Objective To investigate the expression and the significance of the MDR1, breast cancer resistance protein, lung cancer resistance protein mRNA and corresponding proteins P-gp, BCRP and LRP in breast cancer tissues and adjacent breast tissues. Methods RT-PCR was used to exam the expression of MDR1, BCRP, LRP mRNA in 42 breast cancer tissues and 42 adjacent tissues. IHC was used to exam the expression of P-gp, BCRP and LRP in 126 breast cancer tissues and 42 adjacent tissues, and theirs relationships with clinicopathological parameters in breast cancer, axillary lymph node status and 5-year recurrence and metastasis. Results The relative expression levels of MDR1, BCRP and LRP mRNA were 0.81 ±0.17,0.78 ±0.14,0.79 ±0.13 in breast cancer tissues and 0.33 ±0.11,0.45 ±0.09,0.36 ±0.10 in adjacent tissues respectively. There were significant differences between cancer tissues and adjacent tissues ( t = 4.613, 4.850 and 8. 089, P < 0.01 ). The positivities of P-gp, BCRP and LRP were 41% ( 52/126) ,39% (49/126) and 66% (83/126) in breast cancer tissues. There were significant differences between cancer tissues and adjacent tissues (x2 = 10.147, 7.020, 27.820, P < 0.01 ). The expression of MDR1 mRNA/P-gp was significantly associated with tumor stage and lymph node metastasis ( r = 0.369,0.398, P < 0.05 ). The expression of BCRP (mRNA/protein) was significantly associated with lymph node metastasis (r = 0.355, P < 0.05 ) . The positivities of P-gp were significantly different between 39 recurrence/metastasis patients occurred in 5 years and 32 unrecurrence/nonmetastasis patients in 5 years (x2 = 11.771, P < 0.01 ). The positivities of BCRP and LRP were not significantly different in these two groups(x2 =2.261,0.078,P >0.05). The coincidence rates for expression of MDR1 ,BCRP,LRP mRNA and their proteins in breast cancer tissues were 90.48% ,92.85% and 85.71% respectively (the Kappa values were 0.806,0.751 and 0.697, P < 0.01 ). Conclusions Multidrug resistance is common in breast cancer. The three drug resistance genes and proteins are involved in the formation of multidrug resistance of breast cancer. Detection of multidrng resistance genes in breast cancer may be useful to choose chemotherapy,especially patients with P-gp positive expression are not advised to use the CAF chemotherapy.

Objective:To observe the effects of lentivirus-mediated shRNA silencing of PRL-3 gene on the proliferation, migration and invasion of lung cancer A549 cells and regulation of epithelial-mesenchymal transition (EMT) signaling pathway.Methods:Lung cancer A549 cells were transfected with lentiviral interference vector carrying PRL-3 shRNA to build a stable PRL-3-silencing cell line. The cells were divided into blank control group, NC shRNA group (negative control group) and PRL-3 shRNA group (PRL-3 inhibiting RNAi lentivirus group). CCK-8 method, colony formation assay, Transwell and invasion chamber assay were performed to detect the proliferation, migration and invasion ability of A549 cells respectively. The expressions of E-cadherin and Snail mRNA were detected by real-time fluorescent quantitative PCR.Results:The stable PRL-3-silencing cell line was successfully constructed. The knockdown efficiency of PRL-3 gene in the PRL-3 shRNA group reached 83.5%. CCK-8 method detected the proliferation ability of A549 cells, and the results showed the 24 h absorbance ( A) values of A549 cells in the blank control group, NC shRNA group and PRL-3 shRNA group were 0.296±0.008, 0.342±0.007 and 0.292±0.004, with a statistically significant diffe-rence ( F=106.300, P<0.001), and the PRL-3 shRNA group was significantly lower than the NC shRNA group ( P<0.001); at 48, 72, 96 h after transfection, the cell proliferation abilities of the PRL-3 shRNA group were also significantly inhibited. Colony formation assay showed that the numbers of colony formation in the blank control group, NC shRNA group and PRL-3 shRNA group were 166.7± 6.7, 158.0±6.1 and 119.7±1.5 ( F=67.290, P<0.001). The ability of colony formation of the PRL-3 shRNA group was significantly lower than that of the NC shRNA group ( P<0.001). The numbers of migrated cells in the blank control group, NC shRNA group and PRL-3 shRNA group were 100.0±1.9, 98.8±1.9 and 44.6±7.6 ( F=430.300, P<0.001). The migration ability of the PRL-3 shRNA group was significantly lower than that of the NC shRNA group ( P<0.001). The numbers of invaded cells in the three groups were 117.7±4.1, 113.1±6.6 and 55.6±8.4 ( F=247.200, P<0.001). The invasion ability of the PRL-3shRNA group was significantly lower than that of the NC shRNA group ( P<0.001). Real-time fluorescent quantitative PCR detection results showed that after silencing the expression of PRL-3, the relative expression level of E-cadherin mRNA in A549 cells was significantly up-regulated, and the level of Snail mRNA was significantly down-regulated. Conclusion:PRL-3 silencing can inhibit the proliferation, migration and invasion of A549 cells effectively. PRL-3 may affect the invasion of lung cancer cells through the EMT pathway.

Objective To investigate the imaging features of gastrointestinal stromal tumors (GIST) and its diagnostic value. Methods The clinical and imaging data of 41 patients with GIST proved by operation and pathology were analysed. Results Tumors located in the stomach in 20 cases, small bowel in 5 cases, rectum in 3 cases, esophagus in 2 cases and extra gastrointestinal sites in 11 cases. There were 27 malignant GIST diagnosed by imageologic examination,of them, 21 mass exceeded 5 cm in diameter, margins were vague, 19 cases had obvious adhesion or directly involved with around tissue,13 cases with obvious necrosis and cystic changes within the mass. 5 cases with metastase focus.Benign GIST in 14 cases, 11 cases were less than 5 cm in diameter, most of them had smooth margin,homogeneous density and symmetrical enhancement effect.Conclusion X-ray gastrointestinal double contrast radiography examination finds easily inside antrum and inside-and-outside antrum type GIST; CT examination offsets deficiency of general gastrointestinal radiography. It is valuable in localizing precisely, judging benign and malignantin, guiding clinical therapy and estimating prognosis for GIST.