Pathologic Features of Hereditary Non-Polyposis Colorectal Cancer

In hereditary non-polyposis colorectal cancer (HNPCC) patients, the cancer frequently arises in the proximal colon and is often multiple (synchronous or metachronous). Pathologic differences seem to exist between hereditary and sporadic large bowel cancer, but the data are not uniform. Many authors reported that the following histologic features are often present in HNPCC: 1) mucinous histotype, 2) poorly differentiated tumors, 3) presence of peritumoral lymphocytic infiltrate, with Crohn's-like lymphoid reaction. Such features have also been found in apparently sporadic colorectal cancer with, but not in sporadic colorectal cancer without DNA replication errors. Many studies have suggested that adenoma plays a main role in HNPCC carcinogenesis, and that the “adenoma-carcinoma sequence” may be the pathway to cancer in HNPCC as in sporadic colorectal cancer. Moreover, HNPCC adenomas show an early onset, villous component, high-grade dysplasia, and positivity for DNA replication errors more frequently than sporadic adenomas. Such data suggest that the adenoma-carcinoma sequence is accelerated in HNPCC and that surveillance in these patients should therefore be strict to avoid cancer development.

Hydrogen peroxide-triggered gene silencing in mammalian cells through boronated antisense oligonucleotides

Hydrogen peroxide (H2O2) is a reactive oxygen species (ROS) involved in various diseases, including neurodegeneration, diabetes, and cancer. Here, we introduce a new approach to use H2O2 to modulate specific gene expression in mammalian cells. H2O2-responsive nucleoside analogues, in which the Watson-Crick faces of the nucleobases are caged by arylboronate moieties, were synthesized. One of these analogues, boronated thymidine (dTB ), was incorporated into oligodeoxynucleotides (ODNs) using an automated DNA synthesizer. The hybridization ability of this boronated ODN to complementary RNA was clearly switched in the off-to-on direction upon H2O2 addition. Furthermore, we demonstrated H2O2-triggered gene silencing in mammalian cells using antisense oligonucleotides (ASOs) modified with dTB . Our approach can be used for the regulation of any gene of interest by the sequence design of boronated ASOs and will contribute to the development of targeted disease therapeutics.

Effect of comorbidities on long-term outcomes after thoracoscopic surgery for stage I non-small cell lung cancer patients with chronic obstructive pulmonary disease

Background

We assessed how the severity of chronic obstructive pulmonary disease (COPD) and other comorbidities affect long-term survival after thoracoscopic lung resection for c-stage I non-small cell lung cancer (NSCLC).

Methods

Patients with c-stage I NSCLC who underwent thoracoscopic lung resection at our hospital between 2006 to 2014 were retrospectively analyzed. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) spirometric grades were used to classify the severity of COPD, and comorbidity was classified according to the Charlson comorbidity index (CCI). Various outcomes were assessed and compared.

Results

The cohort comprised 404 patients with NSCLC, of whom 133 were diagnosed with COPD (51 as GOLD 1, 79 as GOLD 2, and 3 as GOLD 3) and 271 were diagnosed without COPD. The 5-year overall survival (OS) rates were 86.0%, 80.2%, and 71.1% for the non-COPD, GOLD 1, and GOLD 2/3 groups, respectively (P=0.0221); the corresponding 5-year disease-specific survival (DSS) rates were 91.7%, 86.9%, and 85.1% (P=0.2136). Univariate analysis indicated that sex, smoking status, pathology, COPD severity, CCI, and pathological stage were associated with OS, and multivariate analysis confirmed the association with CCI and pathological stage. Postoperative complications were significantly more frequent in the GOLD 1 (21.5%) and GOLD 2/3 (26.8%) groups than in the non-COPD group (12.1%) (P=0.0040).

Conclusions

Following thoracoscopic surgery (TS) for NSCLC, patients with COPD had a poorer OS than patients without COPD. However, the CCI and not the COPD severity was the independent prognostic factor for OS. Comorbidities adversely affected long-term survival of patients with stage I NSCLC and COPD after TS, and the same effect can be oncologically expected regardless of the COPD severity.

Soluble Vascular Adhesion Protein-1 Mediates Spermine Oxidation as Semicarbazide-Sensitive Amine Oxidase: Possible Role in Proliferative Diabetic Retinopathy

Purpose/Aim of the study: To explore the possible role of vascular adhesion protein-1 (VAP-1) via its enzymatic function as a semicarbazide-sensitive amine oxidase (SSAO) in the pathogenesis of proliferative diabetic retinopathy (PDR).

MATERIALS AND METHODS

The levels of soluble VAP-1/SSAO and the unsaturated aldehyde acrolein (ACR)-conjugated protein, N^ε-(3-formyl-3, 4-dehydropiperidino) lysine adduct (FDP-Lys), were measured in vitreous fluid samples of PDR and non-diabetic patients using ELISA. Recombinant human VAP-1/SSAO (rhVAP-1/SSAO) was incubated with spermine, with or without semicarbazide or RTU-1096 (a specific inhibitor for VAP-1/SSAO). Immunofluorescence assays were performed to assess the localization of VAP-1/SSAO and FDP-Lys in fibrovascular tissues from patients with PDR. The impact of ACR on cultured retinal capillary endothelial cells was assessed using a cell viability assay and total glutathione (GSH) measurements.

RESULTS

The levels of sVAP-1/SSAO and FDP-Lys were elevated in the vitreous fluid of patients with PDR. Incubation of rhVAP-1 with spermine resulted in the generation of hydrogen peroxide and FDP-Lys and the production was inhibited by semicarbazide and RTU-1096. In fibrovascular tissues, FDP-Lys and VAP-1/SSAO were present in endothelial cells. ACR stimulation reduced GSH levels in the cultured endothelial cells in a dose-dependent manner and caused cellular toxicity.

CONCLUSIONS

Our results indicate the pathological role of sVAP-1/SSAO to generate hydrogen peroxide and toxic aldehyde ACR, both of which are associated with oxidative stress, as a consequence of spermine oxidation in eyes with PDR.

Thoracoscopic thymectomy is a feasible and less invasive alternative for the surgical treatment of large thymomas

OBJECTIVES

Thoracoscopic surgery is widely used for the surgical treatment of thymoma. However, large-sized thymomas are typically treated using open surgery. This study evaluated the feasibility of performing thoracoscopic thymectomy (TT) for thymoma ≥50 mm.

METHODS

A retrospective review was conducted on 135 patients who underwent TT or open thymectomy (OT) for Masaoka stage I-IVa thymoma between 1996 and 2014.

RESULTS

Patients were first divided into two groups based on thymoma size: thymoma ≥50 mm and thymoma <50 mm groups. There was no significant difference in the 5-year disease-free survival (DFS) between the groups ( P  = 0.5352). Patients in the thymoma ≥50 mm group were further subdivided into TT and OT groups. The length of postoperative hospital stay was significantly shorter in the TT group than in the OT group (5 vs 14 days, P  < 0.0001), with significantly fewer postoperative complications (6 patients vs 14 patients, P  = 0.0008). There was no significant difference in the 5-year DFS between patients with thymoma ≥50 mm in the TT and OT groups ( P  = 0.3501). Finally, patients undergoing TT were further subdivided into thymoma ≥50 mm and thymoma <50 mm groups and, no significant difference in the 5-year DFS was found between these groups ( P  = 0.6661). Masaoka stages III-IV, but not thymoma size, were an independent prognostic factor for DFS.

CONCLUSIONS

These results demonstrate the decreased invasiveness and feasibility of TT for large-sized thymomas.

Surgical and oncological outcomes of thoracoscopic thymectomy for thymoma

Thymoma remains the most common primary anterior mediastinal neoplasm. Surgical resection remains central to the treatment of thymoma, with thoracoscopic thymectomy (TT) being increasingly performed. This present review article aimed to summarize current studies comparing TT and open thymectomy (OT). Recently, most patients with Masaoka stage I-II thymoma have been receiving TT. This procedure is associated with a significantly shorter post-operative hospital stay, decreased intraoperative blood loss, and fewer complications compared with OT. Recurrence rates of thymoma after TT range from 0% to 6.7%, and the 5-year disease-free survival (DFS) ranges from 83.3% to 96%. The oncological outcomes of TT are comparable to that of OT. Masaoka stage and the World Health Organization (WHO) type classification are valuable predictors of the prognosis of thymoma; hence, the optimal treatment for thymoma should be performed according to these two. TT is less invasive, with equivalent oncological outcomes, when compared with the OT. Minimally invasive surgery including TT for stage I-II thymomas is becoming the mainstay of therapy.