This study was designed to test the anticancer and anti-inflammation properties of different active ingredient combinations found in different cannabis flower extracts. It was published in the journal Molecules in September 2022.
The authors found in their previous work that the "combination of several terpenes downregulated pro-inflammatory cytokines with efficiency similar or greater than single cannabinoids". In other words, the right combination of terpenes was just as good as a single cannabinoid for reducing inflammatory markers.
The extracts used varied in cannabinoid content, but all were highly THC dominant. THC ranged from 26.5 to 36.9%, CBD from 0.58 to 3.62% and CBGA from 0.64 to 1.71%
They used cancer cell cultures treated with the different extracts. Their anticancer activity was measured using HCC1806 breast squamous cell carcinoma. They found that all the extracts showed anticancer effects, however it varied significantly:
from 66% to 92% of growth inhibition of cancer cells.
Inflammation activity was tested by induction of inflammation with TNF-α/IFN-γ in WI38 human lung fibroblasts. The primary inflammation parameters measured were the expression of COX2 and IL6.
some extracts aggravated inflammation by increasing the expression of COX2/IL6 by 2-fold, other extracts decreased inflammation, reducing expression of cytokines by over 5-fold.
The study also found that THC isolate was significantly less effective (45% vs. 80% inhibition average) than the 25 full-spectrum extracts tested.
The results indicated that terpinene, and likely eucalyptol, were positively correlated with anti-cancer activity.
Terpinene, eucalyptol, p-cymene, β-myrcene and camphor were positively correlated with the anti-inflammatory effect of extracts.
Eucalyptol was the only terpene they found to be positively correlated with BOTH anticancer and anti-inflammatory effects.
The authors' said:
We found that all extracts could inhibit the growth of HCC1806 cells in a dose-dependent manner [high doses worked better]
it appears that THC alone is not responsible for the inhibition of the growth of cancer cells.
most of high-THC extracts demonstrate anti-cancer activity
only certain selected extracts showed anti-inflammatory activity
even 25 extracts are not sufficient to clearly delineate the active ingredient(s) in cannabis or modulating effects of the other minor components.
The full text article is here at PubMed Central.