Publications by authors named "Kathryn R Lawson"

Oral and oropharyngeal cancer together constitute the sixth most common cancer worldwide, with over 400,000 new cases diagnosed each year. Early detection is paramount, as the 5-year survival rate for these cancers decreases markedly once tumors have become regionally invasive. In many tissues, including oral epithelia, neoplastic progression is accompanied by alterations in expression of the epithelial cell adhesion molecules E-cadherin and P-cadherin.

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Oral squamous carcinoma is the sixth most common cancer worldwide, and one of the most common cancers in developing countries. Regional and distant metastases comprise the majority of cases at initial diagnosis and correlate with poor patient outcomes. Oral epithelia is one of many tissue types to exhibit a cadherin switch during tumor progression, in which endogenous cell adhesion proteins, such as E-cadherin, give way to those of mesenchymal origin.

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Proteolytic digestion by trypsin and chymotrypsin was used to probe conformation and domain structure of the mu- and m-calpain molecules in the presence and the absence of Ca(2+). Both calpains have a compact structure in the absence of Ca(2+); incubation with either protease for 120 min results in only three or four major fragments. A 24-kDa fragment was produced by removal of the Gly-rich area in domain V of the 28-kDa subunit.

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Purpose: Analogues of the naturally occurring polyamines, alkylated on both terminal amines, are being developed as anticancer drugs. Because bisalkylated derivatives of putrescine (1,4-diaminobutane) are potent inhibitors of the flavin adenine dinucleotide-dependent polyamine oxidase (PAO), we asked whether PAO could detoxify synthetic bisalkylated polyamines with chain lengths longer than putrescine.

Experimental Design: We investigated the effects of one polyamine analogue in Chinese hamster ovary (CHO) and HCT116 human colon tumor-derived cells, which express dramatically different levels of PAO activity, and in these same cells treated with an inhibitor of PAO.

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