EGFR inhibitor C225 Increases the Radio-Sensitivity of Human Breast Cancer Cells

Functional Nanomedicines for Targeted Therapy of Bladder Cancer

Bladder cancer is one of most common malignant urinary tract tumor types with high incidence worldwide. In general, transurethral resection of non-muscle-invasive bladder cancer followed by intravesical instillation of chemotherapy is the standard treatment approach to minimize recurrence and delay progression of bladder cancer. However, conventional intravesical chemotherapy lacks selectivity for tumor tissues and the concentration of drug is reduced with the excretion of urine, leading to frequent administration and heavy local irritation symptoms. While nanomedicines can overcome all the above shortcomings and adhere to the surface of bladder tumors for a long time, and continuously and efficiently release drugs to bladder cancers. The rapid advances in targeted therapy have led to significant improvements in drug efficacy and precision of targeted drug delivery to eradicate tumor cells, with reduced side-effects. This review summarizes the different available nano-systems of targeted drug delivery to bladder cancer tissues. The challenges and prospects of targeted therapy for bladder cancer are additionally discussed.

Combined treatment with silver graphene quantum dot, radiation, and 17-AAG induces anticancer effects in breast cancer cells

We aimed to investigate the possible anticancer effects of radiation in combination with 17-allylamino-17-demethoxy geldanamycin (17-AAG) and silver graphene quantum dot (SQD) in breast cancer (BC) cells. MCF-7 BC cells treated with, or without, different concentrations of 17-AAG and synthesized SQD and cellular viability detected. The growth inhibitory effects of low concentrations of 17-AAG with minimally toxic concentration of SQD in combination with 2 Gy of X-ray radiation were examined. The apoptosis induction assessed by acridine orange/ethedium bromide staining. Likewise, the levels of lactate, hydrogen peroxide (H₂ O₂ ), nitric oxide (NO) were evaluated. The relative gene expression levels of Bax and Bcl-2 were detected by real-time polymerase chain reaction and the Bax/Bcl-2 expression ratio was determined. Moreover, the protein expression of epidermal growth factor receptor (EGFR) was assessed by western blot analysis. Treatment with low concentrations of 17-AAG and SQD at a minimally toxic concentration promoted inhibition of BC cell growth and induced apoptosis. In addition, significant reduction in cell viability was seen in triple combination versus all double and single treatments. Indeed 17-AAG and SQD in combined with radiation significantly increased the H₂ O₂ and NO versus single and double treated cases. In addition, triple combination treatment showed decreased lactate level in compared tomonotherapies. EGFR protein expression levels were found to decreased in all double and triple combined cases versus single treatments. Additionally, in double and triple treatments, Bax/Bcl2 ratio were higher in compared to single treatments. Treatment with low concentrations of 17-AAG and SQD at a minimally toxic concentration tends to induce anticancer effects and increase the radiation effects when applied with 2 Gy of radiation versus radiation monotherapy.

Differential miRNAs expression pattern of irradiated breast cancer cell lines is correlated with radiation sensitivity

Radiotherapy is a fundamental step in the treatment of breast cancer patients. The treatment efficiency is however reduced by the possible onset of radiation resistance. In order to develop the effective treatment approach, it is important to understand molecular basis of radiosensitivity in breast cancer. The purpose of the present study was to investigate different radiation response of breast cancer cell lines, and find out if this response may be related to change in the microRNAs expression profile. MDA-MB-231 and T47D cells were subjected to different doses of radiation, then MTT and clonogenic assays were performed to assess radiation sensitivity. Cytofluorometric and western blot analysis were performed to gain insight into cell cycle distribution and protein expression. MicroRNA sequencing and bioinformatics prediction methods were used to identify the difference in microRNAs expression between two breast cancer cells and the related genes and pathways. T47D cells were more sensitive to radiation respect to MDA-MB-231 cells as demonstrated by a remarkable G2 cell cycle arrest followed by a greater reduction in cell viability and colony forming ability. Accordingly, T47D cells showed higher increase in the phosphorylation of ATM, TP53 and CDK1 (markers of radiation response) and faster and more pronounced increase in RAD51 and γH2AX expression (markers of DNA damage), when compared to MDA-MB-231 cells. The two cell lines had different microRNAs expression profiles with a confirmed significant differential expression of miR-16-5p, which targets cell cycle related genes and predicts longer overall survival of breast cancer patients, as determined by bioinformatics analysis. These results suggest a possible role for miR-16-5p as radiation sensitizing microRNA and as prognostic/predictive biomarker in breast cancer.

The Effect of PEI-Mediated E1A on the Radiosensitivity of Hepatic Carcinoma Cells

Objective:

The study was undertaken to investigate the effects of polyethyleneimine (PEI)-mediated adenovirus 5 early region 1A (E1A) on radiosensitivity of human hepatic carcinoma cell in vitro and to disclosure the underlying mechanism.

Materials and Methods:

Human hepatic carcinoma SMMC-7721 cell line was transfected with E1A gene using PEI vector. Untransfected cells (SMMC-7721 group), cells transfected with blank-vector (SMMC-7721-vect group), and cells transfected with E1A gene (SMMC-7721-E1A group) were treated with 6 MV X-ray irradiation at doses of 0, 1, 2, 4, 8 and Gy, respectively. Radiosensitivity was determined by MTT assay and quantified by calculating the cell survival rate. Cell-cycle distribution and apotosis rate were monitored by flow cytometry.

Results:

The survival rate of SMMC-7721-E1A was significantly lower than that of SMMC-7721 cell. Apoptosis rate of SMMC-7721-E1A group was significantly higher than that of SMMC-7721group (P<0.01).The ratio of S stage in cell cycle of SMMC-7721-E1A was significantly lower than that in SMMC-7721 cell. The ratio of G2/M stage in cell cycle of SMMC-7721-E1A was significantly higher than that in SMMC-7721 cell (P<0.01).

Conclusion:

PEI could transfect E1A gene into hepatic carcinoma cells PEI-mediated E1A could effectively enhance radiosensitivity of hepatic carcinoma cells which may be related to its effects on apoptosis promoting leading to S phase suppression and G2/M phase arrest.