Effects of Low-Dose Naltrexone on Oral Squamous Cell Carcinoma Cells

Objectives: Oral Squamous Cell Carcinoma (OSCC) is one of the most common malignancies affecting the oral cavity worldwide, with a poor survival rate due to disease invasion and metastasis. Naltrexone (NTX), a drug primarily used to manage opioid use disorder, has shown potential efficacy in low doses (LDN) when administered intermittently in reducing ovarian cancer cell growth. This study aimed to determine if LDN has similar anti-cancer effects on OSCC.
Methods: This study tested SCC-25 (human OSCC cell line), Detroit 562 (human metastatic pharyngeal carcinoma cell line), and SKOV-3 (human ovarian cancer cell line). Cells were treated with LDN at varying concentrations (1-100µM) and intervals (constant exposure, 5 hours once, 5 hours daily, or 5 hours every other day). Cell viability was assessed at 72 hours following initial drug treatment, using sulforhodamine B (SRB) assays. Opioid Growth Factor Receptor (OGFr) expression was analyzed via Western blot.
Results: Both OSCC and Detroit 562 expressed OGFr, indicating potential inhibition of tumor cell proliferation. However, no significant or consistent effect of LDN on OSCC cell growth was observed across the trials. Comparisons to SKOV-3 cells confirmed similar outcomes, showing limited LDN efficacy, but with a trend toward growth inhibition with intermittent LDN.
Conclusions: LDN does not significantly affect OSCC cell growth at therapeutic dosages when used alone. Further research may be needed to explore combination therapies to enhance its potential anti-cancer effects.