Collagen subunit proteins COL1A1, COL1A2, COL3A1, and COL11A1 have been related to triple-negative breast cancer: COL1A1 expression is elevated in TNBC tissues and is associated with increased tumor stiffness, promoting cancer progression and metastasis, making it an independent prognostic factor [122]. This evidence concerns the gene COL3A1 and neoplasm.