The impact of EGFR T790M mutation status following the development of Osimertinib resistance on the efficacy of Osimertinib in non-small cell lung cancer: A meta-analysis.

BACKGROUND: Previous studies have suggested that loss of the EGFR T790M gene mutation may contribute to the development of resistance to Osimertinib in non-small cell lung cancer (NSCLC). AIMS: This study aims to assess the relationship between the clinical effectiveness of Osimertinib in NSCLC patients and the T790M mutation status following resistance to Osimertinib and examine differences between plasma and tissue tests and between Asian and non-Asian groups. METHODS: The PubMed, Web of Science, Cochrane, and EMBASE databases were comprehensively searched for studies on the association between T790M mutation status and the efficacy of Osimertinib between January 2014 and November 2023. Meta-analysis was carried out using Review Manager 5.4 software. RESULTS: After evaluating 2727 articles, a total of 14 studies were included in the final analysis. Positive correlations between EGFR T790M mutation status after Osimertinib resistance and longer PFS (HR: 0.44, 95% CI: 0.30-0.66), longer OS (HR: 0.3, 95% CI: 0.10-0.86), longer TTD (HR: 0.69, 95% CI: 0.45-1.07), and improved clinical outcomes including PFS and TTD subgroups (HR: 0.58, 95% CI: 0.47-0.73) were observed. Subgroup analysis revealed that, compared with the blood tests, the results of the T790M mutation tests by the tissue are more significant (HR: 0.24, 95% CI: 0.11-0.52 for tissue tests; HR: 0.47, 95% CI: 0.22-1.00 for plasma tests), and the PFS of Osimertinib were similar for Asian and non-Asian patients (HR: 0.46, 95% CI: 0.31-0.68 for Asians; HR: 0.12, 95% CI: 0.01-1.27 for non-Asians). CONCLUSIONS: Persistence of the T790M gene mutation after the development of Osimertinib resistance is associated with higher therapeutic benefits of Osimertinib in NSCLC patients. The results of tissue detection are more significant than those of plasma detection.

Comparison of osimertinib plus bevacizumab against osimertinib alone in NSCLC harboring EGFR mutations: a systematic review and meta-analysis.

Background: Frequent failures observed in some trials comparing the efficacy and safety of osimertinib plus bevacizumab to osimertinib monotherapy in advanced non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) alterations have brought questions. Objectives: To evaluate the efficacy and safety of these two treatment regimens in advanced NSCLC patients harboring EGFR mutations. Design: This study is a systematic review and meta-analysis. Data sources and methods: PubMed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, and VIP databases were extensively searched for relevant randomized controlled trials (RCTs) on 14 May 2023. Two researchers independently screened the literature, assessed quality, and extracted data. The primary outcomes were progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). The secondary outcomes were adverse events (AEs) and PFS stratified by patients' characteristics. STATA 17.0 software (StataCorp LLC, USA) was adopted for meta-analysis. Results: A total of four RCTs involving 390 patients were included. Overall, the risk of bias across the studies was moderate to low. Pooled results showed that compared to osimertinib alone, the addition of bevacizumab to osimertinib failed to show prolongation of PFS [hazard ratio (HR) = 1.00, 95% confidence interval (CI): 0.78-1.27], OS (HR = 1.01, 95% CI: 0.73-1.41), or improvement of the ORR (risk ratio = 1.12, 95% CI: 0.90-1.38), while an increased incidence of some AEs was observed, such as nausea, oral mucositis, hypertension, and proteinuria. Notably, combination treatment did significantly prolong the PFS in the subset of smokers (HR = 0.64, 95% CI: 0.44-0.94). A mild trend toward PFS benefit under the combined regimen was also noted in patients with brain metastases and first-line treatment, though not reaching statistical significance. Conclusion: Based on the available evidence, the addition of bevacizumab to osimertinib could not provide additional survival benefits with higher but manageable toxicity for EGFR-mutant NSCLC patients. Osimertinib monotherapy remains the prioritized treatment. Further investigation is warranted.

Nephrotoxicity induced by cisplatin is primarily due to the activation of the 5-hydroxytryptamine degradation system in proximal renal tubules.

As a widely used anticancer drug in the clinic, cisplatin has obvious side effects, especially nephrotoxicity. Previous studies have suggested that the accumulation of intracellular reactive oxygen species (ROS) is a hallmark of cisplatin-induced acute kidney injury. This study aimed to investigate the relationship between ROS accumulation induced by cisplatin and 5-HT degradation. In vivo, by HE and TUNEL staining, we found that cisplatin-induced renal lesions and apoptotic regions, which were located in proximal tubular epithelial cells, were also the regions in which tryptophan hydroxylase 1 (Tph1), aromatic l-amino acid decarboxylase (AADC), 5-HT2A receptor (5-HT2AR) and monoamine oxidase A (MAO-A) were overexpressed, as determined by immunohistochemistry. Notably, the 5-HT2AR antagonist sarpogrelate hydrochloride (SH) and the AADC inhibitor carbidopa (CDP) significantly attenuated cisplatin-induced increases in serum creatinine and blood urea nitrogen levels, renal ROS levels, oxidative stress (SOD activity and MDA), proinflammatory cytokine levels (NF-κB, TNF-α and IL-1ß), proapoptotic factor levels (Bax, Bcl-2, C-caspase 3 and C-caspase 9) and the phosphorylation of p38 and STAT3, as well as renal lesions and apoptosis. The combination of SH and CDP could almost abolish the effects of cisplatin challenge. In vitro, the effects of cisplatin challenge and the inhibitory effects of SH and CDP were also observed in HK-2 cells. Additionally, similar to the combination of SH and CDP, the MAO-A inhibitor clorgyline could also abolish the effects of cisplatin challenge. More importantly, by western blotting, we detected that the upregulation of Tph1, AADC and MAO-A expression induced by cisplatin both in vivo and in vitro could be obviously suppressed by SH to decrease 5-HT synthesis and mitochondrial 5-HT degradation. Altogether, these findings suggested that cisplatin-induced nephrotoxicity is due to the activation of the 5-HT degradation system in proximal tubular epithelial cells, including 5-HT2AR and 5-HT synthesis and degradation. 5-HT2AR plays a role by mediating the expression of MAO-A and the 5-HT synthases Tph1 and AADC.