what are the fundamental changes in normal cell cycle and function compared with myeloma cell?

Answer 1

All cancer cells have multiple abnormalities in the cell cycle which contributes to the process of carcinogenesis. Almost all cancers (e.g. myeloma) have multiple Oncogenes (tumor promoter genes) and dysfunction of Tumor Suppressor genes.

Oncogenes function like 'gas pedals' that accelerate the cell cycle too fast for proper DNA repair. Tumor Suppressor Genes are inhibited in cancer cells. These genes normally act as 'brakes' to slow down the cell cycle to give more time for DNA repair.

When DNA repair is not effective, the cell procedes to divide itself via mitosis. Mitosis with damaged DNA can result in production of mutations that create more Oncogenes or inhibit more Tumor Suppressor genes. The net result, is an increasing process of genetic damage and tumor promotion - this is known as Genetic Instability.

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