Signatures of post-zygotic structural genetic aberrations in the cells of histologically normal breast tissue that can predispose to sporadic breast cancer

Sporadic breast cancer (SBC) is a common disease without robust means of early risk prediction in the population. We studied 282 females with SBC, focusing on copy number aberrations in cancer-free breast tissue (uninvolved margin, UM) outside the primary tumor (PT). In total, 1162 UMs (1–14 per breast) were studied. Comparative analysis between UM(s), PT(s), and blood/skin from the same patient as a control is the core of the study design. We identified 108 patients with at least one aberrant UM, representing 38.3% of cases. Gains in gene copy number were the principal type of mutations in microscopically normal breast cells, suggesting that oncogenic activation of genes via increased gene copy number is a predominant mechanism for initiation of SBC pathogenesis. The gain of ERBB2, with overexpression of HER2 protein, was the most common aberration in normal cells. Five additional growth factor receptor genes (EGFR, FGFR1, IGF1R, LIFR, and NGFR) also showed recurrent gains, and these were occasionally present in combination with the gain of ERBB2. All the aberrations found in the normal breast cells were previously described in cancer literature, suggesting their causative, driving role in pathogenesis of SBC. We demonstrate that analysis of normal cells from cancer patients leads to identification of signatures that may increase risk of SBC and our results could influence the choice of surgical intervention to remove all predisposing cells. Early detection of copy number gains suggesting a predisposition toward cancer development, long before detectable tumors are formed, is a key to the anticipated shift into a preventive paradigm of personalized medicine for breast cancer.

Prevalence and correlates of being bullied among in-school adolescents in Malawi: results from the 2009 Global School-Based Health Survey

BACKGROUND

Physical and emotional violence against adolescents is a neglected, but growing problem globally. Violence against adolescents negatively affects the victim in terms of physical health, school attendance and performance and social adjustment. The literature on the prevalence and associated factors of bullying against adolescents is sparse in southern Africa outside South Africa. Such data are even sparser for Malawi. The current study was conducted to estimate the prevalence of self-reported bullying and its personal and social correlates.

METHODS

A secondary analysis of the Malawi School-Based Student Health Survey (2009) was done. Descriptive analyses were done to describe the sample and estimate the prevalence of reporting history of bullying in the past 30 days preceding the survey. Logistic regression analysis was done to assess the association between several factors and being a victim of bullying. Crude and adjusted odds ratios are reported.

RESULTS

A total of 2,264 in-school adolescents participated in the Malawi School-Based Student Health Survey of 2009. Just under half (44.5%) reported having been bullied in the previous month to the survey (44.1% among boys versus 44.9% among girls). Compared to adolescents of age 16 years or older, those who were 12 years old or younger and those who were 14 years of age were more likely to be bullied (AOR=1.54; 95% CI [1.41, 1.76]) and OR=1.26; 95% CI [1.21, 1.31]) respectively. The other risk factors that were identified in the analysis were loneliness (AOR = 2.23; 95% CI [2.20, 2.27]), and being worried (AOR = 2.80; 95% CI [2.76, 2.85[). Adolescents who had no close friends were 14% (AOR = 1.14; 95% CI [1.11-1.17]) more likely to be reporting bullied compared to adolescents who reported having close friends. Adolescents who smoked cigarettes were more than three times more likely to reporting be bullied compared to non-smokers (AOR=3.97; 955 CI [3.83, 4.10]), while those who drank alcohol were more than twice as likely to be bullied as adolescents who did not take alcohol (AOR=2.26; 95% CI [2.16, 2.35]).

CONCLUSION

Malawian in-school adolescents report a high prevalence of having been bullied. Traditional associated factors such alcohol and smoking as well as emotional correlates (loneliness, worry) were associated with being a victim of bullying. School officials and health workers caring for adolescents should be sensitized to the frequent occurrence of bullying and to its correlates and consequences.