Biology subjects

Kang, M. H.

Publications and source records attributed to Kang, M. H..

6 recordsLinked to original sources

bioRxiv2026

Selective Elimination of TP53 Mutant Cells by Transcript-Activated Chromatin Shredding

Genetic mutations that drive cancer often occur in tumor suppressor proteins, including the p53 transcription factor which is altered in [~]40-50% of cases1,2. However, current therapies fail to target most such mutations because the mutant proteins typically lack defined drug-binding pockets, and restoring the endogenous function has proven challenging. Here, we programmed CRISPR-Cas12a2, an RNA-guided nuclease with trans-nucleolytic cleavage activities3,4, to selectively kill cancer cells by targeting cancer-specific transcripts. This approach eliminates cells by inducing trans chromatin cleavage, triggering DNA damage and cell death. Unlike existing methods, RNA-guided Cas12a2 senses cellular RNA signatures to shred chromatin, enabling precise targeting of undruggable mutations. Transcript-activated chromatin shredding provides an innovative paradigm to develop precision disease treatments for undruggable targets.

cell biology↗

bioRxiv2026

Amplified genome editing by in vivo editor production

Genome editing enzymes have vast therapeutic potential. However, achieving sufficient delivery in vivo remains a major challenge, because editing machinery is confined to the subset of transfectable cells in a tissue. Here, we tested the possibility that genome editing could be amplified in vivo by enabling transfected cells to transfer editing enzymes to neighboring cells. Our data show that this NANoparticle-Induced Transfer of Enzyme (NANITE) strategy quadrupled editing efficiency in cultured cells relative to non-spreading controls. A single intravenous injection of the NANITE plasmid into mice induced ~3-fold higher levels of liver editing at the transthyretin (Ttr) locus relative to non-spreading controls, with corresponding reductions in serum TTR levels. Spreading therapeutic enzymes offers a nonviral and non-infectious strategy to boost therapeutic effects after delivery.

bioengineering↗

bioRxiv2025

Levels of telomerase in cancer are contingent on senescence and inflammation at bulk tissue and single-cell spatial resolution

Telomerase activity plays a critical role in tumor growth and is quantified based on its level of expression. However, how these levels are associated with different pathways across various cancer types remains elusive due to the lack of a classification schema. Here, we defined an unsupervised learning metric for the quantitative measurement of telomerase activity and robustly classified the samples into low and high telomerase groups across different cancers. Using this classification system, we analyzed the data for over 9000 bulk tumors, single cells, and spatially organized tissues, and we found that telomerase high groups across the majority of cancers are strongly associated with genomic instability. On the contrary, lower group of telomerase across various cancers are significantly associated with cellular senescence, inflammation, ROS, and MAPK pathway activities. Cellular senescence, a hallmark of cellular aging, was dominant in older adults over the high telomerase levels in the majority of cancers, normal tissues, and human development phases. Our study comprehensively illustrates that lower levels of telomerase are associated with senescence-phenotype in the majority of cancers, which is strongly favorable for better survival outcomes.

bioinformatics↗

bioRxiv2023

Engineering self-deliverable ribonucleoproteins for genome editing in the brain

The delivery of CRISPR ribonucleoproteins (RNPs) for genome editing in vitro and in vivo has important advantages over other delivery methods, including reduced off-target and immunogenic effects1. However, effective delivery of RNPs remains challenging in certain cell types due to low efficiency and cell toxicity. To address these issues, we engineered self-deliverable RNPs that can promote efficient cellular uptake and carry out robust genome editing without the need for helper materials or biomolecules. Screening of cell-penetrating peptides (CPPs) fused to CRISPR-Cas9 protein identified potent constructs capable of efficient genome editing of neural progenitor cells. Further engineering of these fusion proteins identified a C-terminal Cas9 fusion with three copies of A22p, a peptide derived from human semaphorin-3a, that exhibited substantially improved editing efficacy compared to other constructs. We found that self-deliverable Cas9 RNPs generated robust genome edits in clinically relevant genes when injected directly into the mouse striatum. Overall, self-deliverable Cas9 proteins provide a facile and effective platform for genome editing in vitro and in vivo.

bioengineering↗

bioRxiv2023

Genome editing in the mouse brain with minimally immunogenic Cas9 RNPs

Transient delivery of CRISPR-Cas9 ribonucleoproteins (RNPs) into the central nervous system (CNS) for therapeutic genome editing could avoid limitations of viral vector-based delivery including cargo capacity, immunogenicity, and cost. Here we tested the ability of cell penetrant Cas9 RNPs to edit the mouse striatum when introduced using a convection enhanced delivery system. These transient Cas9 RNPs showed comparable editing of neurons and reduced adaptive immune responses relative to one formulation of Cas9 delivered using AAV serotype 9. The production of ultra-low-endotoxin Cas9 protein manufactured at scale further improved innate immunity. We conclude that injection-based delivery of minimally immunogenic CRISPR genome editing RNPs into the CNS provides a valuable alternative to virus-mediated genome editing.

bioengineering↗

bioRxiv2021

Optical bench simulation for intraocular lenses using field-tracing technology

PurposeTo evaluate the image quality of intraocular lenses (IOLs) using field-tracing optical simulation and then compare it with the image quality using conventional ray-tracing simulation. MethodsWe simulated aspheric IOLs with a decenter, tilt, and no misalignment using an aspheric corneal eye model with a positive spherical aberration. The retinal image, Strehl ratio, and modulation transfer function (MTF) were compared between the ray-tracing and field-tracing optical simulation and confirmed by the results reported in an in vitro experiment using the same eye model. ResultsThe retinal image showed interference fringes from target due to diffraction from the object in a field-tracing simulation. When compared with the experimental results, the field tracing represented the experimental results more precisely than ray tracing after passing over 400 {micro}m of the decentration and 4 degrees of the tilt of the IOLs. The MTF values showed similar results for the case of no IOL misalignment in both the field tracing and ray tracing. In the case of the 200-{micro}m decentration or 8-degree tilt of IOL, the field-traced MTF shows lower values than the ray-traced one. ConclusionsThe field-tracing optical bench simulation is a reliable method to evaluate IOL performance according to the IOL misalignment. It can provide retinal image quality close to real by taking into account the wave nature of light, interference and diffraction to explain to patients having the IOL misalignment.

bioinformatics↗