Overexpression of Testes-Specific Protease 50 (TSP50) Predicts Poor Prognosis in Patients with Gastric Cancer

Testes-specific protease 50 heightens stem-like properties and improves mitochondrial function in colorectal cancer

AIMS

The progression of colorectal cancer (CRC) is driven by a small subset of cancer stem-like cells (CSCs), and mitochondrial function is essential for maintaining their stemness. TSP50, a novel identified oncogene, has been found to promote cell proliferation in multiple cancer types. In this study, we detected the regulatory role of TSP50 in regulating CSC-like properties and mitochondrial mass in CRC.

MATERIALS AND METHODS

First, TSP50 expression and clinical relevance were analyzed via clinical databases and immunohistochemical (IHC). Subsequently, bioinformatic analyses, CRC cell lines, tumorsphere cultures, and mouse xenograft models were utilized to evaluate the relationship between TSP50 and CSC-like properties as well as mitochondrial mass. Finally, immunofluorescence, immunoprecipitation, and Western blotting were performed to dissect the regulatory mechanisms of TSP50, followed by rescue experiments conducted both in vitro and in vivo.

KEY FINDINGS

TSP50 was overexpressed in CRC tissues, correlating with poor drug response and shorter overall survival (OS). Meanwhile, TSP50 was shown to enhance CSC-like properties in both CRC cells and mouse xenograft models, while concurrently increasing mitochondrial mass and reducing ROS levels, these effects were partially reversed by inhibition of the PI3K/AKT pathway. Mechanistic investigations revealed that TSP50-induced activation of PI3K/AKT signaling is primarily mediated by the enhanced catalytic activity of PI3K p110α subunit.

SIGNIFICANCE

Collectively, TSP50 drives CRC malignancy by promoting CSC-like properties and enhancing mitochondrial function through PI3K/AKT signaling. These findings identify TSP50 as a potential therapeutic target for eliminating CSC-like cells and improving clinical outcomes in CRC treatment.

PRSS50-mediated inhibition of MKP3/ERK signaling is crucial for meiotic progression and sperm quality

Serine protease 50 (PRSS50/TSP50) is highly expressed in spermatocytes. Our study investigated its role in testicular development and spermatogenesis. Initially, PRSS50 knockdown was observed to impair DNA synthesis in spermatocytes. To further explore this, we generated PRSS50 knockout ( Prss50 -/- ) mice ( Mus musculus), which exhibited abnormal spermatid nuclear compression and reduced male fertility. Furthermore, dysplastic seminiferous tubules and decreased sex hormones were observed in 4-week-old Prss50 -/- mice, accompanied by meiotic progression defects and increased apoptosis of spermatogenic cells. Mechanistic analysis indicated that PRSS50 deletion resulted in increased phosphorylation of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) and elevated levels of MAP kinase phosphatase 3 (MKP3), a specific ERK antagonist, potentially accounting for testicular dysplasia in adolescent Prss50 -/- mice. Taken together, these findings suggest that PRSS50 plays an important role in testicular development and spermatogenesis, with the MKP3/ERK signaling pathway playing a significant role in this process.

Cancer/testis antigens: promising immunotherapy targets for digestive tract cancers

Digestive tract cancers, including esophageal, gastric, and colorectal cancers, are the major cause of death among cancer patients worldwide due to the heterogeneity of cancer cells, which limits the effectiveness of traditional treatment methods. Immunotherapy represents a promising treatment strategy for improving the prognosis of patients with digestive tract cancers. However, the clinical application of this approach is limited by the absence of optimal targets. Cancer/testis antigens are characterized by low or absent expression in normal tissues, but high expression in tumor tissues, making them an attractive target for antitumor immunotherapy. Recent preclinical trials have shown promising results for cancer/testis antigen-targeted immunotherapy in digestive cancer. However, practical problems and difficulties in clinical application remain. This review presents a comprehensive analysis of cancer/testis antigens in digestive tract cancers, covering their expression, function, and potential as an immunotherapy target. Additionally, the current state of cancer/testis antigens in digestive tract cancer immunotherapy is discussed, and we predict that these antigens hold great promise as an avenue for breakthroughs in the treatment of digestive tract cancers.

Expression of TSP50, SERCA2 and IL-8 in Colorectal Adenoma and Carcinoma: Correlation to Clinicopathological Factors

Background: Colorectal cancer (CRC) is the third most common type of cancer, it is considered a genetically heterogeneous disease with different molecular pathways being involved in its initiation and progression. Testes-specific protease 50 (TSP50) gene is a member of cancer/testis antigens that encodes for threonine protease enzyme. Overexpression of TSP50 was found to enhance the progression and invasion of breast cancer and other malignant tumors. SERCA2 is widely expressed in several body tissues; its aberrant expression has been involved in many cancers. IL-8 is an inflammatory cytokine. Alongside its role in inflammation, its expression was reported to induce the migration of tumor cells. Aim: Study the expression of TSP50, SERCA2 and IL-8 in colorectal adenoma (CRA), CRC and normal colonic tissues to compare the expression of these biomarkers in relation to clinicopathological parameters and prognostic factors. Results: TSP50, SERCA2 and IL-8 expression varied between normal colonic tissues, CRA and CRC. Significant statistical association was detected between the three biomarkers' overexpression and degree of dysplasia in CRA. Also, significant statistical relation was found between the three biomarkers' overexpression and presence of lympho-vascular invasion, advanced TNM staging and high intra-tumoral inflammatory infiltrate. Multivariable analysis showed that the overexpression of the three biomarkers is significantly associated with worse prognosis. Conclusion: The expression of TSP50, SERCA2 and IL-8 was different between the normal tissue and neoplastic colorectal tissue on one hand and between CRA and CRC on the other. Increased expression of these biomarkers in neoplastic epithelial cells of colorectal carcinoma is associated with adverse prognostic factors and could be considered as independent prognostic factors.

TSP50 promotes the Warburg effect and hepatocyte proliferation via regulating PKM2 acetylation

Metabolic reprogramming is a hallmark of malignancy. Testes-specific protease 50 (TSP50), a newly identified oncogene, has been shown to play an important role in tumorigenesis. However, its role in tumor cell metabolism remains unclear. To investigate this issue, LC-MS/MS was employed to identify TSP50-binding proteins and pyruvate kinase M2 isoform (PKM2), a known key enzyme of aerobic glycolysis, was identified as a novel binding partner of TSP50. Further studies suggested that TSP50 promoted aerobic glycolysis in HCC cells by maintaining low pyruvate kinase activity of the PKM2. Mechanistically, TSP50 promoted the Warburg effect by increasing PKM2 K433 acetylation level and PKM2 acetylation site (K433R) mutation remarkably abrogated the TSP50-induced aerobic glycolysis, cell proliferation in vitro and tumor formation in vivo. Our findings indicate that TSP50-mediated low PKM2 pyruvate kinase activity is an important determinant for Warburg effect in HCC cells and provide a mechanistic link between TSP50 and tumor metabolism.

PRSS50 is a testis protease responsible for proper sperm tail formation and function

Multiple morphological abnormalities of the sperm flagella (MMAF) are a major cause of asthenoteratozoospermia. We have identified protease serine 50 (PRSS50) as having a crucial role in sperm development, because Prss50-null mice presented with impaired fertility and sperm tail abnormalities. PRSS50 could also be involved in centrosome function because these mice showed a threefold increase in acephalic sperm (head-tail junction defect), sperm with multiple heads (spermatid division defect) and sperm with multiple tails, including novel two conjoined sperm (complete or partial parts of several flagellum on the same plasma membrane). Our data support that, in the testis, as in tumorigenesis, PRSS50 activates NFκB target genes, such as the centromere protein leucine-rich repeats and WD repeat domain-containing protein 1 (LRWD1), which is required for heterochromatin maintenance. Prss50-null testes have increased IκκB, and reduced LRWD1 and histone expression. Low levels of de-repressed histone markers, such as H3K9me3, in the Prss50-null mouse testis may cause increases in post-meiosis proteins, such as AKAP4, affecting sperm formation. We provide important insights into the complex mechanisms of sperm development, the importance of testis proteases in fertility and a novel mechanism for MMAF.

Expression and effects of TSP50 in mouse embryo and cardiac myocyte development

TSP50, a testis-specific gene encoding a serine protease-like protein, was specifically expressed in the spermatocytes of testes but abnormally activated and expressed in many different kinds of cancers. Here, we aimed to analyze the expression of TSP50 in mouse embryo and its function in early embryonic development. Firstly, the distribution of TSP50 in oocytes and embryonic development was characterized by immunofluorescence, RT-PCR and western blotting, and the results showed that TSP50 was detected at all studied stages with a dynamic expression pattern. When overexpressed TSP50 in zygotes by microinjection, the zygotes development was highly accelerated. On the contrary, knocking down TSP50 expression by RNA interference greatly retarded the zygote development. Furthermore, TSP50 expression at embryonic day 6.5 (E6.5), day 8.5 (E8.5) and day 10.5 (E10.5) were increasingly enhanced, However, the expression of TSP50 decreased gradually in the development and differentiation of cardiac myocyte from E12.5 to postnatal (P0). Additionally, we found that TSP50 expression was decreased during cardiac myocyte differentiation of P19 cells. Overexpression of TSP50 could decrease the expression of GATA-4, and knockdown of TSP50 markedly increase the expression of GATA-4. Taken together, our data indicate that TSP50 may play an important role during the process of mouse embryonic development as well as myocardial cell differentiation.

Testes-specific protease 50 as an independent risk factor for poor prognosis in patients with non-small cell lung cancer

Testes-specific protease 50 (TSP50) is normally expressed in the testes and is overexpressed in various types of human cancers, including breast cancer, colorectal carcinoma and laryngocarcinoma. However, little has been reported on the association between TSP50 and non-small cell lung cancer (NSCLC). The present study aimed to detect TSP50 expression in 198 strict follow-up cases of paired NSCLC and 15 cases of normal lung parenchymal specimens using immunohistochemical staining. The expression levels of TSP50 were then correlated with the clinicopathological factors of NSCLC to assess its potential diagnostic and prognostic value. The relationship between TSP50 expression and the clinicopathological parameters of NSCLC was evaluated using χ² and Fisher's exact tests. Survival rates for the overall population (n=198) were calculated using the Kaplan-Meier method, and univariate and multivariate analyses were performed using the Cox's proportional hazards regression model. P<0.05 was considered to indicate a statistically significant difference. The expression of TSP50 was significantly increased in NSCLC tissue compared with in adjacent non-tumor or normal lung parenchymal tissue (P<0.001). A significant association was revealed between high expression levels of TSP50 and clinicopathological characteristics including tumor differentiation (P=0.012), late tumor status (P=0.004) and late tumor node metastasis stage (P=0.026), as well as a reduced disease free survival (P=0.009) and overall survival rate (P=0.002) in all patients with NSCLC. Multivariate analyses demonstrated that high TSP50 expression in tumor tissues was significantly associated with a shorter disease-free survival rate [hazard ratio (HR) =1.590, 95% confidence interval (CI): 1.035-2.441], and with a shorter overall survival rate (HR=1.814; 95% CI: 1.156-2.846). In conclusion, the present data demonstrated that increased TSP50 protein expression may be a potential predictor of early recurrence and poor prognosis in NSCLC, and that TSP50 expression levels possess the potential to be used as a biomarker and therapeutic target for the treatment of patients with NSCLC.

Testes-specific protease 50 (TSP50) promotes invasion and metastasis by inducing EMT in gastric cancer

Background

TSP50 (testes-specific protease 50) has been reported to be a candidate oncogene and is overexpressed in various cancers. Our previous study demonstrated that TSP50 protein is elevated in gastric cancer, and its high expression is associated with unfavorable prognosis and lymph node metastasis. However, the role of TSP50 in gastric cancer remains elusive.

Methods

qRT-PCR, western blot were used to determine TSP50 expression in gastric cancer cell lines. Role of TSP50 in proliferation and invasion was examined by BrdU incorporation assay, cell count, wound healing and transwell assay. Immunohistochemistry and western blot were performed to identify the potential mechanisms involved.

Results

TSP50 was highly expressed in most of the gastric cancer cell lines at both mRNA and protein levels. Up-regulation of TSP50 in gastric cancer cells enhanced proliferation and invasiveness, whereas down-regulation of TSP50 by its specific shRNA decreased it. A negative correlation between TSP50 and E-Cadherin was found in gastric cancer tissues, and combination of them improves the prediction for prognosis and lymph node metastasis. Mechanistic studies revealed that overexpression of TSP50 increased the expression of epithelial-to-mesenchymal transition (EMT) markers including Vimentin, and Twist, and decreased the epithelial marker E-Cadherin. NF-κB signaling pathway is involved in the regulatory effects of TSP50 on EMT, migration and invasion in gastric cancer cells.

Conclusion

TSP50 promotes the proliferation, migration and invasion of gastric cancer cells involving NF-κB dependent EMT activation. Targeting TSP50 may provide a novel therapeutic strategy for the management of gastric cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4000-y) contains supplementary material, which is available to authorized users.

Testes-specific protease 50 promotes cell proliferation via inhibiting activin signaling

Testes-specific protease 50 (TSP50), a novelly identified oncogene, has the capacity to induce cell proliferation, cell invasion and tumor growth. Further studies indicated that CAGA-luc (an activin-responsive reporter construct) reporter activity could be significantly suppressed by TSP50 overexpression, implying that the activin signaling may participate in TSP50-mediated cell proliferation. Here, we reported that TSP50 had an inhibitory effect on activin signaling. Mechanistic studies revealed that TSP50 could interact with ActRIIA, inhibit activin typeIreceptor (ActRIB) phosphorylation, repress Smad2/3 nuclear accumulation and finally promote cell proliferation by reducing the expression of activin signal target gene p27. Additionally, we found that ActRIB activation could reverse TSP50-mediated cell proliferation and tumor growth. Furthermore, analysis of human breast cancer specimens by immunohistochemistry indicated that TSP50 expression was negatively related to p-Smad2/3 and p27 protein levels. Most importantly, breast cancer diagnosis-related indicators such as tumor size, tumor grade, estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) levels, were correlated well with TSP50/p-Samd2/3 and TSP50/p27 expression status. Thus, our studies revealed a novel regulatory mechanism underlying TSP50-induced cell proliferation and provided a new favorable intervention target for the treatment of breast cancer.

TBL1XR1 Is Highly Expressed in Gastric Cancer and Predicts Poor Prognosis

Objective. To investigate the expression of transducin- (β-) like 1 X-linked receptor 1 (TBL1XR1) in human gastric cancer (GC) and its correlation with prognostic and biologic significance. Methods. TBL1XR1 mRNA expression was analyzed in gastric cancer using a microarray dataset (GSE2701) from the Gene Expression Omnibus (GEO). Immunohistochemistry (IHC) analysis of TBL1XR1 was performed on GC tissue microarray (TMA) to assess its prognostic and biological significance in 334 patients of GC. Results. Analysis of GSE2701 showed that the mRNA levels of TBL1XR1 were significantly elevated in primary gastric tumor and lymph node tissues than normal gastric tissues (P < 0.05). The same results of TBL1XR1 protein level were observed by IHC staining in 334 GC tissues. 204 of 334 (60.1%) primary gastric cancer tissues showed high expression of TBL1XR1 protein. TBL1XR1 overexpression was significantly correlated with lymph node metastasis (P = 0.000) and advanced TNM stage (P = 0.001). Moreover, high levels of TBL1XR1 predicted worse overall survival (P = 0.015). Multivariate Cox regression analysis indicated that high expression of TBL1XR1 was an independent prognostic factor for poor overall survival (HR, 0.525; 95% confidence interval, 0.367–0.752; P = 0.005). Conclusion. This present study demonstrates that TBL1XR1 is overexpressed in gastric cancer and may be a potential predictor and therapeutic target for GC patients.

Protumoral TSP50 Regulates Macrophage Activities and Polarization via Production of TNF-α and IL-1β, and Activation of the NF-κB Signaling Pathway

Testes-specific protease 50 (TSP50) is abnormally overexpressed in many kinds of cancers and promotes cell proliferation and migration. However, whether TSP50 can influence the tumor microenvironment, especially the function of immune cells in the microenvironment, remains largely unknown. We demonstrated that exposure to the conditioned medium from TSP50-overexpressing cells, or co-culture with TSP50-overexpressing cells, enhanced the cytokine production and phagocytic activities of macrophages, and induced M2b polarization. Further investigation showed that production of TNF-α and IL-1β was strongly induced by TSP50 in TSP50-overexpressing cells. TSP50-induced TNF-α and IL-1β were main factors that mediated the effects of TSP50-overexpressing cells on macrophages. The NF-κB pathway could be activated in macrophages upon the treatment of conditioned medium of TSP50-overexpressing cells and its activation is necessary for the observed effects on macrophages. Taken together, our results suggested that oncogenic TSP50 expressed in cells could activate surrounding macrophages and induce M2b polarization, partly through inducing TNF-α/ IL-1β secretion and subsequent NF-κB pathway activation. This implies a potential mechanism by which oncogene TSP50 regulates tumor microenvironment to support tumor development.

Clinicopathological significance of cytoplasmic transducer of ErbB2. 1 expression in gastric cancer

The aim of the present study was to investigate the expression of transducer of ErbB2. 1 (TOB1) in gastric carcinoma and to clarify the association between TOB1 expression and the clinical significance of this expression in patients with gastric carcinoma. Western blot analysis was performed to confirm the expression of TOB1 in gastric cancer. Immunohistochemistry (IHC) was performed on a tissue microarray containing 90 pairs of primary gastric cancer and adjacent normal tissue samples. TOB1 expression was evaluated separately with cytoplasmic and nuclear staining. Western blot analysis revealed significantly lower expression levels of TOB1 in gastric cancer tissues than those in adjacent normal tissues in 91.7% of cases. This was confirmed by IHC, which revealed decreased cytoplasmic TOB1 expression in cancer tissues compared with those of normal tissue samples in 84.4% of cases. The IHC data also revealed low cytoplasmic expression of TOB1 in 67.8% of human gastric cancer samples. Nuclear TOB1 expression exhibited no significant association with specific pathological features. However, a significant association was identified between cytoplasmic expression levels of TOB1 and clinicopathological characteristics, including the depth of invasion (P=0.017), differentiation grade (P=0.034) and tumor-node-metastasis stage (P<0.000). In conclusion, cytoplasmic TOB1 expression was suggested to be significant in angiogenesis and cell differentiation in gastric cancer tissues and may be used as a potential prognostic marker.