Low detection rate of p53 antibodies in sera of soft tissue sarcoma patients

Elevated tumor and serum levels of the hypoxia-associated protein osteopontin are associated with prognosis for soft tissue sarcoma patients

BACKGROUND

Osteopontin (OPN) overexpression is correlated with a poor prognosis for tumor patients. However, only a few studies investigated the prognostic impact of expression of OPN in soft tissue sarcomas (STS) yet.

METHODS

This study is based on tumor and serum samples from 93 adult STS patients. We investigated OPN protein levels in serum (n = 86) and tumor tissue (n = 80) by ELISA and OPN mRNA levels in tumor tissue (n = 68) by quantitative real-time PCR.

RESULTS

No correlation was found between OPN levels in serum and tumor tissue. Moreover, an elevated OPN protein level in the serum was significantly associated with clinical parameters such as higher stage (p = 0.004), higher grade (p = 0.003), subtype (p = 0.002) and larger tumor size (p = 0.03). OPN protein levels in the tumor tissue were associated with higher stage (p = 0.06), higher grade (p = 0.003), subtype (p = 0.07) and an increased rate of relapse (p = 0.02). In addition, using a Cox's proportional hazards regression model, we found that an elevated OPN protein level in the serum and tumor tissue extracts is a significant negative prognostic factor for patients with STS. The relative risks of tumor-related death were 2.2 (p < 0.05) and 3.7 (p = 0.01), respectively.

CONCLUSION

Our data suggest OPN protein in serum as well as in tumor tissue extracts is an important prognostic factor for soft tissue sarcoma patients.

Clinical evaluation of serum p53 antibodies in patients with upper urinary tract tumors

PURPOSE

We retrospectively assessed the clinical significance of anti-p53 antibody (S-p53Ab) status in the serum of patients with upper urinary tract tumors.

MATERIALS AND METHODS

Enzyme-linked immunosorbent assay was used to analyze S-p53Abs in 63 upper urinary tract tumors. Its incidence and clinical or pathological background were analyzed in comparison with 80 bladder tumors.

RESULTS

The prevalence of S-p53Abs in patients with upper urinary tract tumors was higher than that in patients with bladder tumors (27.0% vs 17.5%). Especially, 34.8% of patients showed positive S-p53Abs in invasive upper urinary tract tumors (pT1 or more). In upper urinary tract tumors the prevalence of S-p53Abs significantly correlated with higher grade (p <0.01), higher stage (p = 0.02), positive lymph nodes (p = 0.03) and p53 nuclear accumulation (p <0.01). However, disease specific survival after nephroureterectomy did not differ between patients with negative and positive S-p53Abs.

CONCLUSIONS

Our data suggest the possibility of the clinical application of S-p53Abs, especially for the detection of high grade or high stage tumors in the upper urinary tract. However, the usefulness of S-p53Abs as prognostic marker seems to be extremely limited in patients with urothelial tumors.