BACKGROUND: Deficiency in butyrylcholinesterase (BChE), a condition commonly noticed in liver damage, inflammation, and malnutrition, has previously been associated with impaired prognosis in different malignancies. The aim of the present study was to investigate the value of pretreatment serum BChE levels as a prognostic biomarker in patients with cervical cancer treated with primary (chemotherapy-[chemo-])radiation therapy. METHODS: We retrospectively evaluated data of a consecutive series of patients with cervical cancer treated with primary (chemo-)radiation therapy between 1998 and 2015. Pretreatment serum BChE levels were correlated with clinico-pathological parameters and response to treatment. Uni- and multivariate survival analyses were performed to assess the association between decreased serum BChE levels and progression-free (PFS), cancer-specific (CSS), and overall survival (OS). RESULTS: A total of 356 patients were eligible for inclusion into the present study. The median (IQR) pretreatment serum BChE level was 6180 (4990-7710)IU/l. Lower serum BChE levels were associated with lower BMI (p< 0.001), advanced tumor stage (p= 0.04), poor treatment response (p= 0.002), the occurrence of disease recurrence (p= 0.003), and the risk of death (p< 0.001). In uni- and multivariate analyses, low pretreatment serum BChE levels were independently associated with shorter PFS (HR 1.8 [1.2-2.6]; p= 0.002), CSS (HR 2.2 [1.4-3.5], p< 0.001), and OS (HR 2.0 [1.4-2.9]; p< 0.001). CONCLUSIONS: Low pretreatment serum BChE levels are associated with advanced tumor stage and poor response to treatment, and serve as an independent prognostic biomarker for shorter PFS, CSS, and OS in patients with cervical cancer treated with primary (chemo-)radiation therapy.
        
Title: Characterisation of human dipeptidyl peptidase IV expressed in Pichia pastoris. A structural and mechanistic comparison between the recombinant human and the purified porcine enzyme Bar J, Weber A, Hoffmann T, Stork J, Wermann M, Wagner L, Aust S, Gerhartz B, Demuth HU Ref: Biol Chem, 384:1553, 2003 : PubMed
Dipeptidyl peptidase IV/CD26 (DP IV) is a multifunctional serine protease cleaving off dipeptides from the N-terminus of peptides. The enzyme is expressed on the surface of epithelial and endothelial cells as a type II transmembrane protein. However, a soluble form of DP IV is also present in body fluids. Large scale expression of soluble human recombinant His(6)-37-766 DP IV, using the methylotrophic yeast Pichia pastoris, yielded 1.7 mg DP IV protein per litre of fermentation supernatant. The characterisation of recombinant DP IV confirmed proper folding and glycosylation similar to DP IV purified from porcine kidney. Kinetic comparison of both proteins using short synthetic substrates and inhibitors revealed similar characteristics. However, interaction analysis of both proteins with the gastrointestinal hormone GLP-1(7-36) resulted in significantly different binding constants for the human and the porcine enzyme (Kd = 153.0 +/- 17.0 microM and Kd = 33.4 +/- 2.2 microM, respectively). In contrast, the enzyme adenosine deaminase binds stronger to human than to porcine DP IV (Kd = 2.15 +/- 0.18 nM and Kd = 7.38 +/- 0.54 nM, respectively). Even though the sequence of porcine DP IV, amplified by RT-PCR, revealed 88% identity between both enzymes, the species-specific variations between amino acids 328 to 341 are likely to be responsible for the differences in ADA-binding.