Pancreatic cancer is one of the deadliest malignancies worldwide, with a 9 % estimated 5-year relative survival rate (Lambert et al., 2021). Estimates from GLOBOCAN 2020 show that pancreatic cancer is the 7th top cause of cancer mortality and the 12th most prevalent malignancy (Ilic and Ilic, 2022). Unfortunately, by 2030, it is anticipated to rank as the second most common cause for cancer-related deaths. The main reasons for such high mortality are late diagnosis, which typically occurs at an advanced tumor stage, inadequate treatment, high rate of recurrence and early metastasis (Olajubutu et al., 2023). Even though surgical resection of the tumor is the ultimate treatment, a very small number of patients (around 9–15 %) are eligible for surgery due to the late diagnosis (El-Zahaby et al., 2019). The three primary conventional treatment modalities currently in use in clinical settings are chemotherapy, radiation therapy and immunotherapy (Hani et al., 2021). Chemotherapy has long been the first-line treatment for the majority of cases. However, the pharmaceutical functionality of chemotherapeutics is greatly impeded by their unselective cytotoxicity, poor bioavailability and low intratumoral targeting, permeation and localization, resulting in therapeutic failure (Olajubutu et al., 2023). Consequently, there is an urgent need for more effective cancer therapeutic options.

In this regard, phytotherapeutics have recently attracted a lot of attention as potential anticancer agents. Phytotherapeutics offer a safe, affordable, and highly effective alternative to conventional chemotherapeutics. As an example, flavonoids have an established anticancer potentiality as one of the most common polyphenols (Salehi et al., 2018). Among them, genistein (Gen) is a flavonoid with exceptional pharmacological activities, including antibacterial, antiviral, antioxidant, anti-inflammatory and anticancer effects (Sharifi-Rad et al., 2021). Specifically, the cytotoxic efficacy of Gen has been previously established on pancreatic cancer (Bi et al., 2018). Bi et al. (Bi et al., 2018) confirmed that Gen had a dose-dependent antiproliferative activity on two distinct pancreatic cancer cell lines (MIA-PaCa-2 and PANC-1), with IC50 values of 20 and 25 µM, respectively. The higher IC50 (120 µM) on non-cancerous pancreatic ductal epithelial cell line (H6C7) provided further evidence of Gen safety. According to reports (Bi et al., 2018, Javed et al., 2022), Gen inhibits the growth of tumors by inhibiting the cell cycle, inducing ROS-mediated mitochondrial apoptosis, and controlling STAT3. Another class of phytotherapeutics, essential oils are currently gaining great attention for their unique pharmacological aptitudes, including antibacterial, antifungal, anti-inflammatory, antioxidant and anticancer potential (Mutlu-Ingok et al., 2020). Of special interest is frankincense oil (FO), an essential oil of the milky gum resin that comes from Boswellia trees (family Burseraceae) and has been demonstrated to exert anti-inflammatory and anti-tumor actions (Ni et al., 2012, Park et al., 2011, Khajehdehi et al., 2022). According to Xiao Ni et al. (Ni et al., 2012), FO stimulates anti-proliferative and pro-apoptotic actions in human pancreatic cancer cell lines and delays cancer progression in a mouse cancer model. Even though phytotherapeutics are pharmacologically promising, their clinical application has been restricted due to the low solubility, low bioavailability and low stability (Shi et al., 2012, Aly et al., 2023). In this context, nanodrug delivery can be efficiently leveraged for effective therapeutic anticancer outcomes.

Harnessing nanodrug delivery systems can offer controlled release of the loaded therapeutics (Hani et al., 2021). Moreover, as anticancer therapeutic platforms, nanodrug delivery systems can contribute passive targeting and high tumor drug delivery via the enhanced permeation and retention (EPR) effect by virtue of their nanosize (Nakamura et al., 2016). Among the promising nanocarriers, lyotropic liquid crystals have garnered attention for their potential to deliver both hydrophobic and hydrophilic drugs and their application-versatility (Abourehab et al., 2022, Varghese et al., 2022). Cubosomes (Cub) are one type of liquid crystals, which are bicontinuous lipid cubic-phase nanoparticle dispersions, featuring two interconnected water channels separating their lipid bilayers in a way that creates an uninterrupted, regular cubic symmetrical structure (Abourehab et al., 2022). As a result, they demonstrate great stability and a higher surface area than lamellar liposomes, allowing the effective entrapment and sustained release of drugs (Abourehab et al., 2022). Indeed, Cub have been effectively employed as anticancer delivery platforms (Varghese et al., 2022). For example, loading docetaxel within Cub has increased its in vitro cytotoxicity on mouse colorectal (C-26) cell line as well as its in vivo anticancer effect in mice, compared to docetaxel solution (Dawoud et al., 2020). Therefore, adopting Cub for the codelivery of Gen and FO would have a great anticancer prospect.

Surface decoration of nanocarriers with specific active tumor-targeting ligands have long been adopted to ensure the site-specific delivery and intratumoral localization of the loaded cargo, with low off-target toxicity (Priya et al., 2023). Hyaluronic acid (HA) is one of the commonly used CD44 receptor-targeting ligands as a biocompatible, non-immunogenic and biodegradable mucopolysaccharide. Through receptor-mediated endocytosis, HA can be used to selectively interact with tumors overexpressing CD44 receptors, like pancreatic cancer (Nisha et al., 2022, Bajracharya et al., 2022). For example, Pramanik et al. demonstrated that HA-tagged cubosomes dramatically increased the cytotoxicity of acetyl acetonate compared to untargeted cubosomes in the CD44-positive cell lines; MDA-MB-231 (breast cancer) and HT29 (colon cancer) (Pramanik et al., 2022).

Within this framework, in this study, we aimed to develop HA-coated Gen-loaded Cub that are further integrated with the bioactive FO (HA/Gen-FO-Cub) for both passive and active targeting and effective management of pancreatic cancer. The novel Gen-FO-Cub was first developed via the hydrotrope method then coated with HA as targeting ligand. The developed nanocarrier was thoroughly characterized for various in vitro pharmaceutical aspects. In vitro anticancer efficacy was studied on PANC-1 cells, elaborating cytotoxicity, cellular uptake and antimigratory activity. Furthermore, in vitro cytocompatibility was investigated on normal human dermal fibroblasts (HDF). Finally, the in vivo anticancer activity was verified in an orthotopic xenograft pancreatic cancer mouse model via the assessment of tumor progression, tumor biomarker analysis, histological, histomorphometric, and immunohistochemical analyses.