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Khojah, R.

Publications and source records attributed to Khojah, R..

2 recordsLinked to original sources

Brain Organoids, Lessons from Fetal Neocortex Formation, and Rational Design for Quality Control

Recent widespread adoption of cerebral organoid protocols has led to many new studies assessing the human-specific features of neural diseases. However, not all organoid studies employ proper quality control, which limits the physiological relevance of their findings. Here, we discuss the stages of in vivo neocortex formation and how those stages are recapitulated in organoid protocols. We then present the first guide for real-time operator removal of maldeveloped organoids in shaking culture. Finally, we show preliminary work on an organoid imaging and mesofluidic control platform for automated quality control of organoid development. Taken together, this approach for assessing the morphological features of organoids will improve the rigor and reproducibility of organoid studies, increase effect sizes of physiologically relevant disease etiology, and pave the way for cortical organoid GMP in high-throughput. Clinical RelevanceThis establishes high-throughput, visual brain organoid quality control for disease studies and preclinical testing.

neuroscience↗

Extracellular RNA signatures of mutant KRAS(G12C) lung adenocarcinoma cells

Extracellular RNAs (exRNAs) are actively secreted from cells in membrane-bound extracellular vesicles (EVs). Diverse classes of RNAs are secreted as exRNAs, including messenger RNAs (mRNAs), long noncoding RNAs (lncRNAs), and transposable element RNAs (TE RNAs). However, the full composition and clinical utility of exRNAs secreted in response to oncogenic signaling are unknown. Here we use both affinity- and nanofiltration-based EV isolation approaches to show that mutant KRAS(G12C) signaling results in the secretion of specific lncRNAs, TE RNAs, and mRNAs, some of which are prognostic for lung adenocarcinoma (LUAD) patient survival. We found that inhibition of KRAS(G12C) signaling broadly reprograms the noncoding transcriptome, as evidenced by a substantial increase in TE RNA secretion. KRAS(G12C) inhibition also increased the abundance of secreted lncRNAs and retained intron-containing transcripts, while decreasing the mRNA content of EVs. Oncogenic KRAS(G12C) signaling was required for the secretion of mRNAs from a set of 20 genes that are significantly associated with unfavorable clinical outcomes in LUAD. Our study suggests that both coding and noncoding RNAs that are secreted in EVs may serve as KRAS(G12C)-specific signatures for diagnosing lung cancer.

genomics↗