Cancer cells are cells gone wrong -- in other words, they no longer react to several of the signals that control cellular growth and death. Cancer cells arise in tissues and, as they grow and divide, they diverge ever further from normalcy. With time, these cells become more and more resistant to the controls which maintain normal tissue -- and consequently, they divide faster than their progenitors and become less dependent on signals from other cells. Cancer cells evade programmed cell death, in spite of the fact that their multiple abnormalities could normally cause them prime targets for apoptosis. At the late stages of cancer, cells burst through normal tissue boundaries and metastasize (spread) to fresh sites in the body.

In ordinary cells, hundreds of genes Intricately control the method of cell division. Regular growth takes a balance between the activity of those genes which promote cell regeneration and the ones that suppress it. In addition, it relies upon the activities of genes that indicate when damaged cells ought to undergo apoptosis.

After mutations collect in the various genes which control cell proliferation. Based on study findings from the Cancer Genome Project, most cancer cells have 60 or more mutations. The challenge for medical researchers would be to recognize which of those mutations are responsible for certain kinds of cancer. This practice is similar to hunting for the proverbial needle in a haystack, because lots of the mutations within those cells possess little to nothing to do with cancer growth.
Different kinds of cancers have distinct mutational signatures. However, scientific comparison of numerous tumor types has revealed that certain genes are mutated in cancer cells more frequently than others. For instance, growth-promoting genes, like the gene for the signaling protein Ras, are among those most commonly found in cancer cells, becoming super-active and generating cells which are too closely stimulated by development receptors. Some chemotherapy drugs work to counteract those mutations by blocking the action of growth-signaling proteins. The breast cancer medication HERCEPTIN, as an instance, blocks overactive receptor tyrosine kinases (RTKs), and the drug Gleevec blocks a cortical signaling kinase associated with chronic myelogenous leukemia.

Other cancer-related mutations inactivate the genes that Curb cell proliferation or those that indicate the need for apoptosis. These Genes, called tumour suppressor gene , Normally function like brakes on proliferation, and the two copies inside a cell must be mutated in order for uncontrolled branch to occur. For instance, many cancer cells take two mutant copies of this gene that codes for p53, a multifunctional protein that generally senses DNA damage

STAGES OF CANCER

Throughout the early stages of cancer, tumors are typically benign and stay restricted within the normal boundaries of a tissue. As tumors grow and become cancerous i.e.malignant, however, they get the ability to break through those boundaries and invade adjacent cells.

Invasive cancer cells often secrete proteases which permit them to degrade the extracellular matrix in a tissue's boundary. Proteases also give cancer cells that the capacity to make new passageways in cells. For example, they could break down the junctions that combine cells together, thereby gaining access to new lands.

# METASTASIS
Metastasis -- actually meaning "new location" -- is among those terminal stages of cancer. Within this phase, cancerous cells enter the bloodstream or the lymphatic system and go to some other place within the body, in which they start to split and lay the basis for secondary tumors. Not many cancer cells can metastasize. To be able to spread this manner, the cells have to be able to permeate the standard obstacles of the body in order they could both enter and depart the lymph or blood vessels. Even travel metastatic cancer cells confront difficulties when seeking to grow in new areas.

# SYMPTOMS
• fatigue,
• weight loss,
• pain,
• skin changes,
• change in bowel,
• unusual bleeding,
• persistent cough,
• fever,
• tissue masses.

# CANCER TREATMENTS
There are various varieties of cancer therapy. The kinds of therapy which you have will be based on the kind of cancer you've got and how complex it is. Some individuals with cancer will have just one treatment.

· operation with radiation or chemotherapy treatment

· immunotherapy,

· targeted treatment,

· hormone treatment.