Deferasirox Might Induce Immunosuppression Comparable to Deferoxamine.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3755-3755
Author(s):  
Dae-Chul Jeong ◽  
Nack-Gyun Chung ◽  
Bin Cho ◽  
Sung-Yong Kim ◽  
Chi Wha Han ◽  
...  

Abstract Background: The iron chelating agents (ICA) have various biological effects besides iron chelation, including induction of apoptosis and immune modulation. Deferoxamine (DFO) is known to have some immunosuppressive effects. Deferasirox (DFS) is a new oral iron chelating agent, and its biologic effects are not known clearly. We investigated the immunosuppressive effects of DFS in comparison with DFO. Materials and Methods: We obtained spleen cells (SP) from 5 week-old female C57BL/6 (B6, H-2b) and BLAB/c (H-2d). The cytotoxicity of ICA at various concentrations was examined by CCK8 method for 48 hours. The cell proliferation assay (CPA) was done with B6 SP and irradiated BALB/c SP under various concentrations of DFO or DFS with phytohemaglutinin by ELISA method (n = 6). Stimulation index (SI) was defined as the ratio of experimental OD compared with OD of control. Experimental design was as follows: control (without any treatment), DFO 5, 10, 50, 100 μM, and DFS 15, 30, 50, 100 μM. Also, CPA was performed after 12 hours incubation with 20 μM ferric chloride (FE) (n = 6). For cytokine analysis, IL-2, IL-10, and TGF-β were measured from supernatants collected during CPA. Results: There was over 100% viability after 48 hours of incubation at various concentrations, and similarly under FE. In DFO group, there was inhibition of cell proliferation at all concentrations with or without FE. Inhibition was greater at DFO10 and DFO50 than others with treatment of FE (P < 0.01). In DFS group, SI without FE diminished regardless of concentration. SI with FE showed significant decrease at DFS levels higher than 30mM (P < 0.01). Decrement of SI in DFS group was comparable to that in DFO group. TGF-b and IL-10 levels were not significant at any concentration of both ICAs (P > 0.05). However, IL-10 was diminished according to DFS or DFO concentration without statistical significance (P > 0.05). In DFS group, the level of IL-2 was higher at 30 μM than others (P < 0.01). In DFO group, IL-2 level did not change according to concentration. Conclusion: These data suggest that ICAs may have immune suppressive effects which may not be dependent on cytokines. We conclude that DFS, a new oral iron chelating agent, induce immunosuppression comparable to DFO.

2019 ◽  
Vol 19 (10) ◽  
pp. 817-827
Author(s):  
Jianbo Zhu ◽  
Lijuan Deng ◽  
Baozhen Chen ◽  
Wenqing Huang ◽  
Xiandong Lin ◽  
...  

Background:Recurrence is the leading cause of treatment failure and death in patients with gastric cancer (GC). However, the mechanism underlying GC recurrence remains unclear, and prognostic markers are still lacking.Methods:We analyzed DNA methylation profiles in gastric cancer cases with shorter survival (<1 year) or longer survival (> 3 years), and identified candidate genes associated with GC recurrence. Then, the biological effects of these genes on gastric cancer were studied.Results:A novel gene, magnesium-dependent phosphatase 1 (mdp1), was identified as a candidate gene whose DNA methylation was higher in GC samples from patients with shorter survival and lower in patients with longer survival. MDP1 protein was highly expressed in GC tissues with longer survival time, and also had a tendency to be expressed in highly differentiated GC samples. Forced expression of MDP1 in GC cell line BGC-823 inhibited cell proliferation, whereas the knockdown of MDP1 protein promoted cell growth. Overexpression of MDP1 in BGC-823 cells also enhanced cell senescence and apoptosis. Cytoplasmic kinase protein c-Jun N-terminal kinase (JNK) and signal transducer and activator of transcription 3 (Stat3) were found to mediate the biological function of MDP1.Conclusion:These results suggest that MDP1 protein suppresses the survival of gastric cancer cells and loss of MDP expression may benefit the recurrence of gastric cancer.


2019 ◽  
Vol 15 (2) ◽  
pp. 131-145
Author(s):  
Gajanan V. Sherbet

The mevalonate pathway (also known as the cholesterol biosynthesis pathway) plays a crucial metabolic role in normal cell function as well as in the pathological environment. It leads to the synthesis of sterol and non-sterol isoprenoid biomolecules which subserve a variety of cellular functions. It is known to be deregulated in many disease processes. Statins and bisphosphonates are prominent inhibitors of the mevalonate pathway. They inhibit cell proliferation and activate apoptotic signalling and suppress tumour growth. Statins subdue metastatic spread of tumours by virtue of their ability to suppress invasion and angiogenesis. The induction of autophagy is another feature of statin effects that could contribute to the suppression of metastasis. Herein highlighted are the major signalling systems that statins engage to generate these biological effects. Statins can constrain tumour growth by influencing the expression and function of growth factor and receptor systems. They may suppress epithelial mesenchymal transition with resultant inhibition of cell survival signalling, together with the inhibition of cancer stem cell generation, and their maintenance and expansion. They can suppress ER (oestrogen receptor)-α in breast cancer cells. Statins have been implicated in the activation of the serine/threonine protein kinase AMPK (5&#039; adenosine monophosphate-activated protein) leading to the suppression of cell proliferation. Both statins and bisphosphonates can suppress angiogenic signalling by HIF (hypoxia- inducible factor)-1/eNOS (endothelial nitric oxide synthase) and VEGF (vascular endothelial growth factor)/VEGFR (VEGF receptor). Statins have been linked with improvements in disease prognosis. Also attributed to them is the ability of cancer prevention and reduction of risk of some forms of cancer. The wide spectrum of cancer associated events which these mevalonate inhibitors appear to influence would suggest a conceivable role for them in cancer management. However, much deliberation is warranted in the design and planning of clinical trials, their scope and definition of endpoints, modes risk assessment and the accrual of benefits.


RSC Advances ◽  
2021 ◽  
Vol 11 (20) ◽  
pp. 12086-12094
Author(s):  
Tielong Li ◽  
Jiaxin Wen ◽  
Bingjie Li ◽  
Shihu Ding ◽  
Wei Wang

To explore the application of mineral in bioremediation of contaminated aquifers, this study investigated tourmaline-induced changes in TCE degradation, community structure, cell proliferation and gene expression of dechlorinating bacteria.


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Xiaoguang Gu ◽  
Jianan Zhang ◽  
Yajuan Ran ◽  
Hena Pan ◽  
JinHong Jia ◽  
...  

AbstractCircular RNAs have been reported to play significant roles in regulating pathophysiological processes while also guiding clinical diagnosis and treatment of hepatocellular carcinoma (HCC). However, only a few circRNAs have been identified thus far. Herein, we investigated the role of a specific closed-loop structure of hsa_circ_101555 that was generated by back-splicing of the host gene casein kinase 1 gamma 1 (CSNK1G1) in the development and proliferation of HCC. We investigated the expression of Hsa_circ_101555 in HCC and normal tissues using bioinformatics. The expression level of hsa_circ_101555 was further detected by fluorescence in situ hybridization and qRT-PCR in ten HCC patients. Transwell, migration, WST-1 assays, and colony formation assays were used to evaluate the role of hsa_circ_101555 in HCC development and proliferation. The regulatory mechanisms of hsa_circ_101555 in miR-145-5p and CDCA3 were determined by dual luciferase reporter assay. A mouse xenograft model was also used to determine the effect of hsa_circ_101555 on HCC growth in vivo. hsa_circ_101555 showed greater stability than the linear RNA; while in vitro and in vivo results demonstrated that hsa_circ_101555 silencing significantly suppressed cell proliferation, migration, and invasion of HCC cells. Rescue experiments further demonstrated that suppression of miR-145-5p significantly attenuated the biological effects of hsa_circ_101555 knockdown in HCC cells. We also identified a putative oncogene CDCA3 as a potential miR-145-5p target. Thus, our results demonstrated that hsa_circ_101555 might function as a competing endogenous RNA of miR-145-5p to upregulate CDCA3 expression in HCC. These findings suggest that hsa_circ_101555 may be a potential therapeutic target for patients with HCC.


Author(s):  
Jin-Chun Qi ◽  
Zhan Yang ◽  
Tao Lin ◽  
Long Ma ◽  
Ya-Xuan Wang ◽  
...  

Abstract Background Both E2F transcription factor and cyclin-dependent kinases (CDKs), which increase or decrease E2F activity by phosphorylating E2F or its partner, are involved in the control of cell proliferation, and some circRNAs and miRNAs regulate the expression of E2F and CDKs. However, little is known about whether dysregulation among E2Fs, CDKs, circRNAs and miRNAs occurs in human PCa. Methods The expression levels of CDK13 in PCa tissues and different cell lines were determined by quantitative real-time PCR and Western blot analysis. In vitro and in vivo assays were preformed to explore the biological effects of CDK13 in PCa cells. Co-immunoprecipitation anlysis coupled with mass spectrometry was used to identify E2F5 interaction with CDK13. A CRISPR-Cas9 complex was used to activate endogenous CDK13 and circCDK13 expression. Furthermore, the mechanism of circCDK13 was investigated by using loss-of-function and gain-of-function assays in vitro and in vivo. Results Here we show that CDK13 is significantly upregulated in human PCa tissues. CDK13 depletion and overexpression in PCa cells decrease and increase, respectively, cell proliferation, and the pro-proliferation effect of CDK13 is strengthened by its interaction with E2F5. Mechanistically, transcriptional activation of endogenous CDK13, but not the forced expression of CDK13 by its expression vector, remarkably promotes E2F5 protein expression by facilitating circCDK13 formation. Further, the upregulation of E2F5 enhances CDK13 transcription and promotes circCDK13 biogenesis, which in turn sponges miR-212-5p/449a and thus relieves their repression of the E2F5 expression, subsequently leading to the upregulation of E2F5 expression and PCa cell proliferation. Conclusions These findings suggest that CDK13 upregulation-induced formation of the positive feedback loop among circCDK13, miR-212-5p/miR-449a and E2F5 is responsible for PCa development. Targeting this newly identified regulatory axis may provide therapeutic benefit against PCa progression and drug resistance.


Author(s):  
Samar M. Shehata ◽  
Mohamed I. Amin ◽  
El Sayed H. Zidan

Abstract Background Iron deposition distorts the local magnetic field exerting T2* signal decay. Biopsy, serum ferritin, echocardiography are not reliable to adjust iron chelation therapy. Quantified MRI signal decay can replace biopsy to diagnose iron burden, guide treatment, and follow up. The objective of this study is to evaluate the role of T2* in quantification of the liver and heart iron burden in thalassemia major patients. This cross-sectional study included 44 thalassemia patients who were referred to MRI unit, underwent T2* MRI. Results Twenty-one male (47.7%) and 23 female (52.3%) were included (age range 6–15 years, mean age 10.9 ± 2.9 years). Patients with excess hepatic iron show the following: 11/40 (27.5%) mild, (13/40) 32.5% moderate, and (14/40) 35% severe liver iron overload. High statistical significance regarding association between LIC and liver T2* (p = 0.000) encountered. Cardiac T2* values showed no relationship with age (p = 0.6). Conclusion T2* is a good method to quantify, monitor hepatic and myocardial iron burden, guiding chelation therapy and prevent iron-induced cardiac complications.


2022 ◽  
Vol 351 ◽  
pp. 109768
Author(s):  
Mahshid Mohammadi ◽  
Leila Bagheri ◽  
Amr Badreldin ◽  
Pedram Fatehi ◽  
Leila Pakzad ◽  
...  

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. TPS4153-TPS4153
Author(s):  
Tae Yong Kim ◽  
Jee Sun Yoon ◽  
Ah-Rong Nam ◽  
Ju-Hee Bang ◽  
Kyoung Seok Oh ◽  
...  

TPS4153 Background: Olaparib (PARP inhibitor) leads to DNA damage and cell death. In phase III study (GOLD), olaparib plus paclitaxel did not improve overall survival (OS) compared with paclitaxel in second-line gastric cancer (GC) patients with statistical significance, even though there was absolute increase of OS (Lancet Oncol 2017). This highlights the importance of biomarker-based patient selection. The changes of tumor microenvironment by paclitaxel/olaparib have not been explored. Besides DNA damage, olaparib induces positive or negative immune modulation by recruiting T cells, promoting type I interferon and upregulating PD-L1, which suggests anti-PD (L1) inhibitor plus olaparib could enhance anti-tumor immunity. Combination of Anti-PD-1 agents with chemotherapy showed a good clinical efficacy in first-line of GC compared with chemotherapy alone (Checkmate 649). Based on these findings, the combination of paclitaxel/olaparib/anti-PD(L1)1 inhibitor, with different mode of actions, might enhance antitumor activity. This is phase II study of paclitaxel/olaparib/durvalumab combination in second-line GC patients, to find out immune modulation effects by paclitaxel/olaparib combination, and to see the efficacy, safety, optimal biomarkers for this combination. Methods: All patients with histologically confirmed unresectable GC have failed to prior one chemotherapy and measurable lesion. Prior exposure to anti-PD(L1)1, PARP inhibitor is excluded. At 1st cycle, paclitaxel (80 mg/m2) on D1, 8 and 15 and olaparib (150 mg bid) on D1-28 is administered. Pre-treatment biopsy and after first cycle biopsy is done. From second cycle, durvalumab 1500 mg on D1 every 4 weeks is added. At the time of disease progression, tumor biopsy is mandatory. Blood samples for biomarkers should be obtained every cycles. Response evaluation is performed after first 3 cycles and repeated every 2 cycles. Primary endpoint is the disease control rate (the percentage of patients who have achieved complete or partial remission, stable disease based on RECIST v1). Key secondary endpoints are overall response rate, progression-free survival, OS, quality of life and safety. Clinical trial information: NCT03579784.


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