Enhancing docetaxel efficacy in prostate cancer: the synergistic role of <i>thymus vulgaris</i> extract in inducing apoptosis and autophagy

Prostate cancer (PC) is a common malignancy in men, and resistance to treatment in advanced stages remains a significant clinical problem. Docetaxel (DTX) is widely used in advanced PC therapy; however, its efficacy can be limited by toxicity and acquired resistance. Therefore, plant-derived compounds are being explored as supportive therapeutic agents. This study investigated the cytotoxic and antiproliferative effects of <i>Thymus vulgaris</i> (<i>T. vulgaris</i>) extract on PC-3 prostate cancer cells, both alone and in combination with DTX. PC-3 cells were treated with varying concentrations of <i>T. vulgaris</i> and DTX individually and in combination. Cell viability was measured using the MTT assay, and proliferative activity was assessed by AgNOR staining. Cell cycle distribution was analyzed using a Muse cell analyzer, apoptosis was detected via the TUNEL assay, and autophagy-associated protein expression (LC3 and p62) was examined immunohistochemically. <i>T. vulgaris</i> extract exhibited dose-dependent cytotoxicity with an IC⁵⁰ of 8 μg/mL. The combined treatment with <i>T. vulgaris</i> and DTX resulted in greater inhibition of cell viability, significant G0/G1 cell cycle arrest, increased apoptosis, and enhanced autophagy. Additionally, AgNOR analysis indicated reduced proliferative capacity. These findings suggest that <i>T. vulgaris</i> may enhance DTX efficacy and serve as a promising natural adjuvant in PC therapy.