So far, at least 44 cases of lesions—about a third of them known to be malignant—have been identified in 21 species of chondrichthyan (the class of jawed and finned vertebrates that include sharks, rays, and skates), as marine biologist Charlie Huveneers and colleagues report in a paper published last year.

But such tumors are rare, it seems—or at least hard to find.

Even after Huveneers, who runs the Southern Shark Ecology Group lab at Australia’s Flinders University, and a team of Australian and American scientists managed to biopsy one funky-looking mass in a shark’s lower jaw—the researchers snagged the tissue from a free-swimming, 14-foot great white using a souped-up harpoon (the ultimate outpatient procedure)—it was hard to determine whether that tissue was cancerous or not. (The team’s best guess is that it was benign.)

And thus, the belief persists: Sharks, if not quite immune to cancer, appear somehow resistant to it.

The support for this theory isn’t just the absence of evidence (the lack of shark sightings at the cancer clinic). It’s also biological. Shark cartilage is avascular: It doesn’t have blood vessels winding through it. What’s more, over the past few decades, research teams have isolated proteins that appear to inhibit the creation of blood vessels, a process known as angiogenesis. Given that cancerous tumors need blood to grow and spread (and, indeed, a hallmark of cancer is the ability to recruit blood vessels through protein signaling), the fact that shark cartilage is apparently anti-angiogenic is tantalizing.

Now, to ratchet this tantalization (<< real word) to Shark Week-degree, there’s more: Several research studies have found that isolated shark proteins do appear to inhibit cancer cell growth in Petri dishes.

But NOT in human cancer patients, sadly. It doesn’t work, folks. In one controlled study after another, shark cartilage extracts have not reversed or halted the disease. Nor have these compounds worked in animal models. (The National Cancer Institute has a great, up-to-date, and comprehensive summary of the efforts here.) Ingesting the stuff, moreover, might even harm you—to say nothing of the sharks themselves.

And that brings up a great challenge for medical science, particularly since the dawn of the Internet and the muddy dusk of social media. While there’s nothing wrong with pursuing such natural-world clues through experimental science—this process, after all, has yielded medicines from penicillin to the cancer drug Taxol—there is the ever-present danger that desperate patients will cling to the clues without following the evidence to its conclusion (and that wily marketers will help them do it).

If Shark Week teaches us anything, it is that hype begets hype. That’s great for TV ratings, surely; not so great for medicine.

One can’t tell, perhaps, from a cladogram, but in the kingdom of medical manias, shark cartilage and snake oil are first cousins.

The news below.

DIGITAL HEALTH

KKR to buy WebMD for $2.8 billion. Private equity giant KKR is snapping up WebMD, the online portal where you can scope out diseases and possible symptoms, for $2.8 billion. The deal comes after WebMD shopped around for potential buyers. The site attracts some 70 million unique visitors every month. (Fortune)

Helix pitches a one-stop personal genomics marketplace. Helix is setting out with a rather unique approach to the red-hot personalized genomics field. The company wants to become a one-stop shop where you send in a DNA swab sample and then can have that information be processed by third-party companies. Helix will also provide resources via partners, such as genetic counseling, that medical experts have argued are key when parsing genetic data.

INDICATIONS

Democrats have a new (old) plan to combat high drug prices. As part of a campaign strategy heading into next year's Congressional midterm elections, the Democratic Party has released a new policy platform it's calling a "Better Deal." One major plank in this political rebranding effort: tackling the high price of prescription drugs. But it's mostly a rehashing of old ideas that various Democrats have previously proposed, including an independent federal agency as an "enforcer" of sorts that can levy fines on drug companies that have exorbitant price hikes, as well as allowing Medicare to directly negotiate drug prices with manufacturers.

Mitsubishi Tanabe snaps up NeuroDerm for $1.1 billion. Mitsubishi Tanabe has reached a deal to purchase NeuroDerm for $1.1 billion. The latter, an Israeli biotech, has a Parkinson's disease drug that's currently in late-stage clinical trials and could reach the U.S. market in 2019.

Samsung Bioepis, Merck to provide hefty price cut to J&J's Remicade. Johnson & Johnson's top-selling product, Remicade (used to treat conditions like rheumatoid arthritis), is about to get a lot more competition. South Korean firm Samsung Bioepis and partner U.S. pharma giant Merck are launching a generic copycat, or "biosimilar," of the treatment at a 35% discount to branded Remicade. That's the heftiest discount in the U.S. market by a biosimilar drug to date and could eat away at the multibillion-dollar treatment's market share. However, there's also a chance that doctors and patients may be wary of switching over to a new treatment, especially since biosimilars haven't been in the U.S. market for very long.

THE BIG PICTURE

The Senate will vote on some kind of health care bill tomorrow but Senators don't know what it is. There's not a whole lot to add to that. As I reported last week, there are several versions of health care legislation floating around the Senate right now, including a tweaked version of the Better Care Reconciliation Act. It's completely unclear which bill will actually be vote on or whether or not it would have the votes to pass. It's also unclear whether a failed vote would end the "repeal-and-replace" movement and lead Senate Republicans to work with Democrats to shore up the very real problems with Obamacare's marketplaces. Stay tuned.

Medicare-for-all will soon face a big political test. On the flip side, Vermont's Sen. Bernie Sanders will soon release a revised version of a "Medicare-for-all" bill that would theoretically serve as a vehicle that leads to single payer health care. This plan is, of course, doomed in Congress. But it's meant to provide a political test of just how much closer Democrats have moved to embracing the policy. Several have embraced the idea; but the devil will ultimately be in the details, as single payer may take many different iterations and would likely come with some extravagant (and politically tricky) costs. (Vox)

REQUIRED READING

The Justice Department May Be Planning a Marijuana Crackdown, by Chris Morris

Something Big Brother Would Love? A Company Will Implant Microchips in Employees, by Barb Darrow

BMW Denies Collusion Allegations, Says It Didn't Cheat Emissions Standards, by Lucinda Shen

You've Never Heard of HNA Group. Here's Why You Will, by Vivienne Walt