In vitro elimination of epidermal growth factor receptor-overexpressing cancer cells by CD32A-chimeric receptor T cells in combination with cetuximab or panitumumab

Cetuximab and panitumumab bind the human epidermal growth factor receptor (EGFR). Although the chimeric cetuximab (IgG1) triggers antibody-dependent-cellular-cytotoxicity (ADCC) of EGFR positive target cells, panitumumab (a human IgG2) does not. The inability of panitumumab to trigger ADCC reflects the poor binding affinity of human IgG2 Fc for the FcγRIII (CD16) on natural killer (NK) cells. However, both human IgG1 and IgG2 bind the FcγRII (CD32A) to a similar extent. Our study compares the ability of T cells, engineered with a novel low-affinity CD32A^131R-chimeric receptor (CR), and those engineered with the low-affinity CD16^158F-CR T cells, in eliminating EGFR positive epithelial cancer cells (ECCs) in combination with cetuximab or panitumumab. After T-cell transduction, the percentage of CD32A^131R-CR T cells was 74 ± 10%, whereas the percentage of CD16^158F-CR T cells was 46 ± 15%. Only CD32A^131R-CR T cells bound panitumumab. CD32A^131R-CR T cells combined with the mAb 8.26 (anti-CD32) and CD16^158F-CR T cells combined with the mAb 3g8 (anti-CD16) eliminated colorectal carcinoma (CRC), HCT116^FcγR+ cells, in a reverse ADCC assay in vitro. Crosslinking of CD32A^131R-CR on T cells by cetuximab or panitumumab and CD16^158F-CR T cells by cetuximab induced elimination of triple negative breast cancer (TNBC) MDA-MB-468 cells, and the secretion of interferon gamma and tumor necrosis factor alpha. Neither cetuximab nor panitumumab induced Fcγ-CR T antitumor activity against Kirsten rat sarcoma (KRAS)-mutated HCT116, nonsmall-cell-lung-cancer, A549 and TNBC, MDA-MB-231 cells. The ADCC of Fcγ-CR T cells was associated with the overexpression of EGFR on ECCs. In conclusion, CD32A^131R-CR T cells are efficiently redirected by cetuximab or panitumumab against breast cancer cells overexpressing EGFR.     

Locoregional therapy and systemic cetuximab to treat colorectal liver metastases

AIM: To investigate efficacy and safety of second-line treatment with irinotecan-loaded drug-eluting beads (DEBIRI) and cetuximab (DEBIRITUX) of unresectable colorectal liver metastases.METHODS: Patients with the following characteristics were included in the study: unresectable hepatic metastases from colorectal carcinoma (CRC-LM), progression after first line chemotherapy (any type of chemotherapeutic drug and combination was allowed), second line treatment (mandatory), which included for each patient (unregarding the KRas status) two cycles of DEBIRI (using 100-300 μm beads loaded with irinotecan at a total dose 200 mg) followed by 12 cycles of cetuximab that was administered weekly at a first dose of 400 mg/m² and then 250 mg/m²; good performance status (0-2) and liver functionality (alanine aminotransferase and gamma-glutamyl transferase not exceeding three times the upper limit of normal, total bilirubin not exceeding 2.5 mg/mL). Data were collected retrospectively and included: tumor response (evaluated monthly for 6 mo then every 3 mo), overall response rate (ORR), KRas status, type and intensity of adverse events (G according to the Common Terminology Criteria for Adverse Events v3.0, CTCAE), overall survival (OS) and progression free survival (PFS).RESULTS: Forty consecutive cases of CRC hepatic metastases were included in the study. Median duration of DEBIRITUX was 4.4 mo (range, 4.0-6.5). Sixteen patients (40%) received the planned 2 cycles of DEBIRI and an average of 10 cetuximab cycles. ORR of the whole sample was 50%, in particular 4 patients were complete responders (10%) and 16 (40%) partial responders. The most observed side effects (G2) were: post-embolization syndrome (30%), diarrhea (25%), skin rushes (38%) and asthenia (35%). The retrospective evaluation of KRas status (24 wild type, 16 mutated) showed that the group of patients with wild type KRas had ORR significantly higher than mutant KRas. Median follow-up was 29 mo (8-48 range); median PFS was 9.8 mo and OS was 20.4 mo. Future randomized trials are required in this setting to establish a role for DEBIRITUX compared with systemic chemotherapy.CONCLUSION: DEBIRITUX seems to be efficacious after first line chemotherapy for the treatment of unresectable CRC-LM.     

Multimodal imaging for a theranostic approach in a murine model of B-cell lymphoma with engineered nanoparticles

Nanoparticles (NPs) are a promising tool for in vivo multimodality imaging and theranostic applications. Hyaluronic acid (HA)-based NPs have numerous active groups that make them ideal as tumor-targeted carriers. The B-lymphoma neoplastic cells express on their surfaces a clone-specific immunoglobulin receptor (Ig-BCR). The peptide A20-36 (pA20-36) selectively binds to the Ig-BCR of A20 lymphoma cells. In this work, we demonstrated the ability of core-shell chitosan-HA-NPs decorated with pA20-36 to specifically target A20 cells and reduce the tumor burden in a murine xenograft model. We monitored tumor growth using high-frequency ultrasonography and demonstrated targeting specificity and kinetics of the NPs via in vivo fluorescent reflectance imaging. This result was also confirmed by ex vivo magnetic resonance imaging and confocal microscopy. In conclusion, we demonstrated the ability of NPs loaded with fluorescent and paramagnetic tracers to act as multimodal imaging contrast agents and hence as a non-toxic, highly specific theranostic system.     

Liposomes as carriers for dermal delivery of tretinoin: in vitro evaluation of drug permeation and vesicle-skin interaction.

The influence of liposome composition, size, lamellarity and charge on the (trans)dermal delivery of tretinoin (TRA) was studied. For this purpose we studied both multilamellar (MLV) or unilamellar (UV) liposomes. Positively or negatively charged liposomes were obtained using either hydrogenated (Phospholipon90H) or non-hydrogenated soy phosphatidylcholine (Phospholipon90) and cholesterol, in combination with stearylamine or dicetylphosphate. Liposomal formulations were characterized by transmission electron microscopy (TEM) and optical and light polarized microscopy for vesicle formation and morphology, and by dynamic laser light scattering for size distribution. In order to obtain more information about the stability and the thermodynamic activity of the liposomal tretinoin, TRA diffusion through a lipophilic membrane was investigated. The effect of the vesicular incorporation of tretinoin on its accumulation into the newborn pig skin was also studied. The experiments were performed in vitro using Franz cells in occlusive conditions and were compared to three different controls. The tretinoin amount delivered through and accumulated in the several skin layers was detected by HPLC. Furthermore, TEM in combination with osmium tetroxide was used to visualize the skin structure after the liposomal administration. Overall obtained results showed that liposomes may be an interesting carrier for tretinoin in skin disease treatment, when appropriate formulations are used. In particular, negatively charged liposomes strongly improved newborn pig skin hydration and TRA retention, though no evidence of intact vesicle penetration was found.     

Easier Said Than Done: The Challenge to Teach “Personal Recovery” to Mental Health Professionals Through a Short,Targeted and Structured Training Programme

This study assesses the effectiveness of our short Personal Recovery Training Program (PRTP) for mental health professionals. Fifty-two healthcare professionals from Italian mental health services and forty students in psychiatric rehabilitation completed the Recovery Knowledge Inventory (RKI) pre- and post-training, divided into two groups: the PRTP (N?=?45) and the Family Psychoeducational Training Program (FPTP; N?=?47). Participants’ understanding of personal recovery improved more significantly for those in the PRTP than for those in the FPTP group in two domains, “Roles and responsibilities” and “Non-linearity of the recovery process”; the FPTP group showed a significant improvement in the “Role of self-definition and peers in recovery” domain. Two consumers were involved in the PRTP and represented a resource to help participants understand the personal recovery process. Our findings indicate that a brief PRTP supported by consumers can improve staff and students' recovery orientation. The translation of the training into clinical practice remains unevaluated.

     

Dichloroacetate,a selective mitochondria-targeting drug for oral squamous cell carcinoma: a metabolic perspective of treatment

Reprogramming of metabolism is a well-established property of cancer cells that is receiving growing attention as potential therapeutic target. Oral squamous cell carcinomas (OSCC) are aggressive and drugs-resistant human tumours displaying wide metabolic heterogeneity depending on their malignant genotype and stage of development. Dichloroacetate (DCA) is a specific inhibitor of the PDH-regulator PDK proved to foster mitochondrial oxidation of pyruvate. In this study we tested comparatively the effects of DCA on three different OSCC-derived cell lines, HSC-2, HSC-3, PE15. Characterization of the three cell lines unveiled for HSC-2 and HSC-3 a glycolysis-reliant metabolism whereas PE15 accomplished an efficient mitochondrial oxidative phosphorylation. DCA treatment of the three OSCC cell lines, at pharmacological concentrations, resulted in stimulation of the respiratory activity and caused a remarkably distinctive pro-apoptotic/cytostatic effect on HSC-2 and HSC-3. This was accompanied with a large remodeling of the mitochondrial network, never documented before, leading to organelle fragmentation and with enhanced production of reactive oxygen species. The data here presented indicate that the therapeutic efficacy of DCA may depend on the specific metabolic profile adopted by the cancer cells with those exhibiting a deficient mitochondrial oxidative phosphorylation resulting more sensitive to the drug treatment.     

GPER agonist G-1 decreases adrenocortical carcinoma (ACC) cell growth in vitro and in vivo

We have previously demonstrated that estrogen receptor (ER) alpha (ESR1) increases proliferation of adrenocortical carcinoma (ACC) through both an estrogen-dependent and -independent (induced by IGF-II/IGF1R pathways) manner. Then, the use of tamoxifen, a selective estrogen receptor modulator (SERM), appears effective in reducing ACC growth in vitro and in vivo. However, tamoxifen not only exerts antiestrogenic activity, but also acts as full agonist on the G protein-coupled estrogen receptor (GPER). Aim of this study was to investigate the effect of a non-steroidal GPER agonist G-1 in modulating ACC cell growth. We found that G-1 is able to exert a growth inhibitory effect on H295R cells both in vitro and, as xenograft model, in vivo. Treatment of H295R cells with G-1 induced cell cycle arrest, DNA damage and cell death by the activation of the intrinsic apoptotic mechanism. These events required sustained extracellular regulated kinase (ERK) 1/2 activation. Silencing of GPER by a specific shRNA partially reversed G-1-mediated cell growth inhibition without affecting ERK activation. These data suggest the existence of G-1 activated but GPER-independent effects that remain to be clarified. In conclusion, this study provides a rational to further study G-1 mechanism of action in order to include this drug as a treatment option to the limited therapy of ACC.