PCB126 impairs human sperm functions by affecting post-translational modifications and mitochondrial functions.

Over the past few decades, there has been a consistent decline in semen quality across the globe, with environmental pollution being identified as the primary cause. Among the various contaminants present in the environment, persistent organic pollutants (POPs) have garnered significant attention due to their high toxicity, slow degradation, bio-accumulation, and long-range migration. PCBs, which include 210 congeners, are a crucial type of POPs that are known to have harmful effects on the environment and human health. Among the various PCB congeners, 3,3',4,4',5-pentachlorobiphenyl (PCB126) is a typical environmental endocrine-disrupting chemical that is widely distributed and has been associated with several health hazards. However, the impact and mechanism of PCB126 on human sperm function has not been fully elucidated. We aimed to investigate the effects of different concentrations of PCB126 (0.01, 0.1, 1, 10 µg/mL) on sperm motility, viability, hyperactivation, and acrosome reaction after incubation for different periods (1 and 2 h), delving deeper into the molecular mechanism of human sperm dysfunction caused by PCB126. First, we investigated the link between PCB126 treatment and the occurrence of protein modifications that are critical to sperm function regulation, such as tyrosine phosphorylation and lysine glutarylation. Second, we examined the potential impact of PCB126 on different parameters related to mitochondrial function, including reactive oxygen species, malondialdehyde levels, mitochondrial membrane potential, mitochondria respiration and adenosine triphosphate generation. Our findings indicate that exposure to environmental pollutants such as PCB126 in vitro may have a negative impact on human sperm functions by interfering with post-translational modifications and mitochondrial functions.

Efficacy of platinum-based and non-platinum-based drugs on triple-negative breast cancer: meta-analysis.

BACKGROUND: Triple-negative breast cancer (TNBC), the subtype of breast cancer with the highest mortality rate, shows clinical characteristics of high heterogeneity, aggressiveness, easy recurrence, and poor prognosis, which is due to lack of expression of estrogen, progesterone receptor and human epidermal growth factor receptor 2. Currently, neoadjuvant chemotherapy (NAT) is still the major clinical treatment for triple-negative breast cancer. Chemotherapy drugs can be divided into platinum and non-platinum according to the presence of metal platinum ions in the structure. However, which kind is more suitable for treating TNBC remains to be determined. METHODS: The relevant randomized clinical trials (RCTs) that explore the effectiveness of chemotherapy regimens containing platinum-based drugs (PB) or platinum-free drugs (PF) in treating TNBC patients were retrieved through PubMed, EMBASE, Cochrane Library, CNKI, and other literature platforms, above research findings, were included in the meta-analysis. The incidence of overall remission rate (ORR), pathological complete remission rate (pCR), overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and adverse events (AE) were compared between the two groups. RESULTS: In this study, 12 clinical trials with a total of 4580 patients were included in the analysis. First, the ORR in 4 RCTs was, PB vs PF = 52% vs 48% (RR = 1.05, 95% CI: 0.91-1.21, P = 0.48); the pCR in 5 RCTs was, PB vs PF = 48% vs 41% (RR = 1.38, 95% CI: 0.88-2.16, P = 0.17). CI: 0.88-2.16, P = 0.17; the other 2 RCTs reported significantly higher DFS and OS rates in the PB group compared with the PF group, with the combined risk ratio for DFS in the PB group RR = 0.22 (95% CI:0.06-0.82, P = 0.015); the combined risk ratio for DFS in the PF group RR = 0.15 (95% CI. 0.04-0.61, P = 0.008); OS rate: PB vs PF = 0.046 vs 0.003; secondly, 2 RCTs showed that for patients with BRCA-mutated TNBC, the pCR rate in the PB and PF groups was 18% vs 26%, 95% CI: 2.4-4.2 vs 4.1-5.1; meanwhile, the median subject in the PB group The median PFS was 3.1 months (95% CI: 2.4-4.2) in the PB group and 4.4 months (95% CI: 4.1-5.1) in the PC group; finally, the results of the clinical adverse effects analysis showed that platinum-containing chemotherapy regimens significantly increased the incidence of adverse effects such as thrombocytopenia and diarrhea compared with non-platinum regimens, while the incidence of adverse effects such as vomiting, nausea, and neutropenia was reduced. The incidence of adverse reactions was reduced. CONCLUSION: Compared with non-platinum drugs, platinum drugs significantly improved clinical treatment effective indexes, such as PCR, ORR, PFS, DFS, and OS rate in the treatment of TNBC patients without BRCA mutant may cause more serious hematological adverse reactions. Accordingly, platinum-based chemotherapy should be provided for TNBC patients according to the patient's special details.