initial treatment (43%). The mortality rate of salvage surgery was 0%, with cumulative survival rates at 1 and 3 years of 58.9% and 35.7%, respectively.

CONCLUSION

The recurrent tumors after RFA have characteristics of poor differentiation degree and abnormalities in cell-cycle regulators and are associated with aggressive vascular invasiveness.

p27 Is a critical prognostic biomarker in non-alcoholic steatohepatitis-related hepatocellular carcinoma

Non-alcoholic steatohepatitis (NASH) is a recently identified chronic liver disease, which progresses to liver cirrhosis and hepatocellular carcinoma (HCC). As the number of patients studied to date has been limited, clinically useful prognostic biomarkers of NASH-related HCC have not been available. In this study, we investigated the status of a cell-cycle regulator, p27, in NASH-related HCC. p27 has been regarded as a prognostic factor in various types of cancer patients. A total of 22 cases with NASH-related HCC were analyzed for p27 protein expression, and phosphorylation at threonine 157 (T157) and serine 10 (S10) by immunohistochemical analysis. The correlation of p27 with tumor characteristics, disease-free survival (DFS), and overall survival was analyzed. p27 expression was decreased in 13 HCCs (59%), and was significantly correlated with enlarged tumor size (p = 0.01) and increased cell proliferation (p < 0.01). Phospho-p27 at T157 and S10 was detected in four (18%) and seven (32%) cases, respectively, and patients positive for phospho-p27 (S10) showed reduced DFS (hazard ratio 7.623, p = 0.016) by univariate analysis. Further studies with more patients are required to verify the usefulness of p27 as a biomarker for predicting tumor recurrence in NASH patients.

Immunohistochemically detected expression of 3 major genes (CDKN2A/p16, TP53, and SMAD4/DPC4) strongly predicts survival in patients with resectable pancreatic cancer

OBJECTIVE

The goal of this retrospective study was to clarify the clinical implications of the status of the 3 major genes (CDKN2A/p16, TP53, and SMAD4/DPC4).

BACKGROUND

Recent whole-exome sequencing had shown that the landscape of the pancreatic ductal adenocarcinoma (PDAC) genome is notable for 4 frequently mutated genes (KRAS, TP53, CDKN2A/p16, and SMAD4/DPC4).

METHODS

We determined immunohistochemically the status of TP53, CDKN2A/p16, and SMAD4/DPC4 among the 4 genes because the KRAS gene is mutated in virtually all PDAC patients, and analyzed relationships with clinicopathological findings, including survival and patterns of disease progression, in 106 patients with PDAC undergoing radical surgery.

RESULTS

Abnormal immunolabeling of p53 was detected in 81.1% of PDACs and was significantly associated with tumor dedifferentiation (P = 0.022) and the presence of locoregional recurrence (P = 0.020). Loss of p16 and Smad4/Dpc4 immunolabeling was identified in 67.0% and 60.4%, respectively. Loss of p16 immunolabeling was associated with lymphatic invasion (P = 0.012) and postoperative widespread metastases (P < 0.001). A significant correlation was found between Smad4/Dpc4 immunolabeling and tumor size (P = 0.006), lymphatic invasion (P = 0.033), and lymph node metastasis (P = 0.006). Interestingly, all of the 6 patients demonstrating 5-year survival had intact SMAD4/DPC4. Kaplan-Meier survival analysis showed that lymph node metastasis (P = 0.001), lymphatic invasion (P = 0.008), the tumor (T) factor (T3 vs. T1/T2, P = 0.004), loss of p16 immunolabeling (P = 0.029), and loss of Smad4/Dpc4 immunolabeling (P < 0.001) were significantly associated with shorter overall survival. Multivariate analysis revealed that loss of Smad4/Dpc4 immunolabeling was an independent and significant poor prognostic factor for overall and disease-free survival. On analysis of combinations of the status of these 3 genes, increasing number of alterations reflected poorer survival.

CONCLUSIONS

Genetic alterations of these 3 genes and their accumulation are strongly associated with malignant behavior of PDAC. Their immunohistochemical assessment at the time of diagnosis may provide a new prognostic tool, assisting in deciding optimal therapeutic strategies for patients.

Altered expression of p27(Kip1) -interacting cell-cycle regulators in the adult testicular germ cell tumors: potential role in tumor development and histological progression

We examined the potential role of cell-cycle dysregulation in the development and histological progression of adult testicular germ cell tumors (TGCTs). Expressions of p27(Kip1) -interacting cell-cycle regulators (down-regulation of p27(Kip1) and overexpression of Skp2, Cks1, cyclin A, and cyclin E) and Ki-67 labeling index (LI) were immunohistochemically examined in histological components of 50 intratubular germ cell neoplasms, unclassified (IGCNUs); 74 seminomas; and 25 embryonal carcinomas, identified from 88 patients. Altered expression of p27(Kip1) , Skp2, Cks1, cyclin A, and cyclin E was observed in 20%, 12%, 16%, 10%, and 24% of IGCNUs; 26%, 36%, 27%, 89%, and 23% of seminomas; and 48%, 68%, 56%, 100%, and 60% of embryonal carcinomas, respectively. A significant difference in the frequency of Skp2 and cyclin A overexpression was observed between IGCNUs and seminomas. Significantly more frequent alterations of Skp2, Cks1, and cyclin E and p27(Kip1) were detected in embryonal carcinomas than in seminomas. Alterations of all cell-cycle regulators were significantly more frequent in embryonal carcinomas than in IGCNUs. The mean Ki-67 LI significantly increased from IGCNU (21.2%) through seminoma (34.7%) to embryonal carcinoma (54.2%). These results suggest that alterations of the p27(Kip1) -interacting cell-cycle regulators are common in TGCTs and may be involved in their histological progression.

FBI-1 promotes cell proliferation and enhances resistance to chemotherapy of hepatocellular carcinoma in vitro and in vivo

BACKGROUND

The so-called factor that binds to inducer of short transcripts-1 (FBI-1) purportedly plays an important role in tumorigenesis; however, its role in hepatocellular carcinoma (HCC) remains unknown. The objective of this study was to investigate the expression level, clinical relevance, and biologic function of FBI-1 in HCC.

METHODS

Real-time quantitative reverse transcriptase-polymerase chain reaction analysis, Western blot analysis, and immunohistochemical staining were used to detect expression levels of FBI-1 and to analyze its relation to clinicopathologic parameters and to the prognosis of patients with HCC. In addition, the biologic functions of FBI-1 in regulating cell proliferation, migration, and reaction to chemotherapy were detected by using HepG2 cells and SMMC-7721 cells; subsequently, the molecular mechanism of FBI-1 also was investigated. Finally, a xenograft mouse model was used to validate the observations obtained from in vitro studies.

RESULTS

Expression levels of FBI-1 messenger RNA and protein were elevated significantly in HCC tissues compared with adjacent nontumorous liver tissues (ANLTs). Increased FBI-1 expression was correlated with multiple tumor nodes, Edmondson-Steiner grade, and a poor prognosis in patients with HCC (P < .05). In vitro studies revealed that FBI-1 was capable of promoting cell proliferation (but not cell migration) by regulating the cell cycle regulation proteins p53, p21, and p27. In addition, FBI-1 could inhibit cell death induced by 5-fluorouracil or doxorubicin through suppressing the activation of p53. Consistent with the in vitro data, FBI-1 was capable of promoting cell proliferation and enhancing chemotherapy resistance of HCC in vivo.

CONCLUSIONS

The current findings indicated that FBI-1 plays an important role in HCC carcinogenesis and chemotherapy tolerance, and FBI-1 may served as a novel prognostic marker and therapeutic target for HCC.

Characteristic gene expression profiles in the progression from liver cirrhosis to carcinoma induced by diethylnitrosamine in a rat model

Background

Liver cancr is a heterogeneous disease in terms of etiology, biologic and clinical behavior. Very little is known about how many genes concur at the molecular level of tumor development, progression and aggressiveness. To explore the key genes involved in the development of liver cancer, we established a rat model induced by diethylnitrosamine to investigate the gene expression profiles of liver tissues during the transition to cirrhosis and carcinoma.

Methods

A rat model of liver cancer induced by diethylnitrosamine was established. The cirrhotic tissue, the dysplasia nodules, the early cancerous nodules and the cancerous nodules from the rats with lung metastasis were chosen to compare with liver tissue of normal rats to investigate the differential expression genes between them. Affymetrix GeneChip Rat 230 2.0 arrays were used throughout. The real-time quantity PCR was used to verify the expression of some differential expression genes in tissues.

Results

The pathological changes that occurred in the livers of diethylnitrosamine-treated rats included non-specific injury, fibrosis and cirrhosis, dysplastic nodules, early cancerous nodules and metastasis. There are 349 upregulated and 345 downregulated genes sharing among the above chosen tissues when compared with liver tissue of normal rats. The deregulated genes play various roles in diverse processes such as metabolism, transport, cell proliferation, apoptosis, cell adhesion, angiogenesis and so on. Among which, 41 upregulated and 27 downregulated genes are associated with inflammatory response, immune response and oxidative stress. Twenty-four genes associated with glutathione metabolism majorly participating oxidative stress were deregulated in the development of liver cancer. There were 19 members belong to CYP450 family downregulated, except CYP2C40 upregulated.

Conclusion

In this study, we provide the global gene expression profiles during the development and progression of liver cancer in rats. The data obtained from the gene expression profiles will allow us to acquire insights into the molecular mechanisms of hepatocarcinogenesis and identify specific genes (or gene products) that can be used for early molecular diagnosis, risk analysis, prognosis prediction, and development of new therapies.

Reliability of real-time reverse-transcription PCR in clinical diagnostics: gold standard or substandard?

Molecular diagnostics is one of the major growth areas of modern medicine, with real-time PCR established as a qualitative and quantitative technology that is rapid, accurate and sensitive. The sequencing of the human genome, comprehensive genomic, mRNA and miRNA expression profiling of numerous cancer types, the ongoing identification of disease-associated polymorphisms and the expanding availability of genomic sequence information for human pathogens has opened the door to a wide range of translational applications for this technology. Consequently, novel real-time PCR assays have been developed for diagnosis and prognosis, treatment monitoring, transplant biology and pathogen detection, as well as more controversial uses such as lifestyle genotyping. However, this technology is still troubled by significant technical deficiencies. Hence its often-improper use as a clinical tool has important public health implications, most recently demonstrated through its association with the measles, mumps and rubella vaccine/autism controversy. This serves as a timely reminder of the indispensable requirement for careful experimental design, validation and analysis.

Immunohistochemically detected expression of p27(Kip1) and Skp2 predicts survival in patients with intrahepatic cholangiocarcinomas

In intrahepatic cholangiocarcinomas (ICCs), the prognostic significance of p27(Kip1), a cyclin-dependent kinase inhibitor, remains controversial, and there have been no studies of degradation pathway associated proteins, S-phase kinase-interacting protein (Skp2), and Jun activation domain-binding protein-1 (Jab1). In the present study of 74 patients with ICC-mass forming type (ICC-MF) undergoing radical surgery, we determined immunohistochemical expression of p27(Kip1), Skp2, and Jab1 and examined relationships with clinicopathologic findings and patient survival. On the basis of the average of labeling indices, we set cutoff values to define high and low expressors and divided the cases into two groups. A statistically significant correlation was found between low p27(Kip1) expression and lymph node metastasis (P = .009). Patient survival in the low p27(Kip1) expression group (n = 25) was also significantly worse than that in the high p27(Kip1) expression group (n = 49, P = .0007). A significant inverse correlation was found between p27(Kip1) and Skp2 expression (P = .016). High Skp2 expression (n = 36) was significantly associated with poor prognosis (P = .0046). High Jab1 expression was observed in 32 cases, but there was no statistically significant relationship with clinicopathologic findings or patient survival. The multivariate analysis revealed that low p27(Kip1) and high Skp2 expression are independent and significant factors of poor prognosis. The results suggest that low p27(Kip1) and high Skp2 expression are associated with aggressive tumor behavior, and these cell-cycle regulators are useful markers to predict outcome of patients with ICC-MF.