Investors in Geron ( GERN) -- the stock market's largest player in embryonic stem cell research -- could feel good long before the company discovers any miracle cures.

In the eyes of some, in fact, Geron seems to be dropping hints that it's doing well already. Experts point to two looming events, both set for June, as signs of a possible breakout.

First, Geron will follow through on a promise made months ago to establish the exercise price on 4.125 million warrants for its stock. The warrants, issued in December and February, will be priced based on the stock's value during a narrow trading window ending June 12. Holders can cash in those warrants, beginning June 13, by paying 120% of the average stock price during the previous five sessions, with an upper limit set at $12.14 a share.

Geron's stock, while lifted a week ago by exposure in a prominent Barron's article, fetches just $7.18 a share right now.

"Are those warrant holders keeping a lid on the price right now?" asks Robert Lawton, managing partner of New York's Catoosa Fund. "I can think of 4.125 million reasons why they might."

Lawton, for one, has never seen a company arrange to price warrants during a specific period months after their grant date. When questioned by, Geron itself declined to explain the arrangement or identify who the warrant holders might be. Meanwhile, partly because of this odd scenario, Lawton's firm has invested heavily in Geron -- a biotechnology company that it likes anyway -- in anticipation of a quick return.

"I have seldom directed my firms to take significant long positions in the biotech sector," Lawton admits. But we "have found some significant success on those rare occasions when we have done so."

Meanwhile, Lawton wonders if the warrant pricing period was established with some measure of forethought. Importantly, he notes, that pricing period starts just ahead of a medical conference featuring a key update on the company's cancer drug.

For its part, Geron recently gave investors some reason for hope.

"I can tell you that we are proceeding well," Geron CEO Thomas Okarma assured during the company's first-quarter conference call. But "the real interesting activity or information about the drug ... we are going to reserve for the presentation in June -- which will be an important milestone in the development of this drug."

At that conference, Geron will offer widely anticipated updates on GRN163L -- an agent thought to attack the enzyme needed for cancer stem cells to thrive -- for the treatment of leukemia and solid tumors. By now, the company has discovered evidence of the drug's safety and its ability to shrink myeloma stem cells already.

"GRN163L may have the potential to cure (multiple myeloma) by targeting the cancer stem cells," Rodman & Renshaw analyst Ren Benjamin explained earlier this month. Thus, "encouraged by the potential of eliminating cancer stem cells, the company plans to initiate two GRN163L phase II trials in 2Q/3Q07" to expand tests on myeloma and treat a common type of lung cancer.

Around that same timeframe, Geron plans to launch clinical trials of a new cancer vaccine. The company's vaccine program, which has led to a partnership with heavyweight drug-maker Merck ( MRK), has offered some hope for the prevention of prostate cancer already.

Geron now wishes to replicate the success seen in its early prostate cancer studies, targeting myeloma this time around.

"What we have demonstrated in the prostate cancer trials is really robust and reproducible cellular immune responses to the vaccine that generate killer T-cells that kill the patient's tumor," Okarma stated during the company's latest conference call. "This occurs reproducibly throughout the patient population; it is not anecdotal, and it is not one out of 10 patients.

"This is completely different from the vast majority of the more advanced cancer vaccine programs" currently underway.

Experts look for some preliminary results on Geron's myeloma vaccine, as well as fuller results on GRN163L, by the end of the year.

After that, in a groundbreaking study, Geron plans to use embryonic stem cells for the treatment of damaged spinal cords. Already, the company's technique has scored banner headlines -- and attention by 60 Minutes -- because it enabled partially paralyzed rats to start walking again.

Lawton views those looming human trials as perhaps "the sexiest aspect" of the entire Geron story. In a cover story published last week, Barron's took some notice of that coming study -- and the dashing scientist behind it -- as well.

"If there's a face from stem-cell research that's made for primetime, it's the one belonging to Hans Keirstead," Barron's reported, noting that a Calvin Klein-clad Keirstead has already been hailed as something of a miracle worker in a publication of Men's Vogue. "Based on his research, Geron is applying to the FDA Food and Drug Administration to begin ... potentially the first government-approved test using human embryonic stem cells.

"That would be a key milestone" for the company.

But at the same time, Barron's noted, investors have assigned Geron a handsome value already. Geron boasts a market capitalization of half-a-billion dollars, despite its faraway cures, although more than one-third of that does appear on its balance sheet as cash. Yet Geron's other assets could be worth far more. Notably, thanks to a prescient move about a decade ago, the company holds valuable -- if hotly contested -- patents that give it vast control over embryonic stem cell treatments in the U.S.

Still, Benjamin sees no reason for investors to make their move right now.

"We are maintaining our market-perform/speculative-risk rating on Geron based on the company's current valuation," wrote Benjamin, whose firm makes a market in the company's securities. "While we acknowledge that Geron is developing new modalities of treatment that address large areas of unmet clinical need -- and, therefore, may deserve to trade at a premium to its peers -- we await additional clinical data and peer-reviewed publications, as well as additional clarity regarding the timing of the company's clinical programs, before re-evaluating our rating of the company."

Meanwhile, however, some investors have decided to pounce on the stock already. During the fourth quarter, when Geron issued a big block of warrants, Rock Hill Investment Management bought so much stock in Geron that it emerged as the company's second-largest shareholder. Indeed, a Nasdaq filing indicates, Rock Hill owns far more common stock in Geron than it does in all other companies combined.

Lawton believes there is a reason why Rock Hill has placed that huge bet on Geron. He points to Dendreon ( DNDN), which briefly soared despite questions about the effectiveness of its own prostate cancer vaccine, for comparison. Dendreon, hit by a devastating regulatory ruling last week, has since crashed.

But Lawton feels that Geron is, by far, the better play.

"All Dendreon did is discover a drug that might extend lives for four months," Lawton says. "If Geron has discovered a cancer-fighting agent that works -- and really prolongs life -- then, in my opinion, it's a $50 stock."