# RADIOBIOLOGICAL STUDIES OF HUMAN HYBRID CELL LINES

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA-IRVINE · 1990 · $172,605

## Abstract

The long term objectives of the proposed research are several.  The first
is to gain further understanding of the genetic control of the
radiosensitivity of human cells and how the genetic changes which
accompany neoplastic transformation may effect radiosensitivity.  The
second is to determine radiation-induced genetic changes associated with
the neoplastic transformation of human cells.  The third is to obtain
quantitative information relating to various aspects of radiation-induced
neoplastic transformation of human derived cell lines.  The medical
significance of the proposed research is principally to the fields of
radiation carcinogenesis and radiation therapy.

To approach these long term objectives, we will continue our studies with
well characterized non-tumorigenic and tumorigenic human cell hybrid
lines (HeLa x skin fibroblast).  Furthermore, we will initiate new
studies with human microcell hybrid lines (HeLa plus a single copy of a
human skin fibroblast chromosome, initially chromosome 11 which has been
shown to suppress the tumorigenicity of HeLa cells).

The rationale for the Specific Aims for the proposed funding period is
based on our studies to date.  These aims include (1) examining the cell
cycle dependency of radiosensitivity and DNA damage induction and repair
of both non-tumorigenic and tumorigenic hybrid cells, (2) examining
contribution of PLDR and SLDR to cell survival and neoplastic
transformation for non-tumorigenic cells treated with fractionated and
low dose-rate radiation and (3) isolating and characterizing various
properties radiation-induced neoplastic cells (including probing for loss
of tumor-suppressor gene).  Standard methodologies as well as those
either developed or being developed in the laboratories of the P.I. and
Co-P.I. will be used.  Cell survival will be assessed by colony forming
ability, DNA damage by alkali and neutral elution; neoplastic
transformation by immunoperoxidase assay of expression of tumor
associated antigen, by loss of suppressor gene by RFLP analysis, and by
ability of cells to grow tumors when injected into nude mice.

## Key facts

- **NIH application ID:** 3178140
- **Project number:** 5R01CA039312-05
- **Recipient organization:** UNIVERSITY OF CALIFORNIA-IRVINE
- **SAM.gov UEI:** MJC5FCYQTPE6
- **Principal Investigator:** JOHN L REDPATH
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1990
- **Award amount:** $172,605
- **Award type:** 5
- **Project period:** 1986-03-01 → 1992-02-28

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3178140

## Citation

> US National Institutes of Health, RePORTER application 3178140, RADIOBIOLOGICAL STUDIES OF HUMAN HYBRID CELL LINES (5R01CA039312-05). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3178140. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*