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<S>                                          <C>                                              <C>
CONTACTS:
LORUS THERAPEUTICS INC.                      CANADIAN MEDIA CONTACT:                          US MEDIA CONTACT:

Corporate Communications                     Hugh Mansfield                                   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:  hugh@mcipr.com                           E-mail:  jennifer@mcipr.com
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    LORUS THERAPEUTICS ANNOUNCES VIRULIZIN(R) PRESENTATION AT THE 5TH ANNUAL
                  LUSTGARTEN FOUNDATION SCIENTIFIC CONFERENCE

   - Co-sponsored by Dana-Farber Cancer Institute and Harvard Medical School -


TSE:              LOR
OTC BB:           LORFF

TORONTO, JUNE 17, 2003 - Lorus Therapeutics Inc. ("Lorus") announced today that
data on its lead immunotherapeutic anticancer drug Virulizin(R)'s mode of action
was accepted for a presentation at the 5th Annual Lustgarten Foundation
Scientific Conference being held in Boston, Massachusetts on June 16 and 17,
2003. The poster presentation of preclinical and clinical findings is entitled,
'Stimulation of Natural Killer Cell function in Pancreatic Cancer with
Virulizin(R), an Immunotheraepeutic Agent.'

The conference targets researchers and community based oncologists worldwide.
The Lustgarten Foundation for Pancreatic Cancer Research is the largest private
foundation dedicated exclusively to supporting pancreatic cancer research.

"We are pleased to be a part of the Lustgarten Foundation's 5th Annual
Scientific Conference. This is a valuable clinical and scientific event bringing
together clinicians and researchers in an important cause for the improvement of
pancreatic cancer care," said Dr. Jim Wright, chief executive officer, Lorus.
"The Lustgarten Foundation provides scientific and patient care leadership for a
devastating disease where few treatment options exist for patients."

                                     (more)

                                      - 2 -

Virulizin(R) is currently in a pivotal North American Phase III clinical trial
for the first-line treatment of advanced pancreatic cancer in combination with
gemcitabine. Preclinical and earlier clinical studies using Virulizin(R) as a
treatment supported a mechanism of action through enhanced immune cell activity,
including Natural Killer (NK) cell function, across a number of cancer types
including pancreatic cancer.

Recent preclinical studies demonstrate that NK cells infiltrate tumors following
Virulizin(R) treatment. It is believed that low NK cell activity may be a risk
factor for cancer or cancer spread, and a negative prognostic indicator in
pancreatic cancer. Therefore, a drug that stimulates NK cell activity has the
potential to be a valuable anticancer tool. In addition to primary and secondary
endpoints, such as survival and clinical benefit, the current Phase III clinical
trial will also examine NK cell function and other immune parameters as
potential biologic markers of therapeutic response.

The Lustgarten Foundation concentrates its efforts on helping the scientific
community work towards finding a cure for pancreatic cancer. The Foundation has
awarded $9 million in support of promising pancreatic research and has sponsored
four international scientific meetings at leading institutions. The Foundation
also provides patient information through the dissemination of handbooks and a
comprehensive Web site, and promotes pubic awareness of this devastating disease
through a public service announcement campaign featuring former President Jimmy
Carter, who also serves as honorary chairman of the Foundation's corporate
advisory board.

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.


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