HER2 classification in breast cancer cells: A new explainable machine learning application for immunohistochemistry.

The immunohistochemical (IHC) evaluation of epidermal growth factor 2 (HER2) for the diagnosis of breast cancer is still qualitative with a high degree of inter-observer variability, and thus requires the incorporation of complementary techniques such as fluorescent in situ hybridization (FISH) to resolve the diagnosis. Implementing automatic algorithms to classify IHC biomarkers is crucial for typifying the tumor and deciding on therapy for each patient with better performance. The present study aims to demonstrate that, using an explainable Machine Learning (ML) model for the classification of HER2 photomicrographs, it is possible to determine criteria to improve the value of IHC analysis. We trained a logistic regression-based supervised ML model with 393 IHC microscopy images from 131 patients, to discriminate between upregulated and normal expression of the HER2 protein. Pathologists' diagnoses (IHC only) vs. the final diagnosis complemented with FISH (IHC + FISH) were used as training outputs. Basic performance metrics and receiver operating characteristic curve analysis were used together with an explainability algorithm based on Shapley Additive exPlanations (SHAP) values to understand training differences. The model could discriminate amplified IHC from normal expression with better performance when the training output was the IHC + FISH final diagnosis (IHC vs. IHC + FISH: area under the curve, 0.94 vs. 0.81). This may be explained by the increased analytical impact of the membrane distribution criteria over the global intensity of the signal, according to SHAP value interpretation. The classification model improved its performance when the training input was the final diagnosis, downplaying the weighting of the intensity of the IHC signal, suggesting that to improve pathological diagnosis before FISH consultation, it is necessary to emphasize subcellular patterns of staining.

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.

TRPV1-Estradiol Stereospecific Relationship Underlies Cell Survival in Oxidative Cell Death.

17ß-estradiol is a neuronal survival factor against oxidative stress that triggers its protective effect even in the absence of classical estrogen receptors. The polymodal transient receptor potential vanilloid subtype 1 (TRPV1) channel has been proposed as a steroid receptor implied in tissue protection against oxidative damage. We show here that TRPV1 is sufficient condition for 17ß-estradiol to enhance metabolic performance in injured cells. Specifically, in TRPV1 expressing cells, the application of 17ß-estradiol within the first 3 h avoided H2O2-dependent mitochondrial depolarization and the activation of caspase 3/7 protecting against the irreversible damage triggered by H2O2. Furthermore, 17ß-estradiol potentiates TRPV1 single channel activity associated with an increased open probability. This effect was not observed after the application of 17α-estradiol. We explored the TRPV1-Estrogen relationship also in primary culture of hippocampal-derived neurons and observed that 17ß-estradiol cell protection against H2O2-induced damage was independent of estrogen receptors pathway activation, membrane started and stereospecific. These results support the role of TRPV1 as a 17ß-estradiol-activated ionotropic membrane receptor coupling with mitochondrial function and cell survival.

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.

Proteostasis and Mitochondrial Role on Psychiatric and Neurodegenerative Disorders: Current Perspectives.

Proteostasis involves processes that are fundamental for neural viability. Thus, protein misfolding and the formation of toxic aggregates at neural level, secondary to dysregulation of the conservative mechanisms of proteostasis, are associated with several neuropsychiatric conditions. It has been observed that impaired mitochondrial function due to a dysregulated proteostasis control system, that is, ubiquitin-proteasome system and chaperones, could also have effects on neurodegenerative disorders. We aimed to critically analyze the available findings regarding the neurobiological implications of proteostasis on the development of neurodegenerative and psychiatric diseases, considering the mitochondrial role. Proteostasis alterations in the prefrontal cortex implicate proteome instability and accumulation of misfolded proteins. Altered mitochondrial dynamics, especially in proteostasis processes, could impede the normal compensatory mechanisms against cell damage. Thereby, altered mitochondrial functions on regulatory modulation of dendritic development, neuroinflammation, and respiratory function may underlie the development of some psychiatric conditions, such as schizophrenia, being influenced by a genetic background. It is expected that with the increasing evidence about proteostasis in neuropsychiatric disorders, new therapeutic alternatives will emerge.

Transient Receptor Potential Vanilloid 1 Expression Mediates Capsaicin-Induced Cell Death.

The transient receptor potential (TRP) ion channel family consists of a broad variety of non-selective cation channels that integrate environmental physicochemical signals for dynamic homeostatic control. Involved in a variety of cellular physiological processes, TRP channels are fundamental to the control of the cell life cycle. TRP channels from the vanilloid (TRPV) family have been directly implicated in cell death. TRPV1 is activated by pain-inducing stimuli, including inflammatory endovanilloids and pungent exovanilloids, such as capsaicin (CAP). TRPV1 activation by high doses of CAP (>10 µM) leads to necrosis, but also exhibits apoptotic characteristics. However, CAP dose-response studies are lacking in order to determine whether CAP-induced cell death occurs preferentially via necrosis or apoptosis. In addition, it is not known whether cytosolic Ca2+ and mitochondrial dysfunction participates in CAP-induced TRPV1-mediated cell death. By using TRPV1-transfected HeLa cells, we investigated the underlying mechanisms involved in CAP-induced TRPV1-mediated cell death, the dependence of CAP dose, and the participation of mitochondrial dysfunction and cytosolic Ca2+ increase. Together, our results contribute to elucidate the pathophysiological steps that follow after TRPV1 stimulation with CAP. Low concentrations of CAP (1 µM) induce cell death by a mechanism involving a TRPV1-mediated rapid and transient intracellular Ca2+ increase that stimulates plasma membrane depolarization, thereby compromising plasma membrane integrity and ultimately leading to cell death. Meanwhile, higher doses of CAP induce cell death via a TRPV1-independent mechanism, involving a slow and persistent intracellular Ca2+ increase that induces mitochondrial dysfunction, plasma membrane depolarization, plasma membrane loss of integrity, and ultimately, cell death.

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.

Hidradenoma poroide del pie: presentación de un caso y revisión de la literatura / Poroid hidradenoma of the foot: a case report and literature review

El hidradenoma poroide fue descrito en el año 1990, por Abenoza y Ackerman, como una de las 4 variedades morfológicas de un poroma ecrino. Sus principales características son: muy baja frecuencia, localización intradérmica y aspecto sólido-quístico. Es más prevalente en la séptima década de la vida, sin predominio por género y su localización más frecuente es en cabeza y cuello. Presentamos el caso de un hidradenoma poroide del dorso del pie (AU)

Poroid hidradenoma was described in 1990, by Abenoza and Ackerman, as one the four morphological varieties of eccrine poroma. Its main characteristics: very low frequency, intradermal location and solid- cystic appearance. It is more prevalent in the seventh decade of life, with no gender predominance and the most frequent location is in the head and neck. A case of poroid hidradenoma in the foot dorsum is reported (AU)

[Human intestinal spirochetosis: clinical series and literature review]. / Espiroquetosis intestinal humana: serie clínica y revisión de la literatura.

INTRODUCTION: Human intestinal spirochetosis (HIE) is defined as colonization by spirochetes of the large intestine. Is associated with chronic diarrhea. The incidence and prevalence ranges from 0.4% to 12%. OBJECTIVE: To determine the prevalence of HIE in the Salvador's Hospital, between 2003 and 2008 in patients with a history of chronic diarrhea and without abnormalities in colonoscopy, in 2 separate groups: patients with and without a history of HIV infection. MATERIAL AND METHODS: Retrospective morphology evaluation of the large bowel endoscopic biopsies to the selected groups. RESULTS: We reviewed 115 biopsies, 98 were from HIV-negative and 17 HIV from positive patients. Two cases of intestinal spirochetosis were detected, both HIV negative, with a prevalence of 1.7%. COMMENT: The prevalence of HIE is similar to that reported in Western countries. Population studies are needed to determine the real epidemiological impact in our environment.

Espiroquetosis intestinal humana: serie clínica y revisión de la literatura / Human intestinal spirochetosis: clinical series and literature review

Introduction: Human intestinal spirochetosis (HIE) is defined as colonization by spirochetes of the large intestine. Is associated with chronic diarrhea. The incidence and prevalence ranges from 0.4% to 12%. Objective: To determine the prevalence of HIE in the Salvador's Hospital, between 2003 and 2008 in patients with a history of chronic diarrhea and without abnormalities in colonoscopy, in 2 separate groups: patients with and without a history of HIV infection. Material and Methods: Retrospective morphology evaluation of the large bowel endoscopic biopsies to the selected groups. Results: We reviewed 115 biopsies, 98 were from HIV-negative and 17 HIV from positive patients. Two cases of intestinal spirochetosis were detected, both HIV negative, with a prevalence of 1.7%. Comment: The prevalence of HIE is similar to that reported in Western countries. Population studies are needed to determine the real epidemiological impact in our environment.

Introducción: La espiroquetosis intestinal humana (EIH) se define como la colonización del intestino grueso por espiroquetas. Se asocia a diarrea crónica. Su incidencia y prevalencia van desde 0,4 a 12% Objetivo: Determinar la prevalencia de EIH en el Hospital Del Salvador, de Santiago, Chile, entre los años 2003 y 2008, en pacientes con antecedentes clínicos de diarrea crónica y colonoscopia sin hallazgos patológicos, separados en dos grupos: pacientes con y sin antecedentes de infección por VIH. Material y Método: Evaluación morfológica retrospectiva de las biopsias endoscópicas de intestino grueso de los grupos seleccionados. Resultados: Se revisaron 115 biopsias, 98 correspondieron a pacientes sin infección por VIH y 17 a pacientes seropositivos para VIH. Se detectaron dos casos de espiroquetosis intestinal, ambos en pacientes sin infección por VIH, con una prevalencia de 1,7 %. Comentario: La prevalencia de EIH es similar a la publicada en países occidentales. Se requieren estudios poblacionales para determinar el real impacto epidemiológico en nuestro medio.

Enfermedad de Dieulafoy duodenal: a propósito de un caso / A case report of Dieulafoy's disease of the duodenum

La enfermedad de Dieulafoy es una causa infrecuente de hemorragia digestiva tanto alta como baja. La gran mayoría de estas lesiones están localizadas en el cuerpo y fondo gástrico. La localización duodenal ha sido comunicada de forma ocasional. El diagnóstico generalmente es endoscópico, lo que permite, además, realizar simultáneamente el tratamiento con inyectoterapia y esclerosis, por lo que la confirmación anatomopatológica es infrecuente. Presentamos el caso de un hombre de 68 años de edad con hemorragia digestiva alta severa debido a una lesión de Dieulafoy duodenal, con confirmación histológica(AU)

Dieulafoy’s disease is a rare cause of bleeding in either the upper or lower digestive tract. The majority of lesions are located in the body or fundus of the stomach, occurring only occasionally in the duodenum. It is generally diagnosed endoscopically and subsequently managed with endoscopic injection treatment, thus the histological confirmation of the diagnosis is in frequent. We report a case of Dieulafoy’s disease in the duodenum of a 68 year old man presenting with haemorrhage of the upper digestive tract, which was confirmed by histologically(AU)

Adenocarcinoma de células claras multiquístico del riñón: presentación de serie clínica anatomopatológica y revisión de la literatura / Multicystic clear cell carcinoma of kidney: clinical series presentation and literature review

El carcinoma multiquístico de células claras del riñón es una variedad infrecuente del carcinoma de células claras, representa un 6 por ciento de los tumores quísticos del riñón y se caracteriza por tener un excelente pronóstico de sobrevida luego de la resección quirúrgica completa. Objetivos: Analizar la frecuencia y aspectos morfológicos del adenocarcinoma multiquístico de células claras del riñón. Material y método: Análisis de 217 nefrectomías por tumor renal desde 1990 hasta el año 2005 porun protocolo preestablecido. Resultados: El carcinoma multiquístico de células claras del riñón correspondió al 5,5 por ciento del total de tumores y al 6,7 por ciento del total de carcinomas de células claras, la mayoría de los tumores se encontraban en el estadio T1a de la TNM con un grado nuclear de Furhman de 1 ó 2. La sobrevida libre de enfermedad a 16 años de seguimiento es del 100 por ciento.Conclusiones: El carcinoma multiquístico de células claras del riñón, es una entidad poco frecuente, de excelente comportamiento biológico y pronóstico, que debe ser considerado dentro de los diagnósticos diferenciales de los tumores quísticos del riñón.

The multicystic carcinoma of clear cells of the kidney is an infrequent variety of the carcinoma of clear cells, represents 6 percent of the cystic tumors of the kidney and is characterized for having an excellent survival after the surgical complete resection. Objective: To analyze the frequency and morphologic aspects of the multicystic adenocarcinoma of clear cells of the kidney. Material and method: Analysis of 217 nefrectomias for renal tumor from 1990 until the year 2005 for a pre-established protocol. Results: The multicystic carcinoma of clear cells of the kidney corresponded to 5.5 percent of the whole of tumors and to 6.7 percent of the whole of carcinomas of clear cells, the majority of the tumours were meetingin the stadium T1a of the TNM with a Furhman’s nuclear grade of 1 or 2. The free survival of disease to 16 years of follow-up is 100 percent. Conclusions: The multicystic carcinoma of clear cells of the kidney, is a slightly frequent entity, of excellent biological behavior and forecast, which it must be considered inside the differential diagnoses of the cystic tumors of the kidney.