Targeting Melanoma Tumors with Polyclonal Antibodies

There are many types of skin cancers, but the most serious is often considered to be melanoma. It develops in the melanocytes, which produce melanin in the skin. Melanoma can form in the eyes and inside the body, but occurrences inside the body are rare. Damage occurs to the DNA in melanocytes, causing these cells to multiply without control and ultimately form a mass of cancerous cells. The exact cause of melanoma is unclear — most likely a combination of genetic and environmental factors. Though a cause has remained unidentified, that does not prevent melanoma from being a serious illness that warrants action from the research community. 

Melanoma Symptoms and Effects

People typically respond well to treatment if melanoma is detected and diagnosed early. However, if a diagnosis is missed, cancer can easily spread to other parts of the body. Early signs of melanoma are changes to an existing mole or the development of a new or unusual growth on the skin. These growths may be dark if the cancerous cells are still producing melanin, but they can also be tan, pink, or white if they are not producing melanin. Melanoma growths can be irregularly shaped, larger than a quarter of an inch, and may bleed. While these symptoms may seem small and insignificant, the growth can signal Stage 1 of a cancer diagnosis. 

       Melanoma Stages

• Stage 1 – This stage has two conditions: 

1. 1A is the presence of a cancerous tumor of less than 1 mm in size with no ulceration.
2. 1B is the presence of a cancerous tumor of less than 1 mm with ulceration or a tumor between 1-2 mm with no ulceration. 

• Stage 2 – This stage has three conditions:

1. 2A is a 1-2 mm tumor with ulceration or 2-4 mm in size without ulceration. 
2. 2B is an ulcerated tumor between 2-4 mm or a tumor greater than 4 mm in size without ulceration. 
3. 2C is a tumor over 4 mm with ulceration.

• Stage 3 – In addition to a tumor of any size that may or may not have ulceration, there must also be multiple tumors or cancer cells found at least 2 mm from each other. Cancer may also be found in lymph nodes.

• Stage 4 – Cancer has spread to distant sites, including soft tissue, bone, and organs.

As mentioned, melanoma begins small but can quickly spread to other sites on or in the body. As cancerous cells spread, survival rates dramatically decrease. If caught early and localized, the survival rate is 99%. Alternatively, Stage 4 or distant melanoma metastasis only has a 27% survival rate. 

Treatment of Melanoma

Treatment of melanoma depends on the size and stage of the cancer, personal preferences, and the patient’s overall health. Surgery to remove cancerous tissue may be the only required treatment for early-stage melanomas. However, melanomas that have spread beyond the skin require additional treatment. 

A common and effective cancer treatment is chemotherapy; however, this treatment has many adverse side effects. They can include neuropathy, a weakened immune system, nausea, vomiting, breathing problems, and pain in different areas of the body. These reactions are a driving force behind finding alternate treatment routes for cancer patients. 

Polyclonal Antibodies to Target Melanoma Tumors

Recently, researchers have uncovered a development in melanoma treatment with polyclonal antibodies. Polyclonal antibodies contain a complex, heterogeneous mixture of antibodies that recognize the same protein. The combination of different antibodies has eliminated the issue of tumor heterogeneity resulting in tumor regrowth when there is only a single target. Polyclonal antibodies targeting many mutated tumor proteins inhibit tumor growth and prolong survival. This method of melanoma treatment is currently undergoing an FDA-approved phase I trial in cancer patients and offers great hope for future treatment opportunities.