Ki-67 Immunoreactivity Research Articles

EXPRESSION OF MCM3 AND KI-67 AS DIAGNOSTIC MARKERS IN BENIGN AND MALIGNANT SALIVARY GLAND TUMORS

Introduction: Salivary gland tumors (SGTs) may represent a considerable diagnostic challenge, primarily because of the complexity of theclassification and the rarity of several entities. Since proliferative activity is a reliable method to assess tumor biology. There has been continuousresearch to find such biological markers. Ki-67 is a widely accepted proliferation marker, with its expression tightly associated with the cell cycle. Itis implicated in many of human cancers as a prognostic factor. MCM-3, member of minichromosome maintenance proteins family, is upregulatedin proliferating cells. MCM-3 overexpression in almost all human cancers implicates that it might facilitate the tumorigenesis byplaying a role in the malignant transformation of cells.Objectives: to evaluate the MCM-3 protein expression in benign and malignant salivary gland tumors and compare the obtained results with theexpression of Ki-67 proliferation antigen.Materials and methods: Immunohistochemical analysis of 20 cases of SGTs with 2 sections from each specimen (20 sections for antiKi-67antibody and 20 sections for antiMCM3antibody) and 5 control cases. Immunohistochemical staining was performed using a Labeled Strept-Avidin Biotin method (LSAB).Results: Normal salivary gland tissue showed negative immunoreactivity for both Ki-67 and MCM-3 in epithelial and myoepithelial cells. All theexamined cases showed positive expression for both proliferative markers in benign and malignant SGTs, with different intensities.Conclusions: The proliferative markers Ki-67 and MCM-3 proteins are overexpressed in malignant salivary gland tumors, than benign ones.Both Ki-67 and MCM-3 may be reliably applied as diagnostic markers to distinguish benign from malignant salivary gland tumors.

Immunohistochemical and genetic evaluations of epidermal growth factor receptor (EGFR) in oral squamous cell carcinoma

ObjectivesTo study the role of epidermal growth factor receptor (EGFR) in oral squamous cell carcinoma (OSCC), protein expression, gene amplification, and mutations were analyzed in OSCC as well as leukoplakia. Immunoreactivity of Ki-67 and K-Ras gene mutations were simultaneously evaluated. Material and methodsEighty-two OSCC and 10 leukoplakia specimens were immunohistochemically examined with antibodies against EGFR and Ki-67. Amplification of EGFR was evaluated by chromogenic in situ hybridization (CISH). In 14 OSCC samples, EGFR exons 19, 21 and K-Ras exon 2 were analyzed by direct DNA sequencing. ResultsImmunohistochemical reactivity for EGFR and Ki-67 was detected in epithelial cells of leukoplakia and in carcinoma cells of OSCC. EGFR and Ki-67 immunoreactivity was significantly higher in OSCC than in leukoplakia. Leukoplakia showed no EGFR amplification, whereas OSCC exhibited low-level amplification in 19 cases and high-level amplification in 3 cases, respectively. OSCC cases with EGFR amplification showed slightly higher EGFR and Ki-67 immunoreactivity than those without amplification. In OSCC, EGFR immunoreactivity significantly correlated with the mode of invasion, invasion depth, as well as EGFR amplification significantly correlated with the degree of differentiation, mode of invasion, recurrence, and postoperative metastasis. Direct DNA sequencing of EGFR and K-Ras did not show any gene alterations in OSCC. ConclusionEGFR aberrations might contribute to carcinogenesis, invasion, metastasis as well as poor outcomes in OSCC. EGFR-targeting therapy with anti-EGFR monoclonal antibody agents may be beneficial in OSCC patients.

Corticotropin-Releasing Hormone Receptor 2 Signaling Promotes Mucosal Repair Responses after Colitis

The corticotropin-releasing hormone family mediates functional responses in many organs, including the intestine. Activation of corticotropin-releasing hormone receptor 2 (CRHR2) in the colonic mucosa promotes inflammation during acute colitis but inhibits inflammation during chronic colitis. We hypothesized that specific modulation of CRHR2 signaling in the colonic mucosa can promote restoration of the epithelium through stimulation of cell proliferative, migratory, and wound healing responses. Mucosal repair was assessed after dextran sodium sulfate (DSS)-induced colitis in mice receiving intracolonic injections of a CRHR2 antagonist or vehicle and in Crhr2(-/-) mice. Histologic damage, cytokine expression, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, and Ki-67 immunoreactivity were evaluated. Cell viability, proliferation, and migration were compared between parental and CRHR2-overexpressing colonic epithelial cells. Protein lysates were processed for phosphoprotein assays and a wound healing assay performed invitro. Administration of a CRHR2 antagonist after DSS-induced colitis increased disease activity, delayed healing, and decreased epithelial cell proliferation invivo. Colons from these mice also showed increased apoptosis and proinflammatory cytokine expression. Compared with controls, Crhr2(-/-) mice showed increased mortality in the DSS healing protocol. CRHR2-overexpressing cells had increased proliferation and migration compared with parental cells. Wound healing and signal transducer and activator of transcription 3 activity were elevated in CRHR2-overexpressing cells after urocortin 2 and IL-6 treatment, suggesting advanced healing progression. Our results suggest that selective CRHR2 activation may provide a targeted approach to enhance mucosal repair pathways after colitis.

Abstract 17796: Toll-like Receptor 9 Signaling Pathway Ameliorates Cardiac Rupture After Myocardial Infarction by Promoting the Proliferation of Myofibroblasts

Background: Toll-like receptor (TLR) 9 signaling pathway plays an important role in inflammatory responses in failing hearts in response to pressure overload and in the pathogenesis of heart failure. However, the role of the signaling pathway in left ventricular (LV) remodeling after myocardial infarction, where necrotic cardiomyocyte death is prominent, has not been elucidated. Methods and Results: Wild-type (WT) (n=9) and TLR9 knockout (KO) mice (n=11) were subjected to the left coronary artery ligation to induce myocardial infarction (MI). The survival ratio 7 days after MI was significantly reduced in KO mice (36.4%) than in WT mice (88.9%) (p<0.05). All of dead mice in both groups exhibited cardiac rupture. The peak time occurring rupture was 4 days after MI. The ischemia area at risk, identified by a lack of Evans blue staining were not significantly different between the WT and KO hearts (29.7% and 28.9%). Cardiovascular MRI imaging perfomed at 3 days post MI showed no difference in infarct size, LV volume and ejection fraction between WT and KO mice. The mRNA expression levels of inflammatory cytokines including IL-6 and TNFα were not significantly different in KO mice compared with WT mice. Immunohistochemical analysis did not show the significant difference in the extent of neutrophilic infiltration (CD45 positive cells) and macrophage accumulation (CD68 positive cells) in the infarct region between WT and KO mice. The number of myofibroblasts (αsmooth muscle action-positive cells), one of the cellular components in the formation of granulation tissue, was significantly reduced in KO mice (346 cells /mm2) compared to WT mice (1547 cells /mm2) (p<0.05). The number of myofibroblasts exhibiting Ki-67 immunoreactivity was also markedly lower in KO mice (113 cells /mm2) than in WT mice (789 cells /mm2) (p<0.05), indicating that the proliferative activity of myofibroblasts was significantly decreased in the infarcted regions of KO hearts. Conclusions: TLR9 signaling pathway is not involved in inflammatory responses in the infarcted regions of MI hearts but ameliorates cardiac rupture after MI by promoting the proliferation of myofibroblasts.

Nicotine inhibits hippocampal and striatal acetylcholinesterase activities, and demonstrates dual action on adult neuronal proliferation and maturation

AimThe present study investigated the effects of nicotine on acetylcholinesterase (AChE) activities in the hippocampus and striatum; and on immunoreactivity of certain neurogenic markers in the dentate gyrus (DG) of the hippocampus. MethodsMale rats were given daily subcutaneous injections of nicotine at doses of 0.25, 2 or 4mg/kg body weight for 28 days. Animals were euthanized by cervical dislocation at the end of administration. Brains were excised and processed for histochemical demonstration of AChE and immunohistochemical studies of Ki67, GFAP and NSE. ResultsThere was significant decrease (P<0.001) in AChE positive cells in the hippocampus and striatum following 2 and 4mg/kg nicotine but not at 0.25mg/kg. Nicotine treatment at 0.25 and 4mg/kg significantly decrease (P<0.05) immunoreactivity of Ki67 and NSE in DG. Contrastingly, 2mg/kg nicotine did not alter Ki67 immunoreactivity but rather significantly increased (P<0.05) NSE immunoreactivity in DG compared to control. ConclusionThis study suggests that nicotine may inhibit AChE activities in the brain, thereby having a direct or indirect influence on prevention of central acetylcholine degradation, as well as either improve or retard maturation adult born neurons in DG, at different doses.

Coronary Injury Score Correlates with Proliferating Cells and Alpha-Smooth Muscle Actin Expression in Stented Porcine Coronary Arteries.

Neointimal formation and cell proliferation resulting into in-stent restenosis is a major pathophysiological event following the deployment of stents in the coronary arteries. In this study, we assessed the degree of injury, based on damage to internal elastic lamina, media, external elastic lamina, and adventitia following the intravascular stenting, and its relationship with the degree of smooth muscle cell proliferation. We examined the smooth muscle cell proliferation and their phenotype at different levels of stent injury in the coronary arteries of domestic swine fed a normal swine diet. Five weeks after stent implantation, swine with and without stents were euthanized and coronaries were excised. Arteries were embedded in methyl methacrylate and sections were stained with H&E, trichrome, and Movat’s pentachrome. The expression of Ki67, α-smooth muscle actin (SMA), vimentin, and HMGB1 was evaluated by immunofluorescence. There was a positive correlation between percent area stenosis and injury score. The distribution of SMA and vimentin was correlated with the degree of arterial injury such that arteries that had an injury score >2 did not have immunoreactivity to SMA in the neointimal cells near the stent struts, but these neointimal cells were positive for vimentin, suggesting a change in the smooth muscle cell phenotype. The Ki67 and HMGB1 immunoreactivity was highly correlated with the fragmentation of the IEL and injury in the tunica media. Thus, the extent of coronary arterial injury during interventional procedure will dictate the degree of neointimal hyperplasia, in-stent restenosis, and smooth muscle cell phenotype.

Effects of Physalis peruviana L on Toxicity and Lung Cancer Induction by Nicotine Derived Nitrosamine Ketone in Rats.

Nicotine-derived nitrosamine ketone (NNK) is considered a key tobacco smoke carcinogen inducing lung tumors. Physalis peruviana L (harankash) is considered one plant with marked health benefits. This study aimed to evaluate Physalis peruviana L effect on the toxic effect of NNK induced lung cancer in the rats by using pulmonary histopathological, immunohistochemical and DNA flow cytometric analyses. Sixty adult male rats were divided into four groups, each consisting of fifteen animals. The first group received saline, the second received two successive toxic doses of NNK only while the third received two successive toxic doses of NNK with a single daily dose of Physalis peruviana L. The fourth group received a single daily dose of Physalis peruviana L only. Toxic doses of NNK induced hyperplasia and adenocarcinoma in the lung and positive immunoreactivity for Ki-67 and p53 staining with disturbance of the lung DNA content. Administration of Physalis peruviana L with NNK led to a mild pulmonary hyperplasia and weak expression of Ki-67 and p53 with an improvement in the lung DNA content. Physalis peruviana L may protect against NNK induced lung carcinogenesis due to its antioxidant and anti-proliferative effects.

Morphological and Immunohistochemical Characterization of Canine Osteosarcoma Spheroid Cell Cultures.

SummarySpheroid cell culture emerges as powerful in vitro tool for experimental tumour research. In this study, we established a scaffold‐free three‐dimensional spheroid system built from canine osteosarcoma (OS) cells (D17). Spheroids (7, 14 and 19 days of cultivation) and monolayer cultures (2 and 7 days of cultivation) were evaluated and compared on light and electron microscopy. Monolayer and spheroid cultures were tested for vimentin, cytokeratin, alkaline phosphatase, osteocalcin and collagen I by means of immunohistochemistry. The spheroid cell culture exhibited a distinct network of collagen I in particular after 19‐day cultivation, whereas in monolayer cultures, collagen I was arranged as a lamellar basal structure. Necrotic centres of large spheroids, as observed in 14‐ and 19‐day cultures, were characterized by significant amounts of osteocalcin. Proliferative activity as determined by Ki‐67 immunoreactivity showed an even distribution in two‐dimensional cultures. In spheroids, proliferation was predominating in the peripheral areas. Metastasis‐associated markers ezrin and S100A4 were shown to be continuously expressed in monolayer and spheroid cultures. We conclude that the scaffold‐free spheroid system from canine OS cells has the ability to mimic the architecture of the in vivo tumour, in particular cell–cell and cell–matrix interactions.

An immunohistochemical study on the expression of sex steroid receptors, Ki-67 and cytokeratins 7 and 20 in feline endometrial adenocarcinomas.

BackgroundEndometrial adenocarcinomas are a rare type of tumour in cats. Though different morphologies have been reported, the most frequent histological type of feline endometrial adenocarcinoma (FEA) is the papillary serous. Characterization of molecular markers expression in FEA may contribute to clarify the pathogenesis of these tumours and to assess the differences between normal endometrium and FEA regarding the expression pattern of several proteins. Therefore, this study aimed to evaluate the immunohistochemical profile of a wide panel of antibodies (specific for ER-α, PR, Ki-67, CK7 and CK20) in twenty-four cases of FEA. Comparisons were made between FEA and feline normal cyclic endometrium in follicular (n = 13) and luteal (n = 10) stages. Except for Ki-67, all other molecular markers were assessed independently for the intensity of immunolabeling and for the percentage of cells expressing the protein.ResultsThis study showed that in FEA a loss of expression occurs for ER-α (P ≤ 0.0001) and less markedly also for PR. The lost in sex steroid receptors concerns a decrease in both the proportion of labelled cells and the intensity of immunolabelling (P = 0.002 and P = 0.024, respectively). Proliferative activity, estimated via Ki-67 immunoreaction, significantly increased in FEA as compared to normal endometrium (P ≤ 0.0001). Feline endometrial adenocarcinomas maintained the CK7+/CK20+ status of normal endometrium. However, FEA showed decreased CK7 intensity of labelling compared to normal endometria (P ≤ 0.0001) and loss of CK20 expression, both in intensity (P ≤ 0.0001) and in percentage of positive cells (P = 0.01), compared to normal tissues.ConclusionsData gathered in this study suggest that proliferation in FEA accompanies ER-α down-regulation, possibly following activation of pathways mediated by local growth factors. Moreover, FEA retains combined expression of CK7 and CK20, as evidenced in normal endometrial epithelia, although a decrease in CK7 expression was observed.

Abstract 3460: Fetal alcohol exposure increases susceptibility to carcinogenesis in the pituitary

Abstract The idea that exposure to adverse environmental conditions and lifestyle choices during pregnancy can result in fetal programming that underlies disease susceptibility in adulthood is now widely accepted. Fetal alcohol exposed offspring display many behavioral and physiological abnormalities including neuroendocrine-immune functions, which often carry over into their adult life. Since neuroendocrine-immune system is critically involved in the regulation of tumor surveillance, we determined whether fetal alcohol exposure increases the susceptibility to estrogen-induced pituitary prolactin-secreting tumors (prolactinomas), commonly occurring pituitary tumors in humans. Pregnant Fischer 344 rats were fed between gestational days 7 and 21 with a liquid diet containing alcohol (AF), pair-fed with isocaloric liquid diet (PF), or fed ad libitum with rat chow (AD). At 90 days of age, female offspring rats were ovariectomized and received a subcutaneous estradiol implant. These rats were sacrificed between 4 and 5 months after the estradiol implants. At the time of sacrifice, pituitaries of these animals were inspected for tumor and whole body were inspected for any tumor metastasis. Estradiol treatment increased pituitary weight about 5-folds in AD and PF treated groups and increased 20-30-folds in the AF treated group. Most tumors in the AF group were hemorrhagic. About 30% AF rats had some tumors in the non-pituitary sites. AD and PF rats did not show any non-pituitary site tumor. When AF rat pituitaries were grown in cultures, cells rapidly grew and formed colonies. Colony formation and rapid growth rate were not observed in cells of the pituitary from PF and AD rats. Histopathological evaluation revealed that tumors in AF group were more densely packed cells as compare to the PF and AD groups who showed uniform cells with abundant cytoplasm. Pituitary tumor from alcohol exposed animals showed strong nuclear p53 and monoclonal Ki67 immunoreactivity in almost all tumor cells. Significantly higher mRNA levels of hemorrhage-associated genes (VEGF and MMP-9) were also observed in pituitary tumor tissues from AF group as compare with PF and AD groups. Tumor cells showed positivity to prolactin staining but showed negativity to other pituitary hormones staining. Histological evaluation of the pituitary tissues revealed that tumors were prolactin producing in all groups, and tumors in AF pituitaries were highly proliferative. These data provide evidence for aggressive, possible neoplastic, prolactinoma development in the pituitary after estrogen treatment in fetal alcohol exposed female rats. (This work is supported by a National Institute of Health grant R01 AA11591). Citation Format: Shaima Jabbar, George Maglakelidze, Dipak K. Sarkar. Fetal alcohol exposure increases susceptibility to carcinogenesis in the pituitary. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3460. doi:10.1158/1538-7445.AM2015-3460

Abstract 4000: The increase of oncogenic miRNA expression in tongue carcinogenesis of a mouse model

Abstract Oral carcinoma is one of the leading causes of cancer death in the world. To develop biomarkers for early detection may bestow substantial benefits in diagnosis and the prevention of tumor progression. An animal model simulating the human pathogenesis will also be useful for developing therapeutic strategies. miRNAs are short, non-coding RNAs, which play important roles in neoplastic process. The detection of biomarkers in body fluid may enable non-invasive diagnostic approaches. This study used mouse chemical carcinogenesis model to investigate the disruption of miRNA expression in oral tongue tissues, and to explore the miRNA level in saliva and blood during pathogenesis. Mice were fed with 4-Nitroquinoline 1-Oxide (4NQO) in drinking water for 12 weeks and were kept for extended periods for tumor induction. The histological examination showed the consecutive increase in the severity of epithelial pathogenesis from hyperkeratosis, hyperplasia to epithelial dysplasia and squamous tumors following the increase of 4NQO exposure. The increase of miR-21 and miR-31 staining, as well as p53, pAKT and Ki-67 immunoreactivity parallels the severity of epithelial pathogenesis in tongue tissues. A progressive increase of multiple oncogenic miRNAs in both saliva and blood samples was also noted. The increase of miR-21, miR-31 and miR-372 in the saliva and the increase of miR-146a and miR-184 in the blood sample were particularly eminent during the field cancerization process of tongue. In addition, the dysregulation of these oncogenic miRNAs and other molecular events in this model are similar to the disruption being identified in human counterparts. As these miRNAs are functionally oncogenic, their increase in the saliva and blood of mice may be valuable biomarkers to develop diagnosis and prevention strategies against oral carcinomas. Keywords: chemical, carcinoma, miRNA, mouse, mouth Note: This abstract was not presented at the meeting. Citation Format: YUYU KAO, Shu-Chun Lin, Kuo-Wei Chang. The increase of oncogenic miRNA expression in tongue carcinogenesis of a mouse model. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4000. doi:10.1158/1538-7445.AM2015-4000

CRABP1 is associated with a poor prognosis in breast cancer: adding to the complexity of breast cancer cell response to retinoic acid.

BackgroundClinical trials designed to test the efficacy of retinoic acid (RA) as an adjuvant for the treatment of solid cancers have been disappointing, primarily due to RA resistance. Estrogen receptor (ER)-negative breast cancer cells are more resistant to RA than ER-positive cells. The expression and subcellular distribution of two RA-binding proteins, FABP5 and CRABP2, has already been shown to play critical roles in breast cancer cell response to RA. CRABP1, a third member of the RA-binding protein family, has not previously been investigated as a possible mediator of RA action in breast cancer.MethodsCRABP1 and CRABP2 expression in primary breast tumor tissues was analyzed using gene expression and tissue microarrays. CRABP1 levels were manipulated using siRNAs and by transient overexpression. RA-induced subcellular translocation of CRABPs was examined by immunofluorescence microscopy and immunoblotting. RA-induced transactivation of RAR was analyzed using a RA response element (RARE)-driven luciferase reporter system. Effects of CRABP1 expression and RA treatment on downstream gene expression were investigated by semi-quantitative RT-PCR analysis.ResultsCompared to normal mammary tissues, CRABP1 expression is significantly down-regulated in ER+ breast tumors, but maintained in triple-negative breast cancers. Elevated CRABP1 levels are associated with poor patient prognosis, high Ki67 immunoreactivity and high tumor grade in breast cancer. The prognostic significance of CRABP1 is attributed to its cytoplasmic localization. We demonstrate that CRABP1 expression attenuates RA-induced cell growth arrest and inhibits RA signalling in breast cancer cells by sequestering RA in the cytoplasm. We also show that CRABP1 affects the expression of genes involved in RA biosynthesis, trafficking and metabolism.ConclusionsCRABP1 is an adverse factor for clinical outcome in triple-negative breast cancer and a potent inhibitor of RA signalling in breast cancer cells. Our data indicate that CRABP1, in conjunction with previously identified CRABP2 and FABP5, plays a key role in breast cancer cell response to RA. We propose that these three RA-binding proteins can serve as biomarkers for predicting triple-negative breast cancer response to RA, with elevated levels of either cytoplasmic CRABP1 or FABP5 associated with RA resistance, and elevated levels of nuclear CRABP2 associated with sensitivity to RA.Electronic supplementary materialThe online version of this article (doi:10.1186/s12943-015-0380-7) contains supplementary material, which is available to authorized users.

Enhanced nonsynaptic epileptiform activity in the dentate gyrus after kainate-induced status epilepticus

Understanding the mechanisms that influence brain excitability and synchronization provides hope that epileptic seizures can be controlled. In this scenario, non-synaptic mechanisms have a critical role in seizure activity. The contribution of ion transporters to the regulation of seizure-like activity has not been extensively studied. Here, we examined how non-synaptic epileptiform activity (NEA) in the CA1 and dentate gyrus (DG) regions of the hippocampal formation were affected by kainic acid (KA) administration. NEA enhancement in the DG and suppression in area CA1 were associated with increased NKCC1 expression in neurons and severe neuronal loss accompanied by marked glial proliferation, respectively. Twenty-four hours after KA, the DG exhibited intense microglial activation that was associated with reduced cell density in the infra-pyramidal lamina; however, cellular density recovered 7days after KA. Intense Ki67 immunoreactivity was observed in the subgranular proliferative zone of the DG, which indicates new neuron incorporation into the granule layer. In addition, bumetanide, a selective inhibitor of neuronal Cl− uptake mediated by NKCC1, was used to confirm that the NKCC1 increase effectively contributed to NEA changes in the DG. Furthermore, 7days after KA, prominent NKCC1 staining was identified in the axon initial segments of granule cells, at the exact site where action potentials are preferentially initiated, which endowed these neurons with increased excitability. Taken together, our data suggest a key role of NKCC1 in NEA in the DG.

Solid Pseudopapillary Neoplasms of the Pancreas: a 19-Year Multicenter Experience in China

AimThe aim of this study was to determine the clinicopathological features, surgical management, and prognosis of solid pseudopapillary neoplasms (SPNs) of the pancreas. MethodsThis study conducted a retrospective analysis of 97 patients who underwent surgery for a pathologically confirmed SPN in five hospitals between January 1996 and December 2014. ResultsThe 97 cases included 93 female and 4 male patients, and the average age was 31.2 years. The tumor was located in the body or tail (70.1 %), the head (20.6 %), and the neck (9.3 %). All patients underwent surgical exploration, including distal pancreatectomy (63.9 %), pancreaticoduodenectomy (20.6 %) (partial portal vein or superior mesenteric vein resection and artificial vascular graft reconstruction performed in 4.1 % of the patients), central pancreatectomy (10.3 %), enucleation (5.2 %), and liver resection (1.0 %). 16.5 % of the patients had malignant tumors. The positive rate of Ki-67 was 66.7 % in patients diagnosed with a malignant neoplasm and was comparable to 8.4 % of the patients diagnosed to have a benign neoplasm (p < 0.001). After a median follow-up of 70.1 months, three patients had recurrence and one patient died of liver metastasis. ConclusionsSPN is a rare neoplasm with low malignant potential. Surgical resection is warranted even in the presence of local invasion or metastases as patients demonstrate excellent long-term survival. Positive immunoreactivity for Ki-67 may predict the malignant potential and poor outcome of SPNs.

18F]-FLT PET to predict early response to neoadjuvant therapy in KRAS wild-type rectal cancer: a pilot study

This pilot study evaluated the utility of 3'-deoxy-3'[18F]-fluorothymidine ([(18)F]-FLT) positron emission tomography (PET) to predict response to neoadjuvant therapy that included cetuximab in patients with wild-type KRAS rectal cancers. Baseline [(18)F]-FLT PET was collected prior to treatment initiation. Follow-up [(18)F]-FLT was collected after three weekly infusions of cetuximab, and following a combined regimen of cetuximab, 5-FU, and radiation. Imaging-matched biopsies were collected with each PET study. Diminished [(18)F]-FLT PET was observed in 3/4 of patients following cetuximab treatment alone and in all patients following combination therapy. Reduced [(18)F]-FLT PET following combination therapy predicted disease-free status at surgery. Overall, [(18)F]-FLT PET agreed with Ki67 immunoreactivity from biopsy samples and surgically resected tissue, and was predictive of treatment-induced rise in p27 levels. These results suggest that [(18)F]-FLT PET is a promising imaging biomarker to predict response to neoadjuvant therapy that included EGFR blockade with cetuximab in patients with rectal cancer.

Gangliocytic paraganglioma: a multi-institutional retrospective study in Japan.

BackgroundGangliocytic paraganglioma (GP) is an extremely rare benign tumor that commonly arises from the second part of the duodenum. Since GP exhibit neither prominent mitotic activity nor Ki-67 immunoreactivity, this tumor is often misdiagnosed as neuroendocrine tumor (NET) G1 (carcinoid tumor). However, patients with GP may have a better prognosis than patients with NET G1. This fact emphasizes the importance of differentiating GP from NET G1, but few studies have reported the epidemiology and histopathology of GP because of its rarity. To differentiate GP from NET G1 with ease, we conducted a multi-institutional retrospective study analyzing the morphometric and immunohistochemical features of this tumor.MethodsSince only a limited number of patients with GP could be identified in our institute, we conducted a multi-institutional retrospective study of GP in Japan, which was approved by the Ethics Committee of our medical institute. The obtained tissue sections underwent detailed morphometric and immunohistochemical analyses. Additionally, to differentiate GP from NET G1 with ease, immunohistochemical findings were compared.ResultsIn our examination of 12 cases of duodenal GP, we found that epithelioid cells of GP exhibited positive reactivity for progesterone receptor and pancreatic polypeptide, whereas tumor cells of NET G1 were completely negative reactivity for both. Additionally, although GP is considered to be an extremely rare NET, we found that four (40.0%) of the ten patients at our institute with duodenal NET G1 actually had GP.ConclusionsAlthough GP is regarded as a rare NET, our results suggest that it accounts for a substantial percentage of duodenal NETs. Additionally, confirmation of immunoreactivity for progesterone receptor and pancreatic polypeptide can assist in differentiating GP from NET G1.

Histopathogenesis of non-HPV-related differentiated oral squamous intraepithelial neoplasia.

A study of immunohistopathologic and cytohistopathologic changes of the parabasal/basal layers in the differentiated squamous intraepithelial neoplasia (DSIN) may elucidate the histopathogenesis and reveal changes aiding early diagnosis and grading of the lesion. A total of 55 consecutive resection specimens of nonbasaloid squamous cell carcinoma of the anterior oral cavity and 8 biopsies before resections displaying DSIN in the overlying squamous epithelium were examined. Squamous epithelium that is continuous/immediately adjacent to invasive squamous cell carcinoma (type 1) and the more peripheral (type 2) epithelium of resection specimens displayed consistent changes in the parabasal/basal layers: (A) cytologic atypia with proliferation of parabasal cells with downward expansion causing reactive proliferation of the basal cell layer in the early stage, invading the basal layer in the late stage; (B) disordered nuclear/cytoplasmic arrangement; (C) "Cobblestone" appearance. Immunoreactivity for TP53 and Ki67 was helpful in the diagnosis. The epithelial spectrum of changes decreased as one moved from type 1 to type 2 lesions. Five out of 8 biopsies showed type 1 lesions (followed by resection in a period of 11±6 mo) and 3 showed type 2 lesions (followed by resection in a period of 55±20 mo). In addition, resections were margin positive for type 2 lesions in 5 cases associated with recurrence at the site of resection during a period of 69±9 months. DSIN is characterized by a proliferation of neoplastic parabasal cells with dyskeratosis, downward expansion/pushing of the basal layer with elongation of rete ridges. We proposed grading of DSIN based on the changes of the parabasal/basal layers.

P53, KI-67, CD117 expression in gastrointestinal and pancreatic neuroendocrine tumours and evaluation of their correlation with clinicopathological and prognostic parameters.

Gastrointestinal and pancreatic neuroendocrine tumors (GEPNETs) originate from the cells of the endocrine system. Their molecular genetic mechanism of development and progression is complex and remains largely unknown. The purpose of this study was to review the gastrointestinal and pancreatic neuroendocrine tumors and to evaluate p53, Ki-67 and CD 117 expressions with their clinicopathological correlations. Twenty-one patients were reviewed and classified as having well-differentiated neuroendocrine neoplasm (WDET, Grade I), well-differentiated neuroendocrine carcinoma (WDEC, Grade II) and poorly differentiated neuroendocrine carcinoma (PDEC, Grade III). We performed immunohistochemical tests to characterize the expession of the immunoreactivity for synaptophysin, chromogranin, p53, Ki67 and CD 117. Median age of 21 patients was 43 years. Thirteen (61.9%) patients were male and eight (38.1%) patients were female. Tumors were located in the stomach (38.1%), appendix (38.1%), duodenum (4.8%), ileum (4.8%), colon (9.5%), and pancreas (4.8%). There was a statistically significant difference between well-differentiated endocrine neoplasm (Grade I), and well-differentiated endocrine carcinoma (WDEC, Grade II) and PDEC for Ki-67 >20% (p<0.001) (Pearson chi-square test). There was a statistically significant difference between WDET (Grade I), WDEC (Grade II) and PDEC (Grade III) for p53 positivity (p<0.05) (Pearson chi-square test).

Expression of Reg family genes in the gastrointestinal tract of mice treated with indomethacin.

Regenerating gene (Reg) family proteins, which are classified into four types, commonly act as trophic and/or antiapoptotic factors in gastrointestinal (GI) diseases. However, it remains unclear how these proteins coordinate their similar roles under such pathophysiological conditions. Here, we investigated the interrelationships of Reg family gene expression with mucosal cell proliferation and apoptosis in nonsteroidal anti-inflammatory drug (NSAID)-induced GI injury. GI injury was induced by subcutaneous injection of indomethacin into Reg I knockout (KO) and wild-type (WT) mice, and its severity was scored histopathologically. Temporal changes in the expression of Reg family genes, mucosal proliferation, and apoptosis were evaluated throughout the GI tract by real-time RT-PCR, Ki-67 immunoreactivity, and TUNEL assay, respectively. Reg I, Reg III family, and Reg IV were predominantly expressed in the upper, middle, and lower GI mucosa, respectively. Expression of Reg I and Reg III family genes was upregulated in specific portions of the GI tract after indomethacin treatment. Ki-67-positive epithelial cells were significantly decreased in the gastric and small-intestinal mucosa of Reg I KO mice under normal conditions. After treatment with indomethacin, the number of TUNEL-positive cells was significantly greater throughout the GI mucosa in Reg I KO mice than in WT mice. Expression of Reg I was independent of that of other Reg family genes in, not only normal GI tissues, but also indomethacin-induced GI lesions. Members of the Reg gene family show distinct profiles of expression in the GI tract, and Reg I independently plays a role in protecting the GI mucosa against NSAID-induced injury.

Influence of gender and time diet exposure on endocrine pancreas remodeling in response to high fat diet-induced metabolic disturbances in mice

In this study, we investigated a possible sexual dimorphism regarding metabolic response and structural and functional adaptations of the endocrine pancreas after exposure to a high-fat diet (HFd). On chow diet, male and female C57BL/6/JUnib mice showed similar metabolic and morphometric parameters, except that female islets displayed a relatively lower β-cell:non-β-cell ratio. After 30 days on HFd, both male and female mice showed increased weight gain, however only the males displayed glucose intolerance associated with high postprandial glycemia when compared to their controls. After 60 days on HFd, both genders became obese, hyperglycemic, hyperinsulinemic, insulin resistant and glucose intolerant, although the metabolic changes were more pronounced in males, while females displayed greater weight gain. In both genders, insulin resistance induced by HFd feeding was compensated by expansion of β-cell mass without changes in islet cytoarchitecture. Interestingly, we found a strong correlation between the degree of β-cell expansion and the levels of hyperglycemia in the fed state: male mice fed a 60d-HFd, showing higher glycemic levels also displayed a greater β-cell mass increase in comparison with female mice. Additionally, sexual dimorphism was also observed regarding the source of β-cell mass expansion following 60d-HFd: while in males, both hypertrophy and hyperplasia (revealed by morphometry and Ki67 immunoreaction) of β-cells were observed, female islets displayed only a significant increase in β-cell size. In conclusion, this study describes gender differences in metabolic response to high fat diet, paralleled by distinct compensatory morphometric changes in pancreatic islets.