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Kaposi sarcoma (KS), a common HIV-associated malignancy, presents a range of clinicopathological features. Kaposi sarcoma-associated herpesvirus (KSHV) is its etiologic agent, but the contribution of viral genomic variation to KS development is poorly understood. To identify potentially influential viral polymorphisms, we characterized KSHV genetic variation in 67 tumors from 1–4 distinct sites from 29 adults with advanced KS in Kampala, Uganda. Whole KSHV genomes were sequenced from 20 tumors with the highest viral load, whereas only polymorphic genes were screened by PCR and sequenced from 47 other tumors. Nine individuals harbored ≥1 tumors with a median 6-fold over-coverage of a region centering on K5 and K6 genes. K8.1 gene was inactivated in 8 individuals, while 5 had mutations in the miR-K10 microRNA coding sequence. Recurring inter-host polymorphisms were detected in K4.2 and K11.2. The K5-K6 region rearrangement breakpoints and K8.1 mutations were all unique, indicating that they arise frequently de novo. Rearrangement breakpoints were associated with potential G-quadruplex and Z-DNA forming sequences. Exploratory evaluations of viral mutations with clinical and tumor traits were conducted by logistic regression without multiple test corrections. K5-K6 over-coverage and K8.1 inactivation were tentatively correlated (p<0.001 and p = 0.005, respectively) with nodular rather than macular tumors, and with individuals that had lesions in ≤4 anatomic areas (both p≤0.01). Additionally, a trend was noted for miR-K10 point mutations and lower survival rates (HR = 4.11, p = 0.053). Two instances were found of distinct tumors within an individual sharing the same viral mutation, suggesting metastases or transmission of the aberrant viruses within the host. To summarize, KSHV genomes in tumors frequently have over-representation of the K5-K6 region, as well as K8.1 and miR-K10 mutations, and each might be associated with clinical phenotypes. Studying their possible effects may be useful for understanding KS tumorigenesis and disease progression. Author summary: How chronic KSHV infection leads to the development of KS is poorly understood, however, evaluation of KSHV mutations found in vivo may assist this understanding. Here, targeted and whole genome sequencing of KSHV in multiple tumors from individuals in Uganda revealed an increase in copy number of the region of the genome encompassing the K5 and K6 genes or inactivation of the K8.1 gene in at least a third of the individuals. In an exploratory analysis these mutations were found more in tumors of nodular than macular morphotype and in individuals with fewer lesions. These mutations were unique across individuals, indicating that they arise frequently de novo. Point mutations in the miR-K10 micro-RNA sequence were weakly associated with lower survival. Occasionally, distinct tumors within an individual shared the same viral mutation, suggesting metastases or transmission of the aberrant viruses within the host. Clustering of genome rearrangement breakpoints were associated with potential G-quadruplex and Z-DNA forming regions in the viral DNA. The viral genetic differences uncovered and their associated clinical phenotypes call for targeted surveys of these genes to potentially establish a prognostic or treatment-selective biomarker and more studies into their roles in tumorigenesis. [ABSTRACT FROM AUTHOR]

Background and Aim: Because most colorectal cancer patients survive beyond five years, understanding quality of life among these long-term survivors is essential to providing comprehensive survivor care. We sought to identify personal characteristics associated with reported quality of life in colorectal cancer survivors, and sub-groups of survivors potentially vulnerable to very low quality of life. Methods: We assessed quality of life using the Veterans RAND 12-item Health Survey within a population-based sample of 1,021 colorectal cancer survivors in the Seattle Colorectal Cancer Family Registry, approximately 5 years post-diagnosis. In this case-only study, mean physical component summary scores and mental component summary scores were examined with linear regression. To identify survivors with substantially reduced ability to complete daily tasks, logistic regression was used to estimate odds ratios for “very low” summary scores, defined as a score in the lowest decile of the reference US population. All cases were followed for vital status following QoL assessment, and mortality was analyzed with Cox proportional hazards regression. Results: Lower mean physical component summary score was associated with older age, female sex, obesity, smoking, and diabetes or other co-morbidity; lower mean mental component summary score was associated with younger age and female sex. Higher odds of very low physical component summary score was associated with older age, obesity, less education, smoking, co-morbidities, and later stage at diagnosis; smoking was associated with higher odds of very low mental component summary score. A very low physical component score was associated with higher risk of mortality (hazard ratio (95% confidence interval): 3.97 (2.95–5.34)). Conclusions: Our results suggest that identifiable sub-groups of survivors are vulnerable to very low physical components of quality of life, decrements that may represent meaningful impairment in completing everyday tasks and are associated with higher risk of death. [ABSTRACT FROM AUTHOR]

Background: MicroRNAs (miRNAs) are regulatory RNAs, stable in circulation, and implicated in colorectal cancer (CRC) etiology and progression. Therefore they are promising as early detection biomarkers of colorectal neoplasia. However, many circulating miRNAs are highly expressed in blood cells, and therefore may not be specific to colorectal neoplasia. Methods: We selected 7 miRNA candidates with previously reported elevated expression in adenoma tissue but low expression in blood cells (“rare” miRNAs), 2 previously proposed as adenoma biomarkers, and 3 implicated in CRC. We conducted a colonoscopy-based case-control study including 48 polyp-free controls, 43 advanced adenomas, 73 non-advanced adenomas, and 8 CRC cases. miRNAs from plasma were quantified by qRT-PCR. Correlations between miRNA expression levels, adjusted for age and sex, were assessed. We used polytomous logistic regression to estimate odds ratios (ORs) and 95% confidence intervals quantifying the association between expression levels of miRNAs and case groups. We also conducted nonparametric receiver operating characteristic (ROC) analyses and estimated area under the curve (AUC). Results: miRNAs with high expression levels were statistically significantly correlated with one another. No miRNAs were significantly associated with non-advanced or advanced adenomas. Strong (ORs >5) and significant associations with CRC were observed for 6 miRNA candidates, with corresponding AUCs significantly >0.5. Conclusions: These candidate miRNAs, assayed by qRT-PCR, are probably unsuitable as blood-based adenoma biomarkers. Strong associations between miRNAs and CRC were observed, but primarily with miRNAs highly expressed in blood cells. These results suggest that rare miRNAs will require new detection methods to serve as circulating biomarkers of adenomas. [ABSTRACT FROM AUTHOR]