MGI Pharma-SuperGen in Cancer-Drug Deal  NEW YORK (Reuters) - MGI Pharma Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=MOGN.O target=/stocks/quickinfo/fullquote"&gt;MOGN.O&lt;/A&gt; will spend up  to \$85 million for a stake in SuperGen Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=SUPG.O target=/stocks/quickinfo/fullquote"&gt;SUPG.O&lt;/A&gt; and global  rights to develop and sell SuperGen's experimental drug for an  often-fatal cancer of the bone marrow, the companies said on  Wednesday.