19q13.41

PRSS20,TLSP

Prostate cancer

A number of investigations have been reported concerning the role of KLK11 as a potential diagnostic biomarker for prostate cancer (CaP). Prostate specific antigen (PSA) is currently the most widely used diagnostic marker for CaP. However, measuring PSA alone is lack of specificity, since some benign prostatic diseases, such as benign prostatic hyperplasia (BPH) and prostatitis, can also have increased serum PSA levels, whereas some CaP patients may have only mild elevation of PSA (4-10 ng/mL). To improve the specificity, a number of additional analyses, such as measuring the molecular forms of PSA, have been proposed. Patients with low free to total PSA ratios are considered to have higher risk of developing CaP. In spite of these efforts, false positive and false negative still occur and doctors frequently need to rely on prostate biopsy to make the final diagnosis. Some investigations have shown that measuring serum KLK11 concentrations may help discriminate CaP from BPH and reduce the number of unnecessary biopsies. Similar to PSA, serum KLK11 concentrations are elevated in the majority of CaP patients. However, compared to the BPH patients, the CaP patients tend to have lower serum KLK11 concentrations and lower KLK11 to total PSA ratios. In those patients that have less than 20% free PSA, measuring KLK11 to total PSA ratio identified 54% to have BPH. As such, it seems that KLK11 to total PSA ratio might be a complementary marker for free PSA percentage and combination of these two markers results in better specificity for CaP. KLK11 might not be superior to PSA in population screening. In a retrospective study, serum KLK11 or KLK11 to PSA ratio showed no advantage over PSA alone to differentiate CaP patients from noncancer individuals whose total PSA levels are in the range of 2.5 to 10 ng/mL.

Tissue expression levels of KLK11 may be used as a prognostic indicator for prostate cancer. Lower KLK11 mRNA levels have been found to be associated with higher tumor grade, tumor stage, and Gleason score, suggesting that KLK11 might be able to indicate the aggressiveness of prostate tumors.

No cytogenetic abnormalities are identified so far.

Not identified so far.

Ovarian cancer

KLK11 has shown promise as a diagnostic biomarker for ovarian cancer. Earlier studies have revealed that serum KLK11 concentrations are elevated in the majority of ovarian cancer patients. Subsequent investigations further demonstrate that KLK11 is able to distinguish ovarian cancer cases from healthy controls. More importantly, it is less sensitive to benign ovarian diseases than is CA125, the most widely used diagnostic marker for ovarian cancer. Moreover, it has high temporal stability, which implies that it could be used in a longitudinal screening program for early detection.

Many investigations have clearly demonstrated that KLK11 has elevated protein levels in primary ovarian tumors than in normal tissue, benign or nonovarian metastatic tumors. In general, higher levels of KLK11 in ovarian tumor extracts are predictive of favorable outcome. They are more likely to be associated with early stage, responsive to chemotherapy, and longer progression free survival.

No cytogenetic abnormalities are identified so far.

Not identified so far.

Lung cancer

The prognostic role of KLK11 has also been explored in lung cancer both at the mRNA and protein levels. With quantitative PCR, it has shown that KLK11 mRNA levels are lower in tumor tissues in comparison with adjacent normal counterparts. No significant correlation is identified with clinical stages, tumor status, and lymph node status. However, those patients with low KLK11 mRNA expression seem to have a significantly worse prognosis than those with high levels. At the protein level, serum KLK11 concentrations in non-small cell lung cancer patients are higher than in healthy controls and they are positively correlated with tumor stages.

No cytogenetic abnormalities are identified so far.

Not identified so far.