Neprilysin (/ˌnɛprɪˈlaɪsɪn/), also known as membrane metallo-endopeptidase (MME), neutral endopeptidase (NEP), cluster of differentiation 10 (CD10), and common acute lymphoblastic leukemia antigen (CALLA) is an enzyme that in humans is encoded by the MME gene. Neprilysin is a zinc-dependent metalloprotease that cleaves peptides at the amino side of hydrophobic residues and inactivates several peptide hormones including glucagon, enkephalins, substance P, neurotensin, oxytocin, and bradykinin.[1] It also degrades the amyloid beta peptide whose abnormal misfolding and aggregation in neural tissue has been implicated as a cause of Alzheimer's disease. Synthesized as a membrane-bound protein, the neprilysin ectodomain is released into the extracellular domain after it has been transported from the Golgi apparatus to the cell surface.
Neprilysin is expressed in a wide variety of tissues and is particularly abundant in kidney. It is also a common acute lymphocytic leukemia antigen that is an important cell surface marker in the diagnosis of human acute lymphocytic leukemia (ALL). This protein is present on leukemic cells of pre-B phenotype, which represent 85% of cases of ALL.[1]
Hematopoetic progenitors expressing CD10 are considered "common lymphoid progenitors", which means they can differentiate into T, B or natural killer cells.[2] CD10 is of use in hematological diagnosis since it is expressed by early B, pro-B and pre-B lymphocytes, and by lymph node germinal centers.[3] Hematologic diseases in which it is positive include ALL, angioimmunoblastic T cell lymphoma, Burkitt lymphoma, chronic myelogenous leukemia in blast crisis (90%), diffuse large B-cell lymphoma (variable), follicular center cells (70%), hairy cell leukemia (10%), and myeloma (some). It tends to be negative in acute myeloid leukemia, chronic lymphocytic leukemia, mantle cell lymphoma, and marginal zone lymphoma. CD10 is found on non-T ALL cells, which derive from pre-B lymphocytes, and in germinal center-related non-Hodgkin lymphoma such as Burkitt lymphoma and follicular lymphoma, but not on leukemia cells or lymphomas, which originate in more mature B cells.[4]
Neprilysin-deficient knockout mice show both Alzheimer's-like behavioral impairment and amyloid-beta deposition in the brain,[5] providing strong evidence for the protein's association with the Alzheimer's disease process. Because neprilysin is thought to be the rate-limiting step in amyloid beta degradation,[6] it has been considered a potential therapeutic target; compounds such as the peptide hormonesomatostatin have been identified that increase the enzyme's activity level.[7] One hypothesis for the strong dependence of Alzheimer's incidence on age focuses on the declining production of somatostatin in the brains of elderly people, which thus depresses the activity of neprilysin and promotes aggregation of unprocessed amyloid beta.[8] Declining neprilysin activity with increasing age may also be explained by oxidative damage, known to be a causative factor in Alzheimer's disease; higher levels of inappropriately oxidized neprilysin have been found in Alzheimer's patients compared to cognitively normal elderly people.[9]
Associations have been observed between neprilysin expression and various types of cancer; however, the relationship between neprilysin expression and carcinogenesis remains obscure. In cancer biomarker studies, the neprilysin gene is often referred to as CD10 or CALLA. In some types of cancer, such as metastaticcarcinoma and some advanced melanomas, neprilysin is overexpressed;[12] in other types, most notably lung cancers, neprilysin is downregulated, and thus unable to modulate the pro-growth autocrine signaling of cancer cells via secreted peptides such as mammalian homologs related to bombesin.[13]
Some plant extracts (methanol extracts of Ceropegia rupicola, Kniphofia sumarae, Plectranthus cf barbatus, and an aqueous extract of Pavetta longiflora) were found able to inhibit the enzymatic activity of neutral endopeptidase.[14]
CD10+ diffuse large B cell lymphoma (CD10+ DLBLC)[17]
Marker for germinal center phenotype (CD10, HGAL, BCL6, CD38) are considered a favorable prognostic factor,[18][19] but CD10+, BCL2+ tumors could have poorer survival.[20] For some authors, CD10 expression in DLBCL does not influence survival.[21]
CD10+ distinguishes renal cell carcinoma, conventional type with eosinophilic morphology from its mimickers. Chromophobe carcinoma and oncocytoma are CD10−.[26]
CD10 expression is strongly correlated with high tumor grade and stage in urothelial carcinoma of the bladder. CD10 may be associated with tumor progression in bladder cancer pathogenesis.[31]
In other tumors
CD10 expression might be one of the characteristics of müllerian system-derived neoplastic mesenchymal cells.[32]
↑"Human T, B, natural killer, and dendritic cells arise from a common bone marrow progenitor cell subset". Immunity. 3 (4): 459–73. Oct 1995. doi:10.1016/1074-7613(95)90175-2. PMID7584137.
↑Singh C (2011-02-25). "CD10". CD Markers. PathologyOutlines.com, Inc.
↑Madani R, Poirier R, Wolfer DP, Welzl H, Groscurth P, Lipp HP, Lu B, El Mouedden M, Mercken M, Nitsch RM, Mohajeri MH (December 2006). "Lack of neprilysin suffices to generate murine amyloid-like deposits in the brain and behavioral deficit in vivo". J. Neurosci. Res. 84 (8): 1871–8. doi:10.1002/jnr.21074. PMID16998901.
↑Iwata N, Tsubuki S, Takaki Y, Watanabe K, Sekiguchi M, Hosoki E, Kawashima-Morishima M, Lee HJ, Hama E, Sekine-Aizawa Y, Saido TC (February 2000). "Identification of the major Abeta1-42-degrading catabolic pathway in brain parenchyma: suppression leads to biochemical and pathological deposition". Nat. Med. 6 (2): 143–50. doi:10.1038/72237. PMID10655101.
↑Iwata N, Higuchi M, Saido TC (November 2005). "Metabolism of amyloid-beta peptide and Alzheimer's disease". Pharmacol. Ther. 108 (2): 129–48. doi:10.1016/j.pharmthera.2005.03.010. PMID16112736.
↑Hama E, Saido TC (2005). "Etiology of sporadic Alzheimer's disease: somatostatin, neprilysin, and amyloid beta peptide". Med. Hypotheses. 65 (3): 498–500. doi:10.1016/j.mehy.2005.02.045. PMID15921860.
↑Wang DS, Iwata N, Hama E, Saido TC, Dickson DW (October 2003). "Oxidized neprilysin in aging and Alzheimer's disease brains". Biochem. Biophys. Res. Commun. 310 (1): 236–41. doi:10.1016/j.bbrc.2003.09.003. PMID14511676.
↑ 10.010.1Sahli S, Stump B, Welti T, Schweizer WB, Diederich R, Blum-Kaelin D, Aebi JD, Böhm HJ (April 2005). "A New Class of Inhibitors for the Metalloprotease Neprilysin Based on a Central Imidazole Scaffold". Helvetica Chimica Acta. 88 (4): 707–730. doi:10.1002/hlca.200590050.
↑ 11.011.1Oefner C, Roques BP, Fournie-Zaluski MC, Dale GE (February 2004). "Structural analysis of neprilysin with various specific and potent inhibitors". Acta Crystallogr. D. 60 (Pt 2): 392–6. doi:10.1107/S0907444903027410. PMID14747736.
↑Berglund M, Thunberg U, Amini RM, Book M, Roos G, Erlanson M, Linderoth J, Dictor M, Jerkeman M, Cavallin-Ståhl E, Sundström C, Rehn-Eriksson S, Backlin C, Hagberg H, Rosenquist R, Enblad G (2005). "Evaluation of immunophenotype in diffuse large B-cell lymphoma and its impact on prognosis". Mod. Pathol. 18 (8): 1113–20. doi:10.1038/modpathol.3800396. PMID15920553.
↑Xu Y, McKenna RW, Molberg KH, Kroft SH (2001). "Clinicopathologic analysis of CD10+ and CD10- diffuse large B-cell lymphoma. Identification of a high-risk subset with coexpression of CD10 and bcl-2". Am. J. Clin. Pathol. 116 (2): 183–90. doi:10.1309/J7RN-UXAY-55GX-BUNK. PMID11488064.
↑Fabiani B, Delmer A, Lepage E, Guettier C, Petrella T, Brière J, Penny AM, Copin MC, Diebold J, Reyes F, Gaulard P, Molina TJ (2004). "CD10 expression in diffuse large B-cell lymphomas does not influence survival". Virchows Arch. 445 (6): 545–51. doi:10.1007/s00428-004-1129-7. PMID15517363.
↑Baseggio L, Traverse-Glehen A, Berger F, Ffrench M, Jallades L, Morel D, Goedert G, Magaud JP, Salles G, Felman P (2011). "CD10 and ICOS expression by multiparametric flow cytometry in angioimmunoblastic T-cell lymphoma". Mod. Pathol. 24 (7): 993–1003. doi:10.1038/modpathol.2011.53. PMID21499231.
↑Yuan CM, Vergilio JA, Zhao XF, Smith TK, Harris NL, Bagg A (2005). "CD10 and BCL6 expression in the diagnosis of angioimmunoblastic T-cell lymphoma: utility of detecting CD10+ T cells by flow cytometry". Hum. Pathol. 36 (7): 784–91. doi:10.1016/j.humpath.2005.05.008. PMID16084948.
↑Attygalle AD, Diss TC, Munson P, Isaacson PG, Du MQ, Dogan A (2004). "CD10 expression in extranodal dissemination of angioimmunoblastic T-cell lymphoma". Am. J. Surg. Pathol. 28 (1): 54–61. doi:10.1097/00000478-200401000-00005. PMID14707864.
↑Cook JR, Craig FE, Swerdlow SH (2003). "Benign CD10-positive T cells in reactive lymphoid proliferations and B-cell lymphomas". Mod. Pathol. 16 (9): 879–85. doi:10.1097/01.MP.0000084630.64243.D1. PMID13679451.
↑Yasir S, Herrera L, Gomez-Fernandez C, Reis IM, Umar S, Leveillee R, Kava B, Jorda M (2012). "CD10+ and CK7/RON- immunophenotype distinguishes renal cell carcinoma, conventional type with eosinophilic morphology from its mimickers". Appl. Immunohistochem. Mol. Morphol. 20 (5): 454–61. doi:10.1097/PAI.0b013e31823fecd3. PMID22417859.
↑ 27.027.1Notohara K, Hamazaki S, Tsukayama C, Nakamoto S, Kawabata K, Mizobuchi K, Sakamoto K, Okada S (2000). "Solid-pseudopapillary tumor of the pancreas: immunohistochemical localization of neuroendocrine markers and CD10". Am. J. Surg. Pathol. 24 (10): 1361–71. doi:10.1097/00000478-200010000-00005. PMID11023097.
↑Córdoba A, Guerrero D, Larrinaga B, Iglesias ME, Arrechea MA, Yanguas JI (2009). "Bcl-2 and CD10 expression in the differential diagnosis of trichoblastoma, basal cell carcinoma, and basal cell carcinoma with follicular differentiation". Int. J. Dermatol. 48 (7): 713–7. doi:10.1111/j.1365-4632.2009.04076.x. PMID19570076.
↑ 32.032.1Mikami Y, Hata S, Kiyokawa T, Manabe T (2002). "Expression of CD10 in malignant müllerian mixed tumors and adenosarcomas: an immunohistochemical study". Mod. Pathol. 15 (9): 923–30. doi:10.1097/01.MP.0000026058.33869.DB. PMID12218209.
↑McCluggage WG, Sumathi VP, Maxwell P (2001). "CD10 is a sensitive and diagnostically useful immunohistochemical marker of normal endometrial stroma and of endometrial stromal neoplasms". Histopathology. 39 (3): 273–8. doi:10.1046/j.1365-2559.2001.01215.x. PMID11532038.
↑Kabbinavar FF, Hambleton J, Mass RD, Hurwitz HI, Bergsland E, Sarkar S (2005). "Combined analysis of efficacy: the addition of bevacizumab to fluorouracil/leucovorin improves survival for patients with metastatic colorectal cancer". J. Clin. Oncol. 23 (16): 3706–12. doi:10.1200/JCO.2005.00.232. PMID15867200.
↑Weinreb I, Cunningham KS, Perez-Ordoñez B, Hwang DM (2009). "CD10 is expressed in most epithelioid hemangioendotheliomas: a potential diagnostic pitfall". Arch. Pathol. Lab. Med. 133 (12): 1965–8. doi:10.1043/1543-2165-133.12.1965. PMID19961253.
↑Jung SM, Kuo TT (2005). "Immunoreactivity of CD10 and inhibin alpha in differentiating hemangioblastoma of central nervous system from metastatic clear cell renal cell carcinoma". Mod. Pathol. 18 (6): 788–94. doi:10.1038/modpathol.3800351. PMID15578072.