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BackgroundObesity has been associated with increased mortality from hormone dependant cancers such as breast cancer which is the most prevalent cancer in women. The link between obesity and breast cancer can be attributed to excess estrogen produced through aromatization in adipose tissue. The role of steroid hormone receptors in breast cancer development is well studied but how obesity can affect the expression pattern of steroid hormones in patients with different grades of breast cancer was the aim of this study.MethodsIn this case-control study, 70 women with breast cancer participated with different grades of obesity (36 none obese, BMI < 25 kg/m2 and 34 obese, BMI ≥ 25 kg/m2). The mean age of participants was 44.53 ± 1.79 yr (21–70 yr). The serum level of estrogen, progesterone and androgen determined by ELISA. Following quantitative expression of steroid hormone receptors mRNA in tumor tissues evaluated by Real-time PCR. Patients with previous history of radiotherapy or chemotherapy were excluded. SPSS 16 was used for data analysis and P < 0.05 considered statistically significant.ResultsThe difference in ERα, ERβ and PR mRNA level between normal and obese patients was significant (P < 0.001). In addition, the expression of AR mRNA was found to be higher than other steroid receptors. There was no significant relation between ERβ gene expression in two groups (P = 0.68). We observed a significant relationship between ERα and AR mRNA with tumor stage and tumor grade, respectively (P = 0.023, P = 0.015).ConclusionAccording to the obtained results, it is speculated that obesity could paly a significant role in estrogen receptors gene expression and also could affect progression and proliferation of breast cancer cells.

Background: Despite numerous useful anticancer properties of curcumin, its utility is limited due to its hydrophobic structure. In this study, we investigated the comparative antiproliferative effect of PAMAM encapsulating curcumin with naked curcumin on the T47D breast cancer cell line. Materials and Methods: Cytotoxic effects of PAMAM dendrimers encapsulating curcumin and curcumin alone were investigated by MTT assay. After treating cells with different concentrations of both curcumin alone and curcumin encapsulated for 24h, telomerase activity was determined by TRAP assay. Results: While PAMAM dendrimers encapsulating curcumin had no cytotoxicity on cancer cells, they decreased the IC 50 for proliferation and also increased the inhibitory effect on telomerase activity. Conclusions: Considering the non-toxicity in addition to effectiveness for enhancing curcumin anticancer properties, dendrimers could be considered good therapeutic vehicles for this hydrophobic agent.

Telomerase is a ribonucleoprotein enzyme, which has a significant role in synthesizing DNA telomeric in eukaryotes. Telomere maintenance can cause to immortalization and malignant transformation of human cells and thereby telomerase activity must be scrutinized as an important factor in most tumor cells. The proliferation of cancer cells or apoptosis induction can be suppressed by telomerase inhibition using different therapeutic agents without any side effects upon normal cells. Natural substances, with anti-tumor effects, such as those derived from plants can be suitable candidates due to their capabilities in preventing some side effects and resistance of tumors with respect to most chemotherapeutic drugs. In this regards, many studies have shown that natural phytochemicals have inhibitory effects on telomerase activity through affecting its subunits and components. Therefore, the aim of this paper is to review the recent studies on these kinds of phytochemicals in terms of property and mechanism. Moreover, strategies for improving the therapeutic efficacy of plant-derived substances such as combination therapy and nanoformulation based approaches are included.

Leptin plays the role of mitogenic factor in the breast carcinogenesis. Therefore, it could be considered as a target for breast cancer therapy. Leptin gene expression could be modulated by activation of estrogen receptors. Silibinin is an herbal compound with anti-cancer activity on prostate and colorectal cancers. Based on the fact that targeting of leptin can be considered as a novel strategy for breast cancer therapy, the aim of this study was the investigation of potentiality of silibinin for inhibition of leptin gene expression and secretion, and its link with expression of estrogen receptors. Cytotoxic effect of silibinin on T47D breast cancer cells was investigated by MTT assay test after 24, 48 and 72 h treatments with different concentrations of silibinin. The levels of leptin, estrogen receptor α and estrogen receptor β genes expression was measured by reverse-transcription real-time PCR. The amount of secreted leptin in the culture medium was determined by ELISA. Data were statistically analyzed by one-way ANOVA test. Silibinin inhibits growth of T47D cells in a time and dose dependent manner. There was significant difference between control and treated cells in the levels of leptin, estrogen receptor β expression levels and the quantity of secreted leptin was decreased in the treated cells in comparison to control cells. In conclusion, silibinin inhibits the expression and the secretion of leptin and in the future it might probably be a drug candidate for breast cancer therapy through leptin targeting.

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The aim of this study was to investigate the effect of zinc oxide nanoparticles (ZnO‐NPs) on the expression of genes involved in toxin–antitoxin (TA) systems in multidrug‐resistant (MDR) Acinetobacter baumannii. Seventy clinical isolates of A. baumannii were collected from variuos clinical samples. Antimicrobial susceptibility test was determined by disk diffusion. Type II TA system‐related genes including GNAT, XRE‐like, hipA, hipB, hicA, hicB were screened using polymerase chain reaction (PCR). ZnO‐NPs prepared and characterized by field emission scanning electron microscopy and X‐ray diffraction. MIC of ZnO‐NPs of A. baumannii isolates was performed using the microdilution method. The expression of type II TA systems‐related genes were assessed with and without exposure to ZnO‐NPs using real‐time PCR. The highest rate of resistance and sensitivity was observed against cefepime (77.14%), and ampicillin/sulbactam (42.85%), respectively. All A. baumannii isolates were considered as MDR. In this study, three TA loci were identified for A. baumannii including GNAT/XRE‐like, HicA/HicB, and HipA/HipB and their prevalence was 100%, 42%, and 27.1%, respectively. There was no significant relationship between the prevalence of these systems and the origin of A. baumannii. Our data showed significant correlations between the presence of HicA/HicB system and resistance to ceftazidime, meropenem, imipenem, and cefepime (p < 0.05), and the presence of HipA/HipB system and resistance to ceftazidime, meropenem, imipenem, and cefepime (p < 0.05). In presence of ZnO‐NPs, the expression of all studied genes decreased. GNAT and hicB showed the highest and lowest expression changes by 2.4 folds (p < 0.001) and 1.3 folds (p < 0.05), respectively. This study demonstrates the promising potential of nanoparticles to impact the expression of the genes involved in TA Systems. So, the application of ZnO‐NPs may be helpful to design target‐based strategies towards MDRs pathogens for empowered clinical applications by microbiologists and nanotechnologists.

BACKGROUND: A doctor–patient relationship built on the concept of empathy is so essential to attain the best clinical outcomes in medicine. Since empathy has a positive role in interpersonal relationships and medical outcomes, its assessment is highly crucial. The aim of this study was to assess the empathy in last-year medical students using the Persian version of the Jefferson Scale of Physician Empathy (JSPE) and correlate empathy scores with demographic features. MATERIALS AND METHODS: In this cross-sectional study, last-year medical students at Shiraz Medical School, Shiraz, Iran, were recruited for this study. In this research, we used the Persian version of JSPE. The validity and reliability of the Persian version of this tool were confirmed in the previous research. For the analysis of data, we employed descriptive statistics and the independent sample t -test. RESULTS: One hundred and eighty-five final-year medical students were included in this study. The maximum score of the questionnaire was 140, and the total mean score of empathy was 98.15 ± 13.29. The females' total mean score (102.05 ± 11.89) was higher than the males' score (93.57 ± 13.46). The difference between the mean score of gender and empathy was significant ( P value <.001), but there was no significant difference between empathy and the two other demographic factors ( P > 0.05). CONCLUSIONS: Although physicians would gain the essential characteristics of empathy during their career, attending professors and other responsible policymakers in medical education should focus more on the factors related to physicians' empathy to train better and more professional physicians.