Serial changes in liquid biopsy-derived variant allele frequency predict immune checkpoint inhibitor responsiveness in the pan-cancer setting.

Major immunotherapy challenges include a limited number of predictive biomarkers and the unusual imaging features post-therapy, such as pseudo-progression, which denote immune infiltrate-mediated tumor enlargement. Such phenomena confound clinical decision-making, since the cancer may eventually regress, and the patient should stay on treatment. We prospectively evaluated serial, blood-derived cell-free DNA (cfDNA) (baseline and 2-3 weeks post-immune checkpoint inhibitors [ICIs]) for variant allele frequency (VAF) and blood tumor mutation burden (bTMB) changes (next-generation sequencing) (N = 84 evaluable patients, diverse cancers).

Analysis of circulating tumor cells derived from advanced gastric cancer.

Studies in circulating tumor cells (CTCs) have proceeded to be accepted as prognostic markers in several types of cancers. But they are still limited because many are mainly from enumeration of CTCs. Here, we tried to evaluate the tumorigenicity of CTCs from advanced gastric cancer patients (n = 42).

TAK-441, a novel investigational smoothened antagonist, delays castration-resistant progression in prostate cancer by disrupting paracrine hedgehog signaling.

Hedgehog (Hh) signaling is a highly conserved intercellular and intracellular communication mechanism that governs organogenesis and is dysregulated in cancers of numerous tissues, including prostate. Up-regulated expression of the Hh ligands, Sonic (Shh) and Desert (Dhh), has been reported in androgen-deprived and castration-resistant prostate cancer (CRPC). In a cohort of therapy naive, short- and long-term neoadjuvant hormone therapy-treated (NHT), and CRPC specimens, we observed elevated Dhh expression predominantly in long-term NHT specimens and elevated Shh expression predominantly in CRPC specimens.

Reactive-site mutants of N-TIMP-3 that selectively inhibit ADAMTS-4 and ADAMTS-5: biological and structural implications.

We have reported previously that reactive-site mutants of N-TIMP-3 [N-terminal inhibitory domain of TIMP-3 (tissue inhibitor of metalloproteinases 3)] modified at the N-terminus, selectively inhibited ADAM17 (a disintegrin and metalloproteinase 17) over the MMPs (matrix metalloproteinases). The primary aggrecanases ADAMTS (ADAM with thrombospondin motifs) -4 and -5 are ADAM17-related metalloproteinases which are similarly inhibited by TIMP-3, but are poorly inhibited by other TIMPs. Using a newly developed recombinant protein substrate based on the IGD (interglobular domain) of aggrecan, gst-IGD-flag, these reactive-site mutants were found to similarly inhibit ADAMTS-4 and ADAMTS-5.

Tenascin-C is an endogenous activator of Toll-like receptor 4 that is essential for maintaining inflammation in arthritic joint disease.

Although there have been major advances in the treatment of rheumatoid arthritis with the advent of biological agents, the mechanisms that drive cytokine production and sustain disease chronicity remain unknown. Tenascin-C (encoded by Tnc) is an extracellular matrix glycoprotein specifically expressed at areas of inflammation and tissue damage in inflamed rheumatoid joints. Here we show that mice that do not express tenascin-C show rapid resolution of acute joint inflammation and are protected from erosive arthritis.

Proteolytic activities of human ADAMTS-5: comparative studies with ADAMTS-4.

Aggrecanases have been characterized as proteinases that cleave the Glu373-Ala374 bond of the aggrecan core protein, and they are multidomain metalloproteinases belonging to the ADAMTS (adamalysin with thrombospondin type 1 motifs) family. The first aggrecanases discovered were ADAMTS-4 (aggrecanase 1) and ADAMTS-5 (aggrecanase 2). They contain a zinc catalytic domain followed by non-catalytic ancillary domains, including a disintegrin domain, a thrombospondin domain, a cysteine-rich domain, and a spacer domain.

Substrate conformation modulates aggrecanase (ADAMTS-4) affinity and sequence specificity. Suggestion of a common topological specificity for functionally diverse proteases.

Protease-substrate interactions are governed by a variety of structural features. Although the substrate sequence specificities of numerous proteases have been established, "topological specificities," whereby proteases may be classified based on recognition of distinct three-dimensional structural motifs, have not. The aggrecanase members of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family cleave a variety of proteins but do not seem to possess distinct sequence specificities.

Structural features of the reprolysin atrolysin C and tissue inhibitors of metalloproteinases (TIMPs) interaction.

Atrolysin C is a P-I snake venom metalloproteinase (SVMP) from Crotalus atrox venom, which efficiently degrades capillary basement membranes, extracellular matrix, and cell surface proteins to produce hemorrhage. The tissue inhibitors of metalloproteinases (TIMPs) are effective inhibitors of matrix metalloproteinases which share some structural similarity with the SVMPs. In this work, we evaluated the inhibitory profile of TIMP-1, TIMP-2, and the N-terminal domain of TIMP-3 (N-TIMP-3) on the proteolytic activity of atrolysin C and analyzed the structural requirements and molecular basis of inhibitor-enzyme interaction using molecular modeling.

Reactive site mutations in tissue inhibitor of metalloproteinase-3 disrupt inhibition of matrix metalloproteinases but not tumor necrosis factor-alpha-converting enzyme.

Tissue inhibitor of metalloproteinase-3 (TIMP-3) is a dual inhibitor of the matrix metalloproteinases (MMPs) and some adamalysins, two families of extracellular and cell surface metalloproteinases that function in extracellular matrix turnover and the shedding of cell surface proteins. The mechanism of inhibition of MMPs by TIMPs has been well characterized, and since the catalytic domains of MMPs and adamalysins are homologous, it was assumed that the interaction of TIMP-3 with adamalysins is closely similar. Here we report that the inhibition of the extracellular region of ADAM-17 (tumor necrosis factor alpha-converting enzyme (TACE)) by the inhibitory domain of TIMP-3 (N-TIMP-3) shows positive cooperativity.

Differential inhibition of membrane type 3 (MT3)-matrix metalloproteinase (MMP) and MT1-MMP by tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-3 rgulates pro-MMP-2 activation.

The membrane type (MT)-matrix metalloproteinases (MMPs) constitute a subgroup of membrane-anchored MMPs that are major mediators of pericellular proteolysis and physiological activators of pro-MMP-2. The MT-MMPs also exhibit differential inhibition by members of the tissue inhibitor of metalloproteinase (TIMP) family. Here we investigated the processing, catalytic activity, and TIMP inhibition of MT3-MMP (MMP-16).

TIMP-3 inhibits aggrecanase-mediated glycosaminoglycan release from cartilage explants stimulated by catabolic factors.

Aggrecanases are considered to play a key role in the destruction of articular cartilage during the progression of arthritis. Here we report that the N-terminal inhibitory domain of tissue inhibitor of metalloproteinases 3 (N-TIMP-3), but not TIMP-1 or TIMP-2, inhibits glycosaminoglycan release from bovine nasal and porcine articular cartilage explants stimulated with interleukin-1alpha or retinoic acid in a dose-dependent manner. This inhibition is due to the blocking of aggrecanase activity induced by the catabolic factors.

Altered proteolytic activities of ADAMTS-4 expressed by C-terminal processing.

ADAMTS-4 (a disintegrin and metalloprotease with thrombospondin motifs) is a multidomain metalloproteinase belonging to the reprolysin family. The enzyme cleaves aggrecan core protein at several sites. Here we report that the non-catalytic ancillary domains of the enzyme play a major role in regulating aggrecanase activity, with the C-terminal spacer domain masking the general proteolytic activity.

Aggrecanases and cartilage matrix degradation.

The loss of extracellular matrix macromolecules from the cartilage results in serious impairment of joint function. Metalloproteinases called 'aggrecanases' that cleave the Glu373-Ala374 bond of the aggrecan core protein play a key role in the early stages of cartilage destruction in rheumatoid arthritis and in osteoarthritis. Three members of the ADAMTS family of proteinases, ADAMTS-1, ADAMTS-4 and ADAMTS-5, have been identified as aggrecanases.

Tissue inhibitor of metalloproteinases-3 induces apoptosis in melanoma cells by stabilization of death receptors.

Tissue inhibitors of metalloproteinases (TIMPs) are important regulators of matrix metalloproteinase (MMP) and adamalysin (ADAM) activity. We have previously shown that adenovirally expressed tissue inhibitor of metalloproteinases-3 (TIMP-3) induces apoptosis in melanoma cells and inhibits growth of human melanoma xenografts. Here, we have studied the role of death receptors in apoptosis of melanoma cells induced by TIMP-3.

RING finger, B-box, and coiled-coil (RBCC) protein expression in branchial epithelial cells of Japanese eel, Anguilla japonica.

An RBCC (RING finger, B-box, and coiled-coil) protein was identified that belongs to the superfamily of zinc-binding proteins and is specifically expressed in the gill of eel, Anguilla japonica. Euryhaline fishes such as eels can migrate between freshwater and seawater, which is considered to be accomplished by efficient remodeling of the architecture and function of the gill, a major osmoregulatory organ. To identify molecules involved in such adaptive changes, we performed differential display using mRNA preparations from freshwater and seawater eel gills and obtained an RBCC clone among several differentially expressed clones.