MALAT1 and breast cancer: To verify presence and quantify mRNA levels of these alternative splicing variants in our breast cancer series, we carried out non-quantitative (classical) RT–PCR using primer pairs with one of the two primers placed at the junction of the two spliced regions: U2/L2 for the 243-bp alternatively spliced MALAT1 transcript (Δ2sv-MALAT1) and U18/L18 for the 119-bp alternatively spliced MALAT1 transcript (Δ1sv-MALAT1; Figure 1).