Elevated levels of tumour apolipoprotein D independently predict poor outcome in breast cancer patients.

AIMS: Apolipoprotein D (ApoD) is a protein that is regulated by androgen and oestrogen, and is a major constituent of breast cysts. Although ApoD has been reported to be a marker of breast cancer, its prognostic importance in invasive breast cancer is unclear. The aim of this study was to investigate the relationship between ApoD protein expression, oestrogen receptor-α (ERα) expression and androgen receptor (AR) expression in predicting breast cancer outcome. METHODS AND RESULTS: ApoD levels were measured by the use of immunohistochemistry and video image analysis on tissue sections from a breast cancer cohort (n = 214). We assessed the associations of ApoD expression with disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS). We also assessed the relationship between ApoD expression, AR expression and ERα expression in predicting OS. ApoD expression (>1% ApoD positivity) was found in 72% (154/214) of tissues. High ApoD positivity (≥20.7%, fourth quartile) was an independent predictor of MFS and OS, and conferred a 2.2-fold increased risk of developing metastatic disease and a 2.1-fold increased risk of breast cancer-related death. ApoD positivity was not associated with AR or ERα nuclear positivity. However, patients with (≥1%) ERα-positive cancers with low (<20.7%) ApoD positivity, or those showing high (≥78%) AR positivity and low (<20.7%) ApoD positivity had better OS than other patient groups. CONCLUSIONS: ApoD expression could be used to predict breast cancer prognosis independently of ERα and AR expression.

The biological role and regulation of versican levels in cancer.

Increased expression of the proteoglycan, versican is strongly associated with poor outcome for many different cancers. Depending on the cancer type, versican is expressed by either the cancer cells themselves or by stromal cells surrounding the tumor. Versican plays diverse roles in cell adhesion, proliferation, migration and angiogenesis, all features of invasion and metastasis. These wide ranging functions have been attributed to the central glycosaminoglycan-binding region of versican, and to the N-(G1) and C-(G3) terminal globular domains which collectively interact with a large number of extracellular matrix and cell surface structural components. Here we review the recently identified mechanisms responsible for the regulation of versican expression and the biological roles that versican plays in cancer invasion and metastasis. The regulation of versican expression may represent one mechanism whereby cancer cells alter their surrounding microenvironment to facilitate the malignant growth and invasion of several tumor types. A greater understanding of the regulation of versican expression may contribute to the development of therapeutic methods to inhibit versican function and tumor invasion.

Prostatic chondroitin sulfate is increased in patients with metastatic disease but does not predict survival outcome.

BACKGROUND: Previous studies from our laboratory demonstrated a strong association between an elevated level of chondroitin sulfate (CS) in peritumoral stroma and PSA-relapse in patients with early stage disease. In this study we determined whether CS levels could predict overall survival in men diagnosed with advanced prostate cancer subsequently treated by orchiectomy alone. METHODS: CS was localized in archived prostatic tissues by immunohistochemistry, and the level of CS expression as measured by video image analysis was compared in cohorts of 157 and 60 men with early stage or advanced disease, respectively. RESULTS: The CS levels in the peritumoral stroma of patients without relapse after treatment for early stage disease was significantly reduced compared to levels in prostate tissue from patients who either relapsed (P = 0.003) or were diagnosed with advanced prostate cancer (P < 0.00001). There was no difference between the median CS level in the peritumoral prostatic stroma of early stage patients that relapsed after treatment and patients diagnosed with advanced prostate cancer. Increased CS levels (P < 0.0001) and high Gleason score (P < 0.0001) were associated with an increased rate of PSA-relapse in the cohort of patients with early stage disease. However, neither CS level nor Gleason score alone or in combination could predict survival outcome in patients with advanced prostate cancer following androgen deprivation therapy. CONCLUSIONS: Although peritumoral CS levels and Gleason score are strong predictors of relapse-free survival in early stage prostate cancer patients, neither peritumoral CS levels nor Gleason score can predict survival outcome in patients with advanced disease.

Immunohistochemical level of unsulfated chondroitin disaccharides in the cancer stroma is an independent predictor of prostate cancer relapse.

The glycosaminoglycan chondroitin sulfate is significantly increased in the peritumoral stroma of prostate tumors compared with normal stroma and is an independent predictor of prostate-specific antigen (PSA) relapse following radical prostatectomy. In this study, we determined whether specific alterations in the sulfation pattern of glycosaminoglycan chains in clinically organ-confined prostate cancer are associated with PSA relapse. Immunoreactivity to distinct glycosaminoglycan disaccharide epitopes was assessed by manually scoring the staining intensity in prostate tissues from patients with benign prostatic hyperplasia (n = 19), early-stage cancer (cohort 1, n = 55 and cohort 2, n = 275), and advanced-stage cancer (n = 20). Alterations to glycosaminoglycans in benign and malignant prostate tissues were determined by cellulose acetate chromatography and high-pressure liquid chromatography. Glycosaminoglycan disaccharide epitopes were localized to the peritumoral stroma of clinically localized prostate cancer. The level of immunostaining for unsulfated disaccharides (C0S) in the peritumoral stroma, but not for 4-sulfated (C4S) or 6-sulfated disaccharides (C6S), was significantly associated with the rate of PSA relapse following radical prostatectomy. High levels of C0S immunostaining were determined to be an independent predictor of PSA relapse (1.6-fold, P = 0.020). Advanced-stage prostate cancer tissues exhibited reduced electrophoretic mobility for chondroitin sulfate and increased unsulfated disaccharides when compared with benign prostatic hyperplasia tissues, whereas the sulfated disaccharide levels were unaffected. The level of C0S immunostaining in the peritumoral stroma is an independent determinant of PSA failure in clinically localized prostate cancer. Specific alterations to chondroitin sulfate side chains occurring during tumor development may be a crucial step for disease progression in prostate cancer.

The Magnitude of Androgen Receptor Positivity in Breast Cancer Is Critical for Reliable Prediction of Disease Outcome.

Purpose: Consensus is lacking regarding the androgen receptor (AR) as a prognostic marker in breast cancer. The objectives of this study were to comprehensively review the literature on AR prognostication and determine optimal criteria for AR as an independent predictor of breast cancer survival.Experimental Design: AR positivity was assessed by immunostaining in two clinically validated primary breast cancer cohorts [training cohort, n = 219; validation cohort, n = 418; 77% and 79% estrogen receptor alpha (ERα) positive, respectively]. The optimal AR cut-point was determined by ROC analysis in the training cohort and applied to both cohorts.Results: AR was an independent prognostic marker of breast cancer outcome in 22 of 46 (48%) previous studies that performed multivariate analyses. Most studies used cut-points of 1% or 10% nuclear positivity. Herein, neither 1% nor 10% cut-points were robustly prognostic. ROC analysis revealed that a higher AR cut-point (78% positivity) provided optimal sensitivity and specificity to predict breast cancer survival in the training (HR, 0.41; P = 0.015) and validation (HR, 0.50; P = 0.014) cohorts. Tenfold cross-validation confirmed the robustness of this AR cut-point. Patients with ERα-positive tumors and AR positivity ≥78% had the best survival in both cohorts (P < 0.0001). Among the combined ERα-positive cases, those with comparable or higher levels of AR (AR:ERα-positivity ratio >0.87) had the best outcomes (P < 0.0001).Conclusions: This study defines an optimal AR cut-point to reliably predict breast cancer survival. Testing this cut-point in prospective cohorts is warranted for implementation of AR as a prognostic factor in the clinical management of breast cancer. Clin Cancer Res; 24(10); 2328-41. ©2018 AACR.

Modulation of prostate cancer cell attachment to matrix by versican.

In this study, we examined whether versican, a recognized anti-cell adhesive molecule for various mesenchymal and nerve cell types, influences prostate cancer cell adhesion to extracellular matrix components. Prostate cancer cell adhesion to fibronectin, a major component of the stromal extracellular matrix was inhibited by versican-rich conditioned medium (CM) from cultured human prostatic fibroblasts. In contrast, cancer cell attachment to laminin, a component of basement membranes, was not affected by the same CM. Consistent with versican being the active inhibitory factor in the CM, the integrity of chondroitin sulfate side chains and an ability to bind the RGD (Arg-Gly-Asp) peptide sequence of fibronectin were essential for the inhibition of prostate cancer cell attachment to fibronectin. Subsequent studies with versican purified from human prostate fibroblast CM confirmed its anti-adhesive activity. We conclude that versican is an important modulator of tumor cell attachment to the interstitial stromal matrix of the prostate, the latter being an essential step in cancer cell motility and local invasion of the prostatic stroma.

Regulation of stromal versican expression by breast cancer cells and importance to relapse-free survival in patients with node-negative primary breast cancer.

PURPOSE: Determination of meaningful prognostic indicesremains a high priority for women diagnosed with node-negative primary breast cancer. Currently, 30% of these women relapse, and there is no reliable means of predicting this group of patients. This study investigates whether the level of expression of versican, an anticell adhesive proteoglycan, in the peritumoral stromal tissue of women with node-negative, primary breast cancer predicts relapse-free survival. This study also examines whether breast cancer cells regulate the secretion of versican by mammary fibroblasts. EXPERIMENTAL DESIGN: Immunoreactive versican was measured in breast cancer tissue sections of 58 node-negative patients by video image analysis. Primary isolates of mammary fibroblasts were cultured in medium conditioned by the breast cancer cell lines ZR-75-1, MCF-7, BT-20, and MB231. Changes in versican secretion were measured by immunoblotting and enhanced chemiluminescence. RESULTS: Cox analyses indicated that peritumoral versican level was the sole predictor of relapse-free survival. The relapse rate in patients with low versican levels was lower than in patients with high versican levels (Kaplan-Meier: 83% relapse free at 5 years for versican mean integrated absorbance <14 versus 33% for > or = 14, P = 0.0006). Accumulation of versican in medium of mammary fibroblasts was increased after culture in conditioned medium from breast cancer cell lines. CONCLUSIONS: Relapse in women with node-negative breast cancer is related to the level of versican deposited in peritumoral stroma by mammary fibroblasts. Versican secretion appears to be regulated by breast cancer cell mediators. Neoplastic remodeling of extracellular matrix through increased versican deposition may facilitate local invasion and metastasis.

Changes in steroid receptors and proteoglycan expression in the guinea pig prostate stroma during puberty and hormone manipulation.

BACKGROUND: Proteoglycans are structural and informational molecules important during embryogenesis and organ maturation. Maturation of the prostate is influenced by androgens and estrogens, but changes in the relative spatiotemporal expression of steroid receptors and proteoglycans during hormonal change are unexplored. METHODS: Guinea pig prostate was used to define hormone-induced changes in the expression of androgen (AR) and estrogen (ER(alpha)) receptors, chondroitin sulfate (CS) glycosaminoglycan and core proteins of versican and syndecan-1. Tissue locations of AR, ER(alpha), CS and the proteoglycans versican and syndecan-1 were determined by immunohistochemistry. Cellular content of ER(alpha) and syndecan-1 was assessed visually. Versican, CS56 epitope, and AR were quantified by image analysis. RESULTS: AR expression within prostate epithelial and stromal cell nuclei decreased following castration and increased following treatment of castrate animals with dihydrotestosterone (DHT). ER(alpha) expression was restricted to prostate stromal cell nuclei and decreased during puberty, and following treatment of castrate animals with DHT. Versican was present in periacinar stroma immediately peripheral to basal epithelial cells, fibromuscular stromal tissue bands surrounding acinar units, and loose fibrovascular connective tissue interspersed between individual acini. Versican and native CS expression decreased (>10-fold) in periacinar stroma during puberty and following administration of DHT to castrated animals. Expression of syndecan-1 was restricted to fibromuscular cells of prostate stroma, and remained constant during puberty and hormone manipulation. CONCLUSIONS: ER(alpha), versican core protein and CS side chain epitopes are negatively regulated in prostate stromal tissue by DHT, whilst AR levels are positively regulated.

Suppression of oncogenic NRAS by RNA interference induces apoptosis of human melanoma cells.

The majority of human melanomas harbor activating mutations in either the BRAF or NRAS gene. To date, the role of oncogenic NRAS in melanoma remains poorly defined and no current therapies are directed at specifically suppressing oncogenic NRAS in human melanoma tumors. The aim of our study, therefore, was to investigate the effects of suppressing oncogenic NRAS in human melanoma cell lines in vitro. Using both small interfering RNA- and plasmid based-RNA interference techniques, oncogenic NRAS was specifically suppressed in 2 human melanoma cell lines, 224 and BL, which harbor a codon 61 CAA (glutamine) to CGA (arginine) NRAS mutation. Suppression of oncogenic NRAS in these cell lines resulted in increased apoptosis. Furthermore, in 224 cells we demonstrated decreased phosphorylation of extracellular signal-regulated kinase (ERK) and Akt, and reduced expression of NF-kappaB and cyclin D1 in the N-Ras signaling pathway. In contrast, RNA interference directed at wild-type (WT) NRAS had no significant effect on apoptosis of 224 cells or 2 human melanoma cell lines (A375 and 397) containing WT NRAS but a codon 600 GTG (valine) to GAG (glutamate) mutation in BRAF. These data suggest that oncogenic NRAS is important for avoidance of apoptosis in melanomas that harbor the codon 61 NRAS mutation and emphasizes oncogenic NRAS as a therapeutic target in patients with tumors that harbor this mutation.