Uwafuji S, Goi T, Naruse T, Kurebayashi H, Nakazawa T, Hirono Y, Yamaguchi A (2013). Protein-bound polysaccharide K reduced the invasive ability of colon cancer cell lines. Anticancer Research 33, 4841-4845.

BACKGROUND/AIM: A protein-bound polysaccharide, polysaccharide K (PSK), is a non-specific immunological agent used in the treatment of colon cancer, however few studies have investigated the genetic changes in cancer cells treated with PSK. Therefore, we investigated the effect of PSK on cancer cell invasion, which is an indicator for the malignancy of colon cancer cell lines, and performed additional genetic analyses.
MATERIALS AND METHODS: We performed Matrigel invasion assay to examine whether the invasive ability of colon cancer cell lines HT29, HCT116, and LoVo would be impacted upon stimulation with PSK. We used reverse transcription-polymerase chain reaction (RT-PCR) to evaluate for changes in the expression of matrix metalloproteinases (MMP)-2 and - 9 upon stimulation of colon cancer cell lines with PSK.
RESULTS: The mean number of invasive cells in untreated HCT116, HT29, and LoVo cells was 146, 81, and 65, respectively, while that in PSK-treated cell lines was reduced to 24, 7, and 4, respectively. mRNA levels of MMP2 and MMP9 in PSK-stimulated cell lines were significantly lower than those in unstimulated cell lines.
CONCLUSION: PSK reduced the expression of MMP2 and MMP9 mRNAs and cell invasion of this panel of colon cancer cell lines.


Ohwada S, Ogawa T, Makita F, Tanahashi Y, Ohya T, Tomizawa N, Satoh Y, Kobayashi I, Izumi M, Takeyoshi I, Hamada K, Minaguchi S, Togo Y, Toshihiko T, Koyama T, Kamio M (2006). Beneficial effects of protein-bound polysaccharide K plus tegafur/uracil in patients with stage II or III colorectal cancer: analysis of immunological parameters. Oncol Rep 15:861-8.

Protein-bound polysaccharide K (PSK) increased the 5-year disease-free survival rate and reduced the risk of recurrence in a randomised, controlled study for stage II and III colorectal cancer. In order to elucidate the disease-free survival benefits with PSK and what immunological markers could indicate a PSK responder, serial changes in immunological parameters were monitored in the study. PSK decreased the mean serum immunosuppressive acidic protein (IAP) level, and increased the mean population of natural killer (NK) cells compared with the controls. The 5-year disease-free and overall survival rate for patients with serum IAP values <or=500 microg ml(-1), which represents the normal value, were 75.5% (95% CI: 66.8-84.2%; p=0.016) and 85.1% (95% CI: 77.9-92.3%; p=0.032), respectively, in the PSK group compared with 57.5% (95% CI: 43.3-71.6%) and 70.2% (95% CI: 57.1-83.3%) in the control group. In patients with NK cell population >or=8% at 3 months after surgery, PSK conferred a significantly better (p=0.038) 5-year disease-free survival (86.7%; 95% CI: 74.5-98.8%) compared to the control group (60.0%; 95% CI: 29.6-90.4%). In the proportional hazards model, the presence of regional metastases (relative risk, 3.595; 95% CI: 1.518 to 8.518; p=0.004) and omission of PSK treatment (relative risk, 3.099; 95% CI: 1.202 to 7.990; p=0.019) were significant indicators of recurrence. PSK acts as an immunomodulatory activity and biochemical modulator in stage II or III colorectal cancer. Pre-operative serum IAP values <or=500 microg ml(-1) and an NK cell population >or=8% at 3 months after surgery are possible PSK response predictors.


Eliza WL, Fai CK, Chung LP (2012). Efficacy of Yun Zhi (Coriolus versicolor) on survival in cancer patients: systematic review and meta-analysis. Recent Pat Inflamm Allergy Drug Discov 1:78-87.

AIM: Patients with cancer frequently use herbs along with the conventional medical treatment, hoping to enhance recovery. Mushrooms have an established history of use in traditional oriental therapies. In Asian cultures, mushrooms are combined with herbal mixtures to treat cancer. This systematic review and meta-analysis draw from randomized, placebo-controlled, double-blind trials to assess the efficacy of Yun Zhi (YZ) for survival in cancer patients.
MATERIAL & METHODS: Systematic review and meta-analysis technique were used to aggregate and analyze the efficacy of Yun Zhi on survival in cancer patients from 13 clinical trials using computerized database and manual search.
RESULTS: The findings show that Yun Zhi results in a significant survival advantage compared with standard conventional anti-cancer treatment alone. Of patient randomized to Yun Zhi, there was a 9% absolute reduction in 5-year mortality, resulting in one additional patient alive for every 11 patients treated. In patients with breast cancer, gastric cancer, or colorectal cancer treated with chemotherapy, the effects of the combination of Yun Zhi preparation on the overall 5-year survival rate was more evident, but not in esophageal cancer and nasophayngeal carcinoma. However, subgroup analysis could not conclude which type of anti-cancer treatment may maximize the benefit from Yun Zhi.
CONCLUSION: This meta-analysis has provided strong evidence that Yun Zhi would have survival benefit in cancer patients, particularly in carcinoma of breast, gastric and colorectal. Nevertheless, the findings highlight the need for further evidence from prospective studies of outcome to guide future potential modifications of treatment regimes. Recent patents on the use of mushrooms for the treatment of cancer are also summarized in this review.