The impact of statin use on the efficacy of abiraterone acetate in patients with castration‐resistant prostate cancer

Background

Statins compete with DHEAS for influx through the SLCO2B1 transporter, which may prolong time to progression (TTP) on androgen deprivation therapy. Abiraterone acetate (AA) may also undergo SLCO‐mediated transport. Based on preclinical findings showing antagonism, we hypothesized that statins may compete with AA for influx via SLCO2B1 and could negatively impact drug efficacy.

Methods

We queried two institutional clinical databases (Dana‐Farber Cancer Institute [DFCI], Johns Hopkins University [JHU]) for CRPC patients treated with AA. Treatment duration was a surrogate for TTP. Associations between statin use and AA duration were estimated using the Kaplan‐Meier method. Multivariable Cox regression modeling adjusted for known prognostic factors.

Results

Of the 224 DFCI and 270 JHU patients included, the majority (96%) had metastatic disease. Nearly half (41% and 45%) were statin users. In the DFCI cohort, there was a trend toward longer AA duration in statin users: 14.2 versus 9.2 months (HR 0.79, 95%CI: 0.57‐1.09, P = 0.14). There was no association between statin use and AA duration in the JHU cohort: 8.3 versus 8.0 months (HR 0.89, 95%CI: 0.69‐1.16, P = 0.38) in the statin users versus non‐users, except for a trend in patients that had not previously received docetaxel or enzalutamide (HR 0.79; 95%CI: 0.57‐1.10).

Conclusions

Contrary to our initial hypothesis, there was a trend toward longer (rather than shorter) AA duration in statin users in the entire DFCI cohort and in the enzalutamide‐ and docetaxel‐naïve JHU patients. Together, these results do not support the hypothesis that statins interfere with AA efficacy.     

Investigation of the endocrine system in extended longevity lines of Drosophila melanogaster

There is a complete absence of information about the endocrinology of Drosophila melanogaster in relation to genetic-based differential longevity in this model species. In the present study, aspects of the endocrine system of D. melanogaster were investigated in selected and control lines characterized by relative differences in life span. By using extracts from whole bodies, steroid hormone (ecdysteroid) titers were determined by radioimmunoassay in all replicate selected and control lines on the first and fourth day of adult life. The results suggest that ecdysteroid titers were relatively reduced on the first day post-eclosion in females from the long-lived lines, but this difference was not present on the fourth day posteclosion. The reduction in early-age ecdysteroid titers in long-lived females might be related to the decrease in early-age fecundity in the selected lines. There was no difference between line types in male ecdysteroid titers on either day post-eclosion. Two classes of enzymes that act on juvenile hormone were also investigated in the present study. Esterase and epoxide hydrolase activity on juvenile hormone was assessed in females in all replicate selected and control lines at approximately 12 h or 4 days post-eclosion. There was no difference between selected and control lines in the specific activity of either class of enzymes that metabolize juvenile hormone.     

Pushing the limits of liver surgery for colorectal liver metastases:Current state and future directions

Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after surgery.Improvements in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover,changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field.     

Impregnation of bone chips with antibiotics and storage of antibiotics at different temperatures: an <Emphasis Type="Italic">in vitro</Emphasis> study

Background  

Allograft bone used in joint replacement surgery can additionally serve as a carrier for antibiotics and serve as a prophylaxis against infections. However, in vitro dose-response curves for bone chips impregnated with different kinds of antibiotics are not available. In addition, while it would be desirable to add the antibiotics to allograft bone chips before these are stored in a bone bank, the effects of different storage temperatures on antibiotics are unknown.     

Release of the lipid peroxidation marker 8-epi-prostaglandin F2 alpha from isolated gill pavement cells

The aim of the present study was to evaluate oxidative injury in gill pavement cells (GPCs) from fathead minnow (Pimephales promelas) using F2-isoprostane (F2-iP) release as an index of lipid peroxidation. Cells were isolated from pooled gill tissue by collagenase treatment, mechanical sieving, and Percoll density gradient centrifugation. Baseline levels of 8-epi-prostaglandin F2 alpha (8-epi-PGF2 alpha) were measured by incubating GPCs in physiological buffer (10(6) cells/ml) and enzyme immunoassay. After 60 min, the amount of immunoreactive 8-epi-PGF2 alpha (ir8-epi-PGF2 alpha) in control medium ranged from 1,374 to 5,515 pg/ml. Lead nitrate, 0.6 to 120 microM, did not influence ir8-epi-PGF2 alpha release, whereas FeCl3 stimulated release at 500 microM but not at 5 microM. Incubation medium was extracted for acidic lipids and analyzed by liquid chromatography/mass spectrometry/electrospray ionization. A compound in the medium exhibited a retention time on reverse-phase high-performance liquid chromatography nearly identical to that of synthetic 8-epi-PGF2 alpha The mass spectrum taken from the total ion chromatogram from 14.8 to 15.1 min contained a prominent ion at m/z 353, as expected for the molecular ion of 8-epi-PGF2 alpha. Similar results were obtained with tissue subjected to base hydrolysis. Mass spectra of extracted ion chromatograms obtained with gill extracts and authentic standard showed a close correspondence of fragment ions, providing definitive evidence for production and storage of F2-iPs by fish gills. In summary, F2-iP release occurs during lipid peroxidation injury to fish gill epithelium, and its measurement may facilitate aquatic toxicology studies of metallic and nonmetallic contaminants.