Red-emitting FIT-PNAs: "On site" detection of RNA biomarkers in fresh human cancer tissues.

To date, there are limited approaches for the direct and rapid visualization (on site) of tumor tissues for pathological assessment and for aiding cytoreductive surgery. Herein, we have designed FIT-PNAs (forced-intercalation-peptide nucleic acids) to detect two RNA cancer biomarkers. Firstly, a lncRNA (long noncoding RNA) termed CCAT1, has been shown as an oncogenic lncRNA over-expressed in a variety of cancers. The latter, an mRNA termed KRT20, has been shown to be over-expressed in metastases originating from colorectal cancer (CRC). To these FIT-PNAs, we have introduced the bis-quinoline (BisQ) cyanine dye that emits light in the red region (605-610 nm) of the visible spectrum. Most strikingly, spraying fresh human tissue taken from patients during cytoreductive surgery for peritoneal metastasis of colon cancer with an aqueous solution of CCAT1 FIT-PNA results in bright fluorescence in a matter of minutes. In fresh healthy tissue (from bariatric surgeries), no appreciable fluorescence is detected. In addition, a non-targeted FIT-PNA shows no fluorescent signal after spraying this FIT-PNA on fresh tumor tissue emphasizing the specificity of these molecular sensors. This study is the first to show on-site direct and immediate visualization of an RNA cancer biomarker on fresh human cancer tissues by topical application (spraying) of a molecular sensor.

Adaptation of couples living with a high risk of breast/ovarian cancer and the association with risk-reducing surgery.

Women who carry BRCA1/2 mutations have a significantly elevated risk for breast and ovarian cancer. The positive test result and subsequent decisions about risk reducing behaviors can evoke distress, anxiety and worry. Psychological adaptation, or the process of coming to terms with the implications of a health threat, is an understudied construct in BRCA1/2 carriers. Little is known about adaptation and how it relates to other aspects of living at high risk for cancer. Even less is understood about adaptation among partners of BRCA1/2 carriers, and its relationship to adaptation in high risk individuals. Women at increased risk of breast/ovarian cancer (N = 103) and a subset of partners (N = 39) completed questionnaires that assessed risk management decisions (e.g. screening, risk-reducing surgery), dyadic coping, and the outcome of psychological adaptation. Women who had undergone risk-reducing mastectomy (RRM) had significantly higher levels of adaptation than those who had not (t = 5.5, p < 0.001, d = 1.10). Partners of women who had undergone RRM also had higher levels of adaptation than partners of women who had not undergone RRM (t = 3.7, p = 0.01, d = 0.96), though this association was not statistically significant when controlling for carriers' adaptation. Undergoing risk-reducing oophorectomy was not associated with adaptation for BRCA1/2 carriers or their partners. Risk-reducing mastectomy is a significant event in the process of adapting to life at risk for hereditary cancer. Further, adaptation among partners is highly related to adaptation in carriers. These results aid in the understanding of the experience of couples living with cancer risk and the medical decisions related to adaptation.

Genes with a Combination of Over-Dominant and Epistatic Effects Underlie Heterosis in Growth of Saccharomyces cerevisiae at High Temperature.

Heterosis describes a phenotypic phenomenon of hybrid superiority over its homozygous parents. It is a genetically intriguing phenomenon with great importance for food production. Also called hybrid-vigor, heterosis is created by non-additive effects of genes in a heterozygous hybrid made by crossing two distinct homozygous parents. Few models have been proposed to explain how the combination of parental genes creates an exceptional hybrid performance. Over-dominant mode of inheritance is an attractive model since a single gene can potentially create the heterotic effect, but only a few such loci have been identified. To a collection of 120 hybrids, made by crossing 16 divergent Saccharomyces cerevisiae yeast strains, we applied a method for mapping heterozygous loci that non-additively contribute to heterotic growth at 37°. Among 803 candidate loci that were mapped, five were tested for their heterotic effect by analyzing backcrosses and F2 populations in a specific hybrid background. Consistently with the many mapped loci, specific analyses confirmed the minor heterotic effect of the tested candidate loci. Allele-replacement analyses of one gene, AEP3, further supported its heterotic effect. In addition to over-dominant effects, the contribution of epistasis to heterosis was evident from F2 population and allele-replacement analyses. Pairs of over-dominant genes contributed synergistically to heterosis. We show that minor over-dominant effects of multiple genes can combine to condition heterosis, similarly to loci affecting other quantitative traits. Furthermore, by finding of epistatic interactions between loci that each of them individually has an over-dominant effect on heterosis, we demonstrate how hybrid advantage could benefit from a synergistic combination of two interaction types (over-dominant and synergistic epistatic). Thus, by portraying the underlying genetic complexity, these findings advance our understanding of heterosis.