dronabinol and nabilone (1985) for their use to control nausea in cancer patients

undergoing chemotherapy (Walsh et al. 2003). Cannabinoids are antiemetics that act

via activation of CB1 receptors in both CNS and ENS and can improve the quality of

life for cancer patients with CINV.

12.5.4.2 Appetite Stimulation

Majority of cancer patients experience loss of appetite and weight loss. The reason

behind this is accumulation of pro-inflammatory cytokines and neuro-hormonal

alterations. Appetite is regulated by hypothalamic region of the brain through

production of peptides (orexigenic and anorectic peptides). Studies have provided

the better understanding regarding the involvement of endocannabinoid system that

might modulate the food uptake via CB1 receptors, which are present in the

hypothalamus. It has been reported that cannabinoids can stimulate appetite in

animal models. The role of THC as appetite stimulant was demonstrated in a study

by Vincent et al. (1983). Dronabinol is an FDA-approved drug for treatment of

appetite and weight loss in patients with HIV/AIDS.

12.5.4.3 Inhibition of Pain

Almost all the cancer patients deal with chronic pain varying from moderate to

severe. This pain originates from the inflammatory response, occurring at the site of

tumor which leads to the induction of nociceptive ligands (Cannabinoids 2003).

Then these nociceptive ligands interact with nociceptors (receptors) due to which

release of neurotransmitters occurs and thus pain arises. Administration of

cannabinoids can suppress pain by inhibiting nociceptive neurotransmission via

CB1 receptor activation (Starowicz et al. 2013). In European countries, Sativex is

prescribed by physicians for its analgesic affects (Bifulco and Pisanti 2015). Pain has

negative impact on the quality of life of cancer patients, which could be improved by

cannabinoids.

12.5.4.4 Psychological Changes

Cannabinoids at low dose can produce anti-anxiety effects. They can contribute in

improving patient’s quality of life by uplifting the mood. THC and nabilone help in

reducing depression and anxiety and improving sleep (Cannabinoids 2003).

The investigations on cannabinoid receptors are primarily focused toward their

use in the treatment of chemotherapy-related adverse effects. However, there are

many preclinical studies that are focused on anticancer role of cannabinoids in

different cancers. It becomes a pre-requisite to understand the mechanism of action

of ECS modulators with respect to a specific pathological condition.

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