POSTN and breast cancer: In human medicine, studies on several cancer types, such as non-small cell lung cancer (NSCLC), renal cell carcinoma (RCC), malignant pleural mesothelioma (MPM), breast cancers (1, 14, 15), and others, have demonstrated that high POSTN levels are usually associated with a more aggressive tumor behavior, advance stage, and poor prognosis, suggesting that POSTN levels could be a useful prognostic biomarker (1, 9, 16–21).