Association of genetic and immuno-characteristics with clinical outcomes in patients with RET-rearranged non-small cell lung cancer: a retrospective multicenter study.

BACKGROUND: Rearranged during transfection (RET) has been proven to be a tumorigenic target in non-small cell lung cancers (NSCLCs). In RET-rearranged NSCLCs, molecular features and their impact on prognosis were not well illustrated, and the activity of mainstay therapeutics has not currently been well compared. METHODS: Patients diagnosed with NSCLCs with RET rearrangements were analyzed for concomitant mutations, tumor mutation burden (TMB), PD-L1 expression, T cell receptor repertoire and clinical outcomes with chemotherapy, immune checkpoint inhibitors (ICIs), and multikinase inhibitors (MKIs). RESULTS: Among 129 patients with RET-rearranged NSCLC who were analyzed, 41.1% (53/129) had co-occurring genetic alterations by next-generation sequencing, and concomitant TP53 mutation appeared most frequently (20/53, 37.7%). Patients with concurrent TP53 mutation (n = 15) had shorter overall survival than those without (n = 30; median, 18.4 months [95% CI, 8.6-39.1] vs 24.8 months [95% CI, 11.7-52.8]; P < 0.05). Patients with lower peripheral blood TCR diversity (n = 5) had superior overall survival compared with those with higher diversity (n = 6; median, 18.4 months [95% CI, 16.9-19.9] vs 4.8 months [95% CI, 4.5-5.3]; P = 0.035). An association with overall survival was not observed for PD-L1 expression nor for tumor mutation burden level. Median progression-free survival was not significantly different across chemotherapy, ICIs, and MKIs (median, 3.5 vs 2.5 vs 3.8 months). For patients treated with ICIs, the disease control rate was 60% (6/10) and the objective response rate was 20% (2/10). CONCLUSIONS: RET-rearranged lung cancers can be heterogeneous in terms of concomitant genetic alterations. Patients with concurrent TP53 mutation or high peripheral blood TCR repertoire diversity have relatively inferior overall survival in this series. Outcomes with traditional systemic therapies in general are suboptimal.

Down-regulation of deacetylase HDAC6 inhibits the melanoma cell line A375.S2 growth through ROS-dependent mitochondrial pathway.

Previous studies have shown that histone deacetylase 6 (HDAC6) plays critical roles in many cellular processes related to cancer. However, its biological roles in the development of melanoma remain unexplored. Our aim was to investigate whether HDAC6 has a biological role in human melanoma development and to understand its underlying mechanism. In the present study, HDAC6 expression was up-regulated in melanoma tissues and cell lines. Knockdown of HDAC6 significantly inhibited the proliferation and colony formation ability of A375.S2 cells, promoted cell arrest at G0/G1 phase and apoptosis. Additionally, western blotting assay showed that HDAC6 silencing suppressed Bcl-2 level and enhanced Bax level, then activated caspase-9 and caspase-3, and further activated the release of cytochrome c from mitochondria to cytoplasm, finally induced cell apoptosis involving the mitochondrial pathway. Knockdown of HDAC6 triggered a significant generation of ROS and disruption of mitochondrial membrane potential (MMP). Furthermore, ROS inhibitor, NAC reduced HDAC6 siRNA-induced ROS production, and blocked HDAC6 siRNA-induced loss of MMP and apoptosis. NAC also significantly blocked HDAC6 siRNA-induced mtDNA copy number decrease and mitochondrial biogenesis and degradation imbalance. In conclusion, the results showed that knockdown of HDAC6 induced apoptosis in human melanoma A375.S2 cells through a ROS-dependent mitochondrial pathway.

Anti-angiogenesis effect of generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide on breast cancer in vitro.

OBJECTIVE: To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAM/VEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. METHODS: We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. RESULTS: The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. CONCLUSION: With a low toxicity, high safety, and high transfection rate, G4PAMAM/VEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.

Combined treatment of oxaliplatin and capecitabine in patients with metastatic esophageal squamous cell cancer.

AIM: To investigate the efficacy and side effects of the combined therapy of oxaliplatin and capecitabine in patients with metastatic esophageal squamous cell cancer (ESCC) and the survival of the patients. METHODS: Sixty-four patients (median age of 63 years) with histological or cytological confirmation of ESCC received oxaliplatin 120 mg/m(2) intravenously on day 1 and capecitabine 1000 mg/m(2) orally twice daily on days 1 to 14 in a 21-d treatment cycle as palliative chemotherapy. Each patient received at least two cycles of treatment. The efficacy, side effects and patient survival were evaluated. RESULTS: The partial response (PR) rate was 43.8% (28/64). Stable disease (SD) rate was 47.9% (26/64), and disease progression rate was 15.6% (10/64). The clinical benefit rate (PR + SD) was 84.4%. The main toxicities were leukopenia (50.0%), nausea and vomiting (51.6%), diarrhea (50.0%), stomatitis (39.1%), polyneuropathy (37.5%) and hand-foot syndrome (37.5%). No grade 4 event in the entire cohort was found. The median progression-free survival was 4 mo, median overall survival was 10 mo (95% CI: 8.3-11.7 mo), and the 1- and 2-year survival rates were 38.1% and 8.2%, respectively. High Karnofsky index, single metastatic lesion and response to the regimen indicated respectively good prognosis. CONCLUSION: Oxaliplatin plus capecitabine regimen is effective and tolerable in metastatic ESCC patients. The regimen has improved the survival moderately and merits further studies.

[Anti-angiogenesis effect of G4PAMAM/VEGFASODN on breast cancer in vitro].

OBJECTIVE: To investigate the effect of G4PAMAM/VEGFASODN compound on expression of VEGF and VEGF mRNA in MDA-MB-231 breast cancer cells and the growth inhibition of vascular endothelial cells. METHODS: The diameter of G4PAMAM/VEGFASODN granule was measured by transmission electron microscopy, and its stability under different pH was also observed. The efficiency of transfection in vitro was detected by flow cytometer and the positively transfected cells were detected by laser scanning confocal microscope. The survival rate and the inhibitory rate of vascular endothelial cells were determined by MTT assay. The expression of protein VEGF was detected by immunohistochemical method and the expression of VEGF mRNA was detected by RT-PCR. RESULT: The diameter of G4PAMAM/VEGFASODN granules was about 10 nm and it arranged as homogeneous netlike. Under pH 5-10 G4PAMAM/VEGFASODN presented highly stable and no dissociation was observed with different charge ratios. The 48-hour transfection rate of G4PAMAM/VEGFASODN in charge ratio of 1:40 was significantly higher than that of the lipofectamine group. None of the transfection products in each group showed cell toxicity. The staining of VEGF protein in the cytoplasm of MDA-MB-231 cells after G4PAMAM/ASODN transfection weakened markedly, and the positive expression rate decreased. Meanwhile, the VEGF mRNA expression was also decreased. CONCLUSION: With good stability and transfection rate, compound G4PAMAM/VEGFASODN can be a promising new nanometer vector of gene transfer system. The G4PAMAM/VEGFASODN can inhibit the expression of VEGF gene specifically and efficiently, which may be used for in vivo animal experiment.