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Chen Z, Forman LW, Miller KA, English B, Takashima A, Bohacek RA, Williams RM, Faller DV. Protein kinase Cδ inactivation inhibits cellular proliferation and decreases survival in human neuroendocrine tumors. Endocr Relat Cancer 2011; 18:759-71. [PMID: 21990324 PMCID: PMC3527126 DOI: 10.1530/erc-10-0224] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The concept of targeting cancer therapeutics toward specific mutations or abnormalities in tumor cells, which are not found in normal tissues, has the potential advantages of high selectivity for the tumor and correspondingly low secondary toxicities. Many human malignancies display activating mutations in the Ras family of signal-transducing genes or over-activity of p21(Ras)-signaling pathways. Carcinoid and other neuroendocrine tumors have been similarly demonstrated to have activation of Ras signaling directly by mutations in Ras, indirectly by loss of Ras-regulatory proteins, or via constitutive activation of upstream or downstream effector pathways of Ras, such as growth factor receptors or PI(3)-kinase and Raf/mitogen-activated protein kinases. We previously reported that aberrant activation of Ras signaling sensitizes cells to apoptosis when the activity of the PKCδ isozyme is suppressed and that PKCδ suppression is not toxic to cells with normal levels of p21(Ras) signaling. We demonstrate here that inhibition of PKCδ by a number of independent means, including genetic mechanisms (shRNA) or small-molecule inhibitors, is able to efficiently and selectively repress the growth of human neuroendocrine cell lines derived from bronchopulmonary, foregut, or hindgut tumors. PKCδ inhibition in these tumors also efficiently induced apoptosis. Exposure to small-molecule inhibitors of PKCδ over a period of 24 h is sufficient to significantly suppress cell growth and clonogenic capacity of these tumor cell lines. Neuroendocrine tumors are typically refractory to conventional therapeutic approaches. This Ras-targeted therapeutic approach, mediated through PKCδ suppression, which selectively takes advantage of the very oncogenic mutations that contribute to the malignancy of the tumor, may hold potential as a novel therapeutic modality.
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Rath CM, Janto B, Earl J, Ahmed A, Hu FZ, Hiller L, Dahlgren M, Kreft R, Yu F, Wolff JJ, Kweon HK, Christiansen MA, Håkansson K, Williams RM, Ehrlich GD, Sherman DH. Meta-omic characterization of the marine invertebrate microbial consortium that produces the chemotherapeutic natural product ET-743. ACS Chem Biol 2011; 6:1244-56. [PMID: 21875091 DOI: 10.1021/cb200244t] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In many macroorganisms, the ultimate source of potent biologically active natural products has remained elusive due to an inability to identify and culture the producing symbiotic microorganisms. As a model system for developing a meta-omic approach to identify and characterize natural product pathways from invertebrate-derived microbial consortia, we chose to investigate the ET-743 (Yondelis) biosynthetic pathway. This molecule is an approved anticancer agent obtained in low abundance (10(-4)-10(-5) % w/w) from the tunicate Ecteinascidia turbinata and is generated in suitable quantities for clinical use by a lengthy semisynthetic process. On the basis of structural similarities to three bacterial secondary metabolites, we hypothesized that ET-743 is the product of a marine bacterial symbiont. Using metagenomic sequencing of total DNA from the tunicate/microbial consortium, we targeted and assembled a 35 kb contig containing 25 genes that comprise the core of the NRPS biosynthetic pathway for this valuable anticancer agent. Rigorous sequence analysis based on codon usage of two large unlinked contigs suggests that Candidatus Endoecteinascidia frumentensis produces the ET-743 metabolite. Subsequent metaproteomic analysis confirmed expression of three key biosynthetic proteins. Moreover, the predicted activity of an enzyme for assembly of the tetrahydroisoquinoline core of ET-743 was verified in vitro. This work provides a foundation for direct production of the drug and new analogues through metabolic engineering. We expect that the interdisciplinary approach described is applicable to diverse host-symbiont systems that generate valuable natural products for drug discovery and development.
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Cava MP, Lakshmikantham M, Hoffmann R, Williams RM. R. B. Woodward’s unfinished symphony: designing organic superconductors (1975–79). Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.05.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Vincent G, Williams RM. Corrigendum: Asymmetric Total Synthesis of (−)-Cribrostatin 4 (Renieramycin H). Angew Chem Int Ed Engl 2011. [DOI: 10.1002/anie.201190074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Finefield JM, Kato H, Greshock TJ, Sherman DH, Tsukamoto S, Williams RM. Biosynthetic studies of the notoamides: isotopic synthesis of stephacidin A and incorporation into notoamide B and sclerotiamide. Org Lett 2011; 13:3802-5. [PMID: 21714564 DOI: 10.1021/ol201284y] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The advanced natural product stephacidin A is proposed as a biosynthetic precursor to notoamide B in various Aspergillus species. Doubly (13)C-labeled racemic stephacidin A was synthesized and fed to cultures of the terrestrial-derived fungus, Aspergillus versicolor NRRL 35600, and the marine-derived fungus, Aspergillus sp. MF297-2. Analysis of the metabolites revealed enantiospecific incorporation of intact (-)-stephacidin A into (+)-notoamide B in Aspergillus versicolor and (+)-stephacidin A into (-)-notoamide B in Aspergillus sp. MF297-2. (13)C-Labeled sclerotiamide was also isolated from both fungal cultures.
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Finefield JM, Sherman DH, Tsukamoto S, Williams RM. Studies on the biosynthesis of the notoamides: synthesis of an isotopomer of 6-hydroxydeoxybrevianamide E and biosynthetic incorporation into notoamide J. J Org Chem 2011; 76:5954-8. [PMID: 21504234 DOI: 10.1021/jo200218a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
6-Hydroxydeoxybrevianamide E is proposed as a biosynthetic precursor to several advanced metabolites isolated from both marine-derived Aspergillus sp. and a terrestrial-derived Aspergillus versicolor. To verify the role of this reverse-prenylated indole alkaloid as an intermediate along the biosynthetic pathway, [(13)C](2)-[(15)N]-6-hydroxydeoxybrevianamide E was synthesized and fed to Aspergillus versicolor. Analysis of the metabolites showed incorporation of the intermediate only into the natural product notoamide J.
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Williams RM. Natural products synthesis: enabling tools to penetrate Nature's secrets of biogenesis and biomechanism. J Org Chem 2011; 76:4221-59. [PMID: 21438619 PMCID: PMC3174107 DOI: 10.1021/jo2003693] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Selected examples from our laboratory of how synthetic technology platforms developed for the total synthesis of several disparate families of natural products was harnessed to penetrate biomechanistic and/or biosynthetic queries is discussed. Unexpected discoveries of biomechanistic reactivity and/or penetrating the biogenesis of naturally occurring substances were made possible through access to substances available only through chemical synthesis. Hypothesis-driven total synthesis programs are emerging as very useful conceptual templates for penetrating and exploiting the inherent reactivity of biologically active natural substances. In many instances, new enabling synthetic technologies were required to be developed. The examples demonstrate the often untapped richness of complex molecule synthesis to provide powerful tools to understand, manipulate and exploit Nature's vast and creative palette of secondary metabolites.
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Rafferty RJ, Williams RM. Synthetic Studies on the Ambiguine Family of Alkaloids: Construction of the ABCD Ring System. Tetrahedron Lett 2011; 52:2037-2040. [PMID: 21516192 DOI: 10.1016/j.tetlet.2010.09.086] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
A racemic synthesis of the ABCD ring core of the ambiguines that preserves the tertiary alcohol has been accomplished in convergent synthesis in 10 synthetic steps, in an overall yield of 46% from commercially available 4-bromoindole and m-methylanisole.
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Sunderhaus JD, Sherman DH, Williams RM. Studies on the Biosynthesis of the Stephacidin and Notoamide Natural Products: A Stereochemical and Genetic Conundrum. Isr J Chem 2011; 51:442-452. [PMID: 21818159 PMCID: PMC3148524 DOI: 10.1002/ijch.201100016] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a bicyclo[2.2.2]diazaoctane core. Biosynthetically, this bicyclic core is believed to be the product of an intermolecular Diels- Alder (IMDA) cycloaddition of an achiral azadiene. Since all of the natural products in this family have been isolated in enantiomerically pure form to date, it is believed that an elusive Diels-Alderase enzyme mediates the IMDA reaction. Adding further intrigue to this biosynthetic puzzle is the fact that several related Aspergillus fungi produce a number of metabolites with the opposite absolute configuration, implying that these fungi have evolved enantiomerically distinct Diels-Alderases. We have undertaken a program to identify every step in the biogenesis of the stephacidins and notoamides, and by combining the techniques of chemical synthesis and biochemical analysis we have been able to identify the two prenyltransferases involved in the early stages of the stephacidin and notoamide biosyntheses. This has allowed us to propose a modified biosynthesis for stephacidin A, and has brought us closer to our goal of finding evidence for, or against, the presence of a Diels-Alderase in this biosynthetic pathway.
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Ding Y, de Wet JR, Cavalcoli J, Li S, Greshock TJ, Miller KA, Finefield JM, Sunderhaus JD, McAfoos TJ, Tsukamoto S, Williams RM, Sherman DH. Genome-based characterization of two prenylation steps in the assembly of the stephacidin and notoamide anticancer agents in a marine-derived Aspergillus sp. J Am Chem Soc 2011; 132:12733-40. [PMID: 20722388 DOI: 10.1021/ja1049302] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a core bicyclo[2.2.2]diazaoctane ring system. These bioactive fungal secondary metabolites have a range of unusual structural and stereochemical features but their biosynthesis has remained uncharacterized. Herein, we report the first biosynthetic gene cluster for this class of fungal alkaloids based on whole genome sequencing of a marine-derived Aspergillus sp. Two central pathway enzymes catalyzing both normal and reverse prenyltransfer reactions were characterized in detail. Our results establish the early steps for creation of the prenylated indole alkaloid structure and suggest a scheme for the biosynthesis of stephacidin and notoamide metabolites. The work provides the first genetic and biochemical insights for understanding the structural diversity of this important family of fungal alkaloids.
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Williams RM, Stille J, Echavarren A, Hendrix J, Albrecht B, Williams R. Discussion Addendum for: 4-Methoxy-4'-nitrophenyl. Recent Advances in the Stille Biaryl Coupling Reaction and Applications in Complex Natural Products Synthesis. ORGANIC SYNTHESES; AN ANNUAL PUBLICATION OF SATISFACTORY METHODS FOR THE PREPARATION OF ORGANIC CHEMICALS 2011; 88:197-201. [PMID: 21960729 PMCID: PMC3181114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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McAfoos TJ, Li S, Tsukamoto S, Sherman DH, Williams RM. STUDIES ON THE BIOSYNTHESIS OF THE STEPHACIDINS AND NOTOAMIDES. TOTAL SYNTHESIS OF NOTOAMIDE S. HETEROCYCLES 2010; 82:461-472. [PMID: 21796227 PMCID: PMC3143024 DOI: 10.3987/com-10-s(e)19] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Notoamide S has been suggested to be the final common precursor between two different Aspergillus sp. fungal strains before diverging to form enantiomerically opposite natural products (+)- and (-)-stephacidin A and (+)- and (-)-notoamide B. The synthesis of notoamide S comes from the coupling of N-Fmoc proline with a 6-hydroxy-7-prenyl-2-reverse prenyl tryptophan derivative that was synthesized via a late stage Claisen rearrangement from a 6-propargyl-2-reverse prenylated indole.
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Namba K, Inai M, Sundermeier U, Greshock TJ, Williams RM. Synthetic Studies on Palau'amine. Construction of the Cyclopentane Core via an Asymmetric 1,3-Dipolar Cycloaddition. Tetrahedron Lett 2010; 51:6557-6559. [PMID: 21286237 PMCID: PMC3030269 DOI: 10.1016/j.tetlet.2010.10.037] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The cyclopentane core of palau'amine has been constructed in optically pure form through the use of an asymmetric azomethine ylid [1,3]-dipolar cycloaddition reaction.
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English BJ, Williams RM. A divergent strategy for the synthesis of secologanin derived natural products. J Org Chem 2010; 75:7869-76. [PMID: 20964396 PMCID: PMC3037978 DOI: 10.1021/jo101775n] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The syntheses of D,L-geissoschizol, D,L-corynantheidol, D,L-dihydrocorynantheol, D,L-protoemetinol, and D,L-3-epi-protoemetinol have been accomplished from a single synthetic intermediate.
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Reynolds CA, Oyama MA, Rush JE, Rozanski EA, Singletary GE, Brown DC, Cunningham SM, Fox PR, Bond B, Adin DB, Williams RM, MacDonald KA, Malakoff R, Sleeper MM, Schober KE, Petrie JP, Hogan DF. Perceptions of Quality of Life and Priorities of Owners of Cats with Heart Disease. J Vet Intern Med 2010; 24:1421-6. [PMID: 20738770 DOI: 10.1111/j.1939-1676.2010.0583.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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92
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Finefield JM, Williams RM. Synthesis of notoamide J: a potentially pivotal intermediate in the biosynthesis of several prenylated indole alkaloids. J Org Chem 2010; 75:2785-9. [PMID: 20359229 DOI: 10.1021/jo100332c] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An efficient total synthesis of notoamide J, a new prenylated indole alkaloid and potential biosynthetic precursor, is described herein. Starting from L-proline and a substituted tryptophan derivative, this synthesis also employs an oxidation and pinacol rearrangement for the formation of the oxindole in the final step.
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Bowers AA, Greshock TJ, West N, Estiu G, Schreiber SL, Wiest O, Williams RM, Bradner JE. Synthesis and conformation-activity relationships of the peptide isosteres of FK228 and largazole. J Am Chem Soc 2010; 131:2900-5. [PMID: 19193120 DOI: 10.1021/ja807772w] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The peptide isosteres (10 and 11) of the naturally occurring and potent histone deacetylase (HDAC) inhibitors FK228 and largazole have been synthesized and evaluated side-by-side with FK228, largazole, and SAHA for inhibition of the class I HDACs 1, 2, 3, and 6.
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Williams RM, Deeb A, Ong KK, Bich W, Murgatroyd PR, Hughes IA, Acerini CL. Insulin sensitivity and body composition in children with classical and nonclassical congenital adrenal hyperplasia. Clin Endocrinol (Oxf) 2010; 72:155-60. [PMID: 19508608 DOI: 10.1111/j.1365-2265.2009.03587.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Reduced insulin sensitivity and increased fat mass have been reported in children and adults with congenital adrenal hyperplasia (CAH). To understand the potential mechanisms underlying these differences, we assessed insulin sensitivity and body composition in children with classical or nonclassical (late-presenting) CAH compared with normal controls. SUBJECTS AND METHODS Thirty-seven children with CAH (26 classical and 11 nonclassical) median (range) age 9.4 year (0.5-15.8) were compared with 41 healthy control children age 11.0 year (3.2-17.1). All children had an overnight fasting blood sample and body composition assessed by DEXA. Pubertal children (14 CAH and 19 controls) also had an oral glucose tolerance test. Classical and nonclassical CAH groups were each compared with controls, adjusting for age, gender and pubertal status. Results Classical CAH children had more fat mass than controls (P = 0.03), while nonclassical CAH children had more lean mass (P = 0.006) and higher systolic blood pressure (P = 0.003) than control children. Among pubertal children, nonclassical CAH children had higher mean insulin (0-120 min; P = 0.04), stimulated insulin (0-30 min; P = 0.02), 120 min insulin (P = 0.004) and 120 min glucose levels (P = 0.03) than controls, but no difference in disposition index. DISCUSSION Greater body fat in classical (early-presenting) CAH children could reflect the effects of lifetime glucocorticoid therapy. In contrast, the greater lean mass and parameters of insulin resistance in nonclassical (late-presenting) CAH children likely indicate the adverse metabolic effects of prolonged postnatal androgen excess.
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Subramanian V, Williams RM, Boger DL, Luger K. Methods to characterize the effect of DNA-modifying compounds on nucleosomal DNA. Methods Mol Biol 2010; 613:173-192. [PMID: 19997884 DOI: 10.1007/978-1-60327-418-0_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Eukaryotic DNA forms a complex with an equal mass of proteins to form chromatin. To fully understand the action of DNA-reactive antitumor antibiotics in the cell, their effect must be studied in a chromatin context. In particular, it is of interest to investigate how the distortion of DNA, in the context of a nucleosome, affects the action of drugs with either monoalkylation or crosslinking activity, and how modified DNA is assembled into chromatin. Here, we present experimental approaches that allow one to compare the effect of such drugs on free DNA and nucleosomes. We find significant differences that likely arise from the different geometry of nucleosomal DNA compared to free DNA and also find that drug-mediated DNA crosslinking affects nucleosome assembly.
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Miller KA, Williams RM. Synthetic approaches to the bicyclo[2.2.2]diazaoctane ring system common to the paraherquamides, stephacidins and related prenylated indole alkaloids. Chem Soc Rev 2009; 38:3160-74. [PMID: 19847349 PMCID: PMC2839869 DOI: 10.1039/b816705m] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The bicyclo[2.2.2]diazaoctane ring system is common to a number of highly biologically active secondary metabolites isolated from numerous species of fungi. In this tutorial review, we describe the varied synthetic approaches that have been employed to construct this ring system in the course of recent total synthesis endeavors, and this review should be of interest to synthetic organic chemists and natural product chemists. Detailed herein are a number of synthetic disconnections including intramolecular S(N)2' cyclizations, biomimetic Diels-Alder reactions, radical cyclizations, and cationic cascade reactions.
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97
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Burnett CM, Williams RM. Asymmetric Synthesis of the Core of AMPTD, the Key Amino Acid of Microsclerodermins F-I. Tetrahedron Lett 2009; 50:5449-5451. [PMID: 20191096 DOI: 10.1016/j.tetlet.2009.06.144] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a stereoselective synthesis of the five consecutive stereocenters of AMPTD in seven steps. Highlights include an Evans glycolate aldol reaction, the use of a Weinreb amide as an aldehyde masking group, and a Mannich reaction with an Ellman-type chiral sulfimine.
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98
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Newkirk TL, Bowers AA, Williams RM. Discovery, biological activity, synthesis and potential therapeutic utility of naturally occurring histone deacetylase inhibitors. Nat Prod Rep 2009; 26:1293-320. [PMID: 19779641 DOI: 10.1039/b817886k] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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99
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Gubler DA, Williams RM. Synthetic Studies Towards the Mitomycins: Construction of the Tetracyclic Core via a Reductive Aminocyclization Reaction. Tetrahedron Lett 2009; 50:4265-4267. [PMID: 20161278 PMCID: PMC2702872 DOI: 10.1016/j.tetlet.2009.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The tetracyclic core of the mitomycin family of natural products has been formed in one step from an acyclic precursor via a reductive aminocyclization reaction. Additionally, the 8-membered benzazocine can be prepared without the need for prior activation of the aniline. Construction of a mitomycin K analogue lacking the C9a methoxy moiety is also reported herein.
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Williams RM, Westmorland MG, Lin CA, Schmuck G, Creen M. Effectiveness of workplace rehabilitation interventions in the treatment of work-related low back pain: A systematic review. Disabil Rehabil 2009; 29:607-24. [PMID: 17453982 DOI: 10.1080/09638280600841513] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE A systematic review was conducted to evaluate the effectiveness of workplace rehabilitation interventions for injured workers with low back pain (LBP). METHOD MEDLINE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), EMBASE, and AMED (Allied and Complementary Medicine) were searched from 1982 to 2005 for peer-reviewed studies of rehabilitation interventions that were provided at the workplace to workers with musculoskeletal work-related LBP. Methodological quality appraisal and data extraction were conducted by five reviewers. RESULTS Of a total of 1,224 articles that were identified by the search, 15 articles, consisting of 10 studies, were of sufficient quality to be included in the review. The best evidence was that clinical interventions with occupational interventions as well as early return to work/modified work interventions were effective in returning workers to work faster, reducing pain and disability, and decreasing the rate of back injuries. Ergonomic interventions also were found to be effective workplace interventions. CONCLUSION The need for further research in this area is necessary to reduce the burden of back pain on employees and their families, employers, and the health care system.
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