Targeting hyaluronan metabolism-related molecules associated with resistant tumor-initiating cells potentiates chemotherapy efficacy in lung cancer.

The success of chemotherapy regimens in patients with non-small cell lung cancer (NSCLC) could be restricted at least in part by cancer stem cells (CSC) niches within the tumor microenvironment (TME). CSC express CD133, CD44, CD47, and SOX2, among other markers and factors. Analysis of public data revealed that high expression of hyaluronan (HA), the main glycosaminoglycan of TME, correlated positively with CSC phenotype and decreased disease-free interval in NSCLC patients. We aimed to cross-validate these findings on human and murine lung cancer cells and observed that CD133 + CSC differentially expressed higher levels of HA, HAS3, ABCC5, SOX2, and CD47 (p < 0.01). We modulated HA expression with 4-methylumbelliferone (4Mu) and detected an increase in sensitivity to paclitaxel (Pa). We evaluated the effect of 4Mu + chemotherapy on survival, HA metabolism, and CSC profile. The combination of 4Mu with Pa reduced the clonogenic and tumor-forming ability of CSC. Pa-induced HAS3, ABCC5, SOX2, and CD47 expression was mitigated by 4Mu. Pa + 4Mu combination significantly reduced in vivo tumor growth, enhancing animal survival and restoring the CSC profile in the TME to basal levels. Our results suggest that HA is involved in lung CSC phenotype and chemosensitivity, and its modulation by 4Mu improves treatment efficacy to inhibit tumor progression.

Detection of NTRK gene fusions in solid tumors: recommendations from a Latin American group of oncologists and pathologists.

NTRK gene fusions have been detected in more than 25 types of tumors and their prevalence is approximately 0.3% in solid tumors. This low prevalence makes identifying patients who could benefit from TRK inhibitors a considerable challenge. Furthermore, while numerous papers on the evaluation of NTRK fusion genes are available, not all countries have guidelines that are suitable for their setting, as is the case with Latin America. Therefore, a group of oncologists and pathologists from several countries in Latin America (Argentina, Chile, Ecuador, Mexico, Peru and Uruguay) met to discuss and reach consensus on how to identify patients with NTRK gene fusions in solid tumors. To do so, they developed a practical algorithm, considering their specific situation and limitations.

Optimal Therapeutic Strategy for PD-L1 Negative Metastatic Non-Small Cell Lung Cancer: A Decision-Making Guide Based on Clinicopathological and Molecular Features.

OPINION STATEMENT: Strategies using immune checkpoint inhibitors (ICI), which can enhance antitumor immune responses, have revolutionized the lung cancer therapeutic landscape. The ICI mechanism of action involves the blockade of regulatory cell surface molecules using antibodies against the Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) (ipilimumab, tremelimumab); the programmed death receptor-1 (PD-1; nivolumab, pembrolizumab); or the PD ligand-1 (PD-L1; atezolizumab, durvalumab). Notably, anti-PD-1 demonstrated long-term survival benefits, durable objective responses, and a manageable safety profile in patients with non-small cell lung cancer (NSCLC). The combination of anti-PD1 or anti-PD-L1 and platinum chemotherapy achieved better survival outcomes than chemotherapy alone, which was observed irrespective of PD-L1 expression on cancer cells. Although promising results have been reported from large clinical trials, especially for patients with high PD-L1 expression, the optimal treatment approach for patients with PD-L1-negative NSCLC has yet to be defined. We propose a guide for clinicians in the therapeutic decision-making process based on the latest data available about treatments, prognostic factors, predictive biomarkers, and real-world evidence in PD-L1-negative NSCLC patients.

Phenotypic and functional analysis in HER2+ targeted therapy of human NK cell subpopulation according to the expression of FcεRIγ and NKG2C in breast cancer patients.

Adaptive NK cells constitute an NK cell subpopulation, which expands after human cytomegalovirus (HCMV) infection. This subpopulation has stronger production of cytokines after CD16 stimulation, longer life and persistence than conventional NK cells and are, therefore, interesting tools for cancer immunotherapy. Since there is limited information on adaptive NK cells in cancer patients, we described this population phenotypically and functionally, by flow cytometry, in the context of HER2 + breast cancer (BC) directed therapy. We assessed HCMV status in 78 patients with BC. We found that, similarly to healthy donors (HD), a high proportion of BC patients were HCMV-positive, and nearly 72% of them had an adaptive NK cell subpopulation characterized by the loss of FcεRIγ intracellular adaptor protein or the presence of NKG2C receptor. However, in BC patients, FcεRIγ- and NKG2C + NK cell populations overlapped to a lesser extent than in HD. Otherwise, no profound phenotypic differences were found between BC patients and HD. Although FcεRIγ- or NKG2C + NK cell subsets from BC patients produced more IFN-γ than their FcεRIγ + or NKG2C- NK cell counterparts, IFN-γ production increased only when NK cells simultaneously expressed FcεRIγ- and NKG2C + , whereas in HD the presence of NKG2C marker was sufficient to display greater functionality. Furthermore, in a group of patients treated with chemotherapy and Trastuzumab plus Pertuzumab, FcεRIγ-NKG2C + and FcεRIγ-NKG2C- NK cells retained greater functionality after treatment than FcεRIγ + NKG2C- NK cells. These results suggest that the presence or magnitude of adaptive NK cell subsets might serve as a key determinant for therapeutic approaches based on antibodies directed against tumor antigens.

Targeting ADCC: A different approach to HER2 breast cancer in the immunotherapy era.

The clinical outcome of patients with human epidermal growth factor receptor 2 (HER2) amplified breast carcinoma (BC) has improved with the development of anti-HER2 targeted therapies. However, patients can experience disease recurrence after curative intent and disease progression in the metastatic setting. In the current era of evolving immunotherapy agents, the understanding of the immune response against HER2 tumor cells developed by anti-HER2 antibodies (Abs) is rapidly evolving. Trastuzumab therapy promotes Natural Killer (NK) cell activation in patients with BC overexpressing HER2, indicating that the efficacy of short-term trastuzumab monotherapy, albeit direct inhibition of HER, could also be related with antibody-dependent cell-mediated cytotoxicity (ADCC). Currently, dual HER2 blockade using trastuzumab and pertuzumab is the standard of care in early and advanced disease as this combination could confer an additive effect in ADCC. In patients with disease relapse or progression, ADCC may be hampered by several factors such as FcγRIIIa polymorphism and an immunosuppressive environment, among others. Hence, new drug development strategies are being investigated aiming to boost the ADCC response triggered by anti-HER2 therapy. In this review, we summarize these strategies and the rationale, through mAbs engineering and combinatorial strategies, focusing on clinical results and ongoing trials.

Pulsing dendritic cells with whole tumor cell lysates.

One of the strategies employed in immunotherapy for cancer is to use of ex vivo-generated dendritic cells (DC) pulsed with tumor antigens. Several approaches have been used to obtain and load tumor antigens in DC. One such technique is to use whole tumor cell lysate from one or more tumor cell lines of the tumor type to be treated. The advantage of applying this method is that it provides a large spectrum of tumor antigens. However, some considerations must be taken into account to obtain a lysate with appropriate biological activity, such as cell line harvest and the method to lyse the cells. In this chapter, we describe the steps to obtain whole tumor cell lysates from human tumor cell lines by repetitive freeze-thaw cycles in sufficient amount and quality to pulse DC.

Ex vivo loading of autologous dendritic cells with tumor antigens.

Ex vivo-generated antigen-loaded dendritic cells (DC) have been shown to be immunogenic in patients with cancer. Loading DC with autologous whole tumor antigens is a strategy to arm DC against tumor without human leukocyte antigen (HLA) restriction. Furthermore, this approach allows the presentation of a full antigen range to the immune system. We describe the methods to obtain whole antigens from autologous tumor tissues in order to load DC generated ex vivo from patients with gastrointestinal cancer.

Integración de marcadores humorales, ecocardiograma Doppler convencional y strain bidimensional sistólico en la detección de toxicidad miocárdica secundaria a la quimioterapia / Serum Markers, Conventional Doppler Echocardiography and Two-dimensional Systolic Strain in the Diagnosis of Chemotherapy-Induced Myocardial Toxicity

Introducción La disfunción ventricular izquierda es una complicación grave del tratamiento antineoplásico, con impacto desfavorable en la evolución clínica futura. El diagnóstico precoz de cardiotoxici-dad en pacientes que reciben quimioterapia podría ser de utilidad para definir una estrategia de prevención del deterioro de la función ventricular. Objetivo Analizar la utilidad de marcadores humorales [troponina T (TnT), BNP y NT-proBNP] y del strain bidimensional sistólico longitudinal (SBL) y radial (SBR) para la detección de disfunción ventricular sistólica en pacientes tratados con quimioterapia cardiotóxica. Material y métodos Se incluyeron forma prospectiva 36 pacientes, edad promedio (± DE) de 47 ± 16 años (42% hombres), con enfermedad neoplásica con masa miocárdica normal y fracción de eyección = 55% tratados con agentes antineoplásicos. Se efectuaron dosajes de marcadores humorales y ecocardiograma basales y al 2°, 3°, 4° y 6° mes posterior al inicio del tratamiento oncológico. Se consideró punto final (PF) a los 6 meses a la caída de la fracción de eyección según consenso internacional. Resultados Alcanzaron el PF 7 pacientes (19,4%). Se observaron los siguientes predictores relacionados con el PF: NT-proBNP 4° mes [PF positivo (G1) 152 ± 42 pg/ml vs. PF negativo (G2) 61 ± 38 pg/ml; p < 0,001], BNP 4° mes (G1 41 ± 12 pg/ml vs. G2 26 ± 11 pg/ml; p < 0,01), SBL 3er mes (G1 -16,3 ± 2,4% vs. G2 -19,6 ± 2,02%; p < 0,01) y 4° mes (G1 -15,9 ± 1,77% vs. G2 -19,9 ± 2,2%; p < 0,001) y SBR 4° mes (G1 46,4 ± 2,4% vs. G2 52 ± 3,4%; p < 0,001). Conclusiones El dosaje de péptidos natriuréticos y la medición del strain bidimensional sistólico longitudinal y radial fueron de utilidad para predecir disfunción sistólica ventricular de grado leve en pacientes tratados con quimioterapia.

Background Left ventricular dysfunction is a serious complication of antineoplastic treatment with unfavorable impact in future clinical outcome. Early diagnosis of cardiotoxicity in patients receiving chemotherapy might be useful to define a strategy for the prevention of ventricular function impairment. Objective The aim of this study was to analyze the usefulness of serum markers [troponin T (TnT), BNP and NT-proBNP] and two-dimensional longitudinal (LS) and radial (RS) strain to detect ventricular systolic dysfunction in patients treated with cardiotoxic chemotherapy. Methods Thirty six patients [average age (±SD) 47±16 years, 42% men], with neoplastic disease with normal myocardial mass and left ventricular ejection fraction (LVEF) =55% receiving chemotherapy treatment, were prospectively included. Assessment of serum markers and echocardiography were performed before chemotherapy and at 2, 3, 4 and 6 months after onset of cancer treatment. The 6-month cardiotoxicity endpoint (EP) was defined as reduced LVEF according to international consensus. Results Seven patients reached the EP (19.4%). Endpoint predictors were: NT-proBNP at 4 months (positive EP (G1): 152 ±42 pg/ml vs. negative EP (G2) 61±38 pg/ml; p <0.001), BNP at 4 months (G1 41±12 pg/ml vs. G2 26±11 pg/ml; p <0.01), two-dimensional LS at 3 months (G1 -16.3±2.4% vs. G2 19.6±2.02%; p <0.01) and 4 months (G1 -15.9±1.77% vs. G2 19.9±2.2%; p <0.001), and two-dimensional RS at 4 months (G1 46.4±2.4% vs. G2 52±3.4%; p <0.001). Conclusions Natriuretic peptides and two-dimensional LS and RS were useful to predict mild ventricular systolic dysfunction in chemotherapy-treated patients.

Antitumor effects of hyaluronic acid inhibitor 4-methylumbelliferone in an orthotopic hepatocellular carcinoma model in mice.

Liver cirrhosis is characterized by an excessive accumulation of extracellular matrix components, including hyaluronan (HA). In addition, cirrhosis is considered a pre-neoplastic disease for hepatocellular carcinoma (HCC). Altered HA biosynthesis is associated with cancer progression but its role in HCC is unknown. 4-Methylumbelliferone (4-MU), an orally available agent, is an HA synthesis inhibitor with anticancer properties. In this work, we used an orthotopic Hepa129 HCC model established in fibrotic livers induced by thioacetamide. We evaluated 4-MU effects on HCC cells and hepatic stellate cells (HSCs) in vitro by proliferation, apoptosis and cytotoxicity assays; tumor growth and fibrogenesis were also analyzed in vivo. Our results showed that treatment of HCC cells with 4-MU significantly reduced tumor cell proliferation and induced apoptosis, while primary cultured hepatocytes remained unaffected. 4-MU therapy reduced hepatic and systemic levels of HA. Tumors systemically treated with 4-MU showed the extensive areas of necrosis, inflammatory infiltrate and 2-3-fold reduced number of tumor satellites. No signs of toxicity were observed after 4-MU therapy. Animals treated with 4-MU developed a reduced fibrosis degree compared with controls (F1-2 vs F2-3, respectively). Importantly, 4-MU induced the apoptosis of HSCs in vitro and decreased the amount of activated HSCs in vivo. In conclusion, our results suggest a role for 4-MU as an anticancer agent for HCC associated with advanced fibrosis.

Hepatocellular carcinoma cells and their fibrotic microenvironment modulate bone marrow-derived mesenchymal stromal cell migration in vitro and in vivo.

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third cause of cancer-related death. Fibrogenesis is an active process characterized by the production of several proinflammatory cytokines, chemokines and growth factors. It involves the activation of hepatic stellate cells (HSCs) which accumulate at the site of injury and are the main source of the extracellular matrix deposits. There are no curative treatments for advanced HCC, thus, new therapies are urgently needed. Mesenchymal stromal cells (MSCs) have the ability to migrate to sites of injury or to remodeling tissues after in vivo administration; however, in several cancer models they demonstrated limited efficacy to eradicate experimental tumors partially due to poor engraftment. Thus, the aim of this work was to analyze the capacity of human MSCs (hMSCs) to migrate and anchor to HCC tumors. We observed that HCC and HSCs, but not nontumoral stroma, produce factors that induce hMSC migration in vitro. Conditioned media (CM) generated from established HCC cell lines were found to induce higher levels of hMSC migration than CM derived from fresh patient tumor samples. In addition, after exposure to CM from HCC cells or HSCs, hMSCs demonstrated adhesion and invasion capability to endothelial cells, type IV collagen and fibrinogen. Consistently, these cells were found to increase metalloproteinase-2 activity. In vivo studies with subcutaneous and orthotopic HCC models indicated that intravenously infused hMSCs migrated to lungs, spleen and liver. Seven days post-hMSC infusion cells were located also in the tumor in both models, but the signal intensity was significantly higher in orthotopic than in subcutaneous model. Interestingly, when orthotopic HCC tumors where established in noncirrhotic or cirrhotic livers, the amount of hMSCs localized in the liver was higher in comparison with healthy animals. A very low signal was found in lungs and spleens, indicating that liver tumors are able to recruit them at high efficiency. Taken together our results indicate that HCC and HSC cells produce factors that efficiently induce hMSC migration toward tumor microenvironment in vitro and in vivo and make MSCs candidates for cell-based therapeutic strategies to hepatocellular carcinoma associated with fibrosis.

Suramab, a novel antiangiogenic agent, reduces tumor growth and corneal neovascularization.

PURPOSE: Oncological and ophthalmological diseases are increasingly treated with antiangiogenic agents. These agents have different intensities and duration of effects that should be considered to choose the most suitable therapy. Our purpose was to evaluate the synergistic effect of two drugs, jointly administered as a pharmaceutical compound, in two animal models. METHODS: Corneal neovascularization was induced in three groups of nine white New Zealand rabbits, applying a filter paper disk soaked in 1 M NaOH on the central cornea (Ormerod et al., Invest Ophthalmol Vis Sci 30:2148-2153, 1989). Group one was treated immediately after injury with intravenous Suramab, compound of Bevacizumab + Suramin, and group two with intravenous Bevacizumab. A third group of non-treated rabbits was included as control group. Digital photographs were taken at days 9, 15, 21, and 35. Neovessel index (NVI) was calculated using the Image J Program. Neovessels formation was quantified and given a score from 0 to 4 to each quadrant according to the centripetal growth of the longest vessel. Colorectal animal model: 6- to 8-week-old male BALB/c mice were inoculated with cancer cells. Seven days after tumor inoculation, four groups of BALB/c mice were treated with intravenous Bevacizumab (n = 9); intravenous Suramin (n = 10); intravenous Suramab (n = 10); and intravenous saline solution (n = 4). Tumor growth was assessed twice weekly by caliper measurement. RESULTS: The NVI was remarkably inferior in the group of rabbits treated with intravenous Suramab compared with controls after 35 days of follow-up. A greater inhibitory effect was obtained with Suramab compared to that obtained with Bevacizumab. Suramab significantly reduced tumor volume and prolonged survival of mice compared to controls. CONCLUSIONS: Suramab strongly reduced neovascularization in a rabbit model of corneal angiogenesis and induced a potent antitumoral effect in mice.