AbstractIntroductionSpinal cord stimulators (SCS) are used to treat various chronic pain states. Establishing patient outcomes in terms of pain control, opioid medication use, and overall satisfaction is vital in maintaining SCS's role in clinical practice.MethodsAll patients who underwent SCS implantation between January 2001 and December 2011 at a tertiary academic pain medicine center were included if he or she underwent permanent cervical or thoracolumbar dorsal column SCS implantation and age was 18 or greater. For the 199 patients who met inclusion criteria, data were collected retrospectively. Preimplant information included indication for implantation, Numeric Rating Scale (NRS) score, and dose in oral morphine equivalents (OME). Postimplant NRS score was recorded at 6 months and 1 year. OME requirement and patient satisfaction were determined at 1 year postimplantation.ResultsThis data set showed an overall decrease in OME requirements and NRS scores at both 6 months and 1 year. These differences were statistically significant (P < 0.01) compared to preimplantation values. Additionally, 84.27% of patients were satisfied with their implants at 1 year. Patient outcomes were analyzed further in respect to implant indication; groups included failed back surgery syndrome (FBSS), complex regional pain syndrome (CRPS), angina, and other. For all groups, there were statistically significant (P < 0.01) decreases in NRS scores at 6 months and 1 year. In the FBSS and CRPS groups, statistically significant (P < 0.02) decreases in OME usage existed.ConclusionRetrospective review of patients with spinal cord stimulators revealed OME reduction at 1 year for those patients in the FBSS and CRPS groups; patient satisfaction at 1 year and NRS score reduction at 6 months and 1 year were statistically significant for all groups.
Abstract LB-183: Metformin use does not increase survival of pancreatic cancer patients: A cautionary lesson
Abstract Background: Epidemiologic studies have suggested that metformin use is associated with cancer death reduction. The results for pancreatic ductal adenocarcinoma (PDAC) are inconsistent. Retrospective studies of cancer survival may potentially have unintended biases; due to complexities of diabetes management, metformin use exposure is commonly categorized as simply “yes/no.” Nevertheless, in part based on epidemiologic studies, there are at least 20 open cancer clinical trials that include metformin in a treatment arm. We aimed to study metformin use and survival of patients with PDAC, addressing potential inherent biases. Methods: A retrospective cohort study for the years 2000-2011 was conducted using the patient database of the Mayo Clinic Specialized Programs of Research Excellence (SPORE) in Pancreatic Cancer. 1,360 PDAC patients (59% male; mean age 67) with diabetes were studied; overall survival was the primary outcome. Initiation and duration of metformin use was carefully abstracted from medical records. Patients were categorized into 5 groups based on metformin initiation: (A) Never used, n = 908 (reference group); (B) Metformin started >1 year prior to PDAC diagnosis, n = 84; (C) Metformin started within 1 year prior to PDAC diagnosis, n = 212; (D) Metformin started <30 days post-PDAC diagnosis, n = 104; (E) Metformin started >30 days post PDAC diagnosis, n = 34. Hazard ratios (HR) and 95% confidence intervals (C.I.) for survival differences between groups were computed using Cox proportional hazards models, adjusting for age, sex, disease stage, body mass index, and diagnosis year group. Results: Median survival of patients in Groups B-E was 292 days compared to 308 for Group A; this was not significantly different. However, among 413 resectable patients, metformin users appeared to survive longer than non-users (782 vs. 612 days, p = 0.07). Survival in each group was 308, 245, 249, 243 and 818 days, respectively. Because Group E had already survived >30 days, a bias existed. With Group E excluded, there was no survival difference among the other 4 groups (p = 0.18). Compared to Group A, HR and 95% C.I. for metformin use were 1.08 (0.85-1.37), 0.99 (0.85-1.17), 1.04 (0.83-1.31) and 0.49 (0.33-0.74), for Group B-E, respectively. Conclusions: Our thorough analysis suggests that metformin use does not improve survival of patients with PDAC. The benefit of metformin was observed only in patients who started metformin post-PDAC diagnosis; however, there is an inherent survival bias in this group of patients. Studies of medication exposure and cancer survival warrant very careful and detailed data collection. Researchers should exercise caution when initiating clinical trials based on retrospective epidemiologic studies. Citation Format: Roongruedee Chaiteerakij, David B. Zhen, Patrick A. Burch, Kari G. Chaffee, William R. Bamlet, Ann L. Oberg, Lewis R. Roberts, Gloria M. Petersen. Metformin use does not increase survival of pancreatic cancer patients: A cautionary lesson. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-183. doi:10.1158/1538-7445.AM2015-LB-183
Abstract Background: The transcription factor Krüppel-like factor 5 (KLF5) is essential for normal homeostasis, stemness, and tumorigenesis. Typically, KLF5 functions as a transcriptional activator, including in esophageal epithelia where KLF5 promotes keratinocyte proliferation and migration by activating EGFR and ILK, respectively, and prevents transformation by activating Notch1. Yet, the function of KLF5 is context dependent, and mutation of the tumor suppressor p53 switches KLF5 from a transcriptional activator to a repressor of p21Waf1/Cip1 and from pro-proliferative to anti-proliferative. Interestingly, KLF5 also inhibits p53 itself, though the mechanism of this inhibition is unknown. We hypothesized that the functional switch of KLF5 from transcriptional activator to repressor involves the recruitment of a co-repressor. Methods: Primary human esophageal keratinocytes immortalized with hTERT were stably infected with inducible lentivirus containing shRNA against KLF5 or Sin3A. p53 mRNA and protein levels were assessed by real-time quantitative PCR and Western blotting, respectively, and p53 protein stability was evaluated by pulse-chase experiments. We employed ChIP across a 4 kb region on the p53 gene, from 2 kb upstream to 2 kb downstream of the transcription start site, to identify the region of KLF5 binding on p53. Promoter activity was assessed with a series of luciferase reporters containing varying lengths of p53 and its upstream regulatory region. Protein-protein interaction was examined by co-IP. Results: KLF5 knockdown significantly increased p53 both at the mRNA and protein levels. In unstressed cells p53 protein undergoes rapid degradation such that p53 levels are typically low. Yet, with KLF5 knockdown, despite increased p53 protein levels, we saw no changes in p53 protein stability. By ChIP, we identified a region of KLF5 binding to p53 between -600 to -356 bp upstream of the transcription start site. Several other KLF family members can interact with the co-repressor Sin3A, and we found that Sin3A also complexed with KLF5 in human primary esophageal keratinocytes. Knockdown of Sin3A abolished the inhibitory effect of KLF5 on p53, resulting in elevated p53 expression, growth inhibition, and increased apoptosis. Conclusion: KLF5 transcriptionally represses p53 via the co-repressor Sin3A. Thus, KLF5 promotes cell proliferation in normal keratinocytes by both activating pro-growth signals and inhibiting the brake machinery of the cell cycle. Citation Format: Yizeng Yang, Taicheng Zhou, Zhen Zong, Gwen Lomberk, Raul Urrutia, Jonathan Katz. Regulation of p53 function by KLF5. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2087. doi:10.1158/1538-7445.AM2015-2087
Diabetes is Associated with Worse Executive Function in Both Eastern and Western Populations: Shanghai Aging Study and Mayo Clinic Study of Aging
The Benefits and Harms of Systemic Dehydroepiandrosterone (DHEA) in Postmenopausal Women With Normal Adrenal Function: A Systematic Review and Meta-analysis
AbstractContext:Exogenous dehydroepiandrosterone (DHEA) therapy has been proposed to replenish the depletion of endogenous DHEA and its sulfate form, which occurs with advancing age and is thought to be associated with loss of libido and menopausal symptoms.Objective:We conducted a systematic review and meta-analysis to summarize the evidence supporting the use of systemic DHEA in postmenopausal women with normal adrenal function.Methods:We searched MEDLINE, EMBASE, PsycInfo, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus through January 2014. Pairs of reviewers, working independently, selected studies and extracted data from eligible randomized controlled trials (RCTs). We used the random-effects model to pool across studies and evaluated heterogeneity using the I2 statistic.Results:We included 23 RCTs with moderate to high risk of bias enrolling 1188 women. DHEA use was not associated with significant improvement in libido or sexual function (standardized mean difference, 0.35; 95% confidence interval, −0.02 to 0.73; P value = .06; I2 = 62%). There was also no significant effect of DHEA on serious adverse effects, serum lipids, serum glucose, weight, body mass index, or bone mineral density. This evidence warranted low confidence in the results, mostly due to imprecision, risk of bias, and inconsistency across RCTs.Conclusions:Evidence warranting low confidence suggests that DHEA administration does not significantly impact sexual symptoms or selected metabolic markers in postmenopausal women with normal adrenal function.
Frequencies and geographic distributions of genetic mutations in transthyretin‐ and non‐transthyretin‐related familial amyloidosis
Inherited forms of amyloidosis are rare; of these, transthyretin‐related (ATTR) is the most common, but non‐ATTR has been described as well. We studied a large case series of ATTR and a small series of non‐ATTR to better determine the mutation frequencies and geographic distributions of these inherited forms of amyloidosis in the United States. We performed a retrospective cross‐sectional study of 284 ATTR and non‐ATTR patients seen at Mayo Clinic in Rochester, Minnesota, from 1 January 1970 through 29 January 2013. Mutations were identified by DNA sequencing, restriction fragment length polymorphism, or mass spectroscopy. The genetic testing method was unknown for several patients, but a small proportion were identified by family history or by classical clinical presentation associated with a specific mutation. The most common ATTR mutations were Thr60Ala (24%), Val30Met (15%), Val122Ile (10%), and Ser77Tyr (5%). Non‐ATTR mutations included gelsolin (n = 3), apolipoprotein A‐I (n = 6), apolipoprotein A‐II (n = 1), fibrinogen A‐α (n = 9), and lysozyme (n = 1). Although rare, ATTR and, to a lesser extent, non‐ATTR are prevalent in the United States and should be considered for patients presenting in the appropriate clinical context.
Tacrolimus/sirolimus vs tacrolimus/methotrexate as GVHD prophylaxis after matched, related donor allogeneic HCT
Key Points Tac/Sir prophylaxis provides equivalent GVHD-free survival when compared with Tac/Mtx in MRD transplantation. Tac/Sir is associated with more rapid engraftment and reduced oropharyngeal mucositis after MRD transplantation.