Objective To explore whether there is a causal relationship between intestinal flora and esophageal cancer. Methods Summary statistics of intestinal flora and esophageal cancer were obtained from the Genome-wide Association Studies (GWAS) database. Five methods, including inverse variance weighted (IVW), weighted median estimation, Mendelian randomization (MR)-Egger regression, single mode, and weighted mode, were used for analysis, with IVW as the main analysis method. Sensitivity analysis was used to evaluate the reliability of MR results. Results In the IVW method, Oxalobacteraceae [OR=1.001, 95%CI (1.000, 1.002), P=0.023], Faecalibacterium [OR=1.001, 95%CI (1.000, 1.002), P=0.028], Senegalimassilia [OR=1.002, 95%CI (1.000, 1.003), P=0.006] and Veillonella [OR=1.001, 95%CI (1.000, 1.002), P=0.018] were positively correlated with esophageal cancer, while Burkholderiales [OR=0.999, 95%CI (0.998, 1.000), P=0.002], Eubacterium oxidoreducens [OR=0.998, 95%CI (0.997, 0.999), P=0.038], Romboutsia [OR=0.999, 95%CI (0.998, 1.000), P=0.048] and Turicibacter [OR=0.998, 95%CI (0.997, 0.999), P=0.013] were negatively correlated with esophageal cancer. Sensitivity analysis showed no evidence of heterogeneity, horizontal pleiotropy and reverse causality. Conclusion Oxalobacteraceae, Faecalibacterium, Senegalimassilia and Veillonella increase the risk of esophageal cancer, while Burkholderiales, Eubacterium oxidoreducens, Romboutsia and Turicibacter decrease the risk of esophageal cancer. Further studies are needed to explore how these bacteria affect the progression of esophageal cancer.

Objective To analyze the relationship between neuroticism and gastroesophageal reflux disease (GERD) using the Mendelian randomization (MR) method. Methods Exposure and outcome data were downloaded from the Integrative Epidemiology Unit (IEU) database in August 2023, including summary statistics from genome-wide association studies (GWAS) for neuroticism (n=374 323) and GERD (n=602 604). MR was conducted using the weighted median method, MR-Egger method, inverse variance weighted method, weighted mode method, and simple mode method. The causal relationship between the two was assessed using odds ratio (OR), and sensitivity analyses were performed to ensure the accuracy of the results. Results Neuroticism was associated with an increased risk of GERD [OR=1.229, 95%CI (1.186, 1.274), P<0.001]. Similarly, GERD was associated with an increased risk of neuroticism [OR=1.786, 95%CI (1.623, 1.965), P<0.001]. Conclusion There is a bidirectional causal relationship between neuroticism and gastroesophageal reflux disease.

Objective To identify causal effects and potential mechanisms of oxidative stress (OS)-related genes in lung cancer. Methods OS-related genes were extracted from the GeneCards database. Integration analysis of genome-wide association study (GWAS) data for lung cancer with gene expression and DNA methylation quantitative trait locus (QTL), including eQTL and mQTL in blood was performed using the summary data-based Mendelian randomization (SMR) approach to determine the causal relationship between OS-related genes and lung cancer risk. Colocalization analysis of OS-related gene QTL and lung cancer risk locus was performed to gain insight into the potential regulatory mechanisms of lung cancer risk. Results A total of 1 188 OS-related genes were obtained from the GeneCards database. A potential causal relationship between OS-related genes and lung cancer was identified by SMR analysis. AGER expression level [OR=1.944, 95%CI (1.431, 2.640), P<0.001], and ATF6B expression level [OR=1.508, 95%CI (1.287, 1.767), P<0.001] were associated with lung cancer risk. Meanwhile, ATF6B methylation level was also associated with lung cancer risk. Conclusion OS-related genes are associated with lung cancer, which may be a potential target of anti-cancer drugs.

Distant cutaneous metastasis of primary lung squamous cell carcinoma is an exceedingly rare event,with scalp metastasis as the initial clinical presentation even rarer.Scalp skin metastases are prone to be misdiagnosed as other scalp disorders,yet their appearance signifies the deterioration and poor prognosis of lung cancer.This case report documents a female patient presenting initially with scalp folliculitis in dermatology,who was subsequently diagnosed with malignant lung tumor through radiological imaging and referred to Department of Thoracic Surgery.Pathological examination of the excised lesion from the scalp revealed distant metastasis of lung cancer.A review of similar cases reported in literature was conducted.This article aims to enhance understanding and awareness of skin metastasis in lung cancer,to emphasize the importance of this condition,and to improve early recognition and precise diagnosis.It is crucial to prevent clinical misdiagnosis and ensure ap-propriate treatment,finally leading to improve the prognosis of the patients.