Meta-analysis of medical cannabis outcomes and associations with cancer

“Background: Growing bodies of evidence suggest that cannabis may play a significant role in both oncological palliative care and as a direct anticarcinogenic agent, but classification as a Schedule I substance has complicated research into its therapeutic potential, leaving the state of research scattered and heterogeneous. This meta-analysis was conducted to determine the scientific consensus on medical cannabis’ viability in cancer treatment.

Objective: The aim of this meta-analysis was to systematically assess the existing literature on medical cannabis, focusing on its therapeutic potential, safety profiles, and role in cancer treatment.

Methods: This study synthesized data from over 10,000 peer-reviewed research papers, encompassing 39,767 data points related to cannabis and various health outcomes. Using sentiment analysis, the study identified correlations between cannabis use and supported, not supported, and unclear sentiments across multiple categories, including cancer dynamics, health metrics, and cancer treatments. A sensitivity analysis was conducted to validate the reliability of the findings.

Results: The meta-analysis revealed a significant consensus supporting the use of medical cannabis in the categories of health metrics, cancer treatments, and cancer dynamics. The aggregated correlation strength of cannabis across all cancer topics indicates that support for medical cannabis is 31.38× stronger than opposition to it. The analysis highlighted the anti-inflammatory potential of cannabis, its use in managing cancer-related symptoms such as pain, nausea, and appetite loss, and explored the consensus on its use as an anticarcinogenic agent.

Discussion: The findings indicate a strong and growing consensus within the scientific community regarding the therapeutic benefits of cannabis, particularly in the context of cancer. The consistent correlation strengths for cannabis as both a palliative adjunct and a potential anticarcinogenic agent redefine the consensus around cannabis as a medical intervention.

Conclusion: The consistency of positive sentiments across a wide range of studies suggests that cannabis should be re-evaluated within the medical community as a treatment option. The findings have implications for public health research, clinical practice, and discussions surrounding the legal status of medical cannabis. These results suggest a need for further research to explore the full therapeutic potential of cannabis and address knowledge gaps.”

“The data presented here indicate that cannabis has a well-established role in managing symptoms related to cancer and may have both direct and indirect anticancer properties, which challenges the notion that it has no accepted medical use.”

https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2025.1490621/full

Effect of cannabinoids on the efficacy and side effects of anticancer therapeutic strategies – Current status of preclinical and clinical research

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“Cannabinoids have attracted increasing attention in cancer research in recent decades. A major focus of current preclinical and clinical studies is on the interactions and potential risks when combined with chemotherapeutic agents, targeted therapies and other anticancer strategies.

Given the extensive preclinical data on additive, synergistic and, in some cases, antagonistic tumor cell killing effects of chemotherapeutic agents and cannabinoids when co-administered, a critical analysis of these data seems essential. The available data mainly relate to combination treatments for glioblastoma, hematological malignancies and breast cancer, but also for other cancer types.

Such an analysis also appears necessary because cannabinoids are used as an option to treat nausea and vomiting caused by chemotherapy, as well as tumor-related pain, and cancer patients sometimes take cannabinoids without a medical prescription. In addition, numerous recent preclinical studies also suggest cannabinoid-mediated relief of other chemotherapy-related side effects such as peripheral neuropathy, nephrotoxicity, cardiotoxicity, cystitis, bladder complications and mucositis.

To summarize, the data available to date raise the prospect that cannabinoids may increase the efficacy of chemotherapeutic agents while reducing their side effects. However, studies on interactions are mostly limited to cytotoxicity analyses. An equally thorough investigation of the effects of such combinations on the immune system and on the tumorigenic levels of angiogenesis, invasion and metastasis is still pending. On this basis, a comprehensive understanding for the evaluation of a targeted additional treatment of various cancers with cannabinoids could be established.”

https://pubmed.ncbi.nlm.nih.gov/40221102/

“The anticancer effect of various phytocannabinoids, including Δ9-tetrahydrocannabinol (THC), was first demonstrated in animal experiments in 1975 (Munson, Harris, Friedman, Dewey, & Carchman, 1975). After the discovery of the endocannabinoid system in the early 1990s, these effects were confirmed in numerous preclinical studies in a variety of different neoplastic entities. Based on these findings and studies demonstrating the anticancer effects of cannabinoids on various hallmarks of tumorigenesis, cannabinoids have increasingly become the focus of scientific discussions as systemic tumor therapies in recent years (for an overview, see Ramer & Hinz, 2015; Hinz & Ramer, 2019). From a preclinical point of view, the systemic antitumor effects of cannabinoids thus represent the basis for combining cannabinoids with chemotherapies, which can increase the effectiveness of chemotherapeutic agents and overcome resistance.”

https://www.sciencedirect.com/science/article/abs/pii/S0163725825000634?via%3Dihub

Effects of cannabinoids on immune checkpoint inhibitor response: CCTG pooled analysis of individual patient data

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“Background: Immune checkpoint inhibitors (ICIs) benefit patients across various tumor types. ICIs block cancer and T-cell interactions whereas cannabinoids may inhibit T-cell activation, reducing lysis of tumor cells. Interactions between cannabinoid use and dual ICI treatment remain unknown.

Methods: Individual patient data from 4 Canadian Cancer Trials Group (CCTG) trials of patients treated with dual ICI ± chemotherapy (n = 684) were pooled. Cochran – Mantel – Haenszel and log-rank tests (stratified by trial/treatment arms) correlated cannabinoid use with clinicopathologic characteristics, Best Overall Response (BOR)/iBOR per RECIST 1.1/iRECIST, Progression-Free Survival (PFS)/iPFS, Overall Survival (OS) and immune-related adverse events (irAEs).

Results: Sixty-five (9.5%) patients took cannabinoids at any time on trial, 32 (4.7%) of which were using cannabinoids at baseline. By multivariate analysis, cannabinoid use at baseline was significantly associated with improved iPFS (0.05), but not iBOR (p = 0.15), PFS (p = 0.12), OS (p = 0.35) or incidence of grade 1/2 or 3/4 irAEs (p = 0.96 and 0.65 respectively). Results were not significantly different with cannabinoid use at any time on trial.

Conclusion: Improved iPFS with cannabinoid use in patients treated with durvalumab plus tremelimumab ± chemotherapy did not translate into OS benefits. This study supports the safe use of cannabinoids in the context of combination ICI therapy.”

https://pubmed.ncbi.nlm.nih.gov/40184324/

“Plain Language Summary

Immune checkpoint inhibitors (ICI) have become an important treatment option for cancer patients and has been associated with improved survival outcomes across various tumor types. Cannabinoids are active components of cannabis and include tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis use has increased in Canadian cancer patients and is often used for symptom management. Some studies have suggested that cannabinoids can alter the function of the immune system, which could impact the effectiveness of immune checkpoint inhibitors. Therefore, we aimed to evaluate whether cannabinoid use might impact the effectiveness of combination ICI treatment with durvalumab plus tremelimumab (with/without chemotherapy) using data from four clinical trials completed through the Canadian Cancer Trials Group (CCTG). We found no significant difference in response, survival outcomes or adverse events in patients who used cannabinoids with combination ICI treatment compared to cannabinoid non-users. This study supports the safe use of cannabinoids in the context of combination ICI therapy.”

https://www.tandfonline.com/doi/full/10.1080/1750743X.2025.2485012

Cannabidiol from Conventional to Advanced Nanomedicines for the Management of Cancer-Associated Pain

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“Chemotherapy-induced pain is one of the major challenges that hamper the patient’s quality of life. Several cases of insufficient pain management were reported globally, especially in the case of patients who do not respond well to conventional pain management regimes and opioid analgesics. Additionally, conventional pain management has several shortcomings, and evidence suggests that cannabidiol has the potential to overcome those shortcomings.

Cannabidiol (CBD) is a non-psychoactive compound of the Cannabis plant that shows an effective outcome in chemotherapy- induced pain as well as in cancer treatment, as it possesses anti-inflammatory and analgesic properties.

The mechanism of pain and its management by cannabidiol, with all possible evidence, is well summarised in the paper. This article concludes the types of pain experienced by cancer patients, the effectiveness of CBD in the management of pain, and challenges faced by patients after using Cannabidiol with various case studies.

Later, antitumor efficacy studies of CBD were disclosed, and its various types of formulations and nano-formulations were summarized in the paper. Overall, the paper establishes the role of cannabidiol in Chemotherapy-induced pain.”

https://pubmed.ncbi.nlm.nih.gov/40151084/

https://www.eurekaselect.com/article/147414

Parthanatos and apoptosis: unraveling their roles in cancer cell death and therapy resistance

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“Cell death is a fundamental process that needs to be maintained to balance cellular functions and prevent disease. There are several cell death pathways; however, apoptosis and parthanatos are the most prominent and have important roles in cancer biology. As an extremely well-regulated process, apoptosis removes damaged or abnormal cells via caspase activation and mitochondrial involvement.

Unlike in the healthy cells, the loss of ability to induce apoptosis in cancer permits tumor cells to survive and multiply out of control and contribute to tumor progression and therapy resistance. On the contrary, parthanatos is a caspase-independent metabolic collapse driven by poly (ADP-ribose) polymerase 1 (PARP1) overactivation, translocation of apoptosis-inducing factor (AIF), and complete DNA damage. Several cancer models are involved with parthanatos. Deoxypodophyllotoxin (DPT) induces parthanatos in glioma cells by excessive ROS generation, PARP1 upregulation, and AIF nuclear translocation.

Like in acute myeloid leukemia (AML), the cannabinoid derivative WIN-55 triggers parthanatos, and the effects can be reversed by PARP inhibitors such as olaparib.

Developing cancer treatment strategies involving advanced cancer treatment strategies relies on the interplay between apoptosis and parthanatos. However, such apoptosis-based cancer therapies tend to develop resistance, so there is an urgent need to look into alternative pathways like parthanatos, which may not always trigger apoptosis.

In overcoming apoptosis resistance, there is evidence that combining apoptosis-inducing agents, such as BH3 mimetics, with PARP inhibitors synergistically enhances cell death.

Oxidative stress modulators have been found to promote the execution of parthanatic and apoptotic pathways and allow treatment. In this review, apoptosis and parthanatos are thoroughly compared at the molecular level, and their roles in cancer pathogenesis as related to cancer therapeutic potential are discussed.

We incorporate recent findings to demonstrate that not only can parthanatos be used to manage therapy resistance and enhance cancer treatment via the combination of parthanatos and apoptosis but also that immunity and bone deposition can feasibly be employed against long-circulating cancer stem cells to treat diverse forms of metastatic cancers.”

https://pubmed.ncbi.nlm.nih.gov/40166425/

“Cannabinoids induce cell death in leukaemic cells through Parthanatos and PARP-related metabolic disruptions.”

https://pubmed.ncbi.nlm.nih.gov/38461169/

Early oral administration of THC:CBD formulations prevent pain-related behaviors without exacerbating paclitaxel-induced changes in weight, locomotion, and anxiety in a rat model of chemotherapy-induced neuropathy

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“Rationale: Paclitaxel-induced neuropathy stands out as the primary, dose-limiting side effect of this extensively used chemotherapy agent. Prolonged hypersensitivity and pain represent the most severe clinical manifestations. Effective preventive and therapeutic strategies are currently lacking.

Objectives: Our study aimed to assess the impact of early oral administration of pharmaceutical-grade formulations containing the phytocannabinoids THC and CBD in a rat model of paclitaxel-induced neuropathy.

Methods: The experimental design involved the co-administration of paclitaxel and cannabinoid formulations with different THC to CBD ratios (THC:CBD 1:1 and THC:CBD 1:20) to adult male rats. Mechanical and thermal sensitivity, locomotor activity, vertical exploratory behaviors, anxiety-related parameters, weight gain, food and water consumption, and liver functionality were assessed.

Results: Daily administration of THC:CBD 1:1 successfully prevented paclitaxel-induced cold allodynia, while THC:CBD 1:20 effectively prevented both thermal and mechanical hypersensitivities. Additionally, THC:CBD 1:1 formulation restored rearing behavior, significantly reduced by paclitaxel. Conversely, neither cannabinoid formulation was able to counteract paclitaxel-induced hypo-locomotion, reduced vertical exploratory activity, increased anxiety-like behaviors, attenuated weight gain, or decreased food and water intakes. However, the formulations employed did not induce further alterations or toxicity in animals receiving paclitaxel, and no signs of liver damage were detected.

Conclusions: Our results suggest a differential therapeutic effect of two THC:CBD formulations on pain-related behaviors and spontaneous activities, particularly in the context of peripheral neuropathy. These formulations represent a promising therapeutic strategy not only to managing pain but also for enhancing daily activities and improving the quality of life for cancer patients.”

https://pubmed.ncbi.nlm.nih.gov/40163146/

Extraction of Cannabinoids and Terpenes from Hemp Flowers and Leaves (Cannabis sativa L., Futura 75): Chemical Profiling and Evaluation of Anticancer Properties

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“This study investigated efficient extraction methods for cannabinoids and terpenes from the above-ground parts of Futura 75, focusing on two techniques: pressurized extraction and magnetic stirrer-assisted extraction. The effects of solvent type, temperature, time, and pressure were evaluated using five organic solvents and two binary solvent systems.

Cannabinoid profiles of obtained extracts were analyzed using gas chromatography coupled with mass spectrometry (GC-MS), while terpene profiles were characterized through solid-phase microextraction (SPME) combined with GC-MS. Next, two selected extracts with the highest content of cannabinoid and terpene fractions (Futu1 and Futu2) were tested for antiproliferative activity toward cancer cell lines (MV4-11, AGS, HT-29, MDA-MB-468, MCF-7) and their cytotoxicity was evaluated on non-tumorigenic MCF-10A cells. Extract Futu1 contained 51.57% cannabinoids, 9.8% monoterpenes, and 90.2% sesquiterpenes in the terpene fraction. Futu2 exhibited a higher proportion of monoterpenes in the terpene fraction (19.6% monoterpenes and 80.4% sesquiterpenes) and consisted of 49.49% cannabinoids.

Both extracts exhibited higher selectivity for cancer cells over non-tumorigenic cells, with Futu2 demonstrating stronger antiproliferative properties.”

https://pubmed.ncbi.nlm.nih.gov/40142100/

“Cannabis sativa L., commonly known as hemp, belongs to the Cannabaceae family, which includes two primary cannabis varieties: hemp (Cannabis sativa L. var. sativa) and marijuana (Cannabis sativa L. var. indica).”

“The effects of two selected extracts from the Futura 75 hemp variety—containing cannabinoids and terpene fractions with differing monoterpene-to-sesquiterpene ratios—were investigated for their potential to inhibit cancer cell growth and their safety concerning healthy breast cells. The results indicate that while the extracts are less active than the tested individual cannabinoids, they exhibit significantly higher selectivity toward cancer cells compared to non-tumorigenic cells. Furthermore, the extract with a higher monoterpene content (Futu 2) demonstrated slightly stronger antiproliferative activity.”

https://www.mdpi.com/1420-3049/30/6/1325

A Multicenter Feasibility Study of a Novel Curriculum for Oncology Trainees Regarding Medical Cannabis

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“Background: Oncology providers often lack the confidence to make clinical recommendations about medical cannabis (MC). This study aimed to develop and evaluate the feasibility of implementing an educational curriculum on the use of MC in patient care for oncology trainees.

Methods: A multidisciplinary team designed an educational curriculum for MC use in oncology. The curriculum was piloted as a 1-hour interactive webinar across 8 United States-based hematology/oncology fellowship programs between 2022 and 2023. Incentivized surveys measuring feasibility outcomes, including cultural attitudes/norms, acceptability, compatibility, and self-efficacy (a composite index of self-confidence in discussing MC efficacy, risks, modes of use, and role in symptom management), were distributed before, immediately after, and 12 weeks post-webinar.

Results: Of 103 trainees, 75 (72.8%) completed the pretraining survey and 66 (64.1%) completed the posttraining survey. Most respondents believed discussions about the role of MC in symptom management were valuable (n=56; 74.7%), though few (14.7%) believed trainees were expected to engage in such discussions. Most participants rated the curriculum as helpful (92.4%), beneficial for oncology trainees (84.8%), and likely to be recommended to colleagues (87.9%). Post-webinar, 78.8% of participants reported an increased likelihood of initiating discussions with patients regarding MC. There were significant improvements in the composite self-confidence index from pre- to post-webinar (2.7% vs 65.2%; P<.001), which persisted in the follow-up surveys (n=36; response rate, 34.9%).

Conclusions: This multisite study demonstrates the feasibility of implementing a novel curriculum focused on MC for oncology trainees. These findings can guide the design of a prospective, multi-institutional study to evaluate knowledge expansion, retention, and behavioral changes resulting from the intervention.”

https://pubmed.ncbi.nlm.nih.gov/40073833/

“Our prior work demonstrated that training in MC use for patients with cancer is an area of unmet need among hematology/oncology trainees. The current study demonstrated the feasibility and acceptability of developing and delivering a virtual webinar curriculum on MC for hematology/oncology fellows. Most trainees enjoyed the format and found the content useful and applicable to their practice and education. We observed sustained improvements in self-reported confidence in conducting clinical discussions across all domains included in the curriculum. Furthermore, participants reported increased discussions about MC with patients following the training, aligning with recent expert consensus guidelines. Future efforts should focus on refining this curriculum based on emerging data in the field, developing similar interventions for other oncology health care professionals, and exploring strategies to sustain these educational initiatives. Such efforts are essential to ensure broad implementation, maximize knowledge retention, and facilitate meaningful behavioral changes in real-world clinical practice.”

https://jnccn.org/view/journals/jnccn/23/3/article-p82.xml

A Green Microwave-Assisted Extraction of Cannabis sativa L. Extract and Its Cytotoxic Activity Against Cancer Cells

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“Objectives: This study aimed to explore the use of D-limonene and some vegetable oils with different amounts of saturated and unsaturated fatty acids as alternative green solvents for microwave-assisted extraction (MAE) of cannabis (Cannabis sativa L.). A standardized cannabis extract was selected to evaluate its potential as a chemopreventive agent.

Materials and methods: Alternative green solvents, powder-to-solvent ratios, and irradiation cycles were determined to optimize the MAE conditions. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to assess the cytotoxic effects against human breast cancer (MCF-7), liver cancer (HepG2), and mammary epithelium (hTert-HME1) cell lines.

Results: The extracts obtained from D-limonene and palm oil contained the highest concentrations of cannabidiol (CBD) and D-tetrahydrocannabinol (THC). A standardized D-limonene extract of cannabis (DEC) containing 0.03% w/w CBD and 1.37% w/w THC was selected for the evaluation of cytotoxic activity compared with CBD and THC. The results revealed that CBD and THC exhibited significant cytotoxic effects (p<0.05) against MCF-7 and HepG2, with the 50% inhibitory concentration (IC50) values of 18.5 and 12.37 μg/mL for CBD and 24.21 and 4.30 μg/mL for THC, respectively, whereas DEC exhibited moderate cytotoxicity against MCF-7 (IC50 of 488.85 μg/mL). However, CBD and THC exhibited significant cytotoxicity (p<0.05) against hTert-HME1 (IC50 values of 35.61 and 25.63 μg/mL, respectively), whereas DEC exhibited low cytotoxicity against hTert-HME1 (IC50 of 1.537.03 μg/mL).

Conclusion: DECs containing appropriate levels of THC and CBD have the potential to be candidates for cancer treatment. However, further investigations are required to improve the efficacy and safety profiles.”

https://pubmed.ncbi.nlm.nih.gov/40052396/

“The present study identified D-limonene and palm oil as promising alternative green solvents for extracting cannabinoids from cannabis inflorescences under MAE optimal conditions. The MAE method offers several advantages, including reduced time and energy consumption. In this study, DEC exhibited moderate cytotoxicity against MCF-7 cells with higher selectivity than CBD and THC. Therefore, DEC containing an appropriate amount of THC and CBD may exhibit a more satisfying anticancer effect and be a promising candidate for cancer treatment. However, additional research is required to understand the mechanisms of anticancer activity and to investigate additional efficacy and safety profiles.”

https://www.turkjps.org/articles/a-green-microwave-assisted-extraction-of-c-lessemgreatersativalessemgreater-l-extract-and-its-cytotoxic-activity-against-cancer-cells/doi/tjps.galenos.2025.33490

Association of Financial Wellness with Patterns of Medical Cannabis Use and Patient-Reported Outcomes in Adults with Cancer

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“Objective: Despite increasing use of medical cannabis to manage cancer-related symptoms, U.S. payers do not reimburse medical cannabis, leaving patients responsible for all associated costs. We assessed how self-reported financial well-being is associated with patterns of cannabis consumption, out-of-pocket costs, and impact on symptoms in patients with cancer.

Method: From December 2021 to January 2022, we surveyed patients with cancer enrolled in the Minnesota Medical Cannabis Program. The mailed survey included cancer history, cannabis use history, symptom changes and sociodemographic questions including income and perceived financial wellness. We conducted descriptive analyses.

Results: Of 797 eligible adults, 220 (28%) responded to the survey. Two hundred eleven answered a question about current household income as living comfortably (LC, 45%; n = 95) or not living comfortably (NLC, 55%; n = 116). The NLC group reported lower incomes (47% vs 8% with annual incomes <$50,000) and were typically younger, unmarried, unemployed, or disabled. NLC group purchased more vaporizers (48% vs 27%), used products high in THC (92% vs 82%), and reported higher cannabis costs (40% vs 21% spending $200+/month). The NLC group more often stopped or used cannabis less frequently than they would like (54% versus 32%), frequently citing costs as a reason (85% vs 39%). Both NLC and LC groups typically used cannabis daily and reported a high degree of symptom improvement.

Conclusions: Patients with cancer using cannabis report significant improvements in cancer-related symptoms. High out-of-pocket costs for cannabis may be especially burdensome among those already financially struggling, raising questions about affordability of and equitable access to this therapy.”

https://pubmed.ncbi.nlm.nih.gov/39968481/

https://publications.sciences.ucf.edu/cannabis/index.php/Cannabis/article/view/243