The Effects of Genistein, Thymoquinone, Epigallocatechin-3-gallate,5-Fluorouracil, and Low Level Laser Therapy on FaDu Hypopharyngeal and Laryngeal Carcinoma Cells

摘要

Laryngeal and hypopharyngeal carcinoma are two types of head and neck squamous cell carcinomas. The location of the tumor makes it hard to detect without complex tests. Overall, these types of cancer are not common, and there are no simple screening tests for such cancers. Due to this issue, laryngeal and hypopharyngeal carcinoma are usually diagnosed when signs and symptoms occur, such as sore throat, trouble swallowing, and constant coughing. With the use of FaDu, a head and neck cancer cell line of the hypopharyngeal origin, experimentation can be performed in order to initiate possible treatments. The standard treatments for laryngeal and hypopharyngeal carcinoma include conventional chemotherapy, such as 5-fluorouracil and cisplatin, chemo- radiation, and surgery. The treatments used in this experiment include 5-Fluorouracil (5-FU), Genistein (G), Thymoquinone (TQ), Epigallocatechin-3-gallate (EGCG), and low level laser therapy (LLLT). 5-FU is one of the most commonly used drugs to treat several cancers, including head and neck cancers. G is an isoflavone metabolite of soy generated by gut floral bacteria and has been characterized as a possible prevention for cancer. TQ is an ingredient isolated from Nigella sativa and has been investigated for its anti-oxidant, anti-inflammatory, and anticancer activities in both in vitro and in vivo models. EGCG, one of the main flavonoids found in green tea, is considered as one of the most active molecules known for its anti-oxidant properties. LLLT may enhance or decrease cell proliferation. LLLT has shown to induce apoptosis in cancer such as a human colon carcinoma cell line by increasing reactive oxygen species (Saenko et al 2016). udThe goals of this experiment were to investigate the effects of LLLT on FaDu cells and to determine the effects of natural products such as G, TQ, and EGCG, as chemotherapeutic agents, and 5-FU (a conventional chemotherapeutic agent), combined with LLLT, on FaDu cells. Specifically, cells were treated with LLLT, TQ, G, EGCG, or 5-FU; or LLLT plus TQ, G, EGCG, or 5-FU. The cells were then harvested and cellular protein, intracellular glutathione levels, nitric oxide levels, and lactate dehydrogenase levels were evaluated. Due to the low level of anti-cancer efficacy, G was discontinued. The results show a significant decrease in protein levels and cell numbers following treatment with TQ, however, this trend was inconsistent throughout the study. There was a significant increase in nitric oxide and LDH levels following treatment with EGCG and EGCG + laser, and this trend remained consistent throughout the study. However, since EGCG displayed similar results as EGCG + laser, LLLT possibly does not have any additional effect when combined to EGCG. Overall, LLLT did not show significant effect on FaDu cells. EGCG alone was shown to be the most effective treatment, in terms of inducing the most cellular damage and toxicity in the cancer cells. ud