Immunotherapy in prostate cancer: review of the current evidence.

Prostate cancer is the most common male malignancy in the Western world. Once it metastasizes, it is incurable. The current gold standard for metastatic disease is the combined docetaxel/prednisone regimen. Prostate cancer shows several characteristics that make it a suitable candidate for immunotherapy, as recently exemplified by the approval of sipuleucel-T, the first vaccine to treat any malignancy. Here, we review different tumor-associated antigen immunotherapy strategies currently being investigated, from a humanized radiolabeled monoclonal antibody (J-591) that targets radiation into tumor cells, moving on to vaccines and through to immunomodulator agents such as anti-CPLA-4 and anti-PD-1 monoclonal antibodies that activate T-cell responses via immune checkpoint inhibition. We explore different opinions on the best approach to integrate immunotherapy into existing standard therapies, such as androgen-deprivation therapy, radiotherapy or chemotherapy, and review different combination sequences, patient types and time points during the course of the disease to achieve a lasting immune response. We present data from recent phase III clinical trials that call for a change in trial endpoint design with immunotherapy agents, from the traditional tumor progression to overall survival and how such trials should include immune response measurements as secondary or intermediate endpoints to help identify patient clinical benefit in the earlier phases of treatment. Finally, we join in the recent questioning on the validity of RECIST criteria to measure response to immunotherapeutic agents, as initial increases in the size of tumors/lymph nodes, which are part of a normal immune response, could be categorized as disease progression under RECIST.

Environmental lead in Mexico.

From the data presented here, it can be concluded that environmental exposure to lead is a particularly severe problem in Mexico. As has been shown, there are very important sources of exposure to this metal: (a) for rural populations who manufacture and/or utilize lead-glazed pottery, (b) for urban populations who are exposed to high air lead concentrations due to the continued use of lead fuel additives, (c) for workers of several industries, mainly those of batteries and pigments, (d) for consumers who routinely eat canned foods such as hot peppers and fruit products, and (e) for the general population living in the vicinity of smelters, refineries and other industries that emit lead. Therefore, in Mexico only those native populations living in very primitive communities, far away from all civilized life, could be expected to be free from this exposure. At the same time, and despite the relatively few data available, it can be stated that the exposure to lead of populations in Mexico could be approaching levels that might be highly hazardous, in particular for the neuropsychological health of children. Regarding the presence of lead in the environment, despite the fact that the available studies are not enough, it is evident that pollution by this metal is widespread and that there is a serious lack of studies for most regions of the country, including several that might be expected to be highly polluted. At the same time, it is evident that the official attention paid to the problem, either in regulations, support of further studies, or implementation of effective control measures has been far from the level needed according to the available data. Lead in gasoline is still used at very high concentrations in all the country, with the exception of Mexico City and its surrounding area, while no studies have been carried out to determine the potential health and environmental impact of this practice in regions outside Mexico City. Despite the fact that the Torreón smelter is one of the largest in Latin America, and although it is located less than two km from downtown Torreón, with the predominant winds blowing in the direction from the smelter towards the residential and central areas of the city, no large scale study has been carried out on the impact of this source on the health of its residents.(ABSTRACT TRUNCATED AT 400 WORDS)