Cancer Stem Cells Flashcards
What are iPS cells
Somatic cells induced to be a stem cell
How in an experiment iPS cells were used in the treatment of sickle cell disease
In a mouse with sickle cell disease, fibroblast were extracted from the tail, they were reprogrammed to iPSCs, correct gene was introduced in these cells for beta globulins in the Hb, the existing gene was knocked out, these iPSCs were then differentiated into hematopoietic stem cells and then introduced into the mouse, the mouse was cured of sickle cell disease
What was the example that he gave of the heart
Basically they made a tinee tiny human heart with all the cardiac muscles, smooth muscles and connective tissue
What was the example that he gave of the heart
Basically they made a tinee tiny human heart with all the cardiac muscles, smooth muscles and connective tissue
What are the drawbacks of using iPSCs in treatment as compared to fresh gametes that can fuse and lead to the give us a zygote
iPSCs will have all the epigenetic markers (DNA methylation and histone modifications) as well as all the mutations that the somatic cell had. It basically carries all the information that a person has been exposed to. Fusion of gametes resets all the epigenetic markers and it also doesn’t involve a lot of mutations since those are repaired before cell division
Can you make a neuron cell from a fibroblast directly without going back to the stem cell?
YES. By introducing the right factors
Different ways you can obtain different form of stem cell
What are the top ten factors to consider for a patient before opting for stem cell therapy
- There are different types of stem cell each with their own purpose 2. A single stem cell treatment doesnt work for diseases that are complex and involves a range of different kinds of cells 3. Currently many stem cell therapies are controversial, few are widely accepted 4. Just because people say stem cell helped them doesnt mean the therapy really worked 5. It is a complicated and difficult process that is still not completely understood 6. Stem cells have to instructed to take specific pathways in treatment 7. If a stem cell comes from your body doesnt mean that it is safe 8. There is something to lose when trying an unproven treatment 9. An experimental treatment offered for sale is not the same thing as clinical trial 10. Stem cell science is still evolving
How can you avoid passing on genetic diseases in the family? Explain the process.
By performing the process called Preimplantation Genetic Diagnosing (PGD). This is done by taking out a single cell from the zygote when it is at the 8 cell stage. Only those zygote that dont have the disease are planted on the mothers. At this stage other factors such as sex of the baby or if they will form twins or not cannot be determined
What is another form through which oncogenic risks are associated with pluripotency
There are oncogenic risk associated with the manner in which we induce pluripotency, hence the methods matters.
What is the main risk associated with cancer stem cells
Some of the cancer stem cells have different sensitivities to radiation and chemotherapy. Also cancer stem cells are quiescent, they are not replicating that often, so if we dont kill all of these cells or miss them, the tumor can arise again
What is the difference in solid and liquid tumors
It literally means if the tumor cells are in a solid or liquid form. For example cancers of the blood are liquid tumors.
What are the chances of tumor from stem cells
Chances are very small but it can still happen
What is the primary difference in solid and liquid tumors from cancer stem cells
For solid tumors, very large number of cancer stem cells are required, often a significant part of the stem cell colony, hence the chances of that happening are small
What are the 2 models of cancer heterogeneity in cancer stem cells
- Stochastic model: All stem cells can be potential cancer cells however they only have a small probability of proliferation autonomously to contribute to the development of neoplasm 2. Cancer stem cell model: Only a small number of cells in the colony of stem cells have the ability to contribute to neoplasms - this one is in the lead - combination of genetic and epigenetic changes along the proliferation pathway can give rise to a specific cancer stem cell, this has been proved in an assay See the attached slide below
How do you treat cancer stem cells
This is explained here in the slide below. In conventional therapy we treat the whole mass of cancer cells by chemotherapy and radiation which causes the tumor to shrink and eventually die off. However this does not work for cancer stem cells. The way to treat cancer stem cells is to target the chemotherapy and radiation to the cancer stem cells themselves. By killing off these cells, the tumor loses its reproductive potential and dies off. You can also knock out the transcriptional factors that have caused the stem cells to become cancer stem cells. This will also cause the cancer to die off
What is he trying to explain
Attacking the specific transcription factors of cancer stem cells can be used to kill off the cancer
Summary slide
