Current Molecular Concepts Of Oral Carcinogenesis And Invasion

Oral carcinoma or oral cancer (OC) is known to be the most common type of cancer found in South East Asian regions. Reports state that approximately around 20% to 30% suffer from this oral disease with a whopping sixth place in the most common malignancy that causes morbidity and high rate of mortality worldwide.
* Cellular & Molecular Hallmarks of Cancer
In general, oral carcinoma managed to emerge from accumulating genetic variations and abnormality in the epigenesist of the signaling pathways which are associated with that cancer, thus resulting in phenotypic facilitation and changes of the oral carcinoma cells.
Oral carcinoma is known to be a malignant neoplasm which originates from the lining epithelium known as stratified squamous epithelium of the oral mucosa layer. The malignant neoplasm of oral cancer can be seen to occur most commonly in on the lips, lateral sides of the tongue (affected papillae such as the fungiform, and foliate papillae) and affected individuals usually obtain this disease with increase in age, usually occurring for patients 40 or above 40 years old; however, there are several other causes of oral which are multifactorial in nature and some are:
* Cigarette smoking (1st hand and 2nd hand smoking)
* Alcoholism
* Human Papilloma Virus
* Excessive sun exposure to mouth or lips
* Weak immunization/immune system
On a molecular level, OC evolves initially from a cell injury to form the malignant neoplasm. On a micro anatomical level, the lesion (malignant neoplasm) will undergo various phases with regards to the pre-neoplastic damage up until the formation of cancer itself. Some associated disease to OC include leukoplakia, erythroplakia, and mixed which will eventually trigger cancer since they serve as precancerous lesions.
* Proto-oncogenes, oncogenes, and oncoproteins
Proto-oncogenes are generally associated with cancer cells. They code for proteins which in turn helps with the regulation of many of the normal cells. Proto-oncogenes will play a role in dominant positive regulation of cell growth and differentiation. Due to OC, proto-oncogenes are altered and this gene is now called oncogene. Oncogene is known to cause mutation of genes, amplification of unwanted genes (mutated genes), and the over expression of these modified genes. To maintain homeostasis, regulation of all signal cells and/or pathways is needed to maintain normal cell growth and avoid disturbance in to not cause neoplasia.
By definition, oncoprotein is an encoded protein by an oncogene which causes the transformation of a normal cell into a tumor cell once it is exposed to it.
* Self-sufficiency in Growth Signals
Biomarkers are used to check for the sufficiency of cell growth in oral carcinoma. These biomarkers also help in the growth of carcinoma cells during signaling.
Some markers include p53 which also acts a tumor suppressor gene and generally contributes to the wide variation of adenocarcinoma. Alongside p53 is Ki-67 wherein it also acts as indicators for cell proliferation. Since both are mutated genes, they can act and report the amount of carcinoma cells growing and p53 specifically will protect the body against tumor formatio...