Plasma osteopontin levels are predictive of disease stage in patients with transitional cell carcinoma of the bladder

Hypoxia and its Modification in Bladder Cancer: Current and Future Perspectives

Radiotherapy plays an essential role in the curative treatment of muscle-invasive bladder cancer (MIBC). Hypoxia affects the response to MIBC radiotherapy, limiting radiocurability. Likewise, hypoxia influences MIBC genetic instability and malignant progression being associated with metastatic disease and a worse prognosis. Hypoxia identification in MIBC enables treatment stratification and the promise of improved survival. The most promising methods are histopathological markers such as necrosis; biomarkers of protein expression such as HIF-1α, GLUT-1 and CAIX; microRNAs; and novel mRNA signatures. Although hypoxia modification can take different forms, the gold standard remains carbogen and nicotinamide, which improve local control rates in bladder preservation and absolute overall survival with no significant increase in late toxicity. This is an exciting time for evolving therapies such as bioreductive agents, novel oxygen delivery techniques, immunotherapy and poly (ADP-ribose) polymerase 1 (PARP) inhibitors, all in development and representing upcoming trends in MIBC hypoxia modification. Whatever the future holds for hypoxia-modified radiotherapy, there is no doubt of its importance in MIBC. mRNA signatures provide an ideal platform for the selection of those with hypoxic tumours but are yet to qualified and integrated into the clinic. Future interventional trials will require biomarker stratification to ensure optimal treatment response to improve outcomes for patients with MIBC.

Risk Factors and Biomarkers for Chronic Hepatitis B Associated Hepatocellular Carcinoma

Globally, hepatitis B virus (HBV) related hepatocellular carcinoma (HCC) is one of the major causes of cancer-related mortality. This is, in part, due to delayed diagnosis and limited therapeutic options with more advanced stages of the disease. Given the prognostic importance of early diagnosis, novel methods for early detection are in need. Unlike most other cancer types, tissue is not required to diagnose HCC and is frequently avoided given the inherent risks of liver biopsy, so less invasive methods of obtaining tumor material are currently under investigation. Material shed from tumors into the periphery are being investigated for their potential to both surveil and diagnose patients for HCC. These materials include circulating tumor cells, DNA, RNA, and exosomes, and are collectively termed a “liquid biopsy”. In this review article, we discuss the evolving literature regarding the different risk factors for HCC and the types of emerging novel biomarkers that show promise in the prevention and early diagnosis of HCC within the context of HBV infection.

Clinical and in vitro analysis of Osteopontin as a prognostic indicator and unveil its potential downstream targets in bladder cancer

Osteopontin (OPN) plays an important role in cancer progression, however its prognostic significance and its downstream factors are largely elusive. In this study, we have shown that expression of OPN was significantly higher in bladder cancer specimens with higher T-stage or tumor grades. In addition, a high level of OPN was significantly associated with poorer survival in two independent bladder cancer patient cohorts totaling 389 bladder cancer patients with available survival data. We further identified Matrix metallopeptidase 9 (MMP9) and S100 calcium-binding protein A8 (S100A8) were both downstream factors for OPN in bladder cancer specimens and bladder cancer cell lines. Expression of OPN was significantly positively associated with that of MMP9 and S100A8, while overexpression of OPN resulted in upregulation of MMP9 and S100A8, and knockdown of OPN showed consistent downregulation of MMP9 and S100A8 expression levels. Importantly, expression levels of both MMP9 and S100A8 were significantly associated with higher T-stage, higher tumor grade and a shorter survival time in the bladder cancer patients. Interestingly, OPN expression only predicted survival in MMP9-high, but not MMP9-low subgroups, and in S100A8-low but not S100A8-high subgroups. Our results suggest that OPN, MMP9 and S100A8 all play a significant role in bladder cancer progression and are potential prognostic markers and therapeutic targets in bladder cancer. The mechanistic link between these three genes and bladder cancer progression warrants further investigation.

Gene expression profiling in bladder cancer identifies potential therapeutic targets

Despite advances in management, bladder cancer remains a major cause of cancer related complications. Characterisation of gene expression patterns in bladder cancer allows the identification of pathways involved in its pathogenesis, and may stimulate the development of novel therapies targeting these pathways. Between 2004 and 2005, cystoscopic bladder biopsies were obtained from 19 patients and 11 controls. These were subjected to whole transcript-based microarray analysis. Unsupervised hierarchical clustering was used to identify samples with similar expression profiles. Hypergeometric analysis was used to identify canonical pathways and curated networks having statistically significant enrichment of differentially expressed genes. Osteopontin (OPN) expression was validated by immunohistochemistry. Hierarchical clustering defined signatures, which differentiated between cancer and healthy tissue, muscle-invasive or non-muscle invasive cancer and healthy tissue, grade 1 and grade 3. Pathways associated with cell cycle and proliferation were markedly upregulated in muscle-invasive and grade 3 cancers. Genes associated with the classical complement pathway were downregulated in non-muscle invasive cancer. Osteopontin was markedly overexpressed in invasive cancer compared to healthy tissue. The present study contributes to a growing body of work on gene expression signatures in bladder cancer. The data support an important role for osteopontin in bladder cancer, and identify several pathways worthy of further investigation.

An Osteopontin/CD44 Axis in RhoGDI2-Mediated Metastasis Suppression

RhoGDI2 specifically suppresses bladder cancer metastasis but not primary tumor growth, which involves tumor-associated macrophages. We report that macrophage-secreted osteopontin binds to CD44s on the tumor cells and promotes invasion and clonal growth. These effects are RhoGDI2-sensitive and require CD44s binding to the Rac GEF TIAM1. Osteopontin expression correlates with tumor aggressiveness and poor clinical outcome in patients. Inhibiting this pathway potently blocked lung and lymph node metastasis; however, primary tumors and established metastasis were less sensitive. Osteopontin-CD44s-TIAM1 promotes clonal growth in vitro but not at high cell density. These data identify osteopontin-CD44-TIAM1-Rac1 axis as a RhoGDI2-sensitive pathway and potential therapeutic target in bladder cancer metastasis. They also elucidate the mechanism behind RhoGDI2 specificity for metastasis over established tumors.

Role of the host stroma in cancer and its therapeutic significance

Current cancer research focuses mainly upon the cancer cells in malignant tumours and is providing a growing database about aberrations in their genetic composition. However, tumours also contain non-cancerous host tissue, referred to as the stroma, which plays an active and indispensable role in tumour growth and influences the virulence of the neoplasm towards the host. Many cell types inhabit the stroma, amidst apparently inert fibrous and viscous matrix material, composed of complex polysaccharides, proteins and other molecules. Actually, all of these elements are in constant turnover, causing unpredictable evolution in the properties of the community. This article provides pathologic observations and data on reciprocal interactions between these stromal and neoplastic components of tumours and how they change during the course of the disease. Malignant progression depends upon dauntingly intricate communications between different specialised lineages within the cellular society, which enable rapid adaptation to changing circumstances. Opportunistic misuse of such communication networks enables tumour cells to recruit and incorporate adjacent normal stroma into their midst, so that they may grow, infiltrate and parasitise the host. The absolute dependency of primary tumours and metastases on their diverse stromal components for survival and their insatiable need to continuously recruit more stroma to support expansion, renders them vulnerable to strategies capable of disrupting the cellular interactions involved. This dependency is of critical importance for cancer therapy research, and proposed methods for turning this parasitic behaviour of tumours against themselves are suggested below.

Bone turnover markers in serum and urine as diagnostic, prognostic and monitoring biomarkers of bone metastasis

Bone metastases are characterized by increased osteoblastic and/or osteolytic processes depending on the tumor type. The altogether destructive effect of metastasis formation promoted by increased metabolic activity raises the release of components from the osseous metabolism into the blood stream. These components are either enzymes directly involved in the alteration processes, metabolites/proteins that develop during this or bone matrix proteins released during this. These biomarkers are categorized in relation to their involvement in the bone formation or resorption as bone formation and resorption markers. Based on a PubMed literature search, a critical appraisal of the various biomarkers for diagnostic, prognostic, and monitoring purposes is given for patients with skeletal metastases caused by breast, prostate, lung, or renal cell carcinomas.

Biochemical markers of bone turnover and clinical outcome in patients with renal cell and bladder carcinoma with bone metastases following treatment with zoledronic acid: The TUGAMO study

Background:

Levels of bone turnover markers (BTM) might be correlated with outcome in terms of skeletal-related events (SRE), disease progression, and death in patients with bladder cancer (BC) and renal cell carcinoma (RCC) with bone metastases (BM). We try to evaluate this possible correlation in patients who receive treatment with zoledronic acid (ZOL).

Methods:

This observational, prospective, and multicenter study analysed BTM and clinical outcome in these patients. Serum levels of bone alkaline phosphatase (BALP), procollagen type I amino-terminal propeptide (PINP), and beta-isomer of carboxy-terminal telopeptide of type I collagen (β-CTX) were analysed.

Results:

Patients with RCC who died or progressed had higher baseline β-CTX levels and those who experienced SRE during follow-up showed high baseline BALP levels. In BC, a poor rate of survival was related with high baseline β-CTX and BALP levels, and new SRE with increased PINP levels. Cox univariate analysis showed that β-CTX levels were associated with higher mortality and disease progression in RCC and higher mortality in BC. Bone alkaline phosphatase was associated with increased risk of premature SRE appearance in RCC and death in BC.

Conclusion:

Beta-isomer of carboxy-terminal telopeptide of type I collagen and BALP can be considered a complementary tool for prediction of clinical outcomes in patients with BC and RCC with BM treated with ZOL.

The value of plasma osteopontin levels as a predictive factor of disease stage and recurrence in patients with bladder urothelial carcinoma: a prospective study

This study was performed in order to determine the value of plasma osteopontin (OPN) levels as a predictive factor of disease stage and recurrence in patients with bladder urothelial carcinoma (UC). Data from 50 patients diagnosed to have bladder UC after transurethral resection of bladder tumor (TURBT) from 2009 to 2010 were evaluated prospectively. Blood tests were performed before and after TURBT, and plasma OPN levels were measured using enzyme-linked immunosorbent assay. Differences in OPN levels according to clinicopathologic variables were analyzed statistically. Significant differences in plasma OPN levels were observed between groups with and without muscle invasion (89.16 vs. 67.08 ng/mL, p=0.041). Comparison according to tumor grade found no significant difference between high and low grade groups (p=0.115). Mean plasma OPN levels decreased after TURBT without statistical significance (p=0.571). Between groups with recurrence and those without recurrence, OPN levels of the group with recurrence were higher without statistical significance (p=0.161). Comparison of plasma OPN levels according to performance of radical cystectomy (RC) showed significant differences; patients who underwent RC showed higher levels of plasma OPN (95.58 vs. 70.37 ng/mL, p=0.030). Comparison according to T stage after RC showed significant differences in OPN levels (T1: 67.45, T2: 86.60 and T3: 95.23 ng/mL, respectively, p=0.006). The group with lymph node invasion showed significantly higher levels of OPN, compared to the group without invasion (153.24 vs. 68.03 ng/mL, p=0.017). Preoperative plasma OPN levels correlated to muscle invasion of bladder UC and pathological stage after RC.

Role of the angiogenic components, VEGFA, FGF2, OPN and RHOC, in urothelial cell carcinoma of the urinary bladder

The objective of this study was to analyze the expression profile of the angiogenic components, vascular endothelial growth factor-A (VEGFA), basic fibroblast growth factor-2 (FGF2), osteopontin (OPN) and ras homolog gene family, member C (RHOC), in urothelial cell carcinoma (UCC) of the urinary bladder and to examine their role as candidate diagnostic biomarkers. Using qPCR, 77 samples of UCC of the urinary bladder and 77 matched tumor-associated normal samples were investigated to determine the expression of the four angiogenic components. The correlation between gene expression, patient survival and pathological features of the tumors was also examined. The VEGFA and OPN transcript levels were greater in the bladder cancer tissue than in the normal urothelium (P<0.001). Patients with higher VEGFA mRNA levels showed a tendency towards shorter cancer-specific survival. OPN levels showed a gradual increase, the lowest levels being found in non-invasive carcinoma and the highest in muscle invasive tumors. Elevated OPN levels indicated poor prognosis in connection with advanced disease stage (P<0.001). Both superficially invasive and muscle invasive tumors had significantly higher FGF2 levels compared to the control tissues (P=0.018 and P=0.050, respectively). Moreover, FGF2 was significantly higher in the metastatic vs. the non-metastatic tumors (P=0.0097). FGF2 levels exhibited a trend towards a correlation with worse patient survival. RHOC mRNA levels were higher in muscle invasive compared to superficially invasive tumors, as well as in grade III vs. grade I/II tumors. Furthermore, we detected worse overall survival for patients with high RHOC expression levels. VEGFA and FGF2 exhibited the best linear combination in the ROC curves for specificity and sensitivity. Thus, VEGFA and FGF2 may serve as candidate biomarkers for diagnostic purposes. Higher OPN expression may be used as a potential biomarker to predict patient survival relative to advanced tumor stage. However, further studies are required to investigate its role in urinary bladder carcinogenesis.

Osteopontin: an effector and an effect of tumor metastasis

Osteopontin (OPN) is a matricellular protein that is produced by multiple tissues in our body and is most abundant in bone. It is also produced by cancer cells and plays a determinative role in the growth, progression and metastasis of cancer. Clinically, OPN has been reported to be upregulated in tumor cells per se; this is also reflected by increased levels of OPN in the circulation. Thus, increased OPN levels the plasma are an effect of tumor growth and progression. Functionally, high OPN levels are determinative of higher incidence of bone metastases in mouse models and are clinically correlated with metastatic bone disease and bone resorption in advanced breast cancer patients. Several research efforts have been made to therapeutically target and inhibit the activities of OPN. In this article we have reviewed OPN in its role as an effector of critical steps in tumor progression and metastasis, with a particular emphasis on its role in facilitating bone metastasis of breast cancer. We have also addressed the role of the host-derived OPN in influencing the malignant behavior of the tumor cells.

Small integrin-binding ligand N-linked glycoproteins (SIBLINGs): multifunctional proteins in cancer

Numerous components and pathways are involved in the complex interplay between cancer cells and their environment. The family of glycophosphoproteins comprising osteopontin, bone sialoprotein, dentin matrix protein 1, dentin sialophosphoprotein and matrix extracellular phosphoglycoprotein - small integrin-binding ligand N-linked glycoproteins (SIBLINGs) - are emerging as important players in many stages of cancer progression. From their detection in various human cancers to the demonstration of their key functional roles during malignant transformation, invasion and metastasis, the SIBLINGs are proteins with potential as diagnostic and prognostic tools, as well as new therapeutic targets.

Osteopontin gene expression determines spontaneous metastatic performance of orthotopic human breast cancer xenografts

A major problem in the therapeutic management of cancer is the growth of metastases in distant organs, but the genes orchestrating the process need to be identified for the rational design of new treatment. Here, we provide decisive experimental evidence demonstrating the causal involvement of a specific gene, osteopontin (OPN), in the pathogenesis of metastasis by human breast cancer cells and implicating some of its probable partners. Stable long-term depletion, or up-regulation, of OPN gene expression in a matched, isogenic pair of human breast cancer cell lines of differing metastatic proficiency reproducibly changed their ability to colonize distant organs. OPN down-regulation was achieved by transduction of the metastatic line with a DNA construct encoding a small hairpin RNA in a vector labeled with red fluorescent protein and resulted in a marked reduction of metastatic load (P < 0.01). Up-regulation of OPN in the negligibly metastatic line, with a green fluorescent protein-marked retroviral vector containing OPN cDNA driven by a strong promoter, resulted in heavy colonization of the lungs and lymph nodes (P < 0.005). The reciprocal changes in behavior of these matched cell lines cross-corroborate each other. Concomitant changes were seen in the expression of other metastasis-related genes in both modulated lines. The data indicate that therapeutic targeting of tumor OPN molecules could reset metastatically relevant gene networks, resulting in clinical benefit.

Elevated plasma osteopontin as marker for distant metastases and poor survival in patients with renal cell carcinoma

PURPOSE

To evaluate diagnostic and prognostic significance of plasma osteopontin (OPN) in patients with renal cell carcinoma (RCC).

METHODS

The retrospective study included 80 patients with RCC (pN0M0, n = 32; pN1M0, n = 11; M1, and n = 37), and 52 healthy controls (27 females and 25 males). OPN, the bone marker bone-specific alkaline phosphatase (bALP) and carboxyterminal telopetide of type-I collagen (ICTP), and the enzymes alanine aminotransferase (ALAT), and gamma-glutamyltransferase (GGT) were evaluated together with Memorial Sloan-Kettering Cancer Center (MSKCC) laboratory parameters. Data were analyzed by receiver-operating characteristics (ROC), survival analysis, and Cox proportional hazards regression model.

RESULTS

OPN and ICTP levels in RCC patients with distant metastases were significantly elevated (medians 115 and 4.7 microg/l, P < 0.001) compared to those without metastases (31.1 and 2.5 microg/l) and controls (28.9 and 2.1 microg/l) but did not differ between patients with bone or non-bone metastases. Both bALP and ALAT were not different between all study groups, while GGT was only increased in patients with non-bone metastases. In ROC analysis, OPN showed the best discrimination between patients with and without metastases (area under the curve: 0.888). High OPN values were associated with poor survival (Kaplan-Meier analysis, log-rank test, P = 0.002). Multivariate Cox regression with forward and backward stepwise elimination confirmed plasma OPN as independent predictive survival factor in RCC patients.

CONCLUSIONS

Our results show that high plasma OPN levels are associated with distant metastases and poor survival in RCC patients. The use of OPN as potential marker to monitor new treatment strategies in patients with advanced RCC should be evaluated in prospective studies.

Serial Plasma Osteopontin Levels Have Prognostic Value in Metastatic Breast Cancer

PURPOSE

Osteopontin is a malignancy-associated protein measurable in blood and tumor tissue. To evaluate its prognostic value in advanced disease, we conducted a prospective clinical study measuring serial osteopontin plasma levels in women with metastatic breast cancer throughout the course of their disease.

EXPERIMENTAL DESIGN

One hundred fifty-eight women with newly diagnosed metastatic breast cancer were enrolled in the study. Plasma osteopontin was measured using our validated ELISA, at baseline and every 3 to 12 weeks during and after therapy until death. Multivariate time-dependent survival analyses were conducted using models that right censored patient outcomes 3, 6, and 12 months after the last known osteopontin measurement.

RESULTS

Osteopontin was measured in 1,378 samples (median, 9 per patient). Ninety-nine patients had elevated baseline osteopontin (median, 177 ng/mL; range, 1-2,648 ng/mL). In univariate analysis, elevated baseline osteopontin was associated with short survival (P = 0.02). In a multivariate model incorporating standard prognostic factors, baseline osteopontin was significantly associated with survival duration (relative risk, 1.001; P = 0.038). Metastasis-free interval, visceral metastases, and Eastern Cooperative Oncology Group status 2 to 4 also retained significance. In a multivariate model incorporating standard prognostic factors and changes in sequential osteopontin levels, an osteopontin increase of >250 ng/mL at any time was the variable with the most prognostic value for poor survival (relative risk, 3.26; P = 0.0003), and poor Eastern Cooperative Oncology Group status also retained significance.

CONCLUSIONS

This is the first study to show that in women with metastatic breast cancer, increases in osteopontin levels over time are strongly associated with poor survival. Sequential monitoring of osteopontin may have use in making treatment decisions for these patients.