Cancer stem cell

Tumor recurrence is regarded as the biggest predicament in cancer therapeutics: tumors did not respond to chemotherapy anymore because they are resistant to these chemical compounds. In some cases, the emergence of drug-resistant tumor cells is due to the newly acquired "stemness" of cancer stem cells (CSCs). CSCs, like other stem cells, are defined by their ability to self-renewal and to differentiate into many cell types, which in the case of CSCs are all of the cell types of its cognate tumor.

Michele Markstein from University of Massachusetts and Norbert Perrimon at Harvard Medical School declared that in animal models, currently used chemotherapy drugs have serious side effects, which induce a high degree of stem cell proliferation, resulting in tumor recurrence. They found that some of the chemotherapy drugs Ibrutinib which can prevent the rapid growth of the tumor cells could have the opposite effect with cancer stem cells, causing them to excessive proliferation. This is very surprising, even in vivo the same drug within one animal model has different effects: inhibition of tumor growth in a population of cells, while promoting the growth of the other cell population.

This research not only has important clinical implications, but also shows the new tools for drug evaluation – Drosophila intestinal stem cells. If you want to reevaluate all the FDA-Approved Anti-cancer Drugs, you can easily get them.

Ref.

1. M. S. Wicha, Targeting self-renewal, an Achilles’ heel of cancer stem cells. Nature medicine 20, 14 (Jan, 2014).

2.M. Markstein et al., Systematic screen of chemotherapeutics in Drosophila stem cell tumors. Proceedings of the National Academy of Sciences of the United States of America, (Mar 10, 2014).

IPS Cells

The Japanese lab is going to investigate its stem cell and reprogramming research. A Japanese government-funded laboratory said that the "inappropriate handling" data was found in a widely sensational stem-cell research paper published in Nature journal.

The whole story was originated from two papers published in January 2014 described a simple way to reprogram mature mouse cells back into an embryonic-like Doxorubicin shape and to obtain pluripotency to generate all types of tissue, offering hope for a reliable way to reinstate damaged cells or grow new organs in humans. These stem cells – called Stimulus-Triggered Acquisition of Pluripotency cells (STAP cells) were able to differentiate and mature into different types of cells and tissues upon embryonic microinjection results. However, some figures in one of the papers published in Nature might be taken from Obokata’s doctoral dissertation, which was on different experiments, and that another image seemed to be artificially modified deliberately. On the other hand, some scientists have been unable to replicate the research’s results.

Recently, one of the scientist on the research team who was also one of the authors, Teruhiko Wakayama from the University of Yamanashi, has already called for the papers to be withdrawn. But a final decision would hinge on an agreement of all the authors and the journal itself.

Ref.

1.H. Obokata et al., Bidirectional developmental potential in reprogrammed cells with acquired pluripotency. Nature 505, 676 (Jan 30, 2014).

2.H. Obokata et al., Stimulus-triggered fate conversion of somatic cells into pluripotency. Nature 505, 641 (Jan 30, 2014).

Numerologist Warda is hooked on OG-L002 fishing, collecting. And lastly her encouragement comes from socializing along with her companions.