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Roy S, Dukic T, Keepers Z, Bhandary B, Lamichhane N, Molitoris J, Ko YH, Banerjee A, Shukla HD. SOX2 and OCT4 mediate radiation and drug resistance in pancreatic tumor organoids. Cell Death Discov 2024; 10:106. [PMID: 38429272 PMCID: PMC10907757 DOI: 10.1038/s41420-024-01871-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 02/09/2024] [Accepted: 02/14/2024] [Indexed: 03/03/2024] Open
Abstract
Pancreatic cancer has a five-year survival rate of only 10%, mostly due to late diagnosis and limited treatment options. In patients with unresectable disease, either FOLFIRINOX, a combination of 5-fluorouracil (5-FU), oxaliplatin and irinotecan, or gemcitabine plus nab-paclitaxel combined with radiation are frontline standard regimens. However, chemo-radiation therapy has shown limited success because patients develop resistance to chemotherapy and/or radiation. In this study, we evaluated the role of pancreatic cancer stem cells (CSC) using OCT4 and SOX2, CSC markers in mouse pancreatic tumor organoids. We treated pancreatic tumor organoids with 4 or 8 Gy of radiation, 10 μM of 5-FU (5-Fluorouracil), and 100 μM 3-Bromopyruvate (3BP), a promising anti-cancer drug, as a single treatment modalities, and in combination with RT. Our results showed significant upregulation of, OCT4, and SOX2 expression in pancreatic tumor organoids treated with 4 and 8 Gy of radiation, and downregulation following 5-FU treatment. The expression of CSC markers with increasing treatment dose exhibited elevated upregulation levels to radiation and downregulation to 5-FU chemotherapy drug. Conversely, when tumor organoids were treated with a combination of 5-FU and radiation, there was a significant inhibition in SOX2 and OCT4 expression, indicating CSC self-renewal inhibition. Noticeably, we also observed that human pancreatic tumor tissues exhibited heterogeneous and aberrant OCT4 and SOX2 expression as compared to normal pancreas, indicating their potential role in pancreatic cancer growth and therapy resistance. In addition, the combination of 5-FU and radiation treatment exhibited significant inhibition of the β-catenin pathway in pancreatic tumor organoids, resulting in sensitization to treatment and organoid death. In conclusion, our study emphasizes the crucial role of CSCs in therapeutic resistance in PC treatment. We recommend using tumor organoids as a model system to explore the impact of CSCs in PC and identify new therapeutic targets.
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Affiliation(s)
- Sanjit Roy
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Tijana Dukic
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Zachery Keepers
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Binny Bhandary
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Narottam Lamichhane
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jason Molitoris
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Young H Ko
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Aditi Banerjee
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Hem D Shukla
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA.
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Shukla H, Shukla HD, Dukic T, Roy S, Lamichhane N, Molitoris JK, Carrier F, Regine WF. Pancreatic Cancer Derived 3-D Organoids as Clinical Tool to Predict Response to Radiation and Chemo-Radiation Therapy. Int J Radiat Oncol Biol Phys 2023; 117:e259. [PMID: 37784993 DOI: 10.1016/j.ijrobp.2023.06.1211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Pancreatic cancer (PC) is the fourth leading cause of cancer death in both men and women. The standard of care for patients with locally advanced PC of chemotherapy, stereotactic radiotherapy (RT) or chemo-radiation-therapy has shown highly variable and limited success rates. However, three-dimensional (3D) Pancreatic tumor organoids (PTOs) have shown promise to study tumor response to drugs, and emerging treatments under in vitro conditions. We investigated the potential for using 3D organoids to evaluate the precise radiation and drug dose responses of in vivo PC tumors. MATERIALS/METHODS PTOs were created from mouse pancreatic tumor tissues, and their microenvironment was compared to that of in vivo tumors using immunohistochemical staining. The organoids and in vivo PC tumors were treated with fractionated X-ray RT, 3-bromopyruvate (3BP) anti-tumor drug, and with a combination of 3BP + fractionated RT. We quantified treatment response by metabolic imaging and immunofluorescence of αSMA and vimentin markers. RESULTS Pancreatic tumor organoids (PTOs) exhibited a similar fibrotic microenvironment and molecular response (as seen by apoptosis biomarker expression) as in vivo tumors. Untreated tumor organoids and in vivo tumor both exhibited proliferative growth of 6 folds the original size after 10 days, whereas no growth was seen for organoids and in vivo tumors treated with 8 (Gray) Gy of fractionated RT. Tumor organoids showed reduced growth rates of 3.2x and 1.8x when treated with 4 and 6 Gy fractionated RT, respectively. Interestingly, combination of 100 µM of 3BP + 4 Gy of RT showed pronounced growth inhibition as compared to 3-BP alone or 4 Gy of radiation alone. Further, we observed overexpression of OCT-4, SOX2, Nanog cancer stem cell markers (CSC) indicated presence of cancer stem cells in tumor organoids which might have some role in resistance to therapies and recurrence in pancreatic cancer. CONCLUSION PTOs produced a similar microenvironment and exhibited similar growth characteristics as in vivo tumors following treatment, indicating their potential for predicting in vivo tumor sensitivity and response to RT and combined chemo-RT treatments. Cancer stem cells in pancreatic cancer could be playing a role in resistance to therapies and recurrence in pancreatic cancer.
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Affiliation(s)
- H Shukla
- Dept of Radiation Oncology, School of Medicine, University of Maryland, Baltimore, MD
| | - H D Shukla
- 655 West Baltimore Street, Bressler Research Building 8-025, Baltimore, MD
| | - T Dukic
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore MD 21201, Baltimore, MD
| | - S Roy
- 1Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD 21201 2 New G Lab Pharma, 701 East Pratt Street, Columbus Center, Baltimore, MD 21202., Baltimore, MD
| | - N Lamichhane
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD
| | - J K Molitoris
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD
| | - F Carrier
- University of Maryland, Baltimore, MD
| | - W F Regine
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD
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Shukla HD, Dukic T, Roy S, Bhandary B, Gerry A, Poirier Y, Lamichhane N, Molitoris J, Carrier F, Banerjee A, Regine WF, Polf JC. Pancreatic cancer derived 3D organoids as a clinical tool to evaluate the treatment response. Front Oncol 2023; 12:1072774. [PMID: 36713532 PMCID: PMC9879007 DOI: 10.3389/fonc.2022.1072774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 11/29/2022] [Indexed: 01/13/2023] Open
Abstract
Background and purpose Pancreatic cancer (PC) is the fourth leading cause of cancer death in both men and women. The standard of care for patients with locally advanced PC of chemotherapy, stereotactic radiotherapy (RT), or chemo-radiation-therapy has shown highly variable and limited success rates. However, three-dimensional (3D) Pancreatic tumor organoids (PTOs) have shown promise to study tumor response to drugs, and emerging treatments under in vitro conditions. We investigated the potential for using 3D organoids to evaluate the precise radiation and drug dose responses of in vivo PC tumors. Methods PTOs were created from mouse pancreatic tumor tissues, and their microenvironment was compared to that of in vivo tumors using immunohistochemical and immunofluorescence staining. The organoids and in vivo PC tumors were treated with fractionated X-ray RT, 3-bromopyruvate (3BP) anti-tumor drug, and combination of 3BP + fractionated RT. Results Pancreatic tumor organoids (PTOs) exhibited a similar fibrotic microenvironment and molecular response (as seen by apoptosis biomarker expression) as in vivo tumors. Untreated tumor organoids and in vivo tumor both exhibited proliferative growth of 6 folds the original size after 10 days, whereas no growth was seen for organoids and in vivo tumors treated with 8 (Gray) Gy of fractionated RT. Tumor organoids showed reduced growth rates of 3.2x and 1.8x when treated with 4 and 6 Gy fractionated RT, respectively. Interestingly, combination of 100 µM of 3BP + 4 Gy of RT showed pronounced growth inhibition as compared to 3-BP alone or 4 Gy of radiation alone. Further, positive identification of SOX2, SOX10 and TGFβ indicated presence of cancer stem cells in tumor organoids which might have some role in resistance to therapies in pancreatic cancer. Conclusions PTOs produced a similar microenvironment and exhibited similar growth characteristics as in vivo tumors following treatment, indicating their potential for predicting in vivo tumor sensitivity and response to RT and combined chemo-RT treatments.
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Affiliation(s)
- Hem D Shukla
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States,*Correspondence: Hem D Shukla,
| | - Tijana Dukic
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Sanjit Roy
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Binny Bhandary
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Andrew Gerry
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Yannick Poirier
- Division of Medical Physics, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Narottam Lamichhane
- Division of Medical Physics, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Jason Molitoris
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - France Carrier
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Aditi Banerjee
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - William F. Regine
- Division of Translational Radiation Sciences, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Jerimy C. Polf
- Division of Medical Physics, Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD, United States
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Leiser D, Samanta S, Eley J, Strauss J, Creed M, Kingsbury T, Staats PN, Bhandary B, Chen M, Dukic T, Roy S, Mahmood J, Vujaskovic Z, Shukla HD. Role of caveolin-1 as a biomarker for radiation resistance and tumor aggression in lung cancer. PLoS One 2021; 16:e0258951. [PMID: 34762666 PMCID: PMC8584669 DOI: 10.1371/journal.pone.0258951] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 10/10/2021] [Indexed: 01/14/2023] Open
Abstract
Radiation therapy plays a major role in the treatment of lung cancer patients. However, cancer cells develop resistance to radiation. Tumor radioresistance is a complex multifactorial mechanism which may be dependent on DNA damage and repair, hypoxic conditions inside tumor microenvironment, and the clonal selection of radioresistant cells from the heterogeneous tumor site, and it is a major cause of treatment failure in non-small cell lung cancer (NSCLC). In the present investigation caveolin-1 (CAV-1) has been observed to be highly expressed in radiation resistant A549 lung cancer cells. CRISPR-Cas9 knockout of CAV-1 reverted the cells to a radio sensitive phenotype. In addition, CAV-1 overexpression in parental A549 cells, led to radiation resistance. Further, gene expression analysis of A549 parental, radiation resistant, and caveolin-1 overexpressed cells, exhibited overexpression of DNA repair genes RAD51B, RAD18, SOX2 cancer stem cell marker, MMPs, mucins and cytoskeleton proteins in resistant and caveolin-1 over expressed A549 cells, as compared to parental A549 cells. Bioinformatic analysis shows upregulation of BRCA1, Nuclear Excision DNA repair, TGFB and JAK/STAT signaling pathways in radioresistant and caveolin-1 overexpressed cells, which may functionally mediate radiation resistance. Immunohistochemistry data demonstrated heterogeneous expression of CAV-1 gene in human lung cancer tissues, which was analogous to its enhanced expression in human lung cancer cell line model and mouse orthotopic xenograft lung cancer model. Also, TCGA PanCancer clinical studies have demonstrated amplification, deletions and missense mutation in CAV-1 gene in lung cancer patients, and that CAV-1 alteration has been linked to poor prognosis, and poor survival in lung cancer patients. Interestingly, we have also optimized ELISA assay to measure caveolin-1 protein in the blood of A549 radiation resistant human xenograft preclinical mouse model and discovered higher level of caveolin-1 (950 pg/ml) in tumor bearing animals treated with radiation, as compared to xenograft with radiosensitive lung cancer cells (450 pg/ml). Thus, we conclude that caveolin-1 is involved in radio-resistance and contributes to tumor aggression, and it has potential to be used as prognostic biomarker for radiation treatment response, and tumor progression for precision medicine in lung cancer patients.
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Affiliation(s)
- Dominic Leiser
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Santanu Samanta
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - John Eley
- Department of Radiation Oncology, School of Medicine, Vanderbilt University, Nashville, TN, United States of America
| | - Josh Strauss
- Department of Radiation Oncology, School of Medicine, Vanderbilt University, Nashville, TN, United States of America
| | - Michael Creed
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Tami Kingsbury
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Paul N. Staats
- Department of Pathology, University of Maryland, School of Medicine, Baltimore, MD, United States of America
| | - Binny Bhandary
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Minjie Chen
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Tijana Dukic
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Sanjit Roy
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Javed Mahmood
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Zeljko Vujaskovic
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Hem D. Shukla
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, United States of America
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Singh P, Eley J, Saeed A, Bhandary B, Mahmood N, Chen M, Dukic T, Mossahebi S, Rodrigues DB, Mahmood J, Vujaskovic Z, Shukla HD. Effect of hyperthermia and proton beam radiation as a novel approach in chordoma cells death and its clinical implication to treat chordoma. Int J Radiat Biol 2021; 97:1675-1686. [PMID: 34495790 DOI: 10.1080/09553002.2021.1976861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE Chordoma is a locally aggressive tumor that most commonly affects the base of the skull/clivus, cervical, and sacral spine. Conventional radiotherapy (RT), cannot be safely increased further to improve disease control due to the risk of toxicity to the surrounding critical structures. Tumor-targeted hyperthermia (HT) combined with Proton Beam Radiation Therapy (PBRT) is known to act as a potent radiosensitizer in cancer control. In this study, we investigated whether PBRT efficacy for chordoma can be enhanced in combination with HT as a radiosensitizer. MATERIAL AND METHODS Human chordoma cell lines, U-CH2 and Mug-chor1 were treated in vitro with HT followed by PBRT with variable doses. The colony-forming assay was performed, and dose-response was characterized by linear-quadratic model fits. HSP-70 and Brachyury (TBXT) biomarkers for chordoma aggression levels were quantified by western blot analysis. Gene microarray analysis was performed by U133 Arrays. Pathway Analysis was also performed using IPA bioinformatic software. RESULTS Our findings in both U-CH2 and Mug-Chor1 cell lines demonstrate that hyperthermia followed by PBRT has an enhanced cell killing effect when compared with PBRT-alone (p < .01). Western blot analysis showed HT decreased the expression of Brachyury protein (p < .05), which is considered a biomarker for chordoma tumor aggression. HT with PBRT also exhibited an RT-dose-dependent decrease of Brachyury expression (p < .05). We also observed enhanced HSP-70 expression due to HT, RT, and HT + RT combined in both cell lines. Interestingly, genomic data showed 344 genes expressed by the treatment of HT + RT compared to HT (68 genes) or RT (112 genes) as individual treatment. We also identified activation of death receptor and apoptotic pathway in HT + RT treated cells. CONCLUSION We found that Hyperthermia (HT) combined with Proton Beam Radiation (PBRT) could significantly increase chordoma cell death by activating the death receptor pathway and apoptosis which has the promise to treat metastatic chordoma.
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Affiliation(s)
- Prerna Singh
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - John Eley
- Department of Radiation Oncology, School of Medicine, Vanderbilt University, Nashville, TN, USA
| | - Ali Saeed
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Binny Bhandary
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Nayab Mahmood
- College of Information Science, University of Maryland College Park, MD, USA
| | - Minjie Chen
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Tijana Dukic
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Sina Mossahebi
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Dario B Rodrigues
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Javed Mahmood
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Zeljko Vujaskovic
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Hem D Shukla
- Division of Translational Radiation Sciences (DTRS), Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
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Ahlstrom C, Kircher K, Fors C, Dukic T, Patten C, Anund A. Measuring Driver Impairments: Sleepiness, Distraction, and Workload. IEEE Pulse 2012; 3:22-30. [DOI: 10.1109/mpul.2011.2181020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Dukic T, Hanson L, Falkmer T. Effect of drivers' age and push button locations on visual time off road, steering wheel deviation and safety perception. Ergonomics 2006; 49:78-92. [PMID: 16393805 DOI: 10.1080/00207540500422320] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The study examined the effects of manual control locations on two groups of randomly selected young and old drivers in relation to visual time off road, steering wheel deviation and safety perception. Measures of visual time off road, steering wheel deviations and safety perception were performed with young and old drivers during real traffic. The results showed an effect of both driver's age and button location on the dependent variables. Older drivers spent longer visual time off road when pushing the buttons and had larger steering wheel deviations. Moreover, the greater the eccentricity between the normal line of sight and the button locations, the longer the visual time off road and the larger the steering wheel deviations. No interaction effect between button location and age was found with regard to visual time off road. Button location had an effect on perceived safety: the further away from the normal line of sight the lower the rating.
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Affiliation(s)
- T Dukic
- National Institute for Working Life--West, Gothenburg, Sweden.
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Abstract
Although buttons are a frequently used type of control in car interiors, little research has been undertaken on how the usage of buttons affects the visual behaviour of the driver. In this study, the aim was to analyse the effect of push button location and auditory feedback on drivers' visual time off road and safety perception when driving in a real traffic situation. The effect of six button locations (five on the centre stack, one near the gear stick) was tested. Drivers' visual behaviour was studied in real traffic on a motorway. An eye tracking system recorded the visual behaviour of eight drivers who, in 96 repeated trials each, were instructed to press a specific button. Data analysis focused on the drivers' visual time off road and safety perception in relation to the location of the button to be pressed. Auditory feedback did not show a significant effect on visual time off road. The time off road increased significantly as the angle increased between the normal line of sight and button location for the five buttons placed on the centre stack. Results for the button located close to the gear stick, with the highest eccentricity, produced a short time off road. This unexpected finding is discussed in terms of three potential explanations: 1) the role of perceptual discrimination; 2) risk perception; and 3) motor control.
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Affiliation(s)
- T Dukic
- National Institute for Working Life, Gothenburg, Sweden.
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