TJP1 and neoplasm: However, ZO‐1 protein expression was observed to be prominent in the periphery of cellular clumps in AlgLung hydrogels suggesting a tighter epithelial barrier (Figure S11, Supporting Information).[29] Such complex, co‐expression of epithelial and mesenchymal markers is not atypical for clinical LUAD samples that was recapitulated in tumor‐mimetic hydrogels.[30] Moreover, sulfated hydrogels strongly induced the expression of several EMT‐regulating transcription factors such as ZEB1, ZEB2, and SNAIL (Figure 3b), further emphasizing the role of ECM sulfation (Figure 3c).