Telomerase Inhibition by MST-312 Sensitizes Breast Cancer Cells to the Anti-cancer Properties of Plumbagin.

Breast cancer is the most common cause of malignancy and the second most common cause of death due to cancer in women. This heterogeneous disease is currently broadly classified as estrogen receptor (ER), progesterone receptor (PR) positive luminal tumors, human epidermal growth factor receptor 2 (HER2) amplified tumors and triple-negative breast cancers (TNBC). Phytochemicals are proven to be promising anti-cancer chemotherapeutics agents with minimal cytotoxic effects on normal cells. Plumbagin (5-hydroxy-2-methyl-1, 4-naphthoquinone) is a phytochemical derived from the roots of Plumbago zeylanica and it is known to possess anti-cancer properties similar to other compounds of naphthoquinones. In about 90% of cancer cells, the telomerase enzyme activity is revived to add telomeric repeats to evade apoptosis. In this study, a combinatorial approach of combining the anti-cancer compound plumbagin to induce genotoxicity and a potent telomerase inhibitor, MST-312 (synthetic derivative of tea catechins), was used to determine the combinational treatment-induced lethality in breast cancer cells such as MDA-MB-231 (TNBC) and MCF-7 (lumina) cells. MDA-MB-231 cells were responsive to combination treatment in both short-term (48 h) and long-term treatment (14 days) in a synergistic manner, whereas in MCF-7, the combination treatment was more effective in the long-term regimen. Furthermore, the cytotoxic effects of the plumbagin and MST-312 combination treatment were not recoverable after the short-term treatment. In conclusion, a combination treatment of MST-312 and plumbagin is proven to be more effective than a single plumbagin compound treatment in inducing DNA damage and telomere dysfunction leading to greater genome instability, cell cycle arrest and eventually cell death in cancer cells.

Cross-sectional study of fetal long-bone length in an Iranian population at 17-25 weeks of gestation.

OBJECTIVE: To construct improved reference charts for fetal long bones in an Iranian setting and to compare them with previous studies. METHODS: The present prospective cross-sectional study included singleton fetuses assessed by ultrasonography at 17-25 weeks of gestation at the Comprehensive Medical Genetics Center, Shahid Soltani, Shiraz, Iran between May 1, 2012, and February 28, 2014. Exclusion criteria included conditions that could affect fetal growth. Fetal long bones (femur, humerus, tibia, fibula, ulna, and radius) were measured with ultrasonography and biometric charts were produced. Regression models were fitted to estimate bone lengths. The models produced were compared with those from previous studies in other populations. RESULTS: There were 660 singleton fetuses included and 660 femur, 633 humerus, 512 tibia, 498 fibula, 505 ulna, and 498 radius biometric measurements were recorded. The models generated to predict the length of the tibia, fibula, ulna, and radius from the length of the femur and humerus demonstrated a high goodness of fit when the predicted lengths were plotted against the actual lengths. Comparisons of mean lengths with previous studies suggested that long-bone length was affected by maternal ethnicity. CONCLUSION: The equations generated could be used to predict long-bone length in an Iranian population and ethnicity should be considered when using fetal long-bone length as a prenatal diagnostic tool.

Evaluation of bone marrow derived mesenchymal stem cells for full-thickness wound healing in comparison to tissue engineered chitosan scaffold in rabbit.

BACKGROUND: Chronic wounds present a major challenge in modern medicine. Even under optimal conditions, the healing process may lead to scarring and fibrosis. The ability of mesenchymal stem cells (MSCs) to differentiate into other cell types makes these cells an attractive therapeutic tool for cell transplantation. Both tissue-engineered construct and MSC therapy are among the current wound healing procedures and potential care. Chitosan has been widely applied in tissue engineering because of its biocompatibility and biodegradability. AIM: The aim of the current work was to compare the efficiency of MSCs and chitosan dressing, alone or in combination treatment on wound healing. METHODS: This study was conducted on 15 rabbits, which were randomly divided in 3 groups based on the type of treatment with MSCs, chitosan dressing and combination of both. A full-thickness skin defect was excised from the right and left side of the back of each animals. Defects on right sides were filled with treatments and left side defects were left as control. Evaluation of the therapeutic effectiveness was performed through a variety of clinical and microscopical evaluations and measurements of the process of wound healing on days 7, 14, 21, and 28. Histological evaluation of wound healing was classified by different scoring systems. RESULTS: The data indicated that wounds treated with bone marrow derived MSC had enhanced cellularity and better epidermal regeneration. During the early stages of wound healing, the closure rate of bone marrow derived MSC-treated wounds were significantly higher than other treatments (P<0.05). Although the MSCs in the wound edges enhance the healing of the full-thickness wound, the healing process of chitosan treatment was slower than the control group. CONCLUSION: This study revealed advanced granulation tissue formation and epithelialization in wounds treated with MSCs, and may suggests this treatment as an effective applicant in wound healing process. Chitosan scaffold dressings, whether alone or in combination with MSCs, have worsened the wound healing as compared to the control group.

Plumbagin triggers DNA damage response, telomere dysfunction and genome instability of human breast cancer cells.

AIM: Natural plant products are increasingly being used in cancer therapeutic studies due to their reduced normal cell toxicity. In this study, the anti-cancer properties of plumbagin, a naphthoquinone derivative extracted from the roots of Plumbago, were evaluated in breast cancer cells. METHODS: To evaluate the effects of plumbagin on breast cancer cell types, we employed a variety of techniques comprising cell viability, cell cycle assay, comet assay, western blotting, immunocytochemistry, measurement of telomerase activity, telomere restriction fragment length, quantitative fluorescence in situ hybridisation, along with gene expression analysis of untreated cells. RESULTS: Plumbagin treatment induced cytotoxicity in human breast cancer cells along with cell cycle arrest, DNA damage and cell death leading to apoptosis. Plumbagin was also found to suppress the telomerase activity in cancer cells accompanied by telomere attrition. Telomere shortening was corroborated by reduced telomere fluorescence on chromosome ends and genome instability. CONCLUSION: Together, these findings may suggest the application of plumbagin as adjuvant modality in breast cancer therapeutics.

Plumbagin alters telomere dynamics, induces DNA damage and cell death in human brain tumour cells.

Natural plant products may possess much potential in palliative therapy and supportive strategies of current cancer treatments with lesser cytotoxicity to normal cells compared to conventional chemotherapy. In the current study, anti-cancer properties of plumbagin, a plant-derived naphthoquinone, on brain cancer cells were determined. Plumbagin treatment resulted in the induction of DNA damage, cell cycle arrest and apoptosis, followed by suppression of the colony forming ability of the brain tumour cells. These effects were substantiated by upregulation of PTEN, TNFRSF1A and downregulation of E2F1 genes, along with a drop in MDM2, cyclin B1, survivin and BCL2 protein expression. Plumbagin induced elevated levels of caspase-3/7 activity as well. For the first time, we show here that plumbagin inhibits telomerase in brain tumour cells and results in telomere shortening following chronic long-term treatment. This observation implies considerable cytotoxicity of plumbagin towards cancer cells with higher telomerase activity. Collectively, our findings suggest plumbagin as a potential chemotherapeutic phytochemical in brain tumour treatment modalities.

Genetic variation in TGF-beta 1 gene promoter and risk of gestational trophoblastic disease.

OBJECTIVE: To examine the relationship of transforming growth factor beta 1 (TGF-beta 1) gene polymorphisms at promoter positions -509 (C/T) and -800 (G/A) with the risk of gestational trophoblastic disease (GTD) as compared to normal controls STUDY DESIGN: Polymerase chain reaction-restriction fragment length polymorphism was performed on peripheral blood of 102 patients with GTD and 124 normal, healthy, pregnant women as the control group. RESULTS: In this study, TGF-beta 1 gene polymorphisms at positions -509 (C/T) and -800 (G/A) failed to correlate with GTD. CONCLUSION: Our findings suggest that promoter gene polymorphisms of TGF-beta 1 do not play major roles in GTD and may not be risk factors for this disease.

Interleukin13 haplotypes and susceptibility of Iranian women to breast cancer.

Interleukin-13 (IL-13) is a TH2 cytokine with direct and indirect immunoregulatory functions on cancer cells. The cytokine has been reported to have some polymorphic variations at the gene level associated with some immune related diseases including asthma and allergy. In the present study, association of three IL13 gene polymorphisms at positions -1512 A/C and -1055 C/T in the promoter and +2044 G/A in exon-4 was investigated in Iranian women with breast cancer and healthy controls. Genotyping of IL13 gene polymorphisms were performed by PCR-RFLP methods. Serum level of IL-13 was assessed by ELISA. Haplotypes were constructed from genotypic data using Arlequin 3.1 software package. Haplotype analysis revealed higher frequency of a three-locus haplotype, ACA (-1512A/-1055C/+2044A), in normal women than breast cancer patients (P < 0.025). Haplotype CCA, from the other hand, was observed with more frequency among patients than controls (P < 0.03). No statistically significant differences were found in the frequency of genotypes and alleles between patients and control group. No association was observed between investigated genotypes and other prognostic factors including tumor type, lymph node involvement and tumor size. IL-13 serum level was undetectable in both patients and control subjects. Despite observing no association between breast cancer and the single SNPs, results of this investigation suggest that the presence of CCA haplotype of IL13 gene may be associated with susceptibility of Iranian women to breast cancer.

Lack of association between interleukin-13 gene polymorphisms (-1055 C/T and +2044 G/A) in Iranian patients with lung cancer.

Lung cancer is one of the leading causes of death from cancer. Both immune cells and tumor cells play a key role in lung cancer immunity by secretion of cytokines and developing type-2 cell-mediated immune response. IL-13 is an immunoregulatory cytokine affecting tumor immunosurveillance by deviation of immune response from Th1 to Th2. In the present study we sought to determine the association of single nucleotide polymorphisms (SNPs) of IL-13 gene at positions +2044 (G/A) and -1055 (C/T) and lung cancer. One hundred forty one patients and 113 controls were recruited; control group was subdivided into smoker and nonsmoker individuals for serum detection. Genotyping was carried out by PCR-RFLP assay and IL-13 detection by ELISA method. No statistically significant difference was found in the frequency of genotypes, alleles, and haplotypes at positions +2044 (G/A) and -1055 (C/T) of IL-13 gene between lung cancer patients and controls. Serum level of IL-13 was not detectable in both groups. The results of this study reveal that although +2044 (G/A) and -1055 (C/T) SNPs in IL-13 are implicated in some pulmonary processes, they do not confer susceptibility to lung cancer in Iranian population.