SPAG9 expression is increased in human prostate cancer and promotes cell motility, invasion and angiogenesis in vitro

The JNK-associated leucine zipper protein exerts a protective effect on renal parenchymal injury by limiting the inflammatory secretome in tubular cells

JNK-associated leucine zipper protein (JLP) is a newly identified renal endogenous anti-fibrotic factor that is selectively enriched in renal tubular epithelial cells (TECs). The loss of JLP by TECs is a landmark event that heralds the progression of kidney fibrosis. JLP deficiency ensues a series of pathogenetic cellular processes that are conducive to fibrotic injury. Inflammatory injury is functionally relevant in fibrotic kidneys, and TECs play an essential role in fueling inflammation through aberrant secretions. It is speculated that the loss of JLP in TECs is associated with the relentless inflammation during the development of kidney fibrosis. This study examined the alteration of a panel of inflammatory signatures in TECs under kidney fibrotic circumstances using a Jlp gene-modified unilateral ureteral obstruction (UUO) mouse model or cultured HK-2 cells. It was found that a deficiency of JLP in TECs led to a significant increase in the secretion of inflammatory cytokines including interleukin-1β (IL-1β), tumor necrosis factor (TNF-α), and monocyte chemotactic protein-1 (MCP-1), overactivation of the nuclear factor (NF)-κB/c-Jun N-terminal kinase (JNK) pathway, as well as nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome-mediated pyroptosis in response to pro-fibrotic damage. Additionally, the absence of JLP resulted in enhanced macrophage migration and fibroblast activation as paracrine effects elicited by injured TECs. In conclusion, the loss of JLP in TECs catalyses inflammatory injuries in the development of kidney fibrosis.

Transcriptomics Demonstrates Significant Biological Effect of Growing Stem Cells on RGD-Cotton Scaffold

Stem cell therapy provides a viable alternative treatment for degenerated or damaged tissue. Stem cells have been used either alone or in conjunction with an artificial scaffold. The latter provides a structural advantage by enabling the cells to thrive in three-dimensional (3D) settings, closely resembling the natural in vivo environments. Previously, we disclosed the development of a 3D scaffold made from cotton, which was conjugated with arginyl-glycyl-aspartic acid (RGD), to facilitate the growth and proliferation of mesenchymal stem cells (MSCs). This scaffold allowed the MSCs to adhere and proliferate without compromising their viability or their stem cell markers. A comprehensive analysis investigation of the molecular changes occurring in MSCs adhering to the cotton fibers will contribute to the advancement of therapy. The objective of this study is to analyze the molecular processes occurring in the growth of MSCs on a cotton-RGD conjugated-based scaffold by examining their gene expression profiles. To achieve this, we conducted an experiment where MSCs were seeded with and without the scaffold for a duration of 48 h. Subsequently, cells were collected for RNA extraction, cDNA synthesis, and whole-transcriptomic analysis performed on both populations. Our analysis revealed several upregulated and downregulated differently expressed genes in the MSCs adhering to the scaffold compared with the control cells. Through gene ontology analysis, we were able to identify enriched biological processes, molecular functions, pathways, and protein-protein interactions in these differentially expressed genes. Our data suggest that the scaffold may have the potential to enhance osteogenesis in the MSCs. Furthermore, our results indicate that the scaffold does not induce oxidative stress, inflammation, or aging in the MSCs. These findings provide valuable insights for the application of MSCs in tissue engineering and regenerative medicine.

SPAG9 Expression Predicts Good Prognosis in Patients with Clear-Cell Renal Cell Carcinoma: A Bioinformatics Analysis with Experimental Validation

Clear-cell renal cell carcinoma (ccRCC) is the most common and aggressive type of renal-cell carcinoma (RCC). Sperm-associated antigen 9 (SPAG9) has been reported to promote the progression of a variety of tumors and is thus a potential prognostic marker. This study combined a bioinformatics analysis with an experimental validation, exploring the prognostic value of SPAG9 expression in ccRCC patients and the possible underlying mechanisms. The SPAG9 expression was associated with a poor prognosis in pan-cancer patients, but with a good prognosis and slow tumor progression in ccRCC patients. To explore the underlying mechanism, we investigated the roles of SPAG9 in ccRCC and bladder urothelial carcinoma (BLCA). The latter was chosen for comparison with ccRCC to represent the tumor types in which SPAG9 expression suggests a poor prognosis. The overexpression of SPAG9 increased the expression of autophagy-related genes in 786-O cells but not in HTB-9 cells, and SPAG9 expression was significantly correlated with a weaker inflammatory response in ccRCC but not in BLCA. Through an integrated bioinformatics analysis, we screened out seven key genes (AKT3, MAPK8, PIK3CA, PIK3R3, SOS1, SOS2, and STAT5B) in this study. The correlation between SPAG9 expression and ccRCC prognosis depends on the expression of key genes. Since most of the key genes were PI3K-AKT-pathway members, we used the PI3K agonist 740Y-P to stimulate the 786-O cells, to mimic the effect of key-gene overexpression. Compared with the Ov-SPAG9 786-O cells, the 740Y-P further increased the expression of autophagy-related genes by more than twofold. Moreover, we constructed a nomogram based on SPAG9/key genes and other clinical features, which was proven to have some predictive value. Our study found that SPAG9 expression predicted opposite clinical outcomes in pan-cancer and ccRCC patients, and we speculated that SPAG9 suppresses tumor progression by promoting autophagy and inhibiting inflammatory responses in ccRCC. We further found that some genes might cooperate with SPAG9 to promote autophagy, and that these were highly expressed in the tumor stroma and could be represented by key genes. The SPAG9-based nomogram can help to estimate the long-term prognosis of ccRCC patients, indicating that SPAG9 is a potential prognostic marker for ccRCC.

The Contributions of Cancer-Testis and Developmental Genes to the Pathogenesis of Keratinocyte Carcinomas

Simple Summary

In addition to mutations, ectopically-expressed genes are emerging as important contributors to cancer development. Efforts to characterize the expression patterns in cancers of gamete-restricted cancer-testis antigens and developmentally-restricted genes are underway, revealing these genes to be putative biomarkers and therapeutic targets for various malignancies. Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC) are two highly-prevalent non-melanoma skin cancers that result in considerable burden on patients and our health system. To optimize disease prognostication and treatment, it is necessary to further classify the molecular complexity of these malignancies. This review describes the expression patterns and functions of cancer-testis antigens and developmentally-restricted genes in BCC and cSCC tumors. A large number of cancer-testis antigens and developmental genes exhibit substantial expression levels in BCC and cSCC. These genes have been shown to contribute to several aspects of cancer biology, including tumorigenesis, differentiation, invasion and responses to anti-cancer therapy.

Abstract

Keratinocyte carcinomas are among the most prevalent malignancies worldwide. Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC) are the two cancers recognized as keratinocyte carcinomas. The standard of care for treating these cancers includes surgery and ablative therapies. However, in recent years, targeted therapies (e.g., cetuximab for cSCC and vismodegib/sonidegib for BCC) have been used to treat advanced disease as well as immunotherapy (e.g., cemiplimab). These treatments are expensive and have significant toxicities with objective response rates approaching ~50–65%. Hence, there is a need to dissect the molecular pathogenesis of these cancers to identify novel biomarkers and therapeutic targets to improve disease management. Several cancer-testis antigens (CTA) and developmental genes (including embryonic stem cell factors and fetal genes) are ectopically expressed in BCC and cSCC. When ectopically expressed in malignant tissues, functions of these genes may be recaptured to promote tumorigenesis. CTAs and developmental genes are emerging as important players in the pathogenesis of BCC and cSCC, positioning themselves as attractive candidate biomarkers and therapeutic targets requiring rigorous testing. Herein, we review the current research and offer perspectives on the contributions of CTAs and developmental genes to the pathogenesis of keratinocyte carcinomas.

Uncovering the anti-angiogenic effect of semisynthetic triterpenoid CDDO-Im on HUVECs by an integrated network pharmacology approach

AIM

To reveal the molecular mechanism of anti-angiogenic activity of semisynthetic triterpenoid CDDO-Im.

MATERIALS AND METHODS

Using re-analysis of cDNA microarray data of CDDO-Im-treated human vascular endothelial cells (HUVECs) (GSE71622), functional annotation of revealed differentially expressed genes (DEGs) and analysis of their co-expression, the key processes induced by CDDO-Im in HUVECs were identified. Venn diagram analysis was further performed to reveal the common DEGs, i.e. genes both susceptible to CDDO-Im and involved in the regulation of angiogenesis. A list of probable protein targets of CDDO-Im was prepared based on Connectivity Map/cheminformatics analysis and chemical proteomics data, among which the proteins that were most associated with the angiogenesis-related regulome were identified. Finally, identified targets were validated by molecular docking and text mining approaches.

KEY FINDINGS

The effect of CDDO-Im in HUVECs can be divided into two main phases: the short early phase (0.5-3 h) with an acute FOXD1/CEBPA/JUNB-regulated pro-angiogenic response induced by xenobiotic stress, and the second anti-angiogenic step (6-24 h) with massive suppression of various angiogenesis-related processes, accompanied by the activation of cytoprotective mechanisms. Our analysis showed that the anti-angiogenic activity of CDDO-Im is mediated by its inhibition of the expression of PLAT, ETS1, A2M, SPAG9, RASGRP3, FBXO32, GCNT1 and HDGFRP3 and its direct interactions with EGFR, mTOR, NOS2, HSP90AA1, MDM2, SYK, IRF3, ATR and KIF14.

SIGNIFICANCE

Our findings provide valuable insights into the understanding of the molecular mechanisms of the anti-angiogenic activity of cyano enone-bearing triterpenoids and revealed a range of novel promising therapeutic targets to control pathological neovascularization.

Xenograft-derived mRNA/miR and protein interaction networks of systemic dissemination in human prostate cancer

BACKGROUND

Distant metastasis formation is the major clinical problem in prostate cancer (PCa) and the underlying mechanisms remain poorly understood. Our aim was to identify novel molecules that functionally contribute to human PCa systemic dissemination based on unbiased approaches.

METHODS

We compared mRNA, microRNA (miR) and protein expression levels in established human PCa xenograft tumours with high (PC-3), moderate (VCaP) or weak (DU-145) spontaneous micrometastatic potential. By focussing on those mRNAs, miRs and proteins that were differentially regulated among the xenograft groups and known to interact with each other we constructed dissemination-related mRNA/miR and protein/miR networks. Next, we clinically and functionally validated our findings.

RESULTS

Besides known determinants of PCa progression and/or metastasis, our interaction networks include several novel candidates. We observed a clear role of epithelial-to-mesenchymal transition (EMT) pathways for PCa dissemination, which was additionally confirmed by an independent human PCa model (ARCAP-E/-M). Two converging nodes, CD46 (decreasing with metastatic potential) and DDX21 (increasing with metastatic potential), were used to test the clinical relevance of the networks. Intriguingly, both network nodes consistently added prognostic information for patients with PCa whereas CD46 loss predicted poor outcome independent of established parameters. Accordingly, depletion of CD46 in weakly metastatic PCa cells induced EMT-like properties in vitro and spontaneous micrometastasis formation in vivo.

CONCLUSIONS

The clinical and functional relevance of the dissemination-related interaction networks shown here could be successfully validated by proof-of-principle experiments. Therefore, we suggest a direct pro-metastatic, clinically relevant role for the multiple novel candidates included in this study; these should be further exploited by future studies.

A negative feedback loop between JNK-associated leucine zipper protein and TGF-β1 regulates kidney fibrosis

Renal fibrosis is controlled by profibrotic and antifibrotic forces. Exploring anti-fibrosis factors and mechanisms is an attractive strategy to prevent organ failure. Here we identified the JNK-associated leucine zipper protein (JLP) as a potential endogenous antifibrotic factor. JLP, predominantly expressed in renal tubular epithelial cells (TECs) in normal human or mouse kidneys, was downregulated in fibrotic kidneys. Jlp deficiency resulted in more severe renal fibrosis in unilateral ureteral obstruction (UUO) mice, while renal fibrosis resistance was observed in TECs-specific transgenic Jlp mice. JLP executes its protective role in renal fibrosis via negatively regulating TGF-β1 expression and autophagy, and the profibrotic effects of ECM production, epithelial-to-mesenchymal transition (EMT), apoptosis and cell cycle arrest in TECs. We further found that TGF-β1 and FGF-2 could negatively regulate the expression of JLP. Our study suggests that JLP plays a central role in renal fibrosis via its negative crosstalk with the profibrotic factor, TGF-β1.

Cancer testis antigen SPAG9 is a promising marker for the diagnosis and treatment of lung cancer

Cancer testis antigen sperm-associated antigen 9 (SPAG9) is highly expressed in many types of cancers. In the present study, to obtain a better understanding of the relevance of SPAG9 in cancer diagnosis and treatment, the expression of SPAG9 mRNA and protein in lung cancer specimens was evaluated by RT-PCR, western blotting and immunohistochemistry. ELISA was used to quantify the SPAG9 autoantibody in the peripheral blood of lung cancer patients. The results showed that the expression of SPAG9 mRNA and protein in the lung cancer tissues was significantly higher than that in the adjacent non-cancerous tissues (P<0.01). The level of the SPAG9 autoantibody in the serum of lung cancer patients was significantly higher than the level in the healthy controls (P<0.001), and the level of the SPAG9 autoantibody in the serum of untreated patients was significantly higher than that in treated patients (P=0.002). SPAG9 IgG antibody levels were significantly lower in treated adenocarcinoma and small cell lung cancer patients than these levels in the untreated patients (P=0.006, P=0.026, respectively), while no statistical difference was found between treated and untreated squamous cell carcinoma patients. Our results suggest that the SPAG9 antibody in serum is a promising marker for the diagnosis of lung cancer, and the level of the humoral immune response to this antigen appears to be related to the type of lung cancer.

SPAG9 is involved in hepatocarcinoma cell migration and invasion via modulation of ELK1 expression

Background

Sperm-associated antigen 9 (SPAG9) is upregulated in several malignancies and its overexpression is positively correlated with cancer cell malignancies. However, the specific biological roles of SPAG9 in hepatocellular carcinoma (HCC) are less understood.

Methods

We analyzed SPAG9 and ETS-like gene 1, tyrosine kinase (ELK1) expression in 50 paired HCC specimens and adjacent noncancerous liver specimens using immunohistochemistry. SPAG9 small interfering RNA (siRNA) was used to knockdown SPAG9 expression in HCCLM3 and HuH7 cell lines. We used plasmids to upregulate ELK1 expression and siRNA to downregulate ELK1 expression in HuH7 cells. Quantitative real-time polymerase chain reaction and Western blot were used to evaluate the expression of SPAG9 and ELK1 at the mRNA and protein level, respectively. Wound healing, matrigel migration, and invasion analyses were performed to determine the effect of SPAG9 and ELK1 on HCC metastasis.

Results

SPAG9 and ELK1 were overexpressed in HCC tissue specimens and their expressions were higher in HCCLM3 and HuH7 cells compared to the low-metastatic HepG2 cells. Overexpression of SPAG9 was positively associated with tumor-node-metastasis staging (P=0.032), metastasis parameters (P=0.018) of HCC patients, and ELK1 expression (r=0.422, P<0.001) in HCC tissue specimens. In addition, knockdown of SPAG9 in HCCLM3 and HuH7 cells using siRNA significantly suppressed cell migration and invasion. Furthermore, we observed inhibition of ELK1 expression and p38 signaling. However, ELK1 overexpression reversed the inhibitory effects of SPAG9 siRNA on HCC cell metastasis and ELK1 depletion inhibited HuH7 cell migration and invasion.

Conclusion

SPAG9 overexpression was positively correlated with HCC metastasis and SPAG9-induced migration and invasion were partially dependent on ELK1 expression in HCC cell lines. These results suggest that SPAG9 may be a potential anti-metastasis target effective in HCC therapy.

Direct targeting sperm-associated antigen 9 by miR-141 influences hepatocellular carcinoma cell growth and metastasis via JNK pathway

BACKGROUND

The aberrant expression of sperm-associated antigen 9 (SPAG9) is associated with numerous cancers, including hepatocellular carcinoma (HCC). The exploration of molecules and mechanisms regulating SPAG9 expression may provide new options for HCC therapy.

METHODS

MiRNA target prediction programs were used to explore SPAG9-targeted miRNAs. SPAG9 and miR-141 expression were detected in HCC tissues and cell lines by Western blot and real-time PCR. Dual-luciferase reporter assay was utilized to validate SPAG9 as a direct target gene of miR-141. Cell proliferation, invasion, and migration assays were used to determine whether miR-141-mediated regulation of SPAG9 could affect HCC progression.

RESULTS

An inverse correlation was observed between SPAG9 and miR-141 expression in HCC tissues and cell lines. Dual-luciferase reporter assay further showed that SPAG9 was a direct target gene of miR-141. The ectopic expression of miR-141 could markedly suppress SPAG9 expression in HCC cells. MiR-141 overexpression also resulted in significantly reduced cell proliferation, invasion, and migration, and imitation of the SPAG9 knockdown effects on HCC cells. Furthermore, SPAG9 restoration in miR-141-expressing cells sufficiently attenuated the tumor-suppressive effects of miR-141. Finally, JNK activity was found to be reduced by miR-141 overexpression the same way as by SPAG9 silencing. The overexpression of SPAG9 lacking its 3'-UTR significantly restored JNK activity and its downstream genes in miR-141-transfected HCC cells.

CONCLUSION

MiR-141 suppression may cause aberrant expression of SPAG9 and promote HCC tumorigenesis via JNK pathway.

Novel cancer antigens for personalized immunotherapies: latest evidence and clinical potential

The clinical success of monoclonal antibody immune checkpoint modulators such as ipilimumab, which targets cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), and the recently approved agents nivolumab and pembrolizumab, which target programmed cell death receptor 1 (PD-1), has stimulated renewed enthusiasm for anticancer immunotherapy, which was heralded by Science as 'Breakthrough of the Year' in 2013. As the potential of cancer immunotherapy has been recognized since the 1890s when William Coley showed that bacterial products could be beneficial in cancer patients, leveraging the immune system in the treatment of cancer is certainly not a new concept; however, earlier attempts to develop effective therapeutic vaccines and antibodies against solid tumors, for example, melanoma, frequently met with failure due in part to self-tolerance and the development of an immunosuppressive tumor microenvironment. Increased knowledge of the mechanisms through which cancer evades the immune system and the identification of tumor-associated antigens (TAAs) and negative immune checkpoint regulators have led to the development of vaccines and monoclonal antibodies targeting specific tumor antigens and immune checkpoints such as CTLA-4 and PD-1. This review first discusses the established targets of currently approved cancer immunotherapies and then focuses on investigational cancer antigens and their clinical potential. Because of the highly heterogeneous nature of tumors, effective anticancer immunotherapy-based treatment regimens will likely require a personalized combination of therapeutic vaccines, antibodies and chemotherapy that fit the specific biology of a patient's disease.

Targeting cancer testis antigens for biomarkers and immunotherapy in colorectal cancer: Current status and challenges

Colorectal cancer ranks third among the estimated cancer cases and cancer related mortalities in United States in 2014. Early detection and efficient therapy remains a significant clinical challenge for this disease. Therefore, there is a need to identify novel tumor associated molecules to target for biomarker development and immunotherapy. In this regard, cancer testis antigens have emerged as a potential targets for developing novel clinical biomarkers and immunotherapy for various malignancies. These germ cell specific proteins exhibit aberrant expression in cancer cells and contribute in tumorigenesis. Owing to their unique expression profile and immunogenicity in cancer patients, cancer testis antigens are clinically referred as the most promising tumor associated antigens. Several cancer testis antigens have been studied in colorectal cancer but none of them could be used in clinical practice. This review is an attempt to address the promising cancer testis antigens in colorectal cancer and their possible clinical implications as biomarkers and immunotherapeutic targets with particular focus on challenges and future interventions.