A simple, easy, and safe procedure aiming to improve liver regeneration could be of great clinical benefit in critical situations such as major hepatectomy, trauma, or hemorrhage. Low-power laser irradiation (LPLI) has come into a wide range of use in clinical practice by inducing regeneration in healthy and injured tissues. However, the effect of LPLI on the process of liver regeneration, especially those related to the molecular mechanisms, is not fully understood. Thus, the aim of the present study was to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized rats exposed to LPLI. We used Wistar male rats, which had their remaining liver irradiated or not with LPLI (wavelength of 632.8 nm and fluence of 65 mW/cm(2)) for 15 min after a 70% hepatectomy. We subsequently investigated hepatocyte growth factor (HGF), Met, Akt, and Erk 1/2 signaling pathways through protein expression and phosphorylation analyses along with cell proliferation (proliferating cell nuclear antigen (PCNA) and Ki-67) using immunoblotting and histological studies. Our results show that LPLI can improve liver regeneration as shown by increased HGF protein expression and the phosphorylation levels of Met, Akt, and Erk 1/2 accompanied by higher levels of the PCNA and Ki-67 protein in the remnant livers. In summary, our results suggest that LPLI may play a clinical role as a simple, fast, and easy-to-perform strategy in order to enhance the liver regenerative capacity of a small liver remnant after hepatectomy.

Analysis of blood and lymphatic vessel in colorectal cancer is controversial in the literature, possibly due to variations in the methods of analysis. In this study, it was aimed to search for a reliable approach in the quantification of angio- and lymphangiovascular density and area as a prognostic factor and to compare such vessel counts in normal mucosa, adenomas and cancer. A retrospective study was performed on 60 sporadic colorectal cancer, 30 colorectal adenomas, and 10 colorectal non-neoplastic lesions. Archival tissues were submitted to immunohistochemical evaluation using antibodies to CD31, CD34, CD105, VEGF-A, VEGF-C, and D2-40. Microvessel density and total vascular area were determined by computer image analysis and values were compared in the three groups of lesions; the prognostic value of these parameters was evaluated in the group of colorectal cancer. Most markers showed progressive vessel counts from non-neoplastic tissue to carcinoma, both for microvessel density and total vascular area. Only microvessel density determined by CD34 in the central areas of the cancer correlated with recurrence/metastasis (p = 0.04) and survival (p = 0.02). Different methods of quantification (microvessel counting versus estimation of total vascular area), immunohistochemical markers (pan-endothelial marker versus neovessels and lymphatic markers), and areas of analysis (periphery versus inner portions of the lesion) were assessed using image analysis. The results corroborate the increase in vascularization of carcinoma and suggest that microvessel density determined by immunostaining for CD34 in the inner portion of the tumor might represent a prognostically relevant parameter in colorectal cancer.

The sub-nipple tissue (SNT) examination has been used by surgeons to preserve, or not, the nipple in nipple-sparing mastectomy. However, it is uncertain whether SNT evaluation can predict nipple involvement. The aim of this study was to evaluate the accuracy, sensitivity, specificity, PPV, and NPV of the intraoperative frozen section and imprint cytology, and permanent histology of SNT to predict the involvement of the nipple in breast carcinoma and to compare the three exams. A prospective study was performed with 68 consecutive breast carcinoma women who had undergone mastectomy or central segmentectomy (removing nipple-areolar complex). After surgery, the nipple-areolar complex was dissected simulating a nipple-sparing flap (ex vivo). The SNT was subsequently removed and submitted to frozen section, imprint cytology, and permanent histology. The nipple was examined separately by paraffin histopathology and was considered the gold standard. The occult nipple involvement rate was 11.7 %. The frozen section, cytology, and permanent histology of SNT presented accuracy 86.8, 76.5, and 86.8 %; sensitivity 50, 37.5, and 62.5 %; specificity 91.7, 81.7, and 90 %; PPV 44.4, 21.4, and 45.5 %; and NPV 93.2, 90.7, and 94.7 %, respectively. The accuracy of the frozen section was similar to that of permanent histology (p = 0.77) and both were better than cytology (p = 0.01). False negative rates were 6.8 % for frozen section, 9.3 % for cytology and 5.3 % for paraffin. SNT evaluation is a good method for predicting occult nipple involvement; the outcomes showed a good accuracy and low false negative rate for the frozen section, cytology, and permanent histology exams. When we compared the exams, the frozen section was similar to permanent histology and more accurate than imprint cytology.

The liver regeneration is an important clinical issue after major hepatectomies. Unfortunately, many organs (including the liver) exhibit age-related impairments regarding their regenerative capacity. Recent studies found that low-power laser irradiation (LPLI) has a stimulatory effect on the liver regeneration process. However, its effects in elderly remain unknown. Thus, this study aimed to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized elderly rats exposed to LPLI. The effects of 15 min of LPLI (wavelength of 632.8 nm; fluence of 0.97 J/cm(2); total energy delivered of 3.6 J) were evaluated in hepatectomized elderly Wistar male rats. Afterwards, through immunoblotting approaches, the protein expression and phosphorylation levels of hepatocyte growth factor (HGF), Met, Akt and Erk 1/2 signaling pathways as well as the proliferating cell nuclear antigen (PCNA) were investigated. It was observed that LPLI was not able to improve liver regeneration in elderly rats as evidenced by the lack of improvement of HGF and PCNA protein expression or phosphorylation levels of Met, Akt and Erk 1/2 in the remnant livers. In sum, this study demonstrated that the main molecular pathway, i.e. HGF/Met → Akt and Erk 1/2 → PCNA, involved in the hepatic regeneration process was not improved by LPLI in elderly hepatectomized rats, which in turn rules out LPLI as an adjuvant therapy, as observed in this protocol of liver regeneration evaluation (i.e. at 48 h after 70 % resection), in elderly.

Background Laboratory reports on adipose tissue suggest that fat grafting to the breast may pose an oncologic risk. One possible reason for this is the theoretic chronic inflammation due to adipokynes released by grafted white adipose tissue (WAT). Objectives The aim of this study was to analyze inflammatory activity in lipofilled breast through the use of proinflammatory markers. Methods Fifty-four paired-breasts of female rats were divided into 4 groups: control, sham, and breasts grafted with either autologous subcutaneous (SC) WAT or autologous omentum (OM). The WAT was prepared through centrifugation, and the grafting was performed with the use of 0.9-mm blunt-tip cannula. The rats were killed 8 weeks postoperatively, and their breasts were harvested for immunohistochemical staining for CD68-expressing macrophages, gene expression (real-time PCR) for monocyte chemoattractant protein 1 (MCP-1), F4/80, Cox-2, and IL-6. Results The weights of the rats that underwent a procedure differed from those of the unmanipulated control group (P < 0.01). The macrophage counts of CD68 differed only between breasts lipofilled with OM and control (P < 0.01). MCP-1, F4/80, and Cox-2 were similarly expressed among the groups (P = 0.422, P = 0.143, and P = 0.209, respectively). The expression of IL-6 differed between breast samples grafted with SC and OM WAT (P = 0.015), but not between samples of control and OM (P = 0.752), and control and SC (P = 0.056). Conclusions No inflammation activity was identified in the microenvironment of lipofilled breasts, indicating that chronic inflammation does not seem to be triggered by the breast lipofilling procedure.

Blood and lymphatic vessel proliferation is essential for tumor growth and progression. Most colorectal carcinomas develop from adenomas (adenoma-carcinoma sequence) in a process due to accumulation of molecular genetic alterations. About 5% of adenomatous polyps are expected to become malignant, but data on the differential angiogenic patterns of these lesions in patients with and without concomitant cancer are missing. The aim of the present study is to compare the angiogenic and lymphatic patterns of adenomatous polyps from patients with and without sporadic cancer. Thirty adenomatous polyps (15 from patients with another principal malignant lesion, and 15 from patients without cancer) were submitted to immunohistochemical staining for CD105 (marker for neoangiogenesis) and D2-40 (marker for lymphatic endothelium). Microvessel density and total vascular area were determined by computer image analysis to quantify the immunostained and total areas, and to assess the number of microvessels. Adenomas from patients with carcinoma showed significantly higher values of total vascular area determined by immunostaining for CD105 (cutoff value = 4386 μm 2 ; P = 0.019) and of lymphatic microvessel density determined by immunostaining with D2-40 (cutoff value = 11.5; P = 0.041) when compared with those from patients without cancer. The present data indicate a significant increase in blood microvascular area and in lymphatic microvascular counts in adenomas removed from patients with cancer.

No theoretical risk of cancer was detected in the microenvironment of the lipofilled rat breast.

BackgroundAlthough its unclear oncological risk, which led to more than 20 years of prohibition of its use, fat grafting to the breast is widely used nowadays even for aesthetic purposes. Thus, we proposed an experimental model in rats to analyze the inflammatory activity, cellular proliferation and levels of Plasminogen Activator Inhibitor (PAI-1) in grafted fat, and in native fat exposed to high-energy diet in order to study the oncological potential of fat tissue.MethodsSamples of grafted fat of rats on regular-energy diet were compared with paired samples of native fat from the same rat on regular-energy diet and on high-energy diet in a different time. Analysis involved microscopic comparisons using hematoxylin-eosin staining, immunohistochemistry with anti-CD68-labelled macrophages, and gene expression of Ki-67 and PAI-1.ResultsHematoxylin-eosin staining analyses did not find any atypical cellular infiltration or unusual tissue types in the samples of grafted fat. The inflammatory status, assessed through immunohistochemical identification of CD68-labelled macrophages, was similar among samples of native fat and grafted fat of rat on regular-energy diet and of native fat of rats on high-energy diet. Real-time PCR revealed that high-energy diet, but not fat grafting, leads to proliferative status on adipose tissue (overexpression of ki-67, p = 0.046) and raised its PAI-1 levels, p < 0.001.ConclusionWhile the native adipose tissue overexpressed PAI-1 and KI67 when exposed to high-energy diet, the grafted fat by itself was unable to induce cellular proliferation, chronic inflammatory activity and/or elevation of PAI-1 levels.