Abstract: An isolated nucleic acid encoding a C-terminal fragment of paraspeckle component 1 (PSPC1) is disclosed. The C-terminal fragment of the PSPC1 comprises an extension of more than 10 but no greater than 131 amino acid residues with its C-terminal amino acid identical to the C-terminus of the PSPC1 sequence SEQ ID NO: 3 and exhibits a biological activity against tumor cells. The tumor cells are associated with either PSPC1 or protein tyrosine kinase 6 (PTK6), or both. The anti-tumor activity is at least one selected from the group consisting of: (a) suppressing tumor cell growth; (b) suppressing tumor cell progression; (c) suppressing tumor cell metastasis; (d) decreasing PSPC1 expression; and (e) decreasing oncogenic PTK6 expression in cytoplasm. Also disclosed is a peptide comprising a C-terminal fragment sequence of PSPC1. A reagent kit and method for predicting tumor progression, metastasis, and prognosis in a cancer patient are also disclosed.

Abstract: An isolated nucleic acid encoding a C-terminal fragment of paraspeckle component 1 (PSPC1) is disclosed. The C-terminal fragment of the PSPC1 comprises an extension of more than 10 but no greater than 131 amino acid residues with its C-terminal amino acid identical to the C-terminus of the PSPC1 sequence SEQ ID NO: 3 and exhibits a biological activity against tumor cells. The tumor cells are associated with either PSPC1 or protein tyrosine kinase 6 (PTK6), or both. The anti-tumor activity is at least one selected from the group consisting of: (a) suppressing tumor cell growth; (b) suppressing tumor cell progression; (c) suppressing tumor cell metastasis; (d) decreasing PSPC1 expression; and (e) decreasing oncogenic PTK6 expression in cytoplasm. Also disclosed is a peptide comprising a C-terminal fragment sequence of PSPC1. A reagent kit and method for predicting tumor progression, metastasis, and prognosis in a cancer patient are also disclosed.