Vγ9Vδ2 T-cells are potent inhibitors of SARS-CoV-2 replication and represent effector phenotypes in COVID-19 patients.

Vγ9Vδ2 T-cells play a key role in the innate immune response to viral infections through butyrophilin (BTN)-3A. Here, we reported that blood Vγ9Vδ2 T-cells decreased in clinically mild COVID-19 compared to healthy volunteers (HV), and was maintained up to 28-days and in the recovery period. Terminally differentiated Vγ9Vδ2 T-cells tend to be enriched on the day of diagnosis, 28-days after and during the recovery period. These cells showed cytotoxic and inflammatory activities following anti-BTN3A activation. BTN3A upregulation and Vγ9Vδ2 T-cell infiltration were observed in a lung biopsy from a fatal SARS-CoV-2 infection. In vitro, SARS-CoV-2 infection increased BTN3A expression in macrophages and lung cells that enhanced the anti-SARS-CoV-2 Vγ9Vδ2 T-cells cytotoxicity and IFNγ and TNFα. Increasing concentrations of anti-BTN3A lead to viral replication inhibition. Altogether, we report that Vγ9Vδ2 T-cells are important in the immune response against SARS-CoV-2 infection and that activation by an anti-BTN3A antibody may enhance their response.

Major pathways involved in macrophage polarization in cancer.

Macrophages play an important role in tissue homeostasis, tissue remodeling, immune response, and progression of cancer. Consequently, macrophages exhibit significant plasticity and change their transcriptional profile and function in response to environmental, tissue, and inflammatory stimuli resulting in pro- and anti-tumor effects. Furthermore, the categorization of tissue macrophages in inflammatory situations remains difficult; however, there is an agreement that macrophages are predominantly polarized into two different subtypes with pro- and anti-inflammatory properties, the so-called M1-like and M2-like macrophages, respectively. These two macrophage classes can be considered as the extreme borders of a continuum of many intermediate subsets. On one end, M1 are pro-inflammatory macrophages that initiate an immunological response, damage tissue integrity, and dampen tumor progression by fostering robust T and natural killer (NK) cell anti-tumoral responses. On the other end, M2 are anti-inflammatory macrophages involved in tissue remodeling and tumor growth, that promote cancer cell proliferation, invasion, tumor metastasis, angiogenesis and that participate to immune suppression. These decisive roles in tumor progression occur through the secretion of cytokines, chemokines, growth factors, and matrix metalloproteases, as well as by the expression of immune checkpoint receptors in the case of M2 macrophages. Moreover, macrophage plasticity is supported by stimuli from the Tumor Microenvironment (TME) that are relayed to the nucleus through membrane receptors and signaling pathways that result in gene expression reprogramming in macrophages, thus giving rise to different macrophage polarization outcomes. In this review, we will focus on the main signaling pathways involved in macrophage polarization that are activated upon ligand-receptor recognition and in the presence of other immunomodulatory molecules in cancer.

BTN3A Targeting Vγ9Vδ2 T Cells Antimicrobial Activity Against Coxiella burnetii-Infected Cells.

Vγ9Vδ2 T cells have been reported to participate to the immune response against infectious diseases such as the Q fever caused by Coxiella burnetii infection. Indeed, the number and proportion of Vγ9Vδ2 T cells are increased during the acute phase of Q fever. Human Vγ9Vδ2 T cell responses are triggered by phosphoantigens (pAgs) produced by pathogens and malignant cells, that are sensed via the membrane receptors butyrophilin-3A1 (BTN3A1) and -2A1 (BTN2A1). Here, by using CRISPR-Cas9 inactivation in THP-1 cells, we show that BTN3A and BTN2A are required to Vγ9Vδ2 T cell response to C. burnetii infection, though not directly involved in the infection process. Furthermore, C. burnetii-infected monocytes display increased BTN3A and BTN2A expression and induce Vγ9Vδ2 T cell activation that can be inhibited by specific antagonist mAb. More importantly, we show that the antimicrobial functions of Vγ9Vδ2 T cells towards C. burnetii are enhanced in the presence of an BTN3A activating antibody. This supports the role of Vγ9Vδ2 T cells in the control of C. burnetii infection and argues in favor of targeting these cells as an alternative treatment strategy for infectious diseases caused by intracellular bacteria.

Development of ICT01, a first-in-class, anti-BTN3A antibody for activating Vγ9Vδ2 T cell-mediated antitumor immune response.

Gamma delta T (γδ T) cells are among the most potent cytotoxic lymphocytes. Activating anti­butyrophilin 3A (BTN3A) antibodies prime diverse tumor cell types to be killed by Vγ9Vδ2 T cells, the predominant γδ T cell subset in peripheral circulation, by mechanisms independent of tumor antigen­major histocompatibility complex (MHC) complexes. In this report, we describe the development of a humanized monoclonal antibody, ICT01, with subnanomolar affinity for the three isoforms of BTN3A. We demonstrate that ICT01-activated Vγ9Vδ2 T cells kill multiple tumor cell lines and primary tumor cells, but not normal healthy cells, in an efficient process requiring approximately 20% target occupancy. We show that ICT01 activity is dependent on BTN3A and BTN2A but independent of the phosphoantigen (pAg)­binding B30.2 domain. ICT01 delays the growth of hematologic and solid tumor xenografts and prolongs survival of NOD/SCID/IL2rγnull (NSG) mice adoptively transferred with human Vγ9Vδ2 T cells. In single- and multiple-dose safety studies in cynomolgus macaques that received up to 100 mg/kg once weekly, ICT01 was well tolerated. With respect to pharmacodynamic endpoints, ICT01 selectively activated Vγ9Vδ2 T cells without affecting other BTN3A-expressing lymphocytes such as αß T or B cells. A first-in-human, phase 1/2a, open-label, clinical study of ICT01 was thus initiated in patients with advanced-stage solid tumors (EVICTION: NCT04243499; EudraCT: 2019-003847-31). Preliminary results show that ICT01 was well tolerated and pharmacodynamically active in the first patients. Digital pathology analysis of tumor biopsies of a patient with melanoma suggests that ICT01 may promote immune cell infiltration within the tumor microenvironment.

Human γδ T cell sensing of AMPK-dependent metabolic tumor reprogramming through TCR recognition of EphA2.

Human γδ T cells contribute to tissue homeostasis and participate in epithelial stress surveillance through mechanisms that are not well understood. Here, we identified ephrin type-A receptor 2 (EphA2) as a stress antigen recognized by a human Vγ9Vδ1 TCR. EphA2 is recognized coordinately by ephrin A to enable γδ TCR activation. We identified a putative TCR binding site on the ligand-binding domain of EphA2 that was distinct from the ephrin A binding site. Expression of EphA2 was up-regulated upon AMP-activated protein kinase (AMPK)-dependent metabolic reprogramming of cancer cells, and coexpression of EphA2 and active AMPK in tumors was associated with higher CD3 T cell infiltration in human colorectal cancer tissue. These results highlight the potential of the human γδ TCR to cooperate with a co-receptor to recognize non-MHC-encoded proteins as signals of cellular dysregulation, potentially allowing γδ T cells to sense metabolic energy changes associated with either viral infection or cancer.

BTN2A1, an immune checkpoint targeting Vγ9Vδ2 T cell cytotoxicity against malignant cells.

The anti-tumor response of Vγ9Vδ2 T cells requires the sensing of accumulated phosphoantigens (pAgs) bound intracellularly to butyrophilin 3A1 (BTN3A1). In this study, we show that butyrophilin 2A1 (BTN2A1) is required for BTN3A-mediated Vγ9Vδ2 T cell cytotoxicity against cancer cells, and that expression of the BTN2A1/BTN3A1 complex is sufficient to trigger Vγ9Vδ2 TCR activation. Also, BTN2A1 interacts with all isoforms of BTN3A (BTN3A1, BTN3A2, BTN3A3), which appears to be a rate-limiting factor to BTN2A1 export to the plasma membrane. BTN2A1/BTN3A1 interaction is enhanced by pAgs and, strikingly, B30.2 domains of both proteins are required for pAg responsiveness. BTN2A1 expression in cancer cells correlates with bisphosphonate-induced Vγ9Vδ2 T cell cytotoxicity. Vγ9Vδ2 T cell killing of cancer cells is modulated by anti-BTN2A1 monoclonal antibodies (mAbs), whose action relies on the inhibition of BTN2A1 binding to the Vγ9Vδ2TCR. This demonstrates the potential of BTN2A1 as a therapeutic target and adds to the emerging butyrophilin-family cooperation pathway in γδ T cell activation.

Risk factors associated with overweight and obesity in HIV-infected people: Aging, behavioral factors but not cART in a cross-sectional study.

Identifying risk factors associated with overweight and obesity in HIV-infected patients.A cross-sectional study analyzing data from patients attending an HIV outpatient unit. Overweight was defined as body mass index (BMI) ≥25 kg/m; <30 kg/m, obesity was ≥30 kg/m. Patients' characteristics contemporary to BMI assessment were collected. Multivariate logistic regression identified risk factors associated with overweight/obesity.Eight hundred sixty-two patients, median age 51 years, 21.5 years of HIV infection follow-up, 585 (68%) male, 829 (96%) receiving combined antiretroviral therapy (cART) for median 16.7 years, 768 (91%) HIV load <40 copies/mL, 618 (73%) CD4 ≥500 cells/mm; 266 (31%) HCV serology, 110 (13%) had detectable HCV-RNA. Overweight affected 191 (22%) patients and obesity 46 (5%). Overweight and obesity were associated with age, HIV follow-up duration, and HIV transmission risk group. Overweight was also associated with gender and HCV status. In patients with substance use data, overweight was associated with alcohol and nonsmoking status. Obesity was associated with nonsmoking and ex-smoker status. Overweight/obesity were not found associated with cART or immune cell counts.In HIV-infected people, aging, alcohol consumption, nonsmoking, and ex-smoker status, the absence of HCV coinfection and to have cleared HCV infection are associated with overweight and/or obesity. Clinicians should be aware of these trends and consider introducing weight management programs as part of routine HIV care.

Frailty in HIV infected people: a new risk factor for bone mineral density loss.

OBJECTIVE: The study aims to assess the association between bone mineral density (BMD) and frailty in a cohort of HIV-infected patients. DESIGN: A cross-sectional study in an HIV outpatient unit where nearly 1000 patients are monitored. METHODS: Study participants undergoing bone densitometry were proposed an evaluation of frailty using criteria of the Cardiovascular Health Study (CHS) and the Study of Osteoporotic Fractures (SOF). Frailty markers were weight-loss, self-reported exhaustion, physical activity, grip strength, chair stands, and slow gait. Patients' characteristics were collected from an electronic medical record. Associations of frailty with BMD and osteoporosis were tested using multivariate linear and logit regression models, respectively. RESULTS: In total, 175 HIV-infected patients, 121 (69.14%) men, were analyzed. Prevalence of frailty markers, osteopenia, and osteoporosis were comparable among sexes. Despite a younger age, spinal and femoral neck BMD were lower in women (P < 0.05). Linear regression model adjusting by age, duration of HIV follow-up, BMI, smoking status, osteoarthritis, osteoporosis treatment, and the age at menopause showed a negative association of spinal and femoral BMD with frailty according to SOF criteria in women (P < 0.05). In men, SOF-defined frailty was associated with osteoporosis (odds ratio 28.79; 95% confidence interval 2.15-386.4) in a model adjusting for age, duration of HIV follow-up, CD4 nadir, CD4 T-cell count, tobacco consumption, exposure to tenofovir (TDF) and protease inhibitors. No significant associations were found between BMD and CHS-defined frailty. CONCLUSION: Our study shows that frailty according to SOF criteria is associated with low spinal BMD values in female and osteoporosis in male HIV-infected patients.

Pancreatitis promotes oncogenic Kras(G12D)-induced pancreatic transformation through activation of Nupr1.

During the initiation stage of pancreatic adenocarcinoma induced by oncogenic Kras, pancreatic cells are exposed to both a protumoral effect and an opposing tumor suppressive process known as oncogene-induced senescence. Pancreatitis disrupts this balance in favor of the transforming effect of oncogenes by lowering the tumor suppressive threshold of oncogene-induced senescence through expression of the stress protein Nupr1.

Genetic inactivation of Nupr1 acts as a dominant suppressor event in a two-hit model of pancreatic carcinogenesis.

BACKGROUND: Nuclear protein 1 (Nupr1) is a major factor in the cell stress response required for Kras(G12D)-driven formation of pancreatic intraepithelial neoplastic lesions (PanINs). We evaluated the relevance of Nupr1 in the development of pancreatic cancer. METHODS: We investigated the role of Nupr1 in pancreatic ductal adenocarcinoma (PDAC) progression beyond PanINs in Pdx1-cre;LSL-Kras(G12D);Ink4a/Arf(fl/fl)(KIC) mice. RESULTS: Even in the context of the second tumorigenic hit of Ink4a/Arf deletion, Nupr1 deficiency led to suppression of malignant transformation involving caspase 3 activation in premalignant cells of KIC pancreas. Only half of Nupr1-deficient;KIC mice achieved PDAC development, and incident cases survived longer than Nupr1(wt);KIC mice. This was associated with the development of well-differentiated PDACs in Nupr1-deficient;KIC mice, which displayed enrichment of genes characteristic of the recently identified human classical PDAC subtype. Nupr1-deficient;KIC PDACs also shared with human classical PDACs the overexpression of the Kras-activation gene signature. In contrast, Nupr1(wt);KIC mice developed invasive PDACs with enriched gene signature of human quasi-mesenchymal (QM) PDACs. Cells derived from Nupr1-deficient;KIC PDACs growth in an anchorage-independent manner in vitro had higher aldehyde dehydrogenase activity and overexpressed nanog, Oct-4 and Sox2 transcripts compared with Nupr1(wt);KIC cells. Moreover, Nupr1-deficient and Nurpr1(wt);KIC cells differed in their sensitivity to the nucleoside analogues Ly101-4b and WJQ63. Together, these findings show the pivotal role of Nupr1 in both the initiation and late stages of PDAC in vivo, with a potential impact on PDAC cell stemness. CONCLUSIONS: According to Nupr1 status, KIC mice develop tumours that phenocopy human classical or QM-PDAC, respectively, and present differential drug sensitivity, thus becoming attractive models for preclinical drug trials.

NUPR1 works against the metabolic stress-induced autophagy-associated cell death in pancreatic cancer cells.

The incidence of pancreatic adenocarcinoma is increasing with more than 43,000 predicted new cases in the US and 65,000 in Europe this year. Pancreatic cancer patients have a short life expectancy with less than 3-4% 5-y survival, which results in an equivalent incidence and mortality rate. One of the major challenges in pancreatic cancer is the identification of pharmacological approaches that overcome the resistance of this cancer to therapy. Intensive research in the past decades has led to the classification of pancreatic cancers and the identification of the driver key genetic events. Despite the advances in understanding the molecular mechanisms responsible for pancreatic cancer pathogenesis, this knowledge had little impact on significantly improving the treatment for this dismal disease. In particular, we know today that the lack of therapeutic response in pancreatic cancer is due to the intrinsic high resistance of these tumors to chemotherapy and radiation, rather than to the inappropriate design of these therapeutic approaches. Thus, in order to ensure a better outcome for pancreatic cancer patients, there is a strong need for research focused on the mechanism that determines this resistant phenotype and the means that might drive enhanced response to therapy.

Nupr1-aurora kinase A pathway provides protection against metabolic stress-mediated autophagic-associated cell death.

PURPOSE: The limited supply of oxygen and nutrients is thought to result in rigorous selection of cells that will eventually form the tumor. EXPERIMENTAL DESIGN: Nupr1 expression pattern was analyzed in human tissue microarray (TMA) and correlated with survival time of the patient. Microarray analysis was conducted on MiaPaCa2 cells subjected to metabolic stress in Nupr1-silenced conditions. DNA repair and cell cycle-associated gene expression was confirmed by real-time quantitative PCR (qRT-PCR). Nupr1 and AURKA protective role were analyzed using RNA interference (RNAi) silencing or overexpression. DNA damage and autophagy were analyzed by Western blot analysis and immunofluorescence. RESULTS: We showed that both Nupr1 and HIF1α are coexpressed in human pancreatic ductal adenocarcinoma (PDAC) samples and negatively correlate with survival time. PDAC-derived cells submitted to hypoxia and/or glucose starvation induce DNA damage-dependent cell death concomitantly to the overexpression of stress protein Nupr1. Affymetrix-based transcriptoma analysis reveals that Nupr1 knockdown enhances DNA damage and alters the expression of several genes involved in DNA repair and cell-cycle progression. Expression of some of these genes is common to hypoxia and glucose starvation, such as Aurka gene, suggesting that Nupr1 overexpression counteracts the transcriptional changes occurring under metabolic stress. The molecular mechanism by which hypoxia and glucose starvation induce cell death involves autophagy-associated, but not caspase-dependent, cell death. Finally, we have found that AURKA expression is partially regulated by Nupr1 and plays a major role in this response. CONCLUSIONS: Our data reveal that Nupr1 is involved in a defense mechanism that promotes pancreatic cancer cell survival when exposed to metabolic stress.

Homotypic cell cannibalism, a cell-death process regulated by the nuclear protein 1, opposes to metastasis in pancreatic cancer.

Pancreatic adenocarcinoma (PDAC) is an extremely deadly disease for which all treatments available have failed to improve life expectancy significantly. This may be explained by the high metastatic potential of PDAC cells, which results from their dedifferentiation towards a mesenchymal phenotype. Some PDAC present cell-in-cell structures whose origin and significance are currently unknown. We show here that cell-in-cells form after homotypic cell cannibalism (HoCC). We found PDAC patients whose tumours display HoCC develop less metastasis than those without. In vitro, HoCC was promoted by inactivation of the nuclear protein 1 (Nupr1), and was enhanced by treatment with transforming growth factor ß. HoCC ends with death of PDAC cells, consistent with a metastasis suppressor role for this phenomenon. Hence, our data indicates a protective role for HoCC in PDAC and identifies Nupr1 as a molecular regulator of this process.

The human NUPR1/P8 gene is transcriptionally activated by transforming growth factor ß via the SMAD signalling pathway.

NUPR1 (nuclear protein 1), also called P8 (molecular mass 8 kDa) or COM1 (candidate of metastasis 1), is involved in the stress response and in cancer progression. In the present study, we investigated whether human NUPR1 expression was regulated by TGFß (transforming growth factor ß), a secreted polypeptide largely involved in tumorigenesis. We demonstrate that the expression of NUPR1 was activated by TGFß at the transcriptional level. We show that this activation is mediated by the SMAD proteins, which are transcription factors specifically involved in the signalling of TGFß superfamily members. NUPR1 promoter analysis reveals the presence of a functional TGFß-response element binding the SMAD proteins located in the genomic DNA region corresponding to the 5'-UTR (5'-untranslated region). Altogether, the molecular results of the present study, which demonstrate the existence of a TGFß/SMAD/NUPR1 activation cascade, open the way to consider and investigate further a new mechanism enabling TGFß to promote tumorigenesis by inducing stress resistance.

Nuclear protein 1 promotes pancreatic cancer development and protects cells from stress by inhibiting apoptosis.

Pancreatic ductal adenocarcinoma (PDAC) has the lowest survival rate of all cancers and shows remarkable resistance to cell stress. Nuclear protein 1 (Nupr1), which mediates stress response in the pancreas, is frequently upregulated in pancreatic cancer. Here, we report that Nupr1 plays an essential role in pancreatic tumorigenesis. In a mouse model of pancreatic cancer with constitutively expressed oncogenic Kras(G12D), we found that loss of Nupr1 protected from the development of pancreatic intraepithelial neoplasias (PanINs). Further, in cultured pancreatic cells, nutrient deprivation activated Nupr1 expression, which we found to be required for cell survival. We found that Nupr1 protected cells from stress-induced death by inhibiting apoptosis through a pathway dependent on transcription factor RelB and immediate early response 3 (IER3). NUPR1, RELB, and IER3 proteins were coexpressed in mouse PanINs from Kras(G12D)-expressing pancreas. Moreover, pancreas-specific deletion of Relb in a Kras(G12D) background resulted in delayed in PanIN development associated with a lack of IER3 expression. Thus, efficient PanIN formation was dependent on the expression of Nupr1 and Relb, with likely involvement of IER3. Finally, in patients with PDAC, expression of NUPR1, RELB, and IER3 was significantly correlated with a poor prognosis. Cumulatively, these results reveal a NUPR1/RELB/IER3 stress-related pathway that is required for oncogenic Kras(G12D)-dependent transformation of the pancreas.

p8 expression controls pancreatic cancer cell migration, invasion, adhesion, and tumorigenesis.

p8 is a stress gene whose activity is necessary for tumor development and progression. The acquisition of invasive properties by transformed cells is a key event in tumor development. In order to establish whether p8 is involved or not in this phenomenon, we assessed the capacity of p8 at influencing cell adhesion, migration, invasion, and tumorigenesis of pancreatic cancer cells. p8 expression was knocked down by a small interfering RNA (siRNA) in pancreatic cancer-derived Panc-1 and MiaPaCa-2 cells and subsequent changes in cell adhesion, migration, invasion, and tumorigenesis were assessed. Influence of p8 silencing on gene expression was analyzed using cDNA microarrays. The influence of inhibiting CDC42, one of the genes most over-expressed in p8-silenced cells, on the changes observed in p8-silenced cells was also evaluated. Finally, the tumorigenic capacities of Panc-1 cells transfected with control siRNA or p8 siRNA were compared by assessing their ability to form colonies in soft agar and to grow as xenografts in nude mice. Knocking-down p8 in pancreatic cancer cells in vitro decreased migration and invasion while increasing cell adhesion; over-expression produced the opposite effect. Knocking down CDC42 reversed almost completely the effects of silencing p8 in vitro. Finally, cells transfected with p8 siRNA were almost unable to form colonies in soft agar. In addition, p8-deficient Panc-1 cells did not develop tumors when injected subcutaneously in nude mice. In conclusion, p8 expression controls pancreatic cancer cell migration, invasion and adhesion, three processes required for metastasis, at least in part, through CDC42, a major regulator of cytoskeleton organization.

Absence of tumor suppressor tumor protein 53-induced nuclear protein 1 (TP53INP1) sensitizes mouse thymocytes and embryonic fibroblasts to redox-driven apoptosis.

The p53-transcriptional target TP53INP1 is a potent stress-response protein promoting p53 activity. We previously showed that ectopic overexpression of TP53INP1 facilitates cell cycle arrest as well as cell death. Here we report a study investigating cell death in mice deficient for TP53INP1. Surprisingly, we found enhanced stress-induced apoptosis in TP53INP1-deficient cells. This observation is underpinned in different cell types in vivo (thymocytes) and in vitro (thymocytes and MEFs), following different types of injury inducing either p53-dependent or -independent cell death. Nevertheless, absence of TP53INP1 is unable to overcome impaired cell death of p53-deficient thymocytes. Stress-induced ROS production is enhanced in the absence of TP53INP1, and antioxidant NAC complementation abolishes increased sensitivity to apoptosis of TP53INP1-deficient cells. Furthermore, antioxidant defenses are defective in TP53INP1-deficient mice in correlation with ROS dysregulation. Finally, we show that autophagy is reduced in TP53INP1-deficient cells both at the basal level and upon stress. Altogether, these data show that impaired ROS regulation in TP53INP1-deficient cells is responsible for their sensitivity to induced apoptosis. In addition, they suggest that this sensitivity could rely on a defect of autophagy. Therefore, these data emphasize the role of TP53INP1 in protection against cell injury.

Nupr1: the Swiss-knife of cancer.

Nupr1 is a small, highly basic and loosely folded multifunctional protein whose expression is induced by several stresses. Its relation to cancer was first suggested by its overexpression in several human malignancies and the association of its expression with breast cancer metastasis. Accordingly, Nupr1 is structurally related to the high-mobility group (HMG) of transcriptional regulators, which play a key role in the stress response and in cancer progression. Nupr1 interacts with numerous partners to regulate cell cycle, programmed cell death, autophagy, chromatin accessibility, and transcription, and its expression is required for regulation of TGFß activity. Pleiotropic functions accomplished by Nupr1 depend on its molecular partners, its location into the cell, its expression level and on the cell-type. Nupr1 might be a new drug-targetable protein whose blockade would prevent cancer progression and metastasis development.