Elevated circulating levels of osteopontin are associated with metastasis in advanced non-small cell lung cancer

Baseline serum levels of osteopontin predict clinical response to treatment with nivolumab in patients with non-small cell lung cancer

Treatment with nivolumab improves survival and response rate in non-small cell lung cancer (NSCLC). Nevertheless, due to its high financial cost, identifying predictors of response to treatment has become an urgent need. Here, we focused on serum osteopontin (OPN), a pleiotropic protein overexpressed in lung cancer and involved in the immune response. A cohort of NSCLC patients (n = 72) treated with nivolumab was enrolled. Blood samples were collected at the time of first five nivolumab administrations. OPN and high-sensitivity C-reactive protein (hs-CRP) were assayed at each time point. The primary endpoint was to assess the predictive value of baseline serum levels of OPN towards overall survival (OS). Secondary endpoints included the potential association between OPN, hs-CRP and response to nivolumab. OPN and hs-CRP correlate with each other, with neutrophil count and biochemical markers of metastatic disease. At baseline, serum OPN increased with increasing Eastern Cooperative Oncology Group scale of Performance Status (ECOG PS). When Eastern Cooperative Oncology Group scale of Performance Status) (RECIST) criteria were considered, high baseline OPN levels were associated with a worse response to nivolumab. Cox hazard regression further confirmed baseline serum OPN as a predictor of mortality with the best predictive accuracy for serum levels above 37.7 ng/mL. Patients above the cut-off value had a higher mortality rate as compared to low serum OPN levels during follow up. Serum OPN may have a predictive role in NSCLC patients treated with nivolumab. Although larger confirmatory studies are needed, measuring serum OPN levels at baseline can be a clinically useful tool in a near future.

The cancer-related transcription factor RUNX2 modulates expression and secretion of the matricellular protein osteopontin in osteosarcoma cells to promote adhesion to endothelial pulmonary cells and lung metastasis

Osteosarcomas are bone tumors that frequently metastasize to the lung. Aberrant expression of the transcription factor, runt-related transcription factor 2 (RUNX2), is a key pathological feature in osteosarcoma and associated with loss of p53 and miR-34 expression. Elevated RUNX2 may transcriptionally activate genes mediating tumor progression and metastasis, including the RUNX2 target gene osteopontin (OPN/SPP1). This gene encodes a secreted matricellular protein produced by osteoblasts to regulate bone matrix remodeling and tissue calcification. Here we investigated whether and how the RUNX2/OPN axis regulates lung metastasis of osteosarcoma. Importantly, RUNX2 depletion attenuates lung metastasis of osteosarcoma cells in vivo. Using next-generation RNA-sequencing, protein-based assays, as well as the loss- and gain-of-function approaches in selected osteosarcoma cell lines, we show that osteopontin messenger RNA levels closely correlate with RUNX2 expression and that RUNX2 controls the levels of secreted osteopontin. Elevated osteopontin levels promote heterotypic cell-cell adhesion of osteosarcoma cells to human pulmonary microvascular endothelial cells, but not in the presence of neutralizing antibodies. Collectively, these findings indicate that the RUNX2/OPN axis regulates the ability of osteosarcoma cells to attach to pulmonary endothelial cells as a key step in metastasis of osteosarcoma cells to the lung.

The prognostic value of osteopontin expression in non-small cell lung cancer: a meta-analysis

To investigate the association of Osteopontin (OPN) expression in tumor tissue with clinicopathological features of non-small cell lung carcinoma (NSCLC) patients. Publications assessing the clinicopathological characteristics and prognostic significance of OPN in expression NSCLC were identified up to March 2014. A meta-analysis of eligible studies was performed using standard statistical methods to clarify the association between OPN expression and these clinical parameters. A total of eleven studies met the inclusion criteria, and included 1536 cases of NSCLC tumor tissue and 340 cases of normal lung tissue. The OPN expression rate in NSCLC tissue was higher than normal tissue [Odds ratio (OR) 6.427; 95% confidence interval (CI) 4.689-8.808; P = 0.000]. Simultaneously, we also found that OPN expression was positively associated with stage (OR 0.332; 95% CI 0.250-0.440; P = 0.000), lymph node metastasis (OR 3.094; 95% CI 2.295-4.172; P = 0.000), tumor size (tumor size <3 cm vs. ≥3 cm; OR 0.484; 95% CI 0.303-0.773; P = 0.002) and pathology (OR 0.611; 95% CI 0.466-0.800; P = 0.000). It was unrelated that OPN expression in NSCLC tissue with and degree of differentiation and other clinical features (P > 0.05). Experimental findings indicate that, OPN plays a crucial role in the development of NSCLC.

Osteopontin and Osteoprotegerin as Potential Biomarkers in Abdominal Aortic Aneurysm before and after Treatment

Aim. Although osteopontin (OPN) and osteoprotegerin (OPG) have been associated with abdominal aortic aneurysms (AAAs), no association of these two biomarkers with AAA surgical or endovascular treatment has been reported. Material and Methods. Seventy-four AAA patients were prospectively selected for open or endovascular repair. All aneurysms were classified (Types A–E) according to aneurysmal extent in CT imaging (EUROSTAR criteria). All patients had preoperative serum OPN and OPG values measurements and 1 week after the procedure. Preoperative and postoperative values were compared with a control group of twenty patients (inguinal hernia repair). Results. Preoperative OPN values in patients with any type of aneurysm were higher than in the control group, while OPG values showed no difference. Postoperative OPN values in AAA patients were higher than in the control group. OPN values increased after open surgery and after EVAR. OPG values increased after open surgery but not after EVAR. There was no difference in OPN/OPG values between EVAR and open surgery postoperatively. Conclusions. OPN values are associated with aneurysm presence but not with aneurysm extent. OPG values are not associated either with aneurysm presence or with aneurysm extent. OPN values increase after AAA repair, independently of the type of repair.