title: Prognostic significance of polo-like kinases in retinoblastoma: correlation with patient outcome, clinical and histopathological parameters.
abstract: BACKGROUND
  Retinoblastoma is evolving, but it is still a therapeutic challenge for pediatric oncologists. Polo-like kinases (PLKs) plays an important role in cell cycle events. They play a crucial role in cell proliferation which may lead to tumour formation. The objective of this study is to investigate the role of PLK1 and PLK3 proteins in human retinoblastoma tissues.
  
  
  METHODS
  Non-randomized, prospective study was performed in the Dr R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
  
  
  METHODS
  This study included 74 primary enucleated retinoblastoma tissues.
  
  
  METHODS
  Expression of PLK1 and PLK3 protein were assessed in primary enucleated retinoblastoma tissues by immunohistochemistry and western blotting.
  
  
  METHODS
  Expression of PLK1 and PLK3 protein were correlated with clinical and histopathological parameters, tumour staging and overall survival of patients.
  
  
  RESULTS
  Immunohistochemical results revealed expression of PLK1 in 47/74 (63.51%) cases and PLK3 in 31/74 (41.89%) cases. Western blotting confirmed the immunoreactivity results. Expression of PLK1 showed correlation with poor differentiation and tumour invasion. In addition, PLK1 was statistically significant with massive choroidal invasion, whereas PLK3 did not correlate with any of the clinical or histopathological parameters. There was no statistical correlation in the overall survival of patients with PLK1 and PLK3 expression.
  
  
  CONCLUSIONS
  PLK1 expression was associated with poor tumour differentiation and histopathological high-risk factors. These proteins may be involved in tumorigenesis and progression of disease. These results suggest that PLK1 may act as a potential therapeutic target and a promising marker for developing potent small molecule inhibitors of PLK isoforms in retinoblastoma.
authors.affiliation: Department of Ocular Pathology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Lata
authors.initials: L
authors.lastname: Singh
authors.affiliation: Department of Ophthalmology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Neelam
authors.initials: N
authors.lastname: Pushker
authors.affiliation: Department of Ocular Pathology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Seema
authors.initials: S
authors.lastname: Sen
authors.affiliation: Department of Ocular Pathology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Mithalesh K
authors.initials: MK
authors.lastname: Singh
authors.affiliation: Department of Ocular Pathology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Feeroj A
authors.initials: FA
authors.lastname: Chauhan
authors.affiliation: Department of Ocular Pathology, Dr. R. P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Seema
authors.initials: S
authors.lastname: Kashyap
mesh_terms: D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D015353:Eye Enucleation; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007223:Infant; D008297:Male; D011379:Prognosis; D011446:Prospective Studies; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D019572:Retinal Neoplasms / Q000201:enzymology* / Q000473:pathology; D012175:Retinoblastoma / Q000201:enzymology* / Q000473:pathology; D025521:Tumor Suppressor Proteins; D000097869:Polo-Like Kinase 1; D000097868:Polo-like Kinases
chemical_list: D018797:Cell Cycle Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D025521:Tumor Suppressor Proteins; D000097869:Polo-Like Kinase 1; C486256:PLK3 protein, human; D000097868:Polo-like Kinases
keywords: immunohistochemistry; polo-like kinase; retinoblastoma