Expression and characterization of bifunctional fusion proteins possessing antitumor and thrombolytic function for targeting therapy

Effective prediction model for preventing postoperative deep vein thrombosis during bladder cancer treatment

Objective

To begin to understand how to prevent deep vein thrombosis (DVT) after an innovative operation termed intracorporeal laparoscopic reconstruction of detenial sigmoid neobladder, we explored the factors that influence DVT following surgery, with the aim of constructing a model for predicting DVT occurrence.

Methods

This retrospective study included 151 bladder cancer patients who underwent intracorporeal laparoscopic reconstruction of detenial sigmoid neobladder. Data describing general clinical characteristics and other common parameters were collected and analyzed. Thereafter, we generated model evaluation curves and finally cross-validated their extrapolations.

Results

Age and body mass index were risk factors for DVT, whereas postoperative use of hemostatic agents and postoperative passive muscle massage were significant protective factors. Model evaluation curves showed that the model had high accuracy and little bias. Cross-validation affirmed the accuracy of our model.

Conclusion

The prediction model constructed herein was highly accurate and had little bias; thus, it can be used to predict the likelihood of developing DVT after surgery.

Production of a bioactive recombinant chicken matrix metalloproteinase-11 peptide in Escherichia coli

Matrix metalloproteinase-11 (MMP-11) is known to be highly expressed in metastatic and most invasive forms of tumors. Being selectively expressed in tumor tissues, MMP-11 is a promising target for immunotherapy against tumors. Here, we report the production of a thioredoxin-tagged bioactive recombinant chicken MMP-11 (cMMP-11) peptide excluding the secretory signal and propeptide in Escherichia coli T7 Express lysY using pET32b(+) vector. High-level expression and purification of the bioactive peptide were achieved by induction with 1.0 mM isopropyl-β-d-thiogalactopyranoside for 4 H at 37 °C followed by affinity chromatography under denaturing condition and slow dialysis. The recombinant peptide exhibited both caseinolytic and gelatinase activities without requiring activation by 4-aminophenylmercuric acetate. The antisera raised against the peptide in rabbits showed a strong reaction with the whole recombinant peptide as well as 37 kDa cMMP-11 mature peptide and cross-reactivity with a 43 kDa protein in murine breast tumor of 4T1 origin in Western blot analysis. The 43 kDa protein in the tumor homogenate showed immunoreactivity with a monoclonal antibody against human MMP-11, suggesting it to be murine MMP-11 having cross-reactivity with the antisera raised against cMMP-11 peptide. Altogether, the study characterized the production of a bioactive and immunogenic recombinant cMMP-11 peptide in E. coli.