Efficacy of afatinib in a patient with rare EGFR (G724S/R776H) mutations and amplification in lung adenocarcinoma: A case report.

BACKGROUND: The most common EGFR mutations are in-frame deletions in exon 19 and point mutations in exon 21. Cases with classical EGFR mutations show a good response to EGFR tyrosine kinase inhibitors (TKIs), the standard first-line treatment. With the development of next generation sequencing, some uncommon genomic mutations have been detected. However, the effect of TKIs on such uncommon EGFR mutations remains unclear. CASE SUMMARY: Here, we report a case of rare EGFR co-mutation in non-small cell lung cancer and the efficacy of afatinib on this EGFR co-mutation. A 64-year-old woman was diagnosed with thoracolumbar and bilateral local rib bone metastases, bilateral pulmonary nodules, and pericardial and left pleural effusion. The pathological diagnosis was lung adenocarcinoma. To seek potential therapeutic regimens, rare co-mutation comprising rare EGFR G724S/R776H mutations and amplification were identified. The patient experienced a significant clinical response with a progression-free survival of 17 mo. CONCLUSION: A case of non-small cell lung cancer with rare EGFR G724S/R776H mutations and EGFR amplification responds well to TKI treatment.

MicroRNA-related single-nucleotide polymorphism of XPO5 is strongly correlated with the prognosis and chemotherapy response in advanced non-small-cell lung cancer patients.

This study was performed to investigate if the microRNA-related single-nucleotide polymorphisms (miR-SNPs) of XPO5 gene predicted the prognosis and pathological features of advanced non-small-cell lung cancer patients receiving chemotherapy. A total of 131 advanced non-small-cell lung cancer (NSCLC) patients were recruited. MicroRNA (miRNA) binding site prediction software was adopted for the prediction and screening of SNPs in XPO5 and miRNA binding regions. Polymerase chain reaction (PCR) amplification was further performed. Time-dependent survival-free curves were constructed using the Kaplan-Meier technique. Univariate and the multivariate survival analyses were conducted for confirmation of prognostic factor for advanced NSCLC patients receiving chemotherapy. There were no significant differences of SNP distribution frequencies between groups, without statistical significance (P > 0.05). Included clinical pathological features and chemotherapy regimens showed no apparent statistical significance in influencing the curative effect of chemotherapy in advanced NSCLC patients (all P > 0.05). While the objective response rate (ORR) in patients who carried AA and AC genotype was 35.48 and 51.22 %, respectively, with statistically significant difference (P < 0.05). Univariate survival analysis indicated that patients who carried AA genotype showed a significantly lower 5-year survival rate to those who carried AC genotype (P < 0.05). And, considering pathological features, statistical significance was found in patients with different pathological types, lymph node metastasis, differentiation degree, T staging, and pathological staging (all P < 0.05). Multivariate analysis results indicated that the SNP sites of rs11077 might be an independent prognostic factor of advanced NSCLC patients receiving chemotherapy (risk ratio [RR] = 0.346; 95 % confidence interval [95 % CI] = 0.174-0.685, P = 0.002). Other clinical features were all considered to have no apparent effect in influencing the prognostic outcomes of advanced NSCLC patients receiving chemotherapy except lymph node metastasis (P < 0.05). miR-SNP rs11077 of XPO5 may be independently connected with the prognosis and chemotherapy response of advanced NSCLC patients, and patients with AC genotype have relatively improved prognostic outcomes and better curative effect of chemotherapy than those with AA allele of XPO5. Further, lymph node metastasis may be also involved in influencing the prognosis of advanced NSCLC patients.

Pyrroloquinoline quinone protects mouse brain endothelial cells from high glucose-induced damage in vitro.

AIM: To investigate the effects of pyrroloquinoline quinone (PQQ), an oxidoreductase cofactor, on high glucose-induced mouse endothelial cell damage in vitro. METHODS: Mouse brain microvascular endothelial bEND.3 cells were exposed to different glucose concentrations (5.56, 25 and 40 mmol/L) for 24 or 48 h. The cell viability was examined using MTT assay. Flow cytometry was used to analyze the apoptosis and ROS levels in the cells. MitoTracker Green staining was used to examine the mitochondria numbers in the cells. Western blot analysis was used to analyze the expression of HIF-1α and the proteins in JNK pathway. RESULTS: Treatment of bEND.3 cells with high glucose significantly decreased the cell viability, while addition of PQQ (1 and 10 µmol/L) reversed the high glucose-induced cell damage in a concentration-dependent manner. Furthermore, PQQ (100 µmol/L) significantly suppressed the high glucose-induced apoptosis and ROS production in the cells. PQQ significantly reversed the high glucose-induced reduction in both the mitochondrial membrane potential and mitochondria number in the cells. The high glucose treatment significantly increased the expression of HIF-1α and JNK phosphorylation in the cells, and addition of PQQ led to a further increase of HIF-1α level and a decrease of JNK phosphorylation. Addition of JNK inhibitor SP600125 (10 µmol/L) also significantly suppressed high glucose-induced apoptosis and JNK phosphorylation in bEND.3 cells. CONCLUSION: PQQ protects mouse brain endothelial cells from high glucose damage in vitro by suppressing intracellular ROS and apoptosis via inhibiting JNK signaling pathway.

Application of RUNX3 gene promoter methylation in the diagnosis of non-small cell lung cancer.

The purpose of this study was to detect the methylation of the RUNX3 gene promoter in non-small cell lung cancer (NSCLC) tissue and to explore the association of this methylation with clinical features of NSCLC. In 58 samples of NSCLC tissue and normal adjacent tissue, methylation of the RUNX3 gene promoter was measured by methylation-specific polymerase chain reaction. Correlation with clinicopathological characteristics was assessed. The results demonstrated that RUNX3 gene promoter methylation was present in 26/58 (44.8%) of NSCLC tissue samples and 10/58 (17.2%) of normal tissue samples, and that the difference was statistically significant between the two groups (χ(2)=10.311, p=0.001). Significantly, methylation of the RUNX3 gene promoter correlated with clinical stage, lymph node metastasis and the degree of differentiation (p<0.05) but not with age, gender, smoking history and pathological type (p>0.05). In conclusion, methylation of the RUNX3 gene promoter had a high relevance ratio in NSCLC tissue and correlated with clinical stage, lymph node metastasis and degree of differentiation; thus, this association may have clinical significance in NSCLC.

PEBP4 gene expression and its significance in invasion and metastasis of non-small cell lung cancer.

The goal of this study was to investigate the function of phosphatidylethanolamine-binding protein 4 (PEBP4) in invasion and metastasis of non-small cell lung cancer (NSCLC). PEBP4 mRNA and protein expression in 56 cases of NSCLC tissues were detected using RT-PCR and Western blot, and the relationship between PEBP4 expression and invasion and metastasis of NSCLC was analyzed. The change in the invasive ability of human NSCLC cell line HCC827 was observed after knocking down PEBP4 expression using RNA interference. PEBP4 mRNA and protein expression in cancer tissues of patients with lymph node metastasis were significantly higher than those in patients without lymph node metastasis (p < 0.05). PEBP4 expression significantly decreased in HCC827 cells after transfection with PEBP4 siRNA (p < 0.01), and the number of HCC827 cells that migrated through Transwell chambers was significantly lower than that of non-transfected control and transfected control cells (p < 0.01). PEBP4 over-expression may promote the invasion and metastasis of NSCLC.

The expression of PEBP4 protein in lung squamous cell carcinoma.

The phosphatidylethanolamine-binding protein 4 (PEBP4) is a member of the PEBP family. It not only plays a role in the inhibition of the MAPK signaling pathway but also is involved in the inhibition of the JNK pathway that promotes the activation of AKT. Recent research has also shown that overexpression of PEBP4 was related to the development, invasion, and metastasis of a variety of tumors. This study aimed to investigate the correlation between PEBP4 protein expression in lung squamous cell carcinoma tissue and the clinical pathology of lung squamous cell carcinoma. Immunohistochemistry was used to detect PEBP4 expression in lung squamous cell carcinoma tissue and adjacent normal tissue from 61 patients. Western blotting was used to detect changes in the expression of PEBP4 protein between lung squamous cell carcinoma tissue and adjacent normal tissues. The correlation of PEBP4 expression and the occurrence, development, and clinical pathology of lung squamous cell carcinoma was analyzed. Of 61 patients, four patients were PEBP4 negative (-; 6.6%) and 57 patients were positive (+ to +++; 93.4%). Of those positive for PEBP4 expression, 7 patients were weakly positive (+; 11.5%), 21 patients were positive (++; 34.4%), and 29 patients were strongly positive (+++; 47.5%). PEBP4 protein was more highly expressed in lung squamous cell carcinoma tissue than in the adjacent normal lung tissue (p < 0.05). In PEBP4-positive patients, PEBP4 protein expression was significantly greater in those with lymph node metastases than in those without (p < 0.05). PEBP4 expression was significantly lower in patients at early (I and II) stages than in patients at advanced (III and IV) stages (p < 0.05). In less differentiated lung squamous cell carcinomas, PEBP4 protein expression was greater (p < 0.05); however, this was unrelated to the gender, age, or tumor size of the patient (p > 0.05). PEBP4 protein overexpression was associated with the occurrence, invasion, and metastasis of lung squamous cell carcinoma.

Expression and clinical significance of the DNA repair enzyme MYH in esophageal squamous cell carcinoma.

MYH is an important enzyme in combating DNA oxidative stress in the occurrence and development of various types of tumors. To investigate the correlation between expression of the DNA repair enzyme MYH in esophageal squamous cell carcinoma and 8-oxoguanine (8-oxoG) oxidative damage, as well as the clinical significance of altered MYH expression, tissues from 175 esophageal carcinoma cases were investigated in the present study. MYH expression and 8-oxoG oxidative damage in squamous cell carcinoma and adjacent normal tissue were assessed by immunohistochemistry and Western blotting. In 82.9% (145/175) of the cases, MYH protein expression in esophageal squamous cell carcinoma was lower than that of adjacent normal tissue (t=4.24, P<0.001). Additionally, 8-oxoG staining was higher in the tumors than in the normal tissue. Lower expression of MYH in esophageal squamous cell carcinoma was associated with depth of invasion, venous invasion, TNM stage and lymph node metastasis (P<0.05). In conclusion, a lower MYH expression level in esophageal cell carcinoma tissue was inversely associated with more severe 8-oxoG oxidative damage, suggesting that changes in MYH activity correspond to increased DNA damage in tumor cells. The use of MYH expression as a postoperative index for esophageal squamous cell carcinoma may guide the formulation of individualized chemotherapy for patients after surgery.