Targeted proteomics of solid cancers: from quantification of known biomarkers towards reading the digital proteome maps

<p>The concept of personalized medicine includes novel protein biomarkers that are expected to improve the early detection, diagnosis and therapy monitoring of malignant diseases. Tissues, biofluids, cell lines and xenograft models are the common sources of biomarker candidates that require verification of clinical value in independent patient cohorts. Targeted proteomics – based on selected reaction monitoring, or data extraction from data-independent acquisition based digital maps – now represents a promising mass spectrometry alternative to immunochemical methods. To date, it has been successfully used in a high number of studies answering clinical questions on solid malignancies: breast, colorectal, prostate, ovarian, endometrial, pancreatic, hepatocellular, lung, bladder and others. It plays an important role in functional proteomic experiments that include studying the role of post-translational modifications in cancer progression. This review summarizes verified biomarker candidates successfully quantified by targeted proteomics in this field and directs the readers who plan to design their own hypothesis-driven experiments to appropriate sources of methods and knowledge.</p

Tamoxifen-Dependent Induction of <i>AGR2</i> Is Associated with Increased Aggressiveness of Endometrial Cancer Cells

<p>Tamoxifen treatment in breast cancer patients is associated with increased risk of endometrial malignancies. Significantly, higher <i>AGR2</i> expression was found in endometrial cancers that developed in women previously treated with tamoxifen compared to those who had not been exposed to tamoxifen. An association of elevated <i>AGR2</i> level with myometrial invasion occurrence and invasion depth was also found. <i>In vitro</i> analyses identified a stimulatory effect of <i>AGR2</i> on cellular proliferation. Although adverse tamoxifen effects on endometrial cells remain elusive, our work identifies elevated <i>AGR2</i> as a candidate tamoxifen-dependent mechanism of action responsible for increased incidence of endometrial cancer.</p