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Khabirova, E.

Publications and source records attributed to Khabirova, E..

5 recordsLinked to original sources

Decoding The Nuclear Genome of The Human Pathogen Babesia duncani Shed Light on its Virulence, Drug Susceptibility and Evolution among Apicomplexa

Babesia species are tick-transmitted apicomplexan pathogens and the causative agents of babesiosis, a malaria-like disease of major medical and veterinary importance. Of the different species of Babesia reported so far, Babesia duncani causes severe to lethal infection in patients. Despite the highly virulent nature of this parasite and the risk it may pose as an emerging pathogen, little is known about its biology, metabolic requirements, and pathogenesis. B. duncani is unique among apicomplexan parasites that infect red blood cells in that it can be continuously cultured in vitro in human erythrocytes but can also infect mice leading to fulminant babesiosis infection and death. Here we have taken advantage of the recent advances in the propagation of this parasite in vitro and in vivo to conduct detailed molecular, genomic and transcriptomic analyses and to gain insights into its biology. We report the assembly, 3D structure, and annotation of the nuclear genome of this parasite as well as its transcriptomic profile and an atlas of its metabolism during its intraerythrocytic life cycle. Detailed examination of the B. duncani genome and comparative genomic analyses identified new classes of candidate virulence factors, suitable antigens for diagnosis of active infection, and several attractive drug targets. Translational analyses and efficacy studies identified highly potent inhibitors of B. duncani thus enriching the pipeline of small molecules that could be developed as effective therapies for the treatment of human babesiosis.

microbiology↗

Single cell mRNA signals reveal a distinct developmental state of KMT2A-rearranged infant B-cell acute lymphoblastic leukemia

Infant B-cell acute lymphoblastic leukemia (B-ALL) has not followed the increasing trend towards cure seen in other childhood B-ALLs. The prognosis for infants with KMT2A gene fusions is especially poor, and the origins of this aggressive leukemia remain unknown. Here, we investigated the developmental state of KMT2A-rearranged infant B-ALL within hematopoietic hierarchies of human fetal bone marrow, using bulk mRNA meta-analysis of childhood leukemia and examination of single lymphoblast transcriptomes. KMT2A-rearranged infant B-ALL was uniquely dominated by an early lymphocyte precursor (ELP) state. Direct comparison of infant lymphoblasts with ELP cells distilled the core oncogenic transcriptome of cancer cells which harboured potentially targetable hybrid myeloid-lymphoid features. Overall our quantitative molecular analyses demonstrate a distinct developmental state of KMT2A-rearranged infant B-ALL.

genomics↗

Precise identification of cancer cells from allelic imbalances in single cell transcriptomes

A fundamental step of tumour single cell mRNA analysis is separating cancer and non-cancer cells. We show that the common approach to separation, using shifts in average expression, can lead to erroneous biological conclusions. By contrast, allelic imbalances representing copy number changes directly detect the cancer genotype and accurately separate cancer from non-cancer cells. Our findings provide a definitive approach to identifying cancer cells from single cell mRNA sequencing data.

genomics↗

Tumor to normal single cell mRNA comparisons reveal a pan-neuroblastoma cancer cell

Neuroblastoma is an embryonal childhood cancer that arises from aberrant development of the neural crest, mostly within the fetal adrenal medulla. It is not established what developmental processes neuroblastoma cancer cells represent. Here, we sought to reveal the phenotype of neuroblastoma cancer cells by comparing cancer (n=16,591) with fetal adrenal single cell transcriptomes (n=57,972). Our principal finding was that the neuroblastoma cancer cell resembled fetal sympathoblasts, but no other fetal adrenal cell type. The sympathoblastic state was a universal feature of neuroblastoma cells, transcending cell cluster diversity, individual patients and clinical phenotypes. We substantiated our findings in 652 neuroblastoma bulk transcriptomes and by integrating canonical features of the neuroblastoma genome with transcriptional signals. Overall, our observations indicate that there exists a pan-neuroblastoma cancer cell state which may be an attractive target for novel therapeutic avenues.

cancer biology↗

Cellular mRNA signals in human kidney tumors

The cellular transcriptome may provide clues into the differentiation state and origin of human cancer, as tumor cells may retain patterns of gene expression similar to the cell they derive from. Here, we studied the differentiation state and cellular origin of human kidney tumors, by assessing mRNA signals in 1,300 childhood and adult renal tumors, spanning seven different tumor types. Using single cell mRNA reference maps of normal tissues generated by the Human Cell Atlas project, we measured the abundance of reference "cellular signals" in each tumor. Quantifying global differentiation states, we found that, irrespective of tumor type, childhood tumors exhibited fetal cellular signals, thus replacing the long-held presumption of "fetalness" with a precise, quantitative readout of immaturity. By contrast, in adult cancers our assessment refuted the suggestion of dedifferentiation towards a fetal state in the overwhelming majority of cases, with the exception of lethal variants of clear cell renal cell carcinoma. Examining the specific cellular phenotype of each tumor type revealed an intimate connection between the different mesenchymal populations of the developing kidney and childhood renal tumors, whereas adult tumors mostly represented specific mature tubular cell types. RNA signals of each tumor type were remarkably uniform and specific, indicating a possible therapeutic and diagnostic utility. We demonstrated this utility with a case study of a cryptic renal tumor. Whilst not classifiable by clinical pathological work-up, mRNA signals revealed the diagnosis. Our findings provide a cellular definition of human renal tumors through an approach that is broadly applicable to human cancer.

cancer biology↗