Telomeric DNA induces apoptosis and senescence of human breast carcinoma cells

INTRODUCTION: Cancer is a leading cause of death in Americans. We have identified an inducible cancer avoidance mechanism in cells that reduces mutation rate, reduces and delays carcinogenesis after carcinogen exposure, and induces apoptosis and/or senescence of already transformed cells by simultaneously activating multiple overlapping and redundant DNA damage response pathways. METHODS: The human breast carcinoma cell line MCF-7, the adriamycin-resistant MCF-7 (Adr/MCF-7) cell line, as well as normal human mammary epithelial (NME) cells were treated with DNA oligonucleotides homologous to the telomere 3' overhang (T-oligos). SCID mice received intravenous injections of MCF-7 cells followed by intravenous administration of T-oligos. RESULTS: Acting through ataxia telangiectasia mutated (ATM) and its downstream effectors, T-oligos induced apoptosis and senescence of MCF-7 cells but not NME cells, in which these signaling pathways were induced to a far lesser extent. In MCF-7 cells, experimental telomere loop disruption caused identical responses, consistent with the hypothesis that T-oligos act by mimicking telomere overhang exposure. In vivo, T-oligos greatly prolonged survival of SCID mice following intravenous injection of human breast carcinoma cells. CONCLUSION: By inducing DNA damage-like responses in MCF-7 cells, T-oligos provide insight into innate cancer avoidance mechanisms and may offer a novel approach to treatment of breast cancer and other malignancies

Anastrozole versus tamoxifen for the prevention of locoregional and contralateral breast cancer in postmenopausal women with locally excised ductal carcinoma in situ (IBIS-II DCIS): a double-blind, randomised controlled trial

Background Third-generation aromatase inhibitors are more effective than tamoxifen for preventing recurrence in postmenopausal women with hormone-receptor-positive invasive breast cancer. However, it is not known whether anastrozole is more effective than tamoxifen for women with hormone-receptor-positive ductal carcinoma in situ (DCIS). Here, we compare the efficacy of anastrozole with that of tamoxifen in postmenopausal women with hormone-receptor-positive DCIS. Methods In a double-blind, multicentre, randomised placebo-controlled trial, we recruited women who had been diagnosed with locally excised, hormone-receptor-positive DCIS. Eligible women were randomly assigned in a 1:1 ratio by central computer allocation to receive 1 mg oral anastrozole or 20 mg oral tamoxifen every day for 5 years. Randomisation was stratified by major centre or hub and was done in blocks (six, eight, or ten). All trial personnel, participants, and clinicians were masked to treatment allocation and only the trial statistician had access to treatment allocation. The primary endpoint was all recurrence, including recurrent DCIS and new contralateral tumours. All analyses were done on a modified intention-to-treat basis (in all women who were randomised and did not revoke consent for their data to be included) and proportional hazard models were used to compute hazard ratios and corresponding confidence intervals. This trial is registered at the ISRCTN registry, number ISRCTN37546358. Results Between March 3, 2003, and Feb 8, 2012, we enrolled 2980 postmenopausal women from 236 centres in 14 countries and randomly assigned them to receive anastrozole (1449 analysed) or tamoxifen (1489 analysed). Median follow-up was 7·2 years (IQR 5·6–8·9), and 144 breast cancer recurrences were recorded. We noted no statistically significant difference in overall recurrence (67 recurrences for anastrozole vs 77 for tamoxifen; HR 0·89 [95% CI 0·64–1·23]). The non-inferiority of anastrozole was established (upper 95% CI <1·25), but its superiority to tamoxifen was not (p=0·49). A total of 69 deaths were recorded (33 for anastrozole vs 36 for tamoxifen; HR 0·93 [95% CI 0·58–1·50], p=0·78), and no specific cause was more common in one group than the other. The number of women reporting any adverse event was similar between anastrozole (1323 women, 91%) and tamoxifen (1379 women, 93%); the side-effect profiles of the two drugs differed, with more fractures, musculoskeletal events, hypercholesterolaemia, and strokes with anastrozole and more muscle spasm, gynaecological cancers and symptoms, vasomotor symptoms, and deep vein thromboses with tamoxifen. Conclusions No clear efficacy differences were seen between the two treatments. Anastrozole offers another treatment option for postmenopausal women with hormone-receptor-positive DCIS, which may be be more appropriate for some women with contraindications for tamoxifen. Longer follow-up will be necessary to fully evaluate treatment differences

Spectral domain optical coherence tomography findings in patients with acute syphilitic posterior placoid chorioretinopathy

PURPOSE: To describe the appearance of acute syphilitic posterior placoid chorioretinitis, a rare ocular manifestation of syphilis, on spectral domain optical coherence tomography (SD OCT) both before and after treatment. METHODS: Ophthalmic examination and imaging studies of 30 eyes of 19 confirmed cases were analyzed both at the time of presentation and at each follow-up visit. Patients with SD OCT and fluorescein angiography at the time of presentation, and at least three documented follow-up visits after initiation of therapy, were included in the study. Standard treatment of neurosyphilis was given to each patient, including 4 million units of penicillin G administered intravenously every 4 hours for 14 days. RESULTS: Fundus examination and imaging studies were consistent with previous reports and confirmed the diagnosis of acute syphilitic posterior placoid chorioretinitis. In 13 eyes (43.3%), baseline SD OCT scans were performed within 1 to 2 days of presentation and revealed a small amount of subretinal fluid, disruption of the inner segment/outer segment junction, and hyperreflective thickening of the retinal pigment epithelium (RPE). All 30 eyes were again scanned between Days 7 and 9 after presentation and revealed loss of the inner segment/outer segment and OS/RPE bands, and irregular hyperreflectivity of the RPE with prominent nodular elevations but without subretinal fluid. Early disruption of the external limiting membrane and punctate choroidal hyperreflectivity were seen in 1 of the 30 eyes (3.3%) and 14 of the 30 eyes (46.6%), respectively. Vision improved and the outer retinal abnormalities normalized in 28 of the 30 eyes (93.3%) after the treatment of neurosyphilis. The external limiting membrane, inner segment/outer segment band, and/or linear outer segment/RPE junction remained substantially abnormal despite treatment in 2 eyes left with 20/200 vision. CONCLUSION: Patients with acute syphilitic posterior placoid chorioretinitis show characteristic outer retinal abnormalities on SD OCT imaging, including disruption of the inner segment/outer segment band, nodular thickening of the RPE with loss of the linear outer segment/RPE junction, and, in some cases, loss of the external limiting membrane, accumulation of subretinal fluid, and punctate hyperreflectivity in the choroid. Vision improved and these abnormalities reversed after treatment of neurosyphilis in most of the patients. Persistently, poor vision despite treatment was associated with long-term loss or disruption of outer retinal anatomy on SD OCT. Copyright © by Ophthalmic Communications Society, Inc

Spectral domain optical coherence tomography findings in patients with acute syphilitic posterior placoid chorioretinopathy.

PURPOSE: To describe the appearance of acute syphilitic posterior placoid chorioretinitis, a rare ocular manifestation of syphilis, on spectral domain optical coherence tomography (SD OCT) both before and after treatment. METHODS: Ophthalmic examination and imaging studies of 30 eyes of 19 confirmed cases were analyzed both at the time of presentation and at each follow-up visit. Patients with SD OCT and fluorescein angiography at the time of presentation, and at least three documented follow-up visits after initiation of therapy, were included in the study. Standard treatment of neurosyphilis was given to each patient, including 4 million units of penicillin G administered intravenously every 4 hours for 14 days. RESULTS: Fundus examination and imaging studies were consistent with previous reports and confirmed the diagnosis of acute syphilitic posterior placoid chorioretinitis. In 13 eyes (43.3%), baseline SD OCT scans were performed within 1 to 2 days of presentation and revealed a small amount of subretinal fluid, disruption of the inner segment/outer segment junction, and hyperreflective thickening of the retinal pigment epithelium (RPE). All 30 eyes were again scanned between Days 7 and 9 after presentation and revealed loss of the inner segment/outer segment and OS/RPE bands, and irregular hyperreflectivity of the RPE with prominent nodular elevations but without subretinal fluid. Early disruption of the external limiting membrane and punctate choroidal hyperreflectivity were seen in 1 of the 30 eyes (3.3%) and 14 of the 30 eyes (46.6%), respectively. Vision improved and the outer retinal abnormalities normalized in 28 of the 30 eyes (93.3%) after the treatment of neurosyphilis. The external limiting membrane, inner segment/outer segment band, and/or linear outer segment/RPE junction remained substantially abnormal despite treatment in 2 eyes left with 20/200 vision. CONCLUSION: Patients with acute syphilitic posterior placoid chorioretinitis show characteristic outer retinal abnormalities on SD OCT imaging, including disruption of the inner segment/outer segment band, nodular thickening of the RPE with loss of the linear outer segment/RPE junction, and, in some cases, loss of the external limiting membrane, accumulation of subretinal fluid, and punctate hyperreflectivity in the choroid. Vision improved and these abnormalities reversed after treatment of neurosyphilis in most of the patients. Persistently, poor vision despite treatment was associated with long-term loss or disruption of outer retinal anatomy on SD OCT

Donor methylenetetrahydrofolate reductase genotype is associated with graft-versus-host disease in hematopoietic stem cell transplant patients treated with methotrexate

Methotrexate (MTX), used as a graft-versus-host disease (GvHD) prophylactic agent in hematopoietic stem cell transplantation (HSCT), exerts its effect via folate cycle inhibition. A critical enzyme involved in folate metabolism is 5,10-methylenetetrahydrofolate reductase (MTHFR). We examined the association of a single nucleotide polymorphism (SNP) at position 677 in the MTHFR gene on GvHD outcomes in allogeneic HSCT patients administered MTX. MTHFR genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) on 193 HSCT patients and donors. A total of 140 patients were transplanted with an HLA-matched related donor and 53 with an unrelated donor. GvHD outcomes were compared between genotypes by univariate and multivariate analysis. The combined donor 677CT and TT genotypes were associated with a decreased incidence of GvHD (acute and chronic combined) in HSCT recipients with an HLA-matched related donor (75% at 1 year in the CT and TT group compared with 91% in the wild type CC group, P=0.01), increased time to onset of first GvHD (P=0.001) and time to first GvHD treated with systemic therapy (P=0.022). Unrelated donor MTHFR genotype was not associated with outcome parameters and no associations of recipient genotype in either related or unrelated donor cohorts were observed

Bases biomoleculares do fotoenvelhecimento Molecular basis of photoaging

Com o aumento da expectativa de vida, o estudo do processo de envelhecimento orgânico tem sido estimulado. O envelhecimento da pele, órgão que espelha os sinais do tempo, é processo de deterioração progressiva, tempo-dependente, e pode ser intensificado pela exposição solar, então designado fotoenvelhecimento. O dano das radiações sobre diversas estruturas celulares e cutâneas leva a alterações morfológicas nesses componentes, fruto de modificações biomoleculares. Muitas pesquisas são desenvolvidas com o intuito de combater ou minimizar os efeitos do fotoenvelhecimento, porém a principal estratégia nesse sentido continua sendo a prevenção, só conseguida pelo progressivo desvendar dos mecanismos fisiopatogênicos envolvidos nesse processo.<br>As a result of the increase in life expectancy, the study of the organic process of aging has been stimulated. Skin ageing, which reflects the signs of time, is a time-dependent process of progressive deterioration that can be intensified by sun exposure, which is known as photoaging. The damage of radiation on various cell structures and on the skin results in molecular and morphological changes to these components. Many research studies are performed to try to minimize the effects of photoaging; however, the main strategy to manage it is still prevention, which will only be achieved once we learn about the mechanisms involved in the process