We present a hyper-heuristic approach to solve Orienteering Problem with Hotel Selection (OPHS). In practical applications, OPHS appears when a tourist is planning to visit various attractions and ...there is not enough time to reach all of them in a single day. Therefore, the tourist must build a tour within several days by selecting hotels, where each day has a different time budget. We propose a hyper-heuristic based on a Large Neighborhood Search, composed by a set of low-level heuristics that satisfy the different constraints associated with the problem. We put special emphasis on collaboration between low-level heuristics in order to guide the algorithm to more promising areas. We use 395 benchmark instances with known optimal solutions. This approach proves to be a more general method, with a simpler design compared to the literature, and is able to find 217 of the 395 known optimal solutions, in acceptable computational times.
Prostate cancer (PCa) displays diverse intra-tumoral traits, impacting its progression and treatment outcomes. This study aimed to refine PCa cell culture conditions for dynamic monitoring of ...androgen receptor (AR) activity at the single-cell level. We introduced an extracellular matrix-Matrigel (ECM-M) culture model, enhancing cellular tracking during bioluminescence single-cell imaging while improving cell viability. ECM-M notably tripled the traceability of poorly adherent PCa cells, facilitating robust single-cell tracking, without impeding substrate permeability or AR response. This model effectively monitored AR modulation by antiandrogens across various PCa cell lines. Single-cell imaging unveiled heterogeneous antiandrogen responses within populations, correlating non-responsive cell proportions with drug IC50 values. Integrating ECM-M culture with the PSEBC-TSTA biosensor enabled precise characterization of ARi responsiveness within diverse cell populations. Our ECM-M model stands as a promising tool to assess heterogeneous single-cell treatment responses in cancer, offering insights to link drug responses to intracellular signaling dynamics. This approach enhances our comprehension of the nuanced and dynamic nature of PCa treatment responses.
The androgen receptor (AR) is an established orchestrator of cell metabolism in prostate cancer (PCa), notably by inducing an oxidative mitochondrial program. Intriguingly, AR regulates cytoplasmic ...isocitrate dehydrogenase 1 (IDH1), but not its mitochondrial counterparts IDH2 and IDH3. Here, we aimed to understand the functional role of IDH1 in PCa. Mouse models, in vitro human PCa cell lines, and human patient-derived organoids (PDOs) were used to study the expression and activity of IDH enzymes in the normal prostate and PCa. Genetic and pharmacological inhibition of IDH1 was then combined with extracellular flux analyses and gas chromatography-mass spectrometry for metabolomic analyses and cancer cell proliferation in vitro and in vivo. In PCa cells, more than 90% of the total IDH activity is mediated through IDH1 rather than its mitochondrial counterparts. This profile seems to originate from the specialized prostate metabolic program, as observed using mouse prostate and PDOs. Pharmacological and genetic inhibition of IDH1 impaired mitochondrial respiration, suggesting that this cytoplasmic enzyme contributes to the mitochondrial tricarboxylic acid cycle (TCA) in PCa. Mass spectrometry-based metabolomics confirmed this hypothesis, showing that inhibition of IDH1 impairs carbon flux into the TCA cycle. Consequently, inhibition of IDH1 decreased PCa cell proliferation in vitro and in vivo. These results demonstrate that PCa cells have a hybrid cytoplasmic-mitochondrial TCA cycle that depends on IDH1. This metabolic enzyme represents a metabolic vulnerability of PCa cells and a potential new therapeutic target.
Cancer cell heterogeneity is well-documented. Therefore, techniques to monitor single cell heterogeneous responses to treatment are needed. We developed a highly translational and quantitative ...bioluminescence microscopy method to measure single cell androgen receptor (AR) activity modulation by antiandrogens from fluid biopsies. We showed that this assay can detect heterogeneous cellular response to drug treatment and that the sum of single cell AR activity can mirror the response in the whole cell population. This method may thus be used to monitor heterogeneous dynamic treatment responses in cancer cells.
The prostate is metabolically unique: it produces high levels of citrate for secretion via a truncated tricarboxylic acid (TCA) cycle to maintain male fertility. In prostate cancer (PCa), this ...phenotype is reprogrammed, making it an interesting therapeutic target. However, how the truncated prostate TCA cycle works is still not completely understood.
We optimized targeted metabolomics in mouse and human organoid models in ex vivo primary culture. We then used stable isotope tracer analyses to identify the pathways that fuel citrate synthesis.
First, mouse and human organoids were shown to recapitulate the unique citrate-secretory program of the prostate, thus representing a novel model that reproduces this unusual metabolic profile. Using stable isotope tracer analysis, several key nutrients were shown to allow the completion of the prostate TCA cycle, revealing a much more complex metabolic profile than originally anticipated. Indeed, along with the known pathway of aspartate replenishing oxaloacetate, glutamine was shown to fuel citrate synthesis through both glutaminolysis and reductive carboxylation in a GLS1-dependent manner. In human organoids, aspartate entered the TCA cycle at the malate entry point, upstream of oxaloacetate. Our results demonstrate that the citrate-secretory phenotype of prostate organoids is supported by the known aspartate–oxaloacetate–citrate pathway, but also by at least three additional pathways: glutaminolysis, reductive carboxylation, and aspartate–malate conversion.
Our results add a significant new dimension to the prostate citrate-secretory phenotype, with at least four distinct pathways being involved in citrate synthesis. Better understanding this distinctive citrate metabolic program will have applications in both male fertility as well as in the development of novel targeted anti-metabolic therapies for PCa.
•Targeted metabolomics and stable isotope tracer analysis were optimized in mouse and human prostate organoids.•Organoids recapitulate the unique citrate-secretory phenotype of the prostate.•Glutamine fuels citrate synthesis for secretion by glutaminolysis and reductive carboxylation.•Aspartate enters the TCA cycle at different entry points in mouse and human prostate organoids for citrate production.•We revealed a much more complex TCA cycle in the prostate than originally anticipated.
In the fight against androgen-sensitive prostate cancer, the enzyme 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) is an attractive therapeutic target considering its key role in the formation of ...androgenic steroids. In this study, we attempted to assess the in vivo efficacy of the compound RM-532-105, an androsterone derivative developed as an inhibitor of 17β-HSD3, in the prostate cancer model of androgen-sensitive LAPC-4 cells xenografted in nude mice. RM-532-105 did not inhibit the tumor growth induced by 4-androstene-3,17-dione (4-dione); rather, the levels of the androgens testosterone (T) and dihydrotestosterone (DHT) increased within the tumors. In plasma, however, DHT levels increased but T levels did not. In troubleshooting experiments, the non-androgenic potential of RM-532-105 was confirmed by two different assays (LAPC-4 proliferation and androgen receptor transcriptional activity assays). The enzyme 5α-reductase was also revealed to be the predominant enzyme metabolizing 4-dione in LAPC-4 cells, yielding 5α-androstane-3,17-dione and not T. Other 17β-HSDs than 17β-HSD3 seem responsible in the androgen synthesis. From experiments with LAPC-4 cells, we fortuitously came across the interesting finding that 17β-HSD3 inhibitor RM-532-105 is concentrated inside tumors.
Localized prostate cancer (PCa) is often curable, whereas metastatic disease treated by castration inevitably progresses toward castration-resistant PCa (CRPC). Most CRPC treatments target androgen ...receptor (AR) signaling. However, not all CRPC cells rely on AR activity for survival and proliferation. With advances in immunotherapy and fluid biopsies for cancer management, expression systems specific for both AR-positive and -negative PCa are required for virus-based vaccines and cell imaging. To target both AR-responsive and non-responsive cells, we developed a three-step transcriptional amplification (3STA) system based on the progression elevated gene-3 (
) promoter named
-3STA. Notably, we report on different genetic modifications that significantly improved PEG3 promoter's strength in PCa cells. Adenoviruses incorporating
promoter with and without transcriptional amplification systems were generated. The potential of
-3STA to target PCa cells was then evaluated in vitro and in vivo in androgen-responsive and non-responsive PCa cell lines.
-3STA was shown to be active in all PCa cell lines and not regulated by androgens, and its activity was amplified 97-fold compared to that of a non-amplified promoter. The
-3STA system can thus be used to target advanced AR+ and AR- cells for imaging or immunovirotherapy in advanced PCa.
BackgroundTumour 18F-FDG-uptake is of prognostic value in high-risk and metastatic prostate cancer (PCa). The aim of this study is to investigate the underlying glucose metabolism mechanisms of ...18F-FDG-uptake on PET/CT imaging in PCa.MethodsRetrospective analysis was conducted for 94 patients diagnosed with a Gleason sum ≥8 adenocarcinoma of the prostate at biopsy between July 2011 and July 2014 who underwent 18F-FDG-PET/CT imaging before radical prostatectomy (RP). 18F-FDG-uptake in primary lesion was measured by a blinded reader using maximum standardised uptake value (SUVmax). GLUT1, GLUT12 and HK2 expression were blindly scored after immunohistochemistry on specimens RP by three pathologists. Correlations between GLUT1, GLUT12 and HK2, and SUVmax were assessed using Spearman’s rank correlation test. Survival probabilities were based on the Kaplan–Meier method.ResultsWith a median follow-up of 4.5 years, 56% (n = 53) of patients had biochemical recurrence (BCR), 7% (n = 7) progressed to castration-resistant prostate cancer (CRPC) disease, 13% (n = 12) developed metastasis and 6% (n = 6) died. Correlation was found between GLUT1 expression and SUVmax level (r = 0.25, p = 0.02). In addition, SUVmax was significantly higher in tumours with high GLUT1 expression (n = 17, 5.74 ± 1.67) than tumours with low GLUT1 expression (n = 71, 2.68 ± 0.31, p = 0.004). Moreover, a significant association was found between GLUT1 expression levels and SUVmax level (p = 0.005), lymph node status (p = 0.05), volume of cancer (p = 0.01), CRPC disease progression (p = 0.02) and metastasis development (p = 0.04). No significant difference between GLUT12 and HEX2 expression and SUVmax have been found.ConclusionsGLUT1 expression in PCa tumours correlates with 18F-FDG-uptake and poor prognostic factors. These results suggest that this transporter is involved in the molecular mechanism of 18F-FDG-uptake in high-risk PCa and raise interest in targeting metabolic dependencies of PCa cells as a selective anticancer strategy.
Tumor‐associated macrophages (TAMs) support tumor progression within the tumor microenvironment (TME). Many questions remain as to the origin, development, and function of TAMs within the prostate ...TME. Evaluation of TAMs in prostate cancer (PCa) patients identified the immunosuppressive TAM marker CD163 in adjacent normal epithelium as an independent predictor of metastases or PCa death. Flow cytometry analyses identified prostate TAMs as frequently expressing both proinflammatory M1 (CCR7+) and immunosuppressive M2 (CD163+) markers. In vitro, we demonstrate PCa cells similarly subvert human M1 macrophages toward a mixed M1/M2 macrophage phenotype favoring tumor growth. Further the cytokine milieu‐induced transition between immunosuppressive M2 to proinflammatory M1 (M2→M1) macrophages is abrogated by the presence of PCa cells. RNA sequencing suggests alterations in chemokine expression in prostate TAMs due to the presence of PCa cells. Together, our results suggest that prostate TAMs originate from inflammatory infiltrating macrophages, which are then reprogrammed mainly by PCa cells, but also the cytokine milieu. A better understanding of this subversion of macrophages within the prostate may lead to novel treatment strategies.
Our results demonstrate that mixed inflammatory and immunosuppressive macrophages found in the prostate develop because of prostate cancer contact. The presence of these macrophages in adjacent normal epithelium portends worse long‐term clinical outcomes for prostate cancer patients, highlighting the importance to develop effective strategies against their development.
In this paper, we present a review of recent advances in wrapper feature selection techniques for attack detection and classification, applied in intrusion detection area. Due to the quantity of ...published papers in this area, it is difficult to ascertain the level of current research in wrapper feature selection techniques. Moreover, due to the wide variety of techniques and datasets, is difficult to identify relevant characteristics among them, regard it architecture, performance, advantages and issues. The reported results frequently are shown in heterogeneous way, as there are several metrics to measure the classification quality. From our review, we propose a classification taxonomy of the wrapper feature selection techniques in intrusion detection area, considering design, rationale, technical characteristics and common evaluation metrics. Also we consider a description of the common metrics and a brief discussion about the attack scenarios reported in this review. At the end of this work, we show the coverage of existing research, open challenges and new directions.
•A review of techniques for wrapper feature selection for classify attacks algorithms.•A classification taxonomy of wrapper feature selection techniques for IDS.•A start point to new researches, in wrapper feature selection perspective for IDS.
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