In recent years, the interest of studying the role of impaired signalling for diseases15,16 has grown and a prime target is enzymes that are regulated with the help of kinases and dephosphorylation occurring only in bacteria vs. serine/threonine and tyrosine phosphorylation/dephosphorylation in vertebrate has been shown to be no longer correct.9 PHPT1, the first protein histidine phosphatase discovered in vertebrates,7,8 had been found its great roles in lung cancer migration and invasion in our previous in vitro studies.5,14 Based on the investigations in cell lines, we performed immunohistochemistry to analyze the protein expression of PHPT1 in lung cancer patients’ tissues and the relationship of its expression with clinicopathological features.
As reported in our previous studies, PHPT1 was differentially expressed in different metastasis potential of lung cancer cell lines,5 and silencing or overexpression of PHPT1 might affect the lung cancer cells migration and invasion.14 Those results suggested that the expression of PHPT1 might vary in different lung cancer patients’ tissues with different clinicopathological features. Interestingly, the results in this study supported the postulate and confirmed that PHPT1 was not only taking part in lung cancer cell migration and invasion but also could be a sign of lung cancer and its development.
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