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Generally, EMT, Epithelial to Mesenchymal Transitionchanism is thought to be involved in the mechanism in which cancer cells metastasize in the early stage. EMT is an process in which epithelial cells depolarize and lose their cell-to-cell contacts, and gain mesenchymal morphology. The mesenchymal cells is capable of reaching distant sites through blood vessels. So, EMT is thought to a necessary mechanism for metastasis. However, I found a surprising report from Nature Article indicating that EMT isn't required for metastasis. Kari R. Fischer et al., 2015,Nature. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4662610/ They established an EMT lineage-tracing system in mice with the mammary tumors to monitor metastasis of the epithelial cancer cells to lung through EMT using epithelial-specific and mesenchymal-specific markers. This report showed that a small proportion of cancer cells underwent EMT and lung metastasis mainly consisted of epithelial cells which didn't undergo EMT. I think this report is innovative and overthrows the commonly accepted thought that EMT is necessary for metastasis, However, some questions come to me. How the epithelial cancer cells gain the motility and metastasize without undergoing EMT？ How do you think of this report？ Please tell me some related reports if you have.

I think the most important thing is whether viruses are incorporated by endocytosis into the cells. When viruses are incorporated, they are transported to the acidic environment in the cells. Some viruses are covered with viral envelopes to protect their protein capsids. In acid condition, viral envelops are degraded and after that, viral DNA, RNA and proteins are released out of viral envelops. This released DNA and RNA are used for proliferation of viruses. So, acidic environment is necessary for incorporated viruses to proliferate. On the other hand, such an acidic environment is lethal for not incorporated viruses because not incorporated viruses release their DNA or RNA to the extracellular region not to host's nucleus, so in the case they can't proliferate.

Hi, everyone!! Recently an interesting study has reported. Zhou et al., 2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201605101 According to this study, enhancing anterograde axon transport of mitochondria is essential for regeneration of injured axons. Neurons need a large amount of energy provided by ATP to extend their exons when they are injured. Mitochondria produces ATP essential for neuron growth, survival and regeneration. This study shows that in mature neurons, the motility of mitochondria is reduced and the reduced mitochondrial motility might be the cause of the deficit in regrowth capacity of mature neurons. Moreover, this study found that enhancing mitochondria transport enables mature neurons to recover their regrowth capacity. It is said that mature neurons typically arrest their cell cycle and fail to proliferate and regrow. However, considering the fact that only enhancing mitochondria transport enables mature neuron to recover their regrowth capacity, I can't help but doubt the commonly accepted theory. Don't mature neurons actually arrest their cell cycle？ How do you think of this finding ？ Thank you