Phase I and pharmacokinetic study of veliparib,a PARP inhibitor,and pegylated liposomal doxorubicin (PLD) in recurrent gynecologic cancer and triple negative breast cancer with long-term follow-up

Poly(ADP-ribosyl) polymerases (PARPs) are nuclear enzymes with roles in DNA damage recognition and repair. PARP1 inhibition enhances the effects of DNA-damaging agents like doxorubicin. We sought to determine the recommended phase two dose (RP2D) of veliparib with pegylated liposomal doxorubicin (PLD) in breast and recurrent gynecologic cancer patients. Veliparib and PLD were administered in a standard phase 1, 3 + 3 dose-escalation design starting at 50 mg veliparib BID on days 1–14 with PLD 40 mg/mg2 on day 1 of a 28-day cycle. Dose escalation proceeded in two strata: A (prior PLD exposure) and B (no prior PLD exposure). Patients underwent limited pharmacokinetic (PK) sampling; an expansion PK cohort was added. 44 patients with recurrent ovarian or triple negative breast cancer were enrolled. Median age 56 years; 23 patients BRCA mutation carriers; median prior regimens four. Patients received a median of four cycles of veliparib/PLD. Grade 3/4 toxicities were observed in 10% of patients. Antitumor activity was observed in both sporadic and BRCA-deficient cancers. Two BRCA mutation carriers had complete responses. Two BRCA patients developed oral squamous cell cancers after completing this regimen. PLD exposure was observed to be higher when veliparib doses were > 200 mg BID. The RP2D is 200 mg veliparib BID on days 1–14 with 40 mg/m2 PLD on day 1 of a 28-day cycle. Anti-tumor activity was seen in both strata. However, given development of long-term squamous cell cancers and the PK interaction observed, efforts should focus on other targeted combinations to improve efficacy.     

Does Oil Rich in Alpha-Linolenic Fatty Acid Cause the Same Immune Modulation as Fish Oil in Walker 256 Tumor-Bearing Rats?

Objective: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. Methods: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. Results: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8⁺) subpopulation, and increased TNF-α production. Conclusions: Oil rich in ALA caused similar immune modulation in cancer when compared with FO.     

Rapid Increase in Neural Conduction Time in the Adult Human Auditory Brainstem Following Sudden Unilateral Deafness

Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis.