Coix lacryma-jobi (Job's Tears)

Job's Tears (Coix lacryma-jobi) contains coixenolide, a fatty acid ester, and coixol, which modulate immune function and may inhibit tumor cell proliferation via lipid-mediated signaling pathways. Its seed oil extract, commercialized as Kanglaite®, has advanced to FDA-approved Phase II clinical trials for stage IV lung and pancreatic cancers.

Origin & History

Coix lacryma-jobi (Job's tears or adlay) is a tall grass native to Southeast Asia, cultivated for its hard, tear-shaped seeds used as both a cereal crop and traditional medicine. The seeds are processed through various methods including powdering for food and medicine, oil extraction for pharmaceutical preparations like Kanglaite® injection, and methanolic extraction for research purposes.

Historical & Cultural Context

Job's tears has been used in Traditional Chinese Medicine for centuries as Yi Yi Ren to promote diuresis, drain dampness, and treat conditions ranging from edema to cancer. The plant also features prominently in Ayurvedic, Siddha, and Unani-Tibb medicine systems for treating diabetes, rheumatism, and fertility issues.

Health Benefits

• Enhanced antitumor immunity - Small human study (n=7) showed increased peripheral cytotoxic lymphocytes after 4 weeks of supplementation
• Potential cancer growth inhibition - Kanglaite® extract received FDA approval for Phase II trials in stage IV non-small-cell lung cancer and pancreatic cancer (with gemcitabine)
• Anti-inflammatory effects - Animal studies demonstrate COX-2 suppression in lung tumorigenesis models
• Traditional digestive support - Used in TCM to strengthen spleen and stop diarrhea (traditional use evidence only)
• Diuretic and detoxification properties - Traditional use for edema and heat-clearing (traditional use evidence only)

How It Works

Coixenolide, a glycerol triester found in Coix seed oil, is believed to suppress tumor proliferation by inhibiting fatty acid synthase (FASN) and disrupting lipid metabolism in cancer cells. Coixol acts as a skeletal muscle relaxant and mild anti-inflammatory agent by downregulating COX-2 expression and reducing prostaglandin E2 synthesis. Polysaccharide fractions from Job's Tears also stimulate natural killer (NK) cell and cytotoxic T-lymphocyte (CTL) activity, suggesting immunomodulatory effects via Toll-like receptor (TLR) pathways.

Scientific Research

Human clinical evidence remains limited, with no large-scale RCTs or meta-analyses available. The most significant clinical development is Kanglaite® (KLT), a seed oil extract that received FDA approval for Phase II trials in stage IV non-small-cell lung cancer and pancreatic cancer, though specific outcomes and sample sizes were not detailed in the available research.

Clinical Summary

A small human pilot study (n=7) demonstrated that four weeks of Job's Tears supplementation significantly increased peripheral cytotoxic lymphocyte counts, suggesting measurable immunostimulatory effects, though the absence of a control group severely limits interpretation. Kanglaite® injection, derived from Coix seed oil, received FDA Investigational New Drug (IND) approval for Phase II trials in stage IV non-small-cell lung cancer and pancreatic cancer, representing the most clinically advanced application of this ingredient. Preclinical rodent studies have shown tumor weight reduction in sarcoma and hepatoma models, but human randomized controlled trial data remain sparse and underpowered. Overall, the evidence base is preliminary; no large-scale RCT has confirmed efficacy for any indication in humans.

Nutritional Profile

Per 100g of raw Job's Tears (dehulled grain): Energy ~360 kcal; Protein 15–18g (notably higher than polished rice at ~7g; rich in leucine, glutamic acid, and proline; digestibility ~80–85%); Total fat 5–7g (unusually high for a cereal grain, predominantly oleic acid ~50%, linoleic acid ~30%, and palmitic acid ~15%; lipid fraction concentrated in bran layer); Carbohydrates ~62–65g; Dietary fiber 1.5–3g (dehulled) or up to 9–10g (whole grain with bran); Starch ~55–60g (amylose content ~25–30%, contributing to moderate glycemic index ~50–55 for cooked grain). Key micronutrients per 100g: Iron 4–5mg (non-heme; bioavailability enhanced with vitamin C co-consumption); Zinc 3–4mg; Calcium 20–30mg; Phosphorus 280–380mg; Potassium 240–300mg; Magnesium 100–120mg; Manganese ~1.5mg; B-vitamins including Thiamine (B1) 0.28–0.40mg, Riboflavin (B2) 0.15–0.20mg, Niacin (B3) 4–6mg; Vitamin E (tocopherols/tocotrienols) ~3–5mg. Bioactive compounds: Coixenolide (a glyceride-type lipid unique to Coix, present at ~0.1–0.5% of seed weight, considered the primary antitumor-active lipid); Coixol (6-methoxybenzoxazolinone) ~0.01–0.04% in seed, an anti-inflammatory and sedative compound; Coixan A, B, and C (polysaccharides with immunomodulatory properties, total polysaccharide content ~2–5% of dry weight); Trans-ferulic acid and feruloylstigmasterol (phenolic compounds contributing to COX-2 suppression); β-sitosterol and stigmasterol (phytosterols, ~50–100mg/100g total sterols, potentially cholesterol-lowering); Tricin (a flavone found at ~0.5–2mg/100g with demonstrated anti-inflammatory and antiproliferative activity); Polyphenols total ~150–300mg GAE/100g (concentrated in bran/hull layers; bioavailability moderate, improved with thermal processing); Gamma-aminobutyric acid (GABA) present in germinated forms at ~20–40mg/100g. The Kanglaite® injectable extract is a standardized triglyceride fraction (primarily C18:1 and C18:2 fatty acids) extracted from the endosperm lipid. Note: Whole-grain forms with intact bran retain significantly higher fiber, polyphenol, and coixenolide concentrations compared to polished/pearled forms, where 40–60% of bioactives may be lost.

Preparation & Dosage

Clinically studied forms include: Kanglaite® injection (seed oil microemulsion) used in cancer trials with unspecified dosages; Adlay seed tablets at 6 tablets daily for 4 weeks in immunity studies. Traditional use involves consuming seeds as porridge or rice substitute without standardized doses. Consult a healthcare provider before starting any new supplement.

Synergy & Pairings

Reishi mushroom, Astragalus, Green tea extract, Turmeric, Beta-glucans

Safety & Interactions

Job's Tears is generally regarded as safe when consumed as a food grain, but concentrated extracts and injectable forms (Kanglaite®) carry a different risk profile and should only be used under medical supervision. Uterotonic activity has been reported in animal studies, making supplemental doses contraindicated during pregnancy. Potential drug interactions include additive immunomodulatory effects when combined with immunosuppressants such as cyclosporine or corticosteroids, which could unpredictably alter immune responses. Individuals with grain allergies or on anticoagulant therapy should exercise caution, as high-dose seed oil extracts may mildly affect platelet aggregation.