Hesperidin attenuates mitochondrial dysfunction during benzo(a)pyrene‐induced lung carcinogenesis in mice

The present study is designed to assess the mitochondrial status during benzo(a)pyrene (B(a)P)‐induced lung carcinogenesis in Swiss albino mice and to reveal the modulatory effect of hesperidin over it. B(a)P (50 mg/kg body weight)‐induced mitochondrial abnormalities was evident from alterations in mitochondrial lipid peroxides, antioxidant status (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione‐S‐transferase, reduced glutathione, vitamin E, and vitamin C), major tricarboxylic acid (TCA) cycle enzyme activities (isocitrate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, alpha‐ketoglutarate dehydrogenase), electron transport chain (ETC) complexes activities and ATP levels. Ultrastructural changes in lung mitochondria were also in accord with the above aberrations. Hesperidin (25 mg/kg body weight) supplementation effectively counteracted all the above changes and restored cellular normalcy, indicating its protective role during B(a)P‐induced lung cancer.     

Oncogenic microRNA‐27a is a target for anticancer agent methyl 2‐cyano‐3,11‐dioxo‐18β‐olean‐1,12‐dien‐30‐oate in colon cancer cells

Methyl 2‐cyano‐3,11‐dioxo‐18β‐olean‐1,12‐dien‐30‐oate (CDODA‐Me) is a synthetic derivative of glycyrrhetinic acid, a triterpenoid phytochemical found in licorice extracts. CDODA‐Me inhibited growth of RKO and SW480 colon cancer cells and this was accompanied by decreased expression of Sp1, Sp3 and Sp4 protein and mRNA and several Sp‐dependent genes including survivin, vascular endothelial growth factor (VEGF), and VEGF receptor 1 (VEGFR1 or Flt‐1). CDODA‐Me also induced apoptosis, arrested RKO and SW480 cells at G₂/M, and inhibited tumor growth in athymic nude mice bearing RKO cells as xenografts. CDODA‐Me decreased expression of microRNA‐27a (miR‐27a), and this was accompanied by increased expression of 2 miR‐27a‐regulated mRNAs, namely ZBTB10 (an Sp repressor) and Myt‐1 which catalyzes phosphorylation of cdc2 to inhibit progression of cells through G₂/M. Both CDODA‐Me and antisense miR‐27a induced comparable responses in RKO and SW480 cells, suggesting that the potent anticarcinogenic activity of CDODA‐Me is due to repression of oncogenic miR‐27a. © 2009 UICC     

Sorbitol Crystallization Can Lead to Protein Aggregation in Frozen Protein Formulations

Purpose This work examines the cause of aggregation of an Fc-fusion protein formulated in sorbitol upon frozen storage for extended periods of time at −30°C.Materials and Methods We designed sub-ambient differential scanning calorimetry (DSC) experiments to capture the effects of long-term frozen storage. The physical stability of formulation samples was monitored by size exclusion high performance liquid chromatography (SE-HPLC).Results DSC analysis of non-frozen samples shows the expected glass transitions (T_g′) at −45°C for samples in sorbitol and at −32°C in sucrose. In time course studies where sorbitol formulations were stored at −30°C and analyzed by DSC without thawing, two endothermic transitions were observed: a melting endotherm at −20°C dissipated over time, and a second endotherm at −8°C was seen after approximately 2 weeks and persisted in all later time points. Protein aggregation was only seen in the samples formulated in sorbitol and stored at −30°C, correlating aggregation with the aforementioned melts.Conclusions The observed melts are characteristic of crystalline substances and suggest that the sorbitol crystallizes over time. During freezing, the excipient must remain in the same phase as the protein to ensure protein stability. By crystallizing, the sorbitol is phase-separated from the protein, which leads to protein aggregation.     

Deep sclerectomy-trabeculectomy with mitomycin C in treating glaucoma: postoperative long-term results

AIM: To determine the long-term postoperative outcomes of deep sclerectomy-trabeculectomy (DST) with mitomycin C (MMC) in the treatment of glaucoma. METHODS: Patients who underwent DST with MMC between 2010 and 2017 were included in this retrospective observational study. Complete success was defined as postoperative intraocular pressure (IOP) ≤21 mm Hg or 30% reduction of IOP from baseline without any topical IOP-lowering agent, and qualified success defined as IOP≤21 mm Hg or 30% reduction of IOP from baseline with/without single topical agent. We evaluated the surgical success rates and complication rates of this procedure, as well as described the IOP profiles, best corrected visual acuity (BCVA) profiles and mean deviations (MD) of Humphrey visual field (HVF) 24-2 performance at each follow-up time point. Mixed linear regression models were constructed to determine estimated predictive values of demographic data, use of topical IOP-lowering agents, baseline and postoperative IOP and optical profiles (e.g., BCVA and MD). RESULTS: Totally 98 eyes (mean postoperative follow-up 67.5mo) showed mean IOP reduction at every follow-up interval. Both median BCVA and MD of visual fields were maintained throughout the follow-up intervals when comparing to baseline. The number of IOP-lowering medications decreased from 2.8±0.8 to 0.3±0.7 (P=0.068). Totally 84 (85.7%) eyes achieved complete success at final follow-up. Transient hyphaema and transient choroidal effusion developed in 15 eyes (15.3%) and 11 eyes (11.2%) respectively. Other complications included shallow anterior chamber in 5 eyes (5.1%), bleb leak in 4 eyes (4.1%), bleb revision in 7 eyes (7.1%), bleb needling in 9 eyes (9.2%) and repeat trabeculectomy in 1 eye (1.0%). There was no endophthalmitis, blebitis or macular oedema. There was no significant correlation between postoperative IOP control and postoperative BCVA. CONCLUSION: DST with MMC demonstrates effective and sustained long-term outcomes in the treatment of glaucoma with no major complication.     

Characterization of Gene Therapy Associated Uveitis Following Intravitreal Adeno-Associated Virus Injection in Mice

PurposeTo characterize the intraocular immune cell infiltrate induced by intravitreal adeno-associated virus (AAV) gene therapy.MethodsAAV vectors carrying plasmids expressing green fluorescent protein under the control of PR2.1 were injected intravitreally into AAV naive and AAV primed C57Bl/6 mice. Clinical inflammation was assessed using optical coherence tomography. Intraocular immune cell populations were identified and quantified by flow cytometry on days 1, 7, and 29 after intravitreal injection and compared with sham and fellow eye controls.ResultsOptical coherence tomography inflammation score and total CD45+ cell number were significantly higher in AAV injected eyes compared to uninjected fellow eye and sham injected controls. Clinically apparent inflammation (vitritis on optical coherence tomography) and cellular inflammation (CD45+ cell number) was significantly increased in AAV injected eyes and peaked around day 7. Vitritis resolved by day 29, but cellular inflammation persisted through day 29. On day 1, neutrophils and activated monocytes were the dominant cell populations in all AAV injected eyes. On day 7, eyes of AAV exposed animals had significantly more dendritic cells and T cells than eyes of AAV naive animals. By day 29, CD8– T cells were the dominant CD45+ cell population in AAV injected eyes.ConclusionsIntravitreal AAV injection in mice generates clinically evident inflammation that is mild and seems to resolve spontaneously. However, the total number of intraocular CD45+ cells, particularly T cells, remain elevated. Both innate and adaptive immune cells respond to intravitreal AAV regardless of prior immune status, but the adaptive response is delayed in AAV naive eyes.     

Kearns Sayre syndrome: an atypical presentation

Kearns Sayre syndrome is a rare presentation which usually involves a triad of factors: external ophthalmoplegia, retinal pigmentary degeneration, and heart block. We present a clinically and histopathologically confirmed case of Kearns Sayre syndrome that involved no retinal pathology.     

Cancer-associated stromal fibroblasts promote pancreatic tumor progression

Pancreatic adenocarcinoma is characterized by a dense background of tumor associated stroma originating from abundant pancreatic stellate cells. The aim of this study was to determine the effect of human pancreatic stellate cells (HPSC) on pancreatic tumor progression. HPSCs were isolated from resected pancreatic adenocarcinoma samples and immortalized with telomerase and SV40 large T antigen. Effects of HPSC conditioned medium (HPSC-CM) on in vitro proliferation, migration, invasion, soft-agar colony formation, and survival in the presence of gemcitabine or radiation therapy were measured in two pancreatic cancer cell lines. The effects of HPSCs on tumors were examined in an orthotopic murine model of pancreatic cancer by co-injecting them with cancer cells and analyzing growth and metastasis. HPSC-CM dose-dependently increased BxPC3 and Panc1 tumor cell proliferation, migration, invasion, and colony formation. Furthermore, gemcitabine and radiation therapy were less effective in tumor cells treated with HPSC-CM. HPSC-CM activated the mitogen-activated protein kinase and Akt pathways in tumor cells. Co-injection of tumor cells with HPSCs in an orthotopic model resulted in increased primary tumor incidence, size, and metastasis, which corresponded with the proportion of HPSCs. HPSCs produce soluble factors that stimulate signaling pathways related to proliferation and survival of pancreatic cancer cells, and the presence of HPSCs in tumors increases the growth and metastasis of these cells. These data indicate that stellate cells have an important role in supporting and promoting pancreatic cancer. Identification of HPSC-derived factors may lead to novel stroma-targeted therapies for pancreatic cancer.     

Disulfiram (DSF) acts as a copper ionophore to induce copper‐dependent oxidative stress and mediate anti‐tumor efficacy in inflammatory breast cancer

Cancer cells often have increased levels of reactive oxygen species (ROS); however, acquisition of redox adaptive mechanisms allows for evasion of ROS‐mediated death. Inflammatory breast cancer (IBC) is a distinct, advanced BC subtype characterized by high rates of residual disease and recurrence despite advances in multimodality treatment. Using a cellular model of IBC, we identified an oxidative stress response (OSR) signature in surviving IBC cells after administration of an acute dose of an ROS inducer. Metagene analysis of patient samples revealed significantly higher OSR scores in IBC tumor samples compared to normal or non‐IBC tissues, which may contribute to the poor response of IBC tumors to common treatment strategies, which often rely heavily on ROS induction. To combat this adaptation, we utilized a potent redox modulator, the FDA‐approved small molecule Disulfiram (DSF), alone and in combination with copper. DSF forms a complex with copper (DSF‐Cu) increasing intracellular copper concentration both in vitro and in vivo, bypassing the need for membrane transporters. DSF‐Cu antagonized NFκB signaling, aldehyde dehydrogenase activity and antioxidant levels, inducing oxidative stress‐mediated apoptosis in multiple IBC cellular models. In vivo, DSF‐Cu significantly inhibited tumor growth without significant toxicity, causing apoptosis only in tumor cells. These results indicate that IBC tumors are highly redox adapted, which may render them resistant to ROS‐inducing therapies. DSF, through redox modulation, may be a useful approach to enhance chemo‐ and/or radio‐sensitivity for advanced BC subtypes where therapeutic resistance is an impediment to durable responses to current standard of care.