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Background:Melphalan is one of the most active chemotherapeutic agents in the treatment of multiple myeloma (MM). However, the mechanism underlying differential patient responses to melphalan therapy is unknown.Methods:Chromatin structure, transcriptional activity and DNA damage response signals were examined following ex vivo treatment with melphalan of both malignant bone marrow plasma cells (BMPCs) and peripheral blood mononuclear cells (PBMCs) of MM patients, responders (n=57) or non-responders (n=28) to melphalan therapy. PBMCs from healthy controls (n=25) were also included in the study.Results:In both BMPCs and PBMCs, the local chromatin looseness, transcriptional activity and repair efficiency of the transcribed strand (TS) were significantly higher in non-responders than in responders and lowest in healthy controls (all P<0.05). Moreover, we found that melphalan-induced apoptosis inversely correlated with the repair efficiency of the TS, with the duration of the inhibition of mRNA synthesis, phosphorylation of p53 at serine 15 and apoptosis rates being higher in responders than in non-responders (all P<0.001).Conclusions:Our findings provide a mechanistic basis for the link between DNA repair efficiency and response to melphalan therapy. Interestingly, the observation of these phenomena in PBMCs provides a novel approach for the prediction of response to anti-myeloma therapy. [ABSTRACT FROM AUTHOR]

Background: In the open-label randomized phase III AURELIA trial, adding bevacizumab to chemotherapy for platinumresistant ovarian cancer (PROC) significantly improved progression-free survival and response rate versus chemotherapy alone, but not overall survival (OS). We explored the effect of bevacizumab use after disease progression (PD) in patients randomized to chemotherapy alone. Patients and methods: In AURELIA, 361 women with PROC were randomized to chemotherapy alone or with bevacizumab. Patients initially randomized to chemotherapy were offered bevacizumab after PD. Post hoc analyses assessed efficacy and safety in three subgroups: chemotherapy alone, chemotherapy followed by bevacizumab after PD, and chemotherapy plus bevacizumab at randomization. Results: Of the 182 patients randomized to chemotherapy alone, 72 (40%) received bevacizumab after PD and 110 (60%) never received bevacizumab. There were no significant differences in patient and disease characteristics between these subgroups at baseline or the time of PD. Compared with patients never receiving bevacizumab, the risk of death was significantly reduced in patients receiving bevacizumab either upfront with chemotherapy [hazard ratio (HR)=0.68, 95% confidence interval (CI) 0.52-0.90] or after PD (HR=0.60, 95% CI 0.43-0.86). The tolerability of bevacizumab was similar with administration upfront or after PD. Conclusions: Post-PD bevacizumab use may have confounded OS results in AURELIA. In these exploratory analyses of nonrandomized subgroups, bevacizumab use, either with chemotherapy or after PD on chemotherapy alone, improved OS compared with no bevacizumab. Combining bevacizumab with chemotherapy at first appearance of platinum resistance maximises the likelihood of patients receiving this active treatment for PROC. ClinicalTrials.gov: NCT00976911. [ABSTRACT FROM AUTHOR]