Molecular and toxicological mechanisms behind the effects of chromium (VI) on the male reproductive system of Mytilus galloprovincialis: First evidence for poly-ADP-ribosylation of protamine-like II.

Studies on the molecular mechanisms of heavy metal toxicity in invertebrate reproduction are limited. Given that PARP-catalysed ADP-ribosylation is also involved in counteracting heavy metal toxicity and maintaining genomic integrity, and that PARylation is implicated in chromatin remodelling but its role in sperm chromatin remains to be elucidated, we investigated the effects of chromium(VI) at 1, 10 and 100 nM on the reproductive health of Mytilus galloprovincialis. The damage to the gonads was assessed by morphological analyses and the damage indices PARP and É£H2A.X were measured. Changes in the binding of protamine-like (PL) to DNA and the possibility of poly(ADP-ribosyl)ation of PL proteins were also investigated. Gonadal chromium accumulation and morphological damage were found, especially when the mussels were exposed to the highest dose of chromium(VI). In addition, the maximum expression of gonadal É£H2A.X and PARP were obtained at 100 and 10 nM Cr(VI), respectively. Interestingly, for the first time in all exposed conditions, poly(ADP)-ribosylation was detected on PL-II, which, together with PL-III and PL-IV, are the major nuclear basic proteins of Mytilus galloprovincialis sperm chromatin. Since PL-II is involved in the final high level of sperm chromatin compaction, this post-translational modification altered the binding of the PL protein to DNA, favouring the action of micrococcal nuclease on sperm chromatin. This study provides new insights into the effects of chromium(VI) on Mytilus galloprovincialis reproductive system and proposes a molecular mechanism hypothesis describing the toxic effects of this metal on PL-DNA binding, sperm chromatin and gonads.

Serum dysregulation of serine and glycine metabolism as predictive biomarker for cognitive decline in frail elderly subjects.

Frailty is a common age-related clinical syndrome characterized by a decline in the function of multiple organ systems, increased vulnerability to stressors, and a huge socio-economic burden. Despite recent research efforts, the physiopathological mechanisms underlying frailty remain elusive and biomarkers able to predate its occurrence in the early stages are still lacking. Beyond its physical component, cognitive decline represents a critical domain of frailty associated with higher risk of adverse health outcomes. We measured by High-Performance Liquid Chromatography (HPLC) a pool of serum amino acids including L-glutamate, L-aspartate, glycine, and D-serine, as well as their precursors L-glutamine, L-asparagine, and L-serine in a cohort of elderly subjects encompassing the entire continuum from fitness to frailty. These amino acids are known to orchestrate excitatory and inhibitory neurotransmission, and in turn, to play a key role as intermediates of energy homeostasis and in liver, kidney, muscle, and immune system metabolism. To comprehensively assess frailty, we employed both the Edmonton Frail Scale (EFS), as a practical tool to capture the multidimensionality of frailty, and the frailty phenotype, as a measure of physical function. We found that D-serine and D-/Total serine ratio were independent predictors of EFS but not of physical frailty. Furthermore, higher levels of glycine, glycine/L-serine and D-/Total serine were associated with worse cognition and depressive symptoms in the frail group. These findings suggest that changes in peripheral glycine and serine enantiomers homeostasis may represent a novel biochemical correlate of frailty.

Blood D-serine levels correlate with aging and dopaminergic treatment in Parkinson's disease.

We recently described increased D- and L-serine concentrations in the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys, the post-mortem caudate-putamen of human Parkinson's disease (PD) brains and the cerebrospinal fluid (CSF) of de novo living PD patients. However, data regarding blood D- and L-serine levels in PD are scarce. Here, we investigated whether the serum profile of D- and L-serine, as well as the other glutamate N-methyl-D-aspartate ionotropic receptor (NMDAR)-related amino acids, (i) differs between PD patients and healthy controls (HC) and (ii) correlates with clinical-demographic features and levodopa equivalent daily dose (LEDD) in PD. Eighty-three consecutive PD patients and forty-one HC were enrolled. PD cohort underwent an extensive clinical characterization. Serum levels of D- and L-serine, L-glutamate, L-glutamine, L-aspartate, L-asparagine and glycine were determined using High Performance Liquid Chromatography. In age- and sex-adjusted analyses, no differences emerged in the serum levels of D-serine, L-serine and other NMDAR-related amino acids between PD and HC. However, we found that D-serine and D-/Total serine ratio positively correlated with age in PD but not in HC, and also with PD age at onset. Moreover, we found that higher LEDD correlated with lower levels of D-serine and the other excitatory amino acids. Following these results, the addition of LEDD as covariate in the analyses disclosed a selective significant increase of D-serine in PD compared to HC (Δ ≈ 38%). Overall, these findings suggest that serum D-serine and D-/Total serine may represent a valuable biochemical signature of PD.

Pathogenic germline variants in patients with endometrial cancer of diverse ancestry.

BACKGROUND: Racial disparities in outcomes exist in endometrial cancer (EC). The contribution of ancestry-based variations in germline pathogenic variants (gPVs) is unknown. METHODS: Germline assessment of ≥76 cancer predisposition genes was performed in patients with EC undergoing tumor-normal Memorial Sloan Kettering Cancer Center Integrated Mutation Profiling of Actionable Cancer Targets sequencing from January 1, 2015 through June 30, 2021. Self-reported race/ethnicity and Ashkenazi Jewish ancestry data classified patients into groups. Genetic ancestry was inferred from Memorial Sloan Kettering Cancer Center Integrated Mutation Profiling of Actionable Cancer Targets. Rates of gPV and genetic counseling were compared by ancestry. RESULTS: Among 1625 patients with EC, 216 (13%) had gPVs; 15 had >1 gPV. Rates of gPV varied by self-reported ancestry (Ashkenazi Jewish, 40/202 [20%]; Asian, 15/124 [12%]; Black/African American (AA), 12/171 [7.0%]; Hispanic, 15/124 [12%]; non-Hispanic (NH) White, 129/927 [14%]; missing, 5/77 [6.5%]; p = .009], with similar findings by genetic ancestry (p < .001). We observed a lower likelihood of gPVs in patients of Black/AA (odds ratio [OR], 0.44; 95% CI, 0.22-0.81) and African (AFR) ancestry (OR, 0.42; 95% CI, 0.18-0.85) and a higher likelihood in patients of Ashkenazi Jewish genetic ancestry (OR, 1.62; 95% CI; 1.11-2.34) compared with patients of non-Hispanic White/European ancestry, even after adjustment for age and molecular subtype. Somatic landscape influenced gPVs with lower rates of microsatellite instability-high tumors in patients of Black/AA and AFR ancestry. Among those with newly identified gPVs (n = 114), 102 (89%) were seen for genetic counseling, with lowest rates among Black/AA (75%) and AFR patients (67%). CONCLUSIONS: In those with EC, gPV and genetic counseling varied by ancestry, with lowest rates among Black/AA and AFR patients, potentially contributing to disparities in outcomes given implications for treatment and cancer prevention. PLAIN LANGUAGE SUMMARY: Black women with endometrial cancer do worse than White women, and there are many reasons for this disparity. Certain genetic changes from birth (mutations) can increase the risk of cancer, and it is unknown if rates of these changes are different between different ancestry groups. Genetic mutations in 1625 diverse women with endometrial cancer were studied and the lowest rates of mutations and genetic counseling were found in Black and African ancestry women. This could affect their treatment options as well as their families and may make disparities worse.

Clinical and molecular characteristics of early-onset vs average-onset esophagogastric cancer.

BACKGROUND: The rate of esophagogastric cancer is rising among individuals under 50 years of age. It remains unknown whether early-onset esophagogastric cancer represents a unique entity. This study investigated the clinical and molecular characteristics of early-onset and average-onset esophagogastric cancer . METHODS: We reviewed the Memorial Sloan Kettering Cancer Center gastric, esophageal, and gastroesophageal junction cancer database. Associations between baseline characteristics and tumor and germline molecular alterations were compared between those with early-onset and average-onset esophagogastric cancer using Fisher exact tests and the Benjamini-Hochberg method for multiple-hypothesis correction. RESULTS: We included 1123 patients with early-onset esophagogastric cancer (n = 219; median age = 43 years [range = 18-49 years]) and average-onset esophagogastric cancer (n = 904; median age = 67 years [range = 50-94 years]) treated between 2005 and 2018. The early-onset group had more women (39% vs 28%, P = .002). Patients with early-onset esophagogastric cancer were more likely to have a gastric primary site (64% vs 44%, P < .0001). The signet ring cell and/or diffuse type was 3 times more common in the early-onset esophagogastric cancer group (31% vs 9%, P < .0001). Early-onsite tumors were more frequently genomically stable (31% vs 18%, P = .0002) and unlikely to be microsatellite instability high (2% vs 7%, P = .003). After restricting to adenocarcinoma and signet ring cell and/or diffuse type carcinomas, we observed no difference in stage (P = .40) or overall survival from stage IV diagnosis (median = 22.7 vs 22.1 months, P = .78). CONCLUSIONS: Our study supported a preponderance of gastric primary disease sites, signet ring histology, and genomically stable molecular subtypes in early-onset esophagogastric cancer. Our findings highlight the need for further research to define the underlying pathogenesis and strategies for early detection and prevention.

Pathogenic germline variants in non-BRCA1/2 homologous recombination genes in ovarian cancer: Analysis of tumor phenotype and survival.

OBJECTIVE: To define molecular features of ovarian cancer (OC) with germline pathogenic variants (PVs) in non-BRCA homologous recombination (HR) genes and analyze survival compared to BRCA1/2 and wildtype (WT) OC. METHODS: We included patients with OC undergoing tumor-normal sequencing (MSK-IMPACT) from 07/01/2015-12/31/2020, including germline assessment of BRCA1/2 and other HR genes ATM, BARD1, BRIP1, FANCA, FANCC, NBN, PALB2, RAD50, RAD51B, RAD51C, and RAD51D. Biallelic inactivation was assessed within tumors. Progression-free (PFS) and overall survival (OS) were calculated from pathologic diagnosis using the Kaplan-Meier method with left truncation. Whole-exome sequencing (WES) was performed in a subset. RESULTS: Of 882 patients with OC, 56 (6.3%) had germline PVs in non-BRCA HR genes; 95 (11%) had BRCA1-associated OC (58 germline, 37 somatic); and 59 (6.7%) had BRCA2-associated OC (40 germline, 19 somatic). High rates of biallelic alterations were observed among germline PVs in BRIP1 (11/13), PALB2 (3/4), RAD51B (3/4), RAD51C (3/4), and RAD51D (8/10). In cases with WES (27/35), there was higher tumor mutational burden (TMB; median 2.5 [1.1-6.0] vs. 1.2 mut/Mb [0.6-2.6]) and enrichment of HR-deficient (HRD) mutational signatures in tumors associated with germline PALB2 and RAD51B/C/D compared with BRIP1 PVs (p < 0.01). Other features of HRD, including telomeric-allelic imbalance (TAI) and large-scale state transitions (LSTs), were similar. Although there was heterogeneity in PFS/OS by gene group, only BRCA1/2-associated OC had improved survival compared to WT OC (p < 0.01). CONCLUSIONS: OCs associated with germline PVs in non-BRCA HR genes represent a heterogenous group, with PALB2 and RAD51B/C/D associated with an HRD phenotype.

Neoplasia risk in patients with Lynch syndrome treated with immune checkpoint blockade.

Metastatic and localized mismatch repair-deficient (dMMR) tumors are exquisitely sensitive to immune checkpoint blockade (ICB). The ability of ICB to prevent dMMR malignant or pre-malignant neoplasia development in patients with Lynch syndrome (LS) is unknown. Of 172 cancer-affected patients with LS who had received ≥1 ICB cycles, 21 (12%) developed subsequent malignancies after ICB exposure, 91% (29/32) of which were dMMR, with median time to development of 21 months (interquartile range, 6-38). Twenty-four of 61 (39%) ICB-treated patients who subsequently underwent surveillance colonoscopy had premalignant polyps. Within matched pre-ICB and post-ICB follow-up periods, the overall rate of tumor development was unchanged; however, on subgroup analysis, a decreased incidence of post-ICB visceral tumors was observed. These data suggest that ICB treatment of LS-associated tumors does not eliminate risk of new neoplasia development, and LS-specific surveillance strategies should continue. These data have implications for immunopreventative strategies and provide insight into the immunobiology of dMMR tumors.

Germline Pathogenic Variants and Genetic Counseling by Ancestry in Patients With Epithelial Ovarian Cancer.

PURPOSE: To evaluate rates of germline pathogenic/likely pathogenic variants (PVs) and genetic counseling by ancestry in patients with epithelial ovarian cancer (EOC). METHODS: Patients with pathologically confirmed EOC who underwent clinical tumor-normal sequencing from January 1, 2015, to December 31, 2020, inclusive of germline analysis of ≥76 genes were included. Patients with newly identified PVs were referred for Clinical Genetics Service (CGS) counseling. Ancestry groups were defined using self-reported race/ethnicity and Ashkenazi Jewish (AJ) heritage. Genetic ancestry was inferred computationally using validated algorithms. Logistic regression models were built. RESULTS: Of 1,266 patients, self-reported ancestry (AJ, 17%; Asian, 10%; Black/African American, 5.4%; Hispanic, 6.2%; non-Hispanic White, 57%; other, 0.16%; unknown, 4.0%) correlated with genetic ancestry (AJ ancestry, 18%; admixed, 10%; African, 4%; East Asian [EAS], 6%; European, 56%; Native American, 0.2%; South Asian [SAS], 4%; unknown, 2%). Germline PVs were observed in 313 (25%) patients, including 195 (15%) with PVs in EOC-associated genes. Those with PVs were younger at diagnosis (59 v 62 years; P < .001) and more likely to have high-grade serous ovarian cancer (83% v 72%; P = .009). PV prevalence varied between ancestry groups (P < .001), with highest rates in the AJ (39.9%) and Asian (26.5%) groups and similar rates (>10%) across other ancestry groups. Use of genetic ancestry demonstrated similar findings and further characterized high rates of PV in EAS/SAS groups. Younger age, high-grade serous histology, and self-reported AJ or Asian ancestry were associated with PV in an EOC-associated gene. Rates of CGS counseling for newly identified PVs were high (80%) across ancestry groups. CONCLUSION: Rates of PV, particularly in EOC-associated genes, were high regardless of ancestry, with similar rates of counseling between groups, emphasizing the importance of universal genetic testing in all patients with EOC.

Unique Genomic Alterations and Microbial Profiles Identified in Patients With Gastric Cancer of African, European, and Asian Ancestry: A Novel Path for Precision Oncology.

OBJECTIVE: Here, we characterize differences in the genetic and microbial profiles of GC in patients of African (AFR), European, and Asian ancestry. BACKGROUND: Gastric cancer (GC) is a heterogeneous disease with clinicopathologic variations due to a complex interplay of environmental and biological factors, which may affect disparities in oncologic outcomes.. METHODS: We identified 1042 patients with GC with next-generation sequencing data from an institutional Integrated Mutation Profiling of Actionable Cancer Targets assay and the Cancer Genomic Atlas group. Genetic ancestry was inferred from markers captured by the Integrated Mutation Profiling of Actionable Cancer Targets and the Cancer Genomic Atlas whole exome sequencing panels. Tumor microbial profiles were inferred from sequencing data using a validated microbiome bioinformatics pipeline. Genomic alterations and microbial profiles were compared among patients with GC of different ancestries. RESULTS: We assessed 8023 genomic alterations. The most frequently altered genes were TP53 , ARID1A , KRAS , ERBB2 , and CDH1 . Patients of AFR ancestry had a significantly higher rate of CCNE1 alterations and a lower rate of KRAS alterations ( P < 0.05), and patients of East Asian ancestry had a significantly lower rate of PI3K pathway alterations ( P < 0.05) compared with other ancestries. Microbial diversity and enrichment did not differ significantly across ancestry groups ( P > 0.05). CONCLUSIONS: Distinct patterns of genomic alterations and variations in microbial profiles were identified in patients with GC of AFR, European, and Asian ancestry. Our findings of variation in the prevalence of clinically actionable tumor alterations among ancestry groups suggest that precision medicine can mitigate oncologic disparities.

Perturbation of serine enantiomers homeostasis in the striatum of MPTP-lesioned monkeys and mice reflects the extent of dopaminergic midbrain degeneration.

Loss of dopaminergic midbrain neurons perturbs l-serine and d-serine homeostasis in the post-mortem caudate putamen (CPu) of Parkinson's disease (PD) patients. However, it is unclear whether the severity of dopaminergic nigrostriatal degeneration plays a role in deregulating serine enantiomers' metabolism. Here, through high-performance liquid chromatography (HPLC), we measured the levels of these amino acids in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys and MPTP-plus-probenecid (MPTPp)-treated mice to determine whether and how dopaminergic midbrain degeneration affects the levels of serine enantiomers in various basal ganglia subregions. In addition, in the same brain regions, we measured the levels of key neuroactive amino acids modulating glutamatergic neurotransmission, including l-glutamate, glycine, l-aspartate, d-aspartate, and their precursors l-glutamine, l-asparagine. In monkeys, MPTP treatment produced severe denervation of nigrostriatal dopaminergic fibers (⁓75%) and increased the levels of serine enantiomers in the rostral putamen (rPut), but not in the subthalamic nucleus, and the lateral and medial portion of the globus pallidus. Moreover, this neurotoxin significantly reduced the protein expression of the astrocytic serine transporter ASCT1 and the glycolytic enzyme GAPDH in the rPut of monkeys. Conversely, concentrations of d-serine and l-serine, as well as ASCT1 and GAPDH expression were unaffected in the striatum of MPTPp-treated mice, which showed only mild dopaminergic degeneration (⁓30%). These findings unveil a link between the severity of dopaminergic nigrostriatal degeneration and striatal serine enantiomers concentration, ASCT1 and GAPDH expression. We hypothesize that the up-regulation of d-serine and l-serine levels occurs as a secondary response within a homeostatic loop to support the metabolic and neurotransmission demands imposed by the degeneration of dopaminergic neurons.

Prevalence and Clinical Implications of Mismatch Repair-Proficient Colorectal Cancer in Patients With Lynch Syndrome.

PURPOSE: Lynch syndrome (LS)-associated colorectal cancer (CRC) is characterized by mismatch repair-deficiency (MMR-D) and/or microsatellite instability (MSI). However, with increasing utilization of germline testing, MMR-proficient (MMR-P) and/or microsatellite stable (MSS) CRC has also been observed. We sought to characterize MMR-P/MSS CRC among patients with LS. METHODS: Patients with solid tumors with germline MMR pathogenic/likely pathogenic (P/LP) variants were identified on a prospective matched tumor-normal next-generation sequencing (NGS) protocol. CRCs were evaluated for MMR-D via immunohistochemical (IHC) staining and/or MSI via NGS. Clinical variables were correlated with MMR status using nonparametric tests. RESULTS: Among 17,617 patients with solid tumors, 1.4% (n = 242) had LS. A total of 36% (86 of 242) of patients with LS had at least one CRC that underwent NGS profiling, amounting to 99 pooled CRCs assessed. A total of 10% (10 of 99) of CRCs were MMR-P, with 100% concordance between MSS status and retained MMR protein staining. A total of 89% (8 of 9) of patients in the MMR-P group had MSH6 or PMS2 variants, compared with 30% (23 of 77) in the MMR-D group (P = .001). A total of 46% (6 of 13) of PMS2+ patients had MMR-P CRC. The median age of onset was 58 and 43 years for MMR-P and MMR-D CRC, respectively (P = .07). Despite the later median age of onset, 40% (4 of 10) of MMR-P CRCs were diagnosed <50. A total of 60% (6 of 10) of MMR-P CRCs were metastatic compared with 13% (12 of 89) of MMR-D CRCs (P = .002). A total of 33% (3 of 9) of patients with MMR-P CRC did not meet LS testing criteria. CONCLUSION: Patients with LS remained at risk for MMR-P CRC, which was more prevalent among patients with MSH6 and PMS2 variants. MMR-P CRC was later onset and more commonly metastatic compared with MMR-D CRC. Confirmation of tumor MMR/MSI status is critical for patient management and familial risk estimation.

Cerebrospinal fluid, brain, and spinal cord levels of L-aspartate signal excitatory neurotransmission abnormalities in multiple sclerosis patients and experimental autoimmune encephalomyelitis mouse model.

The neuroinflammatory process characterizing multiple sclerosis (MS) is associated with changes in excitatory synaptic transmission and altered central concentrations of the primary excitatory amino acid, L-glutamate (L-Glu). Recent findings report that cerebrospinal fluid (CSF) levels of L-Glu positively correlate with pro-inflammatory cytokines in MS patients. However, to date, there is no evidence about the relationship between the other primary excitatory amino acid, L-aspartate (L-Asp), its derivative D-enantiomer, D-aspartate, and the levels of pro-inflammatory and anti-inflammatory cytokines in the CSF of MS. In the present study, we measured by HPLC the levels of these amino acids in the cortex, hippocampus, cerebellum, and spinal cord of mice affected by experimental autoimmune encephalomyelitis (EAE). Interestingly, in support of glutamatergic neurotransmission abnormalities in neuroinflammatory conditions, we showed reduced L-Asp levels in the cortex and spinal cord of EAE mice and increased D-aspartate/total aspartate ratio within the cerebellum and spinal cord of these animals. Additionally, we found significantly decreased CSF levels of L-Asp in both relapsing-remitting (n = 157) MS (RR-MS) and secondary progressive/primary progressive (n = 22) (SP/PP-MS) patients, compared to control subjects with other neurological diseases (n = 40). Importantly, in RR-MS patients, L-Asp levels were correlated with the CSF concentrations of the inflammatory biomarkers G-CSF, IL-1ra, MIP-1ß, and Eotaxin, indicating that the central content of this excitatory amino acid, as previously reported for L-Glu, reflects a neuroinflammatory environment in MS. In keeping with this, we revealed that CSF L-Asp levels were positively correlated with those of L-Glu, highlighting the convergent variation of these two excitatory amino acids under inflammatory synaptopathy occurring in MS.

Homeostasis of serine enantiomers is disrupted in the post-mortem caudate putamen and cerebrospinal fluid of living Parkinson's disease patients.

L-serine generated in astrocytes plays a pivotal role in modulating essential neurometabolic processes, while its enantiomer, D-serine, specifically regulates NMDA receptor (NMDAR) signalling. Despite their physiological relevance in modulating cerebral activity, serine enantiomers metabolism in Parkinson's disease (PD) remains elusive. Using High-Performance Liquid Chromatography (HPLC), we measured D- and L-serine levels along with other amino acids known to modulate NMDAR function, such as L-glutamate, L-aspartate, D-aspartate, and glycine, in the post-mortem caudate putamen (CPu) and superior frontal gyrus (SFG) of PD patients. Moreover, we examined these amino acids in the cerebrospinal fluid (CSF) of de novo living PD, Alzheimer's disease (AD), and amyotrophic lateral sclerosis (ALS) patients versus subjects with other neurological disorders (OND), used as control. We found higher D-serine and L-serine levels in the CPu of PD patients but not in the SFG, a cerebral region that, in contrast to the CPu, is not innervated by nigral dopaminergic terminals. We also highlighted a significant elevation of both serine enantiomers in the CSF samples from PD but not in those of AD and ALS patients, compared with control subjects. By contrast, none or only minor changes were found in the amount of other NMDAR modulating amino acids. Our findings identify D-serine and L-serine level upregulation as a biochemical signature associated with nigrostriatal dopaminergic degeneration in PD.

The Impact of Germline Alterations in Appendiceal Adenocarcinoma.

PURPOSE: More than 10% of assessed patients with appendiceal adenocarcinoma have a pathogenic (P) or likely pathogenic (LP) germline variant, including genes implicated in heritable gastrointestinal cancer syndromes, such as Lynch syndrome. We defined the clinical and molecular impact of heritable alterations in appendiceal adenocarcinoma to evaluate the need for dedicated appendiceal screening and prevention strategies in patients with LP/P germline variants. EXPERIMENTAL DESIGN: We performed an integrated germline and somatic molecular analysis for patients with confirmed appendiceal adenocarcinoma. Patients underwent paired tumor-normal sequencing for up to 90 hereditary cancer risk genes and 505 genes for somatic mutation profiling. We defined the cooccurrence of LP/P germline variants and second-hit pathogenic somatic alterations. The associations between germline variants and patient clinicopathologic features were also evaluated. RESULTS: Twenty-five of 237 patients (10.5%) carried pathogenic or likely pathogenic germline variants in cancer susceptibility genes. Clinicopathologic characteristics and appendiceal adenocarcinoma-specific survival were similar in patients with or without germline variants. Most (92%, N = 23/25) patients with germline variants demonstrated no second-hit somatic alterations, including loss of heterozygosity. Two patients with a germline APC I1307K low-penetrance founder variant exhibited secondary somatic pathogenic alterations in APC. However, only one patient tumor exhibited APC-mediated WNT signaling dysregulation: a plausible consequence of multiple somatic APC mutations with no germline variant contribution. Four patients had germline variants in PMS2 or MSH2 associated with Lynch syndrome, yet their cancers were microsatellite-stable. CONCLUSIONS: Germline variants are likely incidental without a contributory driver role in appendiceal adenocarcinoma. Appendiceal adenocarcinoma screening in patients with germline variants is not clearly merited.

Germline drivers of gynecologic carcinosarcomas.

OBJECTIVES: To describe the prevalence of germline pathogenic variants (gPVs) in endometrial and ovarian carcinosarcomas and determine if gPVs are drivers of carcinosarcoma. METHODS: Patients with endometrial or ovarian carcinosarcomas who underwent clinical tumor-normal sequencing from 1/1/2015 to 6/1/2021 and consented to germline assessment of ≥76 cancer predisposition genes were included. In patients with gPVs, biallelic inactivation was identified through analysis of loss of heterozygosity and somatic pathogenic alterations. RESULTS: Of 216 patients identified, 167 (77%) were diagnosed with endometrial carcinosarcoma and 49 (23%) with ovarian carcinosarcoma. Overall, 33 gPVs were observed in 29 patients (13%); 20 gPVs (61%) had biallelic loss in tumors. The rate of high-penetrance gPVs overall was 7% (16 of 216); 88% of high-penetrance gPVs had biallelic loss. In the endometrial carcinosarcoma cohort, 22 gPVs were found in 19 (11%) of 167 patients; 12 gPVs (55%) had biallelic loss in tumors, including 8 (89%) of 9 in high-penetrance gPVs. Among the ovarian carcinosarcoma cohort, 11 gPVs were found in 10 (20%) of 49 patients; 8 gPVs (73%) had biallelic loss in tumors, and all evaluable high-penetrance gPVs (n = 6) had biallelic loss. All gPVs in homologous recombination (BRCA1, BRCA2, RAD51C) and Lynch syndrome (MSH2, MSH6) genes had biallelic loss in tumors (n = 15). CONCLUSIONS: gPVs in genes affecting homologous recombination- or Lynch-associated mismatch repair exhibited biallelic inactivation within tumors, suggesting likely drivers of gynecologic carcinosarcoma. Our data support germline testing for patients with gynecologic carcinosarcomas, given implications for treatment and risk-reduction in patients and at-risk family members.

D-Aspartate Depletion Perturbs Steroidogenesis and Spermatogenesis in Mice.

High levels of free D-aspartate (D-Asp) are present in vertebrate testis during post-natal development, coinciding with the onset of testosterone production, which suggests that this atypical amino acid might participate in the regulation of hormone biosynthesis. To elucidate the unknown role of D-Asp on testicular function, we investigated steroidogenesis and spermatogenesis in a one-month-old knockin mouse model with the constitutive depletion of D-Asp levels due to the targeted overexpression of D-aspartate oxidase (DDO), which catalyzes the deaminative oxidation of D-Asp to generate the corresponding α-keto acid, oxaloacetate, hydrogen peroxide, and ammonium ions. In the Ddo knockin mice, we found a dramatic reduction in testicular D-Asp levels, accompanied by a significant decrease in the serum testosterone levels and testicular 17ß-HSD, the enzyme involved in testosterone biosynthesis. Additionally, in the testes of these Ddo knockin mice, the expression of PCNA and SYCP3 proteins decreased, suggesting alterations in spermatogenesis-related processes, as well as an increase in the cytosolic cytochrome c protein levels and TUNEL-positive cell number, which indicate an increase in apoptosis. To further investigate the histological and morphometric testicular alterations in Ddo knockin mice, we analyzed the expression and localization of prolyl endopeptidase (PREP) and disheveled-associated activator of morphogenesis 1 (DAAM1), two proteins involved in cytoskeletal organization. Our results showed that the testicular levels of DAAM1 and PREP in Ddo knockin mice were different from those in wild-type animals, suggesting that the deficiency of D-Asp is associated with overall cytoskeletal disorganization. Our findings confirmed that physiological D-Asp influences testosterone biosynthesis and plays a crucial role in germ cell proliferation and differentiation, which are required for successful reproduction.

Synthesis and Degradation of Poly(ADP-ribose) in Zebrafish Brain Exposed to Aluminum.

Poly(ADPribosyl)ation is a post-translational protein modification, catalyzed by poly(ADP-ribose) polymerase (PARPs) enzymes, responsible for ADP-ribose polymer synthesis (PAR) from NAD+. PAR turnover is assured by poly(ADPR) glycohydrolase (PARGs) enzymes. In our previous study, the altered histology of zebrafish brain tissue, resulting in demyelination and neurodegeneration also with poly(ADPribosyl)ation hyperactivation, was demonstrated after aluminum (Al) exposure for 10 and 15 days. On the basis of this evidence, the aim of the present research was to study the synthesis and degradation of poly(ADP-ribose) in the brain of adult zebrafish exposed to 11 mg/L of Al for 10, 15, and 20 days. For this reason, PARP and PARG expression analyses were carried out, and ADPR polymers were synthesized and digested. The data showed the presence of different PARP isoforms, among which a human PARP1 counterpart was also expressed. Moreover, the highest PARP and PARG activity levels, responsible for the PAR production and its degradation, respectively, were measured after 10 and 15 days of exposure. We suppose that PARP activation is related to DNA damage induced by Al, while PARG activation is needed to avoid PAR accumulation, which is known to inhibit PARP and promote parthanatos. On the contrary, PARP activity decrease at longer exposure times suggests that neuronal cells could adopt the stratagem of reducing polymer synthesis to avoid energy expenditure and allow cell survival.

Antioxidant Characterization of Six Tomato Cultivars and Derived Products Destined for Human Consumption.

The consumption of fresh tomatoes and processed tomato products is widespread in the Mediterranean diet. This fruit is a valuable source of antioxidants and plays an important role in preventing oxidative stress. This study aimed to investigate the content of antioxidants and measure the total antioxidant capacity (ABTS and DPPH assays) in the peel, pulp, and seed fractions of six tomato cultivars. Finally, some bioactive compounds and total antioxidant activity were also determined in homemade tomato purees, since such homemade production is commonplace in Southern Italy. The level of antioxidants and total antioxidant capacity in each fraction were also calculated based on their actual fresh weight in the whole tomato. The overall results indicated that the peel and seeds of all analysed tomato cultivars contribute significantly to the antioxidant charge of the fruits. Consequently, consuming tomatoes without peel and seeds results in a substantial loss of compounds beneficial for human health. Our results also showed that phenolic and lycopene content, as well as antioxidant activities in all purees are higher than in fresh tomatoes. Based on this evidence, producing homemade tomato puree is a good practice, and its consumption helps prevent oxidative stress damage.

A Molecular Mechanism to Explain the Nickel-Induced Changes in Protamine-like Proteins and Their DNA Binding Affecting Sperm Chromatin in Mytilus galloprovincialis: An In Vitro Study.

Nickel is associated with reproductive toxicity, but little is known about the molecular mechanisms of nickel-induced effects on sperm chromatin and protamine-like proteins (PLs). In the present work, we analyzed PLs from Mytilus galloprovincialis by urea-acetic acid polyacrylamide gel electrophoresis (AU-PAGE) and SDS-PAGE and assessed their binding to DNA by Electrophoretic Mobility Shift Assay (EMSA) after exposing mussels to 5, 15, and 35 µM NiCl2 for 24 h. In addition, a time course of digestion with MNase and release of PLs from sperm nuclei by the NaCl gradient was performed. For all exposure doses, in AU-PAGE, there was an additional migrating band between PL-III and PL-IV, corresponding to a fraction of PLs in the form of peptides detected by SDS-PAGE. Alterations in DNA binding of PLs were observed by EMSA after exposure to 5 and 15 µM NiCl2, while, at all NiCl2 doses, increased accessibility of MNase to sperm chromatin was found. The latter was particularly relevant at 15 µM NiCl2, a dose at which increased release of PLII and PLIII from sperm nuclei and the highest value of nickel accumulated in the gonads were also found. Finally, at all exposure doses, there was also an increase in PARP expression, but especially at 5 µM NiCl2. A possible molecular mechanism for the toxic reproductive effects of nickel in Mytilus galloprovincialis is discussed.

Comprehensive analysis of germline drivers in endometrial cancer.

BACKGROUND: We sought to determine the prevalence of germline pathogenic variants (gPVs) in unselected patients with endometrial cancer (EC), define biallelic gPVs within tumors, and describe their associations with clinicopathologic features. METHODS: Germline assessment of at least 76 cancer predisposition genes was performed in patients with EC undergoing clinical tumor-normal Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) sequencing from January 1, 2015, to June 30, 2021. In patients with gPVs, biallelic alterations in ECs were identified through analysis of loss of heterozygosity and somatic PVs. Clinicopathologic variables were compared using nonparametric tests. RESULTS: Of 1625 patients with EC, 216 (13%) had gPVs, and 15 patients had 2 gPVs. There were 231 gPVs in 35 genes (75 [32%] high penetrance; 39 [17%] moderate penetrance; and 117 [51%] low, recessive, or uncertain penetrance). Compared with those without gPVs, patients with gPVs were younger (P = .002), more often White (P = .009), and less obese (P = .025) and had differences in distribution of tumor histology (P = .017) and molecular subtype (P < .001). Among 231 gPVs, 74 (32%) exhibited biallelic inactivation within tumors. For high-penetrance gPVs, 63% (47 of 75) of ECs had biallelic alterations, primarily affecting mismatch repair (MMR) and homologous recombination related genes, including BRCA1,BRCA2, RAD51D, and PALB2. Biallelic inactivation varied across molecular subtypes with highest rates in microsatellite instability-high (MSI-H) or copy-number (CN)-high subtypes (3 of 12 [25%] POLE, 30 of 77 [39%] MSI-H, 27 of 60 [45%] CN-high, 9 of 57 [16%] CN-low; P < .001). CONCLUSIONS: Of unselected patients with EC, 13% had gPVs, with 63% of gPVs in high-penetrance genes (MMR and homologous recombination) exhibiting biallelic inactivation, potentially driving cancer development. This supports germline assessment in EC given implications for treatment and cancer prevention.