Small molecule inhibitors targeting regulatory T cells for cancer treatment.

Regulatory T cells (Tregs) are important controllers of the immune system homeostasis by preventing disproportionate immune responses. In the context of cancer, Tregs contribute to tumor development by suppressing other immune cells in the tumor microenvironment (TME). Infiltration of Tregs in the TME has been associated with poor prognosis in cancer patients. Thus, understanding the mechanisms underlying Treg recruitment and suppressive functions is essential for developing cancer immunotherapies to boost antitumor immune responses. While antibody-based strategies targeting Tregs have shown promise, small molecule inhibitors offer distinct advantages, including oral bioavailability and the ability to penetrate the TME and target intracellular proteins. Here, we provide an overview of small molecule inhibitors that have demonstrated efficacy in modulating Tregs activity in cancer and highlight the need for phenotypic assays to characterize therapeutic compounds.

Activity and safety of topical pimecrolimus in patients with early stage mycosis fungoides (PimTo-MF): a single-arm, multicentre, phase 2 trial.

BACKGROUND: The calcineurin pathway is often activated in mycosis fungoides. We aimed to assess the activity and safety of topical pimecrolimus, a calcineurin inhibitor, in patients with early mycosis fungoides. METHODS: PimTo-MF was a single-arm, multicentre, phase 2 trial done at six medical centres in Spain. Patients (aged ≥18 years) had histologically confirmed early mycosis fungoides (stages IA-IIA) and an Eastern Cooperative Oncology Group performance status of 0-1. Key exclusion criteria included the use of concurrent treatments for mycosis fungoides, including sunbathing, topical or systemic corticosteroids, and other calcineurin inhibitors. Patients applied topical pimecrolimus 1% cream on their skin lesions twice daily for 16 weeks (1 g per 2% of body surface), with subsequent follow-up of 12 months. Dosage modifications were not allowed. To evaluate adherence to the treatment, patients were instructed to return all empty tubes to the hospital (as per drug accountability protocols). The primary endpoint was the overall response ratein the intention-to-treat population. PimTo-MF is registered with EudraCT, 2014-001377-14, and is complete. FINDINGS: Between March 1, 2015, and Sept 30, 2016, 39 patients were enrolled. All patients were assessable, with a median age of 51·5 years (IQR 45-62), and the population was predominantly male (24 male [62%], 15 female [38%]). Median follow-up after baseline was 5·7 years (IQR 5·7-6·2). 22 (56%) of 39 patients had an overall response (one complete response, 21 partial responses). Responses were observed across IA (14 [54%] of 26 patients) and IB (eight [73%] of 11 patients) clinical stages, but not IIA. Topical pimecrolimus was well tolerated and no patient required a dose reduction or discontinued treatment because of unacceptable drug-related toxicity. No patients were lost to follow-up or discontinued treatment. 13 (33%) of 39 patients reported adverse events; transitory mild burning or pruritus (grade 1) was the most common, seen in eight (21%) patients. In three (8%) of these patients, the burning or pruritus was considered related to treatment. No grade 4 or 5 adverse events were observed. INTERPRETATION: Pimecrolimus 1% cream seems active and safe in patients with early stage mycosis fungoides. Our findings should be taken with caution until long-term follow-up data are obtained that confirm the safety of this treatment. Further controlled clinical trials are warranted to confirm these results. FUNDING: Instituto de Salud Carlos III and the European Regional Development Fund. TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.

PLCγ1/PKCθ Downstream Signaling Controls Cutaneous T-Cell Lymphoma Development and Progression.

Developing mechanistic rationales can improve the clinical management of cutaneous T-cell lymphomas. There is considerable genetic and biological evidence of a malignant network of signaling mechanisms, highly influenced by deregulated TCR/PLCγ1 activity, controlling the biology of these lesions. In addition, activated signal transducer and activator of transcription 3 is associated with clinical progression, although the alterations responsible for this have not been fully elucidated. Here, we studied PLCγ1-dependent mechanisms that can mediate STAT3 activation and control tumor growth and progression. Downstream of PLCγ1, the pharmacological inhibition and genetic knockdown of protein kinase C theta (PKCθ) inhibited signal transducer and activator of transcription 3 activation, impaired proliferation, and promoted apoptosis in cutaneous T-cell lymphoma cells. A PKCθ-dependent transcriptome in mycosis fungoides/Sézary syndrome cells revealed potential effector genes controlling cytokine signaling, TP53, and actin cytoskeleton dynamics. Consistently, an in vivo chicken embryo model xenografted with mycosis fungoides cells showed that PKCθ blockage abrogates tumor growth and spread to distant organs. Finally, the expression of a number of PKCθ target genes found in mycosis fungoides cells significantly correlated with that of PRKCQ (PKCθ) in 81 human mycosis fungoides samples. In summary, PKCθ can play a central role in the activation of malignant cutaneous T-cell lymphoma mechanisms via multiple routes, including, but not restricted to, STAT3. These mechanisms may, in turn, serve as targets for specific therapies.

Mycosis Fungoides and Sézary Syndrome: An Integrative Review of the Pathophysiology, Molecular Drivers, and Targeted Therapy.

Primary cutaneous T-cell lymphomas (CTCLs) constitute a heterogeneous group of diseases that affect the skin. Mycosis fungoides (MF) and Sézary syndrome (SS) account for the majority of these lesions and have recently been the focus of extensive translational research. This review describes and discusses the main pathobiological manifestations of MF/SS, the molecular and clinical features currently used for diagnosis and staging, and the different therapies already approved or under development. Furthermore, we highlight and discuss the main findings illuminating key molecular mechanisms that can act as drivers for the development and progression of MF/SS. These seem to make up an orchestrated constellation of genomic and environmental alterations generated around deregulated T-cell receptor (TCR)/phospholipase C, gamma 1, (PLCG1) and Janus kinase/ signal transducer and activator of transcription (JAK/STAT) activities that do indeed provide us with novel opportunities for diagnosis and therapy.

Identification of tipifarnib sensitivity biomarkers in T-cell acute lymphoblastic leukemia and T-cell lymphoma.

Patients diagnosed with T-cell leukemias and T-cell lymphomas (TCLs) still have a poor prognosis and an inadequate response to current therapies, highlighting the need for targeted treatments. We have analyzed the potential therapeutic value of the farnesyltransferase inhibitor, tipifarnib, in 25 TCL cell lines through the identification of genomic and/or immunohistochemical markers of tipifarnib sensitivity. More than half of the cell lines (60%) were considered to be sensitive. Tipifarnib reduced cell viability in these T-cell leukemia and TCL cell lines, induced apoptosis and modified the cell cycle. A mutational study showed TP53, NOTCH1 and DNMT3 to be mutated in 84.6%, 69.2% and 30.0% of sensitive cell lines, and in 62.5%, 0% and 0% of resistant cell lines, respectively. An immunohistochemistry study showed that p-ERK and RelB were associated as potential biomarkers of tipifarnib sensitivity and resistance, respectively. Data from RNA-seq show that tipifarnib at IC50 after 72 h downregulated a great variety of pathways, including those controlling cell cycle, metabolism, and ribosomal and mitochondrial activity. This study establishes tipifarnib as a potential therapeutic option in T-cell leukemia and TCL. The mutational state of NOTCH1, p-ERK and RelB could serve as potential biomarkers of tipifarnib sensitivity and resistance.

Dopaminergic control of ADAMTS2 expression through cAMP/CREB and ERK: molecular effects of antipsychotics.

A better understanding of the molecular mechanisms that participate in the development and clinical manifestations of schizophrenia can lead to improve our ability to diagnose and treat this disease. Previous data strongly associated the levels of deregulated ADAMTS2 expression in peripheral blood mononuclear cells (PBMCs) from patients at first episode of psychosis (up) as well as in clinical responders to treatment with antipsychotic drugs (down). In this current work, we performed an independent validation of such data and studied the mechanisms implicated in the control of ADAMTS2 gene expression. Using a new cohort of drug-naïve schizophrenia patients with clinical follow-up, we confirmed that the expression of ADAMTS2 was highly upregulated in PBMCs at the onset (drug-naïve patients) and downregulated, in clinical responders, after treatment with antipsychotics. Mechanistically, ADAMTS2 expression was activated by dopaminergic signalling (D1-class receptors) and downstream by cAMP/CREB and mitogen-activated protein kinase (MAPK)/ERK signalling. Incubation with antipsychotic drugs and selective PKA and MEK inhibitors abrogated D1-mediated activation of ADAMTS2 in neuronal-like cells. Thus, D1 receptors signalling towards CREB activation might participate in the onset and clinical responses to therapy in schizophrenia patients, by controlling ADAMTS2 expression and activity. The unbiased investigation of molecular mechanisms triggered by antipsychotic drugs may provide a new landscape of novel targets potentially associated with clinical efficacy.

Applied diagnostics in liver cancer. Efficient combinations of sorafenib with targeted inhibitors blocking AKT/mTOR.

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. There is increasing interest in developing specific markers to serve as predictors of response to sorafenib and to guide targeted therapy. Using a sequencing platform designed to study somatic mutations in a selection of 112 genes (HepatoExome), we aimed to characterize lesions from HCC patients and cell lines, and to use the data to study the biological and mechanistic effects of case-specific targeted therapies used alone or in combination with sorafenib. We characterized 331 HCC cases in silico and 32 paired samples obtained prospectively from primary tumors of HCC patients. Each case was analyzed in a time compatible with the requirements of the clinic (within 15 days). In 53% of the discovery cohort cases, we detected unique mutational signatures, with up to 34% of them carrying mutated genes with the potential to guide therapy. In a panel of HCC cell lines, each characterized by a specific mutational signature, sorafenib elicited heterogeneous mechanistic and biological responses, whereas targeted therapy provoked the robust inhibition of cell proliferation and DNA synthesis along with the blockage of AKT/mTOR signaling. The combination of sorafenib with targeted therapies exhibited synergistic anti-HCC biological activity concomitantly with highly effective inhibition of MAPK and AKT/mTOR signaling. Thus, somatic mutations may lead to identify case-specific mechanisms of disease in HCC lesions arising from multiple etiologies. Moreover, targeted therapies guided by molecular characterization, used alone or in combination with sorafenib, can effectively block important HCC disease mechanisms.

Individualized strategies to target specific mechanisms of disease in malignant melanoma patients displaying unique mutational signatures.

Targeted treatment of advanced melanoma could benefit from the precise molecular characterization of melanoma samples. Using a melanoma-specific selection of 217 genes, we performed targeted deep sequencing of a series of biopsies, from advanced melanoma cases, with a Breslow index of ≥ 4 mm, and/or with a loco-regional infiltration in lymph nodes or presenting distant metastasis, as well of a collection of human cell lines. This approach detected 3-4 mutations per case, constituting unique mutational signatures associated with specific inhibitor sensitivity. Functionally, case-specific combinations of inhibitors that simultaneously targeted MAPK-dependent and MAPK-independent mechanisms were most effective at inhibiting melanoma growth, against each specific mutational background. These observations were challenged by characterizing a freshly resected biopsy from a metastatic lesion located in the skin and soft tissue and by testing its associated therapy ex vivo and in vivo using melanocytes and patient-derived xenografted mice, respectively. The results show that upon mutational characterization of advanced melanoma patients, specific mutational profiles can be used for selecting drugs that simultaneously target several deregulated genes/pathways involved in tumor generation or progression.

Clorhidrato de ketamina: técnicas analíticas necesarias para el desarrollo tecnológico / Ketamine hydrochloride: analytical techniques needed for technological development

El desarrollo tecnológico requiere de métodos analíticos confiables que permitan la cuantificación del fármaco en diferentes etapas de la investigación. El objetivo de este trabajo fue las validaciones prospectivas de 2 métodos analíticos, uno por UV-VIS y otro por cromatografía líquida de alta eficiencia, desarrolladas para el control del proceso de fabricación, de la calidad y para el estudio de estabilidad de ketamina. A las técnicas se le determinaron los parámetros de desempeño, especificidad, linealidad, exactitud, rango y precisión. Los resultados alcanzados permiten concluir que ambos métodos cumplen con los requisitos establecidos como aceptables para cada uno de los casos en el rango de concentraciones establecido. El método espectrofotométrico puede utilizarse en el control del proceso de producción y el control de calidad del producto terminado al igual que el método cromatográfico; el primero, es de elección para el control de proceso de fabricación por su sencillez y rapidez, y el segundo, para el estudio de estabilidad del producto por su elevada especificidad.

Technological development requires of reliable and analytical methods to quantify drugs in different stages of research. Aim of present paper was the prospective validations of two analytical methods, one by UV-VIS, and the other by high performance liquid chromatography, developed to control of manufacture process, quality, and to study of Ketamine stability. Techniques included the following parameters: performance, specificity, linearity, accuracy, rank, and precision. Results achieved allow concluding that both methods fulfill the criteria established as fair to each of the cases in rank of concentrations stetted. Spectrophotometry method may be used in control of production process and in control of quality of end product just like the chromatography method, the first one, is the choice to control of manufacture process due to its simplicity and speed, and the second one, to study of product stability due to its high specificity.

Clorhidrato de ketamina: técnicas analíticas necesarias para el desarrollo tecnológico / Ketamine hydrochloride: analytical techniques needed for technological development

El desarrollo tecnológico requiere de métodos analíticos confiables que permitan la cuantificación del fármaco en diferentes etapas de la investigación. El objetivo de este trabajo fue las validaciones prospectivas de 2 métodos analíticos, uno por UV-VIS y otro por cromatografía líquida de alta eficiencia, desarrolladas para el control del proceso de fabricación, de la calidad y para el estudio de estabilidad de ketamina. A las técnicas se le determinaron los parámetros de desempeño, especificidad, linealidad, exactitud, rango y precisión. Los resultados alcanzados permiten concluir que ambos métodos cumplen con los requisitos establecidos como aceptables para cada uno de los casos en el rango de concentraciones establecido. El método espectrofotométrico puede utilizarse en el control del proceso de producción y el control de calidad del producto terminado al igual que el método cromatográfico; el primero, es de elección para el control de proceso de fabricación por su sencillez y rapidez, y el segundo, para el estudio de estabilidad del producto por su elevada especificidad(AU)

Technological development requires of reliable and analytical methods to quantify drugs in different stages of research. Aim of present paper was the prospective validations of two analytical methods, one by UV-VIS, and the other by high performance liquid chromatography, developed to control of manufacture process, quality, and to study of Ketamine stability. Techniques included the following parameters: performance, specificity, linearity, accuracy, rank, and precision. Results achieved allow concluding that both methods fulfill the criteria established as fair to each of the cases in rank of concentrations stetted. Spectrophotometry method may be used in control of production process and in control of quality of end product just like the chromatography method, the first one, is the choice to control of manufacture process due to its simplicity and speed, and the second one, to study of product stability due to its high specificity(AU)

Desarrollo y validación de una metodología para la limpieza de áreas de producción de tabletas de penicilamina / Development and validation of a methodology for cleaning areas of production of penicillamine tablets

Se desarrolló una metodología de limpieza para aplicar en áreas de producción y desarrollo donde se trabaje con penicilamina, un compuesto altamente contaminante y tóxico. Se validó un método por cromatografía líquida de alta eficiencia que fue seleccionado por la versatilidad de este tipo de técnicas para la detección de trazas. El método resultó específico, lineal, exacto y preciso en el rango de concentraciones de trabajo. Se determinaron los límites de detección y cuantificación. Se utilizó el método de muestreo por hisopado, con el que se obtuvieron resultados satisfactorios y se concluyó que los procedimientos de limpieza resultaron efectivos para el peor de los escenarios

Desarrollo y validación de una metodología para la limpieza de áreas de producción de tabletas de penicilamina / Development and validation of a methodology for cleaning areas of production of penicillamine tablets

Se desarrolló una metodología de limpieza para aplicar en áreas de producción y desarrollo donde se trabaje con penicilamina, un compuesto altamente contaminante y tóxico. Se validó un método por cromatografía líquida de alta eficiencia que fue seleccionado por la versatilidad de este tipo de técnicas para la detección de trazas. El método resultó específico, lineal, exacto y preciso en el rango de concentraciones de trabajo. Se determinaron los límites de detección y cuantificación. Se utilizó el método de muestreo por hisopado, con el que se obtuvieron resultados satisfactorios y se concluyó que los procedimientos de limpieza resultaron efectivos para el peor de los escenarios(AU)

Determinación de atropina sulfato y difenoxilato clorhidrato en reasec tabletas. Validación / Determination of atropine sulphate and diphenoxilate chlorhydrate in Reasec tablets. Validation

El reasec es un antidiarreico cuyo efecto viene dado por la asociación de 2 principios activos, atropina sulfato y difenoxilato clorhidrato. La unión de ambos trae como resultado la inhibición del peristaltismo del tracto gastrointestinal que puede ser posible tanto a nivel central como local. De la literatura revisada para el caso del difenoxilato clorhidrato se escogió el método por cromatografía líquida de alta eficiencia por aprovechar la posibilidad de que se trataba del método propuesto en el registro de medicamentos para el estudio de estabilidad en la formulación de este principio activo. El método para la determinación de atropina sulfato se encuentra reportado en la USP 23 y el criterio de selección fue uno de los menos complejos en la cuantificación de esta. Teniendo en cuenta las regulaciones establecidas que aseguran el cumplimiento de las buenas prácticas de producción, el presente trabajo se propone la validación prospectiva de los métodos para la cuantificación de los principios activos componentes del reasec, por lo que se realizaron los estudios de especificidad, exactitud, precisión, linealidad y rango. En ambos casos se cumplieron con los requisitos establecidos a los métodos analíticos que se encuentran dentro de la categoría I por ser empleados para la cuantificación de los componentes activos de la formulación. Los resultados obtenidos demostraron que ambos métodos analíticos son fiables por permitir la cuantificación de los 2 principios activos y cumplir además, con los requisitos establecidos para los parámetros evaluados dentro de la categoría a la que pertenecen cada uno

Determinación de atropina sulfato y difenoxilato clorhidrato en reasec tabletas: validación / Determination of atropine sulfate and difenoxilato hydrochlorate in reasec pills: validation

El reasec es un antidiarreico cuyo efecto viene dado por la asociación de 2 principios activos, atropina sulfato y difenoxilato clorhidrato. La unión de ambos trae como resultado la inhibición del peristaltismo del tracto gastrointestinal que puede ser posible tanto a nivel central como local. De la literatura revisada para el caso del difenoxilato clorhidrato se escogió el método por cromatografía líquida de alta eficiencia por aprovechar la posibilidad de que se trataba del método propuesto en el registro de medicamentos para el estudio de estabilidad en la formulación de este principio activo. El método para la determinación de atropina sulfato se encuentra reportado en la USP 23 y el criterio de selección fue uno de los menos complejos en la cuantificación de esta. Teniendo en cuenta las regulaciones establecidas que aseguran el cumplimiento de las buenas prácticas de producción, el presente trabajo se propone la validación prospectiva de los métodos para la cuantificación de los principios activos componentes del reasec, por lo que se realizaron los estudios de especificidad, exactitud, precisión, linealidad y rango. En ambos casos se cumplieron con los requisitos establecidos a los métodos analíticos que se encuentran dentro de la categoría I por ser empleados para la cuantificación de los componentes activos de la formulación. Los resultados obtenidos demostraron que ambos métodos analíticos son fiables por permitir la cuantificación de los 2 principios activos y cumplir además, con los requisitos establecidos para los parámetros evaluados dentro de la categoría a la que pertenecen cada uno(AU)