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Cyclin D1 is an oncogene frequently overexpressed in human cancers that has a dual function as cell cycle and transcriptional regulator, although the latter is widely unexplored. Here, we investigated the transcriptional role of cyclin D1 in lymphoid tumor cells with cyclin D1 oncogenic overexpression. Cyclin D1 showed widespread binding to the promoters of most actively transcribed genes, and the promoter occupancy positively correlated with the transcriptional output of targeted genes. Despite this association, the overexpression of cyclin D1 in lymphoid cells led to a global transcriptional downmodulation that was proportional to cyclin D1 levels. This cyclin D1-dependent global transcriptional downregulation was associated with a reduced nascent transcription and an accumulation of promoter-proximal paused RNA polymerase II (Pol II) that colocalized with cyclin D1. Concordantly, cyclin D1 overexpression promoted an increase in the Poll II pausing index. This transcriptional impairment seems to be mediated by the interaction of cyclin D1 with the transcription machinery. In addition, cyclin D1 overexpression sensitized cells to transcription inhibitors, revealing a synthetic lethality interaction that was also observed in primary mantle cell lymphoma cases. This finding of global transcriptional dysregulation expands the known functions of oncogenic cyclin D1 and suggests the therapeutic potential of targeting the transcriptional machinery in cyclin D1-overexpressing tumors., Introduction Cyclin D1 plays a central role in cell cycle regulation, and it is frequently upregulated in cancer by different genomic alterations, including amplifications in breast and respiratory tract tumors [...]

Background: The study presents a comparison of the glucose-lowering effects, glycemic variability, and insulin doses during treatment with insulin degludec or insulin glargine., Methods: In this open-label, single-center, 2-way crossover study, 13 Japanese diabetic outpatients in the insulin-dependent state on basal-bolus therapy were assigned to receive either insulin glargine followed by insulin degludec, or insulin degludec followed by insulin glargine. Basal insulin doses were fixed in principle, and patients self-adjusted their bolus insulin doses. Seventy-two-hour continuous glucose monitoring was performed 2 weeks after switching the basal insulin., Results: Mean blood glucose (mg/dL) was not significantly different between insulin degludec and insulin glargine over 48 hours (141.8 ± 35.2 vs 151.8 ± 43.3), at nighttime (125.6 ± 40.0 vs 124.7 ± 50.4), or at daytime (149.3 ± 37.1 vs 163.3 ± 44.5). The standard deviation (mg/dL) was also similar (for 48 hours: 48.9 ± 19.4 vs 50.3 ± 17.3; nighttime: 18.7 ± 14.3 vs 13.7 ± 6.7; daytime: 49.3 ± 20.0 vs 44.3 ± 17.7). Other indices of glycemic control, glycemic variability, and hypoglycemia were similar for both insulin analogs. Total daily insulin dose (TDD) and total daily bolus insulin dose (TDBD) were significantly lower with insulin degludec than with insulin glargine (TDD: 0.42 ± 0.20 vs 0.46 ± 0.22 U/kg/day, P = .028; TDBD: 0.27 ± 0.13 vs 0.30 ± 0.14 U/kg/day, P = .036)., Conclusions: Insulin degludec and insulin glargine provided effective and stable glycemic control. Insulin degludec required lower TDD and TDBD in this population of patients., (© 2014 Diabetes Technology Society.)