Cancer is an uncontrolled growth of cells. It is responsible for 13% of deaths worldwide (an estimated 7.7 million deaths in 2007). Cancer results from mutation in genes controlling cell growth, differentiation and death. Uncontrolled growth is a character of cancer and of benign neoplasms. Anaplasia, invasion and metastasis sets cancer apart from a benign tumour. Cancer is lethal because of it's ability to metastasize. Metastasis kill 90% of cancer patients.

The genes causing cancer
Why should the human genome have genes capable of causing cancer? Were it not for these genes a zygote would not develop into a foetus. Normal development depends on an adequate number and appropriate type of cells populating each developing organ. Cell division, tissue invasion, migration of these cells to sites distant from the origin and loss of unwanted cells are necessary for normal embryonic development. These process are very precise. This is evident from the extremely low levels of conginital anomalies. Cancer results when these processes get derranged.

Cancer causing genes fall into two categories, oncogenes and tumour supressor genes. About 1% of the genome (over 200 genes) are involved in malignant transformation. Some commonly mutated cancer genes and their normal function are listed below (oncogenes in blue, tumour suppressor genes in red).

1. Growth Factors
   
   1. PDGFB: Platelet Derived growth factor beta.
      
2. Receptors
   
   1. EGFR, ERBB2: Epithelial growth factor receptors
      
   2. PDGFA, PDGFB: Platelet derived growth factor receptors
      
   3. FLT1, KDR, FLT4: Vascular endothelial growth factor receptor
      
3. Signal Transduction
   
   1. Small G Proteins: HRAS, KRAS, NRAS
      
   2. MAPK/ERK Pathway: RAF1
      
   3. JAK/STAT: JAK2, STAT5A/B
      
   4. Hedgehog Pathway:PTCH1, SMO, SUFU
      
4. Transcription factors
   
   1. MYC
      
5. Genes involved in maintaining DNA integrity:
   
   1. Repair of double stranded DNA breaks: BRCA1, BRCA2
      
   2. Mismatch repair genes: MLH1, MSH2, MSH6, PMS1, PMS2
      
6. Cell cycle Regulators
   
   1. CCND1: Cycline D1 Gene
      
   2. RB1: Retinoblastoma tumour suppressor gene
      
7. Genes involved in apopotosis
   
   1. TP53:
      
8. Cytoskleton
   
   1. APC:
      
   2. NF2
      

What is Cancer?

Cancer is an uncontrolled growth of cells. It is responsible for 13% of deaths worldwide (an estimated 7.7 million deaths in 2007). Cancer results from mutation in genes controlling cell growth, differentiation and death. Uncontrolled growth is a character of cancer and of benign neoplasms. Anaplasia, invasion and metastasis sets cancer apart from a benign tumour. Cancer is lethal because of it's ability to metastasize. Metastasis kill 90% of cancer patients.

The genes causing cancer
Why should the human genome have genes capable of causing cancer? Were it not for these genes a zygote would not develop into a foetus. Normal development depends on an adequate number and appropriate type of cells populating each developing organ. Cell division, tissue invasion, migration of these cells to sites distant from the origin and loss of unwanted cells are necessary for normal embryonic development. These process are very precise. This is evident from the extremely low levels of conginital anomalies. Cancer results when these processes get derranged.

Cancer causing genes fall into two categories, oncogenes and tumour supressor genes. About 1% of the genome (over 200 genes) are involved in malignant transformation. Some commonly mutated cancer genes and their normal function are listed below (oncogenes in blue, tumour suppressor genes in red).

1. Growth Factors




1. PDGFB: Platelet Derived growth factor beta.




2. Receptors




1. EGFR, ERBB2: Epithelial growth factor receptors


2. PDGFA, PDGFB: Platelet derived growth factor receptors


3. FLT1, KDR, FLT4: Vascular endothelial growth factor receptor




3. Signal Transduction




1. Small G Proteins: HRAS, KRAS, NRAS


2. MAPK/ERK Pathway: RAF1


3. JAK/STAT: JAK2, STAT5A/B


4. Hedgehog Pathway:PTCH1, SMO, SUFU




4. Transcription factors




1. MYC




5. Genes involved in maintaining DNA integrity:
   




1. Repair of double stranded DNA breaks: BRCA1, BRCA2


2. Mismatch repair genes: MLH1, MSH2, MSH6, PMS1, PMS2




6. Cell cycle Regulators




1. CCND1: Cycline D1 Gene


2. RB1: Retinoblastoma tumour suppressor gene




7. Genes involved in apopotosis




1. TP53:




8. Cytoskleton




1. APC:


2. NF2:

The first post....

Contrary to popular perception, cancer is a common disease in developing countries. The incidence of cancer is lower. The populations are larger and the total number of cancer patients is more than the systems can cope up with. Cancer care is resource intensive. One of the most critical resource is trained manpower. Oncology remains underrepresented and obsolete in medical curricula in many parts of the world. The last few decades have seen an increase in the survival of cancer patients. This is not reflected in resource poor societies.

Cancer is a collection of more than 100 diseases. Some are curable even when disseminated, others are still incurable (see below; 5 year survival data for disseminated cancer the US SEER program 1988-2001). All cancers can not be measured by the same yardstick.

5 year survival of advanced cancer(Data from US SEER program 1998-2001)

The medical profession is nihilistic about cancer. Systemic therapy (chemotherapy, immunotherapy and targeted therapy) has improved survival of cancer patients. Refinement of surgery has reduced the mutilating effects of cancer treatment. Radiation techniques have improved. Everybody knows about the side effect of cancer therapy. Few know about it's benefits and fewer know that chemotherapy, the most dreaded form of cancer therapy, is slowly giving way to targeted therapy.

The attitudes towards cancer need to change. The change must start from the medical community!