WASP and WAVE proteins: vital intrinsic regulators of cell motility and their role in cancer (Review)

Cell migration is critical during the metastatic spread of cancer cells. Metastases, rather than primary tumours, are responsible for most cancer-related deaths. Invasive cancer cells acquire a migratory phenotype which is associated with an increased expression of several genes involved in cell motility. Actin, which is the most abundant protein in most eukaryotic cells, is necessary for whole cell locomotion. Reorganisation of actin filaments is regulated by a highly integrated signalling cascade governed by ‘molecular switches’ which belong to the Rho GTPase family. WASP family proteins are downstream molecules which form a link between the GTPases and the actin cytoskeleton. The WASP family includes 5 members and is structurally divided into 2 groups: Wiskott-Aldrich Syndrome proteins (WASPs) and WASP verprolin homologous proteins (WAVEs). Current evidence suggests that WAVEs are crucial for cell motility and metastasis. This is a review on the possible role of WAVEs in cancer and the clinical associations found in human cancer

Analysis of Fascin-1 in Relation to Gleason Risk Classification and Nuclear ETS-Related Gene Status of Human Prostate Carcinomas:An Immunohistochemical Study of Clinically Annotated Tumours From the Wales Cancer Bank

Although prostate-specific antigen (PSA) testing can identify early-stage prostate cancers, additional biomarkers are needed for risk stratification. In one study, high levels of the actin-bundling protein, fascin-1, were correlated with lethal-phase, hormone-refractory prostate cancer. Analyses of independent samples are needed to establish the value of fascin-1 as a possible biomarker. We examined fascin-1 by immunohistochemistry in tumour specimens from the Wales Cancer Bank in comparison with nuclear-located ETS-related gene (ERG), an emerging marker for aggressive prostate cancer. Fascin-1 was elevated in focal areas of a minority of tumours, yet fascin-1-positivity did not differentiate tumours of low-, intermediate-, or high-risk Gleason scores and did not correlate with PSA status or biochemical relapse after surgery. Stromal fascin-1 correlated with high Gleason score. Nuclear ERG was upregulated in tumours but not in stroma. The complexities of fascin-1 status indicate that fascin-1 is unlikely to provide a suitable biomarker for prediction of aggressive prostate cancer

Repulsive guidance molecules, novel bone morphogenetic protein co-receptors, are key regulators of the growth and aggressiveness of prostate cancer cells

Repulsive guidance molecule (RGM) family members RGMA, RGMB and RGMC are GPI-linked membrane proteins recently identified as co-receptor of bone morphogenetic proteins (BMPs). BMPs are a group of proteins enriched in bone and play important roles in prostate cancer. The current study aimed to investigate roles played by RGMs in prostate cancer. Expression of RGMs was examined in prostate cancer cell lines and prostate cancer tissues using RT-PCR and immunohistochemical staining. Knockdown of each RGM in prostate cancer cells was performed using the respective anti-RGMA, RGMB and RGMC transgenes. A variety of in vitro function tests were employed to analyze the influence on cancer cell functions by RGM knockdown. The implications of RGM knockdown in BMP signalling were also examined using both Western blot and real-time quantitative PCR. Knockdown of RGMA had no effect on cell growth, migration and invasion, but promoted cell-matrix adhesion. Knockdown of RGMB and RGMC increased growth and adhesion, but only RGMB knockdown increased capacities of migration and invasion in PC-3 cells. Further investigations showed an increase in Smad-3 activation and reduced levels of Smad-1 in PC-3 cells by RGMB and RGMC knockdown, and also an up-regulation of ID1, a BMP target gene particularly in exposure to BMP7. RGMs play inhibitory roles in prostate cancer by suppressing cell growth, adhesion, migration and invasion. RGMs can coordinate Smad-dependent signalling of BMPs in prostate cancer cells

Growth and differentiation factor-9 promotes adhesive and motile capacity of prostate cancer cells by up-regulating FAK and Paxillin via Smad dependent pathway

The majority of advanced prostate cancers metastasise to the bone. Mediators of bone remodelling, the bone morphogenetic proteins have extensively been implicated in the progression and metastasis of prostate cancer. The present study investigated the function of BMP member GDF-9, in prostate cancer. We overexpressed GDF9 in PC-3 cells using a mammalian expression construct, and knocked-down with the use of ribozyme transgenes. These cells were further used in in vitro adhesion and motility assays, in order to determine the effect of GDF-9 on these properties. Recombinant GDF-9 was generated to treat PC-3 WT cells before further analysing the effect on adhesion. The GDF-9 overexpressing PC-3 cells demonstrated a significantly enhanced adhesive and motile capacity compared to their controls. The opposite effect was seen in the GDF-9 knock-down cells. In addition, treating PC-3 cells with rh-GDF-9 resulted in them becoming more adhesive. Both endogenous and exogenous GDF-9 was demonstrated to up-regulate focal adhesion associated proteins FAK and paxillin which contribute to promoted cell adhesion and motility. With the use of a Smad3 inhibitor, this effect was inhibited suggesting that GDF-9 signals via Smad3 to up-regulate expression of these proteins. This study shows that GDF-9 can promote the motile and adhesive capacity of PC-3 prostate cancer cells by up-regulating expression of FAK and paxillin in a Smad dependent manner, suggesting a pro-tumourigenic role for GDF-9 in prostate cancer

Pathological upgrading in prostate cancer treated with surgery in the United Kingdom: trends and risk factors from the British Association of Urological Surgeons Radical Prostatectomy Registry

Background Accurate grading at the time of diagnosis if fundamental to risk stratification and treatment decision making in patients with prostate cancer. Whilst previous studies have demonstrated significant pathological upgrading and downgrading following radical prostatectomy (RP), these were based on historical cohorts and do not reflect contemporary patient selection and management practices. The aim of this national, multicentre observational study was to characterise contemporary rates and risk factors for pathological upgrading after RP in the United Kingdom (UK). Methods All RP entries on the British Association of Urological Surgeons (BAUS) Radical Prostatectomy Registry database of prospectively entered cases undertaken between January 2011 and December 2016 were extracted. Those patients with full preoperative PSA, clinical stage, needle biopsy and subsequent RP pathological grade information were included. Upgrade was defined as any increase in Gleason grade from initial needle biopsy to pathological assessment of the entire surgical specimen. Statistical analysis and multivariate logistic regression were undertaken using R version 3.5 (R Foundation for Statistical Computing, Vienna, Austria). Results A total of 17,598 patients met full inclusion criteria. Absolute concordance between initial biopsy and pathological grade was 58.9% (n = 10,364), whilst upgrade and downgrade rates were 25.5% (n = 4489) and 15.6% (n = 2745) respectively. Upgrade rate was highest in those with D’Amico low risk compared with intermediate and high-risk disease (55.7% versus 19.1 and 24.3% respectively, P < 0.001). Although rates varied between year of surgery and geographical regions, these differences were not significant after adjusting for other preoperative diagnostic variables using multivariate logistic regression. Conclusions Pathological upgrading after RP in the UK is lower than expected when compared with other large contemporary series, despite operating on a generally higher risk patient cohort. As new diagnostic techniques that may reduce rates of pathological upgrading become more widely utilised, this study provides an important benchmark against which to measure future performance

Vascular endothelial growth inhibitor, expression in human prostate cancer tissue and the impact on adhesion and migration of prostate cancer cells in vitro

Vascular endothelial growth inhibitor (VEGI) has been associated with tumour-related vasculature in certain maligancies. However, its implication in prostate cancer remains unknown. We investigated the expression pattern and role of VEGI in prostate cancer and prostate cancer cells. The expression of VEGI was examined in human prostate tissue and prostate cancer cell lines. The biological impact of modifying the expression of VEGI in prostate cancer cells was evaluated using in vitro models. VEGI mRNA was expressed in a wide variety of human prostate cancer cell lines and most prostate specimens. VEGI protein was seen in normal prostate epithelium, but was decreased or absent in prostate cancer specimens, particularly in tumours with high Gleason scores. Moreover, forced-expression of VEGI led to a decrease in the motility and adhesion of prostate cancer cells in vitro. In contrast, knocking down VEGI in the cells resulted in an increase in motility and adhesion. Interestingly, both forced-expression and knocking down of VEGI had no bearing on growth and invasive capacity of prostate cells. In conclusion, the expression of VEGI is decreased in prostate cancer and is almost absent in tumours with high Gleason scores. Together with its inhibitory effect on cellular motility and adhesion, this suggests that VEGI functions as a negative regulator for aggressiveness during the development and progression of prostate cancer

The prostate transglutaminase, TGase-4, coordinates with the HGFL/MSP-RON system in stimulating the migration of prostate cancer cells

The prostate transglutaminase, TGase-4, is a member of the transglutaminase family and is uniquely expressed in the prostate gland. The function of the protein is largely unknown, although an influence on cell motility and adhesion has been indicated. The present study investigated the impact of the differential expression of TGase-4 in human prostate cancer cells on RON, the hepatocyte growth factor-like/macrophage-stimulating protein (HGF-L/MSP) receptor, mediated cellular functions. Using human prostate cancer cell lines and prostate tissues, we demonstrated that human TGase-4 had a high degree of co-localisation with RON, primarily at the cell periphery and cell-cell adhesion region. High levels of TGase-4 expression in CAHPV10 cells and in PC3 cells engineered to over-express TGase-4 were associated with significantly increased cell motility in response to HGF-L, a clear contrast to wild-type and control cells. Neutralising antibody to RON and rhHGFL/MSP had no further bearing on the increased motility in TGase-4 over-expressing cells, although they had profound effect on the control cells. Akt pathway inhibitor significantly diminished the effect induced by HGF-L in the cells. Finally, over-expression of TGase-4 in prostate cancer cells resulted in autophosphorylation of RON. It is concluded that TGase-4 expression is intrinsically linked to the activation of RON in prostate cancer cells and that this autoactivation of RON contributes to the increased cell motility in TGase-4 expressing cells

Cyclo-oxygenase-2 expression is associated with mean standardised uptake value on 18F-fluorodeoxyglucose positron emission tomography in oesophageal adenocarcinoma

OBJECTIVES: This pilot study investigated the association of four PET image features and cyclo-oxygenase-2 (COX-2) expression in patients with oesophageal adenocarcinoma. The prognostic significance of these biomarkers was also assessed. METHODS: 50 consecutive patients [median age = 68 (range 47 – 84), males = 45) with oesophageal adenocarcinoma had PET/CT staging between January 2011 and July 2015. The maximum and mean standardised uptake values (SUVmax and SUVmean), metabolic tumour volume (MTV) and tumour lesion glycolysis (TLG) were calculated from the primary tumour. Their association with COX-2 status was assessed using Mann-Whitney U tests. Kaplan-Meier and Cox regression analysis tested their prognostic significance. A p-value < 0.05 was considered statistically significant. RESULTS: 32 tumours (64.0%) were COX-2 positive. There was a significant association between SUVmean and COX-2 status (p = 0.019). TLG (hazard ratio (HR) 1.001, 95 % confidence intervals (CI) 1.000 – 1.002, p = 0.018) was significantly associated with overall survival on multivariable analysis. CONCLUSIONS: This study investigated the association between PET image features and COX-2 expression in oesophageal adenocarcinoma. The preliminary results signal that a combination of TLG (calculated as product of MTV and SUVmean) and COX-2 status may be a strong and clinically important prognostic biomarker. Our research group are planning a prospective, multi-centre study to validate these findings. ADVANCES IN KNOWLEDGE: Mean standardised uptake value (SUVmean) on PET imaging is associated with COX-2 expression in oesophageal adenocarcinoma

Expression of the ERM family members (ezrin, radixin and moesin) in breast cancer

The ERM family is composed of the proteins ezrin, moesin and radixin, which are cell structure-related proteins. Despite the detection of viable roles of ERM family proteins, the impact of these molecules in cancer pathogenesis has yet to be investigated. Evidence emerging from clinical and translational studies showed that the ERM family is linked to disease progression in clinical cancers. We aimed to establish the pattern of expression of the ERM proteins and deduce a possible relationship between these molecules and clinical outcome in a cohort of human breast cancers. The expression of the three ERM molecules at the mRNA and protein levels in a cohort of 122 human breast cancers and 32 normal breast tissues were analysed and correlated with pathological and clinical information as well as patient outcome. The three molecules were positively stained in mammary tissues while the staining pattern was lost in the malignant cells. Low levels of moesin and radixin transcripts were seen in tumours from patients with metastasis, local recurrence and in patients who succumbed to the disease (moesin: p=0.039, p=0.037 and p=0.066, respectively, and radixin: p=0.039, p=0.039 and p=0.04, respectively). Ezrin levels were significantly lower in tumour recurrence and in patients who succumbed to the disease (p=0.0001 and p=0.59, respectively). Using the Kaplan-Meier survival analysis, a general trend of higher levels of ERM was observed, with marginal long overall and disease-free survival. In conclusion, an inverse relationship between ERM expression and tumour behaviour of breast cancer patients was noted. However, further work needs to be conducted in other types of cancer in clinical situations to obtain consistent results

Utilisation of the STEAP protein family in a diagnostic setting may provide a more comprehensive prognosis of prostate cancer

Prostate cancer is the second most common cancer diagnosed in men worldwide; however, few patients are affected by clinically significant disease within their lifetime. Unfortunately, the means to discriminate between patients with indolent disease and those who progress to aggressive prostate cancer is currently unavailable, resulting in over-treatment of patients. We therefore aimed to determine biomarkers of prostate cancer that can be used in the clinic to aid the diagnosis and prognosis. Immunohistochemistry analysis was carried out on prostate cancer specimens with a range of Gleason scores. Samples were stained and analysed for intensity of the Seven Transmembrane Epithelial Antigen of the Prostate (STEAP)-1, -2, -3, -4 and the Divalent Metal Transporter 1 (DMT1) proteins to determine suitable biomarkers for classification of patients likely to develop aggressive prostate cancer. Additionally, these proteins were also analysed to determine whether any would be able to predict future relapse using Kaplan Meier analysis. Data generated demonstrated that the protein expression levels of STEAP2 correlated significantly with Gleason score; furthermore, STEAP4 was a significant predictor of relapse. This data indicates that STEAP2 could be potential prognostic candidate for use in combination with the current prostate cancer detection methods and the presence of STEAP4 could be an indicator of possible relapse