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Background: Among people living with HIV-1 (PHIV), immunological non-responders (INR) experience incomplete immune recovery despite suppressive antiretroviral treatment (ART), facing more severe non-AIDS events than immunological responders (IR) due to higher chronic immune activation and inflammation (cIA/I). We analyzed the HIV-1 reservoir and immunometabolism in monocytes as a source of cIA/I., Methods: Cross-sectional study in which 110 participants were enrolled: 25 treatment-naïve; 35 INR; 40 IR; and 10 healthy controls. Cell-associated HIV-1-DNA (HIV-DNA) and -RNA (HIV-RNA) were measured in FACS-isolated monocytes using digital droplet PCR. Intact, 5' deleted, and 3' deleted proviruses were quantified by the intact proviral DNA assay. Systemic inflammation, monocyte immunophenotype, and immunometabolism were characterized by immunoassays, flow cytometry, and real-time cellular bioenergetics measurements, respectively., Findings: Monocytes from INR harbor higher HIV-RNA and HIV-DNA levels than IR. HIV-RNA was found in 14/21 treatment-naïve [2512 copies/10 6 TBP (331-4666)], 17/33 INR [240 (148-589)], and 15/28 IR [144 (15-309)], correlating directly with sCD163, IP-10, GLUT1 high cells and glucose uptake, and inversely with the CD4 + /CD8 + ratio. HIV-DNA was identified in all participants with detectable HIV-RNA, with intact provirus in 9/12 treatment-naïve [13 copies/10 6 monocytes (7-44)], 8/14 INR [46 (18-67)], and 9/13 IR [9 (7-24)]. INR presented glucose metabolism alterations and mitochondrial impairment; decreased coupling efficiency and BHI, and increased mitochondrial dysfunction inversely correlating with the CD4 + /CD8 + ratio., Interpretation: HIV-RNA, more than HIV-DNA, in monocytes and their altered metabolism are factors associated with the higher cIA/I that characterize INR., Funding: This work was supported by the European Regional Development Fund, ISCIII, grant PI20/01646. Other funding sources: Instituto de Salud Carlos III through the Subprogram Miguel Servet (CP19/00159) to AGV, PFIS contracts (FI19/00304) to EMM, (FI21/00165) to ASA, and (FI19/00083) to CGC, and a mobility grant (MV21/00103) to EMM, from the Ministerio de Ciencia e Innovación, Spain. AJM was granted by a CSL Centenary Award., Competing Interests: Declaration of interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier B.V. All rights reserved.)

Despite effective antiretroviral therapy (ART), 15-30% of people with HIV experience poor CD4 + T-cell recovery, termed immunologic non-responders (INR). This study aims to evaluate whether pre-ART plasma levels of interleukin-6 (IL-6), interferon gamma-induced protein-10 (IP-10), macrophage inflammatory protein-1-β (MIP-1β), and/or pentraxin-3 (PTX-3) could predict subsequent immunologic recovery. Seventy-four participants were enrolled and classified as INR and immunologic responders (IR) based on CD4 + /CD8 + ratio increase over 24 months after starting ART. The results showed no significant differences in cytokine levels between INR and IR. Therefore, IL-6, IP-10, MIP-1β, and PTX-3 were unsuitable as predictive markers of poor immune recovery., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Mejías-Trueba, Saborido-Alconchel, Serna-Gallego, Trujillo-Rodríguez, Muñoz-Muela, Llaves-Flores, Espinosa, Roca-Oporto, Herrero, Sotomayor and López-Cortes.)

Objective: To compare the long-term effects on immune parameters, inflammation, and HIV-1 reservoir after switching to a two-drug (2DR) versus maintaining an integrase inhibitor (InSTI)-based three-drug regimen (3DR)., Methods: Cross-sectional study in which HIV-1 treatment-naïve people started and maintained an InSTI-based 3DR or, at different times, switched to 2DR (dolutegravir or darunavir/cobicistat + lamivudine). CD4 + and CD8 + T-cell activation and exhaustion, plasma concentrations of hs-CRP, D-dimer, P-selectin, IL-1β, IL-6, TNF-α, IFN-γ, IP-10, sTNFR-I/II, MIP-1α/β, I-FABP, LBP, sCD14, sCD163, MCP-1, and cellular-associated HIV-1-DNA and -RNA were quantified by flow cytometry, different immunoassays, and droplet digital PCR, respectively. The U de Mann-Whitney test evaluated differences between 3DR and 2DR. Immune recovery was evaluated using a general linear model for repeated measures adjusted for different co-variables., Results: Fifty participants per group were included. The median time on 3DR was 82 months for the 3DR group and 30 months for the 2DR group, after which it switched to 2DR for a median of 57 months. We did not find differences between both groups in any of the parameters analyzed. Specifically, some values in 3DR and 2DR were hs-CRP, 0.92 mg/L (0.45-2.23) vs. 1.23 (0.61-2.38); D-dimer, 190.0 µg/L (150.0-370.0) vs. 190.0 (150.0-397.5); IL-6, 2.8 pg/mL (1.3-5.3) vs. 3.2 (2.1-4.7); sCD14, 4.5 ng/mL (3.3-6.2) vs. 5.0 (3.6-6.1), respectively, all p ≥ 0.399., Conclusion: In the long term, switching to 2DR does not negatively affect immunologic parameters, inflammatory markers, or HIV-1 reservoir., Clinical Trial Registration: identifier NCT04076423., Competing Interests: LL-C has received unrestricted research funding outside the submitted work from ViiV Healthcare, Merck Sharp & Dohme, and Gilead Sciences, as well as lecture fees from Gilead Sciences. NE has received unrestricted research funding outside the submitted work from Merck Sharp & Dohme, and fees as a consultant and speaker from ViiV Healthcare, Merck Sharp & Dohme, and Gilead Sciences, as well as travel grants from Gilead Sciences and Merck Sharp for attending conferences. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Saborido-Alconchel, Serna-Gallego, Trujillo-Rodriguez, Muñoz-Muela, Álvarez-Ríos, Lozano, Llaves-Flores, Espinosa, Roca-Oporto, Herrero, Sotomayor, Gutierrez-Valencia and Lopez-Cortes.)

Background: Dual therapy (DT) has shown comparable results to triple therapy (TT) in efficacy and other immunological aspects. However, there are still some concerns about DT, including several immunological features. Therefore, we evaluated whether HIV-1-specific memory T-cell responses and exhaustion phenotypes are adversely influenced after simplification to DT., Methods: HIV-1-specific CD4 + and CD8 + T-cell responses were assessed by intracellular cytokine and degranulation marker staining, and polyfunctionality indexes after stimulation with a Gag peptide pool. Exhaustion phenotypes were evaluated by PD-1, TIM-3, and LAG-3 expression in CD4 + and CD8 + T cells., Results: Forty participants in the TRIDUAL trial (ClinicalTrials.gov: NCT03447873) who were randomized to continue integrase inhibitor-based TT (n = 20) or to switch to DT (dolutegravir or darunavir/cobicistat plus lamivudine) (n = 20). After 96 weeks, the magnitude of CD4 + and CD8 + T-cell responses was similar in both treatment arms (p = 0.221 and p = 0.602, respectively). The CD4 + polyfunctionality index decreased in the TT arm (p = 0.013) and remained stable in the DT arm, while the polyfunctionality of CD8 + T cells was unchanged in both arms. There was a significant decrease in the expression of PD-1, TIM-3, and the co-expression of PD-1 + TIM-3 + LAG-3 + , and PD-1 +TIM-3 + in both CD4 + and CD8 + T cells. However, the decrease in the expression of exhaustion markers did not improve HIV-1-specific T-cell responses., Conclusions: Our results suggest that simplification to DT does not negatively influence the HIV-1-specific T-cell response or the exhaustion phenotype after 96 weeks of follow-up., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Background: This was a substudy of a Phase IV, randomized clinical trial (ClinicalTrials.gov identifier: NCT04295460) aiming to compare the activity of dolutegravir/lamivudine versus dolutegravir plus tenofovir alafenamide/emtricitabine (DTG + TAF/FTC) in the male genital tract., Methods: Participants were asymptomatic adults without sexually transmitted diseases, treatment-naive people living with HIV (PLWH), with CD4+ T cell counts >200 cells/mm3 and plasma HIV-1-RNA levels >5000 and <500 000 copies/mL, randomized (1:1) to DTG + TAF/FTC or dolutegravir/lamivudine. Blood plasma (BP) and seminal plasma (SP) were collected at baseline and Weeks 4, 8, 12 and 24. HIV-1-RNA was measured in BP and SP using the Cobas 6800 system (Roche Diagnostics) with a lower detection limit of 20 copies/mL. The primary efficacy endpoint was the proportion of subjects with undetectable SP HIV-1-RNA at Week 12 by intention-to-treat analysis., Results: Fifteen participants in the DTG + TAF/FTC and 16 in the dolutegravir/lamivudine arms were analysed, with basal SP viral load of 4.81 (4.30-5.43) and 4.76 (4.09-5.23), P = 0.469, respectively. At Week 12, only one participant in each treatment arm had a detectable SP HIV-1-RNA (DTG + TAF/FTC, 141 copies/mL; dolutegravir/lamivudine, 61 copies/mL). Based on the estimated means, there was no significant difference in the decay of HIV-1-RNA in both BP and SP over time between the two arms of treatment (F = 0.452, P = 0.662, and F = 1.147, P = 0.185, respectively)., Conclusions: After 12 weeks of treatment, there were no differences in the percentage of undetectable SP HIV-1-RNA in naive PLWH who started dolutegravir/lamivudine compared with DTG + TAF/FTC., (© The Author(s) 2023. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy.)

Background: Data on SARS-CoV-2 mRNA vaccine immunogenicity in people living with human immunodeficiency virus (PLWH) and discordant immune response (DIR) are currently limited. Therefore, we compare the immunogenicity of these vaccines in DIR and immunological responders (IR)., Methods: A prospective cohort that enrolled 89 participants. Finally, 22 IR and 24 DIR were analyzed before vaccination (T 0 ), one (T 1 ) and six months (T 2 ) after receiving BNT162b2 or mRNA-1273 vaccine. Additionally, 10 IR and 16 DIR were evaluated after a third dose (T 3 ). Anti-S-RBD IgG, neutralizing antibodies (nAb), neutralization activity, and specific memory B cells were quantified. Furthermore, specific CD4 + and CD8 + responses were determined by intracellular cytokine staining and polyfunctionality indexes (Pindex)., Results: At T 1 , all participants developed anti-S-RBD. 100% IR developed nAb compared to 83.3% DIR. Spike-specific B cells were detected in all IR and 21/24 DIR. Memory CD4 + T cells responded in 5/9 IR and 7/9 DIR, mainly based on the expression of IFN-γ and TNF-α, with a higher Pindex in DIR. Memory CD8 + T cells responded in only four participants in each group. At T 2 , anti-S-RBD and nAb titers were higher in DIR than in IR. In both groups, there was an increase in specific B memory cells, higher in DIR. Six IR and five DIR maintained a specific memory CD4 + response. Memory CD8 + response was preserved in IR but was lost in DIR. In a multivariate linear regression analysis, receiving mRNA-1273 instead of BNT162b2 played a prominent role in the results., Conclusions: Our data suggest that PLWH with DIR can mount an immune response similar to those with higher CD4 + , provided they receive the mRNA-1273 vaccine instead of others less immunogenic., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 López-Cortés, Saborido-Alconchel, Trujillo-Rodríguez, Serna-Gallego, Llaves-Flores, Muñoz-Muela, Pérez-Santos, Lozano, Mejias-Trueba, Roca, Espinosa and Gutiérrez-Valencia.)

Objectives: To evaluate whether simplification of antiretroviral treatment to dual therapy (DT) negatively impacts immune recovery (IR), immune activation and inflammation (IA/I), and HIV reservoir., Methods: An open-label, single-centre, randomized controlled trial conducted in adult virologically suppressed HIV-infected patients on triple therapy (TT) with elvitegravir-cobicistat, emtricitabine and tenofovir alafenamide or dolutegravir (DTG), abacavir, and lamivudine (3TC). Participants were randomized to continue TT or switch to DTG, or darunavir/cobicistat (DRVc) plus 3TC. IR was assessed by CD4 + /CD8 + ratio at 48 and 96 weeks. Changes in immune activation, proliferation, exhaustion, senescence, and apoptosis in CD4 + and CD8 + T cells, plasma sCD14, hsCRP, D-dimers, β2-microglobulin, IL-6, TNF-α and IP-10 levels, cell-associated HIV-DNA (CA-DNA), and unspliced HIV-RNA (usRNA) were also analysed., Results: One hundred and fifty-one participants were enrolled. Fourteen patients did not complete the follow up. In the ITT and PP analysis, the IR was similar between the treatment arms. In the ITT analysis, the median increase in CD4 + /CD8 + ratio was 0.10, 0.04, and 0.07 at week 48, and 0.09, 0.05, and 0.08 at week 96 for TT, DTG/3TC, and DRVc/3TC, respectively. After adjusting for confounding factors, the slopes of changes in CD4 + /CD8 + ratio over time were independent of treatment (F = 1.699; p = 0.436) and related only to baseline values (F = 756.871; p = 0.000). There were no differences in IA/I, CA-DNA, or usRNA between treatment arms., Discussion: Both IR and IA/I, CA-DNA, and usRNA were similar in the three treatment groups, regardless of maintaining TT or simplifying to DTG/3TC or DRVc/3TC in virologically suppressed HIV-infected patients., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objective: We aimed to evaluate the anti-CD4 IgG role in the poor immune recovery of immunological nonresponder people with HIV (INR)., Design: INR display low CD4 + T-cell increase despite long-term undetectable viremia. Among other factors, autologous anti-CD4 IgG-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells has been proposed to cause CD4 + T-cell depletion., Methods: Plasma anti-CD4 IgG levels were quantified and purified by chromatography columns for the subsequent use in a coculture of CD4 + T and NK cells. We analyzed NK cell degranulation markers (CD107a, perforin and granzyme B) and IFN-γ release, and CD4 + T-cell death. Binding affinity of anti-CD4 IgG for CD4 + T cells was also assessed., Results: A total of 168 individuals were enrolled (INR, 56; immunological responders, 40; treatment-naive, 39; and healthy controls, 33). The highest anti-CD4 IgG levels were found in treatment-naive people with HIV (PWH), followed by participants on treatment. There were no correlations between anti-CD4 IgG levels and CD4 + T-cell counts. In a 15-participant subgroup (naive, immunological responders, and INR), anti-CD4 IgG induced a slight NK-cell expression of degranulation markers and IFN-γ; however, the percentage of CD4 + T-cell death was negligible. Consistently, no significant changes in NK cell polyfunctionality were observed. In addition, purified anti-CD4 IgG showed scarce binding affinity for CD4 + T cells. These results were similar in all analyzed participant groups., Conclusion: Our results suggest that autologous anti-CD4 IgG neither trigger CD4 + T-cell death by ADCC nor are responsible for CD4 + lymphocyte depletion in INR., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The SARS-CoV-2 pandemic has overwhelmed hospital services due to the rapid transmission of the virus and its severity in a high percentage of cases. Having tools to predict which patients can be safely early discharged would help to improve this situation., Methods: Patients confirmed as SARS-CoV-2 infection from four Spanish hospitals. Clinical, demographic, laboratory data and plasma samples were collected at admission. The patients were classified into mild and severe/critical groups according to 4-point ordinal categories based on oxygen therapy requirements. Logistic regression models were performed in mild patients with only clinical and routine laboratory parameters and adding plasma pro-inflammatory cytokine levels to predict both early discharge and worsening., Results: 333 patients were included. At admission, 307 patients were classified as mild patients. Age, oxygen saturation, Lactate Dehydrogenase, D-dimers, neutrophil-lymphocyte ratio (NLR), and oral corticosteroids treatment were predictors of early discharge (area under curve (AUC), 0.786; sensitivity (SE) 68.5%; specificity (S), 74.5%; positive predictive value (PPV), 74.4%; and negative predictive value (NPV), 68.9%). When cytokines were included, lower interferon-γ-inducible protein 10 and higher Interleukin 1 beta levels were associated with early discharge (AUC, 0.819; SE, 91.7%; S, 56.6%; PPV, 69.3%; and NPV, 86.5%). The model to predict worsening included male sex, oxygen saturation, no corticosteroids treatment, C-reactive protein and Nod-like receptor as independent factors (AUC, 0.903; SE, 97.1%; S, 68.8%; PPV, 30.4%; and NPV, 99.4%). The model was slightly improved by including the determinations of interleukine-8, Macrophage inflammatory protein-1 beta and soluble IL-2Rα (CD25) (AUC, 0.952; SE, 97.1%; S, 98.1%; PPV, 82.7%; and NPV, 99.6%)., Conclusions: Clinical and routine laboratory data at admission strongly predict non-worsening during the first two weeks; therefore, these variables could help identify those patients who do not need a long hospitalization and improve hospital overcrowding. Determination of pro-inflammatory cytokines moderately improves these predictive capacities., Competing Interests: The authors have declared that no competing interests exist.

SARS-CoV-2 specific T-cell response has been associated with disease severity, immune memory and heterologous response to endemic coronaviruses. However, an integrative approach combining a comprehensive analysis of the quality of SARS-CoV-2 specific T-cell response with antibody levels in these three scenarios is needed. In the present study, we found that, in acute infection, while mild disease was associated with high T-cell polyfunctionality biased to IL-2 production and inversely correlated with anti-S IgG levels, combinations only including IFN-γ with the absence of perforin production predominated in severe disease. Seven months after infection, both non-hospitalised and previously hospitalised patients presented robust anti-S IgG levels and SARS-CoV-2 specific T-cell response. In addition, only previously hospitalised patients showed a T-cell exhaustion profile. Finally, combinations including IL-2 in response to S protein of endemic coronaviruses were the ones associated with SARS-CoV-2 S-specific T-cell response in pre-COVID-19 healthy donors' samples. These results could have implications for protective immunity against SARS-CoV-2 and recurrent COVID-19 and may help for the design of new prototypes and boosting vaccine strategies., (© 2022 The Authors. Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.)

Viral and host immune kinetics during acute COVID-19 and after remission of acute symptoms need better characterization. SARS-CoV-2 RNA, anti-SARS-CoV-2 IgA, IgM, and IgG antibodies, and proinflammatory cytokines were measured in sequential samples from hospitalized COVID-19 patients during acute infection and six months following diagnosis. Twenty four laboratory confirmed COVID-19 patients with mild/moderate and severe COVID-19 were included. Most were males (83%) with a median age of 61 years. Twenty one percent were admitted to the intensive care unit (ICU) and eight of them (33.3%) met the criteria for severe COVID-19 disease. A delay in SARS-CoV-2 levels' decline during the first six days of follow up, and viral load persistence until month 3 were related to severe COVID-19, but not viral load levels at the diagnosis. Higher levels of anti-SARS-CoV-2 IgA, IgM, IgG and the cytokines IL-6, IL-8 and MIP-1β at the diagnosis time were related to the severe COVID-19 outcome. Higher levels of MIP-1β, IL-1β, MIP-1α and IFN-γ were observed at month 1 and 3 during mild/moderate disease, compared to severe COVID-19. IgG persisted at low levels after six months of diagnosis. In conclusion, higher concentrations of IgA, IgM, and IgG, and IL-6, IL-8 and MIP-1β are identified as early predictors of COVID-19 severity, whereas no significant association is found between baseline SARS-COV-2 viral load and COVID-19 severity.

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 infection induces an exacerbated inflammation driven by innate immunity components. Dendritic cells (DCs) play a key role in the defense against viral infections, for instance plasmacytoid DCs (pDCs), have the capacity to produce vast amounts of interferon-alpha (IFN-α). In COVID-19 there is a deficit in DC numbers and IFN-α production, which has been associated with disease severity. In this work, we described that in addition to the DC deficiency, several DC activation and homing markers were altered in acute COVID-19 patients, which were associated with multiple inflammatory markers. Remarkably, previously hospitalized and nonhospitalized patients remained with decreased numbers of CD1c+ myeloid DCs and pDCs seven months after SARS-CoV-2 infection. Moreover, the expression of DC markers such as CD86 and CD4 were only restored in previously nonhospitalized patients, while no restoration of integrin β7 and indoleamine 2,3-dyoxigenase (IDO) levels were observed. These findings contribute to a better understanding of the immunological sequelae of COVID-19., (© 2021. The Author(s), under exclusive licence to CSI and USTC.)

Purpose: This study was aimed to determine the impact of hydroxytyrosol (HT), a minor compound found in olive oil, on breast cancer stem cells (BCSCs) and the migration capacity of triple-negative breast cancer (TNBC) cell lines through the alteration of epithelial-to-mesenchymal transition (EMT) and embryonic signaling pathways., Methods: BCSCs self-renewal was determined by the mammosphere-forming efficiency in SUM159PT, BT549, MDA-MB-231 and Hs578T TNBC cell lines. Flow cytometric analysis of CD44 + /CD24 -/low and aldehyde dehydrogenase positive (ALDH + ) subpopulations, migration by the "wound healing assay", invasion and Western blot of EMT markers and TGFβ signaling were investigated in SUM159PT, BT549 and MDA-MB-231 cell lines. Wnt/β-catenin signaling was assessed by Western blot in BT549 cells expressing WNT1 and MDA-MB-231 cells. Changes in TGFβ activity was determined by SMAD Binding Element (SBE) reporter assay., Results: HT reduced BCSCs self-renewal, ALDH + (aldehyde dehydrogenase) and CD44 + /CD24 -/low subpopulations, tumor cell migration and invasion. Consistently, HT suppressed Wnt/β-catenin signaling by decreasing p-LRP6, LRP6, β-catenin and cyclin D1 protein expression and the EMT markers SLUG, ZEB1, SNAIL and VIMENTIN. Finally, HT inhibited p-SMAD2/3 and SMAD2/3 in SUM159PT, BT549 and MDA-MB-231 cells, what was correlated with a less TGFβ activity., Conclusion: In conclusion, we report for the first time the inhibitory role of HT on BCSCs and tumor cell migration by targeting EMT, Wnt/β-catenin and TGFβ signaling pathways. Our findings highlight the importance of the chemopreventive compound HT as a novel candidate to be investigated as an alternative targeted therapy for TNBC.

Purpose: On the basis of the identified stress-independent cellular functions of activating transcription factor 4 (ATF4), we reported enhanced ATF4 levels in MCF10A cells treated with TGFβ1. ATF4 is overexpressed in patients with triple-negative breast cancer (TNBC), but its impact on patient survival and the underlying mechanisms remain unknown. We aimed to determine ATF4 effects on patients with breast cancer survival and TNBC aggressiveness, and the relationships between TGFβ and ATF4. Defining the signaling pathways may help us identify a cell signaling-tailored gene signature. Experimental Design: Patient survival data were determined by Kaplan-Meier analysis. Relationship between TGFβ and ATF4, their effects on aggressiveness (tumor proliferation, metastasis, and stemness), and the underlying pathways were analyzed in three TNBC cell lines and in vivo using patient-derived xenografts (PDX). Results: ATF4 overexpression correlated with TNBC patient survival decrease and a SMAD-dependent crosstalk between ATF4 and TGFβ was identified. ATF4 expression inhibition reduced migration, invasiveness, mammosphere-forming efficiency, proliferation, epithelial-mesenchymal transition, and antiapoptotic and stemness marker levels. In PDX models, ATF4 silencing decreased metastases, tumor growth, and relapse after chemotherapy. ATF4 was shown to be active downstream of SMAD2/3/4 and mTORC2, regulating TGFβ/SMAD and mTOR/RAC1-RHOA pathways independently of stress. We defined an eight-gene signature with prognostic potential, altered in 45% of 2,509 patients with breast cancer. Conclusions: ATF4 may represent a valuable prognostic biomarker and therapeutic target in patients with TNBC, and we identified a cell signaling pathway-based gene signature that may contribute to the development of combinatorial targeted therapies for breast cancer. Clin Cancer Res; 24(22); 5697-709. ©2018 AACR ., (©2018 American Association for Cancer Research.)