Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.

[EX Q]: Bone, as well as the lung and liver, is among the sites of predilection for cancer metastasis. The bone stores large amounts of growth factors such as insulin-like growth factors and transforming growth factor-b, and provides fertile soil for metastatic cancer cells by continuously releasing these bone-stored growth factors, which are a consequence of osteoclastic bone resorption. Metastatic cancer cells in turn produce osteoclast-stimulating cytokines such as parathyroid hormone-related protein( PTH-rP), prostaglandin E2.(PGE2), and various interleukins(ILs). These cancer-produced osteoclast-stimulating cytokines bind to their cognitive receptors and promote the expression of ligands for the receptor activators of nuclear factor kB (RANKL)in osteoblasts. RANKL then binds to its receptor RANK, expressed in pre-osteoclasts, stimulates mature osteoclast formation, and subsequently, osteoclastic bone resorption. This vicious cycle between metastatic cancer cells and osteoclasts is critical to the development and progression of bone metastases. In addition, it is likely that metastatic cancer cells are influenced by bone environments(or niche)and acquire additional capacities such as an epithelial-mesenchymal transition(EMT), allowing them to be resistant to chemotherapy or apoptosis, to survive in a dormant state, or to aggressively spread to distant organs including lung and liver. Thus, the bone can serve as transit port. Disrupting this cycle by inhibiting osteoclastic bone resorption, antagonizing bone-derived growth factors, and neutralizing RANKL or PTH-rP, should be a promising therapeutic intervention for bone metastases. Bisphosphonates(BP)are specific inhibitors of osteoclasts, and have been shown to significantly reduce skeletal-related events(SRE)associated with bone metastasis. Denosumab is a neutralizing monoclonal antibody to RANKL and has recently been found to inhibit SRE more effectively than BP. Further understanding of the crosstalk communication between metastatic cancer cells and bone at the molecular level should lead us to design novel, more effective and specific treatments for cancer patients with bone metastases.
[EX A]: To the ligand of which receptors does Denosumab (Prolia) bind?

[EX Q]: In melanoma, transition to the vertical growth phase is the critical step in conversion to a deadly malignant disease. Here, we offer the first evidence that an antioxidant enzyme has a key role in this transition. We found that the antioxidant enzyme peroxiredoxin-2 (Prx2) inversely correlated with the metastatic capacity of human melanoma cells. Silencing Prx2 expression stimulated proliferation and migration, whereas ectopic expression of Prx2 produced the opposite effect. Mechanistic investigations indicated that Prx2 negatively regulated Src/ERK activation status, which in turn fortified adherens junctions function by increasing E-cadherin expression and phospho-Y654-dependent retention of -catenin in the plasma membrane. In murine melanoma cells, Prx2 silencing enhanced lung metastasis in vivo. Interestingly, the natural compound gliotoxin, which is known to exert a Prx-like activity, inhibited proliferation and migration as well as lung metastasis of Prx2-deficient melanoma cells. Overall, our findings reveal that Prx2 is a key regulator of invasion and metastasis in melanoma, and also suggest a pharmacologic strategy to effectively decrease deadly malignant forms of this disease.
[EX A]: What type of enzyme is peroxiredoxin 2 (PRDX2)?

[EX Q]: Coming off their home win over the Lions, the 49ers flew to the Louisiana Superdome for a Week 4 duel with the New Orleans Saints. In the first quarter, the Niners struck first as kicker Joe Nedney got a 47-yard field goal. In the second quarter, the Saints took the lead with QB Drew Brees completing a 5-yard and a 33-yard TD pass to WR Lance Moore. San Francisco would answer with Nedney's 49-yard field goal, yet New Orleans replied with Brees' 47-yard TD pass to WR Robert Meachem. In the third quarter, the 49ers tried to rally as Nedney kicked a 38-yard field goal. However, in the fourth quarter, the Saints continued to pull away as RB Deuce McAllister got a 1-yard TD run. The Niners tried to rally as QB J.T. O'Sullivan completed a 5-yard TD pass to WR Isaac Bruce, yet New Orleans sealed the win with kicker Martin Gramatica nailing a 31-yard field goal.
[EX A]:
Which player got the Saints on the board?