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EX-21.1 - EX-21.1 - CALLISTO PHARMACEUTICALS INCa2203096zex-21_1.htm
EX-31.2 - EX-31.2 - CALLISTO PHARMACEUTICALS INCa2203096zex-31_2.htm
EX-31.1 - EX-31.1 - CALLISTO PHARMACEUTICALS INCa2203096zex-31_1.htm
EX-32.2 - EX-32.2 - CALLISTO PHARMACEUTICALS INCa2203096zex-32_2.htm
EX-32.1 - EX-32.1 - CALLISTO PHARMACEUTICALS INCa2203096zex-32_1.htm
10-K - 10-K - CALLISTO PHARMACEUTICALS INCa2203096z10-k.htm

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Exhibit 23

Consent of Independent Registered Public Accounting Firm

Callisto Pharmaceuticals, Inc.
New York, New York

        We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (No. 333-119648 and 333-130716) of Callisto Pharmaceuticals, Inc. and Subsidiaries (a development stage company) (the "Company") of our report dated March 31, 2011, relating to the consolidated financial statements which appear in this Form 10-K. Our report on the consolidated financial statements contains an explanatory paragraph regarding the Company's ability to continue as a going concern.

/s/ BDO USA, LLP

New York, New York
March 31, 2011




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Consent of Independent Registered Public Accounting Firm