Optogenetic control of cancer cell survival in ChR2-transfected HeLa cells.

Optogenetics is a molecular biological technique involving transfection of cells with photosensitive proteins and the subsequent study of their biological effects. The aim of this study was to evaluate the effect of blue light on the survival of HeLa cells, transfected with channelrhodopsin-2 (ChR2). HeLa wild-type cells were transfected with a plasmid that contained the gene for ChR2. Transfection and channel function were evaluated by real-time polymerase chain reaction (RT-PCR), fluorescence imaging using green fluorescent protein (GFP) and flow cytometry for intracellular calcium changes using a Fura Red probe. We developed a platform for optogenetic stimulation for use within the cell culture incubator. Different stimulation procedures using blue light (467 nm) were applied for up to 24 h. Cell survival was determined by flow cytometry using propidium iodide and rhodamine probes. Change in cell survival showed a statistically significant (p < 0.05) inverse association with the frequency and time of application of the light stimulus. This change seemed to be associated with the ChR2 cis-trans-isomerization cycle. Cell death was associated with high concentrations of calcium in the cytoplasm and stimulation intervals less than the period of isomerization. It is possible to transfect HeLa cells with ChR2 and control their survival under blue light stimulation. We suggest that this practice should be considered in the future development of optogenetic systems in biological or biomedical research.

Intracellular aggregated TRPV1 is associated with lower survival in breast cancer patients.

BACKGROUND: Breast cancer is a malignant disease that represents an important public health burden. The description of new molecular markers can be important to diagnosis, classification, and treatment. Transient receptor potential vanilloid 1 (TRPV1) polymodal channel is expressed in different neoplastic tissues and cell lines of breast cancer and associated with the regulation of tumor growth, tumor neurogenesis, cancer pain, and malignant progression of cancer. In primary and metastatic breast cancer tumors, TRPV1 is expressed during neoplastic transformation, invasive behavior, and resistance to cytotoxic therapy. OBJECTIVE: The objective of this study was to describe the subcellular distribution of TRPV1 in invasive breast carcinomas and its association with survival. METHODS: In 33 cases of invasive breast carcinomas, we identified immunohistochemical and immunofluorescent expression patterns of TRPV1 compared to healthy breast tissue. We characterized the expression of TRPV1 induced by estrogens in breast cancer cell lines MCF-7 and MDA to establish a model of the TRPV1-estrogen relationship regarding the malignant potential. We examined the association of TRPV1 patterns with patients' survival with the Kaplan-Meyer model, using the log-rank test at 5 years of follow-up. The relation of TRPV1 expression patterns to the St. Gallen breast cancer subtypes was also tested. RESULTS: Based on immunohistochemical expression pattern of TRPV1, we distinguished two main categories of breast cancer tissue, a "classical category" that exhibited diffuse expression of the channel and a "non-classical category" that expressed the channel in aggregates at the ER/Golgi and/or surrounding these structures. The classical pattern of TRPV1 was associated with a higher survival rate. In breast cancer cell lines, increasing doses of estrogens induced increased TRPV1 expression with nonclassical patterns at higher doses via a mechanism dependent on ER α. CONCLUSION: The expression and distribution of TRPV1 in invasive breast carcinomas may be considered as a biomarker for prognosis of the disease and a probable therapeutic target.

Acroqueratoelastoidosis: Presentación de un caso caracterizado por ausencia de fibras elásticas / Acrokeratoelastoidosis: presentation of a case characterized by absence of elastic fibers

En el año 1953, Costa describe un cuadro clínico caracterizado por la aparición de pápulas hiperqueratóticas en márgenes laterales de manos y pies, que se asociaba en el examen histológico a cambios epidérmicos (hiperortoqueratosis y acantosis) y particularmente a la reducción y/o fragmentación de fibras elásticas, motivo por el cual esta entidad, considerada actualmente una genodermatosis, recibió el nombre de acroqueratoelastoidosis (AQE). Presentamos un caso en el que destaca la ausencia de fibras elásticas (AU)

In 1953, Costa described a clinical entity characterized by the appearance of hyperkeratotic papules on the lateral margins of the hands and feet, which was associated with epidermal changes (hyperortokeratosis and acanthosis) and to the reduction and /or fragmentation of elastic fibers at histological examination. This entity was named acrokeratoelastoidosis and is currently considered to be a genodermatosis. A case characterized by the absence of elastic fibers is reported.