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Chitale, D.

Publications and source records attributed to Chitale, D..

2 recordsLinked to original sources

Clonal evaluation of early onset prostate cancer by expression profiling of ERG, SPINK1, ETV1, and ETV4 on whole mount radical prostatectomy tissue

Expression profiles of ETS related genes and SPINK1 in early onset prostate cancer have not been thoroughly explored. We retrieved 151 radical prostatectomy specimens from young men with prostate cancer (<55yrs) and characterized the expression of ERG, SPINK1, ETV1 and ETV4 by dual immunohistochemistry and dual RNA in-situ hybridization. Age, race, family history, preoperative prostate-specific antigen, biochemical recurrence and pathological variables using whole mount radical prostatectomy tissue were collected. 313 tumor nodules from 151 men including 68 (45%) Caucasians and 61 (40%) African Americans. Positive family history of prostate cancer was observed in 65 (43%) patients. Preoperative prostate-specific antigen ranged from 0.3 to 52.7 ng/ml (mean 7.04). Follow-up period ranged from 1 to 123.7 months (Mean 30.3). Biochemical recurrence was encountered in 8/151 (5%). ERG overexpression was observed in 85/151 (56%) cases, followed by SPINK1 in 61/151 (40%), ETV1 in 9/149 (6%), and ETV4 in 4/141 (3%). There were 25/151 (17%) cases showing both ERG and SPINK1 overexpression within different regions of either the same tumor focus or different foci. Higher frequency of ERG overexpression was seen in younger patients ([&le;] 45 years old) (76% vs. 49%, p = 0.002213), Caucasian men (71% vs. 41% p = 0.000707), organ-confined tumors (64% vs. 33%, p = 0.00079), and tumors of Grade Groups 1 and 2 (62% vs. 26%, p = 0.008794). SPINK1 overexpression was more in African American men (68% vs. 26%, p = 0.00008), in tumors with high tumor volume (> 20%) and with anterior located tumors. ETV1 and ETV4 demonstrated rare overexpression in these tumors, particularly in the higher-grade tumors. This study expands the knowledge of the clonal evolution of multifocal cancer in young patients and support differences in relation to racial background and genetics of prostate cancer.

pathology

Detection of glioma and prognostic subtypes by non-invasive circulating cell-free DNA methylation markers

Genome-wide DNA methylation profiling has shown that epigenetic abnormalities are biologically important in glioma and can be used to classify these tumors into distinct prognostic groups. Thus far, DNA profiling has required surgically resected glioma tissue; however, gliomas release tumoral material into biofluids, such as blood and cerebrospinal fluid, providing an opportunity for a minimally invasive testing. While prior studies have shown that genetic and epigenetic markers can be detected in blood or cerebrospinal fluid (e.g., liquid biopsy [LB]), there has been low sensitivity for tumor-specific markers. We hypothesize that the low sensitivity is due to the targeted assay methods. Therefore, we profiled the genome-wide CpG methylation levels in DNA of tumor tissue and cell-free DNA in serum of glioma patients, to identify non-invasive epigenetic LB (eLB) markers in the serum that reflect the characteristics of the tumor tissue. From the epigenetic profiles of serum from patients diagnosed with glioma (N=15 IDH mutant and N=7 IDH wildtype) and with epilepsy (N=3), we defined glioma-specific and IDH-specific eLB signatures (Glioma-eLB and IDH-eLB, respectively). The epigenetic profiles of the matched tissue demonstrate that these eLB signatures reflected the signature of the tumor. Through cross-validation we show that Glioma-eLB can accurately predict a patients glioma from those with other neoplasias (N=6 Colon; N=14 Pituitary; N=3 Breast; N=4 Lung), non-neoplastic immunological conditions (N=22 sepsis; N=9 pancreatic islet transplantation), and from healthy individuals (sensitivity: 98%; specificity: 99%). Finally, IDH-eLB includes promoter methylated markers associated with genes known to be involved in glioma tumorigenesis (PVT1 and CXCR6). The application of the non-invasive eLB signature discovered in this study has the potential to complement the standard of care for patients harboring glioma.

cancer biology