The understanding of the molecular mechanisms of the immune tolerance induced by the tumoral microenvironment is fundamental to prevent cancer development or to treat cancer patients using immunotherapy. Actually, there are investigations about “addressed‐drugs” against cancer cells without affecting normal cells. It could be ideal to find selective and specific compounds that only recognize and destroy tumor cells without damaging the host normal cells. For thousands of years, mushrooms have been used for medicinal purposes because of their curative properties. D‐Fraction, an extract of Maitake (from the edible Grifola frondosa mushroom), rich in β‐glucans, exert notable effects in the immune system. Until now, some published articles suggest that Maitake D‐Fraction could have anti‐tumoral activity, prevent oncogenesis and metastasis in some tumor types. However, there are no clear data about Maitake D‐Fraction action on breast cancer prevention and its exact molecular mechanisms are not yet elucidated. The experiments were performed employing 25 female BALBc mice that were treated with and without Maitake D‐Fraction Pro4X or Maitake Standard for 15 days by daily intraperitoneal injection. After treatment period, all mice were implanted with murine tumor cells LM3 to induce mammary tumorigenesis. Animals were checked weekly and killed after 46 days of LM3 transplant; percentage of cancer prevention, rate of tumor growing, and overall survival were determined. Under dissection, the internal organs were evaluated histologically and genetically by RT‐PCR. We found that 5 mg/kg per day of Maitake D‐Fraction Pro4X, administered dairy during 15 days to BALBc mice was able to block more than 60% breast cancer development. However, Maitake Standard prevents oncogenesis in 26% to respect control. In this work, we found that Maitake D‐Fraction Pro4X, administered to BALBc mice, prevents breast carcinogenesis, block tumor invasiveness, reduce angiogenesis, and increase overall survival.

Breast cancer is the most common type of cancer in females in Argentina, with an incidence rate similar to that in the USA. However, the contribution of the BRCA1 or BRCA2 mutation in breast cancer incidence has not yet been investigated in Argentina. In order to evaluate which BRCA1 polymorphisms or mutations characterize female breast cancer in Argentina, the current study enrolled 206 females with breast cancer from several hospitals from the southeast of Argentina. A buccal smear sample was obtained in duplicate from each patient and the DNA samples were processed for polymorphism analysis using the single-strand conformational polymorphism technique. The polymorphisms in BRCA1 were investigated using a combination of 15 primers to analyze exons 2, 3, 5, 20 and 11 (including the 11.1 to 11.12 regions). The BRCA1 mutations were confirmed by direct sequencing. Samples were successfully examined from 154 females and, among these, 16 mutations were identified in the BRCA1 gene representing 13.9% of the samples analyzed. One patient was identified with a polymorphism in exon 2 (0.86%), four in exon 20 (3.48%), four in exon 11.3 (3.48%), one in exon 11.7 (0.86%), two in exon 11.8 (1.74%), one in exon 11.10 (0.86%) and one in exon 11.11 (0.86%). The most prevalent alteration in BRCA1 was located in exon 11 (11 out of 16 patients; 68.75%). The objective of our next study is to evaluate the prevalence of mutations in the BRCA2 gene and analyze the BRCA1 gene in the healthy relatives of BRCA1 mutation carriers.

Background: Conventional treatments for breast cancer involve surgery followed by radiation and hormonal therapy and/or chemotherapy. Some of these treatments have toxic side effects. Because drugs used in chemotherapy affect both cancer and normal cells to varying degrees, researchers are currently developing targeted drugs that only attack cancer cells without affecting normal cells. One approach to this is to found compounds that are more selective and specific, destroying only tumour cells and prevent metastases without harming normal cells. For thousands of years, medicinal mushrooms have been used because of their healing properties. Maitake (Grifola frondosa) is one of the most promising edible and medicinal mushroom, acting promoting the immune system against the tumorigenesis process.