Construction and identification of conditional islet βcell DEPTOR knockout mice / 实用医学杂志

Objective To study the function of Deptor gene on the regulation of diabetes mellitus in suc-cessfully constructed and identified islet β-cell conditionally DEPTOR knockout mice model. Method By cross-breeding Deptorflox/floxmice with Cre mice expressed conditional specifically in pancreatic β-cell,Deptorflox/+Cre+/-mice were acquired and their genotypic identification was then performed. As the mice model of this study, Deptorflox/floxCre+/-mice were generated by crossing Deptorflox/+Cre+/-mice with Deptorflox/floxmice.Genotypic identifica-tion was performed by PCR at the age of 3 weeks. Tamoxifen was administered through intraperitoneal injection to induce the activation of the Cre recombination in islet beta cells of 8 weeks mice.Double immunofluorescence label-ing was then applied to identify the knockout effect of DEPTOR gene. Results Ten Islets Deptor knockout mice models were successfully acquired after 10-month cross-breeding. Validated genotype by PCR analysis were Deptorflox/floxCre+/- and double immunofluorescence labeling showed a significant difference between knockout mice and rodent controls. Conclusion Our study successfully constructs the islets conditionally Deptor deleted mice model by using Cre-loxp recombination system,providing a promising appliable animal model for study of dia-betes mellitus pathogenetic mechanism.

Expression and prognostic effect of DEPTOR in rectal carcinoma / 局解手术学杂志

Objective To clarify the expression of DEPTOR in rectal cancer,and to further explore the relationship between the expres-sion level of DEPTOR and histopathology and prognosis,in order to provide reference for the clinical diagnosis and treatment of rectal cancer. Methods The clinical data of 102 patients who underwent radical resection of rectal cancer in our hospital from January 2011 to January 2013 were analyzed retrospectively.The expression of DEPTOR in cancer tissues and adjacent tissues were evaluated by immunohistochemis-try and immunoblotting.The patients were divided into high expression group and low expression group by the median value of integrated opti-cal density(IOD);the relationship between the expression level of DEPTOR and clinical,histopathology and prognosis was analyzed. Results The results ofImmunohistochemistry and immunoblotting showed that the expression level of DEPTOR in cancer tissues was higher than that in adjacent tissues,the differences were significant(P<0.05). Univariate analysis showed that there was no significant differences in gender, age,and BMI(P>0.05),and there were significant differences in tumor diameter,T stage,N stage,and differentiation between the high-ex-pression and low-expression group (P<0.05).The independent influencing factors of DEPTOR expression was analyzed by the Logistic re-gression model,which showed that T stage and tumor diameter were independent influencing factors of high expression of DEPTOR.Compared with low expression group,the serum CEA level in patients with high expression group was higher,the differences was statistically significant ( P < 0.05 ). There was no significant difference in serum CA199 level between the expression group and the low expression group (P>0.05).Spearman correlation analysis showed that the expression level of DEPTOR was positively correlated with serum CEA level in rectal cancer patients (r=0.509,P<0.01).Compared with low expression group,the 5-year cumulative recurrence rate and the 5-year cumulative mortality rate in the high-expression group of DEPTOR were higher,the differences were statistically significant ( P <0.05). Conclusion DEPTOR is highly expressed and is associated with the degree of disease progression in rectal cancer,its elevation suggests a poor prognosis.

Molecular Mechanisms Underlying the Time-dependent Autophagy and Apoptosis Induced by Nutrient Depletion in Multiple Myeloma: a Pilot Study / 华中科技大学学报（医学）（英德文版）

This study explored the molecular mechanisms underlying the time-dependent autophagy and apoptosis induced by nutrient depletion in human multiple myeloma cell line RPMI8226 cells.RT-PCR and qRT-PCR were used to evaluate the transcriptional levels of Deptor,JNK1,JNK2,JNK3,Raf-1,p53,p21 and NFκB1 at 0,6,12,18,24 and 48 h after nutrient depletion in RPMI8226 cells.We found that transcriptional levels of Deptor were increased time-dependently at 0,6,12 and 18 h,and then decreased.Its alternation was consistent with autophagy.Transcriptional levels of Raf-1,JNK1,JNK2,p53 and p21 were increased time-dependently at 0,6,12,18,24 and 48 h accompanying with the increase of apoptosis.Transcriptional levels of NFκB 1 at 6,12,18,24 and 48 h were decreased as compared with 0 h.It was suggested that all the studied signaling molecules were involved in cellular response to nutrient depletion in RPMI8226 cells.Deptor contributed to autophagy in this process.Raf-1/JNK/p53/p21 pathway may be involved in apoptosis,and NFκB1 may play a possible role in inhibiting apoptosis.It remained to be studied whether Deptor was involved in both autophagy and apoptosis.