TGFB1 and nasopharyngeal carcinoma: We observed that spheroids formed using certain NPC donors, which were more abundant in vimentin expression (NPC1), had high endogenous mRNA levels of TGFβ1 (Figure 3a), apparently providing the propensity for spontaneous fibrous tissue deposition, marked by progressively increasing COL1A1 and αSMA expression (Figure 3b).