Eukaryotic DNA is organized differently than prokaryotes, containing multiple chromosomes made of linear DNA molecules packaged around histone proteins to form chromatin. The cell cycle regulates cell division, ensuring daughter cells receive a full copy of the genome through DNA replication and cell growth or repair. Researchers found inhibiting signaling pathways in brain cancer cells stopped their reproduction and migration, making them more sensitive to chemotherapy. Studying chromatin remodeling genes in pancreatic cancer showed restoring expression of missing genes slowed cancer cell growth and induced senescence.

1. BY: MARIA FERNANDA URIBE 3RD SEMESTER - UPB

4. Eukaryotic DNA is organized differently from Prokaryotes. Eukaryotic genome is composed of multiple chromosomes consisting of linear DNA molecules. DNA is normally packaged tightly around bundles of protein called histones, and the combination of DNA and proteins is called chromatin. A characteristic of cells is their capacity of self-reproduction. The cell division generates two daughter cells with the same genetic material of the origin one. This division is regulated and coordinated with cell growth and DNA replication, to ensure the formation of daughter cells containing their complete genomes. Cell cycle has two different phases: interphase (G0 phase, G1 phase, S phase, G2 phase) and mitosis (prophase, metaphase, anaphase, telophase). The cycle is controlled by different proteins that are always there to guarantee the right process of division, if not the DNA replicates damaged. There are different points in which the DNA can be repaired. If the gene coding for any of these proteins is mutated or deleted pathology can appears, usually cancers, because DNA replicates and passes on to daughter cells without reparation.

5. Brain cancer is hard to treat. Researchers of the University of Colorado Cancer Center show how to stop cells of brain cancer from reproducing and migrating, being the last one the major problem. ScienceDaily (Jan. 18, 2012)

6. They say that turning off TAM family signaling make cancer cells less robust, but did not know what other problems could be caused.

7. Inhibiting Axl family member at least stopped cancer cell migration. When they inhibited Mer pathway, cancer cells became more sensitive to chemotherapy and could not escape to safer areas.

8. Now the researchers are currently testing the technology in mice, after which all involved hope to move soon to human clinical trials.

9. It helps to make chemotherapy more effective, and people with this pathology would accept this treatment rapidly. So, science would be more capable to help them. In addition to this, discovering one of the forms of making the pathology less intelligent, helps us to know what other experiments could be done.

10. Technological advances show that at least one subunit of the SWI/SNF protein complex is deleted, mutated or rearranged in patients with pancreatic cancer. ScienceDaily (Jan. 9, 2012)

11. Researchers at the Stanford University School of Medicine experimented with artificially increasing the expression of the gene for one of the subunits and found that restoring the expression of one of the missing genes slowed the growth of pancreatic cancer cells and even began to senesce, or enter a permanently arrested state, rather than dividing uncontrollably.

12. SWI/SNF works by repositioning histones on DNA to make it available for the transcription factors that govern DNA´s use as a template for the synthesis of RNA.

13. The researchers are now working to pinpoint exactly which genes are important to drive the growth of human pancreatic cells by artificially overexpressing or blocking the expression of genes coding for various SWI/SNF subunits.

14. Is very important to know all the mechanisms in which cancer acts. This one can be used to help preventing this pathology and give us a clue to start investigating how else can these genes perform.

15. Turning off a family of signals not only makes brain cancer cells less robust, but also more sensitive to chemotherapy and unable to escape to safer areas of the brain, which represents a new targeted therapy nobody tried before.

16. A new family signaling could be discovered and how its family members affect not only proliferation but migration.

17. After the investigation the researchers can be sure that chromatin modification and remodeling play an important role in cancer and that the major effect is likely to be through changes in the expression of genes.

18. The researchers could identify new genes involved in pancreatic cancer. It really validates the use os genome-wide analysis.

19. http://medicalpicturesinfo.com/brain-cancer/ MARTINEZ SANCHEZ, Lina Maria. Biologia molecular. 6 ed. 2011. Medellin: UPB. Fac de Medicina. COOPER, Geoffrey M. La celula. Editorial Marban, 2 ed, 2002..

20. THANKS