According to data from 2015 Open Payments reports, 48% of physicians were reported to have received a total of $2.4 billion in industry-related payments, primarily general payments, with a higher likelihood and higher value of payments to physicians in surgical vs primary care specialties and to male vs female physicians.

Nitrogen-containing bisphosphonate drugs inhibit bone resorption by inhibiting FPP synthase and thereby preventing the synthesis of isoprenoid lipids required for protein prenylation in bone-resorbing osteoclasts. NE10790 is a phosphonocarboxylate analogue of the potent bisphosphonate risedronate and is a weak antiresorptive agent. Although NE10790 was a poor inhibitor of FPP synthase, it did inhibit prenylation in J774 macrophages and osteoclasts, but only of proteins of molecular mass ϳ22-26 kDa, the prenylation of which was not affected by peptidomimetic inhibitors of either farnesyl transferase (FTI-277) or geranylgeranyl transferase I (GGTI-298). These 22-26-kDa proteins were shown to be geranylgeranylated by labelling J774 cells with [ 3 H]geranylgeraniol. Furthermore, NE10790 inhibited incorporation of [ 14 C]mevalonic acid into Rab6, but not into H-Ras or Rap1, proteins that are modified by FTase and GGTase I, respectively. These data demonstrate that NE10790 selectively prevents Rab prenylation in intact cells. In accord, NE10790 inhibited the activity of recombinant Rab GGTase in vitro, but did not affect the activity of recombinant FTase or GGTase I. NE10790 therefore appears to be the first specific inhibitor of Rab GGTase to be identified. In contrast to risedronate, NE10790 inhibited bone resorption in vitro without markedly affecting osteoclast number or the F-actin "ring" structure in polarized osteoclasts. However, NE10790 did alter osteoclast morphology, causing the formation of large intracellular vacuoles and protrusion of the basolateral membrane into large, "domed" structures that lacked microvilli. The anti-resorptive activity of NE10790 is thus likely due to disruption of Rabdependent intracellular membrane trafficking in osteoclasts.

Background and Purpose Brain radiotherapy is limited in part by damage to white matter, contributing to neurocognitive decline. We utilized diffusion tensor imaging (DTI) with multiple b-values (diffusion weightings) to model the dose-dependency and time course of radiation effects on white matter. Materials and Methods Fifteen patients with high-grade gliomas treated with radiotherapy and chemotherapy underwent MRI with DTI prior to radiotherapy, and after months 1, 4-6, and 9-11. Diffusion tensors were calculated using three weightings (high, standard, and low b-values) and maps of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λ‖), and radial diffusivity (λ⊥) were generated. The region of interest was all white matter. Results MD, λ‖, and λ⊥increased significantly with time and dose, with corresponding decrease in FA. Greater changes were seen at lower b-values, except for FA. Time-dose interactions were highly significant at 4-6 months and beyond (p < .001), and the difference in dose response between high and low b-values reached statistical significance at 9-11 months for MD, λ‖, and λ⊥ (p < .001, p < .001, p = .005 respectively) as well as at 4-6 months for λ‖ (p = .04). Conclusions We detected dose-dependent changes across all doses, even <10 Gy. Greater changes were observed at low b-values, suggesting prominent extracellular changes possibly due to vascular permeability and neuroinflammation.

Purpose Radiation-induced cognitive deficits may be mediated by tissue damage to cortical regions. Volumetric changes in cortex can be reliably measured using high-resolution magnetic resonance imaging (MRI). We used these methods to study the association between radiation therapy (RT) dose and change in cortical thickness in high-grade glioma (HGG) patients. Methods and Materials We performed a voxel-wise analysis of MR imaging from 15 HGG patients who underwent fractionated partial brain RT. Three-dimensional MRI was acquired pre- and 1-year post-RT. Cortex was parcellated with well-validated segmentation software (Freesufer). Surgical cavities were censored. Each cortical voxel was assigned a change in cortical thickness between time points, RT dose value, and neuroanatomic label by lobe. Effect of dose, neuroanatomic location, age, and chemotherapy on cortical thickness was tested using linear mixed effects (LME) modeling. Results Cortical atrophy was seen after 1-year post RT, with greater effects at higher doses. Estimates from LME modeling showed that cortical thickness decreased by −0.0033 mm (p<0.001) for every 1 Gy increase in RT dose. Temporal and limbic cortex exhibited the largest change in cortical thickness per Gy, compared to other regions (p<0.001). Age and chemotherapy were not significantly associated with cortical thickness change. Conclusions We found dose-dependent thinning of the cerebral cortex, with varying neuroanatomical regional sensitivity, one year after fractionated partial brain RT. The magnitude of thinning parallels one-year atrophy rates seen in neurodegenerative diseases, and may contribute to cognitive decline following high-dose RT.

Background: Industry-physician collaboration is critical for anticancer therapeutic development, but financial relationships introduce conflicts of interest. We examined the specialty variation and context of physician payments and ownership interest among oncologists. Methods: We performed a population-based multivariable analysis of 2014 Open Payments reports of industry payments to US physicians matched to physician and practice data, including sex, specialty, practice location, and sole proprietor status. Payment data were aggregated per physician and compared by specialty (medical, radiation, surgical, and nononcology), and practice location linked with spending level (low, average, and high). Primary outcomes included likelihood, mean annual amount, and number of general payments. Secondary outcomes included likelihood of holding ownership interests and receipt of royalty/license payments. Estimates for each outcome were determined using multivariable models, including logistic regression for likelihood and linear regression with gamma distribution and log-link for value, adjusted for physician specialty, sex, sole proprietor status, and practice spending. All statistical tests were two-sided. Results: In 2014, there were 883 438 physicians, including 22 712 oncologists, licensed to practice in the United States. Among oncology specialties, 52.4% to 63.0% of physicians received a general payment in 2014, totaling $76 million, $4 million, and $5 million to medical, radiation, and surgical oncology, respectively. The median annual per-physician payment to medical oncologists was $632 (IQR ¼ 136-2500), compared with $124 (IQR ¼ 39-323) in radiation oncology and $250 (IQR ¼ 84-1369) in surgical oncology. After controlling for physician and practice characteristics, oncologists were 1.09 to 1.75 times as likely to receive a general payment compared with nononcologists (overall P < .001). There was a 67.6% difference (95% confidence interval [CI] ¼ 63.6 to 71.5, P < .001) in the mean annual value of payments between medical oncology and nononcology specialties (vs À92.7%, 95%CI ¼ À100.2 to À85.0, P < .001] for radiation oncology). Medical and radiation oncologists were more likely to hold ownership interest (adjusted OR ¼ 3.72, 95% CI ¼ 3.22 to 4.27, and 2.27, 95% CI ¼ 1.65 to 3.03, respectively, P < .001 both comparisons). Conclusions: In 2014, industry-oncologist financial relationships were common, and their impact on oncology practice should be further explored.