Oral cancer is one of the malignancies most closely associated with chronic inflammation. Inflammatory mediators in the tumor microenvironment activate key transcription factors such as nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3), which subsequently drive the gene expression implicated in cell proliferation, survival, angiogenesis, and immune evasion (Cho et al., 2015, Ong et al., 2020). Tongue cancer, primarily seen as squamous cell carcinoma (SCC), represents about 95 % of oral cancers (Zumsteg et al., 2023). It often develops on the lateral borders of the tongue and is linked to risk factors such as alcohol, human papillomavirus (HPV) infection, and tobacco use (Warnakulasuriya, 2009, Zumsteg et al., 2023).

Generally favourable safety profiles of plant-derived compounds further enhance their potential as adjuncts or alternatives to conventional cancer therapies. In this context, medicinal plants have emerged as a promising source of bioactive compounds (Siridechakorn et al., 2023, Wisuitiprot et al., 2022) capable of modulating inflammatory signalling pathways. Phytochemicals such as epigallocatechin gallate, resveratrol, and curcumin have proved the ability to inhibit NF-κB and STAT3 activation, thereby downregulating cyclooxygenase-2 (COX-2) (Anwar et al., 2023, Gonfa et al., 2023, Kciuk et al., 2023; Wang et al., 2023). These compounds also exhibit antioxidant properties, contributing to the reduction of oxidative stress, another key factor in inflammation-induced carcinogenesis. Notably, honokiol, a natural compound derived from Magnolia species, has demonstrated the ability to suppress STAT3 signalling, thereby inducing apoptosis in oral squamous cell carcinoma (OSCC) cells (Chauhan et al., 2022, Jiang and Li, 2022, Singh et al., 2023, Wang et al., 2023).

Elaeodendron buchananii, a species within the Elaeodendron genus, is well-recognised in traditional medicine systems for its therapeutic potential (https://prota.prota4u.org/protav8.asp?g=pe&p=Elaeodendron%20buchananii). It is an evergreen tree native to eastern Africa, particularly Uganda and Kenya, characterised by a rounded crown and branched morphology. Despite its known toxic properties, the plant has been employed in traditional medicine for diverse therapeutic purposes. Leaf extracts are traditionally used as a vermifuge, oxytocic, tonic, and abortifacient in the management of fever, while chewing the leaves is reported to alleviate diarrhoea. A decoction of the bark has been utilized in the treatment of leukemia, whereas decoctions prepared from the roots are employed in managing infertility, menorrhagia, hemoptysis, and various digestive disorders. Root powder has also been traditionally applied topically for the treatment of syphilis and to promote wound healing (Jennifer et al., 2022, Odak et al., 2018, Omara et al., 2020). Previous reports have highlighted its diverse pharmacological activities, including antioxidant, antimicrobial, anti-inflammatory, and anticancer effects (Nguta et al., 2010). Phytochemical analyses have identified several bioactive compounds in E. buchananii, such as elabunin, lupeol, and buchaninoside, which exhibit significant pharmacological activities, including anti-inflammatory, anticancer, antimicrobial, and antioxidant effects (Kubo and Fukuhara, 1990, Tsanuo et al., 1993, Tsujino et al., 1995).

In light of these properties, the present study was undertaken to evaluate the anti-inflammatory and antiproliferative potential of methanolic extract of E. buchananii against tongue squamous carcinoma cells. The study also employed liquid chromatography–mass spectrometry (LC-MS)–based phytochemical profiling to identify potential bioactive constituents that may underlie the observed biological activities.