PTP4A3 (PRL-3) expression correlate with lymphatic metastases in gastric cancer. Folia Histochem Cytobiol. 2010;48:632-636. [PMID: 21478108 DOI: 10.2478/v10042-010-0070-7]

PTP4A3 Is a Prognostic Biomarker Correlated With Immune Infiltrates in Papillary Renal Cell Carcinoma

PTP4A3 plays an important role in the tumorigenesis and metastasis of multiple tumors, but its prognostic role in renal cancer is not well understood. We utilized the Oncomine and Tumor Immunoassay Resource databases to examine the differential expression of PTP4A3 in tumor tissues and normal tissues in breast, urinary tract, gastrointestinal tract and skin. Using the GEPIA and PrognoScan databases, the independent prognostic role of PTP4A3 was confirmed in clear cell renal cell cancer and papillary renal cell cancer. Expression of PTP4A3 were obviously higher in tumor tissue compare with normal tissues (P=0.028). We haven’t found the associations of PTP4A3 and clinicopathological features in our IHC cohort. Ectopic expression of PTP4A3 promotes proliferation, migration and invasion and increased the mRNA level of TGFB1 in RCC cell lines. Immunohistochemical staining indicated that the expression of PTP4A3 associates with CD3+ (P =0.037)/CD8+ (P =0.037) intratumor TILs, not with invasive margins in renal cancer. Comprehensive analysis of immune infiltration in the TIMER database correlated PTP4A3 expression with the infiltration of B cells, CD8+ T cells, CD4+ T cells and neutrophils in both clear cell renal cell carcinoma and papillary renal cell carcinoma. PTP4A3 expression was associated with the infiltration of dendritic cells in papillary renal cell carcinoma. We further confirmed that the infiltration of B cells and CD8+ T cells was associated with poor prognosis in papillary renal cell carcinoma patients, consistent with the prognostic role of PTP4A3 in papillary renal cell carcinoma. PTP4A3 expression correlated genes involved in B cells, monocytes, M1 macrophages, Th2 and Treg cells in papillary renal cell carcinoma. These results suggest PTP4A3 as a prognostic factor with a role in regulating immune cell infiltration in papillary renal cell carcinoma.

A comprehensive review on the role of protein tyrosine phosphatases in gastric cancer development and progression

The main post-translational reversible modulation of proteins is phosphorylation and dephosphorylation, catalyzed by protein kinases (PKs) and protein phosphatases (PPs) which is crucial for homeostasis. Imbalance in this crosstalk can be related to diseases, including cancer. Plenty of evidence indicates that protein tyrosine phosphatases (PTPs) can act as tumor suppressors and tumor promoters. In gastric cancer (GC), there is a lack of understanding of the molecular aspects behind the tumoral onset and progression. Here we describe several members of the PTP family related to gastric carcinogenesis. We discuss the associated molecular mechanisms which support the down or up modulation of different PTPs. We emphasize the Helicobacter pylori (H. pylori) virulence which is in part associated with the activation of PTP receptors. We also explore the involvement of intracellular redox state in response to H. pylori infection. In addition, some PTP members are under influence by genetic mutations, epigenetics mechanisms, and miRNA modulation. The understanding of multiple aspects of PTPs in GC may provide new targets and perspectives on drug development.

Long Noncoding RNA UCA1 Regulates PRL-3 Expression by Sponging MicroRNA-495 to Promote the Progression of Gastric Cancer

Gastric cancer (GC) is among the most frequently occurring malignancies worldwide. In recent years, long noncoding RNAs (lncRNAs) have been widely studied because of their ability to regulate the cellular processes involved with tumorigenesis. The present study aims to investigate the underlying molecular mechanism by which lncRNA urothelial carcinoma-associated 1 (UCA1) influences the progression of GC. Differentially expressed lncRNA UCA1 was initially identified by microarray-based analysis, after which a high expression of UCA1 was determined in GC tissues and cells. It is important to note that UCA1 could upregulate the expression of phosphatase of regenerating liver-3 (PRL-3) by sponging miR-495. The expression of UCA1 and miR-495 was altered in human GC cells to evaluate cell activity in vitro, as well as peritoneal metastasis and tumor formation ability in vivo. Results suggested that increased expression of UCA1 promoted cell proliferation, migration, and invasion, accompanied by suppressed cell apoptosis, as well as enhanced peritoneal metastasis and tumorigenesis of GC cells. Meanwhile, the upregulated expression of miR-495 could reverse the promotive effects exerted by UCA1. Taken conjointly, UCA1, as a competing endogenous RNA (ceRNA) of miR-495, could accelerate the development of GC by upregulating PRL-3, highlighting a potentially promising basis for the targeted intervention treatment of GC.

PRL-3 is a potential glioblastoma prognostic marker and promotes glioblastoma progression by enhancing MMP7 through the ERK and JNK pathways

Purpose: Glioblastoma is the most common and aggressive type of primary brain malignancy and is associated with a poor prognosis. Previously, we found that phosphatase of regenerating liver-3 (PRL-3) was significantly up-regulated in glioblastoma as determined by a microarray analysis. However, the function of PRL-3 in glioblastoma remains unknown. We aimed to investigate the clinical relationship between PRL-3 and glioblastoma, and uncover the mechanisms of PRL-3 in the process of glioblastoma.

Methods: PRL-3 expression was evaluated in 61 glioblastoma samples and 4 cell lines by RT-qPCR and immunohistochemistry. Kaplan-Meier analysis was performed to evaluate the prognostic value of PRL-3 for overall survival (OS) and progression-free survival (PFS) for glioblastoma patients. Proliferation was evaluated by Cell Counting Kit-8 (CCK-8) assay and EdU proliferation assay, migration and invasion by wound-closure/Transwell assays, and qRT-PCR/immunoblotting/IHC were used for both in vivo and in vitro investigations.

Result: A high PRL-3 expression level was closely correlated with unfavorable OS and PFS for glioblastoma patients, and was also significantly correlated with Ki-67 expression. Down-regulation of PRL-3 inhibited glioma cell proliferation, invasion and migration through ERK/JNK/matrix metalloproteinase 7 (MMP7) in vitro and in vivo.

Conclusions: PRL-3 expression enhances the invasion and proliferation of glioma cells, highlighting this phosphatase as a novel prognostic candidate and an attractive target for future therapy in glioblastoma.

Role of phosphatase of regenerating liver 3 in gastric carcinoma

Gastric carcinoma is one of the most common malignancies worldwide and remains the third leading cause of cancer death in both sexes worldwide. Phosphatase of regenerating liver 3 (PRL-3) is a tyrosine phosphatase that has been reported to be overexpressed in gastric tissues and play an important role in lymphatic metastasis and peritoneal metastasis of gastric carcinoma. It has also been reported that PRL-3 has a negative relationship with the prognosis of gastric carcinoma patients. More and more researchers have focused on the regulatory mechanism of PRL-3 in gastric carcinoma, aiming to elucidate the possible pathway and influencing factors. However, the exact mechanism of PRL-3 in promoting lymphatic metastasis, peritoneal metastasis and recurrence of gastric cancer is unknown. This paper will review the role of PRL-3 in gastric carcinoma with regard to its structure, function and possible mechanism in gastric carcinoma development.

Phosphatase of regenerating liver-3 (PRL-3) is associated with metastasis and poor prognosis in gastric carcinoma

BACKGROUND

PRL-3 is a member of phosphatases of regenerating liver family, characterized by phosphatase active domain and C-terminal prenylation motif. Overexpression of PRL-3 has been implicated in multiple cancers. Here we examined the clinical significance of PRL-3 in gastric cancer together with its metastatic biological functions utilizing different structural mutants.

METHODS

PRL-3 expression was analyzed immunohistochemically in 196 gastric cancer patients and 21 cases of liver metastasis. A series of wild type PRL-3 or its mutant plasmids were expressed in BGC823 cells to investigate the relationship between its catalytic activity, cellular localization and metastatic potential in vitro.

RESULTS

Positive staining of PRL-3 was observed in 19.4% (38/196) gastric cancer tissues compared with 76.2% (16/21) in liver metastasis. Statistical analysis revealed that PRL-3 expression correlated with lymph node metastasis and vascular invasion (P<0.05). Patients with high PRL-3 expression showed poorer 5-year overall survival (P=0.011). Wild type PRL-3 expressing cells resulted in enhanced migration and invasion ability, which were greatly crippled in form of PRL-3(C104S) or PRL-3(ΔCAAX) mutants accompanied with its alteration in subcellular localization.

CONCLUSIONS

Metastasis associated protein PRL-3 may serve as a potential prognostic biomarker in human gastric cancer. Both the phosphatase catalytic activity and cellular localization are critical for its function.

Poor prognosis of phosphatase of regenerating liver 3 expression in gastric cancer: a meta-analysis

Background

Overexpression of phosphatase of regenerating liver 3 (PRL-3) has been implicated in gastric cancer (GC) metastasis. Epidemiological studies have evaluated the relationship between PRL-3 expression and prognosis in GC. However, results still remains controversial. In this study, a meta-analysis was performed to evaluate the association of PRL-3 expression with overall survival (OS) and clinicopathological characteristics.

Methods

Literature databases were searched to identify eligible studies dated until April 2013. Summary hazard ratios (HRs) or odds ratios (ORs) with 95% confidence interval (95% CI) were calculated to estimate the association.

Results

A total of 1380 GC patients from six studies were included in the meta-analysis. Overall, the combined HR estimate for OS in a random-effect model was 1.89 (95% CI = 1.38–2.60; P<0.001). Results showed that PRL-3 overexpression was significantly associated with OS, indicating that it may be a biomarker for poor prognosis of GC. Both subgroup and sensitivity analyses further identified the prognostic role of PRL-3 expression in GC patients. Moreover, PRL-3 overexpression was significantly associated with tumor stage (OR = 2.25; 95% CI = 1.63–3.12; P<0.001), depth of invasion (OR = 2.03; 95% CI = 1.38–2.98; P<0.001), vascular invasion (OR = 2.52; 95% CI = 1.79–3.56; P<0.001), lymphatic invasion (OR = 3.74; 95% CI = 2.49–5.63; P<0.001), and lymph node metastasis (OR = 4.56; 95% CI = 2.37–8.76; P<0.001). However, when age, sex, tumor size, and tumor differentiation were considered, no obvious association was observed.

Conclusions

This meta-analysis reveals significant association of PRL-3 overexpression with OS and some clinicopathological features in GC. PRL-3 may be a predicative factor of poor prognosis and aggressive tumor behavior in GC patients.