Dr. Marietta Jank - Best of the Best in Pediatric Surgery 2025

All right, we've got, uh, we've got now moving on, that was paps. Now it's time to bring on caps. Uh, so we've got, uh, Dr. Marietta Jank, who's talking about cited 2 is disrupted in human congenital diaphragmatic hernia in, uh, CDH in CDH lungs. So, uh, let's bring it up. Thank you very much for the opportunity to present our data on cited 2 in human CDH lungs. We have no conflicts of interest to disclose. Congenital diaphragmatic hernia, CDH is characterized by a diaphragmatic defect and abnormal lung development with varying degrees of pulmonary hypoplasia and hypertension. Approximately 25% of CDH patients have concurrent cardiac anomalies. So why are we interested inside it too? Lung development is orchestrated by the activation and inhibition of transcription factors. Cited 2 is a transcriptional modulator and can be induced by hypoxia, interlukins, interferon gamma, TNF alpha and LPS. It binds with high affinity to coactivators regulating transactivation of multiple transcription factors, such as HIF 1 alpha, NF Kappa B, PPR gamma, and Smet 2 and 3. Cited 2 null mutant mice and rats are embryonic and perinatal lethal, or in the case of the rats die within the first few hours after birth, exhibiting lung and cardiac anomalies. Cited 2 is required for lung maturation and is detected in the septum transversum of the developing diaphragm. Cited 2, therefore, is critical for the development of heart, lung, and diaphragm, and therefore an interesting candidate in the pathogenesis of CDH. We previously published our results on cited 2 in the nitrofen rat model. We induced CDH by gavage at embryonic day 9.5 and investigated the lungs of the pups at embryonic day 15, 18 and 21 using real-time QPCR, in situ hybridization, and immunofluorescence. At E15, we did not see a difference. At E18, there was a decreased expression of cited 2, which proved to be significant in the in situ hybridization staining. Interestingly, at embryonic stage 21, there was an increased expression of cited 2 in both the in situ hybridization and on a QPCR level. We confirmed this on a protein level where we saw an increased staining in the epithelial layer of cited 2 in nitrophen induced lungs. For the translatability, we investigated cited 2 in human fetal CDH and control lungs at antistation. We saw a similar pattern as in the nitrofen model with a significantly increased abundance of cited 2 in the CDH lungs. Single case reports in literature report abertations at the chromosomal location of cited 2 on chromosome 6. We looked at our genomic sequencing results of isolated CDH patients and found a hotspot at the coordinates for cited 2. As you can see marked in the yellow box for the isolated CDH patients compared to the controls of the bottom. So how do we interpret these results? We suggest that cited 2 may play a minor role in early lung development. At E15, we did not show a difference between CDH and control lungs. Literature describes that cited 2 expression is low at early lung development, and cited 2 deficient mice showed no difference in the lung phenotype compared to controls at embryonic day 16.5. While at E18, cited 2 may promote pulmonary maturation. We showed a decreased expression of cited 2 in CDH lungs. In line with these results, cited 2 null mutant mice embryos at E17.5 and 18.5 showed signs of pulmonary immaturity with smaller lobe size, increased percentage of tissue and loss of air space. A similar phenotype we see in CDH and cited 2 mutant rats shown a rest at cacular stage. While at antistation, i.e., E21, the scale seems to tip over and we saw an increased expression of cited 2. So we hypothesize that cited 2 orchestrates the inflammatory response in nitrofen induced abnormal lung development. Current literature has shown that cited 2 itself is induced by proinflammatory stimuli, like LPS, interlukans, interferon gamma and TNF alpha. Our podiomic data showed an alterate inflammatory pathways at E21 nitrophen lungs with an increased abundance of CBP, NF Kappa B and stat 3, which are all interacting factors of cited 2. So we put forward that cited 2 may be induced by NF Kappa B signaling and acts as a negative feedback regulation of NF Kappa B in the nucleus. So to summarize, cited 2 may be important for later stages of lung development and we could show a disregulation of cited 2 also in human CDH. I would like to thank the team who helped me realize this project and you for listening. Thank you so much for that. Um, I failed to mention Marietta your institution when I introduced you, University of Manitoba. Uh, this paper shows I was I had the pleasure of visiting you last year there and it was it's an incredible place and this paper shows that. So incredible work. Uh, uh Laura, you had a question. Yes, thanks so much, uh, Dr. Jank for presenting. I think having the example of the histology and that fetal patient, um, and the human is really important, uh, to see what it looks like outside of that nitrofin model. Um, but I was curious, right now it seems a little bit like a hypothesis that the cited 2 was part of the lung maturation process. Do you have a next step of what you're going to look look at to see if it's more of a true, um, cause and effect rather than just association? Yeah, thank you for the question. Um, in fact, yes. So, um, it's very tricky with cited 2 because it's so ubiquitously, um, expressed, um, throughout, um, development. Um, but we in fact, um, um are collaborating with, um, Kansas University for apercast 9 cited to mutant rat, because that's always a little bit tricky when we talk about the nitro model is that we don't have, like we can't use mice, um, as efficiently as the rat. And so we are happy to be collaborating and looking closer at, um, the lung morphology, um, throughout development and as you say, to kind of pinpoint, um, the hypothesis whether, um, it is an effect of inflammation, so whether inflammation induces cited to, um, or whether cited to kind of inhibits via a negative feedback loop when there is an inflammation, which is a hypothesis in the pathogenesis of abnormal lung development at late gestation in CDH. Perfect timing, great paper. Thank you very much. All right. Thank you so much.