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Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1520-1520
Author(s):  
Theodoros Karantanos ◽  
Hua-Ling Tsai ◽  
Mark Levis ◽  
Ravi Varadhan ◽  
Richard J. Jones ◽  
...  

Abstract INTRODUCTION: The management of myelodysplastic syndrome/myeloproliferative overlap neoplasms (MDS/MPN) remains challenging due to their molecular complexity. Hypo-methylating agents (HMA) have been used for cytoreduction and preparation of patients for allogeneic blood or marrow transplantation (BMT). However, less than 50% patients have a meaningful response to HMA and predictive factors for response remain unknown. The aim of our study is to examine molecular predictors of response to HMA in patients with MDS/MPN. PATIENTS AND METHODS: We performed a retrospective analysis of 150 patients evaluated at our center for chronic myelomonocytic leukemia (CMML), atypical chronic myeloid leukemia (aCML) and unclassifiable MDS/MPN (MDS/MPN-U) between 1/1/2010 and 12/31/2020. Forty-three individuals who were treated with HMA during chronic phase and had next generation sequencing (NGS) using the established 63-genes panel were identified. Complete and partial remission (CR and PR), and marrow response (MR) were assessed based on the MDS/MPN International Working Group response criteria. Univariate logistic regression analysis was used to associate the number of somatic mutations or high-risk (HR) mutations (NRAS, SETBP1, RUNX1, EZH2, TP53, ASXL1, STAG2), and other disease specific factors at the time of the initiation of HMA with response categories. Multivariable analysis for modeling response were conducted via Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression approach, where the predictors were selected based on 5-fold cross validation with turning parameter selected to minimize deviance of logistic regression model. Kaplan-Meier was used to assess the overall survival based on the CR/PR status at 6 months from the initiation of HMA in landmark analysis. Cox-regression analysis considering the occurrence of CR/PR as a time-varying covariate was used to assess the impact of CR/PR on overall survival. RESULTS: Fifteen women and 28 men with a median age 67 years (range: 45 - 85 years) and a median follow up of 1.5 years (range: 91 days - 5.2 years) were included. Twenty five (58.1%) had CMML, 15 (34.9%) had MDS/MPN-U and 3 (7%) had aCML. Thirty-four patients (79.1%) received azacitidine (median number of cycles: 4.5, range: 1 - 65) and 9 patients (20.9%) received decitabine (median number of cycles: 4, range: 3 - 21). Seventeen patients (39.5%) underwent BMT following HMA therapy. The incidence of AML transformation was 16%. No patients had CR while 56% achieved a PR and 42% had an MR. Univariate analysis showed that ≥2 HR mutations (OR 0.19, 95% CI 0.05-0.67), SETBP1 mutation (OR 0.16, 95% CI 0.02-0.76), RUNX1 mutation (OR 0.1, 95% CI 0.01-0.48) and a mutation in at least one out of the SETBP1, RUNX1 and EZH2 genes (OR 0.05, 95% CI 0.01-0.21) were associated with absence of PR. ≥2 HR mutations (OR 0.23, 95% CI 0.05-0.9), and the presence of a mutation in one out of the SETBP1, RUNX1 and EZH2 genes (OR 0.16, 95% CI 0.03-0.62) were associated with absence of MR on univariate analysis. Finally, older age as a continuous variable was associated with PR (OR 1.09, 95% CI 1.01-1.19) and MR (OR 1.12, 95% CI 1.03-1.24). Presence of a mutation in one of the SETBP1, RUNX1 and EZH2 genes with age adjusted was selected from LASSO approach and significantly predicted the absence of PR (OR 0.05, 95% CI 0.01-0.27), and MR (OR 0.19, 95% CI 0.04-0.91) (Table 1). Using the landmark of 6 months after the initiation of treatment, Kaplan-Meier analysis showed that PR at 6 months was associated with superior overall survival (P=0.010) compared to patients with no response (Figure 1). Similarly, Cox-regression analysis revealed that the occurrence of PR following the initiation of treatment was associated with better overall survival (HR 0.26, 95% CI 0.9-0.13, P=0.010). CONCLUSIONS: Mutations in SETBP1, RUNX1 or EZH2 genes predicted absence of response to HMA among patients with MDS/MPN independent of other factors including karyotype, blast percentage and R-IPSS. These findings suggest that the molecular profile of MDS/MPN patients can potentially identify patients with HMA-refractory phenotype. Multi-institutional studies of larger cohorts are required to verify these results and develop novel treatment strategies especially for patients with high-risk mutations in MDS/MPN. Figure 1. Kaplan-Meier estimates of OS by PR status at 6 months in landmark analysis. P-value was based on log-rank test. Figure 1 Figure 1. Disclosures Levis: BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Jazz: Consultancy, Honoraria; Amgen, Astellas Pharma, Daiichi-Sankyo, FujiFilm, and Menarini: Honoraria; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Astellas and FujiFilm: Research Funding; Pfizer: Consultancy, Honoraria; Takeda: Honoraria. Jain: Syneos Health: Research Funding; CTI Biopharma: Research Funding; CareDx: Other: for advisory board participation; Bristol Myers Squibb: Other: for advisory board participation; Targeted Healthcare Communications: Consultancy.


2021 ◽  
Vol 64 (17) ◽  
pp. 12651-12669
Author(s):  
Leah L. Lowder ◽  
Matthew Powell ◽  
Sean E. Miller ◽  
Rigel J. Kishton ◽  
Charles B. Kelly ◽  
...  

Cancers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 4064
Author(s):  
Raghu Radhakrishnan ◽  
Hannah L. Crane ◽  
Marc Daigneault ◽  
Kanaka Sai Ram Padam ◽  
Keith D. Hunter

Loss of RARβ2 expression by promoter methylation is an early event in oral carcinogenesis. Understanding the mechanisms and consequences of RARβ loss may aid in understanding the disappointing results of retinoid chemoprevention trials. This study aimed to describe the effects of all-trans retinoic acid (ATRA) and the de-methylating agent 5-Aza-2′ deoxycytidine (5-AZA-CdR) on a panel of immortal potentially malignant oral lesion (PMOL) cell cultures. RARβ expression was assessed in PMOL tissues by immunohistochemistry. Cells were treated with ATRA ± 5-AZA-CdR, and the effects on the cell cycle and senescence were assessed. In PMOL tissues, RARβ expression was variable, but lower in biopsies which gave rise to immortal cell cultures. Treatment of iPMOL cells with ATRA resulted in little change in RARβ expression, but the addition of 5-AZA-CdR resulted in significant increases. The effects on the cell cycle and senescence were variable and may be related to 5-AZA-CdR, as this has wider effects on the cell cycle. Overall, the response of iPMOL cells to ATRA and 5-AZA-CdR treatment was variable and is dependent on several factors, including RARβ-promoter methylation. These findings may help to explain the lack of consistent effect of retinoids in PMOLs seen in chemoprevention trials. 


2021 ◽  
Vol 01 ◽  
Author(s):  
Saad Moulay

: C-Methylation of organic substrates was accomplished with a number of methylating agents other than methane, methanol, and methyl metals. They include methyl halides (MeX, X = I, Br, Cl, F), methyl-containing halogenated reagents, methyl peroxides, dimethyl carbonate (DMC), dimethylsulfoxide (DMSO), N,N-dimethyl formamide (DMF), diazomethane, formate salts, trioxane, CO/H2, CO2/H2, and dimethyl ether (DME). Under particular conditions, some methyl-containing molecules such as polymethylbenzenes, methylhydrazine, tris(diethylamino)sulfonium difluorotrimethylsilicate, methyl tosylate, long-chain alkyl alcohols, and acetic acid unexpectedly C-methylated a variety of organic substrates. A few cases of C-methylation only were reported to occur in the absence of catalysts. Otherwise, transition metal complexes as catalysts in conjunction with specific ligands and bases were ubiquitously present in most C-methylation reactions. Of the reactions, Suzuki-Miyaura-type cross-coupling remained of paramount importance in making 11CH3-bearing positron emission tomography tracers (PETs), one of the best applications of such methylation. Methylation proceeded at C(aromatic)-X, C(sp3)-X C(sp2)-X, and C(sp)-X of substrates (X = H, halogen). Ortho-methylation was regioselectively observed with aromatic substrates when they bear moieties such as pyridyl, pyrimidyl, amide, and imine functionalities, which were accordingly coined ‘ortho-directing groups’.


Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 531
Author(s):  
Haifang Mao ◽  
Xiaolei Li ◽  
Fen Xu ◽  
Zuobing Xiao ◽  
Wenxiang Zhang ◽  
...  

Guaiacol (2-methoxyphenol), an important fine chemical intermediate, is conventionally synthesized by liquid-phase processes with expensive, corrosive and toxic methylating agents such as dimethyl sulphate and dimethyl iodide. Recently, vapour-phase alkylation of catechol (1, 2-dihydroxybenzene) with methanol for the synthesis of guaiacol in the presence of heterogeneous catalysts has received more attention, as the route is economical and environmentally friendly. However, most of the investigated catalysts exhibited unsatisfactory catalytic performance for industrial applications. In this study, five metal phosphates M-P-O (M = La, Ce, Mg, Al, Zn) catalysts were synthesized and tested in the selective O-methylation of catechol with methanol. Among these catalysts, cerium phosphate (CP) showed the highest catalytic activity and guaiacol yield. Lanthanum phosphate (LP) was the second most active, which was still obviously better than magnesium phosphate (MP) and aluminium phosphate (ALP). Zinc phosphate (ZP) was not active in the reaction. Relevant samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), N2 adsorption-desorption, temperature programmed desorption of NH3 or CO2 (NH3-TPD, CO2-TPD). The suitable acid-base properties contribute to the superior catalytic performance of CP. Long-term stability and regeneration tests were also studied.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
B. Altakroni ◽  
C. Nevin ◽  
M. Carroll ◽  
C. Murgatroyd ◽  
G. Horne ◽  
...  

AbstractSperm DNA contains a range of DNA base damage that can arise, in part, from exposure to methylating agents. However, the effects are not fully characterized and so the aim of this study was to investigate associations between semen quality and the levels of N7-methyldeoxyguanosine (N7-MedG), a marker of exposure to methylating agents, and other markers of DNA damage and DNA methylation. Sperm samples were collected from 105 men attending an assisted reproduction clinic as part of a couple undergoing treatment for infertility and semen quality assessed manually according to WHO guidelines. Semen levels of N7-MedG, quantified by immunoslotblot, were significantly higher in men with sperm concentration < 15 × 106/ml (p ≤ 0.01), semen volume < 1.5 ml (p ≤ 0.05) and also in men with any aspect of semen quality below WHO reference levels (p ≤ 0.001). Measures of neutral Comet DNA damage were correlated with semen quality in a univariate analysis but not after adjustment for N7-MedG levels. Sperm concentration was negatively associated with % methylation at the gene for DAZL but no other marker of global or gene-specific DNA methylation. Results support the hypothesis that the known toxic and DNA damaging properties of alkylating agent exposure may have direct deleterious consequences on semen quality.


Author(s):  
N.V. ROMANOV ◽  

On model fi stula sheep, the eff ect of feeding a form of choline “protected” from the indirect eff ects of symbiotic microfl ora as a source of methylating agents on pregastric digestion, digestibility, and use of nutrients of feed in the body was studied. An increase in the amount of digested nutrients of feed, an improvement in the indicators of carbohydrate-fat and protein metabolism in the body of animals receiving choline was established, which gives grounds for its use in sheep breeding.


2020 ◽  
Vol 50 (5) ◽  
pp. 526-551
Author(s):  
Jingyi Bai ◽  
Yunfei Zhao ◽  
Zhuangzhi Shi ◽  
Minyan Wang ◽  
Hongjian Lu

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