7.7 Cancer Therapy and Alternative Genetic Therapy Flashcards
What are the most common treatments for cancers?
chemotherapy
radiation therapy
What is the basic mechanism of chemotherapy and radiation therapy?
preferentially target quickly growing cancer cells
What is the function of antihormone treatments for genitcal cancers?
block hormone dependent signaling pathways that tumors rely on
What is the general function of most chemotherapies?
bind to DNA and RNA to interfere with replication and transcription
What is the general function of radiation therapy?
inducing DNA single stranded and double stranded breaks leading to cell death
What are the main radiation therapies?
X-rays
Gamma-rays
neutron beams
Why do cancer treatments have a lot of side effects?
they also damage normal cells in the process
What healthy cells do chemotherapies typically attack and why?
epithelial, immune system, and Gi tract cells because chemotherapy targets quickly dividing cells
What are suicide genes?
genes that insert specifically into cancer cells to cause self-destruction
What is the purpose of trying to use genes that regulate angiogenesis as gene therapies?
cancer cells have a profound blood supply and genes that could disrupt angiogenesis could starve cancer cells
What is the biggest conundrum of gene therapy?
how to deliver it
How has gene therapy been delivered to a patient?
using a virus vector
What is controversial about gene therapy?
it is irreversible
What is epigenetics?
study of mechanisms that cause modifications to gene expressions that do not depend on the changes in the DNA sequence
What is the epigenome?
any epigenetic modifications to the genome that are present in a cell at any given time
What does it mean that cancer cells are marked by a global hypomethylation of genes?
there is a lack of methylation meaning there is genomic instability and underlying chromosomal changes
What does hypermethylation in some cancer genes cause?
inactivates certain genes
What is a common modification in cancer cells?
change in the pattern of chromatin remodelling
What is a result of histone acetylation in cancer cells?
reduction in the ability of a histone to associate with DNA allowing the transcription of gene products
What is a result of histone deactylation in cancer cells?
histones are able to associate with DNA causing some genes to not be transcribed
