In vitro investigation of ultrasound-induced oxidative stress on human lens epithelial cells.

The effect of ultrasound exposure on human lens epithelial cells (HLE-B3) was investigated in vitro, specifically on the generation of oxidative stress upon ultrasound application using various clinically-relevant settings. In addition to ultrasound-induced heat effects, oxidative stress has been recently proposed as one of the main mechanisms for ultrasound-induced effects on human cells. In this work, the levels of biocompatibility and generation of oxidative stress by exposure of ultrasound to HLE-B3 were evaluated quantitatively and qualitatively by the MTT assay, Live/Dead assay, reactive oxygen species (ROS) and intracellular calcium level. Oxidative stress induction is traditionally achieved through administrations of H2O2 and thus the administration of H2O2 was used as the positive control group for comparison herein. Concerning the administrations of H2O2 are considered invasive and may potentially have side effects, ultrasound as physical stimulation could be a safer and non-invasive method to induce similar oxidative stress environments. The effect of ultrasound on cell viability and induction of oxidative stress increases with ultrasound intensity. The result reveals that the continuous ultrasound has a positive impact on the oxidative stress levels but does negatively on the cell viability, as compared to the pulsed ultrasound. Furthermore, our work demonstrates that the exposure of 58 kPa continuous ultrasound without microbubbles can maintain acceptable cell viability and produce oxidative stress effects similar to the traditional administrations of H2O2. In summary, exposure of ultrasound can generate oxidative stress comparable to traditional administrations of H2O2. The effect of generating oxidative stress is adjustable through ultrasound parameters, including the pulsed or continuous wave, the intensity of ultrasound and addition of microbubbles.

Roles of HDAC2, eIF5, and eIF6 in Lung Cancer Tumorigenesis.

OBJECTIVE: The expression levels of histone deacetylase 2 (HDAC2), eukaryotic initiation factor 5 (eIF5), and eukaryotic initiation factor 6 (eIF6), and relationship between HDAC2 and eIF5 or eIF6 in lung cancer tissues were investigated, in order to charify the relationship between HDAC2 and the prognosis of lung cancer patients and its influence on the expression of eIF5 and eIF6. METHODS: The expression of HDAC2, eIF5, and eIF6 in lung cancer tissues was detected by quantitative reverse transcription polymerase chain reaction. The expression correlation between HDAC2 and eIF5 or eIF6 was tested using a t test. The correlation between HDAC2 and eIF5 or eIF6 was analyzed using the TCGA database. The identified cells were constructed with small interfering siRNA and HDAC2 overexpression plasmid. The proliferation and migration ability of the identified cells was investigated by CCK8 and Transwell assays, respectively. RESULTS: HDAC2, eIF5, and eIF6 were overexpressed in lung cancer tissues, and HDAC2 expression level was negatively correlated with the prognosis of lung cancer patients. HDAC2 expression level was positively correlated with eIF5 and eIF6 expression levels. HDAC2 could regulate the expression of eIF5 and eIF6. The regulation of proliferation and invasion of lung cancer cells by HDAC2 depended on eIF5 and eIF6. CONCLUSION: HDAC2, eIF5, and eIF6 were closely related with lung cancer tumorigenesis, which might be potential biological markers and therapeutic targets for lung cancer.

Overexpression of c-Ski promotes cell proliferation, invasion and migration of gastric cancer associated fibroblasts.

The present study aimed to investigate the effects of c-Ski on cell proliferation, invasion and migration of gastric cancer associated fibroblasts (CAFs). Expression of c-Ski in gastric cancer (GC) tissues was determined using immunohistochemistry. Both CAFs and non-cancerous gastric fibroblasts (NGFs) were isolated and cultured. c-Ski and Smad3 were over-expressed or knocked down using pcDNA3.0-c-Ski/Smad3 or siRNA, respectively. Cell viability, invasion and migration were measured and expression of c-Ski, α-SMA, and Smad3 in cells was determined using real time quantitative PCR (RT-qPCR) and Western blotting. Expression of c-Ski was significantly higher in both in GC tissues and cell lines, and was the highest in tissues of diffuse type. Both c-Ski and α-SMA were significantly over-expressed in CAFs compared with that in the NGFs. When c-Ski was over-expressed in NGFs, cell viability, cell invasion and migration were all enhanced and expression of Smad3 was downregulated. When c-Ski was inhibited, cell viability, cell invasion, and migration were all suppressed and expression of Smad3 was upregulated. Meanwhile, overexpression of Smad3 significantly reversed the effects of over-expressed c-Ski in NGFs, and knockdown of Smad3 dramatically reversed the effects of si-c-Ski in CAFs. Over-expressed c-Ski could enhance cell viability, promote cell invasion, and migration of GC CAFs, and the effects might be through regulation of Smad3 signaling. This study may give deeper insights for relationship between c-Ski and CAFs, as well as role of c-Ski in cancer development, and also provide some novel research targets for treatment of GC.

[Treatment of advanced metastatic breast cancer with exemestane, a multicenter randomized controlled study of 195 cases].

OBJECTIVE: To observe the efficacy of exemestane for postmenopausal advanced metastatic breast cancer, and to assess its side effects. METHODS: A randomized, double-blind, and parallel controlled study was conducted among 195 patients with postmenopausal advanced metastatic breast cancer from December 2001 to June 2002. Except for the 4 cases who were lost to follow-up, the remaining 191 patients were divided into two groups: study group (n = 96, treated with exemestane capsule 25 mg and one model tablet of letrozole orally q.d. for 8 weeks), and control group (n = 95, treated with letrozole 2.5 mg and one model capsule of exemestane orally q.d. for 8 weeks). Physical examination, roentgenography and CT were conducted to observe the outcome of the tumor and the level of estrogen was tested 2 weeks before and 4 and 8 weeks after the beginning of treatment. RESULTS: The effective rate was 44.8% in the study group and 45.3% in the control group (P = 0.971). The level of estradiol was 5.17 +/- 6.68 x 10(4) pg/L and 4.19 +/- 3.06 x 10(4) pg/L in the study group and control group respectively; and was 3.08 +/- 2.80 x 10(4) pg/L and 2.76 +/- 1.98 x 10(4) pg/L in the study group and control group respectively 8 weeks after the beginning of treatment, both decreased by 43.7% in comparison with those before treatment (both P < 0.001), however, there was no significant difference between the study group and control group (P = 0.141). The side effects of exemestane included thirst, giddiness, and nausea. CONCLUSION: An effective hormonal medicine, exemestane has good therapeutic efficacy in postmenopausal advanced metastatic breast cancer with only mild side effects.