Biology subjects

Kim, T. M.

Publications and source records attributed to Kim, T. M..

3 recordsLinked to original sources

bioRxiv2021

Widespread multi-targeted therapy resistance via drug-induced secretome fucosylation

Cancer secretome is a reservoir for aberrant glycosylation. How therapies alter this post-translational cancer hallmark and the consequences thereof remain elusive. Here we show that an elevated secretome fucosylation is a pan-cancer signature of both response and resistance to multiple targeted therapies. Large-scale pharmacogenomics revealed that fucosylation genes display widespread association with resistance to these therapies. In both cancer cell cultures and patients, targeted kinase inhibitors distinctively induced core fucosylation of secreted proteins less than 60 kDa. Label-free proteomics of N-glycoproteomes revealed that fucosylation of the antioxidant PON1 is a critical component of the therapy-induced secretome. Core fucosylation in the Golgi impacts PON1 stability and folding prior to secretion, promoting a more degradation-resistant PON1. Non-specific and PON1-specific secretome de-N-glycosylation both limited the expansion of resistant clones in a tumor regression model. Our findings demonstrate that core fucosylation is a common modification indirectly induced by targeted therapies that paradoxically promotes resistance.

cancer biology↗

bioRxiv2019

8-OxoG in GC-rich Sp1 binding sites enhances gene transcription during adipose tissue development in juvenile mice

The oxidation of guanine to 8-oxoguanine (8-oxoG) is the most common type of oxidative DNA lesion. There is a growing body of evidence indicating that 8-oxoG is not only pre-mutagenic, but also plays an essential role in modulating gene expression along with its cognate repair proteins. In this study, we investigated the relationship between 8-oxoG formed under intrinsic oxidative stress conditions and gene expression in adipose and lung tissues of juvenile mice. We observed that transcriptional activity and the number of active genes were significantly correlated with the distribution of 8-oxoG in gene promoter regions, as determined by reverse-phase liquid chromatography/mass spectrometry (RP-LC/MS), and 8-oxoG and RNA sequencing. Gene regulation by 8-oxoG was not associated with the degree of 8-oxoG formation. Instead, genes with GC-rich transcription factor binding sites in their promoters became more active with increasing 8-oxoG abundance as also demonstrated by specificity protein 1 (Sp1)- and estrogen response element (ERE)-luciferase assays in human embryonic kidney (HEK293T) cells. These results indicate that the occurrence of 8-oxoG in GC-rich Sp1 binding sites is important for gene regulation during adipose tissue development.

genomics↗

bioRxiv2018

The CD56bright CD62L+ NKG2A+ immature cell subset is dominantly expanded in human cytokine-induced memory-like NK cells

Recent studies have revealed immunological memory of NK cells. Short-term in vitro cytokine stimulation also induces NK cell memory, but heterogeneous cell subsets within the cytokine-induced memory-like (CIML) NK cells has not been elucidated. Here we found that the dominant cell subset in human CIML NK cells are immature CD56bright CD62L+cells, and they were selectively expanded CD56bright CD16- CD62L+ NK cells. Although these cells acquired KIR expression after the cytokine stimulation, sustained NKG2A expression inhibits cytotoxicity against HLA-E+ target cells. In contrast, another checkpoint molecule LAG-3 is induced mainly on KIR+ NKG2C+ minor CIML NK cells. Our findings imply targeting NKG2A and LAG-3 should be considered for CIML NK cell-based immunotherapy.

immunology↗