Objective To explore the imaging diagnostic value of gastrointestinal stromal tumor(GIST).Methods The retrospective study on GIST proved by operation and pathology in 11 cases was done.There were pneumobarium double contrast examination in 10 cases,CT scanning in 4 cases,superior mesenteric ateriography in 2 cases and fiberoptic endoscopy in 7 cases.Results The locations of tumors at gastric were 7 cases,intestinal 2,lipper and row oseophagus to gastric cardiac in 1,respectively.The detective rate of GIST was 100%,75%,100% and 100% respectively by pneumobarium double contrast examination,CT,arteriography and fiberoptic endoscopy.Conclusion Pneumobarium double contrast examination and fiberoptic endoscopy are important methods for diagnosis of GIST.CT and arteriography can better show the location of tumors and differential diagnosis of benign and malignant of tumor.

BACKGROUNDLung cancer cell lines A549 and NCI-H446 with different radiosensitivity to ionizing radiation (IR) have different MDM2 gene expression status, which may contribute to the radioresistance of cells. The aim of this study is to use small interfering RNA (siRNA) targeting MDM2 to investigate the influence of MDM2 gene silencing on radioresponse of A549 cell.

METHODSPlasmid targeting MDM2 was constructed with pPUR/U6 vector and oligonucleotide designed according to the sequence of effective antisense oligonucleotides and principles of siRNA design. A549 cells were transfected by Lipofectamine™ 2000. MDM2 expression in A549 cells was detected by RT-PCR and Western blot. Radiation-mediated cell killing was detected by flow cytometry.

RESULTSTwo out of three siRNA plasmids were constructed successfully. siRNA transfection resulted in downregulaton of MDM2 expression of A549 cells on mRNA and protein levels. After treated with siRNA, radiation-mediated cell killing of A549 cells was significantly increased (P < 0.01).

CONCLUSIONSThe results support the hypothesis that MDM2 gene is a candidate for radioresistance in A549 cells. siRNA targeting to MDM2 can enhance the radiation-mediated cell killing of A549 cells.

Objective To investigate the changes of quantitative parameters of dynamic enhanced CT in non-small cell lung cancer before and after targeted therapy,and compare them with the traditional evaluation criteria,in order to find the parameters which can be exploited for timely,objective evaluation of the effect of targeted therapy.Methods The study included 21 patients with targeted therapy who had received dynamic enhanced CT before and after treatment.Enhancement time-density curves were obtained based on the CT values of the lesion at individual time points,and the functional indices:peak height (PH),the time to peak height (Tp),the ratio of PH of the mass to aorta (M/A) and perfusion value were calculated.The effects of the treatment on these indices were evaluated and compared with the effect of the treatment on lesion diameter. Results Twenty-one patients had 33 rechecking results. There was a statistically significant agreement between lesion diameter-based treatment evaluation and perfusion-based treatment evaluation ( U =8.761,P ＜ 0.01 ). The perfusion value decreased in patients with disease regression[before treatment:(0.28 ±0.11 ) ml · min-1 · ml-1,after targeted therapy(0.18 ±0.09) ml ·min-1 · ml-1,t =- 3.2722,P =0.0042],but increased in patients with disease progression[before treatment(0.21 ±0.08) ml · min-1 · ml-1,after targeted therapy:(0.34 ±0.11 ) ml · min-1 · ml-1,t =2.6064,P =0.0403].Conclusions On dynamic enhanced CT in non-small cell lung cancer patients after targeted therapy,perfusion value changed in the same trend as the diameter of tumor.The effectiveness of targeted therapy may be evaluated by perfusion value changes.

Background and objective Gemcitabine and taxanes are effective agents commonly used in advanced squamous lung cancer. hTe best treatment sequence, however, is unclear to our knowledge. So we conducted this retrospective study in order to compare the effcacy and toxicities of ifrst-line Gemcitabine+/-platinum followed by second-line taxanes+/-platinum with the reverse sequence. Methods We totally analyzed 105 patients with stage IIIb-IV squamous lung cancer in our retrospective study. hTere were 49 patients receiving gemcitabine+/-platinum ifrst-line followed by taxanes+/-plati-num second-line (G-T group), and 56 patients receiving taxanes+/-platinum ifrst-line followed by gemcitabine+/-platinum second-line (T-G group). hTe primary endpoint of the study was overall survival (OS), and the secondary endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR) and toxicities. Results hTe me-dian OS were 18.5 mo in G-T group and 19.0 mo in T-G group (P=0.520). hTe median PFS1 was 5.0 mo and 4.0 mo with ifrst-line gemcitabine+/-platinum and taxanes+/-platinum, respectively (P=0.584). hTe median PFS2 was 2.7 mo and 2.5 mo with second-line gemcitabine+/-platinum and taxanes+/-platinum (P=0.432). hTe ORR1 of G-T group and T-G group were 36.73%and 33.92%(P=0.577), and DCR1 were 79.59%and 89.29%(P=0.186);the ORR2 of G-T group and T-G group were 4.08%and 5.36%(P=0.085), and DCR2 were 51.02%and 66.07%, respectively (P=0.118). Hematologic toxicities was more frequent in G-T group, the patients experienced more grade 3-4 lower hemoglobin (P=0.027) and thrombocytopenia (P=0.002). Conclusion hTe effcacy of ifrst line gemcitabine+/-platinum followed by second line taxanes+/-platinum and the reverse sequence was similar, and the toxicities was tolerable. Both sequential patterns were effective in advanced squamous lung cancer.

Background and objective Small-cell lung cancer (SCLC) is an aggressive disease for which the mainstay of treatment is cytotoxic chemotherapy. Despite good initial responses most patients will relapse or progress atfer the ifrst-line therapy. hTe evidence of a beneift from second-line chemotherapy is limited in patients with relapsed/advanced SCLC. Some drugs are recommended by guidelines, but more regimens are formulated based on experience in clinical. So we conducted this retrospective study in order to compare the effcacy and safety of different second-line treatment regimens. Methods We totally analyzed 309 patients received second-line treatment in our retrospective study. 157 patients received best supportive care (BSC), and the rest 152 patients received second-line chemotherapy. hTe Kaplan-Meier method survival curves and Log-rank test were used to analysis the differences among different groups. hTe endpoints were objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). Results Patients administered second-line chemotherapy lived signiifcantly longer, with a total OS from ifrst-line therapy of 11.5 mo compared to 6.0 mo in patients with best supportive care alone (P<0.001), and the ORR, DCR, PFS and OS of the former (including the sensitive dis-ease and resistance/refractory disease patients) were obviously better than that of the latter. hTe ORR and DCR of the patients who received second-line chemotherapy is 39.5%and 59.2%, respectively. hTe median PFS and OS from second-line chemo-therapy were 3.3 mo and 5.3 mo. hTe patients who received second-line chemotherapy were divided by types of second-line regimens. hTe sensitive disease patients were from group A (VP-16-based rechallenge) and group B1 (CPT-11-based regimen). hTe ORR of the two groups were 48.6%and 35.3%, and the DCR were 68.6%and 58.8%, respectively. hTere was no statistically signiifcant difference (P=0.264;P=0.400). hTe median PFS from second-line chemotherapy of the two groups were 4.0 mo and 3.0 mo, and the second-line median OS were 6.5 mo and 4.5 mo. hTere was no statistic difference (P=0.432;P=0.508). hTe resistance/refractory disease patients were divided into group B2 (CPT-11-based regimen), group C (PTX/DXL-based regi-men) and group D (TPT-based regimen). hTere was no statistic difference in second-line ORR, DCR and median PFS among the three groups (P value is 0.521, 0.528 and 0.775, respectively);hTe median OS from second-line chemotherapy of the group D is longer than that of group B2 and group C, with statistical difference (P=0.043;P=0.030). hTe differences of grade III-IV hematologic toxicities among the four subgroups were not statistically different. hTe incidence of diarrhea in non-hematologic toxicities in patients who received irinotecan as second-line chemotherapy was higher than other three subgroups (P=0.029). Conclusion Patients who progressed atfer the completion of ifrst-line chemotherapy can gain survival beneift. hTe response and the PFS of the different second-line chemotherapies were similar. hTe patients who received the TPT-based regimen may gain longer overall survival than other resistance/refractory disease patients.