Title- Genomic landscape of squamous cell carcinoma- Different genetic pathways culminating in a common phenotype.

INTRODUCTION: Squamous cell carcinomas (SqCCs) are the most common solid tumors in humans and are found across multiple organ systems. Although, integrated analysis of genetic alterations divulge similarities between SqCCs from various body sites, certain genes appear to be more frequently mutated in a given SqCC. These subtle differences may hold the key to determining the differentiation characteristics and predicting aggressiveness of tumors. MATERIALS AND METHOD: Fifty-four cases of SqCCs, in which the primary location of the tumor could be ascertained by clinical and radiological findings, were included in this study. Next generation sequencing data was analyzed for recurrent genetic abnormalities. RESULTS: Genetic alterations were found in 219 genes in the 54 cases studied. TP53 mutations were found to be more frequent in pulmonary SqCCs (86.5%) as compared to non-pulmonary SqCCs (58.8%) (p<0.05). NOTCH gene family mutations and CREBBP mutations were limited to non-pulmonary SqCC (p<0.005) and were mutated in 41.2% and 17.6% cases. CONCLUSION: A detailed comparative analysis of the genetic alterations identified by sequencing identified higher frequency of TP53 mutations in lung SqCCs as compared to non-pulmonary SqCCs. NOTCH and CREBPP mutations were found to be absent in lung and head and neck SqCCs and more frequent in SqCCs from other locations.

Sexual dimorphism in inflammasome-containing extracellular vesicles and the regulation of innate immunity in the brain of reproductive senescent females.

A woman's risk for stroke increases exponentially following the onset of menopause; however, the underlying mechanisms responsible for the increased risk remain unknown. The depletion of endogenous estrogen at menopause is known to activate the inflammatory response. Therefore, in this study we have used reproductively senescent (RS) rats to test the hypotheses that (1) inflammasome activation is significantly higher in the brain of RS females (RSF) as compared to their younger counterparts and age-matched senescent male rats, and that (2) RS triggers an innate immune response mediated in part by inflammasome-containing extracellular vesicles (EV) that originate in the female reproductive organs and then spreads to the brain. We tested these hypotheses using male and female Sprague-Dawley rats (Young: 6-7 months and RS: 9-13 months). Hippocampus, gonads and serum were collected. Additionally, cerebrospinal fluid (CSF) of pre- and post-menopausal women (ages 23 to 37 and 52 to 68) was purchased and extracellular vesicles (EV) were isolated from serum and CSF. The Inflammasome proteins caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and IL-1ß were then resolved by immunoblotting. We found that inflammasome protein expression increased significantly in the analyzed tissues in RSF as compared to young females (YF), such difference was not present in age-matched male rat brains. Interestingly, we found that Nik-related kinase (NRK), which is present in female reproductive organs was present in the CSF and serum-derived EV, suggesting that the source of the EV seen in the brain during RS/menopause originate, in part, in the female reproductive organs. Thus, this study shows for the first time an involvement of the inflammasome originating in the female reproductive system as a contributor to inflammation in the brain that makes the peri-menopausal women's brain more susceptible to neurodegenerative diseases such as stroke.

Contribution of the inflammasome to inflammaging.

BACKGROUND: Inflammation is a natural part of the aging process. This process is referred to as inflammaging. Inflammaging has been associated with deleterious outcomes in the aging brain in diseases such as Alzheimer's disease and Parkinson's disease. The inflammasome is a multi-protein complex of the innate immune response involved in the activation of caspase-1 and the processing of the inflammatory cytokines interleukin (IL)-1ß and IL-18. We have previously shown that the inflammasome plays a role in the aging process in the brain. In this study, we analyzed the brain of young (3 months old) and aged (18 months old) mice for the expression of inflammasome proteins. RESULTS: Our findings indicate that the inflammasome proteins NLRC4, caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and IL-18 are elevated in the cytosol of cortical lysates in aged mice when compared to young. In addition, in the cytosolic fraction of hippocampal lysates in aged mice, we found an increase in NLRC4, caspase-1, caspase-11, ASC and IL-1ß. Moreover, we found higher levels of ASC in the mitochondrial fraction of aged mice when compared to young, consistent with higher levels of the substrate of pyroptosis gasdermin-D (GSDM-D) and increased pyroptosome formation (ASC oligomerization). Importantly, in this study we obtained fibroblasts from a subject that donated his cells at three different ages (49, 52 and 64 years old (y/o)) and found that the protein levels of caspase-1 and ASC were higher at 64 than at 52 y/o. In addition, the 52 y/o cells were more susceptible to oxidative stress as determined by lactose dehydrogenase (LDH) release levels. However, this response was ameliorated by inhibition of the inflammasome with Ac-Tyr-Val-Ala-Asp-Chloromethylketone (Ac-YVAD-CMK). In addition, we found that the protein levels of ASC and IL-18 are elevated in the serum of subjects over the age of 45 y/o when compared to younger subjects, and that ASC was higher in Caucasians than Blacks and Hispanics, whereas IL-18 was higher in Caucasians than in blacks, regardless of age. CONCLUSIONS: Taken together, our data indicate that the inflammasome contributes to inflammaging and that the inflammasome-mediated cell death mechanism of pyroptosis contributes to cell demise in the aging brain.