Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.

Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field

Comparação das contagens das células de Langerhans de tecidos contendo carcinoma anal em doentes com e sem infecção pelo HIV Comparison of Langerhans cells counts from tissues containing anal carcinoma of patients with and without HIV infection

INTRODUÇÃO: As células de Langerhans (LC) são derivadas da medula óssea e constituem-se nas principais apresentadoras de antígeno da pele.conferindo desta forma, a resposta imune cutânea. Seu número está reduzido nos imunodeprimidos, incluindo na infecção pelo HIV, e a presença do tumor inibe sua migração, impedindo que os linfócitos T promovam regressão das células neoplásicas. OBJETIVO: Conhecer as diferenças entre as contagens de LC no tecido tumoral de doentes de carcinomas anais com e sem AIDS. MÉTODO: Avaliamos 24 doentes, sendo 14 com HIV e 10 outros sem HIV . O tratamento para o carcinoma foi semelhante nos dois grupos. Cortes retirados de blocos parafinados submetidos ao teste imunoistoquímico com anticorpo anti-CD68. Contamos as LC com método da histometria e os comparamos aos números obtidos com amostras previamente conhecidas de doentes sem doença infecciosa anorretal ou infecção pelo HIV. Revisamos também a evolução e as contagens séricas de linfócitos T CD4+ de doentes HIV-positivos. RESULTADOS: Observamos que o carcinoma anal foi mais freqüente em mulheres HIV-negativas e em homens HIV-positivos e que esses ultimos eram mais jovens. As LC foram menos numerosas nos doentes HIV-positivos e as maiores contagens estavam associadas com pior evolução. Os doentes HIV-positivos com os níveis mais baixos de linfócitos T CD4+ também tiveram as piores evoluções. CONCLUSÃO: Concluímos que as LC estavam diminuídas nos doentes HIV-positivos, portadores de carcinoma anal, quando comparados aos soronegativos.<br>Langerhans cells (LC) are bone marrow derived dendritic cells that represent the major antigen-presenting cells (APC) in the skin, thus representing an integral part of the cutaneous immune response. Immunossupression decreases their number, including HIV infection, and skin tumors products are sufficient to immobilize LC within the tumor, preventing their migration to lymph nodes. This reduces the number of T cells that infiltrate the tumor, preventing regression. OBJETIVE: Our proposal was to know what are the differences among LC counts comparing HIV-positive and -negative patients with anal carcinoma. METHOD: We evaluated 24 patients, 14 with HIV and 10 HIV-negative. Treatment for carcinoma was similar in both groups. Paraffin blocks containing biopsies were cut and stained with antibody anti-CD68. LC were counted in a histometrical way and number were compared to previous known specimens of HIV-negative patients without infectious anorectal diseases. We also studied cancer evolution and T CD4+ lymphocytes blood counts of HIV-positive patients. RESULTS: Statistics showed that anal carcinomas were more frequent in females HIV-negative and in seropositive males. HIV-positive patients were younger than seronegative ones. LC were decreased in seropositive patients and the most numerous counts were associated to worse prognosis. HIV-positive patients who had the most decreased T CD4+ counts had the worst prognosis, too. CONCLUSION: We conclude that LC were decreased in HIV-positive patients with anal carcinoma rather than in seronegative