Molecular Cloning and Characterization of Plastin, a Human Leukocyte Protein Expressed in Transformed Human Fibroblasts

Abstract

The phosphoprotein plastin was originally identified as an abundant transformation-induced polypeptide of chemically transformed neoplastic human fibroblasts. This abundant protein is normally expressed only in leukocytes, suggesting that it may play a role in hemopoietic cell differentiation. Protein microsequencing of plastin purified from leukemic T lymphocytes by high-resolution two-dimensional gel electrophoresis produced eight internal oligopeptide sequences. An oligodeoxynucleotide probe corresponding to one of the oligopeptides was used to clone cDNAs from transformed human fibroblasts that encoded the seven other oligopeptides predicted for human plastin. Sequencing and characterization of two cloned cDNAs revealed the existence of two distinct, but closely related, isoforms of plastin--l-plastin, which is expressed in leukocytes and transformed fibroblasts, and t-plastin, which is expressed in normal cells of solid tissues and transformed fibroblasts. The leukocyte isoform l-plastin is expressed in a diverse variety of human tumor cell lines, suggesting that it may be involved in the neoplastic process of some solid human tumors.

LCP1 is a potential prognostic biomarker and correlates with immune infiltration in triple negative breast cancer

“…LCP1 was initially isolated from broblasts of tumor patients and subsequently detected in various cell lines and solid tumor samples [39,40]. Accumulating research has revealed that the upregulation of LCP1 expression is closely associated with the development of a wide range of human tumors, including colorectal cancer, prostate cancer, breast cancer, and oral cancer [20,21,[41][42][43].…”

LCP1 correlates with immune infiltration: a prognostic marker for triple-negative breast cancer

“…LCP1 was initially isolated from fibroblasts of tumor patients and subsequently detected in various cell lines and solid tumor samples [ 40 , 41 ]. Accumulating research has revealed that the upregulation of LCP1 expression is closely associated with the development of a wide range of human tumors, including colorectal cancer, prostate cancer, breast cancer, and oral cancer [ 20 , 21 , 42 – 44 ].…”

The intricate mechanism of PLS3 in bone homeostasis and disease

“…Plastin is an ancient and evolutionarily highly conserved family of actin-binding proteins that are expressed in a tissue-specific manner (1,11). Three plastin isoforms are expressed in vertebrates: PLS1 (I-plastin) is expressed in absorptive intestinal and kidney cells (12), PLS2 (LCP, LCP1, or L-plastin) is predominantly found in hematopoietic and cancer cells (1,13,14), while PLS3 (T-plastin) is ubiquitously expressed in all solid tissues (1,15). Interestingly, about 5% of the general population shows increased PLS3 expression in blood (16).…”