Single nucleotide polymorphisms in noncoding regions of Rad51C do not change the risk of unselected breast cancer but they modulate the level of oxidative stress and the DNA damage characteristics: a case-control study.

Deleterious and missense mutations of RAD51C have recently been suggested to modulate the individual susceptibility to hereditary breast and ovarian cancer and unselected ovarian cancer, but not unselected breast cancer (BrC). We enrolled 132 unselected BrC females and 189 cancer-free female subjects to investigate whether common single nucleotide polymorphisms (SNPs) in non-coding regions of RAD51C modulate the risk of BrC, and whether they affect the level of oxidative stress and the extent/characteristics of DNA damage. Neither SNPs nor reconstructed haplotypes were found to significantly affect the unselected BrC risk. Contrary to this, carriers of rs12946522, rs16943176, rs12946397 and rs17222691 rare-alleles were found to present significantly increased level of blood plasma TBARS compared to respective wild-type homozygotes (p<0.05). Furthermore, these carriers showed significantly decreased fraction of oxidatively generated DNA damage (34% of total damaged DNA) in favor of DNA strand breakage, with no effect on total DNA damage, unlike respective wild-types, among which more evenly distributed proportions between oxidatively damaged DNA (48% of total DNA damage) and DNA strand breakage was found (p<0.0005 for the difference). Such effects were found among both the BrC cases and healthy subjects, indicating that they cannot be assumed as causal factors contributing to BrC development

Scientific opinion on HAA299 (nano)– SCCS/1634/21

From Elsevier via Jisc Publications RouterHistory: accepted 2023-02-15, issued 2023-03-01Article version: AMPublication status: AcceptedOpinion to be cited as: SCCS (Scientific Committee on Consumer Safety), Opinion on HAA299 (nano), preliminary opinion July 22, 2021, final opinion 26–27 October 2021, SCCS/1634/2021. HAA299 is a UV filter active intended to be used in sunscreen products as skin protectant against UVA-1 rays. Its chemical name is ‘2-(4-(2-(4-Diethylamino-2 hydroxy-benzoyl)-benzoyl)-piperazine-1-carbonyl)-phenyl)-(4-diethylamino-2-hydroxyphenyl)-methanone’ and INCI name ‘Bis-(Diethylaminohydroxybenzoyl Benzoyl) Piperazine’ (CAS 919803-06-8). This product was designed and developed to deliver to the consumer stronger UV protection on skin and is most effective as a UV filter when it is milled to a smaller particle size, a process we refer to as micronization. Currently HAA299 normal form and nano form is not regulated under the Cosmetic Regulation (EC) No. 1223/2009. In 2009, Commission' services received a dossier from industry to support the safe use of HAA299 (micronised and non-micronised) in cosmetic products, which was further substantiated with additional information in 2012. In its corresponding opinion (SCCS/1533/14), the SCCS concluded that “the use of non-nano HAA299 (micronised or non-micronised, with median particle size distribution around 134 nm or larger, as measured by FOQELS) at a concentration up to 10% as an UV-filter in cosmetic products, does not pose a risk of systemic toxicity in humans”. In addition, SCCS stated that “[the Opinion] … covers the safety evaluation of HAA299 in non-nano form. The opinion does not cover the safety evaluation of HAA299 which is composed of nano particles' and highlighted that ‘[the Opinion] … does not apply to inhalation exposure of HAA299 since no information on chronic or sub-chronic toxicity after inhalation is provided”. With the current submission, received in September 2020, and in view of the previous SCCS opinion (SCCS/1533/14) on the normal form of HAA299, the applicant requests to assess the safety of HAA299 (nano) intended to be used as UV-filter up to a maximum concentration of 10%

Summary of the analysis of effect of <i>RAD51C</i> SNPs and BrC on DNA damage.

<p>Summary of the analysis of effect of <i>RAD51C</i> SNPs and BrC on DNA damage.</p

Log-transformed levels of total DNA damage (A) and DNA strand breakage (B) expressed as logarithmically-transformed relative amount of DNA in respective comet tails in whole blood leukocytes of healthy controls (solid) and BrC cases (stripes) carrying the respective wild-type (<i>wt-</i>; dark columns) or rare-allele containing (<i>var</i>-; light columns) genotypes.

<p>Only dominant genetic model was assumed. Identification of genotypes as <i>wild-type</i> or rare-allele containing (i.e. heterozygotic and <i>rare</i> homozygotes) with reference to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110696#pone-0110696-t003" target="_blank">Table 3</a>, in which individual genotypes for each SNP are ordered accordingly. Data are presented as means (columns) ± SD (error bars). Logarithmical transformation was employed in order to normalize the distribution of raw comet assay data for the purpose of ANOVA/ANCOVA analysis. Total DNA damage data for <i>wt</i>-controls, <i>var</i>-controls, <i>wt-</i>cases and <i>var</i>-cases, respectively (log-%): <b>rs302874:</b> 0.56±0.17, 0.47±0.24, 0.57±0.16, 0.55±0.19; <b>rs12946522:</b> 0.49±0.23, 0.50±0.25, 0.57±0.17, 0.53±0.19; <b>rs302873:</b> 0.56±0.17, 0.47±0.24, 0.57±0.16, 0.55±0.19; <b>rs16943176:</b> 0.50±0.23, 0.50±0.25, 0.57±0.18, 0.53±0.18; <b>rs12946397:</b> 0.50±0.23, 0.50±0.25, 0.57±0.18, 0.53±0.18; <b>rs17222691:</b> 0.50±0.23, 0.50±0.25, 0.57±0.18, 0.54±0.17; <b>rs28363302:</b> 0.49±0.21, 0.54±0.38, 0.55±0.18, 0.64±0.14. DNA strand breakage data <i>wt</i>-controls, <i>var</i>-controls, <i>wt-</i>cases and <i>var</i>-cases: <b>rs302874:</b> 0.17±0.25, 0.15±0.18, 0.35±0.19, 0.26±0.18; <b>rs12946522:</b> 0.15±0.20, 0.21±0.21, 0.29±0.19, 0.32±0.18; <b>rs302873:</b> 0.17±0.25, 0.15±0.18, 0.35±0.19, 0.27±0.18; <b>rs16943176:</b> 0.14±0.20, 0.21±0.21, 0.29±0.19, 0.32±0.18; <b>rs12946397:</b> 0.14±0.20, 0.21±0.21, 0.29±0.19, 0.31±0.18; <b>rs17222691:</b> 0.14±0.20, 0.21±0.21, 0.29±0.19, 0.32±0.18; <b>rs28363302:</b> 0.17±0.20, 0.06±0.20, 0.28±0.19, 0.40±0.16. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110696#pone-0110696-t005" target="_blank">Table 5</a> for the summary of statistical analysis.</p

The map of LD between seven analyzed SNPs in non-coding regions of <i>RAD51C</i>.

<p>The values in the map are the normalized measures of allelic association |D’| (<b>A</b>) and correlation coefficients (r²) (<b>B</b>) calculated for each pair of SNPs (both provided as percentages). The color scheme represent the corresponding confidence bounds for a given pair of SNPs: black – strong evidence of LD; grey – inconclusive; white – strong evidence of recombination <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110696#pone.0110696-Barrett1" target="_blank">[37]</a>. Solid line indicates the identified 1 kb-long LD block, within which common and rare haplotypes were reconstructed, the frequency of which is provided in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110696#pone-0110696-t003" target="_blank">Table 3</a>. Algorithm employed for LD block identification is described in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110696#s2" target="_blank"><i>Material and Methods</i></a> section.</p

Levels of TBARS (dark columns), DNA strand breakage (grey columns) and total DNA damage (white columns) determined in whole blood samples from BrC cases and healthy control females.

<p>Data presented as medians (columns) and interquartile ranges (whiskers). Levels of TBARS among BrC cases (n = 132) vs. control females (n = 189): 2.6 [2.1–3.3] μM vs. 2.3 [1.8–2.7] μM, p<0.0001, Mann-Whitney <i>U</i> test (***). Levels of DNA strand breakage and total DNA damage were assessed in the whole group of BrC cases and tested for differences against a subset of 40 control subjects randomly selected from the whole control group by means of the age-stratified randomization (<i>see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110696#s2" target="_blank">Materials and Methods</a></i>). DNA strand breakage: BrC cases vs. controls: 2.0 [1.5–2.7] %DNA in comet tail vs. 1.6 [1.1–2.1] %DNA in comet tail, p<0.001, Mann-Whitney <i>U</i> test (**). Total DNA damage: BrC cases vs. controls: 3.5 [2.9–4.6] %DNA in comet tail vs. 3.5 [2.4–4.6] %DNA in comet tail, <i>NS</i>. The age distribution in the control subset was verified to match with the one in the whole control group (<i>see </i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0110696#pone-0110696-t001" target="_blank"><i>Table 1</i></a>). The distribution of TBARS in the randomized subset of 40 controls did not differ significantly from the one observed in the whole control group (1.7 [1.5–2.1] μM vs. 2.3 [1.8–2.7] μM, <i>NS</i>) but differed significantly from the one in the BrC group (1.7 [1.5–2.1] μM vs. 2.6 [2.1–3.3] μM, p<0.001, Kruskal-Wallis <i>H</i>-test post-hoc analysis).</p

The effect of <i>RAD51C</i> SNPs and BrC on ratio of oxidatively generated DNA damage to DNA strand breakage.

<p>The effect of <i>RAD51C</i> SNPs and BrC on ratio of oxidatively generated DNA damage to DNA strand breakage.</p

Resume of <i>RAD51C</i> SNPs analyzed in the study.

<p>Resume of <i>RAD51C</i> SNPs analyzed in the study.</p