Tipifarnib as maintenance therapy did not improve disease-free survival in patients with acute myelogenous leukemia at high risk of relapse: Results of the phase III randomized E2902 trial.

PURPOSE: Despite the achievement of complete remission with chemotherapy in patients with acute myeloid leukemia (AML), relapse is common and the majority of patients will die of their disease. Patients who achieve a remission after refractory or relapsed disease as well as elderly patients have a very high rate of relapse even if they achieve a complete remission. A phase 3 randomized ECOG-ACRIN-led intergroup study was conducted to determine whether post-remission therapy with the farnesyl transferase inhibitor, tipifarnib (R115777), improved the disease-free survival (DFS) of adult patients with AML in complete remission (CR), at high risk for relapse. PATIENTS AND METHODS: Adult patients with AML in remission after salvage therapy and/or over age 60 in first remission were enrolled in this study. They were randomly assigned to treatment with tipifarnib or observation (control). The primary objective was to compare the disease-free survival (DFS) between the two arms based on intention to treat, which includes all randomized patients. RESULTS: One hundred and forty-four patients were enrolled on the study. Median DFS was 8.9 vs 5.3 months, for tipifarnib vs observation (one-sided p = 0.026) and did not cross the pre-specified boundary to call the study positive. For the 134 eligible patients, median DFS was 10.8 vs 5.3 months for those randomized to tipifarnib vs observation (one-sided p = 0.008). Moreover in an ad hoc evaluation of all women (n = 71) median DFS was 12.1 vs 3.9 months for tipifarnib vs observation (one-sided p = 0.0004) while median OS was 26.5 vs 8.4 months respectively (one-sided p = 0.001). CONCLUSION: This study was not able to demonstrate a benefit to tipifarnib as maintenance therapy in patients with AML in remission. While subsets of patients may indeed benefit, additional studies would be needed to elucidate that benefit which is unlikely given that other seemingly better options have since become available.

Transient changes in white matter microstructure during general anesthesia.

Cognitive dysfunction after surgery under general anesthesia is a well-recognized clinical phenomenon in the elderly. Physiological effects of various anesthetic agents have been studied at length. Very little is known about potential effects of anesthesia on brain structure. In this study we used Diffusion Tensor Imaging to compare the white matter microstructure of healthy control subjects under sevoflurane anesthesia with their awake state. Fractional Anisotropy, a white mater integrity index, transiently decreases throughout the brain during sevoflurane anesthesia and then returns back to baseline. Other DTI metrics such as mean diffusivity, axial diffusivity and radial diffusivity were increased under sevoflurane anesthesia. Although DTI metrics are age dependent, the transient changes due to sevoflurane were independent of age and sex. Volumetric analysis shows various white matter volumes decreased whereas some gray matter volumes increased during sevoflurane anesthesia. These results suggest that sevoflurane anesthesia has a significant, but transient, effect on white matter microstructure. In spite of the transient effects of sevoflurane anesthesia there were no measurable effects on brain white matter as determined by the DTI metrics at 2 days and 7 days following anesthesia. The role of white matter in the loss of consciousness under anesthesia will need to be studied and MRI studies with subjects under anesthesia will need to take these results into account.

Impact of baseline serum IL-8 on metastatic hormone-sensitive prostate cancer outcomes in the Phase 3 CHAARTED trial (E3805).

BACKGROUND: The immunosuppressive cytokine interleukin- 8 (IL-8), produced by tumor cells and some myeloid cells, promotes inflammation, angiogenesis, and metastasis. In our discovery work, elevated serum IL-8 at androgen deprivation therapy (ADT) initiation portended worse overall survival (OS). Leveraging serum samples from the phase 3 CHAARTED trial of patients treated with ADT +/- docetaxel for metastatic hormone-sensitive prostate cancer (mHSPC), we validated these findings. METHODS: Two hundred and thirty-three patients had serum samples drawn within 28 days of ADT initiation. The samples were assayed using the same Mesoscale Multiplex ELISA platform employed in the discovery cohort. After adjusting for performance status, disease volume, and de novo/metachronous metastases, multivariable Cox proportional hazards models assessed associations between IL-8 as continuous and binary variables on OS and time to castration-resistant prostate cancer (CRPC). The median IL-8 level (9.3 pg/ml) was the a priori binary cutpoint. Fixed-effects meta-analyses of the discovery and validation sets were performed. RESULTS: Higher IL-8 levels were prognostic for shorter OS (continuous: hazard ratio [HR] 2.2, 95% confidence interval [CI]: 1.4-3.6, p = .001; binary >9.3: HR 1.7, 95% CI: 1.2-2.4, p = .007) and time to CRPC (continuous: HR 2.3, 95% CI: 1.6-3.3, p < .001; binary: HR 1.8, 95% CI: 1.3-2.5, p < .001) and independent of docetaxel use, disease burden, and time of metastases. Meta-analysis including the discovery cohort, also showed that binary IL-8 levels >9.3 pg/ml from patients treated with ADT alone was prognostic for poorer OS (HR 1.8, 95% CI: 1.2-2.7, p = .007) and shorter time to CRPC (HR 1.4, 95% CI: 0.99-1.9, p = .057). CONCLUSIONS: In the phase 3 CHAARTED study of men with mHSPC at ADT initiation, elevated IL-8 portended worse survival and shorter time to castration-resistant prostate cancer independent of docetaxel administration, metastatic burden, and metachronous versus de novo metastatic presentation. These findings support targeting IL-8 as a strategy to improve mHSPC outcomes.

Social stress induces neurovascular pathology promoting depression.

Studies suggest that heightened peripheral inflammation contributes to the pathogenesis of major depressive disorder. We investigated the effect of chronic social defeat stress, a mouse model of depression, on blood-brain barrier (BBB) permeability and infiltration of peripheral immune signals. We found reduced expression of the endothelial cell tight junction protein claudin-5 (Cldn5) and abnormal blood vessel morphology in nucleus accumbens (NAc) of stress-susceptible but not resilient mice. CLDN5 expression was also decreased in NAc of depressed patients. Cldn5 downregulation was sufficient to induce depression-like behaviors following subthreshold social stress whereas chronic antidepressant treatment rescued Cldn5 loss and promoted resilience. Reduced BBB integrity in NAc of stress-susceptible or mice injected with adeno-associated virus expressing shRNA against Cldn5 caused infiltration of the peripheral cytokine interleukin-6 (IL-6) into brain parenchyma and subsequent expression of depression-like behaviors. These findings suggest that chronic social stress alters BBB integrity through loss of tight junction protein Cldn5, promoting peripheral IL-6 passage across the BBB and depression.