Cytotoxic Effects on Cancer Cells Shown by Compounds in Industrial Hemp Roots

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Cannabis compounds other than cannabinoids are being studied for potential uses and benefits. A recently published study examined the effects of neolignans found in hemp roots on cancer cells (1). After the legalization of industrial hemp by the 2018 Farm Bill, the study noted the exploration of low-THC strains of industrial hemp for a variety of uses, such as livestock feed, paper production, building materials, and now possibly the pharmaceutical industry. The study, “Neolignans isolated from industrial hemp (Cannabis sativa L.) roots have cytotoxic effects on cancer cells,” was published in the Journal of Cannabis Research in August 2025. The study was funded by

Using liquid chromatography, peaks in root samples were tentatively identified as neolignans. After the samples were prepared for analysis, their inhibitory concentration 50 (IC50) of the samples were tested against multiple cancer cell lines. The presence of dadahol A was confirmed using a comparison to a commercially available reference standard, and dadahol B was also found in the hemp samples. Purities from dadahols A and B were tested against two high-risk neuroblastoma cell lines, a hepatoblastoma (pediatric liver cancer) cell line, and a Hodgkin’s lymphoma cell line. These four lines were chosen for this study based on their relevance to pediatric cancers.

Highlighted results of the test included:

• The highest cytotoxic activity was seen in semi-pure fractions containing dadahol A and/or dadahol B compared to control in all four lines
• The compounds were shown to have varying effects against cancer cells
• Pure dadahol A showed the lowest inhibitory concentration in all the cell lines

The study stated that this is the first time antiproliferation activity on cancer cells has been demonstrated in the dadahols. Further studies would need to clarify the mechanisms and the molecular basis of the cytotoxicity of these compounds.

“Though industrial hemp is more well-known for its cannabinoid content, it contains hundreds of other phytochemicals that may have uses in the functional food and pharmaceutical industry,” explained the researchers. “Furthermore, utilizing each part of the hemp plant, including the roots, will reduce agricultural waste and provide additional value to growers.”

Other parts of the plant have been recently studied for their potential effects as well. A study published in May 2025 analyzed the phenolics of cannabis leaves using an optimized analytical method and finding flavoalkaloids for the first time (2). This group of secondary metabolites that are present in plants but are less common that flavonoids. “Our analysis again highlights the medicinal potential of Cannabis plant material, currently regarded as waste,” explained study author André de Villiers, in a press release from Stellenbosch University (3). “Cannabis exhibits a rich and unique non-cannabinoid phenolic profile, which could be relevant from a biomedical research perspective.”

Additionally, parts of the hemp plant considered waste have been studied for their nutritional value in livestock feed, for example. Another study published in May 2025 tested the use of spent hemp biomass as a feed for cows, testing the accumulation of cannabinoids in their milk and tissue (4). The researchers found that after a period of withdrawal period, THC was no longer detectable in tissue samples, and the risk of consuming the cannabinoid had been eliminated.

References

1. Brownstein, KJ.; Nieukirk, GE.; Edwards, J.; Thomas, M.; Nguyen, TH.; de Alarcón, PA.; Vermillion, KE.; Gnanamony, M. Neolignans isolated from industrial hemp (Cannabis sativa L.) roots have cytotoxic effects on cancer cells. J Cannabis Res 2025, 7(58). DOI: 10.1186/s42238-025-00316-5
2. McEvoy, E. Phenolic Analysis of Cannabis Reveals Rare Flavoalkaloids in Leaves https://www.cannabissciencetech.com/view/phenolic-analysis-of-cannabis-reveals-rare-flavoalkaloids-in-leaves (accessed 2025-09-02).
3. Fourie-Basson, W. Don’t throw away those Cannabis leaves – they are packed with rare compounds https://www.sun.ac.za/english/Lists/news/DispForm.aspx?ID=11490 (accessed 2025-09-02).
4. McEvoy, E. OSU Study Measures Cannabinoid Levels in Cows Fed Spent Hemp Biomass https://www.cannabissciencetech.com/view/osu-study-measures-cannabinoid-levels-in-cows-fed-spent-hemp-biomass (accessed 2025-09-02).