Establishment of a paclitaxel resistant human breast cancer cell strain (MCF-7/Taxol) and intracellular paclitaxel binding protein analysis.

Multidrug resistance of tumours is one of the most important factors that leads to chemotherapy failure. A multidrug-resistant breast cancer cell line, MCF-7/Taxol, was established from the drug-sensitive parent cell line MCF-7. The biological properties of MCF-7/Taxol, including its drug resistance profile and profile of paclitaxel binding proteins, were analysed and compared with the parent cell line. A number of paclitaxel binding proteins were present in MCF-7 cells but absent from MCF-7/Taxol cells, namely heat shock protein 90, actinin and dermcidin precursor. The identification of differential paclitaxel binding proteins between the multidrug-resistant MCF-7/Taxol cell line and the parent drug-sensitive cell line MCF-7 provides insight into possible mechanisms involved in resistance to these chemotherapy drugs.

Protective effects of ulinastatin on intestinal injury during the perioperative period of acute superior mesenteric artery ischemia.

OBJECTIVE: This work aims to explore the protective effects of ulinastatin on intestinal injury during the perioperative period of acute superior mesenteric artery ischemia (ASMAI). PATIENTS AND METHODS: 28 patients undergoing revascularization were divided into 2 groups, with 14 cases each. The cases in the observation group (OG) were treated with ulinastatin 300,000 U intravenously 30 min before the operation, and continuously treated with 300,000 U every 4 hr thereafter until 24 hr of the operation, while those in the control group (CG) were not given the intervention of ulinastatin. Patients' circular intestinal fatty acid binding protein (I-FABP) levels were measured at the following time points to reflect the intestinal injury: 30 min before the operation, before revascularization, then 1, 12 and 24 hr after the operation. The white blood cell counting (WBC), serum alanine aminotransferase (ALT), serum creatinine (Cr), D-dimer, and serum endotoxin (ET) were also measured simultaneously for the analysis of the significance of their values with the intestinal injury. RESULTS: There were no significant differences (p > 0.05) in ischemia duration, length of the affected intestinal segments, WBC, ALT and Cr levels at the above time points between the 2 groups, and all the indicators of the 2 groups, including the mean circular I-FABP levels before the operation and the revascularization, showed no significant difference (p > 0.05). After the blood supply was restored, the I-FABP levels in OG dropped significantly as compared with those in CG. The pattern of circular ET levels appeared the similar manner as the circular I-FABP levels did. CONCLUSIONS: Our study showed a protective effects of ulinastatin on intestinal injury during the perioperative period of ASMAI, as revealed by the circular I-FABP levels which mainly happened after the blood supply was restored.