SMER28 is a mTOR-independent small molecule enhancer of autophagy that protects mouse bone marrow and liver against radiotherapy.

Effective cytoprotectors that are selective for normal tissues could decrease radiotherapy and chemotherapy sequelae and facilitate the safe administration of higher radiation doses. This could improve the cure rates of radiotherapy for cancer patients. Autophagy is a cytoplasmic cellular process that is necessary for the clearance of damaged or aged proteins and organelles. It is a strong determinant of post-irradiation cell fate. In this study, we investigated the effect of the mTOR-independent small molecule enhancer of autophagy (SMER28) on mouse liver autophagy and post-irradiation recovery of mouse bone marrow and liver. SMER28 enhanced the autophagy flux and improved the survival of normal hepatocytes. This effect was specific for normal cells because SMER28 had no protective effect on hepatoma or other cancer cell line survival in vitro. In vivo subcutaneous administration of SMER28 protected mouse liver and bone marrow against radiation damage and facilitated survival of mice after lethal whole body or abdominal irradiation. These findings open a new field of research on autophagy-targeting radioprotectors with clinical applications in oncology, occupational, and space medicine.

Metabolic cooperation between co-cultured lung cancer cells and lung fibroblasts.

Cooperation of cancer cells with stromal cells, such as cancer-associated fibroblasts (CAFs), has been revealed as a mechanism sustaining cancer cell survival and growth. In the current study, we focus on the metabolic interactions of MRC5 lung fibroblasts with lung cancer cells (A549 and H1299) using co-culture experiments and studying changes of the metabolic protein expression profile and of their growth and migration abilities. Using western blotting, confocal microscopy and RT-PCR, we observed that in co-cultures MRC5 respond by upregulating pyruvate dehydrogenase (PDH) and the monocarboxylate transporter MCT1. In contrast, cancer cells increase the expression of glucose transporters (GLUT1), LDH5, PDH kinase and the levels of phosphorylated/inactivated pPDH. H1299 cells growing in the same culture medium with fibroblasts exhibit a 'metastasis-like' phenomenon by forming nests within the fibroblast area. LDH5 and pPDH were drastically upregulated in these nests. The growth rate of both MRC5 and cancer cells increased in co-cultures. Suppression of LDHA or PDK1 in cancer cells abrogates the stimulatory signal from cancer cells to fibroblasts. Incubation of MRC5 fibroblasts with lactate resulted in an increase of LDHB and of PDH expression. Silencing of PDH gene in fibroblasts, or silencing of PDK1 or LDHA gene in tumor cells, impedes cancer cell's migration ability. Overall, a metabolic cooperation between lung cancer cells and fibroblasts has been confirmed in the context of direct Warburg effect, thus the fibroblasts reinforce aerobic metabolism to support the intensified anaerobic glycolytic pathways exploited by cancer cells.

Differential effect of hypoxia and acidity on lung cancer cell and fibroblast metabolism.

This study examined the metabolic response of lung cancer cells and normal lung fibroblasts to hypoxia and acidity. GLUT1 and HXKII mRNA/protein expression was up-regulated under hypoxia in the MRC5 fibroblasts and in the A549 and H1299 lung cancer cell lines, indicating intensified glucose absorption and glycolysis. Under hypoxia, the LDHA mRNA and LDH5 protein levels increased in the cancer cells but not in the fibroblasts. Acidity suppressed the above-mentioned hypoxia effect. PDH-kinase-1 (PDK1 mRNA and protein) and inactive phosphorylated-PDH protein levels were induced under hypoxia in the cancer cells, whereas these were reduced in the MRC5 lung fibroblasts. In human tissue sections, the prevalent expression patterns supported the contrasting metabolic behavior of cancer cells vs. tumor fibroblasts. The monocarboxylate/lactate transporter 1 (MCT1) was up-regulated in all the cell lines under hypoxic conditions, but it was suppressed under acidic conditions. The mitochondrial DNA (mtDNA) content per cell decreased significantly in the A549 cancer cell line under hypoxia, but it increased in the MRC5 fibroblasts. Taking into account these findings, we suggest that, under hypoxia, cancer cells intensify the anaerobic direction in glycolysis, while normal fibroblasts prefer to seek energy by intensifying the aerobic use of the available oxygen.

Blocking LDHA glycolytic pathway sensitizes glioblastoma cells to radiation and temozolomide.

PURPOSE: Up-regulation of lactate dehydrogenase LDHA, is a frequent event in human malignancies and relate to poor postoperative outcome. In the current study we examined the hypothesis that LDHA and anaerobic glycolysis, may contribute to the resistance of glioblastoma to radiotherapy and to temozolomide. METHODS AND MATERIALS: The expression of LDH5 isoenzyme (fully encoded by the LDHA gene) was assessed in human glioblastoma tissues. Experimental in vitro studies involved the T98 and U87 glioblastoma cell lines. Their sensitivity to radiotherapy and to temozolomide, following silencing of LDHA gene or following exposure to the LDHA chemical inhibitor 'oxamate' and to the glycolysis inhibitor '2-deoxy-d-glucose' (2DG), was studied. RESULTS: Glioblastoma tissues showed strong cytoplasmic and nuclear LDH5 expression in 0-90% (median 20%) of the neoplastic cells. T98 and U87 cell lines showed that blocking glycolysis, either with LDHA gene silencing or exposure to oxamate (30 mM) and blockage of glycolysis with 2DG (500 µM), results in enhanced radiation sensitivity, an effect that was more robust in the T98 radioresistant cell line. Furthermore, all three glycolysis targeting methods, significantly sensitized both cell lines to Temozolomide. CONCLUSIONS: The current study provides evidence that a large subgroup of human glioblastomas are highly glycolytic, and that inhibitors of glycolysis, like LDHA targeting agents, may prove of therapeutic importance by enhancing the efficacy of radiotherapy and temozolomide against this lethal disease.

Expression of enzymes related to glucose metabolism in non-small cell lung cancer and prognosis.

Purpose/Aim: Cancer cells are addicted to glycolytic anaerobic pathways, in presence or in absence of a functional Krebs' cycle (phenomenon Warburg). This metabolic predilection relies on both extracellular (impaired vascularization and oxygenation) and intracellular (oncogenic activation of genes) causes. MATERIALS AND METHODS: We investigated the expression and prognostic relevance of enzymes involved in the glucose absorption and metabolism, monocarboxylate transporter (MCT) expression, MCT1 and MCT2, pentose pathway (Glucose-6-phospahte dehydrogenase G6PD), glycogene synthesis (glycogene synthase GYS1), glycolysis (Hexokinase HXKII, phosphofructokinase PFK1, fructose biphosphate aldolase), fate of pyruvate (pyruvate dehydrogenase PDH, phosphorylated pPDH, PDH kinase PDK1, lactate dehydrogenase LDH5 and LDH1) and key Kreb's cycle enzymes (citrate synthase CSynth and isocitrate dehydrogenase IDH). RESULTS: A strong overexpression of the above enzymes/proteins was noted in a varying percentage of cases examined. An interesting significant correlation between the enzymes involved in glycolysis and with the LDH5 was noted. Adenocarcinomas expressed higher levels of GLUT1 and MCT2 compared to other subtypes. Stage (p = 0.0001), aldolase (p = 0.004), LDH5 (p = 0.008), GLUT2 (p = 0.008), MCT2 (p = 0.009), GSYS1 (p = 0.04), and GLUT1 (p = 0.05) were significantly related with poor disease specific overall survival. In multivariate analysis stage (p = 0.001), LDH5 (p = 0.04), pPDH (p = 0.04), and aldolase (p = 0.04) were independent prognostic variables. CONCLUSION: It is concluded that an orchestrated activation of glucose absorption and metabolism towards anaerobic pathways characterize the majority of NSCLC, and this phenotype is strongly linked with an aggressive clinical behavior. This glycolytic addiction of lung cancer cell is revealed as a key therapeutic target.

Intensified autophagy compromises the efficacy of radiotherapy against prostate cancer.

INTRODUCTION: Radiotherapy is an equivalent alternative or complement to radical prostatectomy, with high therapeutic efficacy. High risk patients, however, experience high relapse rates, so that research on radio-sensitization is the most evident route to improve curability of this common disease. MATERIALS AND METHODS: In the current study we investigated the autophagic activity in a series of patients with localized prostate tumors treated with radical radiotherapy, using the LC3A and the LAMP2a proteins as markers of autophagosome and lysosome cellular content, respectively. The role of autophagy on prostate cancer cell line resistance to radiation was also examined. RESULTS: Using confocal microscopy on tissue biopsies, we showed that prostate cancer cells have, overall, high levels of LC3A and low levels of LAMP2a compared to normal prostate glands. Tumors with a 'highLC3A/lowLAMP2a' phenotype, suggestive of intensified lysosomal consumption, had a significantly poorer biochemical relapse free survival. The PC3 radioresistant cell line sustained remarkably its autophagic flux ability after radiation, while the DU145 radiosensitive one experiences a prolonged blockage of the autophagic process. This was assessed with aggresome accumulation detection and LC3A/LAMP2a double immunofluorescence, as well as with sequestrosome/p62 protein detection. By silencing the LC3A or LAMP2a expression, both cell lines became more sensitive to escalated doses of radiation. CONCLUSIONS: High base line autophagy activity and cell ability to sustain functional autophagy define resistance of prostate cancer cells to radiotherapy. This can be reversed by blocking up-regulated components of the autophagy pathway, which may prove of importance in the field of clinical radiotherapy.

Neutrophil extracellular traps promote differentiation and function of fibroblasts.

Neutrophil activation by inflammatory stimuli and the release of extracellular chromatin structures (neutrophil extracellular traps - NETs) have been implicated in inflammatory disorders. Herein, we demonstrate that NETs released by neutrophils treated either with fibrosis-related agents, such as cigarette smoke, magnesium silicate, bleomycin, or with generic NET inducers, such as phorbol 12-myristate 13-acetate, induced activation of lung fibroblasts (LFs) and differentiation into myofibroblast (MF) phenotype. Interestingly, the aforementioned agents or IL-17 (a primary initiator of inflammation/fibrosis) had no direct effect on LF activation and differentiation. MFs treated with NETs demonstrated increased connective tissue growth factor expression, collagen production, and proliferation/migration. These fibrotic effects were significantly decreased after degradation of NETs with DNase1, heparin or myeloperoxidase inhibitor, indicating the key role of NET-derived components in LF differentiation and function. Furthermore, IL-17 was expressed in NETs and promoted the fibrotic activity of differentiated LFs but not their differentiation, suggesting that priming by DNA and histones is essential for IL-17-driven fibrosis. Additionally, autophagy was identified as the orchestrator of NET formation, as shown by inhibition studies using bafilomycin A1 or wortmannin. The above findings were further supported by the detection of NETs in close proximity to alpha-smooth muscle actin (α-SMA)-expressing fibroblasts in biopsies from patients with fibrotic interstitial lung disease or from skin scar tissue. Together, these data suggest that both autophagy and NETs are involved not only in inflammation but also in the ensuing fibrosis and thus may represent potential therapeutic targets in human fibrotic diseases.

Primary squamous cell carcinoma of the ampulla of Vater.

CONTEXT: Squamous carcinoma of the ampulla of Vater is a very rare tumor with only three cases been reported so far. CASE REPORT: Here, we report the case of a 68-year-old man who presented with painless obstructive jaundice, general fatigue, loss of appetite and weight loss. Laboratory tests revealed hypochromic anemia. Total and direct bilirubin, alkaline phosphatase, liver enzymes, carbohydrate antigen 19-9 (CA 19-9) and carcinoembryonic antigen (CEA) were all elevated. Abdominal ultrasonography and computed tomography showed a distended gallbladder, dilatation of the intra- and extra-hepatic bile ducts and enlargement of the pancreatic head. Endoscopic retrograde cholangiopancreatography revealed a bulging papilla with infiltrative growth at the ampulla of Vater but endoscopic biopsies were inconclusive. The patient was treated with classical Whipple's pancreaticoduodenectomy. Histopathological examination showed a moderately differentiated squamous cell carcinoma. Multiple serial sectioning of the tumor specimen failed to detect an adenomatous component. Regional lymph nodes and resection margins were free of tumor and the disease was classified as stage IIA (T3N0M0) according to the TNM system. Adjuvant treatment was not given. Despite curative resection, multiple liver metastases developed after four months and the patient succumbed to progressive hepatic failure 5 months after the operation. CONCLUSION: Primary pure squamous cell carcinoma of the ampulla of Vater is a very rare histological type of carcinoma. Clinical characteristics and optimal treatment are obscure. Primary surgical treatment with curative intent should be performed although this type of carcinoma associates with dismal prognosis.

High DLL4 expression in tumour-associated vessels predicts for favorable radiotherapy outcome in locally advanced squamous cell head-neck cancer (HNSCC).

INTRODUCTION: Expression of the DLL4 (a notch pathway ligand) by tumor-associated endothelium is a postulated marker of vascular maturity and functionality. As vascular functionality is an important parameter defining chemotherapy and oxygen intra-tumoral distribution, we investigated the role of DLL4 expression in tumour vasculature in the efficacy of radio-chemotherapy for HNSCC patients. MATERIALS AND METHODS: Sixty-five biopsy specimens from HNSCC patients with inoperable disease were immunohistochemically examined using anti-CD31 (pan-endothelial cell marker) and anti-DLL4 antibodies and the vascular density (VD) was recorded. Patients were treated with platinum based hypofractionated accelerated conformal radiotherapy. The median follow-up period was 24 months (4-80 months). RESULTS: Using the 33rd and 66th percentiles cases were grouped in three categories of low, medium and high CD31+ or DLL4+ VD. The percentage of vessels expressing DLL4 (DLL4-ratio) ranged from 17 to 100 % (mean 71 %), showing substantial variation among cases. In accordance with previous published studies, a biphasic pattern of association of CD31+ VD with poor outcome was noted. Cases with a medium VD had a significantly better local relapse free survival (LRFS) compared to cases of high VD (p = 0.0005, HR 0.15) and of low VD (p = 0.02, HR 0.28). High DLL4/CD31 ratio defined improved LRFS in both these subgroups of poor prognosis. CONCLUSIONS: The expression of DLL4 is associated with reduced radio-resistance, presumably by reducing hypoxia and improving chemotherapy accessibility. Using the combination of CD31 and DLL4 staining, a classification is suggested so that HNSCCs are categorized in sub-groups to be targeted by different anti-angiogenic and hypoxia targeting agents.

Long-term angiogenic activity of free grafts and pedicle flap in a rabbit urethroplasty model.

PURPOSE: We studied the late angiogenic activity of free grafts and a pedicle flap in a rabbit urethroplasty model to determine whether angiogenic activity plays a role in late outcomes of urethral reconstruction in rabbits. METHODS: Twenty-eight rabbits were randomly divided into five groups according to the method used to bridge a urethral defect as an onlay patch: Control, simple closure of urethral defect (Group O1); free penile skin graft (FPSG, Group A1); buccal mucosal graft (BuMG, Group B1); bladder mucosal graft (BlMG, Group C1); and pedicle penile skin flap (PPSF, Group D1). Angiogenic activity of the patch on postoperative day 84 was assessed by immunohistochemistry. RESULTS: The angiogenic activity in Groups O1, A1, B1, C1, and D1 was 23.33 ± 4.92 (means ± SD), 42.89 ± 6.52, 55.78 ± 3.46, 53.61 ± 6.17, and 24.11 ± 9.07 vessels per optical field, respectively. There were statistically significant differences (p < .001) between Group O1 and A1 B1, C1, Group A1 and B1, C1, D1, Groups B1 and D1 and Groups C1 and D1, but not between Groups O1 and D1 (p = 1.000) and Groups B1 and C1 (p = .872). The long-term angiogenic activity of all the groups was significantly lower (p < .001) than in the corresponding early groups. CONCLUSIONS: Although the angiogenic activity of all the groups decreased in the late assessment, the buccal mucosal graft continued to exhibit elevated angiogenesis above bladder or skin (free or pedicle) graft. Therefore, buccal mucosal patch graft might be preferable because of its easier harvesting.

Lipophagy-Related Protein Perilipin-3 and Resistance of Prostate Cancer to Radiation Therapy.

PURPOSE: Radiation therapy is a principal treatment modality for localized and locally advanced prostate cancer (PCa). Metabolic alterations, including lipid metabolism, may reduce treatment efficacy, resulting in tumor relapse and poor therapeutic outcome. In the current study, we investigated the role of the lipophagy-related protein perilipin-3 (PLIN3) and the lysosomal acid lipase (LAL) in PCa response to radiation therapy. METHODS AND MATERIALS: We explored the in vitro and xenograft (in NOD SCID and R2G2 mice) response to radiation of either PLIN3-depleted or LAL-depleted hormone-refractory (DU145, PC3) and hormone-responsive (22Rv1) PCa cell lines. Moreover, we evaluated the clinical role of PLIN3 and LAL protein expression in a series of PCa tissue specimens from patients treated with radical radiation therapy. RESULTS: In vitro and in vivo experiments showed reduced proliferation and strong radiosensitization of all studied PCa cell lines upon PLIN3 depletion. In vivo experiments demonstrated the significantly augmented radiation therapy efficacy upon PLIN3 depletion, resulting in extensive tissue necrosis. Overexpression of PLIN3 in tissue specimens was correlated with an increased MIB1 proliferation index, increased autophagy flux, reduced response to radiation therapy, and poor prognosis. The effect of LAL depletion on radiation therapy was of lesser importance. CONCLUSIONS: Assessment of PLIN3 expression may identify subgroups of patients with PCa who are less responsive to radiation therapy and at high risk of relapse after irradiation. Whether radiation therapy efficacy may be enhanced by concurrent autophagy or PLIN3 inhibition in this subgroup of patients demands clinical evaluation.

Lung autophagic response following exposure of mice to whole body irradiation, with and without amifostine.

PURPOSE: The effect of ionizing irradiation on the autophagic response of normal tissues is largely unexplored. Abnormal autophagic function may interfere the protein quality control leading to cell degeneration and dysfunction. This study investigates its effect on the autophagic machinery of normal mouse lung. METHODS AND MATERIALS: Mice were exposed to 6 Gy of whole body γ-radiation and sacrificed at various time points. The expression of MAP1LC3A/LC3A/Atg8, beclin-1, p62/sequestosome-1 and of the Bnip3 proteins was analyzed. RESULTS: Following irradiation, the LC3A-I and LC3A-II protein levels increased significantly at 72 h and 7 days. Strikingly, LC3A-II protein was increased (5.6-fold at 7 days; p<0.001) only in the cytosolic fraction, but remained unchanged in the membrane fraction. The p62 protein, was significantly increased in both supernatant and pellet fraction (p<0.001), suggesting an autophagosome turnover deregulation. These findings contrast the patterns of starvation-induced autophagy up-regulation. Beclin-1 levels remained unchanged. The Bnip3 protein was significantly increased at 8 h, but it sharply decreased at 72 h (p<0.05). Administration of amifostine (200 mg/kg), 30 min before irradiation, reversed all the LC3A and p62 findings on blots, suggesting restoration of the normal autophagic function. The LC3A and Beclin1 mRNA levels significantly declined following irradiation (p<0.01), whereas Bnip3 levels increased. CONCLUSIONS: It is suggested that irradiation induces dysfunction of the autophagic machinery in normal lung, characterized by decreased transcription of the LC3A/Beclin-1 mRNA and accumulation of the LC3A, and p62 proteins. Whether this is due to defective maturation or to aberrant degradation of the autophagosomes requires further investigation.

Autophagy patterns and prognosis in uveal melanomas.

Autophagy is a self-degradation mechanism by which cells recycle their own cytoplasmic constituents. It has been claimed that, under certain conditions, such a process may be associated with tumor progression. In this study, the autophagic activity was investigated in a series of 99 uveal melanomas after immunohistochemical staining for the autophagy-associated proteins MAP1LC3A and BECN1, most commonly known as LC3A and Beclin 1, respectively. These were assessed in parallel with the hypoxia-inducible factor 1α (HIF1A) and its downstream protein lactate dehydrogenase 5 (composed by five LDHA subunits). Increased autophagic reactivity, detected by MAP1LC3A or BECN1, was associated with intense pigmentation and tumor hypoxia. Uveal melanomas with extensive overexpression of BECN1 or those with underexpression of this protein were associated with the worst prognosis, but the former manifested metastases much earlier than the latter; only 58% of patients with extensive BECN1 overexpression were alive at 4 years, compared with 80% of patients with underexpressed patterns. It is concluded that autophagy is commonly upregulated in uveal melanomas, and may be associated with hypoxia and intense pigmentation. There is a strong association between extensive BECN1 overexpression and early metastases/poor prognosis, and between underexpression of this protein and late metastases/better prognosis.

LC3A-positive light microscopy detected patterns of autophagy and prognosis in operable breast carcinomas.

Autophagy is a self-degradation mechanism by which cells recycle their own cytoplasmic constituents and dispose of excess or defective organelles after starvation and oxygen deprivation. An antibody to the microtubule-associated protein 1 light chain 3 (LC3A), recognizing both the soluble (LC3A-I) and the membrane-bound form (LC3A-II) of the protein, was used to detect autophagic activity in 102 breast carcinomas. Three distinct patterns were recognized: (1) diffuse cytoplasmic, (2) cytoplasmic/juxta-nuclear, and (3) "stone-like" pattern--dense, rounded, amorphous structures, 5 microm on average, typically enclosed within cytoplasmic vacuoles. The diffuse cytoplasmic pattern showed a direct association with estrogen and progesterone receptor expression. The juxta-nuclear pattern indicated a similar association with hormone receptors, an inverse association with tumor size, and a favorable prognosis. By contrast, an increased number of stone-like structures, probably representing an excessive autophagic response, was related to high-grade tumors and a less favorable outcome. Interestingly, 60 additional epithelial tumors of nonbreast origin disclosed identical autophagic patterns, and so did MDA231 breast cancer xenografts and HCT116 colon tumor spheroids (also analyzed by electron microscopy). Moreover, MCF-7 human breast cancer cell lines confirmed induction of LC3A by anoxia and Thapsigargin. It is concluded that autophagy can be readily recognized in breast carcinomas by light microscopy, after immunohistochemical staining with LC3A, but the significance of the various patterns expressed would need further evaluation.

Serum VEGF levels and tissue activation of VEGFR2/KDR receptors in patients with breast and gynecologic cancer.

OBJECTIVES: Vascular endothelial cell growth factor (VEGF) plays an important role in the biology of gynecological cancer, usually linked with aggressive tumour behaviour and a poor postoperative outcome. Yet, its role in benign breast/gynecological conditions is less clear. METHODS: Serum VEGF was analysed in a series of 49 patients with gynecological cancer and 61 patients with benign disease and compared to those of 12 normal female subjects. In addition, the activation status of VEGFR2/KDR receptors was investigated in formalin-fixed paraffin embedded tissues and related to VEGF. RESULTS: Mean serum levels of VEGF were significantly higher in patients with breast, endometrial and ovarian cancer compared to healthy controls and those with benign breast/gynecologic disease in the respective organs. A similar trend was noted in some cases of simple endometrial hyperplasia, fibroadenoma and fibrocystic disease of the breast. The expression of phosphorylated VEGFR2/KDR receptors was higher in breast, endometrial, ovarian cancer in patients with high VEGF serum levels and this reached a level of statistical significance when all malignancies were combined. CONCLUSIONS: Serum VEGF levels are increased in patients with breast and gynecological malignancies, but this can not be considered pathognomonic for cancer as it is also increased in certain benign conditions, including cases of fibroadenoma, fibrocystic disease of breast and simple endometrial hyperplasia. Furthermore, high serum VEGF levels are closely related to the activation status of the VEGFR2/KDR receptor in cancer cells, indicating a stimulatory effect of serum VEGF on the VEGF pathway contributing to tumor progression.

High Beclin 1 expression defines a poor prognosis in endometrial adenocarcinomas.

OBJECTIVE: To investigate the prognostic role of Beclin 1 in endometrial adenocarcinomas of the endometrioid cell type. Beclin 1 is a known tumor suppressor gene, but its function may be altered under conditions of an accelerated autophagic activity, which provides additional energy to proliferating cells by recycling defective organelles and long-lived cytoplasmic proteins. MATERIALS AND METHODS: One hundred and fifty-five endometrioid adenocarcinomas were investigated for their autophagic activity using the monoclonal antibody Beclin 1 and an automated immunohistochemical technique. The extent of Beclin 1 expression was evaluated on a three-tier scale as follows: low (<10% positive tumor cells), intermediate (between 10% and 50% positive tumor cells), and high (>50% positive tumor cells). The results were correlated with the degree of tumor differentiation, the depth of myometrial invasion and the overall 5-year survival. In addition, the endometrial tumors were immunostained with the hypoxia inducible factor 1α (HIF1α) and their expression was related to Beclin 1. RESULTS: A high Beclin 1 reactivity occurred in 18.1% of endometrial adenocarcinomas studied and was associated with high tumor grade, high myometrial invasion and a poor 5-year survival. It was also correlated positively with HIF1α. Of the remaining adenocarcinomas 29.7% were of intermediate Beclin 1 reactivity and 52.2% of low, but correlations with prognostic factors were insignificant. CONCLUSION: An increased Beclin 1 expression is connected with the most aggressive endometrioid adenocarcinomas, probably as a result of its strong association with tumor hypoxia.

LC3A-positive "stone-like" structures in cutaneous squamous cell carcinomas.

This study was set to investigate the relation between autophagic activity and the aggressiveness of cutaneous squamous cell carcinomas (SCC), as indicated by tumor thickness and proliferative activity. The anti-LC3A antibody, recognizing both the soluble and the autophagosome-bound forms of the protein, and a standard immunohistochemical technique were applied to 75 cutaneous SCC of variable tumor thickness. The study was complemented by staining for MIB1. Three patterns of LC3A reactivity were recognized: diffuse cytoplasmic, cytoplasmic/perinuclear, and "stone-like" structures (SLS), that is, large, rounded, densely stained amorphous material, 5 µm on average, enclosed within cytoplasmic vacuoles. Higher numbers of SLS were counted in >6-mm-thick SCC compared with the intermediate-thickness tumors (2.1-6 mm) and the <2-mm-thick tumors; the mean recorded values, being 8.8, 4.55, and 1.55, respectively, were statistically significant. The diffuse cytoplasmic staining showed a nearly inverse trend, whereas the perinuclear pattern, expressed in <10% of the total, was not evaluated. With regard to MIB1 proliferation index, this increased with tumor thickness and, in linear regression analysis, was directly linked with SLS counts and inversely with the cytoplasmic pattern. These data suggest that autophagic activity in SCC, when expressed as high LC3A/SLS counts, can be regarded as an indicator of tumor aggressiveness.

Patterns of LC3A Autophagy Protein Expression in Keratoacanthomas.

To investigate the expression patterns of autophagy marker light chain protein 3 (LC3A) in keratoacanthoma (KA). KAs are generally regarded as benign but malignant behavior, including rare metastases, may occur. 85 KAs were assessed for the LC3A autophagic protein by immunohistochemistry. Diffuse cytoplasmic staining and a "stone-like structure" (SLS) characterized positive expression. Thirty-four out of 85 KAs (40%) had diffuse cytoplasmic LC3A immunostaining (percentage of positive cells ranging from 5 to 60%). In contrast, only 4 of the 85 KAs (4.7%) expressed SLSs. Only one SLS was detected per histologic section of each tumor. The p53 oncoprotein was encountered in all cases with expression ranging from 1 to 90% of cells (median 30%). The Ki-67 index was expressed in 63 cases (74% of cases; range 1-50% of cells; median value 5%). Neither of these two parameters nor diffuse cytoplasmic LC3A staining was significantly correlated with SLS expression or lack thereof. Expression of SLSs, a hallmark of malignancy, was found in 4.7% of KAs. Further study is necessary to determine whether this fraction represents the exceptional cases that harbor latent malignant potential.

Lactate dehydrogenase 5 expression in squamous cell head and neck cancer relates to prognosis following radical or postoperative radiotherapy.

OBJECTIVES: We assessed the expression and the prognostic role of lactate dehydrogenase 5 (LDH5, the major LDH isoenzyme involved in anaerobic glycolysis) in patients with squamous cell head and neck cancer (SCHNC). METHODS: LDH5 was assessed immunohistochemically in whole tissue sections from 141 patients with SCHNC. Of these, 102 were subjected to surgery with (90 patients) or without (12 patients) postoperative radiotherapy (group A), while 39 patients were treated with radical radiotherapy (group B). RESULTS: Mixed nuclear/cytoplasmic LDH5 expression was detected in 72.5% of group A and 61.5% of group B patients. This was significantly related to T4-stage (p = 0.04) and hypoxia-inducible factor-1alpha (HIF-1alpha) expression (p = 0.002). In group A, high LDH5 was linked with poorer distant metastasis-free survival (p = 0.01) and disease-specific overall survival (OS; p = 0.009). In multivariate analysis, LDH5 (p = 0.002) and HIF-1alpha (p = 0.01) were independently linked with distant metastasis. LDH5 was also linked with death events (p = 0.005). In group B, high LDH5 expression was significantly associated with poorer local relapse-free survival (p = 0.009) and OS (p = 0.01). In multivariate analysis, only T stage was a significant predictor of death events (p = 0.04). CONCLUSIONS: LDH5 is highly expressed in SCHNC and is linked with local relapse, survival and distant metastasis, suggesting that LDH5 is a marker of radioresistance and a target for therapeutic interventions.

Erythropoietin receptors in endometrial carcinoma as related to HIF1{alpha} and VEGF expression.

Erythropoietin receptors (EpoRs) are expressed in a large percentage of cells in many human malignancies, including endometrial adenocarcinoma. In such tumors, administration of recombinant human erythropoietin (rhEpo) during radiotherapy and chemotherapy may oppose tumor progression by interfering with growth and invasion pathways. In the present study, a strong EpoR expression was demonstrated in 58.8% of 72 stage I endometrial adenocarcinomas, and this pattern was linked with a high degree of tumor differentiation (p=0.01), deep myometrial invasion (p=0.04) and, marginally, with poor prognosis (p=0.06). In addition, a strong association with the immunohistochemical expression of hypoxia-inducible factor 1alpha (HIF1alpha) and the downstream angiogenic protein vascular endothelial growth factor (VEGF) was noted. In multivariate analysis, HIF1alpha, but not EpoR, was associated with the depth of myometrial invasion (p=0.04) and marginally with prognosis (p=0.07). It is concluded that EpoR are common constituents of endometrial adenocarcinomas and are related to tumor aggressiveness, although this is probably a result of their involvement in an active HIF pathway.