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Ghafoor, S.

Publications and source records attributed to Ghafoor, S..

3 recordsLinked to original sources

Phenotype-dependent subtyping exposes high MYC activity as a targetable dependency in LuAd

C-MYC (MYC) occupies a critical nexus of oncogenic signalling and deregulated expression of MYC is widespread across most human cancer types, suggesting that MYC should be an attractive target for therapeutic intervention. Although 30-40% of human Non-Small Cell lung cancers show low level amplification of c-MYC and genetic evidence has shown that c-Myc is a key downstream effector of KRas-driven lung tumourigenesis in mouse models, the functional contribution of MYC to human lung cancer remains unclear. We applied a phenotype-based classifier to the TCGA Lung Adenocarcinoma (LuAd) cohort and found that high MYC transcriptional activity identifies a subset of LuAd with significantly reduced survival. Application of the same methodology to a panel of genetically engineered mouse models identified multiple genotypes that give rise to the high MYC activity phenotype, disease positioning such models as reflective of a distinct subset of human LuAd. We show that high MYC activity predicts sensitivity to a small molecule dual-inhibitor of the MYC co-factors, EZH2 and G9A, HKMTi-1-005, and that treatment with HKMTi-1-005 strongly reduced MYC protein expression, induced B cell-mediated immune surveillance and suppressed growth of autochthonous KRasG12D-driven lung tumours. Statement of significanceThis work establishes the principle of indirectly targeting MYC in LuAd, via inhibition of associated enzymatic cofactors, EZH2 and G9A, and identifies a large subset of aggressive human LuAd with a high MYC activity signature that may benefit from this approach.

cancer biology↗

Mapping antibiotic resistance determinants in oral streptococci

BackgroundAntibiotic resistance is a global priority in healthcare. Leveraging thousands of whole-genome sequences, here we reveal the core resistance determinants of oral streptococci, focusing on assessing pattern variability and gene exchange across commensals and pathogens. MethodsGenomic information was obtained from the National Center for Biotechnology Information. Determinants of antibiotic resistance were identified using AMRFinderPlus and CARD. ICEscreen was employed for calling of integrative and conjugative elements. Variability and recombination in penicillin-binding protein sequences were assessed with MMseqs2 and fastGEAR. ResultsA total of 2,087 genomes from 15 species were included with members from the mitis, mutans, anginosus, salivarius, and bovis groups. We observed 3,576 hits from 55 unique resistance genes conferring resistance to 11 antibiotic classes. The species with most resistance determinants per genome were identified as Streptococcus mitis (2.7), Streptococcus oralis (2.5), Streptococcus parasanguinis (1.9), Streptococcus gallolyticus (1.3), and Streptococcus anginosus (1.2). The two latter species also presented the most diverse composition of determinants. Over 1,800 integrative and conjugative elements were shown across all genomes, with nearly 18% of them carrying at least one antibiotic resistance gene. Penicillin-binding protein variation analyses showed a high diversity in the mitis group. Even though S. mitis and S. oralis composed less than 4% of the genomes included in the analyses, they were recognized as sources of DNA for over a third of recombination events in pbp1a and nearly half for both pbp2b and pbp2x in resistant isolates of Streptococcus pneumoniae. ConclusionsWe show that tetracycline and macrolide resistance were highly abundant and tightly connected to integrative and conjugative elements. Further, recent recombination data show frequent genetic exchange from oral streptococci to beta-lactam-resistant S. pneumoniae. Finally, assessing the dynamics of genetic exchange across species is central for the development of strategies to mitigate the impact of antibiotic resistance.

microbiology↗

Coordinated multiple cellular processes in tongue development

Dysfunction of primary cilia leads to genetic disorder, ciliopathies, which shows various malformations in many vital organs such as brain. Multiple tongue deformities including cleft, hamartoma and ankyloglossia are also seen in ciliopathies, which yield difficulties in fundamental functions such as mastication and vocalization. Here, we found these tongue anomalies in mice with mutation of ciliary protein. Abnormal cranial neural crest-derived cells (CNCC) failed to evoke Hh signal for differentiation of mesoderm-derived cells into myoblasts, which resulted in abnormal differentiation of mesoderm-derived cells into adipocytes. The ectopic adipose subsequently arrested migration of other mesoderm-derived cells and CNCC. Some aberrant CNCC abnormally differentiated into osteoblasts due to the lack of Hh signal, which migrated into tongue to form ectopic bone. Ankyloglossia was caused by aberrant cell migration due to lack of non-canonical Wnt signaling. In addition to ciliopathies, these tongue anomalies are often observed as non-familial condition in human. We found that these tongue deformities could be reproduced in wild-type mice by simple mechanical manipulations in CNCC to disturb cellular processes which were disrupted in mutant mice. Thus, tongue development requires coordinated multiple cellular processes (cell-cell contact, migration and differentiation). Our results provide hints for possible future treatment in ciliopathies.

developmental biology↗