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Background: Trastuzumab is a humanized monoclonal antibody that targets site-specifically human epidermal growth factor-2 receptor (HER2) cell surface antigen overexpressed in approximately 20% of human breast carcinomas. Despite its positive therapeutic outcomes, a large proportion of individuals are unresponsive to the treatment with the trastuzumab or develop resistance to it., Objective: To evaluate a chemically synthesized trastuzumab-based antibody-drug conjugate (ADC) to improve the trastuzumab therapeutic index., Methods: The current study explored the physiochemical characteristics of the trastuzumab conjugated to a cytotoxic chemotherapy agent DM1 via Succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) linker, created in our earlier study, using SDS-PAGE, UV/VIS, and RP-HPLC analyses. The antitumor effects of the ADCs were analyzed using MDA-MB-231 (HER2-negative) and SK-BR-3 (HER2-positive) cell lines utilizing in vitro cytotoxicity, viability, and binding assays. Three different formats of a HER2-targeting agent: trastuzumab, synthesized trastuzumab-MCC-DM1, and commercially available drug T-DM1 (Kadcyla®) were compared., Results: UV-VIS spectroscopic analysis showed that the trastuzumab-MCC-DM1 conjugates, on average, entailed 2.9 DM1 payloads per trastuzumab. A free drug level of 2.5% was determined by RP-HPLC. The conjugate appeared as two bands on a reducing SDS-PAGE gel. MTT viability assay showed that conjugating trastuzumab with DM1 significantly improved the antiproliferative effects of this antibody in vitro. Importantly, the evaluations using LDH release and cell apoptosis assays confirmed that trastuzumab maintains its ability to induce cell death response while conjugating with the DM1. The binding efficiency of trastuzumab-MCC-DM1 was comparable to that of the naked trastuzumab., Conclusion: Trastuzumab-MCC-DM1 was found effective against HER2+ tumors. The potency of this synthesized conjugate brings it closer to the commercially available T-DM1.

Recent studies have proven several promising anticancer activities for cold atmospheric plasma (CAP) against a wide range of cancer cells in vitro. Recently, media treated with CAP have also found to effectively eradicate cancer cells similar to the CAP. Based on advantages, many researchers prefer to apply CAP-activated media (PAM) as an alternative to cap in the treatment of cancer. However, less has been achieved regarding the anticancer effects and anticancer mechanisms of PAM. Investigating the selective anticancerous activities of PAM, the viability of SKBR3, MCF7, ASPC-1, A-549, G-292, and SW742 cancer cell lines, as well as normal human skin fibroblasts (FMGB-1) and MCF10A cells in relation to the media activation time, and the length of exposure was studied. Also, we examined the concentration of ozone in media as a function to CAP activation time since recent studies have proposed ozone as a pivotal reactive species in the induction of cell death. Based on the result, both increasing the duration of media activation time and the length of exposure to PAM could significantly increase the anticancer activity. Nevertheless, the cytotoxicity on normal cells was either not affected or slightly increased. Among the six tested cancer cell lines, SW742 was the most resistant and SKBR3 the most susceptible cancer cell lines to PAM. Also, increasing duration of treatment with CAP resulted in a significant rise in O 3 concentration levels in media. Overall, these results suggest PAM, as a promising tool in the treatment of different cancers and O 3 formation as a probable underlying mechanism., (© 2018 Wiley Periodicals, Inc.)

Mentioned in Blinatumomab (Blincyto®) clinical safety report, a 5 year old boy with acute lymphoblastic leukemia (ALL) receiving Blincyto® with the concentration of 30μg/m 2 /day on the fourth day of therapy developed both Cytokine Release Syndrome (CRS) and Tumor Lysis Syndrome (TLS). Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and Bilirubin peaks were 18, 7 and 8 folds more than upper normal limit (UNL) respectively. However, albumin was reduced to approximately half of the lower Normal limit (LNL). Although Blincyto® administration was immediately withdrawn, he expired in the day 10 due to a fatal cardiac failure. Based on evidence, FDA concluded that CRS was the main cause of death in this patient. Evoking evidence now propose that aberrant pro-inflammatory cytokines secretion, the hallmark of CRS, and subsequent elevation in nitric oxide (NO) can result in both inotropic and chronotropic alterations in myocardial excitation-contraction coupling, myocardial contractility suppression, desensitization of β-adrenergic receptors stimulation, development of acute cardiac failure and death. The probably neglecting point here is that TLS itself can also develop life threatening conditions including sudden cardiac failure through induction of hypocalcemia, hyperkalemia and hyperuricemia, making CRS monitoring and proper required supportive interventions more complex. Here, first we enumerate probable mechanisms through which CRS results in development of fatal cardiac failure and then explain the possible neglected role of TLS in development of the fatal cardiac failure., (Copyright © 2016. Published by Elsevier B.V.)