الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
Nonmelanoma skin cancer (NMSC) is the most common type of
cancer. There are two primary types of non -melanoma skin cancer:
squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), and
they are both derived from the stratum basale of the epidermis. NMSC
is commonly found in populations with fair skin. In the United States,
NMSC incidence has increased with more than five million new cases
each year. Further, those with a history of skin cancer are at an
increased risk of developing other lethal types of cancer.
Basal cell carcinoma accounts for 80–85% of skin cancer and is
caused by intermittent UV exposure, particularly duringyouth. BCC
rarely invades other tissues and grows slowly.
Squamous cell carcinoma results from cumulative sun exposure
and makes up around 15 to 20% of all skin cancers .SCC is common
among those who work outdoors and are exposed to substantial UV
radiation. SCC most frequently occurs on areas of the body which are
most exposed to sunlight such as the face and head, and these cancers
are capable of metastasizing.
Oxidative stress plays an important role in the promotion and
prevention of carcinogenesis. Relatively high levels of reactive
molecules are required to activate proliferative and pro-survival signal
transduction pathways while excessive oxidative stress causes
sufficient damage to cellular DNA, proteins and lipids to activate cell
death pathways .Thus, a therapeutic strategy that has been employed
to elicit tumor cell death is to utilize agents that induce excessive
oxidative stress. Several clinically available anticancer agents, including doxorubicin and bleomycin, induce tumor cell death by
initiating lethal oxidative stress.