Podoplanin in Inflammation and Cancer.

Podoplanin is a small cell-surface mucin-like glycoprotein that plays a crucial role in the development of the alveoli, heart, and lymphatic vascular system. Emerging evidence indicates that it is also involved in the control of mammary stem-cell activity and biogenesis of platelets in the bone marrow, and exerts an important function in the immune response. Podoplanin expression is upregulated in different cell types, including fibroblasts, macrophages, T helper cells, and epithelial cells, during inflammation and cancer, where it plays important roles. Podoplanin is implicated in chronic inflammatory diseases, such as psoriasis, multiple sclerosis, and rheumatoid arthritis, promotes inflammation-driven and cancer-associated thrombosis, and stimulates cancer cell invasion and metastasis through a variety of strategies. To accomplish its biological functions, podoplanin must interact with other proteins located in the same cell or in neighbor cells. The binding of podoplanin to its ligands leads to modulation of signaling pathways that regulate proliferation, contractility, migration, epithelial⁻mesenchymal transition, and remodeling of the extracellular matrix. In this review, we describe the diverse roles of podoplanin in inflammation and cancer, depict the protein ligands of podoplanin identified so far, and discuss the mechanistic basis for the involvement of podoplanin in all these processes.

Nivolumab plus ipilimumab in metastatic melanoma: a critical appraisal focused on specific subpopulations.

The development of immune checkpoint inhibitors has revolutionized the landscape of treatment of advanced melanoma in recent years. Based on the efficacy results of the phase III CheckMate 067 trial, nivolumab in combination with ipilimumab is one of the first-line standard options for advanced melanoma along with pembrolizumab, nivolumab, and, recently, nivolumab plus relatlimab. Counterbalancing its efficacy, nivolumab plus ipilimumab is associated with severe immune-related toxicity. This article will review the efficacy and safety of the nivolumab plus ipilimumab combination in advanced melanoma across phase I, II, and III clinical trials that evaluated this approach. We also explore the benefit of the combination schedule across different subgroups of patients and possible predictive biomarkers for efficacy outcomes in order to elucidate which patients could be the best candidates for combination or single-agent therapy. Patients with BRAF-mutant tumours, asymptomatic brain metastases, or PD-L1-negative status appear to reach better survival outcomes with the combination relative to single-agent immunotherapy.

Sarcoidosis-like reaction induced by immune checkpoint inhibitor in a patient with hepatocellular carcinoma: a case report.

Nowadays, immune checkpoint inhibitors (ICI) have become the cornerstone of treatment for many tumors, either as monotherapy or in combination with other therapies. However, these drugs are associated with several new side effects that need early detection. We present the case of a 41-year-old male patient who has been diagnosed with advanced hepatocellular carcinoma (HCC) with metastatic retroperitoneal lymph nodes and a subdiaphragmatic metastatic lesion, undergoing second-line treatment with a combination of nivolumab and ipilimumab. After completing four cycles, the patient was admitted to the hospital due to intermittent fever and profuse sweating. A CT scan showed multiple pathologically enlarged lymph nodes in several locations, raising suspicion of disease progression. The patient's clinical progress was favorable after symptomatic treatment (antipyretics) and was discharged one week after admission. Several days later, the patient complained about painful bilateral ocular redness and was diagnosed with bilateral anterior uveitis. Further blood tests showed elevated angiotensin-converting enzyme (ACE) levels of 67 U/L (normal range: 8 - 52) and decreasing alpha-fetoprotein (AFP) levels of 698 ng/mL (previously 1210 ng/mL), indicative of non-progression of the oncological disease. Finally, an excisional biopsy confirmed the presence of non-necrotizing granulomatous lymphadenitis, leading to the diagnosis of sarcoidosis-like reaction (SLR) induced by immunotherapy as the etiology of the polyadenopathy syndrome. SLR, although uncommon, is an adverse effect of ICI treatment resulting from immune system dysregulation, which can mimic disease progression. It is crucial to be aware of this adverse event and to understand the optimal management approach.

Argentinean Psycholinguistic Picture Naming Test in color.

Color has demonstrated to have an influence on picture naming tasks. Objects with high color diagnosticity are recalled faster than objects with low value. That is why the Argentinean Psycholinguistic Picture Naming Test in color (PAPDIC in Spanish) was designed. The items and semantic cues were built considering local psycholinguistic norms. A series of psychometric analyses were performed on a sample of patients with focal brain damage with (n = 11) and without (n = 14) aphasia, a sample of patients with degenerative disease (n = 46) and two samples of healthy participants (young n = 27, old n = 50). Evidence of convergent validity was obtained through the correlation with the brief Boston Naming Test (r = 0.871; p < .001); of criteria validity by means of contrasted groups analysis (t = 4.059, p < .001), and through the ROC curve analysis (AUC = 0.993). Scores' reliability was explored by means of an internal consistency analysis (KR20 = 0.905). These results indicate that the PAPDIC is a promising color naming test which can be applied in the field of clinical neuropsychology to identify anomia. This test has several advantages in comparison with the available naming tests in Argentina.

Persistence of SARS-CoV-2 Infection in Severely Immunocompromised Patients With Complete Remission B-Cell Lymphoma and Anti-CD20 Monoclonal Antibody Therapy: A Case Report of Two Cases.

Immunosuppressant conditions such as hematological malignancies increase the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. It has been described in the literature that patients on anti-CD20 maintenance therapies for lymphoid malignancies are susceptible to having recurrent flares together with viral replication or reinfections, although these cases are scarce. These patients are not well represented in randomized controlled trials, and as a consequence, the evidence for the use of certain treatments in this scenario is lacking. We present two cases of patients with B-cell lymphoma on remission and treated with rituximab on maintenance. They developed at least 1 flare of coronavirus disease 2019 (COVID-19) after acute infection and always after receiving rituximab. RT-PCR was positive in the nasopharyngeal swab and also in plasma. Patients were treated during flares with remdesivir, hyperimmune plasma, and corticosteroids. These two cases showed the unresolved problem of COVID-19 in immunosuppressant patients and showed that despite the vast amount of information available on SARS-CoV-2, information in this subgroup of patients is lacking.

Frontotemporal Dementias in Latin America: History, Epidemiology, Genetics, and Clinical Research.

Introduction: The historical development, frequency, and impact of frontotemporal dementia (FTD) are less clear in Latin America than in high-income countries. Although there is a growing number of dementia studies in Latin America, little is known collectively about FTD prevalence studies by country, clinical heterogeneity, risk factors, and genetics in Latin American countries. Methods: A systematic review was completed, aimed at identifying the frequency, clinical heterogeneity, and genetics studies of FTD in Latin American populations. The search strategies used a combination of standardized terms for FTD and related disorders. In addition, at least one author per Latin American country summarized the available literature. Collaborative or regional studies were reviewed during consensus meetings. Results: The first FTD reports published in Latin America were mostly case reports. The last two decades marked a substantial increase in the number of FTD research in Latin American countries. Brazil (165), Argentina (84), Colombia (26), and Chile (23) are the countries with the larger numbers of FTD published studies. Most of the research has focused on clinical and neuropsychological features (n = 247), including the local adaptation of neuropsychological and behavioral assessment batteries. However, there are little to no large studies on prevalence (n = 4), biomarkers (n = 9), or neuropathology (n = 3) of FTD. Conclusions: Future FTD studies will be required in Latin America, albeit with a greater emphasis on clinical diagnosis, genetics, biomarkers, and neuropathological studies. Regional and country-level efforts should seek better estimations of the prevalence, incidence, and economic impact of FTD syndromes.

Interplay between Podoplanin, CD44s and CD44v in Squamous Carcinoma Cells.

Podoplanin and CD44 are transmembrane glycoproteins involved in inflammation and cancer. In this paper, we report that podoplanin is coordinately expressed with the CD44 standard (CD44s) and variant (CD44v) isoforms in vivo-in hyperplastic skin after a pro-inflammatory stimulus with 12-O-tetradecanoylphorbol-13-acetate (TPA)-and in vitro-in cell lines representative of different stages of mouse-skin chemical carcinogenesis, as well as in human squamous carcinoma cell (SCC) lines. Moreover, we identify CD44v10 in the mouse-skin carcinogenesis model as the only CD44 variant isoform expressed in highly aggressive spindle carcinoma cell lines together with CD44s and podoplanin. We also characterized CD44v3-10, CD44v6-10 and CD44v8-10 as the major variant isoforms co-expressed with CD44s and podoplanin in human SCC cell lines. Immunofluorescence confocal microscopy experiments show that these CD44v isoforms colocalize with podoplanin at plasma membrane protrusions and cell-cell contacts of SCC cells, as previously reported for CD44s. Furthermore, CD44v isoforms colocalize with podoplanin in chemically induced mouse-skin SCCs in vivo. Co-immunoprecipitation experiments indicate that podoplanin physically binds to CD44v3-10, CD44v6-10 and CD44v8-10 isoforms, as well as to CD44s. Podoplanin-CD44 interaction is mediated by the transmembrane and cytosolic regions and is negatively modulated by glycosylation of the extracellular domain. These results point to a functional interplay of podoplanin with both CD44v and CD44s isoforms in SCCs and give insight into the regulation of the podoplanin-CD44 association.

New Insights Into the Role of Qa-2 and HLA-G Non-classical MHC-I Complexes in Malignancy.

It is well established that the immune system can identify and destroy neoplastic transformed cells in a process known as immunosurveillance. Most studies have focused on the classical major histocompatibility complex (MHC) class Ia molecules, which are known to play an important role on the presentation of tumor antigens to the immune system in order to activate a response against tumor cells. However, a larger family of non-classical MHC class Ib-related molecules has received less attention. In this mini-review, we discuss the role of class Ib murine Qa-2 and its proposed human HLA-G homolog on immunosurveillance during embryogenesis and cancer. Whereas, both HLA-G and Qa-2 are involved in immune tolerance in pregnancy, the current evidence suggests that they play opposite roles in cancer. HLA-G appears to promote tumor progression while Qa-2 acts as a tumor suppressor awaking the immune system to reject tumor cells, as suggested by studies on different cancer cell models, such as melanoma, lymphoma, lung carcinoma, and our own results in mammary carcinoma.

Reduced expression of the murine HLA-G homolog Qa-2 is associated with malignancy, epithelial-mesenchymal transition and stemness in breast cancer cells.

Qa-2 is believed to mediate a protective immune response against cancer; however, little is known about the role of Qa-2 in tumorigenesis. Here, we used 4T1 breast cancer cells to study the involvement of Qa-2 in tumor progression in a syngeneic host. Qa-2 expression was reduced during in vivo tumor growth and in cell lines derived from 4T1-induced tumors. Tumor-derived cells elicited an epithelial-mesenchymal transition associated with upregulation of Zeb1 and Twist1/2 and enhanced tumor initiating and invasive capacities. Furthermore, these cells showed increased stem characteristics, as demonstrated by upregulation of Hes1, Sox2 and Oct3/4, and enrichment of CD44high/CD24median/low cells. Remarkably, Qa-2 cell-surface expression was excluded from the CD44high/CD24median/low subpopulation. Tumor-derived cells showed increased Src activity, and treatment of these cells with the Src kinase inhibitor PP2 enhanced Qa-2 but reduced Sox2 and CD44high/CD24median/low expression levels, suggesting that Src signaling, while positively associated with stemness, negatively regulates Qa-2 expression in breast cancer. Finally, overexpression of the Qa-2 family member Q7 on the cell surface slowed down in vivo tumor growth and reduced the metastatic potential of 4T1 cells. These results suggest an anti-malignant role for Qa-2 in breast cancer development, which appears to be absent from cancer stem cells.

New insights into the role of podoplanin in epithelial-mesenchymal transition.

Podoplanin is a small mucin-like transmembrane protein expressed in several adult tissues and with an important role during embryogenesis. It is needed for the proper development of kidneys and lungs as well as accurate formation of the lymphatic vascular system. In addition, it is involved in the physiology of the immune system. A wide variety of tumors express podoplanin, both in the malignant cells and in the stroma. Although there are exceptions, the presence of podoplanin results in poor prognosis. The main consequence of forced podoplanin expression in established and tumor-derived cell lines is an increase in cell migration and, eventually, the triggering of an epithelial-mesenchymal transition, whereby cells acquire a fibroblastoid phenotype and increased motility. We will examine the current status of the role of podoplanin in the induction of epithelial-mesenchymal transition as well as the different interactions that lead to this program.