The effect of elemene on lung adenocarcinoma A549 cell radiosensitivity and elucidation of its mechanism

OBJECTIVE: To investigate the effect of elemene on the radiosensitivity of A549 cells and its possible molecular mechanism. METHODS: Apoptosis of A549 cells was detected by flow cytometry and fluorescence microscopy. The effect of double-strand break (DSB) damage repair in A549 cells was evaluated using the neutral comet assay. Protein expression levels were detected using western blotting, and the correlation between protein levels was analyzed. RESULTS: Elemene exhibited a radiosensitizing effect on A549 cells. The level of apoptosis induced by elemene combined with radiation was significantly greater (p<0.01) than that elicited by either radiation or elemene alone. Following radiation and subsequent repair for 24 h, the tail intensity of A549 cells treated with a combination of elemene and radiation was greater than that of cells treated with either elemene or radiation alone (p<0.01). This result indicates that elemene inhibits cellular DSB repair. Both elemene combined with radiation and radiation alone decreased the protein expression of DNA-PKcs and Bcl-2 compared to elemene alone (p<0.01), while p53 protein expression was increased (p<0.01). A negative correlation was observed between DNA-PKcs and p53 expression (r=−0.569, p=0.040), while a positive correlation was found between DNA-PKcs and Bcl-2 expression (r=0.755, p=0.012). CONCLUSIONS: Elemene exhibits a radiosensitizing effect on A549 cells, and its underlying molecular mechanism of action may be related to the downregulation of DNA-PKcs gene expression. .

MicroRNAs, cancer and ionizing radiation: Where are we? / MicroRNAs, câncer e radiação ionizante: em que ponto estamos?

Summary The aim of this study is to describe the biogenesis of microRNA, its relations with carcinogenesis, and the correlation between microRNA and ionizing radiation (IR), focusing on radioresponsiveness. It is known that microRNA biogenesis is well established and involves different enzymatic cleavages, resulting in the production of mature microRNA. MicroRNAs are involved in carcinogenesis. Their interaction is related to the genetic and epigenetic changes associated with activation of proto-oncogenes or inactivation of tumor suppressor genes. Several studies have shown that the levels of expression of some microRNAs vary significantly after irradiation. There are evidences that microRNAs can influence cellular response after IR. In addition, microRNAs are related to modulation of the expression of several post-transcriptional targets in DNA damage response pathways, and to the DNA damage repair regulation mechanism. Future studies can clarify a possible clinical use of microRNAs as a new class of radiosensitive agents.

Resumo O objetivo do presente estudo é descrever a biogênese do microRNA, suas relações na carcinogênese e a correlação do microRNA com a radiação ionizante (RI), com enfoque na radiorresponsividade. Observou-se que a biogênese do microRNA está bem estabelecida e envolve diversas clivagens enzimáticas que resultam na produção do microRNA maduro. Os microRNAs estão envolvidos na carcinogênese. Sua interação está relacionada às alterações genéticas e epigenéticas, associadas à ativação de proto- -oncogenes ou à inativação de genes supressores de tumor. Vários estudos demonstraram que os níveis de expressão de alguns microRNAs variam significativamente após a irradiação. Há evidências de que os microRNAs podem influenciar a resposta celular após a RI. Além disso, os microRNAs estão relacionados à modulação da expressão de vários alvos de pós-transcrição das vias de resposta aos danos no DNA e o do mecanismo de regulação de reparação de danos do DNA. Estudos futuros podem elucidar uma possível utilização clínica dos microRNAs como uma nova classe de agentes radiossensíveis.

Does hypericin boost the efficacy of high-power laser? A preliminary experimental study on rats / A hipericina aumenta a eficácia do laser de alta potência? Um estudo preliminar e experimental em ratos

CONTEXT AND OBJECTIVE: Lasers are widely used in treating symptomatic benign prostatic hyperplasia. In current practice, potassium titanyl phosphate (KTP) lasers are the most common type of laser systems used. The aim here was to evaluate the rapid effect of high-power laser systems after application of hypericin. DESIGN AND SETTING: Experimental animal study conducted in the Department of Urology, Gülhane Military Medical Academy, Ankara, Turkey, in 2012. METHODS: Sixteen rats were randomized into four groups: 120 W KTP laser + hypericin; 120 W KTP laser alone; 80 W KTP laser + hypericin; and 80 W KTP laser alone. Hypericin was given intraperitoneally two hours prior to laser applications. The laser incisions were made through the quadriceps muscle of the rats. The depth and the width of the laser incisions were evaluated histologically and recorded. RESULTS: To standardize the effects of the laser, we used the ratio of depth to width. These new values showed us the depth of the laser application per unit width. The new values acquired were evaluated statistically. Mean depth/width values were 231.6, 173.6, 214.1 and 178.9 in groups 1, 2, 3 and 4, respectively. The most notable result was that higher degrees of tissue penetration were achieved in the groups with hypericin (P < 0.05). CONCLUSIONS: The encouraging results from our preliminary study demonstrated that hypericin may improve the effects of KTP laser applications. .

CONTEXTO E OBJETIVO: Lasers são amplamente utilizados no tratamento de hiperplasia benigna de próstata sintomática. Na prática atual, lasers de fosfato de titanilo de potássio (KTP) são os tipos mais comuns usados dos sistemas. O objetivo foi avaliar o efeito rápido do sistema laser de alta potência após a aplicação de hipericina. TIPO DE ESTUDO E LOCAL: Estudo experimental animal, realizado no Departamento de Urologia, Academia de Medicina Militar de Gülhane, Ancara, Turquia, em 2012. MÉTODOS: 16 ratos foram divididos aleatoriamente em 4 grupos: 120W KTP laser + hipericina; 120W KTP laser somente; 80W KTP laser + hipericina; 80W KTP laser somente. Hipericina foi dada intraperitonealmente duas horas antes da aplicação do laser. As incisões a laser foram feitas através do músculo quadríceps dos ratos. A profundidade e a largura das incisões a laser foram avaliadas histologicamente e registradas. RESULTADOS: Para padronizar o efeito do laser foi utilizada a razão entre profundidade e largura. Estes novos valores nos mostraram a profundidade da aplicação do laser de largura por unidade. Os novos valores adquiridos foram avaliados estatisticamente. Os valores da média de profundidade/largura foram 231,6, 173,6, 214,1 e 178,9 nos grupos 1, 2, 3 e 4, respectivamente. O resultado mais notável foi atingir altos graus de penetração tecidual nos grupos com hipericina (P < 0,05). CONCLUSÕES: Os resultados promissores do nosso estudo preliminar mostraram que hipericina pode melhorar os efeitos das aplicações do laser KTP. .

Protein microarray for complex apoptosis monitoring of dysplastic oral keratinocytes in experimental photodynamic therapy

BACKGROUND: Photodynamic therapy is an alternative treatment of muco-cutaneous tumors that uses a light source able to photoactivate a chemical compound that acts as a photosensitizer. The phthalocyanines append to a wide chemical class that encompasses a large range of compounds; out of them aluminium-substituted disulphonated phthalocyanine possesses a good photosensitizing potential. RESULTS: The destructive effects of PDT with aluminium-substituted disulphonated phthalocyanine are achieved by induction of apoptosis in tumoral cells as assessed by flow cytometry analysis. Using protein microarray we evaluate the possible molecular pathways by which photodynamic therapy activates apoptosis in dysplastic oral keratinocytes cells, leading to the tumoral cells destruction. Among assessed analytes, Bcl-2, P70S6K kinase, Raf-1 and Bad proteins represent the apoptosis related biomolecules that showed expression variations with the greatest amplitude. CONCLUSIONS: Up to date, the intimate molecular apoptotic mechanisms activated by photodynamic therapy with this type of phthalocyanine in dysplastic human oral keratinocytes are not completely elucidated. With protein microarray as high-throughput proteomic approach a better understanding of the manner in which photodynamic therapy leads to tumoral cell destruction can be obtained, by depicting apoptotic molecules that can be potentially triggered in future anti-tumoral therapies.

Particularização do adenocarcinoma do colo frente ao conhecimento atual / Particularization of cervix adenocarcinoma according to current knowledge

O adenocarcinoma do colo uterino (AC) está ficando cada vez mais frequente, passando, nas últimas décadas, de 15 para até 25% do total, tendendo a ocorrer mais em jovens, com uma evolução mais rápida. O rastreamento citológico é menos eficiente na detecção de alterações glandulares, devido à sua menor frequência e falta de padronização citopatológicas. A associação de testes de papilomavírus humano (HPV) acrescida de marcadores como p16 e Ki-67, poderá melhorar a sua detecção. Falta especificidade nas imagens colposcópicas e a investigação endocervical não está padronizada. O adenocarcinoma in situ (AIS) é de difícil diagnóstico, e é comum o AC ser detectado em estádios mais avançados. Mas uma vez tratado e controlado, este ainda apresenta um maior risco de metástases, quando comparado aos carcinomas escamosos no mesmo estádio. Não existe, até o momento, uma definição de tratamento de acordo com o tipo histológico. Nestes casos, estudos recentes começam a mostrar um potencial benefício da adição de quimioterapia com taxano antes e após o tratamento convencional do AC. Frente às dificuldades no manejo da neoplasia glandular cervical, há uma perspectiva de impacto positivo na diminuição dos AIS e AC decorrente da vacinação contra HPV de meninas e mulheres jovens, que necessitarão de novas estratégias de rastreamento.

The cervix adenocarcinoma (AC) is becoming more frequent, rising in recent decades from 15 to 25% of the total, tending to occur in younger and have a faster evolution. The cytological screening is less efficient in detecting glandular changes due to low frequency and lack of cytopathological standardization. The association of human papillomavirus (HPV) testing plus biomarkers as p16 and Ki-67 may improve the detection. There is a lack of the specificity in colposcopic images and the endocervical samples studies are not standardized. The adenocarcinoma in situ (AIS) is difficult to diagnose, and the AC is often detected in advanced stages. Once treated and controlled, the AC has a higher risk of metastases when compared to squamous carcinomas at the same stage. There is not yet a definition of treatment according to the histologic type. Recent studies have begun to show a potential benefit of the addition of taxane based chemotherapy to conventional treatment for AC. Faced with difficulties in the management of cervical glandular neoplasia, there is the perspective of positive impact in the reduction of AIS and AC resulting from HPV vaccination of girls and young women, that with lesser risks, they will require new screening algorithms.

Boron neutron capture therapy in cancer: past, present and future

Undifferentiated thyroid cancer (UTC) is a very aggressive tumor with no effective treatment, since it lacks iodine uptake and does not respond to radio or chemotherapy. The prognosis of these patients is bad, due to the rapid growth of the tumor and the early development of metastasis. Boron neutron capture therapy (BNCT) is based on the selective uptake of certain boron non-radioactive compounds by a tumor, and the subsequent irradiation of the area with an appropriate neutron beam. 10B is then activated to 11B, which will immediately decay releasing alpha particles and 7Li, of high linear energy transfer (LET) and limited reach. Clinical trials are being performed in patients with glioblastoma multiforme and melanoma. We have explored its possible application to UTC. Our results demonstrated that a cell line of human UTC has a selective uptake of borophenylalanine (BPA) both in vitro and after transplantation to nude mice. Treatment of mice by BNCT led to a complete control of growth and cure of 100 percent of the animals. Moreover dogs with spontaneous UTC also have a selective uptake of BPA. At the present we are studying the biodistribution of BPA in patients with UTC before its application in humans.

O câncer indiferenciado de tiróide (CIT) é um tumor muito agressivo sem tratamento efetivo, uma vez que não capta iodo e não responde à radio ou quimioterapia. O prognóstico desses pacientes é ruim, devido ao rápido crescimento do tumor e surgimento precoce de metástases. A terapia por captura de nêutrons de boro (TCNB) é baseada na captação seletiva de certos compostos de boro não-radioativos pelo tumor, e à subsequente irradiação da área com um feixe de nêutrons apropriado. O 10B é então ativado para 11B, cujo decaimento imediato libera partículas alfa e 7Li, de alta transferência linear de energia (TLE) e alcance limitado. Ensaios clínicos estão sendo conduzidos em pacientes com glioblastoma multiforme e melanoma, e nós estamos explorando sua possível aplicação no CIT. Nossos resultados demonstram que uma linhagem celular do CIT humano mostra captação seletiva de borofenilalanina (BPA) tanto in vitro como após transplante em camundongos "nude". O tratamento de camundongos com TCNB leva a um controle completo do crescimento tumoral e à cura em 100 por cento dos animais. Além disso, cães com CIT espontâneo também apresentam captação seletiva de BPA. No momento, estamos estudando a biodistribuição de BPA em pacientes com CIT, antes de sua aplicação em humanos.

Estudo fase I/II com capecitabina e radioterapia neoadjuvante em / pacientes com câncer de mama localmente avançado resistentes as / antraciclinas

De acordo com dados do Instituto Nacional de Câncer do Brasil, quase 30% dos pacientes novos com câncer de mama apresentam no momento do diagnóstico, tumor localmente avançado, inoperável, sendo necessário tratamento primário com quimioterapia. Usualmente esquemas baseados em antraciclinas são efetivos, porém cerca de 30% dos tumores não responderão. Para estes pacientes ainda não existe uma segunda linha de tratamento estabelecida. Objetivo: Avaliar eficácia e toxicidade de radioterapia e capecitabina como segunda linha neo-adjuvante. Pacientes e Métodos: Vinte e oito pacientes com câncer de mama localmente avançados, refratários à quimioterapia primária com antraciclinas, foram estudados entre janeiro de 2003 e maio de 2004. Os pacientes receberam radioterapia (50Gy) e capecitabina (850mg/m2) duas vezes ao dia por 14 dias cada 3 semanas. Resultados: Vinte três de 28 pacientes (82%) tornaram se operáveis. Cinco pacientes não realizaram a cirurgia por progressão de doença. A mediana do tamanho do tumor por avaliação clínica reduziu de 80 cm² para 49cm². Doença residual microscópica foi observada em 3 pacientes (13%) e resposta patológica completa em um paciente. A mediana de linfonodos acometidos foi de dois. O tratamento foi bem tolerado, sem eventos grau 3 ou 4. Conclusão: Nossos resultados indicam que o tratamento de segunda linha neo-adjuvante com radioterapia e capecitabina em pacientes com câncer de mama localmente avançado e refratários a quimioterapia primária com antraciclinas, foi eficaz e bem tolerado. Estudo randomizado e prospectivo comparando radioterapia isolada e capecitabina combinada com radioterapia deverá ser realizado

According to data from Brazil’s National Cancer Institute, nearly 30% of the new patients who present with breast cancer have locally advanced disease. These patients are inoperable, and tumor reduction is usually attempted with chemotherapy. Firstline anthracyclin-based neoadjuvant chemotherapy is often effective, but about 30% of the patients fail. For those, there is yet no established second-line treatment. Objectives: We have studied the concomitant use of radiation therapy and capecitabine in this setting, in order to determine the toxicity and efficacy of this regimen as a second-line neoadjuvant treatment. Methods: Twenty-eight patients with inoperable locally advanced breast cancer refractory to first-line anthracycline based treatment were enrolled between January 2003 and May 2004. Patients received radiation therapy (50Gy) and concomitant capecitabine (850mg/m²) for 14 days every 3 weeks. Results: This treatment rendered 23 of the 28 patients (82%) operable. The five remaining patients did not undergo surgery due to disease progression. The median clinical tumor size decreased from 80 cm2 to 49 cm2. Microscopic residual disease was observed in 3 patients (13%), and another patient achieved a complete pathologic response. The median number of involved lymph nodes was two. Treatment was well tolerated, with no grade 3 or 4 events. Conclusion: Our data indicate that second-line neoadjuvant treatment with radiation therapy and capecitabine is feasible, well tolerated and effective in patients with locally advanced breast cancer refractory to primary anthracycline-based treatment. These results suggest that a randomized study should be done to compare radiotherapy alone to capecitabine combined with radiotherapy

Ultrastructural effects of two phthalocyanines in CHO-K1 and HeLa cells after laser irradiation

The effects of Photodynamic Therapy using 2nd generation photosensitizers have been widely investigated aiming clinical application treatment of solid neoplasms. In this work, ultrastructure changes caused by the action of two 2nd generation photosensitizers and laser irradiation on CHO-K1 and HeLa (neoplastic) cells were analyzed by transmission electron microscopy. Aluminum phthalocyanine chloride, aluminum phthalocyanine tetrasulfonate chloride and radiation from a semiconductor laser at a fluency of 0.5 J/cm2 (Power=26 mW; lambda=.670 nm) were used. The results showed induction of apoptosis. Such alterations where observed in HeLa but not in CHO-K1 cells after Aluminum phthalocyanine tetrasulfonate chloride (AlPcS4, photodynamic treatment. The Aluminum phthalocyanine chloride (AlPc) photodynamic treatment induced necrosis on the neoplastic cell line, and cytoplasm and nuclear alterations on the normal cell line.

Tratamiento del cáncer de cérvix localmente avanzado (estadíos IB BULKY-IIIB) con dosis bajas bisemanales de gemcitabina más cisplatino semanal en forma concurrente con radioterapia / Treatment cervix uteri carcinoma (IB-BULKY IIIB) with low close biweekly gemcitabine and weekly cisplatin combined with radiation therapy

El tratamiento estándar para el CCLA consiste en radioterapia más qiomioterapia en forma concurrente. El agregado de gemcitabina al cisplatino es factible sin agregarle toxicidad (Abs.2150 ASCO 2001). Basándonos en esos resultados, diseñamos un estudio evaluando la eficacia y toxicidad de la radioterapia con dosis bajas bisemanales de gemcitabina más cisplatino en el CCLA. Se incluyeron 60 pacientes; la edad media fue de 49 años (r:25-76). Los estadíos en el momento del diagnóstico se distribuyeron de la siguiente manera: 17 (28 por ciento): estadíos IIIB; 40 (66,6 por ciento): IIAB; y 3: IB Bulky (la paciente tenía contraindicada la cirugía). Se administró radioterapia externa a la pelvis total en 23 fracciones, alcanzando 46 Gys. en 5 semanas, con 2 inserciones de braquiterapia al final de la tercera y quinta semana. El total de la dosis administrada al punto A fue de 85 to 90 Gys. La quimioterapia consistió en gemcitabina 20 mg/m²/d 2 veces por semana (comenzando 3 días previo a la radioterapia) y cisplatino 30 mg/m² semanalmente. Toxicidad: 60 pacientes son evaluables para toxicidad y respuesta. Tres pacientes tuvieron que demorar 1 semana la primera braquiterapia debido a toxicidad gastrointestinal. Seis pacientes debieron omitir una aplicación de QT por toxicidad hematológica y gastrointestinal. Hubo 1 muerte durante el tratamiento, no relacionada con el tratamiento. No hubo alopecia ni mucositis. Cinco pacientes tuvieron trombocitopenia G2; 1 paciente: G3. Ocho pacientes experimentaron neutropenia G2, mientras que una sola paciente tuvo G3, y una G4...

The effect of porphyrins on normal and transformed mouse cell lines in the presence of visible light

Photodynamic therapy consists of the uptake of a photosensitizing dye, often a porphyrin, by tumor tissue and subsequent irradiation of the tumor with visible light of an appropriate wavelength matched to the absorption spectrum of the photosensitizing dye. This class of molecules produces reactive oxygen species when activated by light, resulting in a direct or indirect cytotoxic effect on the target cells. Photodynamic therapy has been used in the treatment of cancer but the technology has a potential for the treatment of several disease conditions mainly because of its selectivity. However, it is not clear why the porphyrins are retained preferentially by abnormal tissue. This paper describes a study of the effect of the association of porphyrin and visible light on two mouse fibroblast cell lines: A31, normal cells and B61, an EJ-ras transformed variant of A31. Two water-soluble porphyrins were used, a positively charged one, tetra(N-methyl-4-pyridyl)porphyrin chloride, and a negatively charged one, tetra(4-sulfonatophenyl)porphyrin-Na salt (TPPS4) in order to assess the effect on cell survival. The results suggest that the B61 cell line is more sensitive to incubation with the anionic porphyrin (TPPS4) followed by light irradiation and that the anionic porphyrin is more efficient in killing the cells than the cationic porphyrin

Radio-quimioterapia concomitante en cáncer escamocelular avanzado en cabeza y cuello / Concomitant radio-chemotherapy in advanced head and neck squamocellular cancer

La radioquimioterapia concomitante aparece en los últimos años como una alternativa en el manejo de los pacientes portadores de cáncer avanzados de cabeza y cuello. En el Servicio de Otorrinolaringología del Hospital Carlos Van Buren planificamos un protocolo de estudio en pacientes portadores de cáncer escamocelular avanzados de cabeza y cuello, consistente en radioquimioterapia concomitante, 2 Gy diarios por 5 días semanales, completando 6600 a 7000 rad. asociado a cisplatino en dosis de 100 mgr/m² cada 21 días por 3 veces (los días 1,22 y 43). 30 pacientes se incluyeron en el estudio. 28 fueron analizados: 25 hombres y 3 mujeres. La edad promedio fue de 64 años. 8 casos correspondían al estadio III y 20 a estadio IV. 12 casos de localización en hipofaringe, 8 en laringe, 4 en orofaringe, 3 en cavidad oral y 1 en pirámide nasal. Se observó respuesta completa en 18 pacientes (64 por cientos), respuesta parcial en 9 pacientes (32 por ciento) y no respuesta en 1 paciente (4 por ciento). La sobrevida general fue de un 64,3 por ciento. La toxicidad renal y hematológica fueron los efectos adversos más comunes

Sintesis de nitroimidazoles 1-sustituidos y su evaluación como radiosensibilizantes / Synthesis of 1-substituted nitroimidazoles and its evaluation as radiosensitizing agents

Se describe la sístesis de varios nitroimidazoles sustituídos con cadenas lipofílicas e hidrofílicas como posibles agentes radiosensibilizantes. El material de partida empleado fue el 4(5)-nitroimidazol, el cual fue alquilado vía su sal sódica, con cadenas clorometiladas provenientes de ésteres o alcoholes, de manera de obtener análogos estructurales de compuestos de reconocida actividad rediosensibilizantes y bactericida tales como el misonidazol, metronidazol y desmetilmisonidazol. Algunos productos de esta sístesis fueron sometidos a pruebas de radiosensibilización, dando resultados negativos, bajo las condiciones ensayadas