Effect of mannitol on acute kidney injury induced by cisplatin.

PURPOSE: Acute kidney injury (AKI) is a frequent dose-limiting toxicity induced by cisplatin. Mannitol has been used in hydration protocols to mitigate this adverse event but its role remains controversial. The aim of this study is to define the impact of mannitol on AKI in patients receiving cisplatin. METHODS: This retrospective observational study was conducted in cancer patients who received at least one dose of cisplatin between September 2010 and December 2016 at the Centre hospitalier de l'Université de Montréal. The primary outcome of this study was the comparison of all grade cisplatin-associated AKI between hydration protocols with or without mannitol. RESULTS: A total of 1821 patients were included of which 658 received mannitol whilst 1163 received hydration alone. The risk of all grade cisplatin-associated AKI was significantly lower for the mannitol group (Hazard Ratio (HR) = 0.62; 95% CI [0.42, 0.89]). This result was mainly driven by gynecologic (HR = 0.50), upper gastrointestinal (HR = 0.32), urinary tract malignancies (HR = 0.29) and lymphoma (HR = 0.33). No significant difference was seen for head and neck (HN), lung, germ cells and other cancers. However, HN cancers patients receiving mannitol had fewer grade 2 and 3 AKI. Significantly fewer AKI events were observed in HN, lung, upper gastrointestinal and urinary tract cancer when mannitol was added for cisplatin dose <75 mg/m2. CONCLUSION: Although the results were generally driven by a decrease of grade 1 AKI for most cancers, the greatest benefit of mannitol was seen with cisplatin doses lower than 75 mg/m2 and should probably be reinstated in this setting.

Durable complete remission following anti-EGFR antibodies in recurrent metastatic colorectal cancer.

In this case report, we describe a patient who remains in complete remission two years after the discontinuation of anti-EGFR monotherapy as a third-line treatment, accompanied by persistent severe hypomagnesemia. A 45-year-old Caucasian woman with mCRC started chemotherapy with weekly cetuximab. After ten months of treatment, the therapy was stopped because the patient had persistent grade III hypomagnesemia despite amiloride, oral, and intravenous magnesium. A month later, the patient was switched to panitumumab 6 mg/kg every two weeks for four additional months to avoid weekly visits to the clinic. Following discontinuation of panitumumab, PET scans remain negative to this day, two years after anti-EGFR therapy discontinuation. No factor has been identified to explain the complete and sustained response experienced by this patient. Hypomagnesemia is a common adverse effect of anti-EGFR therapy that can lead to treatment interruption and discontinuation if severe. This case highlights the importance of pursuing anti-EGFR therapy when a response is observed in spite of severe hypomagnesemia. It also provides preliminary information that anti-EGFR therapy could be stopped after a complete response is obtained.

A Conserved Target Site in HIV-1 Gag RNA is Accessible to Inhibition by Both an HDV Ribozyme and a Short Hairpin RNA.

Antisense-based molecules targeting HIV-1 RNA have the potential to be used as part of gene or drug therapy to treat HIV-1 infection. In this study, HIV-1 RNA was screened to identify more conserved and accessible target sites for ribozymes based on the hepatitis delta virus motif. Using a quantitative screen for effects on HIV-1 production, we identified a ribozyme targeting a highly conserved site in the Gag coding sequence with improved inhibitory potential compared to our previously described candidates targeting the overlapping Tat/Rev coding sequence. We also demonstrate that this target site is highly accessible to short hairpin directed RNA interference, suggesting that it may be available for the binding of antisense RNAs with different modes of action. We provide evidence that this target site is structurally conserved in diverse viral strains and that it is sufficiently different from the human transcriptome to limit off-target effects from antisense therapies. We also show that the modified hepatitis delta virus ribozyme is more sensitive to a mismatch in its target site compared to the short hairpin RNA. Overall, our results validate the potential of a new target site in HIV-1 RNA to be used for the development of antisense therapies.