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CONTACTS:
LORUS THERAPEUTICS INC.                     CANADIAN MEDIA CONTACT:                    US MEDIA CONTACT
Corporate Communications                    Eliza Walsh                                Jennifer Taylor
Grace Tse                                   Mansfield Communications Inc.              Mansfield Communications Inc.
Tel: (416) 798-1200 ext. 380                Tel: (416) 599-0024                        Tel: (212) 370-5045
Email:  ir@lorusthera.com                   Email:  eliza@mcipr.com                    Email:  jennifer@mcipr.com
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   LORUS THERAPEUTICS SPONSORS INTERNATIONAL LUNG CANCER SCREENING CONFERENCE
               -Lorus to present GTI-2040 studies on lung cancer -


TSX:     LOR
OTC BB:  LORFF

TORONTO, CANADA, OCTOBER 24, 2003 - Lorus Therapeutics Inc. ("Lorus") will be
presenting data on the company's lung cancer research and drug development
program at the Ninth International Conference on Screening for Lung Cancer at
the University of Miami, Jackson Memorial Hospital, Miami, Florida from October
24-26, 2003. Lorus is a corporate sponsor of the conference and will give a
presentation with an abstract entitled "GTI-2040, an antisense oligonucleotide
targeting the R2 component of human ribonucleotide reductase, displays broad
spectrum anti-tumor activity."

The oral presentation will give a brief overview of recent preclinical and
clinical studies of GTI-2040 with a focus on experiments that support the
therapeutic application of GTI-2040 for treatment of lung cancer. GTI-2040
decreases the expression of the R2 component of ribonucleotide reductase, an
essential enzyme for DNA synthesis, resulting in decreased cell growth and
proliferation. Consistent with this model of how GTI-2040 functions, treatment
of human lung cancer cells with GTI-2040 specifically decreases R2 expression
with a concomitant decrease in cell proliferation. Furthermore, GTI-2040
inhibits the growth of human lung tumors implanted in mice. These results
support the expansion of clinical trials to include combinations of GTI-2040
with standard chemotherapeutic drugs for the treatment of lung cancer.

"Lorus is sponsoring this conference because we have a commitment to supporting
leading edge research that may translate into a greater understanding of how to
diagnose and treat cancer," said Dr. Jim Wright, CEO of Lorus. "Fostering an
exchange of information and ideas among researchers is a valuable part of
medical research which leads to breakthroughs in understanding disease
development and progression. This understanding is an important step towards
designing better treatment strategies."

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GTI-2040 is Lorus' lead antisense drug in the clinic, and is currently in
multiple Phase II clinical trials including a U.S. National Cancer Institute
sponsored trial against non-small cell lung cancer in combination with docetaxel
at the Princess Margaret Hospital in Toronto.

About Lorus

Lorus is a biopharmaceutical company focused on the research and development of
cancer therapies. Lorus' goal is to capitalize on its research, pre-clinical,
clinical and regulatory expertise by developing new drug candidates that can be
used, either alone, or in combination, to successfully manage cancer. Through
its own discovery efforts and an active acquisition and in-licensing program,
Lorus is building a portfolio of promising anti-cancer drugs. Late-stage
clinical developments and marketing will be done in cooperation with strategic
pharmaceutical partners. Founded in 1986, Lorus Therapeutics Inc. is a public
company listed on the Toronto Stock Exchange under the symbol LOR, and on the
OTC BB exchange under the symbol LORFF.

Except for historical information, this press release contains forward-looking
statements, which reflect the Company's current expectation regarding future
events. These forward-looking statements involve risks and uncertainties, which
may cause actual results to differ materially from those statements. Those risks
and uncertainties include, but are not limited to, changing market conditions,
the successful and timely completion of clinical studies, the establishment of
corporate alliances, the impact of competitive products and pricing, new product
development, uncertainties related to the regulatory approval process, and other
risks detailed from time-to-time in the Company's ongoing quarterly filings,
annual information form, annual reports and 20-F filings.

Lorus Therapeutics Inc.'s press releases are available through the Company's
Internet site: http://www.lorusthera.com.