Single injection may revolutionize melanoma treatment, Moffitt study shows

A new study at Moffitt Cancer Center could offer hope to people with melanoma, the deadliest form of skin cancer. Researchers are investigating whether an injectable known as PV-10 can shrink tumors and reduce the spread of cancer. PV-10 is a solution developed from Rose Bengal, a water-soluble dye commonly used to stain damaged cells in the eye. Early clinical trials show PV-10 can boost immune response in melanoma tumors, as well as the blood stream.

"Various injection therapies for melanoma have been examined over the past 40 years, but few have shown the promising results we are seeing with PV-10," said Shari Pilon-Thomas, Ph.D., assistant member of Moffitt's Immunology Program.

In the initial study, researchers injected a single dose of PV-10 into mice with melanoma. The result was a significant reduction in the skin cancer lesions, as well as a sizable reduction in melanoma tumors that had spread to the lungs. The researchers said the dye solution appeared to produce a robust anti-tumor immune response and may be safer than existing immunological agents.

"We are currently in the middle of our first human clinical trial of PV-10 for advanced melanoma patients. In addition to monitoring the response of injected melanoma tumors, we are also measuring the boost in the anti-tumor immune cells of patients after injection," explained Amod A. Sarnaik, M.D., assistant member of Moffitt's Cutaneous Oncology Program.

The initial study appears in PLOS ONE, an open-access, peer-reviewed online journal. It was supported by a sponsored research agreement with Provectus Pharmaceuticals, Inc., developer of PV-10.

About Moffitt Cancer Center

The most dangerous form of skin cancer, these cancerous growths develop when unrepaired DNA damage to skin cells (most often caused by ultraviolet radiation from sunshine or tanning beds) triggers mutations (genetic defects) that lead the skin cells to multiply rapidly and form malignant tumors. These tumors originate in the pigment-producing melanocytes in the basal layer of the epidermis. Melanomas often resemble moles; some develop from moles. The majority of melanomas are black or brown, but they can also be skin-colored, pink, red, purple, blue or white. Melanoma is caused mainly by intense, occasional UV exposure (frequently leading to sunburn), especially in those who are genetically predisposed to the disease. Melanoma kills an estimated 8,790 people in the US annually.

If melanoma is recognized and treated early, it is almost always curable, but if it is not, the cancer can advance and spread to other parts of the body, where it becomes hard to treat and can be fatal. While it is not the most common of the skin cancers, it causes the most deaths. The American Cancer Society estimates that at present, about 120,000 new cases of melanoma in the US are diagnosed in a year. In 2010, about 68,130 of these were invasive melanomas, with about 38,870 in males and 29,260 in women.