Researchers develop paste for treatment of radiation dermatitis
By Mark McCarty,
Anyone who has experienced repeated episodes of radiotherapy knows too well the consequences of that exposure, but researchers at the Laura and Isaac Perlmutter Cancer Center (New York) believe they have a solution to the problem of radiation dermatitis, a condition said to affect as many as 95 of every 100 patients undergoing radiotherapy. The study entailed exposing mice to a single dose of 40 Grays, described as roughly equivalent to the dose received by patients whose treatment regimen runs five weeks. An unspecified number of the mice in this experiment were genetically engineered for loss of the adenosine A2A receptor, and half of the mice undergoing irradiation were treated with a topical paste (said to be the subject of a patent) containing an A2A receptor blocker, while the balance were treated with a placebo topical. After roughly four weeks, the non-genetically altered mice receiving the placebo demonstrated double the amount of collagen, skin thickness and fibrosis than was present prior to irradiation, while normal mice on the treatment topical experienced an increase in these characteristics of only about 10 percent. However, the idea of blocking A2A activity was further supported by the fact that genetically engineered mice "developed no skin reaction at all to the radiation," the statement said. The results of this study appear in the January edition of the Journal of the Federation of American Societies for Experimental Biology.
CTC diversity predictive of response
Circulating tumor cells are definitely bad news for prostate cancer patients, but they do say something about a patient's response to two therapies. A recent statement made note of research conducted by scientists at Memorial Sloan Kettering Cancer Center (New York) and Epic Sciences (San Diego) examined more than 9,200 circulating tumor cells (CTCs) drawn from roughly 220 metastatic, castrate-resistant prostate cancer (mCRPC) patients by running those CTCs through Epic's no cell left behind liquid biopsy platform. This device is said to use "a selection-free methodology capable of identifying all types of CTCs," including unexpected and new tumor cell subtypes. The researchers further examined another 740 or so CTCs with single-cell genome sequencing in an effort to determine the total global gene copy number variations. These data were analyzed and used to generate a "heterogeneity score" for the subpopulations of CTCs observed in each patient, but the analysis also entailed grouping CTCs into "mathematically similar subtypes." The analysis disclosed that a number of CTC subtypes predicted shorter overall survival and greater resistance to drug therapy even when those subtypes constituted a small percentage of overall CTC counts. These findings will be presented at the American Society for Clinical Oncology Genitourinary Cancers symposium this week, according to the statement.
Role reversal; Sprouty2 aids
spread in some CRCs
Sprouty2 is a gene known as offering tumor suppression in a wide range of cancers, but a recent press statement from the University of Missouri School of Medicine (Columbia, Mo.) suggested this gene offers a very different function for some colorectal cancers. The statement indicated that this is not seen as the case for all colorectal cancers, but the article explaining this development in Oncogene noted that two forms of Sprouty, Sprouty1 and Sprouty2, exhibited elevated messenger RNA transcription in some CRCs. While other markers played a significant role in the mechanisms by which Sprouty genes affect oncogenesis – including E-cadherin and one of the miR-194 genes – the authors concluded that the Sprouty2 gene seems to fuel epithelial-mesenchymal transitions in an as-yet unspecified subset of CRCs and thus "may serve as a biomarker of poor prognosis."
Poor enrollment dooms one
in five cancer studies
Device makers know all too well that clinical trial sites do not all enroll with similar degrees of success, but a successful enrollment effort is apparently a big problem with studies of cancer therapies that are sponsored by the National Cancer Institute. A recent story at the website for the Fred Hutchinson Cancer Center (Seattle) indicated that the need for a tissue sample still exe`rts the predictable effect on enrollment, but a distaste for randomization seems an impediment as well, a problem obviously not seen in phase II trials for demonstrating the safety of the therapeutic regime. The underlying analysis of nearly 780 cancer trials disclosed that enrollment hits phase III trials hardest, and fewer than one in every 20 cancer patients has evinced a willingness to participate in these studies. Another factor in enrollment seems to be income; a previous statement by the Hutchinson clinic made note of the fact that those whose income is less than $50,000 are much less willing to enroll in cancer studies.