CTTN and carcinoma: Carcinoma cells can utilize protrusive invadopodia, sites of MMP exocytosis, to invade through the basement membrane and ECM-rich interstitial stroma.37, 38, 39 We observed that Lpd co-localized with the invadopodial marker cortactin at invadopodia, at sites of matrix degradation (Figure 5f).