Therapeutic targeting of EP300/CBP by bromodomain inhibition in hematologic malignancies

CCS1477 (inobrodib) is a potent, selective EP300/CBP bromodomain inhibitor which induces cell-cycle arrest and differentiation in hematologic malignancy model systems. In myeloid leukemia cells, it promotes rapid eviction of EP300/CBP from an enhancer subset marked by strong MYB occupancy and high H3K27 acetylation, with downregulation of the subordinate oncogenic network and redistribution to sites close to differentiation genes. In myeloma cells, CCS1477 induces eviction of EP300/CBP from FGFR3, the target of the common (4; 14) translocation, with redistribution away from IRF4-occupied sites to TCF3/E2A-occupied sites. In a subset of patients with relapsed or refractory disease, CCS1477 monotherapy induces differentiation responses in AML and objective responses in heavily pre-treated multiple myeloma. In vivo preclinical combination studies reveal synergistic responses to treatment with standard-of-care agents. Thus, CCS1477 exhibits encouraging preclinical and early-phase clinical activity by disrupting recruitment of EP300/CBP to enhancer networks occupied by critical transcription factors.

Novel transaminases from thermophiles: from discovery to application

Transaminases (TAs) are promising biocatalysts for chiral amine synthesis; however, only few thermophilic TAs have been described to date. In this work, a genome mining approach was taken to seek novel TAs from nine thermophilic microorganisms. TA sequences were identified from their respective genome sequences and their Pfam were predicted confirming that TAs class I–II are the most abundant (50%), followed by class III (26%), V (16%), IV (8%) and VI (1%). The percentage of open reading frames (ORFs) that are TAs ranges from 0.689% in Thermococcus litoralis to 0.424% in Sulfolobus solfataricus. A total of 94 putative TAs were successfully cloned and expressed into E. coli, showing mostly good expression levels when using a chemical chaperone media containing d‐sorbitol. Kinetic and end‐point colorimetric assays with different amino donors–acceptors confirmed TAs activity allowing for initial exploration of the substrate scope. Stereoselective and non‐stereoselective serine‐TAs were selected for the synthesis of hydroxypyruvate (HPA). Low HPA reaction yields were observed with four non‐stereoselective serine‐TAs, whilst two stereoselective serine‐TAs showed significantly higher yields. Coupling serine‐TA reactions to a transketolase to yield l‐erythrulose (Ery) substantially increased serine conversion into HPA. Combining both stereoselective serine‐TAs and transketolase using the inexpensive racemic D/L‐serine led to high Ery yield (82%). Thermal characterization of stereoselective serine‐TAs confirmed they have excellent thermostability up to 60°C and high optimum temperatures.

Maori/non-Maori patterns of contact, expressed morbidity and resource use in general practice: data from the Waikato Medical Care Survey 1991-2

AIMS

To compare patterns of contact, expressed morbidity and resource use in primary care for a representative sample of patients of Maori and non-Maori background.

METHODS

The data are drawn from a survey of general practice in the Waikato region representing a one per cent sample of all week day encounters. The data were recorded by participating general practitioners in four collection weeks spaced over the period of a year. In total, 12,833 patient encounter forms were completed.

RESULTS

Annual rates of general practitioner contact for Maori are slightly lower than those for patients of non-Maori background. The case-mix pattern of general practitioner contact is very similar between the two groups. There is a limited correspondence between ethnic patterns of general practitioner usage and health need (as measured by mortality levels and rates of public hospital discharge).

CONCLUSIONS

The near equivalence in ethnic rates of general practitioner contact revealed in this study contrasts strikingly both with the level of hospitalisation for Maori, which is nearly double that of non-Maori, and with the difference in mortality rates (30% higher for Maori). Attention devoted to improving access to general practitioner services among Maori may be necessary if important areas of ill health and hospital resource use are to be addressed effectively.

Bacteriuria in intermittent catheterization users: the effect of sterile versus clean reused catheters

Monthly urine cultures were analyzed at the University of Alberta Department of Medical Microbiology and Infectious Diseases to determine whether single-use sterile catheters and clean technique reduced the incidence of bacterial colonization in those using long-term intermittent self-catheterization. Thirty subjects with spina bifida, ages 3 years to 16 years, entered a crossover study with random assignment to 6 months of sterile single-use catheters or clean reused catheters. Seventeen subjects were catheterized by a parent or caregiver; 13 were responsible for self-catheterization and cleaning of the catheters. Six months of descriptive data were also collected at Alberta Children's Hospital from a similar group of subjects with spina bifida who used sterile catheters only. In the crossover group, 38% of all urine cultures were positive regardless of whether sterile single-use or clean reused catheters were employed. The other group using only sterile catheters had a 36% positive culture rate. No difference in positive cultures was found between males and females or between children who catheterized themselves and children whose parents catheterized them. The authors concluded that plastic urethral catheters may be reused.