CBD Has ‘Substantial Promise’ To Combat Tumors From Cancer, Scientific Review Shows

Cannabidiol (CBD), a non-intoxicating compound in marijuana, “holds substantial promise as an anti-tumor agent” in addition to its other anti-inflammatory properties, a new scientific review

Scientists explored CBD’s effect on many types of cancer—including some of the most aggressive ones, such as glioblastoma, which affects the brain. They also noted it can help suppressing the growth and metastasis of other cancers, including breast, lung, colorectal, ovarian and prostate, among others.

“CBD exhibits multi-targeted anti-tumor effects by disrupting key cancer hallmarks,” they found.

The paper, funded by National Natural Science Fund of China, was designed as a systematic review of previous studies evaluating the cancer fighting qualities of CBD.

The idea behind much of the research is to study how cancer cells survive by hijacking normal biological signals like growth cues, stress responses and immune pathways. The novelty scientists found was that CBD doesn’t seem to target just one of these systems and instead nudges several of them at once, pushing cancer cells toward collapse through overlapping and complementary effects.

In colon cancer models, for example, CBD interferes with a receptor called GPR55, which helps tumors grow and migrate. Blocking that receptor weakens a pathway cancer cells rely on to divide quickly, and in some cases makes tumors more responsive to chemotherapy. Other experiments show CBD dialing down genes linked to aggressive growth while switching on stress-related pathways that slow things down.

Lung and breast cancers appear to respond in related but slightly different ways. In non-small cell lung cancer, combinations of CBD and THC reduce tumor growth by interfering with epithelial-mesenchymal transition, the process that allows cancer cells to spread. In breast cancer models, CBD has been shown to stop cells mid-cycle, trigger programmed cell death and activate autophagy, the cell’s internal recycling system turned destructive.

“Cannabidiol (CBD), an FDA-approved and well-tolerated compound, demonstrates promising antitumor effects by inhibiting cancer growth, metastasis, and angiogenesis, while also alleviating cancer-related symptoms such as pain and nausea.”

There are also practical challenges, however. CBD is poorly absorbed when taken by mouth and is heavily metabolized, which means only a fraction may reach tumor tissue. To get around this, scientists are exploring nanoparticle-based delivery systems designed to improve absorption, target tumors more precisely and minimize side effects.

Looking ahead, researchers say progress will depend on careful, methodical work. Tools like single-cell sequencing could help clarify how different tumor populations respond to CBD. Well-designed clinical trials will be essential to determine whether the effects seen in the lab translate into benefits for patients, especially when CBD is used alongside standard treatments.

The study’s authors, who are affiliated with medical schools throughout China, noted the need to further explore the promise of CBD’s anti-tumor properties.

“Future trials must stratify patients by tumor type and molecular markers to establish correlations between dosing, timing, and efficacy,” they wrote. The paper, which was not peer reviewed, was published in the December 2025 issue of the scientific journal Phytomedicine.

The new study follows a series of encouraging discoveries related to CBD’s properties.

In 2025, for example, a paper published in the journal Pharmacology & Therapeutics, assessed a range of clinical and preclinical findings that the efficacy of chemotherapy drugs can be enhanced by medical marijuana.

In a sign of greater acceptance of medical applications of cannabis, President Donald Trump’s choice to serve as the next White House drug czar has called medical marijuana a “fantastic” treatment option for seriously ill patients and said she doesn’t object to legalization, even if she might not personally agree with the policy.

Also last year, a study found that “patients with cancer using cannabis report significant improvements in cancer-related symptoms.”

Marijuana Users Are Being Unjustly Jailed For Allegedly Driving Under The Influence, Government-Funded Study Shows

Laws aimed at preventing marijuana-impaired driving in almost 20 states are causing innocent people who show no signs of impairment to be criminalized and imprisoned for allegedly operating vehicles while under the influence, a new government-funded study shows.

Lawmakers and regulators aiming to reduce drug-impaired driving have long sought to apply a familiar strategy from alcohol enforcement: setting a numerical limit of THC in the bloodstream beyond which a driver is presumed to be impaired, commonly referred to as a “per se” amount.

But the new study suggests that approach may be badly misaligned with the science related to impairment from cannabis, the components and metabolites of which can remain in the body day or weeks after use—when impairment is no longer an issue.

“Many regular users of cannabis exceed zero tolerance and per se THC cutpoint concentrations days after their last use, risking legal consequences despite no evidence of impairment,” the study, which was published in the scientific journal Clinical Chemistry and partially funded by the National Institutes of Health and the State of California, found.

The findings echo earlier research showing weak or inconsistent links between THC blood levels and crash risk. Large epidemiological studies have found that while marijuana use may slightly increase collision risk, the effect is far smaller than that of alcohol use.

“One of the primary problems with using THC concentrations in per se legislation is that the pharmacokinetics of THC are much different from ethanol,” the researchers wrote.

The authors noted that alcohol generally cannot be detected 1 to 2 days after last ingestion, whereas THC can be measured up to 30 days after last use because of its lipophilic nature.

To generate the data, researchers studied 190 heavy consumers who were instructed to abstain for 48 hours. Following that several day period, the participants’ blood THC concentrations were measured both before and after cannabis consumption to establish baselines. They were also observed using a driving simulator.

“Current cannabis blood concentrations used to identify impaired drivers could land innocent people in jail,” the Association for Diagnostics & Laboratory Medicine, which publishes the journal that the study appeared in, said in a press release.

“Cannabis blood limit laws lack scientific credibility and are not an accurate determinant of when drivers should face criminal charges or not.”

The authors of the study concluded that “more work needs to be done to address how to best identify drivers who are under the influence of cannabis and are unsafe to drive.”

“Despite evidence showing no correlation between the detection of THC in the blood and driving impairment, 6 states in the United States have per se laws using 2 or 5 ng/mL of THC as the cut-off point for driving under the influence of cannabis, while 12 have a zero-tolerance law,” the journal’s press release says.

The authors, affiliated with the University of California, San Diego and the Center for Medicinal Cannabis Research cautioned that additional research is needed, saying “at present, the best protocol is a combination of observations in the field and toxicology testing.”

A separate study last year found “no support that marijuana legalization increased tolerant behaviors and attitudes toward driving after marijuana use.” Authored by researchers at Nationwide Children’s Hospital and Ohio State University, the study used data from a national traffic safety survey.

Earlier this year, President Donald Trump’s now-confirmed nominee to lead a key federal traffic safety agency said he’s prepared to “double down” on increasing awareness about the risk of marijuana-impaired driving in partnership with the White House.

California Officials Award $30 Million In Marijuana Revenue To Support Research On THC Drinks, Terpenes And Tribal Cannabis Sales

California officials have awarded nearly $30 million in grants for marijuana-focused academic research projects.

The government-funded studies will focus on issues such as cannabis use by older people, the effects of THC beverages, the therapeutic potential of novel cannabinoids, how compounds like terpenes affect product flavoring, tribal participation in the legal market and the environmental impact of marijuana licensing programs.

This marks the third round of grants delivered through the program—which is funded by marijuana tax revenue—raising the total distributions to about $80 million.

The Department of Cannabis Control (DCC) said it prioritized proposals in research areas including educational methods of improving public health and safety, crop yields, state and local marijuana policies, consumer preferences, environmental sustainability and other topics.

“All research findings will be made available at no cost to the public to support broad access to rigorous, science-backed research while contributing to the national understanding of cannabis,” the department said in a press release on Monday.

“DCC received 149 proposals,” it said. “Funding decisions were based on researchers demonstrating strong scientific methodologies, the potential of their research to improve public understanding of cannabis and its effects, and to inform future policymaking.”

Here are some examples of grant awardees and their research initiatives:

• UC San Diego: Cannabis Use and Product Selection Among Older Adults. This study seeks understanding of how older adults weigh product features like potency, cost, and safety when purchasing cannabis. Findings will inform labeling, education, and retail strategies to improve consumer safety and support evidence-based cannabis policy for aging populations. ($643,428)

• UC San Francisco: Clinical pharmacology of commercially available THC-infused beverages. This study will measure THC absorption, onset, and duration across multiple infused-beverage formulations under real-world consumption conditions. Results will inform product safety standards, labeling accuracy, and consumer guidance for low-dose beverage products to minimize impairment risks. ($1,975,523.03)

• UC Davis: Pathways to Partnership with the Tribal Cannabis Market. This study will examine California’s tribal cannabis markets and identify models for tribal–state collaboration. The project will produce regulatory templates and partnership pathways to enhance consumer safety, environmental sustainability, and economic opportunities while respecting tribal sovereignty.  ($698,537)

• UC San Francisco: Cannabinoids and the brain: Focused investigations of therapeutic application and early-life risk. This project will examine how exposure to specific cannabinoids affects brain development, neuroinflammation, and therapeutic pathways. The work will clarify safe dosage thresholds and long-term neurological risks, advancing cannabinoid-based medicine and public health protection. ($1,993,986.41)

• UC Los Angeles: Cannabinoid Therapeutics: Synthesis, Binding, Safety, and Computations. This project will study and characterize novel cannabinoids with therapeutic potential. ($2,000,000)

• UC San Diego: Price and Tax Trends and Their Effects on Cannabis Sales: Evidence from Multi-State Retail Scanner Data. Using comprehensive retail scanner data across 20+ U.S. states, this project will analyze consumer responsiveness to price changes and tax rates, providing actionable insights to guide equitable, health-oriented taxation policies. ($1,219,052)

• UC Berkeley: Cannabis Crop Yields: Survey & Remote Sensing. This project will estimate cannabis crop yield variability across indoor, outdoor, and mixed-light cultivation systems. The resulting models will improve crop-production estimates and inform regulatory oversight and market forecasting for California’s legal cannabis sector. ($1,807,977)

• UC Los Angeles: Characterization of Naturally Occurring Organoleptic Compounds for Inhalable Cannabis Regulation. This study will build a Flower Flavor-Compound Reference Dataset defining natural terpene concentration ranges to distinguish authentic plant flavors from prohibited additives, supporting DCC policy and consumer safety. ($1,234,746)

• San Diego State: Pesticide and Allergen Exposure Among Cannabis Workers: An Occupational Health Study. Through a community-based field study of 150 participants, this research uses silicone wristbands for passive chemical sampling and advanced analysis to assess pesticide and terpene exposure among cannabis workers across cultivation types. Results will provide the first comprehensive exposure profile for California’s cannabis workforce, guiding occupational health protections and regulatory enforcement. ($1,157,196)

• UC Berkeley: Assessing the Environmental Benefits of Cannabis Licensure. This study compares licensed and unlicensed cultivation sites to quantify improvements in water, habitat, and pesticide management following licensure.  ($731,754)

One of the earlier rounds, in 2023, focused on studies investigating novel cannabinoids like delta-8 THC, the genetics of “legacy” strains from the state and monopolies and unfair competition in the market.

Meanwhile, in May, the Governor’s Office of Business and Economic Development (GO-Biz) announced the recipients of over $52 million in community reinvestment grants to nonprofits and local health departments, also funded by marijuana tax revenue.

That marked the seventh round of cannabis-funded California Community Reinvestment Grants (CalCRG) under the state program.

Legalization in California has created a number of new grant programs aimed at addressing the consequences of marijuana prohibition and attempting to nurture a strong, well-regulated legal industry.

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Meanwhile, in October the governor of California vetoed a bill that would have allowed certain marijuana microbusinesses to ship medical cannabis products directly to patients via common carriers like FedEx and UPS, stating that the proposal “would be burdensome and overly complex to administer.”

Also that month, Gov. Gavin Newsom (D) signed a bill aimed at streamlining research on marijuana and psychedelics.

In September, the governor also signed legislation into law to put a pause on a recently enacted tax hike on marijuana products.