Immunomodulatory effects of Huaier granule in cancer therapy: a meta-analysis of randomized controlled trials

Abstract Background This meta-analysis aimed to summarize the immunomodulatory effect of Huaier (Trametes robiniophila Murr) granule as adjuvant therapy in patients with cancer. Materials and methods Two authors conducted a search for literature indexed on various databases including PubMed, Embase, Cochrane Library, CNKI, Sinomed, VIP, and WanFang. Randomized controlled trials (RCTs) that investigated the immunomodulatory effect of Huaier granule as adjuvant therapy in cancer patients were included. The outcome of interest included T-lymphocyte subsets (CD3+, CD4+, CD8+ and CD4+/CD8+), immunoglobulin (IgA, IgG, IgM), and natural killer (NK) cells. Results We identified 29 RCTs involving a total of 2206 cancer (including hepatocellular, breast, gastric, colorectal, lung, or nasopharyngeal carcinoma) patients. Compared with conventional treatment alone, Huaier combined conventional treatment significantly improved CD3+ (mean difference [MD] 6.95; 95% confidence intervals [CI] 4.42–9.48), CD4+ (MD 5.53; 95%CI 4.22–6.83), CD4+/CD8+ (MD 0.35; 95%CI 0.25–0.45), IgA (standardized mean difference [SMD] 1.18; 95%CI 0.44–1.93), IgG(SMD 1.71; 95%CI 1.11–2.30), IgM (SMD 0.83; 95%CI 0.59–1.07), and NK cells (MD 5.01; 95%CI 3.61–6.40). However, the effect of Huaier on CD8+ (MD − 1.35; 95%CI − 2.80 to 0.11) was not statistically significant between the groups. Conclusions Huaier granule as adjuvant therapy may significantly improve immune function in patients with cancers. However, additional well-designed RCTs are needed to validate the current findings considering the methodological flaws of the analyzed trials.