cancer

Examples of cancer in the following topics:

• Epigenetic Alterations in Cancer

  • Cancer epigenetics is the study of epigenetic modifications to the genome of cancer cells that do not involve a change in the nucleotide sequence.
  • Epigenetic alterations are as important as genetic mutations in a cell's transformation to cancer.
  • Increasingly, scientists are understanding how these epigenetic changes are altered in cancer.
  • In cancer cells, silencing genes through epigenetic mechanisms is a common occurrence.
  • Describe the role played by epigenetic alterations to gene expression in the development of cancer

• Cancer and Translational Control

  • There are many examples of translational or post-translational modifications of proteins that arise in cancer.
  • An example of how the expression of an alternative form of a protein can have dramatically different outcomes is seen in colon cancer cells.
  • However, in colon cancer cells, expression of the long form results in increased cell growth instead of cell death.
  • Clearly, the expression of the wrong protein dramatically alters cell function and contributes to the development of cancer.
  • Undoubtedly, more targeted therapies will be developed as scientists learn more about how gene expression changes can cause cancer .

• Cancer and Post-Transcriptional Control

  • Changes in the post-transcriptional control of a gene can result in cancer.
  • Several studies have demonstrated a change in the miRNA population in specific cancer types.
  • It appears that the subset of miRNAs expressed in breast cancer cells is quite different from the subset expressed in lung cancer cells or even from normal breast cells.
  • It would, therefore, be conceivable that new drugs that turn off miRNA expression in cancer could be an effective method to treat cancer.
  • Specific types of miRNAs are only found in cancer cells.

• Cancer Proteomics

  • Some examples of protein biomarkers used in cancer detection are CA-125 for ovarian cancer and PSA for prostate cancer.
  • The National Cancer Institute has developed programs to improve the detection and treatment of cancer.
  • The Clinical Proteomic Technologies for Cancer and the Early Detection Research Network are efforts to identify protein signatures specific to different types of cancers.
  • In cancer research and medicine, biomarkers are used in three primary ways: (A) Diagnostic - To help diagnose conditions, as in the case of identifying early stage cancers.
  • Explain the ways in which cancer proteomics may lead to better treatments

• Altered Gene Expression in Cancer

  • Cancer, a disease of altered gene expression, is the result of gene mutations or dramatic changes in gene regulation.
  • Cancer can be described as a disease of altered gene expression.
  • While these changes do not occur simultaneously in one cancer, changes at each of these levels can be detected when observing cancer at different sites in different individuals.
  • When mutated, proto-oncogenes can become oncogenes and cause cancer .
  • An example of an oncogene involved in cancer is a protein called myc.

• Cancer and Transcriptional Control

  • Alterations in cells that give rise to cancer can affect the transcriptional control of gene expression.
  • This could also lead to the increased transcription and aberrant gene expression that is seen in cancer cells.
  • Researchers have been investigating how to control the transcriptional activation of gene expression in cancer.
  • In breast cancer, for example, many proteins are overexpressed.
  • New drugs that prevent the activation of EGFR have been developed and are used to treat these cancers.

• Cell Signaling and Cell Growth

  • Cancer biologists study the molecular origins of cancer with the goal of developing new prevention methods and treatment strategies that will inhibit the growth of tumors without harming the normal cells of the body.
  • This prevents the cell from regulating its cell cycle, triggering unrestricted cell division and cancer.
  • The genes that regulate the signaling proteins are one type of oncogene: a gene that has the potential to cause cancer.
  • Cancer biologists have been able to identify many other oncogenes that contribute to the development of cancer.
  • Cancer biologists realized that gene duplication led to HER2 overexpression in 25 percent of breast cancer patients and developed a drug called Herceptin (trastuzumab), a monoclonal antibody that targets HER2 for removal by the immune system.

• Predicting Disease Risk at the Individual Level

  • He was also predicted to have a 23 percent risk of developing prostate cancer and a 1.4 percent risk of developing Alzheimer's.
  • Their recommendation was based on evidence that screening does not reduce the risk of death from prostate cancer.
  • Prostate cancer often develops very slowly and does not cause problems, while the cancer treatment can have severe side effects.
  • PCA3 is a gene that is expressed in prostate epithelial cells and overexpressed in cancerous cells.
  • A high concentration of PCA3 in urine is indicative of prostate cancer.

• Proto-oncogenes

  • Proto-oncogenes normally regulate cell division, but can be changed into oncogenes through mutation, which may cause cancers to form.
  • Proto-oncogenes are normal genes that, when mutated in certain ways, become oncogenes: genes that cause a cell to become cancerous.

• Genomics and Proteomics

  • For example, the protein content of a cancerous cell is often different from that of a healthy cell.
  • Certain proteins in the cancerous cell may not be present in the healthy cell, making these unique proteins good targets for anti-cancer drugs.
  • This machine is preparing to do a proteomic pattern analysis to identify specific cancers so that an accurate cancer prognosis can be made.