LKB1 Loss Assessed by Immunohistochemistry as a Prognostic Marker to First-Line Therapy in Advanced Non-Small-Cell Lung Cancer.

(1) Background: Liver kinase B1 (LKB1) is a tumor suppressor gene involved in cell growth and metabolism. However, its alterations are not routinely assessed for guiding therapy in clinical practice. We assessed LKB1 expression by immunohistochemistry as a potential biomarker. (2) Methods: This bicentric retrospective cohort study analyzed data from patients with advanced NSCLC who initiated platinum-based chemotherapy or epidermal growth factor receptor- tyrosine kinase inhibitor (EGFR-TKI) between January 2016 and December 2020. Kaplan-Meier and Cox regression models were used for survival curves and multivariate analysis. (3) Results: 110 patients were evaluated, and the clinical stage IV predominated the lung adenocarcinoma histology. LKB1 loss was observed in 66.3% of cases. LKB1 loss was associated with non-smokers, the absence of wood smoke exposure and an EGFR wild-type status. The median progression-free survival (PFS) and overall survival (OS) in the population were 11.1 and 26.8 months, respectively, in the loss group, compared with cases exhibiting a positive expression. After an adjustment by age, smoking status, Eastern Cooperative Oncology Group Performance Score (ECOG-PS), EGFR status and type of administered therapy, LKB1 loss was significantly associated with worse PFS and OS. (4) Conclusion: Patients with an LKB1 loss had worse clinical outcomes. This study warrants prospective assessments to confirm the prognostic role of the LKB1 expression in advanced NSCLC.

Immune Milieu and Genomic Alterations Set the Triple-Negative Breast Cancer Immunomodulatory Subtype Tumor Behavior.

Triple-negative breast cancer (TNBC) is an aggressive and heterogeneous disease. Seven subtypes have been described based on gene expression patterns. Herein, we characterized the tumor biology and clinical behavior of the immunomodulatory (IM) subtype. METHODS: Formalin-fixed paraffin-embedded tumor samples from 68 high-risk (stage III-IV) TNBC patients were analyzed through microarrays, immunohistochemistry, and DNA sequencing. RESULTS: The IM subtype was identified in 24% of TNBC tumor samples and characterized by a higher intratumoral (intT) and stromal (strml) infiltration of FOXP3+ TILs (Treg) compared with non-IM subtypes. Further, PD-L1+ (>1%) expression was significantly higher, as well as CTLA-4+ intT and strml expression in the IM subtype. Differential expression and gene set enrichment analysis identified biological processes associated with the immune system. Pathway analysis revealed enrichment of the ß-catenin signaling pathway. The non-coding analysis led to seven Long Intergenic Non-Protein Coding RNAs (lincRNAs) (6 up-regulated and 1 down-regulated) that were associated with a favorable prognosis in the TNBC-IM subtype. The DNA sequencing highlighted two genes relevant to immune system responses: CTNNB1 (Catenin ß-1) and IDH1. CONCLUSION: the IM subtype showed a distinct immune microenvironment, as well as subtype-specific genomic alterations. Characterizing TNBC at a molecular and transcriptomic level might guide immune-based therapy in this subgroup of patients.

CD47-SIRPα Axis as a Biomarker and Therapeutic Target in Cancer: Current Perspectives and Future Challenges in Nonsmall Cell Lung Cancer.

CD47 is a cell surface protein in the immunoglobulin superfamily which is normally expressed at low levels in every healthy cell. It´s main physiologic function is to act as an inhibitor of phagocytosis; this occurs throughout interaction with SIRPa expressed on macrophages. Interaction between CD47 and SIRPa leads to activation of tyrosine phosphatases that inhibit myosin accumulation at the submembrane assembly site of the phagocytic synapse, resulting in phagocytosis blockade. In this way CD47 acts as a "don´t eat me signal" for healthy self-cells; accordingly, loss of CD47 leads to phagocytosis of aged or damaged cells. Taking advantage of this anti-phagocytic signal provided by CD47, many types of tumors overexpress this protein, thereby avoiding phagocytosis by macrophages and aiding in the survival of cancer cells. The aim of this review is to describe the physiologic the pathophysiologic role of CD47; summarize the available high-quality information about this molecule as a potential biomarker and/or therapeutic target in cancer; finally, we present an in-depth analysis of the available information about CD47 in association with nonsmall cell lung cancer, EGFR mutations, and tumor microenvironment.

Correlación entre el volumen molecular tumoral evaluado con PET/TC con 68Ga-PSMA y los niveles de antígeno prostático específico / Correlation between molecular tumor volume evaluated with 68Ga-PSMA PET/CT and prostatic specific antigen levels

Objetivo: Investigar la asociación entre el nivel del antígeno prostático específico (PSA) en el mismo momento de la realización de PET/TC con 68Ga-PSMA y el volumen tumoral metabólico (MTV) en pacientes con cáncer de próstata en progresión bioquímica. Métodos: En este análisis retrospectivo se estudió a 84 pacientes sometidos a PET/TC con 68Ga-PSMA, a quienes se midieron los niveles de PSA en la misma semana (Trigger-PSA). Se calculó el MTV a partir de la suma de las lesiones metastásicas. Para determinar las relaciones entre el nivel de Trigger-PSA y los hallazgos de PET/TC utilizamos la correlación de Spearman. Resultados: El MTV medio de la enfermedad ósea (mBD) fue significativamente superior al valor encontrado en los ganglios metastásicos (mLN) (139,5 frente a 17,7; p<0,05). La enfermedad se limitó a la próstata en 8 pacientes (9,5%), mLN en 21 pacientes (25%), mBD en 32 pacientes (38,1%) y las 3 localizaciones (próstata, mBD y mLN) en 17 pacientes (20,2%). En 6 pacientes (6,14%), la PET/TC con 68Ga-PSMA no fue capaz de detectar la enfermedad. Los niveles medios de Trigger-PSA en los pacientes con enfermedad limitada a próstata (2,8ng/ml), mLN (6,8ng/ml) y mBD (16,8ng/ml) fueron estadísticamente significativos (p<0,05). Los pacientes positivos tuvieron un Trigger-PSA medio de 4,3ng/ml frente a 1,5ng/ml en los pacientes negativos (p<0,05). Establecimos 3 puntos límite para la tasa de detección del nivel de Trigger-PSA:≤1ng/ml (47,3%), 1-4ng/ml (68,4%) y≥4ng/ml (96,7%). Cuando el Trigger-PSA excedió de 4ng/ml, el MTV fue superior (p<0,001). Conclusión: Los resultados evidencian la correlación de MTV con Trigger-PSA, lo cual puede tener impacto sobre el tratamiento. Sin embargo, los niveles de Trigger-PSA no permitieron distinguir entre la enfermedad localizada o a distancia. La estadificación precisa de la enfermedad podría permitir planificar la mejor estrategia terapéutica

Objective: To investigate the association between prostatic-specific antigen (PSA) levels and molecular tumor volume (MTV) measured in the 68Ga-PSMA PET/CT, both done in a short period of time, in prostate cancer patients with biochemical failure. Methods: Eighty-four patients who underwent 68Ga-PSMA PET/CT and measurement of PSA levels in the same week (trigger-PSA) were studied in this retrospective analysis. MTV was calculated from the sum of the metastatic lesions. To determine the association between trigger-PSA level and PET/CT findings, Spearman rank correlation was used. Results: The median MTV of metastatic bone disease (mBD) was significantly higher than in metastatic lymph-nodes (mLN) (139.5 versus 17.7; P<.05). Disease was limited to the prostate in 8 patients (9.5%), mLN in 21 patients (25%), mBD in 32 patients (38.1%) and the 3 sites (prostate, mLN, and mBD) in 17 patients (20.2%). In 6 patients (6.14%), 68Ga-PSMA-PET/CT was not capable of detecting disease. The median trigger-PSA levels of patients with disease limited to the prostate (2.8ng/mL), mLN (6.8ng/mL), and for mBD (16.8ng/mL) was statically significant (P<.05). Positive patients had a mean trigger-PSA of 4.3ng/mL vs 1.5ng/mL in negative patients (P<.05). We established 3 threshold-points for trigger-PSA level detection rate:≤1ng/mL (47.3%), 1-4ng/mL (68.4%) and≥4ng/mL (96.7%). When trigger-PSA exceeded 4ng/mL, the MTV was higher (P<.001). Conclusion: The correlation of MTV with trigger-PSA is demonstrated, which may have an impact on management. However, trigger-PSA levels were not capable of distinguishing between localized or distant disease. An accurate detection of disease can lead to a better therapeutic strategy

Correlation between molecular tumor volume evaluated with 68Ga-PSMA PET/CT and prostatic specific antigen levels. / Correlación entre el volumen molecular tumoral evaluado con PET/TC con 68Ga-PSMA y los niveles de antígeno prostático específico.

OBJECTIVE: To investigate the association between prostatic-specific antigen (PSA) levels and molecular tumor volume (MTV) measured in the 68Ga-PSMA PET/CT, both done in a short period of time, in prostate cancer patients with biochemical failure. METHODS: Eighty-four patients who underwent 68Ga-PSMA PET/CT and measurement of PSA levels in the same week (trigger-PSA) were studied in this retrospective analysis. MTV was calculated from the sum of the metastatic lesions. To determine the association between trigger-PSA level and PET/CT findings, Spearman rank correlation was used. RESULTS: The median MTV of metastatic bone disease (mBD) was significantly higher than in metastatic lymph-nodes (mLN) (139.5 versus 17.7; P<.05). Disease was limited to the prostate in 8 patients (9.5%), mLN in 21 patients (25%), mBD in 32 patients (38.1%) and the 3 sites (prostate, mLN, and mBD) in 17 patients (20.2%). In 6 patients (6.14%), 68Ga-PSMA-PET/CT was not capable of detecting disease. The median trigger-PSA levels of patients with disease limited to the prostate (2.8ng/mL), mLN (6.8ng/mL), and for mBD (16.8ng/mL) was statically significant (P<.05). Positive patients had a mean trigger-PSA of 4.3ng/mL vs 1.5ng/mL in negative patients (P<.05). We established 3 threshold-points for trigger-PSA level detection rate:≤1ng/mL (47.3%), 1-4ng/mL (68.4%) and≥4ng/mL (96.7%). When trigger-PSA exceeded 4ng/mL, the MTV was higher (P<.001). CONCLUSION: The correlation of MTV with trigger-PSA is demonstrated, which may have an impact on management. However, trigger-PSA levels were not capable of distinguishing between localized or distant disease. An accurate detection of disease can lead to a better therapeutic strategy.

Role of Redox Status in Development of Glioblastoma.

Glioblastoma multiforme (GBM) is a highly aggressive neoplasia, prognosis remains dismal, and current therapy is mostly palliative. There are no known risk factors associated with gliomagenesis; however, it is well established that chronic inflammation in brain tissue induces oxidative stress in astrocytes and microglia. High quantities of reactive species of oxygen into the cells can react with several macromolecules, including chromosomal and mitochondrial DNA, leading to damage and malfunction of DNA repair enzymes. These changes bring genetic instability and abnormal metabolic processes, favoring oxidative environment and increase rate of cell proliferation. In GBM, a high metabolic rate and increased basal levels of reactive oxygen species play an important role as chemical mediators in the regulation of signal transduction, protecting malignant cells from apoptosis, thus creating an immunosuppressive environment. New redox therapeutics could reduce oxidative stress preventing cellular damage and high mutation rate accompanied by chromosomal instability, reducing the immunosuppressive environment. In addition, therapies directed to modulate redox rate reduce resistance and moderate the high rate of cell proliferation, favoring apoptosis of tumoral cells. This review describes the redox status in GBM, and how this imbalance could promote gliomagenesis through genomic and mitochondrial DNA damage, inducing the pro-oxidant and proinflammatory environment involved in tumor cell proliferation, resistance, and immune escape. In addition, some therapeutic agents that modulate redox status and might be advantageous in therapy against GBM are described.

Concomitant treatment with pertussis toxin plus temozolomide increases the survival of rats bearing intracerebral RG2 glioma.

PURPOSE: Glioblastoma multiforme is the most frequent primary brain tumor, it has poor prognosis, and it remains refractory to current treatment. The success of temozolomide (TMZ) appears to be limited by the occurrence of chemoresistance. Recently, we report the use of pertussis toxin as adjuvant immunotherapy in a C6 glioma model; showing a decrease in tumoral size, it induced selective cell death in Treg cells, and it elicited less infiltration of tumoral macrophages. Here, we evaluated the cytotoxic effect of pertussis toxin in combination with TMZ for glioma treatment, both in vitro and in vivo RG2 glioma model. METHODS: We determined cell viability, cell cycle, apoptosis, and autophagy on treated RG2 cells through flow cytometry, immunofluorescence, and Western blot assays. Twenty-eight rats were divided in four groups (n = 7) for each treatment. After intracranial implantation of RG2 cells, animals were treated with TMZ (10 mg/Kg/200 µl of apple juice), PTx (2 µg/200 µl of saline solution), and TMZ + PTx. Animals without treatment were considered as control. RESULTS: We found an induction of apoptosis in around 20 % of RG2 cells, in both single treatments and in their combination. Also, we determined the presence of autophagy vesicles, without any modifications in the cell cycle in the TMZ - PTx-treated groups. The survival analyses showed an increase due to individual treatments; while in the group treated with the combination TMZ - PTx, this effect was enhanced. CONCLUSION: We show that the concomitant use of pertussis toxin plus TMZ could represent an advantage to improve the glioma treatment.

An update in the use of antibodies to treat glioblastoma multiforme.

Glioblastoma is a deadly brain disease and modest improvement in survival has been made. At initial diagnosis, treatment consists of maximum safe surgical resection, followed by temozolomide and chemoirradiation or adjuvant temozolomide alone. However, these treatments do not improve the prognosis and survival of patients. New treatment strategies are being sought according to the biology of tumors. The epidermal growth factor receptor has been considered as the hallmark in glioma tumors; thereby, some antibodies have been designed to bind to this receptor and block the downstream signaling pathways. Also, it is known that vascularization plays an important role in supplying new vessels to the tumor; therefore, new therapy has been guided to inhibit angiogenic growth factors in order to limit tumor growth. An innovative strategy in the treatment of glial tumors is the use of toxins produced by bacteria, which may be coupled to specific carrier-ligands and used for tumoral targeting. These carrier-ligands provide tumor-selective properties by the recognition of a cell-surface receptor on the tumor cells and promote their binding of the toxin-carrier complex prior to entry into the cell. Here, we reviewed some strategies to improve the management and treatment of glioblastoma and focused on the use of antibodies.

Initial immunopathogenesis of multiple sclerosis: innate immune response.

Multiple sclerosis (MS) is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. The hallmark to MS is the demyelinated plaque, which consists of a well-demarcated hypocellular area characterized by the loss of myelin, the formation of astrocytic scars, and the mononuclear cell infiltrates concentrated in perivascular spaces composed of T cells, B lymphocytes, plasma cells, and macrophages. Activation of resident cells initiates an inflammatory cascade, leading to tissue destruction, demyelination, and neurological deficit. The immunological phenomena that lead to the activation of autoreactive T cells to myelin sheath components are the result of multiple and complex interactions between environment and genetic background conferring individual susceptibility. Within the CNS, an increase of TLR expression during MS is observed, even in the absence of any apparent microbial involvement. In the present review, we focus on the role of the innate immune system, the first line of defense of the organism, as promoter and mediator of cross reactions that generate molecular mimicry triggering the inflammatory response through an adaptive cytotoxic response in MS.

Application of nanoparticles on diagnosis and therapy in gliomas.

Glioblastoma multiforme (GBM) is one of the most deadly diseases that affect humans, and it is characterized by high resistance to chemotherapy and radiotherapy. Its median survival is only fourteen months, and this dramatic prognosis has stilled without changes during the last two decades; consequently GBM remains as an unsolved clinical problem. Therefore, alternative diagnostic and therapeutic approaches are needed for gliomas. Nanoparticles represent an innovative tool in research and therapies in GBM due to their capacity of self-assembly, small size, increased stability, biocompatibility, tumor-specific targeting using antibodies or ligands, encapsulation and delivery of antineoplastic drugs, and increasing the contact surface between cells and nanomaterials. The active targeting of nanoparticles through conjugation with cell surface markers could enhance the efficacy of nanoparticles for delivering several agents into the tumoral area while significantly reducing toxicity in living systems. Nanoparticles can exploit some biological pathways to achieve specific delivery to cellular and intracellular targets, including transport across the blood-brain barrier, which many anticancer drugs cannot bypass. This review addresses the advancements of nanoparticles in drug delivery, imaging, diagnosis, and therapy in gliomas. The mechanisms of action, potential effects, and therapeutic results of these systems and their future applications in GBM are discussed.

Adjuvant immunotherapy of C6 glioma in rats with pertussis toxin.

PURPOSE: In spite of the recent advances in surgery and antitumor drugs, the brain tumors, like glioblastoma, have shown a poor prognosis. The aim of this study was to determine the effect of pertussis toxin (PTx) as immunomodulatory molecule on glial tumors induced by C6 glioma cells. METHODS: Given the pleiotropic effect of PTx on the immune system, we analyzed the effect of PTx on CD4+/CD25+/FoxP3+ (Treg) cells like as immunotherapeutic adjuvant. Thirty rats with a glial tumor of 1.5 cm in diameter were separated in two groups: the first group was treated with PTx and the second group was non-treated (controls). Tumoral volume was measured weekly; tumor, blood and spleen were taken for analysis of subpopulations of T cells, apoptotic index and cytokine contents, in both groups. RESULTS: We observed a significant decrease in tumor volume in the PTx group; this was associated with a decreased in the number of Treg cells, in both spleen and tumor. The percentage of apoptotic cells was increased as compared with that of controls. The production of proinflammatory cytokines was increased in mRNA for IL-6 as well as a small increase in the mRNA expression of perforin and granzime in tumors from rats treated with PTx. No changes were found in the mRNA expression of MCP-1 and MIP-1α. CONCLUSION: These results suggest that PTx could be an immunotherapeutic adjuvant in the integral therapy against glial tumors.