Biology subjects

Huntly, B.

Publications and source records attributed to Huntly, B..

3 recordsLinked to original sources

bioRxiv2023

Genetic or pharmacological inactivation of CREBBP sensitizes B-cell Acute Lymphoblastic Leukemia to Ferroptotic Cell Death upon BCL2 Inhibition

B-cell acute lymphoblastic leukemia (B-ALL) is a leading cause of death in childhood and outcomes in adults remain dismal. There is therefore an urgent clinical need for therapies that target the highest risk cases. Mutations in the histone acetyltransferase CREBBP associate with high-risk features in B-ALL and have been implicated in chemoresistance. We performed a targeted drug screen in isogenic human cell lines, identifying a number of actionable small molecules that specifically target CREBBP-mutated B-ALL. The most potent was the BCL2 inhibitor Venetoclax, which acts through a non-canonical mechanism resulting in ferroptotic cell death. CREBBP-mutated cell lines showed differences in cell-cycle, metabolism and response to oxidative stress. Lastly, we demonstrate that small-molecule inhibition of CREBBP sensitizes B-ALL cells, regardless of genotype, to Venetoclax-induced ferroptosis in-vitro and in-vivo, providing a potential novel drug combination for broader clinical translation in B-ALL.

cancer biology↗

bioRxiv2022

LGR5 targeting molecules as therapeutic agents for multiple cancer types

Leucine-rich repeat-containing G-protein receptor 5 (LGR5) has been characterised as a stem cell and cancer stem cell marker. Previous analyses of LGR5 transcript levels indicate high level expression discriminates malignancies such as colorectal cancer (CRC) and pre-B acute lymphoblastic leukaemia (pre-B ALL) from healthy tissues suggesting LGR5 protein expression may provide a molecular handle for prognosis and treatment. We have developed highly specific, high affinity antibodies to the extracellular domain of human LGR5 (-LGR5) that detect high LGR5 protein levels in colorectal cancer (CRC), hepatocellular carcinoma (HCC), and pre-B ALL. In contrast, there is low to undetectable levels of LGR5 protein in normal colon and rectal epithelia, liver, ovarian tissues, brain and immune cell types. LGR5 is rapidly internalised from the plasma membrane and trafficked to intracellular vesicular compartments including lysosomes. Treatment of high LGR5-expressing CRC and pre-B ALL cancer cell lines with an antibody-drug conjugate version of -LGR5 (-LGR5-ADC) lead to effective cell killing at nanomolar concentrations. Interventional treatment of pre-B ALL tumours with -LGR5-ADC in vivo led to rapid tumour attrition. We further demonstrated the therapeutic utility of humanised -LGR5 by using the corresponding scFv fragment for the generation of -LGR5 chimeric antigen receptors (CARs) and a Bispecific T cell Engager (BiTE). -LGR5-CAR-NK cells were effective at killing LGR5-expressing cells while -LGR5/-CD3 BiTEs induce T cell activation and killing of NALM6 cells by cytotoxic CD8+ T cells. Taken together, this study establishes -LGR5-based therapeutic modalities that effectively discriminate and target CRC, HCC and pre-B ALL tumour cells. One Sentence SummaryWe generated novel antibodies against the cancer cell marker LGR5, validated diagnostic use in prioritizing specific cancer types for targeting, and developed antibody-based therapeutics.

cell biology↗

bioRxiv2021

Transcriptional variability accelerates pre-leukemia by cell diversification and perturbation of protein synthesis

Transcriptional variability facilitates stochastic cell diversification and can in turn underpin adaptation to stress or injury. We hypothesize that it may analogously facilitate progression of pre-malignancy to cancer. To investigate this, we initiated pre-leukemia in mouse cells with enhanced transcriptional variability due to conditional disruption of the histone lysine acetyltransferase gene Kat2a. By combining single-cell RNA-sequencing of pre-leukemia with functional analysis of transformation, we show that Kat2a loss results in global variegation of cell identity and accumulation of pre-leukemic cells. Leukemia progression is subsequently facilitated by destabilization of ribosome biogenesis and protein synthesis, which confer a transient transformation advantage. The contribution of transcriptional variability to early cancer evolution reflects a generic role in promoting cell fate transitions, which, in the case of well-adapted malignancies, contrastingly differentiates and depletes cancer stem cells. In other words, transcriptional variability confers forward momentum to cell fate systems, with differential multi-stage impact throughout cancer evolution. One-sentence summaryLoss of Kat2a enhances transcriptional variability of ribosome biosynthetic programs and transiently accelerates pre-leukemia

cancer biology↗