RACGAP1 promotes lung cancer cell proliferation through the PI3K/AKT signaling pathway.

We aimed to investigate the expression and clinic significance of Rac GTPase Activating Protein 1 (RACGAP1) in human lung adenocarcinoma (LUAD). Online database analysis revealed a significant increase in RACGAP1 mRNA expression among 26 types of tumor tissues, including LUAD tissues. Online database and tissue microarray analyses indicated that RACGAP1 expression was significantly upregulated in LUAD tissues. Genetic variation analysis identified four different genetic variations of RACGAPs in LUAD. Moreover, online database analysis showed that RACGAP1 upregulation was correlated with shorter survival in patients with LUAD. After silencing RACGAP1 expression in A549 cells using siRNA and assessing its protein levels via Western blotting, we found that RACGAP1 knockdown inhibited cell growth and induced apoptosis determined using the Cell Counting Kit-8 assay, colony formation assay, and flow cytometry. Mechanistically, western blot analysis indicated that Bax expression increased, whereas Bcl-2 expression decreased. Moreover, RACGAP1 knockdown attenuated PI3K/AKT pathway activation in lung cancer cells. Taken together, our findings showed that RACGAP1 was overexpressed in LUAD tissues and played an important role in lung cancer by increasing cell growth through the PI3K/AKT signaling pathway. This study suggests recommends evaluating RACGAP1 in clinical settings as a novel biomarker and potential therapeutic target for lung cancer.

Dynamic Analysis of the Impact of Micropapillary Component on Different Recurrence Patterns of Pathological Stage IA3 Lung Adenocarcinoma: A Multicenter, Retrospective Study.

BACKGROUND: This study aimed to evaluate the dynamic impact of the micropapillary (MIP) component on local recurrence (LR), distant metastasis (DM), and multiple recurrence (MR) of pathological stage IA3 lung adenocarcinoma. METHODS: Between July 2012 and July 2020, a total of 351 patients at two medical institutions were enrolled in this study. Cumulative incidence of curves, dynamic risk curves, and time-dependent multivariate analysis was performed to evaluate the effect of the MIP component on patients. RESULTS: The 5-year cumulative incidence of total recurrence with or without an MIP component was 34.2% and 12.3%, respectively (p = 0.001). In three recurrence patterns, our findings revealed that the 5-year cumulative incidence of LR (p = 0.048) and DM (p = 0.005) was higher in the 'MIP-present' group than in the 'MIP-absent' group. In the dynamic recurrence curve, the risk of the three recurrence patterns was different and varied over time between the two groups, especially in DM. Moreover, the dynamic cumulative event curve showed that after 1, 2, and 3 years of survival, the cumulative incidence of DM in the group with MIP continued to be higher than that in the group without MIP (all p < 0.05). Time-dependent Cox regression analysis indicated that the MIP component continued to be an independent risk factor for the cumulative incidence of DM in patients with 3-year survival. CONCLUSIONS: Of the three recurrence patterns, the MIP component mainly aggravated the risk of DM in patients with pathological stage IA3 lung adenocarcinoma, which persisted for 3 years.

Effects of a ground-glass opacity component on the recurrence and survival of pathological stage IA3 lung adenocarcinoma: a multi-institutional retrospective study.

Background: This study aimed to evaluate the effect of the presence of a radiographically manifested ground-glass opacity (GGO) component on the prognosis of patients with pathological stage IA3 lung adenocarcinoma. Methods: Patients diagnosed with pathological stage IA3 lung adenocarcinoma who underwent radical surgery at two medical institutions in China between July 2012 and July 2020 were enrolled. The cumulative incidence of recurrence (CIR) and cumulative incidence of death (CID) in patients with and without a GGO component were compared. Risk curves for the recurrence and tumor-related death overtime were analyzed between the two groups according to life table. In order to validate the prognostic value of GGO components, the recurrence-free survival (RFS) and cancer-specific survival (CSS) were estimated. Decision curve analysis (DCA) was performed to evaluate the clinical benefit rate of different models. Results: Among the 352 included patients, the presence of a GGO component was radiographically shown in 166 (47.2%) patients, while 186 (52.8%) displayed solid nodules. Patients exhibiting the absence of a GGO component had higher incidences of total recurrence (17.2% vs. 3.0%, P<0.001), local-regional recurrence (LRR) (5.4% vs. 0.6%, P=0.010), distant metastasis (DM) (8.1% vs. 1.8%, P=0.008), and multiple recurrences (4.3% vs. 0.6%, P=0.028) than the presence-GGO component group. The 5-year CIR and CID were 7.5% and 7.4% in the presence-GGO component group, and 24.5% and 17.0% in the absence-GGO component group, respectively, with statistically significant differences between the two groups (P<0.05). The risk of recurrence in patients with the presence of GGO components showed a single peak at 3 years postoperatively, while patients with the absence of GGO components showed a double peak at 1 and 5 years after surgery, respectively. However, the risk of tumor-related death peaked in both groups at 3 and 6 years postoperatively. Multivariate Cox analysis showed that the presence of a GGO component was a favorable independent risk factor for pathological stage IA3 lung adenocarcinoma patients (P<0.05). Conclusions: Pathological stage IA3 lung adenocarcinoma with or without GGO components are two types of tumors with different invasive abilities. In clinical practice, we should develop different treatment and follow-up strategies.

A Multi-institutional Analysis of the Combined Effect of Micropapillary Component and Consolidation-to-Tumor Ratio >0.5 on the Prognosis of Pathological, Stage IA3, Lung Adenocarcinoma.

INTRODUCTION: The study investigated the synergistic effect of the micropapillary (MIP) component and consolidation-to-tumor ratio (CTR) on the recurrence and survival of patients with pathologic stage IA3 lung adenocarcinoma. METHODS: We enrolled 419 patients confirmed pathological stage IA3 adenocarcinoma from four institutions. Kaplan-Meier analysis was performed to examine the value of the MIP component and CTR on relapse-free survival (RFS) and overall survival (OS). The cumulative recurrence between different stages was analyzed by using cumulative event curves. RESULTS: RFS (P < 0.0001) and OS (P = 0.008) in the presence of the MIP group were significantly lower than those in the absence of the MIP group, and CTR > 5 only reduced RFS (P = 0.0004), but not OS (P = 0.063), in the patients. In addition, the prognosis of patients with both the MIP component and CTR > 5 was worse than that of those without the MIP component or CTR ≤ 5. Therefore, we established new subtypes of the stage IA3: IA3a, IA3b, and IA3c. RFS and OS for IA3c staging were significantly lower than those for IA3a and IA3b. For IA3c, the cumulative incidence of local recurrence (P < 0.001) and that of distant metastasis (P = 0.004) were significantly higher than those for IA3a and IA3b. CONCLUSIONS: The MIP component combined with CTR > 0.5 can effectively predict the prognosis of patients with pathological stage IA3 lung adenocarcinoma and may offer more detailed recurrence and survival information according to the established subtype stage of IA3.

Clinical Value of Pleural Effusion and Serum MMP-3 and CYFRA21-1 Combined with ADA in Differential Diagnosis of Pleural Exudative Effusion.

Objective: The aim of the study is to investigate the clinical value of matrix metalloproteinases-3 (MMP-3) and cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) combined with adenosine deaminase (ADA) in pleural effusion and serum in benign and malignant pleural exudative effusion (PEE). Methods: A total of 119 adult patients with PEE admitted in our hospital from May 2018 to October 2021 were selected. According to the patient's condition, the patients were divided into the benign group (n = 75) and the malignant group (n = 44). The levels of MMP-3, CYFRA21-1, and ADA in pleural effusion and serum were detected. The receiver operating characteristic (ROC) curve was used to analyze the individual and combined predictive value of MMP-3, CYFRA21-1, and ADA levels. Results: In the malignant group, the pleural effusion and serum MMP-3 and CYFRA21-1 levels were higher than those in the benign group and the ADA levels were lower than those in the benign group (P < 0.05). In the malignant group, the positive detection rate of pleural effusion and serum MMP-3 and CYFRA21-1 was higher than that in the benign group and the positive detection rate of pleural effusion and serum ADA were lower than that in the benign group (P < 0.05). The AUC of pleural effusion MMP-3, serum MMP-3 and the combination of them in the diagnosis of PEE were 0.764, 0.722 and 0.810, respectively. The AUC of pleural effusion CYFRA21-1 and serum CYFRA21-1 and combination of them in the diagnosis of PEE were 0.776, 0.748 and 0.822, respectively. The AUC of pleural effusion ADA, serum ADA and their combination in differential diagnosis of PEE were 0.762, 0.737 and 0.836, respectively. The AUC of pleural effusion and serum of MMP-3 and CYFRA21-1 combined with ADA for differential diagnosis of PEE was 0.923. Conclusions: The diagnostic efficacy of MMP-3 combined with CYFRA21-1 and ADA in pleural effusion and serum for benign and malignant PEE are better than single index, which has certain clinical values for the selection of early intervention scheme for PEE patients.