The brain-network correlates of personality traits in major depressive disorder (MDD) have not yet been investigated. Furthermore, it is still unclear whether personality traits relate to the depressive episode. This study assessed network properties, depression severity, and personality traits in patients with MDD (n=25) compared with age- and sex-matched healthy controls (n=22). MDD patients with different character traits exhibited significant differences in terms of depression diagnosis and severity of Hamilton Depression Rating Scale scores compared to the controls. The MDD patients also exhibited reduced resting state network activity between the posterior default mode network, right putamen, and right frontal pole, while self-directness (SD) was significantly less frequently diagnosed in MDD patients. In evaluating the network correlates, differences in the SD traits were significantly associated with critical brain network alterations that were not evident in other traits. To the best of our knowledge, this is the first study to provide preliminary evidence of an anomalous connectome in the SD trait in MDD, thus providing strong evidence for personalized antidepressant treatment strategies in MDD.

Background: Immunomodulatory peptides are capable of stimulating or suppressing the immune system. Hence, deregulation of them can be considered as an immunotherapy approach. These peptides may have dual behavior in response to different infections. For instance, an antimicrobial peptide may act as an anticancer, tumor marker or even cause cancer progression. Methods: In this study, we used single-cell RNA sequencing analysis to investigate the deregulation of immunomodulatory peptides in malignant versus normal human breast epithelial cells. We validated the obtained results in chromatin accessibility level. Furthermore, we used a drug repositioning approach to change the expression of these peptides based on their role in cancer biology. Results: As a result, ten immunomodulatory peptides were upregulated in breast cancer versus normal. Chromatin was more accessible for these peptides in cancer cell lines versus normal. Among these ten peptides, five of them were tumor drivers (i.e., BST2, GAPDH, S100A8, S100A9 and HMGB1), three of them were anticancer (i.e., H2AFJ, SCGB2A1 and HMGN2), S100A7 had dual behavior in different cancers and ZG16B was a tumor marker. Using the LINCS L1000 database, we proposed a list of drugs that can deregulate the candidate peptides according to their role in the progression of malignancy. Conclusions: In conclusion, immunomodulatory peptides can be considered as drug targets based on their role in cancer biology.