Poor Prognosis In Prostate Cancer Research Articles

High KIFC1 expression is associated with poor prognosis in prostate cancer

Kinesins play important roles in the progression and development of cancer. Kinesin family member C1 (KIFC1), a minus end-directed motor protein, is a novel Kinesin involved in the clustering of excess centrosomes found in cancer cells. Recently KIFC1 has shown to play a role in the progression of many different cancers, however, the involvement of KIFC1 in the progression of prostate cancer (PCa) is still not well understood. This study investigated the expression and clinical significance of KIFC1 in PCa by utilizing multiple publicly available datasets to analyze KIFC1 expression in patient samples. High KIFC1 expression was found to be associated with high Gleason score, high tumor stage, metastatic lesions, high ploidy levels, and lower recurrence-free survival. These results reveal that high KIFC1 levels are associated with a poor prognosis for PCa patients and could act as a prognostic indicator for PCa patients as well.

Effects of FGFR4 G388R, V10I polymorphisms on the likelihood of cancer

The correlation between G388R or V10I polymorphisms of fibroblast growth factor receptor (FGFR) 4 gene and the risk of carcinoma has been investigated previously, but the results are contradictory. Odds ratios (ORs) with 95% confidence intervals (95%CIs), in silico tools, and immunohistochemical staining (IHS) were adopted to assess the association. In total, 13,793 cancer patients and 16,179 controls were evaluated in our pooled analysis. Summarization of all the studies showed that G388R polymorphism is associated with elevated susceptibility to cancer under homozygous comparison (OR = 1.21, 95%CI = 1.03–1.43, P = 0.020) and a recessive genetic model (OR = 1.21, 95%CI = 1.04–1.41, P = 0.012). In the stratification analysis by cancer type and ethnicity, similar findings were indicated for prostate cancer, breast cancer, and individuals of Asian descendant. Polyphen2 bioinformatics analysis showed that the G388R mutation is predicted to damage the protein function of FGFR4. IHS analysis indicated that FGFR4 expression is increased in advanced prostate cancer. These findings may guide personalized treatment of certain types of cancers. Up-regulation of FGFR4 may be related to a poor prognosis in prostate cancer.

Global Histone H3 Lysine 4 Trimethylation (H3K4me3) Landscape Changes in Response to TGFβ.

TGFβ expression acts as a biomarker of poor prognosis in prostate cancer. It plays a dual functional role in prostate cancer. In the early stages of the tumor, it acts as a tumor suppressor while at the later stages of tumor development, it promotes metastasis. The molecular mechanisms of action of TGFβ are largely understood through the canonical and non-canonical signal transduction pathways. Our understanding of the mechanisms that establish transient TGFβ stimulation into stable gene expression patterns remains incomplete. Epigenetic marks like histone H3 modifications are directly linked with gene expression and they play an important role in tumorigenesis. In this report, we performed chromatin immunoprecipitation-sequencing (ChIP-Seq) to identify the genome-wide regions that undergo changes in histone H3 Lysine 4 trimethylation (H3K4me3) occupancy in response to TGFβ stimulation. We also show that TGFβ stimulation can induce acute epigenetic changes through the modulation of H3K4me3 signals at genes belonging to special functional categories in prostate cancer. TGFβ induces the H3K4me3 on its own ligands like TGFβ, GDF1, INHBB, GDF3, GDF6, BMP5 suggesting a positive feedback loop. The majority of genes were found to be involved in the positive regulation of transcription from the RNA polymerase II promoter in response to TGFβ. Other functional categories were intracellular protein transport, brain development, EMT, angiogenesis, antigen processing, antigen presentation via MHC class II, lipid transport, embryo development, histone H4 acetylation, positive regulation of cell cycle arrest, and genes involved in mitotic G2 DNA damage checkpoints. Our results link TGFβ stimulation to acute changes in gene expression through an epigenetic mechanism. These findings have broader implications on epigenetic bases of acute gene expression changes caused by growth factor stimulation.

Reduced anoctamin 7 (ANO7) expression is a strong and independent predictor of poor prognosis in prostate cancer

Objective:Anoctamin 7 (ANO7) is a calcium2+-dependent chloride ion channel protein. Its expression is restricted to prostate epithelial cells. The exact function is unknown. This study aimed to analyze ANO7 expression and its clinical significance in prostate cancer (PCa).Methods:ANO7 expression was assessed by immunohistochemistry in 17,747 clinical PCa specimens.Results:ANO7 was strongly expressed in normal prostate glandular cells but often less abundant in cancer cells. ANO7 staining was interpretable in 13,594 cancer tissues and considered strong in 34.4%, moderate in 48.7%, weak in 9.3%, and negative in 7.6%. Reduced staining was tightly linked to adverse tumor features [high classical and quantitative Gleason grade, lymph node metastasis, advanced tumor stage, high Ki67 labeling index, positive surgical margin, and early biochemical recurrence (P < 0.0001 each)]. The univariate Cox hazard ratio for prostate-specific antigen (PSA) recurrence after prostatectomy in patients with negative vs. strong ANO7 expression was 2.98 (95% confidence interval 2.61–3.38). The prognostic impact was independent of established pre- or postoperatively available parameters (P < 0.0001). Analysis of annotated molecular data showed that low ANO7 expression was linked to TMPRSS2:ERG fusions (P < 0.0001), elevated androgen receptor expression (P < 0.0001), as well as presence of 9 of 11 chromosomal deletions (P < 0.05 each). A particularly strong association of low ANO7 expression with phosphatase and tensin homolog (PTEN) deletion may indicate a functional relationship with the PTEN/AKT pathway.Conclusions:These data identify reduced ANO7 protein expression as a strong and independent predictor of poor prognosis in PCa. ANO7 measurement, either alone or in combination, might provide clinically useful prognostic information in PCa.

ACSS3 represses prostate cancer progression through downregulating lipid droplet-associated protein PLIN3.

Current endocrine therapy for prostate cancer (PCa) mainly inhibits androgen/androgen receptor (AR) signaling. However, due to increased intratumoural androgen synthesis and AR variation, PCa progresses to castration-resistant prostate cancer (CRPC), which ultimately becomes resistant to endocrine therapy. A search for new therapeutic perspectives is urgently needed.Methods: By screening lipid metabolism-related gene sets and bioinformatics analysis in prostate cancer database, we identified the key lipid metabolism-related genes in PCa. Bisulfite genomic Sequence Polymerase Chain Reaction (PCR) (BSP) and Methylation-Specific Polymerase Chain Reaction (PCR) (MSP) were preformed to detect the promoter methylation of ACSS3. Gene expression was analyzed by qRT-PCR, Western blotting, IHC and co-IP. The function of ACSS3 in PCa was measured by CCK-8, Transwell assays. LC/MS, Oil Red O assays and TG and cholesterol measurement assays were to detect the levels of TG and cholesterol in cells. Resistance to Enzalutamide in C4-2 ENZR cells was examined in a xenograft tumorigenesis model in vivo.Results: We found that acyl-CoA synthetase short chain family member 3 (ACSS3) was downregulated and predicted a poor prognosis in PCa. Loss of ACSS3 expression was due to gene promoter methylation. Restoration of ACSS3 expression in PCa cells significantly reduced LD deposits, thus promoting apoptosis by increasing endoplasmic reticulum (ER) stress, and decreasing de novo intratumoral androgen synthesis, inhibiting CRPC progression and reversing Enzalutamide resistance. Mechanistic investigations demonstrated that ACSS3 reduced LD deposits by regulating the stability of the LD coat protein perilipin 3 (PLIN3).Conclusions: Our study demonstrated that ACSS3 represses prostate cancer progression through downregulating lipid droplet-associated protein PLIN3.

Effect of obesity on the prognosis and recurrence of prostate cancer after radical prostatectomy: a meta-analysis.

BackgroundObesity has been found to be closely related to the increased risk of fatal prostate cancer (PCa), however there remains no evidence that further clarifies the relationship between obesity and the postoperative recurrence and poor prognosis of PCa. In this study, a systematic review and meta-analysis were performed to systematically evaluate the effect of obesity on the prognosis and recurrence of PCa after radical prostatectomy (RP).MethodsA literature search of the PubMed, Web of Science, and Embase databases was performed covering articles published between January 2013 and January 2020. Articles regarding the correlation between body mass index (BMI) and the prognosis and recurrence of PCa following RP were included in the meta-analysis. Two investigators independently screened the literature and extracted relevant data including publication information, key results, number of cancer cases, and multivariable-adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Meta-analysis was performed using RevMan 5.3 and Stata 16.0 software, and forest plots, funnel plots, and sensitivity analysis were also conducted.ResultsA total of 14 articles were included, all of which were analyzed for clinicopathological characteristics. Eight articles reported the biochemical recurrence (BCR) with prostate-specific antigen (PSA) as the predictor, and six articles reported the positive surgical margins (PSM). The meta-analysis showed that obese PCa patients had more postoperative recurrence and poor prognosis compared with the normal weight PCa patients, and the difference was statistically significant (OR =1.25, 95% CI: 1.10, 1.43). BCR exhibited no significant difference between obese and non-obese PCa patients after surgery (OR =1.2, 95% CI: 0.96, 1.46), and there were also no notable differences in PSM between the groups (OR =1.16, 95% CI: 0.99, 1.36). Subgroup analysis showed that obese PCa patients in the Americas (95% CI: 1.11, 1.37) and Europe (95% CI: 1.11, 1.78) were more likely to have surgical recurrence and poor prognosis (OR =1.40). Obese patients in the Americas were also more likely to have BCR after surgery (95% CI: 1.07, 1.36).ConclusionsObesity easily leads to poor prognosis and recurrence of PCa after RP.

Epithelial splicing regulatory protein 1 and 2 (ESRP1 and ESRP2) upregulation predicts poor prognosis in prostate cancer

BackgroundEpithelial splicing regulatory protein 1 (ESRP1) and 2 (ESRP2) regulate alternative splicing events of various pre-mRNAs. Some of these targets play a role in cancer-associated processes, including cytoskeleton reorganization and DNA-repair processes. This study was undertaken to estimate the impact of ESRP1 and ESRP2 alterations on prostate cancer patient prognosis.MethodsA tissue microarray made from 17,747 individual cancer samples with comprehensive, pathological, clinical and molecular data was analyzed by immunohistochemistry for ESRP1 and ESRP2.ResultsNuclear staining for ESRP1 was seen in 38.6% (36.0% low, 2.6% high) of 12,140 interpretable cancers and in 41.9% (36.4% low, 5.3% high) of 12,962 interpretable cancers for ESRP2. Nuclear protein expression was linked to advanced tumor stage, high Gleason score, presence of lymph node metastasis, early biochemical recurrence, and ERG-positive cancers (p < 0.0001 each). Expression of ESRPs was significantly linked to 11 (ESRP1)/9 (ESRP2) of 11 analyzed deletions in all cancers and to 8 (ESRP1)/9 (ESRP2) of 11 deletions in ERG-negative cancers portending a link to genomic instability. Combined ESRPs expression analysis suggested an additive effect and showed the worst prognosis for cancers with high ESRP1 and ESRP2 expression. Multivariate analyses revealed that the prognostic impact of ESRP1, ESRP2 and combined ESRP1/ESRP2 expression was independent of all established pre- and postoperative prognostic features.ConclusionsOur data show a striking link between nuclear ESRP expression and adverse features in prostate cancer and identifies expression of ESRP1 and/or ESRP2 as independent prognostic markers with a potential for routine application.

Inhibition of EZH2 Enhances the Antitumor Efficacy of Metformin in Prostate Cancer.

Upregulation of EZH2 is associated with advanced stage and poor prognosis of prostate cancer; therefore, it is likely to be a promising therapeutic target. Metformin, a drug that has been used to treat type 2 diabetes, was found to have antineoplastic activity in different cancers. Herein, we report that the combination of metformin and the EZH2 inhibitor GSK126 exerts synergistic inhibition on prostate cancer cell growth, both in vitro and in vivo Mechanistically, we identify that metformin can reduce EZH2 expression through upregulating miR-26a-5p, which is antagonized by androgen receptor (AR). Furthermore, we show that AR binds to the promoter of miR-26a-5p and suppresses its transcription. Although metformin can remove AR from the miR-26a-5p promoter, the interaction between AR and EZH2, which usually exists in androgen-refractory prostate cancer cells, strongly impedes the removal. However, GSK126 can inhibit the methyltransferase-dependent interaction between AR and EZH2, thus restoring metformin's efficacy in androgen-refractory prostate cancer cells. Collectively, our finding suggests that the combination of metformin and GSK126 would be an effective approach for future prostate cancer therapy, and particularly effective for AR-positive castration-resistant prostate cancer.

MiRNA-671-5p Promotes prostate cancer development and metastasis by targeting NFIA/CRYAB axis

Prostate cancer (PCa) is the second cause of death due to malignancy among men, and metastasis is the leading cause of mortality in patients with PCa. MicroRNAs (miRNAs) play important regulatory roles in tumor development and metastasis. Here, we identified 13 miRNAs related to PCa metastasis by bioinformatics analysis. Moreover, we found that miR-671-5p was increased in metastatic PCa tissues, and its high expression indicated poor prognosis of PCa. MiR-671-5p could facilitate PCa cells proliferation, migration, and invasion in vitro and vivo. We confirmed that miR-671-5p directly bound to the 3’ untranslated regions of NFIA mRNA, and NFIA directly bound to the CRYAB promoter. High expression of NFIA and CRYAB negatively correlated with the advanced clinicopathological characteristics and metastasis status of PCa patients. Our study demonstrated that miR-671-5p promoted PCa development and metastasis by suppressing NFIA/ CRYAB axis.

Increased Cytoplasmic CD138 Expression Is Associated with Aggressive Characteristics in Prostate Cancer and Is an Independent Predictor for Biochemical Recurrence.

Syndecan-1 (CD138) is a transmembrane proteoglycan expressed in various normal and malignant tissues. It is of interest due to a possible prognostic effect in tumors and its role as a target for the antibody-drug conjugate indatuximab ravtansine. Here, we analyzed 17,747 prostate cancers by immunohistochemistry. Membranous and cytoplasmic CD138 staining was separately recorded. In normal prostate glands, CD138 staining was limited to basal cells. In cancers, membranous CD138 positivity was seen in 19.6% and cytoplasmic CD138 staining in 11.2% of 12,851 interpretable cases. A comparison with clinico-pathological features showed that cytoplasmic CD138 staining was more linked to unfavorable tumor features than membranous staining. Cytoplasmic CD138 immunostaining was associated with high tumor stage (p < 0.0001), high Gleason grade (p < 0.0001), nodal metastases (p < 0.0001), positive surgical margin (p < 0.0001), and biochemical recurrence (p < 0.0001). This also holds true for both V-ets avian erythroblastosis virus E26 oncogene homolog (ERG) fusion positive and ERG fusion negative tumors although the cytoplasmic CD138 expression was markedly more frequent in ERG positive than in ERG negative tumors (p < 0.0001). Comparison with 11 previously analyzed chromosomal deletions identified a conspicuous association between cytoplasmic CD138 expression and 8p deletions (p < 0.0001) suggesting a possible functional interaction of CD138 with one or several 8p genes. Multivariate analysis revealed the cytoplasmic CD138 expression as an independent prognostic parameter in all cancers and in the ERG positive subgroup. In summary, our study indicates the cytoplasmic CD138 expression as a strong and independent predictor of poor prognosis in prostate cancer. Immunohistochemical measurement of CD138 protein may thus—perhaps in combination with other parameters—become clinically useful in the future.

Genome-wide gene expression analysis of a murine model of prostate cancer progression: Deciphering the roles of IL-6 and p38 MAPK as potential therapeutic targets.

BackgroundProstate cancer (PCa) is the most commonly diagnosed cancer and the second leading cause of cancer-related deaths among adult males globally. The poor prognosis of PCa is largely due to late diagnosis of the disease when it has already progressed to an advanced stage marked by androgen-independence, thus necessitating new strategies for early detection and treatment. We construe that these direly needed advances are limited by our poor understanding of early events in the progression of PCa and that would thus represent ideal targets for early intervention. To begin to fill this void, we interrogated molecular “oncophenotypes” that embody the transition of PCa from an androgen-dependent (AD) to–independent (AI) state.MethodsTo accomplish this aim, we used our previously established AD and AI murine PCa cell lines, PLum-AD and PLum-AI, respectively, which recapitulate primary and progressive PCa morphologically and molecularly. We statistically surveyed global gene expressions in these cell lines by microarray analysis. Differential profiles were functionally interrogated by pathways, gene set enrichment and topological gene network analyses.ResultsGene expression analysis of PLum-AD and PLum-AI transcriptomes (n = 3 each), revealed 723 differentially expressed genes (392 upregulated and 331 downregulated) in PLum-AI compared to PLum-AD cells. Gene set analysis demonstrated enrichment of biological functions and pathways in PLum-AI cells that are central to tumor aggressiveness including cell migration and invasion facilitated by epithelial-to-mesenchymal transition (EMT). Further analysis demonstrated that the p38 mitogen-activated protein kinase (MAPK) was predicted to be significantly activated in the PLum-AI cells, whereas gene sets previously associated with favorable response to the p38 inhibitor SB203580 were attenuated (i.e., inversely enriched) in the PLum-AI cells, suggesting that these aggressive cells may be therapeutically vulnerable to p38 inhibition. Gene set and gene-network analysis also alluded to activation of other signaling networks particularly those associated with enhanced EMT, inflammation and immune function/response including, but not limited to Tnf, IL-6, Mmp 2, Ctgf, and Ptges. Accordingly, we chose SB203580 and IL-6 to validate their effect on PLum-AD and PLum-AI. Some of the common genes identified in the gene-network analysis were validated at the molecular and functional level. Additionally, the vulnerability to SB203580 and the effect of IL-6 were also validated on the stem/progenitor cell population using the sphere formation assay.ConclusionsIn summary, our study highlights pathways associated with an augmented malignant phenotype in AI cells and presents new high-potential targets to constrain the aggressive malignancy seen in the castration-resistant PCa.

Protein Expression Analysis of an In Vitro Murine Model of Prostate Cancer Progression: Towards Identification of High-Potential Therapeutic Targets.

Background: Prostate cancer (PC) is the most frequently diagnosed cancer among men worldwide. The poor prognosis of PC is largely due to late diagnosis of the disease when it has progressed to advanced stages marked by androgen-independence. We interrogated proteomic signatures that embody the transition of PC from an androgen-dependent (AD) to an androgen-independent (AI) state. Methods: We have previously established AD and AI murine PC cell lines, PLum-AD and PLum-AI, respectively, which recapitulate primary and progressive PC at phenotypic and subcellular levels. We statistically surveyed global protein expression profiles in these cell lines. Differential profiles were functionally interrogated by pathways and protein–protein interaction network analyses. Results: Protein expression pattern analysis revealed a total of 683 proteins, among which 99 were significantly differentially altered in PLum-AI cells as compared to PLum-AD cells (45 increased and 54 decreased). Principal component analysis (PCA) revealed that the two different cell lines clearly separated apart, indicating a significant proteome expression difference between them. Four of the proteins (vimentin, catalase, EpCAM, and caspase 3) that were differentially expressed in PLum-AI cells compared to PLum-AD cells were subjected to biochemical validation by Western blotting. Biological process gene ontology (GO) analysis of the differentially expressed proteins demonstrated enrichment of biological functions and pathways in PLum-AI cells that are central to PI3 kinase and androgen receptor pathways. Besides, other relevant biological processes that are enriched in PLum-AI cells included cell adhesion and cell migration processes, cell and DNA damage, apoptosis, and cell cycle regulation. Conclusions: Our protein expression analysis of a murine in vitro model of PC progression identified differential protein spots that denote this progression and that comprise high-potential targets for early treatment of PC with a personalized patient-specific approach. Efforts are underway to functionally assess the potential roles of these proteins as therapeutic targets for PC progression.

SHCBP1 promotes tumor cell proliferation, migration, and invasion, and is associated with poor prostate cancer prognosis.

Prostate cancer (PCa) is an aggressive tumor. SHC SH2-domain-binding protein 1 (SHCBP1) has been identified frequently upregulated in various cancers, in addition to PCa. The aims of this study were to determine the relationships between SHCBP1 and clinicopathological characteristics of PCa and to explore the role of SHCBP1 in PCa proliferation and progression. Tissue microarray and immunohistochemistry were used to determine the prognostic significance of SHCBP1. The relationship between clinicopathological characteristics of PCa and SHCBP1 was then analyzed using Cox regression analyses. To investigate SHCBP1 functions in vitro and in vivo, we knocked down SHCBP1 in PCa cell lines and established xenograft mice models. A series of cytological function assays were utilized to determine the role of SHCBP1 in cell proliferation, migration, invasion, and apoptosis. SHCBP1 was significantly upregulated in PCa tissues compared with BPH tissues. Patients with a higher expression of SHCBP1 were associated with poor survival outcomes than those with a lower expression of SHCBP1. Lentivirus-mediated shRNA knockdown of SHCBP1 in prostate cancer cell lines diminished cell growth, migration, and invasion dramatically both in vitro and in vivo, accompanied by an enhanced expression of large tumor suppressor 1 (LATS1) and tumor protein P53 (TP53) and inhibition of MDM2 proto-oncogene (MDM2), which suggested that SHCBP1 may promote proliferation and invasion in vitro via the LATS1-MDM2-TP53 pathway. The results of cycloheximide (CHX) and MG-132 assays indicated that SHCBP1 knockdown could attenuate the degradation of TP53 by the proteasome, prolong the half-life of TP53, and enhance the stabilization of TP53. These findings suggest that SHCBP1 overexpression contributes to PCa progression and that targeting SHCBP1 might be therapeutically beneficial to patients with PCa.

Upregulation of Phosphatase 1 Nuclear-Targeting Subunit (PNUTS) Is an Independent Predictor of Poor Prognosis in Prostate Cancer.

Protein phosphatase 1 nuclear-targeting subunit (PNUTS) is ubiquitously expressed and associates with PTEN and protein phosphatase 1 (PP1) to control its activity. The role of PNUTS overexpression has hardly been studied in cancer. In this study, we used immunohistochemistry to quantitate PNUTS expression on a tissue microarray containing 17,747 clinical prostate cancer specimens. As compared to normal prostate epithelium, PNUTS expression was often higher in cancer. Among 12,235 interpretable tumors, PNUTS staining was negative in 21%, weak in 34%, moderate in 35%, and strong in 10% of cases. High PNUTS expression was associated with higher tumor stage, classical and quantitative Gleason grade, nodal stage, surgical margin, Ki67 labeling index, and early biochemical recurrence (p < 0.0001 each). PNUTS expression proved to be a moderate prognostic parameter with a maximal univariable Cox proportional hazard for PSA recurrence-free survival of 2.21 compared with 5.91 for Gleason grading. It was independent from established prognostic parameters in multivariable analysis. Comparison with molecular data available from earlier studies using the same TMA identified associations between high PNUTS expression and elevated androgen receptor expression (p < 0.0001), presence of TMPRSS2:ERG fusion (p < 0.0001), and 8 of 11 chromosomal deletions (3p13, 5q21, 8p21, 10q23, 12p13, 13q14, 16q24, and 17p13; p < 0.05 each). Particularly strong associations with PTEN and 12p13 deletions (p < 0.0001 each) may indicate a functional relationship, which has already been established for PNUTS and PTEN. PNUTS had no additional role on outcome in PTEN-deleted cancers. In conclusion, the results of our study identify high PNUTS protein levels as a predictor of poor prognosis possibly linked to increased levels of genomic instability. PNUTS measurement, either alone or in combination, might be of clinical utility in prostate cancers.

Upregulation of PTTG1 is associated with poor prognosis in prostate cancer.

Pituitary tumor-transforming gene 1 (PTTG1) is a regulator of chromosome stability. PTTG1 overexpression had been associated with tumor aggressiveness in several cancer types. To examine its prognostic utility in prostate cancer, a tissue microarray including 12 427 tumors with clinical and molecular data was analyzed by immunohistochemistry. PTTG1 immunostaining was largely absent in normal prostate epithelial cells. In cancers, staining was considered weak in 5.4%, moderate in 5.6% and strong in 0.8%. Strong staining was linked to advanced pT stage, high classical and quantitative Gleason grade, high Ki67-labeling index (all P < 0.0001) and lymph node metastasis (P = 0.0083). The prognostic impact of PTTG1 expression was independent of established preoperative and postoperative prognostic features. Comparison with molecular features revealed that PTTG1 upregulation was associated with nine of 12 common genomic deletions (P < 0.05), p53 alterations and high androgen receptor levels (P < 0.001 each), but was unrelated to the TMPRSS2:ERG fusion status. In conclusion, these data identify PTTG1 as a strong and independent prognostic feature in prostate cancer. PTTG1 measurement, either alone or in combination with other biomarkers might be instrumental for determining prostate cancer aggressiveness.

Overexpression of SLC6A1 associates with drug resistance and poor prognosis in prostate cancer

BackgroundSolute Carrier Family 6 Member 1 (SLC6A1) has been identified as a cancer-promoting gene in various human cancers, such as clear cell renal cell carcinoma and ovarian cancer. However, its roles in prostate cancer (PCa) has not been fully elucidated. The aim of this study was to investigate the expression and clinical significance of SLC6A1 in PCa tissues and its effect on drug resistance to docetaxel in PCa.MethodsExpression patterns of SLC6A1 protein in PCa tissues were examined by immunohistochemistry based on Tissue microarray. Associations of SLC6A1 protein expression with various clinicopathological features and patients’ prognosis of PCa were also statistically evaluated based on TCGA data. Roles of SLC6A1 deregulation in prostate carcinogenesis and drug resistance was further determined in vitro and in vivo experiments.ResultsBased on TCGA Dataset, SLC6A1 expression was markedly higher in patients with high Gleason score, advanced clinical stage and positive biochemical recurrence than those with control features (all P < 0.05). Both unvariate and multivariate analyses demonstrated that SLC6A1 expression was significantly associated with biochemical recurrence-free survival in PCa patients. In addition, enforced expression of SLC6A1 effectively promoted cell proliferation, migration and invasion of PCa cells in vitro. Moreover, the inhibition of SLC6A1 suppressed the tumor growth in vivo. Additionally, immunohistochemical notches of PCNA and MMP-9 in the low-expression cluster were pointedly lower compared to those of NC group. Finally, the cell viability revealed that the overexpression of SLC6A1 obviously promoted the PCa cell resistant to docetaxel (DTX), and the transplanted tumor in the overexpression group had no significant reduction compared with the untreated group.ConclusionsOur data suggest that SLC6A1 overexpression may be associated with aggressive progression and short biochemical recurrence-free survival of PCa, and may be related to the resistance to docetaxel therapy.

Loss of the adhesion molecule CEACAM1 is associated with early biochemical recurrence in TMPRSS2:ERG fusion-positive prostate cancers.

Altered expression of the carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) has been linked to adverse tumor features in various cancer types. To better understand the role of CEACAM1 in prostate cancer, we analyzed a tissue microarray containing tumor spots from 17,747 prostate cancer patients by means of immunohistochemistry. Normal prostate glands showed intense membranous CEACAM1 positivity. Immunostaining was interpretable in 13,625 cancers and was considered high in 28%, low in 43% and absent in 29% of tumors. Low and lost CEACAM1 expression was strongly linked to adverse tumor features including high classical and quantitative Gleason grade, lymph node metastasis, advanced tumor stage, positive surgical margin, a high number of genomic deletions and early biochemical recurrence (p < 0.0001 each). Subset analysis of molecularly defined cancer subsets revealed that these associations were strongest in V-ets avian erythroblastosis virus E26 oncogene homolog (ERG) fusion-positive cancers and that CEACAM1 loss was prognostic even in tumors harboring genomic deletions of the phosphatase and tensin homolog tumor suppressor (p < 0.0001). Multivariate analysis suggested that CEACAM1 analysis can provide independent prognostic information beyond established prognosis parameters at the stage of the initial biopsy when therapy decisions must be taken. In conclusion, loss of CEACAM1 expression predicts poor prognosis in prostate cancer and might provide clinically useful prognostic information particularly in cancers harboring the TMPRSS2:ERG fusion.

HO-1 Interactors Involved in the Colonization of the Bone Niche: Role of ANXA2 in Prostate Cancer Progression.

Background: Prostate cancer (PCa) dissemination shows a tendency to develop in the bone, where heme oxygenase 1 (HO-1) plays a critical role in bone remodeling. Previously by LC/ESI-MSMS, we screened for HO-1 interacting proteins and identified annexin 2 (ANXA2). The aim of this study was to analyze the relevance of ANXA2/HO-1 in PCa and bone metastasis. Methods: We assessed ANXA2 levels using a co-culture transwell system of PC3 cells (pre-treated or not with hemin, an HO-1 specific inducer) and the pre-osteoclastic Raw264.7 cell line. Results: Under co-culture conditions, ANXA2 mRNA levels were significantly modulated in both cell lines. Immunofluorescence analysis unveiled a clear ANXA2 reduction in cell membrane immunostaining for Raw264.7 under the same conditions. This effect was supported by the detection of a decrease in Ca2+ concentration in the conditioned medium. HO-1 induction in tumor cells prevented both, the ANXA2 intracellular relocation and the decrease in Ca2+ concentration. Further, secretome analysis revealed urokinase (uPA) as a key player in the communication between osteoclast progenitors and PC3 cells. To assess the clinical significance of ANXA2/HO-1, we performed a bioinformatics analysis and identified that low expression of each gene strongly associated with poor prognosis in PCa regardless of the clinico-pathological parameters assessed. Further, these genes appear to behave in a dependent manner. Conclusions: ANXA2/HO-1 rises as a critical axis in PCa.

The Oncogenic Potential of the Centromeric Border Protein FAM84B of the 8q24.21 Gene Desert.

FAM84B is a risk gene in breast and prostate cancers. Its upregulation is associated with poor prognosis of prostate cancer, breast cancer, and esophageal squamous cell carcinoma. FAM84B facilitates cancer cell proliferation and invasion in vitro, and xenograft growth in vivo. The FAM84B and Myc genes border a 1.2 Mb gene desert at 8q24.21. Co-amplification of both occurs in 20 cancer types. Mice deficient of a 430 Kb fragment within the 1.2 Mb gene desert have downregulated FAM84B and Myc expressions concurrent with reduced breast cancer growth. Intriguingly, Myc works in partnership with other oncogenes, including Ras. FAM84B shares similarities with the H-Ras-like suppressor (HRASLS) family over their typical LRAT (lecithin:retinal acyltransferase) domain. This domain contains a catalytic triad, H23, H35, and C113, which constitutes the phospholipase A1/2 and O-acyltransferase activities of HRASLS1-5. These enzymatic activities underlie their suppression of Ras. FAM84B conserves H23 and H35 but not C113 with both histidine residues residing within a highly conserved motif that FAM84B shares with HRASLS1-5. Deletion of this motif abolishes FAM84B oncogenic activities. These properties suggest a collaboration of FAM84B with Myc, consistent with the role of the gene desert in strengthening Myc functions. Here, we will discuss recent research on FAM84B-derived oncogenic potential.

Identification of PTPRR and JAG1 as key genes in castration-resistant prostate cancer by integrated bioinformatics methods.

To identify novel genes in castration-resistant prostate cancer (CRPC), we downloaded three microarray datasets containing CRPC and primary prostate cancer in Gene Expression Omnibus (GEO). R packages affy and limma were performed to identify differentially expressed genes (DEGs) between primary prostate cancer and CRPC. After that, we performed functional enrichment analysis including gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway. In addition, protein-protein interaction (PPI) analysis was used to search for hub genes. Finally, to validate the significance of these genes, we performed survival analysis. As a result, we identified 53 upregulated genes and 58 downregulated genes that changed in at least two datasets. Functional enrichment analysis showed significant changes in the positive regulation of osteoblast differentiation pathway and aldosterone-regulated sodium reabsorption pathway. PPI network identified hub genes like cortactin-binding protein 2 (CTTNBP2), Rho family guanosine triphosphatase (GTPase) 3 (RND3), protein tyrosine phosphatase receptor-type R (PTPRR), Jagged1 (JAG1), and lumican (LUM). Based on PPI network analysis and functional enrichment analysis, we identified two genes (PTPRR and JAG1) as key genes. Further survival analysis indicated a relationship between high expression of the two genes and poor prognosis of prostate cancer. In conclusion, PTPRR and JAG1 are key genes in the CRPC, which may serve as promising biomarkers of diagnosis and prognosis of CRPC.