Low Osteopontin N-Terminal Fragment and Carotid Plaque Stability Associated with Statin or Antiplatelet Therapy.

INTRODUCTION: Full-length osteopontin (OPN-FL), whose levels are elevated in association with atherosclerosis, is cleaved by thrombin, resulting in the formation of a putatively biologically-active N-terminal cleavage product (OPNN). This study addresses the hypothesis that statin and antiplatelet therapy in hypertensive patients specifically reduces OPN-N, rather than OPN-FL, in carotid plaques. METHODS: Seventy-four carotid plaques were collected from patients who underwent carotid endarterectomy (CEA). Plaque tissue was used to measure OPN proteins and for histological and immunohistochemical characterization. RESULTS: There were 22 statin-negative and 52 statin-treated patients. In the carotid plaque, immunohistochemical staining for macrophages was higher in statin-negative vs. statin-treated patients (high CD68 immunostaining was in 61.9 vs. 28.6%, p=.03, respectively). OPN-FL staining had a similar trend, but without statistical significance (78.7 vs. 47.8%, p=.08, respectively). Western blot analysis of plaque OPN-FL showed that statin treatment was not associated with significant alteration of its abundance, but with a significantly lower plaque content of OPN-N [median 0.08 (IQR 0.05-1.01) vs. 0.81 (IQR 0.27-2.86), respectively, p=.015]. Comparable pattern of association between OPN proteins and antiplatelet therapy was found: the abundance of OPN-FL was not different in plaques from untreated or treated patients, while the abundance of OPN-N was significantly reduced in antiplatelet treated vs. non-treated patients [0.08, (IQR 0.05-0.66) vs. 0.89, (IQR 0.13-1.94), p=0.004]. CONCLUSION: The effect of anti-atherosclerotic treatment on carotid plaques of hypertensive patients more readily associates with OPN-N than with OPN-FL expression, suggesting that anti-atherosclerotic treatment including statins and antiplatelet drugs modulates the "OPN system".

Cell-free DNA blood levels in colorectal cancer patients do not correlate with mismatch repair-proficiency.

UNLABELLED: While sporadic cases of colorectal cancer (CRC) most commonly arise via the well-characterized chromosomal instability pathway (CIN), most other cases develop via a serrated neoplasia pathway (CIMP), in which methylation of CpG islands results in silencing of DNA nucleotide mismatch repair (MMR)-related genes, and a high level of microsatellite instability (MSI). MSI-high tumors typically show proximal location, mucinous histology, poor differentiation, and lymphocytic infiltration. Cell-free circulating DNA (CFD) may become elevated in CRC patients compared to healthy individuals. Because of these biological differences, we hypothesized that compared to MMR-proficient tumors MMR-deficient CRCs may produce higher CFD blood levels. PATIENTS AND METHODS: Forty-one patients with newly-diagnosed CRC from all stages were studied for MMR-proficiency status, and CFD and carcinoembryonic antigen (CEA) blood levels. MMR proficiency was evaluated in formalin-fixed, paraffin-embedded tissues by immunohistochemistry (IHC) for MLH1/MSH2. CFD plasma levels were measured with SYBR gold nucleic acid gel staining on fluorometry. MMR-proficiency status was studied by clinicopathological parameters, CFD and CEA blood levels. RESULTS: Tumors were MMR-proficient, and -deficient in 16 patients (39%), and 25 patients (61%), respectively. The mean age of MMR-deficient patients was approximately 10 years higher than that of MMR-proficient patients (61.2±8.4 years versus 71.9±9.7 years, p=0.07). MMR-deficient tumors were more often proximally-located, (p=0.018). The mean CFD plasma levels in MMR-proficient, and MMR-deficient patients were 795±431 ng/ml, and 906±494 ng/ml, respectively (p=0.68). The mean CEA serum levels in MMR-proficient and MMR-deficient patients were 10.4±17.6 µg/l, and 15±48 µg/l, respectively (p=0.46). CONCLUSION: Compared to MMR-proficient CRCs, MMR-deficient tumors occurred in older patients, and were more commonly proximally-located. Despite the presence of distinct biological and histopathological characteristics, both tumor types produced similar CFD blood levels.

N-terminal rather than full-length osteopontin or its C-terminal fragment is associated with carotid-plaque inflammation in hypertensive patients.

BACKGROUND: Hypertensive patients develop carotid atherosclerotic plaques with enhanced inflammation. Full-length osteopontin (OPN-FL), a multifunctional protein whose levels are elevated in association with atherosclerosis, is cleaved by thrombin and matrix metalloproteinases to form a C-terminal and a putatively biologically active N-terminal fragment (OPN-C, OPN-N, respectively). We conducted a study to examine whether plaque inflammation in hypertensive patients corresponds to the expression of OPN or of its cleaved forms or both. METHODS: We collected 42 carotid plaques from 41 consecutive hypertensive patients during carotid endarterectomy. Plaque tissue was used to measure matrix metalloproteinase-12 (MMP-12) and OPN proteins, and for the classification of plaques as showing low- or high-degree inflammation through histological and immunohistochemical evaluation. RESULTS: Fifteen highly inflamed plaques and 27 plaques with characteristics of low-grade inflammation were collected. Moderate to heavy staining for OPN characterized 87% of the plaques with high-degree inflammation but only 44% of those with low-degree inflammation, corresponding to the percentages of plaques that were heavily stained for the macrophage marker CD68 (93% versus 26%, respectively, P < 0.01). Western blot analysis showed that the abundance of OPN-FL and OPN-C was comparable in the two groups. However, the abundance of OPN-N was significantly greater in the highly inflamed plaques (median, 3.8 (range, 0.8-7.3) vs. median, 0.9 (range, 0.2-1.5); P = 0.017, respectively). The abundance of MMP-12 was significantly greater in the high- than in the low-degree plaque inflammation group (4.8 (range 1.9-8.8) vs. 1.1 (range 0.3-1.4), respectively; P = 0.03). CONCLUSIONS: The N-terminal fragment of osteopontin, rather than OPN-FL or OPN-C, is associated with carotid plaque inflammation in hypertensive patients. Future studies should assess whether targeting OPN cleavage could present a new approach to preventing high-risk carotid plaques.

Serous papillary adenocarcinoma of the rete testis: unusual ultrasonography and pathological findings.

We report a case of serous papillary adenocarcinoma of the rete testis in a 22-year-old man. Adenocarcinoma of the rete testis is highly resistant to radiotherapy and any known chemotherapeutic regimen. We recommend radical orchiectomy At last follow up, the patient was well, without any evidence of recurrence, ten years after surgery.