An Assessment of TLR4 and TOPK/PRPK Signaling in Sun Damaged Human Skin Acutely Exposed to Solar Simulated Light

August 1, 2023 updated by: University of Arizona
The purpose of this project is to obtain clinical data, including skin samples, that will help investigators evaluate changes occurring in sun damaged human skin as a result of light that simulates sun exposure (Solar Simulated Light). Of specific interest are the molecular targets for cancer prevention. Molecular targets are the parts of the body's cells that have been shown to play a role in causing or preventing cancer and which scientists seek to affect in a way that may slow or eliminate the development of cancer.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

The aim of this study is to assess TLR4 and TOPK/PRPK signaling in sun damaged human skin acutely exposed to solar simulated light and to validate this clinical model prior to intervention with therapeutic skin cancer prevention approaches.

Acute solar simulated light exposure will be evaluated in sun damaged skin to determine the level of activation of the targeted pathways using reverse-phase protein array (LCM-RPPA) analysis and immunohistochemistry (IHC).

Study Type

Interventional

Enrollment (Actual)

31

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Arizona
      • Tucson, Arizona, United States, 85724
        • University of Arizona

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 90 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Healthy individuals 18 years of age or older.
  • Individuals with mild, moderate, or severe photodamage [1] of the skin on the forearms (also Appendix C) and Fitzpatrick skin type II or III (21 CFR 352.72).
  • Females of childbearing potential will need to undergo a pregnancy test at the enrollment visit, after administration of the ICF and before exposure to SSL. Premenopausal female subjects must use an effective method of birth control (such as oral contraceptives, consistent use of barrier contraceptives, IUD, or other proven method of birth control) during study participation. For the purposes of this study, a woman will be considered postmenopausal if any of the following criteria are met: (1) she has had prior bilateral oophorectomy; (2) she is over the age of 60 years; or (3) she is under the age of 60 years and has not had a menstrual period in 12 or more months in the absence of chemotherapy, tamoxifen, toremifene, or ovarian suppression.
  • Individuals who are willing to limit sun exposure to the body during the study period and who agree to wear protective clothing when they are outdoors.
  • Individuals who have the ability to understand and willingness to sign an informed consent before initiation of study procedures, after the nature of the study is explained to them and they have had the opportunity to ask any questions.

Exclusion Criteria:

  • Individuals with any inflammation or irritation of the skin at the test areas, or any skin conditions felt by the study medical provider to contraindicate enrollment. This includes, but is not limited to, psoriasis or atopic dermatitis within the test areas.
  • Test area is defined as the 6 mm areas of skin that is exposed to SSL and will be biopsied.
  • Individuals with a history of any untreated skin cancer, melanocytic lesions, or actinic keratoses in the test areas are ineligible. History of such conditions at a body site other than the test areas is not exclusionary if in the opinion of the study medical provider it will not pose a risk to the subject.
  • Individuals who have had invasive cancer, chemotherapy or radiation therapy within five years of study enrollment
  • Individuals who are immunosuppressed by virtue of medication or disease. This includes AIDS patients, subjects taking oral steroids, and subjects on immunosuppressants/immunomodulators (cyclosporine, chemotherapeutic agents, or biologic therapy), as determined by the examining study medical provider.
  • Individuals with serious intercurrent illness including, but not limited to, ongoing or active infection, psychiatric illness, or other situations that in the opinion of the examining study medical provider would limit compliance or interfere with the study regimen.
  • Individuals who have used photosensitizing drugs (see Appendix for examples) within 30 days of enrollment, or who will be using a photosensitizing drug during the time of the study, will not be eligible. Subjects may be reconsidered for eligibility 30 days after the last dose of such medications.
  • Individuals who have used any topical medication other than emollients or sunscreen/sunblock on the test area within 30 days prior to study enrollment. If a study participant requires topical medication to the test area during the study, they will be withdrawn from the study.
  • Individuals who have used retinoids, steroids, 5-fluorouracil, Levulan, Vaniqua (eflornithine), Solaraze, or Imiquimod (Aldara®) anywhere on the body within 30 days prior to study enrollment. Subjects may be reconsidered for eligibility 30 days after the last topical treatment with such medications.
  • Individuals must not take mega-doses of vitamins. Mega-doses are defined as more than 5 capsules of standard multivitamins daily or more than the Tolerable Upper Intake Levels of Vitamins, as defined by the Institute of Medicine, National Academy of Sciences. Such vitamin therapy must be discontinued at least 30 days prior to study entry.
  • Individuals with a history of deliberate natural or artificial sun exposure (tanning) within 30 days of study enrollment are not eligible.
  • Individuals with Fitzpatrick skin type I are ineligible, as the proposed SSL dose could result in a burn of greater than mild severity.
  • Individuals with Fitzpatrick skin type IV, V or VI are ineligible, as they are unlikely to exhibit a salient response in the proposed design.
  • Individuals currently enrolled in or who plan to enroll in another clinical trial. There must be a 30-day period between completing a previous study and enrolling in this study.
  • Individuals with a known allergy to lidocaine are not eligible.
  • Females who are pregnant or nursing.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: TLR4 and TOPK/PRPK Signaling in Sun Damaged Human Skin Acutely Exposed to Solar Simulated Light
We have one arm, which consists of participants with a broad range of sun damage on the forearm. Based on the standardized clinical photodamage scale (Hu C, Curiel-Lewandrowski C. Archives of Dermatology, 2011; 147(1):31-36), we will include mild (N=12), moderate (N=12), and severely (N=12) sun damaged skin.
Acute SSL will be delivered to sun damaged skin at a rate of two-times the minimal erythema dose of each individual subject. Minimal erythema dose is defined as the smallest dose of energy necessary to produce confluent erythema with four distinct borders at 22-26 hours post-exposure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Primary Endpoint: To assess changes in skin cancer signaling pathway activation levels pre-solar simulated light exposure (baseline) and 5hr and 24hr post-solar simulated light exposure in sun damaged skin.
Time Frame: Changes from baseline (pre-SSL exposure) to post-SSL exposure (at 5hr and 24hr post-exposure).
The translational aim of this study is to prospectively assess changes in protein activation associated with skin cancer progression in sun damaged human skin acutely exposed to solar simulated light by determining the level of activation using reverse-phase protein array (LCM-RPPA) analysis. Reverse phase protein microarray will be implemented to evaluate changes in over 100 phosphorylated and total proteins of interest.
Changes from baseline (pre-SSL exposure) to post-SSL exposure (at 5hr and 24hr post-exposure).
To assess changes in skin cancer signaling pathway activation levels pre-solar simulated light exposure (baseline) and 5hr and 24hr post-solar simulated light exposure in sun damaged skin.
Time Frame: Changes from baseline (pre-SSL exposure) to post-SSL exposure (at 5hr and 24hr post-exposure).
The translational aim of this study is to prospectively assess changes in protein activation associated with skin cancer progression in sun damaged human skin acutely exposed to solar simulated light by determining the level of activation using immunohistochemistry. Immunohistochemistry assays will analyze changes in signaling pathway protein expression over time.
Changes from baseline (pre-SSL exposure) to post-SSL exposure (at 5hr and 24hr post-exposure).

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Exploratory Endpoint: To assess the correlation between skin sun damage level and the magnitude of solar simulated light-induced pathway activation.
Time Frame: Baseline (pre-SSL exposure) and post-SSL exposure (at 5hr and 24hr post-exposure).
The exploratory analyses will associate the sun damage score/severity level with analyte activation in the sun damage samples. Based on these analyses, the most appropriate post-solar simulated light time point (per pathway) will be selected based on the combination with the largest effect sizes. Furthermore, an exploratory systems biology analysis will be conducted based on these analyses; one post-SSL time point (per pathway) will be selected for future studies based on the combination with the largest effect sizes.
Baseline (pre-SSL exposure) and post-SSL exposure (at 5hr and 24hr post-exposure).

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Clara Curiel, MD, University of Arizona

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 3, 2020

Primary Completion (Actual)

August 1, 2023

Study Completion (Actual)

August 1, 2023

Study Registration Dates

First Submitted

May 20, 2022

First Submitted That Met QC Criteria

May 25, 2022

First Posted (Actual)

May 31, 2022

Study Record Updates

Last Update Posted (Actual)

August 3, 2023

Last Update Submitted That Met QC Criteria

August 1, 2023

Last Verified

August 1, 2023

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 1907830098
  • P01CA229112 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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