Researchers in London report in the Journal of Clinical Pathology that expression of Ki-67, a protein that is present during active phases of the cell cycle, is a moderate marker for human papillomavirus infection in penile squamous cell carcinoma. The researchers examined 148 formalin-fixed, paraffin-embedded penile squamous cell carcinoma samples for Ki-67 expression and presence of HPV. They found that Ki-67 was strongly expressed in nearly 40 percent of the samples and that Ki-67 expression was "positively correlated with high-risk HPV," and with tumor grade. "High Ki-67 immunoexpression could be an indicator, but not a definitive predictor of high-risk HPV infection in PSCC," the researchers write, adding that expression does not correlate with lymph node metastasis, cancer-specific survival, or overall survival.
Also in the Journal of Clinical Pathology, researchers led by the University of Vienna's Sebastian Schoppmann write that the human homolog of CUL-4, which is important in DNA replication in Caenorhabditis elegans, is associated with the development and progression of ovarian carcinoma. CUL-4 is known to interact with cell cycle regulators like p53 and p21. The researchers studied CUL-4, p53, and p21 protein expression in 140 human epithelial ovarian tumor samples, and found that CUL-4 overexpression is associated with overall and disease-free survival in invasive carcinoma. "Our results show that CUL-4 is associated with the malignant potential of ovarian tumors. It might also play a relevant role in the progression of ovarian carcinoma, warranting further investigations," the researchers write, adding that "interestingly, no association of CUL-4 with p53 and p21 expression was found."