Epigenetic information is frequently erased near the start of each new generation (1). In some cases, however, epigenetic information can be transmitted from parent to progeny (epigenetic inheritance) (2). A particularly striking example of epigenetic inheritance is dsRNA-mediated gene silencing (RNAi) in C. elegans, which can be inherited for more than five generations (3–8). To understand this process we conducted a genetic screen for animals defective for transmitting RNAi silencing signals to future generations. This screen identified the gene heritable RNAi defective (hrde)-1.
hrde-1 encodes an Argonaute (Ago) that associates with small interfering (si)RNAs in germ cells of the progeny of animals exposed to dsRNA. In nuclei of these germ cells, HRDE-1 engages the Nrde nuclear RNAi pathway to direct H3K9me3 at RNAi targeted genomic loci and promote RNAi inheritance. Under normal growth conditions, HRDE-1 associates with endogenously expressed siRNAs, which direct nuclear gene silencing in germ cells. In hrde-1 or nuclear RNAi deficient animals, germline silencing is lost over generational time. Concurrently, these animals exhibit steadily worsening defects in gamete formation and function that ultimately lead to sterility. These results establish that the Ago HRDE-1 directs gene-silencing events in germ cell nuclei, which drive multi-generational RNAi inheritance and promote immortality of the germ cell lineage. We propose that C. elegans uses the RNAi inheritance machinery to transmit epigenetic information, accrued by past generations, into future generations to regulate important biological processes.
There is limited high-quality clinical evidence on the safety and effectiveness of IVC. The existing evidence is preliminary and cannot be considered conclusive but is suggestive of a good safety profile and potentially important antitumor activity; however, more rigorous evidence is needed to conclusively demonstrate these effects. IVC may improve the quality of life and symptom severity of patients with cancer, and several cases of cancer remission have been reported. Well-designed, controlled studies of IVC therapy are needed.
BackgroundSoy and red clover isoflavones are controversial due to purported estrogenic activity and possible effects on breast cancer. We conducted a systematic review of soy and red clover for efficacy in improving menopausal symptoms in women with breast cancer, and for potential impact on risk of breast cancer incidence or recurrence.MethodsWe searched MEDLINE, Embase, the Cochrane Library, and AMED from inception to March 2013 for human interventional or observational data pertaining to the safety and efficacy of soy and red clover isoflavones in patients with or at risk of breast cancer. ResultsOf 4179 records, we included a total of 131 articles: 40 RCTs, 11 uncontrolled trials, and 80 observational studies. Five RCTs reported on the efficacy of soy for hot flashes, showing no significant reductions in hot flashes compared to placebo. There is lack of evidence showing harm from use of soy with respect to risk of breast cancer or recurrence, based on long term observational data. Soy intake consistent with that of a traditional Japanese diet (2-3 servings daily, containing 25-50mg isoflavones) may be protective against breast cancer and recurrence. Human trials show that soy does not increase circulating estradiol or affect estrogen-responsive target tissues. Prospective data of soy use in women taking tamoxifen does not indicate increased risk of recurrence. Evidence on red clover is limited, however existing studies suggest that it may not possess breast cancer-promoting effects. ConclusionSoy consumption may be associated with reduced risk of breast cancer incidence, recurrence, and mortality. Soy does not have estrogenic effects in humans. Soy intake consistent with a traditional Japanese diet appears safe for breast cancer survivors. While there is no clear evidence of harm, better evidence confirming safety is required before use of high dose (≥100mg) isoflavones can be recommended for breast cancer patients.
MLT may benefit cancer patients who are also receiving chemotherapy, radiotherapy, supportive therapy, or palliative therapy by improving survival and ameliorating the side effects of chemotherapy.
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