T4 reduces cisplatin resistance by inhibiting AEG-1 gene expression in lung cancer cells.

Lung cancer is the most malignant form of cancer and has the highest morbidity and mortality worldwide. Due to drug resistance, the current chemotherapy for lung cancer is not effective and has poor therapeutic effects. Tripchlorolide (T4), a natural extract from the plant Tripterygium wilfordii, has powerful immunosuppressive and antitumour effects and may become a potential therapeutic agent for lung cancer. Therefore, this study aimed to investigate the effect of T4 on reducing chemoresistance in lung cancer cells and to explore the mechanism. 1. A549 and A549/DDP cells were separately transfected with AEG-1 overexpression and AEG-1 knockdown plasmids. A549/DDP cells were divided into the A549/DDP empty group, T4 group, and T4 + AEG-1 overexpression group. A CCK-8 assay was used to evaluate the proliferation of cells in each group. RT-qPCR and Western blotting were used to detect the expression of AEG-1 and MDR-1. Expression of AEG-1 in A549 and A549/DDP cells was positively correlated with cisplatin resistance. When the AEG-1 protein was overexpressed in A549 cells, the lethal effect of cisplatin on A549 cells was attenuated (all P < 0.05). After the AEG-1 protein was knocked down in A549/DDP cells, cisplatin was applied. The lethal effect was significantly increased compared to that in the corresponding control cells (all P < 0.05). AEG-1 protein expression gradually decreased with increasing T4 concentration in A549 and A549/DDP cells. Resistance to cisplatin was reduced after the addition of T4 to A549/DDP cells (P < 0.05), and this effect was enhanced after transfection with the AEG-1 knockdown plasmid. T4 plays an important role in increasing the sensitivity of lung cancer cells to cisplatin.

Parent Cognitive Satisfaction and Demand Research of Neonatal Hearing Screening.

The primary aim of the present study was to investigate parent cognitive satisfaction and demand by using a valid and reliable questionnaire developed for this purpose (Parent Cognitive Satisfaction and Demand Questionnaire with Neonatal Hearing Screening Program, PCSDQ-NHSP). About 1000 parents whose children received hearing screening participated in this study. The satisfaction questionnaire was found to be a useful instrument for identifying service shortfalls, and the routine use of the PCSDQ-NHSP in other neonatal hearing screening programs is recommended. Overall, parents focused their attention to the neonatal hearing screening results and had high levels of expectations. They also longed for more information about relevant knowledge. Screening ability differed in different areas of Guangdong province where grass-roots hospitals had poor ability to perform this well. More preappointment information leaflets or brochures should be sent to parents. Regular training for neonatal hearing screening test is needed in primary hospitals. We can establish a neonatal hearing screening network to link as many hospitals as possible, and develop a standardized neonatal hearing screening system.

Synthesis and Antitumor Properties of BQC-Glucuronide, a Camptothecin Prodrug for Selective Tumor Activation.

Major limitations of camptothecin anticancer drugs (toxicity, nonselectivity, water insolubility, inactivation by human serum albumin) may be improved by creating glucuronide prodrugs that rely on beta-glucuronidase for their activation. We found that the camptothecin derivative 5,6-dihydro-4H-benzo[de]quinoline-camptothecin (BQC) displays greater cytotoxicity against cancer cells than the clinically used camptothecin derivatives SN-38 and topotecan even in the presence of human serum albumin. We synthesized the prodrug BQC-glucuronide (BQC-G), which was 4000 times more water soluble and 20-40 times less cytotoxic than BQC. Importantly, even in the presence of human serum albumin, BQC-G was efficiently hydrolyzed by beta-glucuronidase and produced greater cytotoxicity (IC50 = 13 nM) than camptothecin, 9-aminocamptothecin, SN-38, or topotecan (IC50 > 3000, 1370, 48, and 28 nM, respectively). BQC-G treatment of mice bearing human colon cancer xenografts with naturally or artificially elevated beta-glucuronidase activity produced significant antitumor activity, showing that BQC-G is a potent prodrug suitable for selective intratumoral drug activation.

Effect of Cellular Location of Human Carboxylesterase 2 on CPT-11 Hydrolysis and Anticancer Activity.

CPT-11 is an anticancer prodrug that is clinically used for the treatment of metastatic colorectal cancer. Hydrolysis of CPT-11 by human carboxylesterase 2 (CE2) generates SN-38, a topoisomerase I inhibitor that is the active anti-tumor agent. Expression of CE2 in cancer cells is under investigation for the tumor-localized activation of CPT-11. CE2 is normally expressed in the endoplasmic reticulum of cells but can be engineered to direct expression of active enzyme on the plasma membrane or as a secreted form. Although previous studies have investigated different locations of CE2 expression in cancer cells, it remains unclear if CE2 cellular location affects CPT-11 anticancer activity. In the present study, we directly compared the influence of CE2 cellular location on substrate hydrolysis and CPT-11 cytotoxicity. We linked expression of CE2 and enhanced green fluorescence protein (eGFP) via a foot-and-mouth disease virus 2A (F2A) peptide to facilitate fluorescence-activated cell sorting to achieve similar expression levels of ER-located, secreted or membrane-anchored CE2. Soluble CE2 was detected in the medium of cells that expressed secreted and membrane-anchored CE2, but not in cells that expressed ER-retained CE2. Cancer cells that expressed all three forms of CE2 were more sensitive to CPT-11 as compared to unmodified cancer cells, but the membrane-anchored and ER-retained forms of CE2 were consistently more effective than secreted CE2. We conclude that expression of CE2 in the ER or on the membrane of cancer cells is suitable for enhancing CPT-11 anticancer activity.

Effects of an Al(3+)- and Mg(2+)-containing antacid, ferrous sulfate, and calcium carbonate on the absorption of nemonoxacin (TG-873870) in healthy Chinese volunteers.

AIM: To evaluate the effects of an Al(3+)- and Mg(2+)-containing antacid, ferrous sulfate, and calcium carbonate on the absorption of nemonoxacin in healthy humans. METHODS: Two single-dose, open-label, randomized, crossover studies were conducted in 24 healthy male Chinese volunteers (12 per study). In Study 1, the subjects orally received nemonoxacin (500 mg) alone, or an antacid (containing 318 mg of Al(3+) and 496 mg of Mg(2+)) plus nemonoxacin administered 2 h before, concomitantly or 4 h after the antacid. In Study 2, the subjects orally received nemonoxacin (500 mg) alone, or nemonoxacin concomitantly with ferrous sulfate (containing 60 mg of Fe(2+)) or calcium carbonate (containing 600 mg of Ca(2+)). RESULTS: Concomitant administration of nemonoxacin with the antacid significantly decreased the area under the concentration-time curve from time 0 to infinity (AUC0-∞) for nemonoxacin by 80.5%, the maximum concentration (Cmax) by 77.8%, and urine recovery (Ae) by 76.3%. Administration of nemonoxacin 4 h after the antacid decreased the AUC0-∞ for nemonoxacin by 58.0%, Cmax by 52.7%, and Ae by 57.7%. Administration of nemonoxacin 2 h before the antacid did not affect the absorption of nemonoxacin. Administration of nemonoxacin concomitantly with ferrous sulfate markedly decreased AUC0-∞ by 63.7%, Cmax by 57.0%, and Ae by 59.7%, while concomitant administration of nemonoxacin with calcium carbonate mildly decreased AUC0-∞ by 17.8%, Cmax by 14.3%, and Ae by 18.4%. CONCLUSION: Metal ions, Al(3+), Mg(2+), and Fe(2+) markedly decreased the absorption of nemonoxacin in healthy Chinese males, whereas Ca(2+) had much weaker effects. To avoid the effects of Al(3+) and Mg(2+)-containing drugs, nemonoxacin should be administered ≥2 h before them.

Recurrent chemical reactivations of EBV promotes genome instability and enhances tumor progression of nasopharyngeal carcinoma cells.

Nasopharyngeal carcinoma (NPC) is an endemic malignancy prevalent in South East Asia. Epidemiological studies have associated this disease closely with Epstein-Barr virus (EBV) infection. Previous studies also showed that EBV reactivation is implicated in the progression of NPC. Thus, we proposed that recurrent reactivations of EBV may be important for its pathogenic role. In this study, NPC cell lines latently infected with EBV, NA and HA, and the corresponding EBV-negative NPC cell lines, NPC-TW01 (TW01) and HONE-1, were treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) and sodium n-butyrate (SB) for lytic cycle induction. A single treatment with TPA/SB revealed that DNA double-strand breaks and formation of micronuclei (a marker for genome instability) were associated with EBV reactivation in NA and HA cells. Examination of EBV early genes had identified several lytic proteins, particularly EBV DNase, as potent activators that induced DNA double-strand breaks and contribute to genome instability. Recurrent reactivations of EBV in NA and HA cells resulted in a marked increase of genome instability. In addition, the degree of chromosomal aberrations, as shown by chromosome structural variants and DNA copy-number alterations, is proportional to the frequency of TPA/SB-induced EBV reactivation. Whereas these DNA abnormalities were limited in EBV-negative TW01 cells with mock or TPA/SB treatment, and were few in mock-treated NA cells. The invasiveness and tumorigenesis assays also revealed a profound increase in both characteristics of the repeatedly reactivated NA cells. These results suggest that recurrent EBV reactivations may result in accumulation of genome instability and promote the tumor progression of NPC.