INPLASY202670066 Cytotoxicity of Bitter Compounds on Nasopharyngeal Carcinoma: A Systematic Review and Meta-Analysis of In Vitro Studies Keywords: Nasopharyngeal carcinoma; Bitter compounds; Cytoto…

Field cancerization in the upper respiratory tract (URT) heavily drives cancer recurrence. The present study evaluated Thai ethnobotanical ingredients from Kampramong’s anticancer remedies as alternative agents for URT cancer control. Thirty-one ethanolic extracts were screened for cytotoxicity against six URT malignant cell lines (HK1, KB, HONE-1, NPC38, NPC43, and HEp2) and two non-cancerous controls (NP460 and HaCaT) using the sulforhodamine B (SRB) assay. The selectivity index or IC₅₀ ratio of normal cells/cancer cells was also determined for selective cytotoxicity of extracts and compounds. Anti-inflammatory activity was measured using the nitric oxide (NO) reduction assay. Antioxidant capacity was measured using the DPPH radical scavenging assay. Total flavonoid content (TFC) was measured due to the main risk reduction factor. Multivariate analyses (Hierarchical Cluster Analysis; HCA and Principal Component Analysis; PCA) were used for the relationship of flavonoids, NO inhibition drive to cytotoxicity. The best plant extracts and their cytotoxic compounds were also predicted to have their target molecular mechanisms by molecular docking. HCA identified Caesalpinia sappan, Coscinium fenestratum, and Tectona grandis as exhibiting potent cytotoxicity against all malignant cells, with C. sappan being the most potent. PCA revealed that flavonoid content and nitric oxide inhibition were the critical factors driving cytotoxicity (factor load 71.93%). Molecular docking of C. sappan compounds, brazilin and sappanchalcone, showed high binding energies with multiple core target proteins (MAPK1, MAPK3, SRC, AKT1, and GRB2), indicating a synergistic multi-compound, multi-target mechanism, representing a hypothesis for future mechanistic validation. Kampramong’s ethnobotanical remedies, particularly C. sappan, are promising candidates for URT malignancy treatment and field cancerization prevention, offering valuable data for future drug development.