“Breast cancer is the second leading cause of death among women. Although early diagnosis and development of new treatments have improved their prognosis, many patients present innate or acquired resistance to current therapies. New therapeutic approaches are therefore warranted for the management of this disease.

Extensive preclinical research has demonstrated that cannabinoids, the active ingredients of Cannabis sativa, trigger antitumor responses in different models of cancer.

Most of these studies have been conducted with pure compounds, mainly Δ⁹-tetrahydrocannabinol (THC). The cannabis plant, however, produces hundreds of other compounds with their own therapeutic potential and the capability to induce synergic responses when combined, the so-called “entourage effect”.

Here, we compared the antitumor efficacy of pure THC with that of a botanical drug preparation (BDP).

The BDP was more potent than pure THC in producing antitumor responses in cell culture and animal models of ER+/PR+, HER2+ and triple-negative breast cancer. This increased potency was not due to the presence of the 5 most abundant terpenes in the preparation. While pure THC acted by activating cannabinoid CB₂ receptors and generating reactive oxygen species, the BDP modulated different targets and mechanisms of action. The combination of cannabinoids with estrogen receptor- or HER2-targeted therapies (tamoxifen and lapatinib, respectively) or with cisplatin, produced additive antiproliferative responses in cell cultures. Combinations of these treatments in vivo showed no interactions, either positive or negative.

Together, our results suggest that standardized cannabis drug preparations, rather than pure cannabinoids, could be considered as part of the therapeutic armamentarium to manage breast cancer.”

“It is well documented that cannabinoids, the active ingredients of the hemp plant Cannabis sativa, produce antitumor responses in preclinical models of cancer, by tackling different stages of cancer progression such as uncontrolled cancer cell proliferation and survival, angiogenesis and metastasis. The vast majority of these studies has been performed with pure compounds, mainly Δ⁹-tetrahydrocannabinol (THC). The cannabis plant, however, produces hundreds of additional compounds (other cannabinoids, terpenoids, flavonoids, polyphenols, etc.) that have been much less studied but show promising therapeutic properties (anti-proliferative, anti-inflammatory, immune-stimulant, etc.), and/or the potential capability of enhancing some THC actions, the so-called “entourage effect”.

https://www.sciencedirect.com/science/article/abs/pii/S0006295218302387

“Objectives: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with limited treatment options. Cannabidiol (CBD) has demonstrated anticancer potential, but its clinical application is hindered by poor solubility and nonspecific distribution. This study aimed to develop a folic acid-modified chitosan (FA-CS) nanoparticle system to enhance the targeted delivery and therapeutic efficacy of CBD against TNBC.

Methods: FA-CS@CBD nanoparticles were synthesized and characterized for morphology, size distribution, zeta potential, and stability. Their in vitro anticancer effects were evaluated through cytotoxicity, cellular uptake, apoptosis, and reactive oxygen species (ROS) assays in 4T1 breast cancer cells. The in vivo antitumour efficacy and systemic toxicity were assessed using a TNBC mouse model.

Key findings: FA-CS@CBD nanoparticles exhibited uniform morphology, stable physicochemical properties, and efficient cellular uptake. Compared to free CBD, the nanoparticles significantly enhanced ROS production, induced apoptosis, and inhibited migration in 4T1 cells. In vivo studies demonstrated strong tumour-targeting capability and a tumour inhibition rate of 68.07%, with minimal systemic toxicity.

Conclusions: The FA-CS@CBD nanoparticle system improved the targeted delivery and therapeutic effects of CBD against TNBC while maintaining favorable biocompatibility. These findings highlight the potential of FA-CS-based nanocarriers for enhancing CBD clinical application in breast cancer therapy.”

https://pubmed.ncbi.nlm.nih.gov/40838692/

https://academic.oup.com/jpp/advance-article-abstract/doi/10.1093/jpp/rgaf072/8239116?redirectedFrom=fulltext&login=false

“Introduction: Aromatase inhibitor (AI) therapy reduces breast cancer recurrence risk. However, some patients stop treatment early because of AI-associated musculoskeletal symptoms (AIMSS). AIMSS is due in part to systemic inflammation. Cannabidiol (CBD) has anti-nociceptive and anti-inflammatory properties, making it a potential treatment option for AIMSS.

Methods: Women with stage 0-3 hormone receptor-positive breast cancer experiencing AIMSS enrolled in this phase 2 clinical trial. Patients received CBD (Epidiolex), titrated over 4 weeks to 100 mg BID, for a total of 15 weeks. Patient-reported outcomes were collected serially. The primary endpoint was the number of patients with at least a 2-point reduction in worst pain from baseline to 15 weeks. Statistical analysis was completed using paired t-tests and linear mixed models.

Results: Of 39 eligible patients, 28 completed protocol-directed study treatment. Eleven discontinued treatment due to toxicity (n = 5) or per patient preference (n = 6). Seventeen of 39 patients met the primary endpoint (43.6%, 95% CI [28%, 60%]). Worst pain improved 0.13 per week of treatment (p < 0.001) for all patients; average improvement in worst pain was 1.95 points at the end of 15 weeks. Of the 28 patients who completed the study, average reduction in worst pain was 2.36 points (95% CI [-3.22, -1.49]) between baseline and Week 15.

Conclusion: Treatment with CBD was safe, tolerable, and associated with improvement in joint pain for a subset of patients. Additional studies are needed to further understand the impact of CBD on AIMSS and which patients are most likely to benefit from CBD treatment.”

https://pubmed.ncbi.nlm.nih.gov/40751295/

“Treatment with CBD was associated with an improvement in AIMSS for a subset of patients. Use of CBD was safe and tolerable for women with hormone receptor-positive breast cancer.”

https://onlinelibrary.wiley.com/doi/10.1002/cam4.71117

“Endocrine therapy for estrogen receptor-positive (ER⁺) breast cancer has significantly improved over the last decades. However, it presents some limitations that make the search for novel therapeutic options mandatory.

Several studies have been conducted to understand the anti-tumor potential of cannabinoids in breast cancer. Yet, most of them are focused on the major phytocannabinoids Δ⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD). However, Cannabis has other minor phytocannabinoids whose anti-cancer properties are still to be elucidated.

Here, we investigated the mechanisms of action of four minor cannabinoids, cannabigerol (CBG), cannabidivarin (CBDV), cannabinol (CBN), and cannabichromene (CBC), in 2D and 3D ER⁺ breast cancer models.

These cannabinoids dysregulate MCF-7aro cell cycle progression, induce apoptosis by different mechanisms, and inhibit the growth of MCF-7aro spheroids. CBG exerts its effects through a down-regulation of both ER and AR protein levels, while CBDV reduces aromatase protein levels. CBN and CBC simultaneously affect the three targets, ER, aromatase, and AR.

In fact, CBN and CBC present an AR-dependent cell death, down-regulate aromatase levels, and act as ER negative regulators impairing cancer cell growth. CBN caused the most pronounced effects.

Overall, this study highlights the anti-cancer properties and the therapeutic potential of these minor cannabinoids in ER⁺ breast cancer.”

https://pubmed.ncbi.nlm.nih.gov/40615070/

https://www.sciencedirect.com/science/article/pii/S1388198125000666?via%3Dihub

“Cannabidiol (CBD) has shown promise in treating cancers with an inflammatory microenvironment.

Although it has been demonstrated that IL-1β induces epithelial-mesenchymal transition (EMT) of MCF-7 cells and CBD reverts this process, in restoring the epithelial non-invasive phenotype, there is limited understanding of how this cannabinoid regulates these processes.

In this work, MCF-7 cells were induced to adopt an aggressive phenotype (6D cells), which was reversed by CBD.

Then, protein expression was analyzed by mass spectrometry to compare 6D vs. MCF-7 cells and 6D+CBD vs. 6D cells proteomes. Novel proteins associated with EMT and CBD signaling were identified. Twenty-four of them were oppositely regulated by IL-1β and CBD, suggesting new points of crosstalk between the IL-1β and CBD signaling pathways.

From the data, two protein networks were constructed: one related to EMT with 58 up-regulated proteins and another with 21 related to CBD signaling. The first one showed the proteins BRCA1, MSN, and CORO1A as the key axis that contributes to the establishment of a mesenchymal phenotype. In the CBD signaling, the key axis was formed by SUPT16H, SETD2, and H2BC12, which suggests epigenetic regulation by CBD in the restoration of an epithelial phenotype of breast cancer cells, providing new targets for anticancer therapy.”

https://pubmed.ncbi.nlm.nih.gov/40429863/

“All these results provide new important insights that could help to understand how CBD counteracts the effects of IL-1β and the restoration of the epithelial phenotype as a possible control of cancer progression.”

https://www.mdpi.com/1422-0067/26/10/4721

“Triple-negative breast cancer (TNBC) is an invasive and difficult-to-treat carcinoma that represents 15-20 % of breast malignancies and is frequently diagnosed in younger women. Chemotherapy is the mainstay treatment approach.

Cannabidiol (CBD), the main non-psychoactive cannabinoid, has shown a potential anticancer activity in TNBC, enhancing the effect of conventional antineoplastics.

This research aims to develop in situ forming implants (ISFIs) as a long-acting depot formulation of CBD with potential application in TNBC. This formulation is intended to be administered in the tumor site during neoadjuvant chemotherapeutic regimens, allowing a controlled CBD release. ISFIs were elaborated with 100 mg of polycaprolactone (PCL) and 2.5 mg (2.5-CB-ISFI), 5 mg (5-CB-ISFI) or 10 mg (10-CB-ISFI) of CBD dissolved in 400 µL of NMP. All the formulations exhibited a controlled drug release for around two months. 10-CB-ISFI formulation with the highest CBD content and the most suitable CBD release profile was selected for biological studies.

This formulation inhibited the proliferation and migration of MDA-MB-231 and 4T1 cells and exerted an antiangiogenic effect in ovo. Interestingly, the antiangiogenic activity of 10-CB-ISFI was higher compared with CBD in solution administered at the same concentration, showing vascular inhibition percentages of around 80 % and 60 %, respectively.

Finally, this formulation reduced the growth of MDA-MB-231-derived tumors developed in the chorioallantoic membrane (CAM) model. The single administration of 10-CB-ISFI exhibited a similar antitumor efficacy to the daily administration of CBD in solution (≈60 % tumor growth inhibition).

Therefore, the injectable depot formulation of CBD developed in this work showed a promising utility in TNBC treatment.”

https://pubmed.ncbi.nlm.nih.gov/40349999/

https://www.sciencedirect.com/science/article/pii/S0378517325005472?via%3Dihub