DNA Damage and Repair Biomarkers in Cervical Cancer Patients Treated with Neoadjuvant Chemotherapy: An Exploratory Analysis.

Abstract

Cervical cancer cells commonly harbour a defective G1/S checkpoint owing to the interaction of viral oncoproteins with p53 and retinoblastoma protein. The activation of the G2/M checkpoint may thus become essential for protecting cancer cells from genotoxic insults, such as chemotherapy. In 52 cervical cancer patients treated with neoadjuvant chemotherapy, we investigated whether the levels of phosphorylated Wee1 (pWee1), a key G2/M checkpoint kinase, and γ-H2AX, a marker of DNA double-strand breaks, discriminated between patients with a pathological complete response (pCR) and those with residual disease. We also tested the association between pWee1 and phosphorylated Chk1 (pChk1), a kinase acting upstream Wee1 in the G2/M checkpoint pathway. pWee1, γ-H2AX and pChk1 were retrospectively assessed in diagnostic biopsies by immunohistochemistry. The degrees of pWee1 and pChk1 expression were defined using three different classification methods, i.e., staining intensity, Allred score, and a multiplicative score. γ-H2AX was analyzed both as continuous and categorical variable. Irrespective of the classification used, elevated levels of pWee1 and γ-H2AX were significantly associated with a lower rate of pCR. In univariate and multivariate analyses, pWee1 and γ-H2AX were both associated with reduced pCR. Internal validation conducted through a re-sampling without replacement procedure confirmed the robustness of the multivariate model. Finally, we found a significant association between pWee1 and pChk1. The message conveyed by the present analysis is that biomarkers of DNA damage and repair may predict the efficacy of neoadjuvant chemotherapy in cervical cancer. Further studies are warranted to prospectively validate these encouraging findings.

• Authors: Patrizia Vici, Simonetta Buglioni, Domenico Sergi, Laura Pizzuti, Luigi Di Lauro, Barbara Antoniani, Francesca Sperati, Irene Terrenato, Mariantonia Carosi, Teresa Gamucci, Rosanna Dattilo, Monica Bartucci, Cristina Vincenzoni, Luciano Mariani, Enrico Vizza, Giuseppe Sanguineti, Angiolo Gadducci, Ilio Vitale, Maddalena Barba, Ruggero De Maria, Marcella Mottolese, Marcello Maugeri-Saccà
• Journal: PloS one (PLoS One) Vol. 11 Issue 3 Pg. e0149872 ( 2016) ISSN: 1932-6203 [Electronic] United States
• PMID: 26930412 (Publication Type: Journal Article)

Chemical References

• Biomarkers
• Cell Cycle Proteins
• H2AX protein, human
• Histones
• Nuclear Proteins
• Protein-Tyrosine Kinases
• WEE1 protein, human

Topics

• Biomarkers (analysis)
• Cell Cycle Proteins (analysis)
• Cervix Uteri (metabolism, pathology)
• DNA Damage
• DNA Repair
• Female
• G2 Phase Cell Cycle Checkpoints
• Histones (analysis)
• Humans
• Neoadjuvant Therapy
• Nuclear Proteins (analysis)
• Phosphorylation
• Protein-Tyrosine Kinases (analysis)
• Treatment Outcome
• Uterine Cervical Neoplasms (genetics, pathology, therapy)