The relationship between anticancer effect of metformin and the transcriptional regulation of certain genes (CHOP, CAV-1, HO-1, SGK-1 and Par-4) on MCF-7 cell line

BACKGROUND

1,1-dimethylbiguanide hydrochloride (biguanide metformin) is a hypoglycemic agent that is widely used in the treatment of Type 2 diabetes. Use of metformin was found to be associated with the lower risk of cancer. It is suggested that metformin has an anticancer and antiproliferative effect and affects the apoptosis by activating the AMPK and inhibiting the mammalian target of rapamycin (mTOR). Although the effects of metformin treatment of various types of cancers are defined with many mechanisms, the literature provides only sufficient information about how it affects the SGK-1, Par-4 and Cav-1 mRNA expressions and the impact of this effect on cytotoxicity. The breast cancer is globally one of the most important causes of cancer-related mortality for women. We, therefore investigated the possible effects of metmorfin on proliferation, cytotoxicity and some unfolded protein response (UPR) genes in the breast cancer cells (MCF-7).

MATERIALS AND METHODS

We administrated 0.31 mM, 2.5 mM and 10 mM of metformin alone and in combination with 2-DG to the MCF-7 cells and monitored the cell viability and proliferation with real-time cell analyzer system for 48 hours. We also measured CHOP, Cav-1, HO-1, SGK-1 and Par-4 genes mRNA expression levels using Real Time-Polymerase Chain Reaction (RT-PCR). We considered the GAPDH gene as reference gene and the control groups as calibrator. We performed an analysis for relative gene expressions of the study groups.

RESULTS

Metformin caused transcriptional regulation of UPR and tumor-related genes in MCF-7 cells and inhibited the proliferation depending on the dose, resulting in cytotoxic effect.

CONCLUSIONS

We consider that administration of metformin with chemotherapeutic agents could be an effective method in treatment of breast cancer through mechanisms such as reduced resistance to chemotherapy and increased cytotoxic activity.

Amitriptyline overdose in emergency department of university hospital: evaluation of 250 patients

OBJECTIVE

The purpose of this study was to evaluate the patients with acute amitriptyline poisoning and investigate predictive factors for the development of life-threatening complications.

METHODS

Demographics, clinical, laboratory, and electrocardiographic (ECG) findings of 250 patients were evaluated retrospectively. Predictive parameters for the development of serious complications were studied.

RESULTS

Median age of patients was 14.6 years, of which, 70% of patients were female and 66% were in pediatric age group. The most common pathological clinical finding and laboratory abnormality were alteration of consciousness and hyponatremia. The rate of convulsive seizure, arrhythmia, and respiratory depression were 17 (6.8%), 16 (6.4%), and 11 (4.4%), respectively. These complications were more seen in pediatric patients than adults (15.8% and 1.2%). The incidence of hyponatremia was more in pediatric patients and severe poisoning groups (38.8 and 53.4%, respectively). The levels of amitriptyline and nortriptyline were significantly higher in the group with complications than the group without complications (p < 0.05). All adult patients were discharged with good prognosis. In pediatric age group, one patient was discharged with severe neurological sequelae and one patient died. QRS duration >100 ms, long corrected QT duration interval, and low Glasgow Coma Score (GCS) at admission were identified as independent risk factors for the development of life-threatening complications (odds ratio: 69.4, 1.9, and 1383, respectively; p < 0.05).

CONCLUSION

Amitriptyline poisoning may be associated with life-threatening complications, especially in pediatric age group and in patients with hyponatremia. Low GCS, presence of hyponatremia, high serum drug levels, and pathological ECG findings on admission may be helpful in predicting the development of complications and poor prognosis.