Metachronous Advanced Neoplasia on Surveillance Colonoscopy in Patients With Young- vs Older-onset of Colorectal Cancer.

The incidence of colorectal cancer (CRC) and cancer-related mortality has increased in patients <55 years old.1 Consensus on optimal intervals for post-CRC surveillance colonoscopy in young patients is lacking. The primary endpoint of this study was comparison of rates of metachronous advanced neoplasia (AN) in patients diagnosed with CRC at <50 and 50-75 years. The secondary aim was to evaluate risk factors of metachronous AN.

Low Referral Rate for Genetic Testing in Racially and Ethnically Diverse Patients Despite Universal Colorectal Cancer Screening.

BACKGROUND & AIMS: Guidelines recommend that all colorectal tumors be assessed for mismatch repair deficiency, which could increase identification of patients with Lynch syndrome. This is of particular importance for minority populations, in whom hereditary syndromes are under diagnosed. We compared rates and outcomes of testing all tumor samples (universal testing) collected from a racially and ethnically diverse population for features of Lynch syndrome. METHODS: We performed a retrospective analysis of colorectal tumors tested from 2012 through 2016 at 4 academic centers. Tumor samples were collected from 767 patients with colorectal cancer (52% non-Hispanic white [NHW], 26% African American, and 17% Hispanic patients). We assessed rates of tumor testing, recommendations for genetic evaluation, rates of attending a genetic evaluation, and performance of germline testing overall and by race/ethnicity. We performed univariate and multivariate regression analyses. RESULTS: Overall, 92% of colorectal tumors were analyzed for mismatch repair deficiency without significant differences among races/ethnicities. However, minority patients were significantly less likely to be referred for genetic evaluation (21.2% for NHW patients vs 16.9% for African American patients and 10.9% for Hispanic patients; P = .02). Rates of genetic testing were also lower among minority patients (10.7% for NHW patients vs 6.0% for AA patients and 3.1% for Hispanic patients; P < .01). On multivariate analysis, African American race, older age, and medical center were independently associated with lack of referral for genetic evaluation and genetic testing. CONCLUSION: In a retrospective analysis, we found that despite similar rates of colorectal tumor analysis, minority patients are less likely to be recommended for genetic evaluation or to undergo germline testing for Lynch syndrome. Improvements in institutional practices in follow up after tumor testing could reduce barriers to diagnosis of Lynch diagnosis in minorities.

DNA damage repair deficiency as a predictive biomarker for FOLFIRINOX efficacy in metastatic pancreatic cancer.

Patients with pathogenic germline and somatic variants in DNA damage repair (DDR) genes may derive greater benefit with platinum-based chemotherapy in metastatic pancreatic ductal adenocarcinoma (PDAC). This study investigates the role of DDR genes as a predictive biomarker for response to first-line platinum chemotherapy with FOLFIRINOX in metastatic PDAC patients. Demographic, clinical, and pathologic variables were collected for patients with metastatic PDAC who received FOLFIRINOX as frontline treatment and who had germline and somatic genetic testing. Kaplan-Meier analysis of overall survival (OS) and progression free survival (PFS) were correlated to the presence of DDR pathogenic variants. Forty patients with metastatic PDAC met inclusion criteria. Germline genetic testing revealed germline pathogenic variants in DDR genes in 5 patients (12%), and somatic pathogenic variants in DDR genes in 4 patients (10%). Median PFS was significantly longer in patients with any (germline or somatic) pathogenic variant in DDR genes than in those without alterations 18.5 vs. 6.9 months (log-rank P=0.003). When restricted to the presence or absence of germline pathogenic variants in DDR genes, the median PFS was 18.5 vs. 7.4 months (log-rank P=0.005). The median OS for the entire cohort was 11.5 months was not statistically different between the two groups, however there were no deaths in the subgroup with germline pathogenic variants in DDR genes treated with frontline FOLFIRINOX. A subset of patients with metastatic PDAC and germline or somatic pathogenic variants in DDR genes have a statistically superior PFS when treated with the platinum containing regimen FOLFIRINOX. The role of DDR gene alterations as a predictive biomarker for FOLFIRINOX benefit should be further evaluated in prospective trials.

Restoration of desmosomal junction protein expression and inhibition of H3K9-specific histone demethylase activity by cytostatic proline-rich polypeptide-1 leads to suppression of tumorigenic potential in human chondrosarcoma cells.

Disruption of cell-cell junctions and the concomitant loss of polarity, downregulation of tumor-suppressive adherens junctions and desmosomes represent hallmark phenotypes for several different cancer cells. Moreover, a variety of evidence supports the argument that these two common phenotypes of cancer cells directly contribute to tumorigenesis. In this study, we aimed to determine the status of intercellular junction proteins expression in JJ012 human malignant chondrosarcoma cells and investigate the effect of the antitumorigenic cytokine, proline-rich polypeptide-1 (PRP-1) on their expression. The cell junction pathway array data indicated downregulation of desmosomal proteins, such as desmoglein (1,428-fold), desmoplakin (620-fold) and plakoglobin (442-fold). The tight junction proteins claudin 11 and E-cadherin were also downregulated (399- and 52-fold, respectively). Among the upregulated proteins were the characteristic for tumors gap junction ß-5 protein (connexin 31.1) and the pro-inflammatory pathway protein intercellular adhesion molecule (upregulated 129- and 43-fold, respectively). We demonstrated that PRP-1 restored the expression of the abovementioned downregulated in chondrosarcoma desmosomal proteins. PRP-1 inhibited H3K9-specific histone demethylase activity in chondrosarcoma cells in a dose-dependent manner (0.5 µg/ml PRP, 63%; 1 µg/ml PRP, 74%; and 10 µg/ml PRP, 91% inhibition). Members of the H3K9 family were shown to transcriptionally repress tumor suppressor genes and contribute to cancer progression. Our experimental data indicated that PRP-1 restores tumor suppressor desmosomal protein expression in JJ012 human chondrosarcoma cells and inhibits H3K9 demethylase activity, contributing to the suppression of tumorigenic potential in chondrosarcoma cells.