Wenshan He

Acquired cisplatin resistance in human lung adenocarcinoma cells is associated with enhanced autophagy.

Activation of autophagy is a hallmark in tumor cells treated with chemotherapy, but the role of autophagy in acquired resistance of lung adenocarcinoma to cisplatin-based chemotherapy remains to be clarified. Our aim was to address that question by surveying the autophagic activity in parental lung adenocarcinoma cell line A549 and its 8-fold, more resistant subcell line, A549/DDP, which was obtained by treating cisplatin with increasing concentrations. A549/DDP and A549 cells were exposed to serum-free culture medium or ionizing radiation. To measure the stress-induced autophagy, LC3-II, as an autophagosome marker, was measured by immunofluorescence and Western blotting. To determine the effect of 3-MA, a known inhibitor of autophagy, on overcoming acquired cisplatin resistance, the MTT assay and flow cytometry were performed. Western blotting analysis demonstrated that LC3-II was increased in A549/DDP cells, compared with those of parental A549 cells, under stress conditions. Meanwhile, immunofluorescence staining showed that LC3-II protein was located mainly in the cytoplasm of A549/DDP. We also found that 3-MA can enhance the growth inhibition and apoptotic effect of cisplatin in acquired resistant cells (A549/DDP). Collectively, our results provide evidence that the upregulation of autophagy plays a major role in cisplatin resistance of A549/DDP cells.

Lysyl Oxidase 473 G>A Polymorphism and Breast Cancer Susceptibility in Chinese Han Population

Lysyl oxidase (LOX) is an extracellular enzyme critical for the cross-linking of collagens and elastin. The LOX gene has also been shown to inhibit the transforming activity of Ras oncogene signaling. Recently, a single-nucleotide polymorphism (SNP) of LOX G473A (rs1800449) has been demonstrated to be associated with increased risk of breast cancer in African American women. In this hospital-based case-control study, the association of LOX polymorphism with breast cancer susceptibility in Chinese Han population was investigated. In total, 238 female patients with breast cancer and 234 age-matched healthy controls recruited were genotyped. We found a significant difference in the frequency of the LOX G473A genotype between the breast cancer and control groups. Individuals with GA genotype showed a 2.79-fold (95% confidence interval = 1.87-4.16) increased risk of breast cancer compared with subjects carrying GG genotype (p < 0.001). Further statistical analysis revealed that this polymorphism was an independent parameter with regard to other variables that are significantly associated with breast cancer, that is, age, menopausal status, estrogen exposure interval, expression status of estrogen receptor, and progesterone receptor. These findings suggest that the LOX 473 GA genotype is independently associated with increased risk of breast cancer in Chinese female population.

EGFR mutations in non-small-cell lung cancer among smokers and non-smokers: A meta-analysis

Mounting evidence has suggested somatic mutations in the EGFR gene are associated with better responsiveness to EGFR tyrosine kinase inhibitors (TKIs) in patients with non‐small‐cell lung cancer (NSCLC). Some, but not all, studies have reported that the mutations were more frequently observed in patients without a smoking history. To comprehensively address this issue, we performed a meta‐analysis to evaluate the association between cigarette‐smoking history and mutation of the EGFR gene in NSCLC. Twenty‐six studies, involving 3,688 patients with NSCLC were included in the analysis. The pooled analysis shows that the incidence of EGFR mutations in NSCLC differs according to cigarette‐smoking history. The odds ratio (OR) for the EGFR mutation in non‐smokers relative to smokers was 4.829 (95% confidence interval [CI]: 3.598–6.482; P < 0.001). These data may assist clinicians in assessing the likelihood of EGFR mutations in patients with NSCLC when mutational analysis is not feasible. Environ. Mol. Mutagen. 2012.

RASSF2A promoter methylation in hepatitis B virus-related hepatocellular carcinogenesis and its correlation with elevated serum α-fetoprotein level

SummaryLoss of the RASSF2A expression induced by methylation-mediated silencing has been reported in several human cancers, but the methylation status of RASSF2A in hepatocellular carcinoma (HCC) is rarely studied so far. In this study, we investigated the RASSF2A expression and its methylation status in a cohort of 45 hepatitis B virus-associated HCC tissues and their adjacent non-carcinoma tissues by using RT-PCR and MS-PCR. Promoter methylation of RASSF2A was found in 31 (68.9%) out of 45 HCC tissues and 12 (40%) out of 30 adjacent normal tissues, respectively (P<0.05). The methylation status of PASSF2A was closely associated with the loss of RASSF2A expression and elevated serum α-fetoprotein level, but not significantly with clinical stage, hepatic fibrosis and K-ras mutation. It was concluded that aberrant methylation of the RASSF2A gene with the subsequent loss of RASSF2A expression plays an important role in the pathogenesis of HCC.Loss of the RASSF2A expression induced by methylation-mediated silencing has been reported in several human cancers, but the methylation status of RASSF2A in hepatocellular carcinoma (HCC) is rarely studied so far. In this study, we investigated the RASSF2A expression and its methylation status in a cohort of 45 hepatitis B virus-associated HCC tissues and their adjacent non-carcinoma tissues by using RT-PCR and MS-PCR. Promoter methylation of RASSF2A was found in 31 (68.9%) out of 45 HCC tissues and 12 (40%) out of 30 adjacent normal tissues, respectively (P<0.05). The methylation status of PASSF2A was closely associated with the loss of RASSF2A expression and elevated serum α-fetoprotein level, but not significantly with clinical stage, hepatic fibrosis and K-ras mutation. It was concluded that aberrant methylation of the RASSF2A gene with the subsequent loss of RASSF2A expression plays an important role in the pathogenesis of HCC.

Association between CHRNA3 rs1051730 genotype and lung cancer risk in Chinese Han population: A case-control study

SummaryRecent population-based genome wide association studies have revealed potential susceptibility loci of lung cancer at the region of chromosome 15q25.1 containing nicotinic acetylcholine receptor genes. The loci increasing lung cancer risk has been widely identified in Caucasians, but whether this association also exists in Asians and whether this association is a direct role or mediated via tobacco smoking indirectly has not been fully established. We conducted a case-control study comprising of 210 histologically confirmed lung cancer cases and 200 healthy controls to examine rs1051730 genotyping, a single nucleotide polymorphism receiving much attention recently, and its influence on lung cancer risk as well as nicotine dependence in a Chinese Han population. Our results showed that the heterozygous C/T genotype and minor allele T conferred a significant higher risk of lung cancer than the CC homozygotes and allele C (adjusted OR=2.25, 95% CI=1.04–4.89, P=0.040 and OR=2.18, 95% CI=1.02–4.67, P=0.045 respectively). However, no association between the smoking habit and the CHRNA3 rs1051730 polymorphism was observed in this study. The results suggested that the rs1051730 polymorphism may modify susceptibility to lung cancer via a smoking-independent manner among Chinese Han population. Additional studies in vitro and in vivo are warranted to further elucidate the impact of rs1051730 on lung cancer susceptibility.Recent population-based genome wide association studies have revealed potential susceptibility loci of lung cancer at the region of chromosome 15q25.1 containing nicotinic acetylcholine receptor genes. The loci increasing lung cancer risk has been widely identified in Caucasians, but whether this association also exists in Asians and whether this association is a direct role or mediated via tobacco smoking indirectly has not been fully established. We conducted a case-control study comprising of 210 histologically confirmed lung cancer cases and 200 healthy controls to examine rs1051730 genotyping, a single nucleotide polymorphism receiving much attention recently, and its influence on lung cancer risk as well as nicotine dependence in a Chinese Han population. Our results showed that the heterozygous C/T genotype and minor allele T conferred a significant higher risk of lung cancer than the CC homozygotes and allele C (adjusted OR=2.25, 95% CI=1.04–4.89, P=0.040 and OR=2.18, 95% CI=1.02–4.67, P=0.045 respectively). However, no association between the smoking habit and the CHRNA3 rs1051730 polymorphism was observed in this study. The results suggested that the rs1051730 polymorphism may modify susceptibility to lung cancer via a smoking-independent manner among Chinese Han population. Additional studies in vitro and in vivo are warranted to further elucidate the impact of rs1051730 on lung cancer susceptibility.

In vitro chemosensitivity testing of primary and recurrent breast carcinomas and its clinical significance

SummaryIn this study, in vitro chemosensitivity testing was conducted on primary cultured breast cancer cells from 96 patients with breast cancer, and the results showed that the cells from a few patients with primary breast cancer developed multidrug resistance (MDR) prior to the first chemotherapy exposure. All the cells from the recurrent cancer patients had MDR. The findings suggested that patients having MDR would benefit from high-dose chemotherapy (HDC) regimens. In vitro chemosensitivity screening, which was aimed at improving the therapeutic efficacy and minimizing side effects, helps in choosing individualized treatment for breast cancer.In this study, in vitro chemosensitivity testing was conducted on primary cultured breast cancer cells from 96 patients with breast cancer, and the results showed that the cells from a few patients with primary breast cancer developed multidrug resistance (MDR) prior to the first chemotherapy exposure. All the cells from the recurrent cancer patients had MDR. The findings suggested that patients having MDR would benefit from high-dose chemotherapy (HDC) regimens. In vitro chemosensitivity screening, which was aimed at improving the therapeutic efficacy and minimizing side effects, helps in choosing individualized treatment for breast cancer.

Methotrexate-Loaded Extracellular Vesicles Functionalized with Therapeutic and Targeted Peptides for the Treatment of Glioblastoma Multiforme

Despite promising in vitro evidence for effective glioblastoma treatment, most drugs are hindered from entering the central nervous system because of the presence of the blood-brain barrier (BBB). Thus, successful modification of drug delivery and novel therapeutic strategies are needed to overcome this obstacle. Extracellular vesicles (EVs), cell-derived membrane-encapsulated structures with diameters ranging from 50 to 1000 nm, have been explored as the drug delivery system to deliver their cargo to the brain tissue. Moreover, tumor targeting and selective drug delivery has been facilitated by engineering their parent cells to secrete modified EVs. However, the method suffers from many shortcomings including poor repeatability and complex and time-consuming operations. In this context, we present an easy-to-adapt and highly versatile methodology to modify EVs with an engineered peptide capable of recognition and eradication of glioma. On the basis of molecular recognition between phospholipids on EV lipid bilayer membranes and ApoA-I mimetic peptides, we have developed methotrexate (MTX)-loaded EVs functionalized with therapeutic [Lys-Leu-Ala (KLA)] and targeted [low-density lipoprotein (LDL)] peptides. In vitro experiments demonstrated that EVs decorated with LDL or KLA-LDL could obviously ameliorate their uptake by human primary glioma cell line U87 and permeation into three-dimensional glioma spheroids in contrast to blank EVs, and consequently, the treatment outcome of the payload is improved. Both ex vivo and in vivo imaging experiments revealed that peptide LDL could obviously promote EV extravasation across the BBB and distribution in the glioma site. Furthermore, compared with the mice administrated with MTX and MTX@EVs, MTX@EVs-KLA-LDL-treated mice showed the longest median survival period. In conclusion, functionalizing with the peptide onto EV surfaces may provide a substantial advancement in the application of EVs for selective target binding as well as therapeutic effects for brain tumor treatment.

Relationship between expression of vascular endothelial growth factor and cervical lymph node metastasis in papillary thyroid cancer: A meta-analysis

The aim of the present study was to examine the relationship between the protein expression of vascular endothelial growth factor (VEGF) and lymph node metastasis (LNM) in papillary thyroid cancer (PTC). VEGF-related articles that had been published until August 2016 were searched from the PubMed, EMBASE, and MEDLINE to identify the risk factors of LNM in PTC. RevMan 5.3 software was used for the meta-analysis. Finally, 9 articles met the inclusion criteria and were included in our meta-analysis. LNM was found to be present in 176 of 318 patients (57.8%) with high VEGF expression and in 71 of 159 patients (47.0%) with low VEGF expression. The overall OR was 2.81 (95% confidence interval, 1.49–5.29). LNM occurred more frequently in patients with high VEGF expression than in those with low VEGF expression (P=0.001). Heterogeneity was markedly decreased in the subgroup analyses of LNM in terms of the patients’ country of origin and the detection methods. Our meta- analysis concluded that the VEGF protein expression is associated with LNM in PTC.SummaryThe aim of the present study was to examine the relationship between the protein expression of vascular endothelial growth factor (VEGF) and lymph node metastasis (LNM) in papillary thyroid cancer (PTC). VEGF-related articles that had been published until August 2016 were searched from the PubMed, EMBASE, and MEDLINE to identify the risk factors of LNM in PTC. RevMan 5.3 software was used for the meta-analysis. Finally, 9 articles met the inclusion criteria and were included in our meta-analysis. LNM was found to be present in 176 of 318 patients (57.8%) with high VEGF expression and in 71 of 159 patients (47.0%) with low VEGF expression. The overall OR was 2.81 (95% confidence interval, 1.49–5.29). LNM occurred more frequently in patients with high VEGF expression than in those with low VEGF expression (P=0.001). Heterogeneity was markedly decreased in the subgroup analyses of LNM in terms of the patients’ country of origin and the detection methods. Our meta- analysis concluded that the VEGF protein expression is associated with LNM in PTC.