Citations

Abstract The adaptor protein raptor is the functional identifier for mammalian target of rapamycin (mTOR) complex 1 (mTORC1), acting to target mTOR to specific substrates for phosphorylation and regulation. Using HPLC-electrospray ionization tandem mass spectrometry, we confirmed the phosphorylation of raptor at Ser696, Thr706, Ser721, Ser722, Ser855, Ser859, Ser863, Thr865, Ser877, Ser881, Ser883, and Ser884 and identified Tyr692, Ser699, Thr700, Ser704, Ser854, Ser857, Ser882, Ser886, Ser887, and Thr889 as new, previously unidentified raptor phosphorylation sites. Treatment of cells with insulin increased the phosphorylation of raptor at Ser696, Ser855, Ser863, and Thr865 and suppressed the phosphorylation of Ser722. Ser696 phosphorylation was insensitive to mTOR inhibition with rapamycin, whereas treatment of cells with the MAPK inhibitor PD98059 inhibited the insulin-stimulated phosphorylation of raptor at Ser696. In vitro incubation of raptor with p42 MAPK significantly increased raptor phosphorylation (P < 0.01), whereas phosphorylation of a Ser696Ala mutant was decreased (P < 0.05), suggesting MAPK is capable of directly phosphorylating raptor at Ser696. Mutation of Ser696 to alanine interfered with insulin-stimulated phosphorylation of the mTOR downstream substrate p70S6 kinase. Incubation of cells with the MAPK inhibitor PD98059 and the phosphatidylinositol 3-kinase inhibitor wortmannin decreased the insulin stimulated phosphorylation of raptor, suggesting that the MAPK and phosphatidylinositol 3-kinase pathways may merge at mTORC1.

Abstract The androgen receptor (AR) is the principal target for treatment of non–organ-confined prostate cancer (PCa). Androgen deprivation therapies (ADT) directed against the AR ligand–binding domain do not fully inhibit androgen-dependent signaling critical for PCa progression. Thus, information that could direct the development of more effective ADTs is desired. Systems and bioinformatics approaches suggest that considerable variation exists in the mechanisms by which AR regulates expression of effector genes, pointing to a role for secondary transcription factors. A combination of microarray and in silico analyses led us to identify a 158-gene signature that relies on AR along with the transcription factor SRF (serum response factor), representing less than 6% of androgen-dependent genes. This AR-SRF signature is sufficient to distinguish microdissected benign and malignant prostate samples, and it correlates with the presence of aggressive disease and poor outcome. The AR-SRF signature described here associates more strongly with biochemical failure than other AR target gene signatures of similar size. Furthermore, it is enriched in malignant versus benign prostate tissues, compared with other signatures. To our knowledge, this profile represents the first demonstration of a distinct mechanism of androgen action with clinical relevance in PCa, offering a possible rationale to develop novel and more effective forms of ADT. Cancer Res; 71(5); 1978–88. ©2011 AACR.

The purpose of this study was to evaluate the incidence and durability of additional proximal cuffs during endovascular abdominal aortic aneurysm repair (EVAR). A retrospective review of 90 EVAR patients was conducted. Postoperative survival, proximal sealing zone–related complications, and secondary procedures were analyzed. Additional proximal cuffs were used in 11%. Their use did not affect postoperative survival ( p = .58), type I endoleak rate (4.4%; p = .19), or the need for sealing zone–related secondary procedures (6.3%; p = .38) compared with patients without cuff placement but was related to a higher cumulative graft migration rate (2.2% overall p = .02). Two patients (2.5%; p = .79) underwent conversion to open surgery, both for proximal sealing zone–related complications. Application of proximal cuffs appears to be an effective intraoperative adjunctive procedure to achieve a proximal seal during EVAR, with favorable midterm results. However, the risk of late endograft migrations may be elevated in this group.

AbstractPurposeWe assessed risk factors for splenic injury during colectomy and associated outcomes for a 15‐year period at a single institution.MethodsAll adult general surgery patients who sustained a splenic injury during colectomy at our institution from 1992 to 2007 were retrospectively identified and matched 1:1 to controls without splenic injury. Putative risk factors were assessed using paired univariate analysis and conditional logistic regression. Differences in short‐ and long‐term mortality were assessed using the log‐rank test. Results are reported as a proportion, median, or odds ratio [OR (95% confidence intervals)].ResultsA total of 118 patients were included: 59 patients with splenic injury and 59 control patients. Statistically significant risk factors for splenic injury during colectomy found on univariate analysis included: splenic flexure mobilization, OR 21.00 (2.82–156.12); Charlson comorbidity index ≥5, OR 3.17 (1.26–7.93); ASA class ≥3, OR 5.33 (1.55–18.3); and nonelective surgery, OR 5.00 (1.1–22.82). On multivariate analysis, only splenic flexure mobilization was independently associated with increased risk of splenic injury (OR 18.4 (2.1–161); p = 0.0085). Splenic injured patients trended toward decrease survival both at 30 days (98 vs. 88%; p = 0.06) and at 5 years (58 vs. 55%), with a hazard ratio of 1.6 (1.0, 2.6; p = 0.05).ConclusionsSplenic flexure mobilization is the primary risk factor for splenic injury during colectomy, independent of other factors, such as higher ASA class, Charlson score, and nonelective surgery. Splenic injury during colectomy has an increased risk of death in both the short‐ and long‐term.