Anti-PEc: Development of a novel monoclonal antibody against prostate cancer.

BACKGROUND: The Ec peptide (PEc) that defines the IGF-1Ec isoform, is associated with prostate cancer progression by inducing proliferation, metastases, and tumour repair. On these grounds, an anti-PEc monoclonal antibody (MAb) was developed. Our objective is to examine the effects of this antibody on prostate cancer and its possible side effects. METHODS: The effects of the obtained MAb were examined in cancer and non-cancerous cell lines (unmodified and modified either to overexpress or silence PEc) and in tumours in SCID mice injected with unmodified prostate cancer cells. The investigation was obtained with respect to cellular proliferation, migration, invasion, toxicity to tumours, effects on the cell cycle, immune response activation, effects on mesenchymal stem cell mobilisation leading to tumour repair, tissue distribution, and toxicity to mice. RESULTS: Anti-PEc MAb treatment led to a significant decrease in cellular proliferation, migration, and invasion compared to the untreated cell lines (p < 0.0005 in every case). Mechanistically, these effects were associated with the downregulation of pERK1/2 and vimentin and the upregulation of E-Cadherin. In vivo, anti-PEc MAb treatment was associated with a significant decrease in tumour size and metastases rate (p < 0.0005 in every case) by reversing the tumours mesenchymal phenotype. It also inhibited host stem cell mobilisation towards the tumour, leading to apoptosis. Anti-PEc MAb assessment in respect to distribution and toxicity, indicated its tumour specificity and lack of toxicity. CONCLUSIONS: These data indicate that the therapeutic targeting of PEc with the anti-PEc MAb may have considerable clinical benefit for prostate cancer patients.

AGAPP: efficacy of first-line cisplatin, 5-fluorouracil with afatinib in inoperable gastric and gastroesophageal junction carcinomas. A Hellenic Cooperative Oncology Group study.

PURPOSE: Gastric cancer is the fifth most common neoplasm worldwide with high rates of mortality. Afatinib, a low molecular, irreversible potent inhibitor of ErbB trans-membrane receptor family, has shown promising results according to preclinical and phase I clinical trial data when combined with chemotherapy. We aimed at evaluating the safety and efficacy of the combination of cisplatin, 5FU with afatinib in molecularly unselected patients with advanced gastric cancer. METHODS: Patients with locally advanced or metastatic gastric/gastroesophageal junction adenocarcinoma received first line combination therapy of cisplatin, 5FU and afatinib every 21 days, followed by afatinib maintenance monotherapy. The primary endpoint was the Objective Response Rate (ORR); secondary endpoints included Overall Survival (OS), Progression Free Survival (PFS) and the safety profile. Unplanned exploratory analysis of HER2 and tumor mutational profile was performed. RESULTS: Among 55 patients (ITT population) enrolled, 19 (34.5%) achieved an objective tumor response; stable disease was observed in 16 patients (29.1%) and progressive disease in 10 patients (18.2%). The ORR in the per protocol population (PP) was 42.9%. Within a median follow-up of 56 months, the median PFS and OS in the ITT population was 5.0 and 8.7 months, respectively. Seven of the 47 HER2 informative cases carried HER2 positive tumors while TP53, BRCA2 and SMAD4 were the most frequently mutated genes. The most common toxicities were neutrophil count and white blood cell decrease occurring in 56.4% of patients, followed by anemia (50.9%), hyperglycemia (40%), and diarrhea (38.2%). CONCLUSIONS: The combination of cisplatin/5FU with afatinib did not surpass the benchmarks of efficacy of the contemporary therapeutic regimens that are being applied for the treatment of patients with advanced gastric cancer. However, the observed efficacy and the improved safety profile support that our administration schedule may be further investigated to overcome toxicity problems when integrating afatinib to cytotoxic chemotherapy. CLINICAL TRIAL REGISTRATION: NCT01743365.

Androgen Receptor and PIM1 Expression in Tumor Tissue of Patients With Triple-negative Breast Cancer.

BACKGROUND/AIM: Effective targeted therapies for triple-negative breast cancer (TNBC) are limited. In a subset of TNBC, androgen receptor (AR) plays an important role, while the human proviral integration site for Moloney murine leukemia virus-1 (PIM1) overexpression is also implicated. PIM1 kinases phosphorylate AR, thus regulating its transcriptional activity, regardless of the presence or not of androgens. We evaluated the expression of AR and PIM1 and their prognostic significance in TNBC. MATERIALS AND METHODS: AR and PIM1 transcripts were quantified by quantitative reverse transcription polymerase chain reaction in formalin-fixed paraffin-embedded tumor from 141 patients with TNBC. RESULTS: AR was expressed in 38.3%, PIM1 in 10.6%, while co-expression of AR and PIM1 was detected in 7/141 cases (5.0%). No prognostic significance of AR or PIM1 was reached for overall or disease-free survival. CONCLUSION: Co-expression of AR and PIM1 exists in only in a small percentage of patients with TNBC. The implications of this finding in the therapeutic management of patients with TNBC should be investigated in larger patient cohorts.

Expression of IGF-IEc Isoform in Renal Cell Carcinoma Tissues.

BACKGROUND/AIM: Insulin-like growth factor-I (IGF-I) regulates various aspects of cancer biology. There is a growing body of evidence regarding the potential distinct role of IGF-I isoforms, particularly of IGF-IEc, in the pathophysiology of various human cancer types, however, there are no studies which examined the expression of the different IGF-I isoforms in renal cell carcinoma (RCC). This study aimed to characterize the expression of IGF-IEc in human RCC tissues and investigated whether its expression is associated with the histopathological type of RCC as well as with the overall survival of patients. MATERIALS AND METHODS: Formalin-fixed paraffin-embedded renal tissue samples from 94 patients (58 males and 36 females) were assessed for IGF-IEc expression by immunohistochemistry. RESULTS: RCC tissues showed mainly cytoplasmic IGF-IEc staining but immunoreactivity of IGF-IEc was also localized in the cell membrane. Significantly lower IGF-IEc expression was found in clear cell RCC vs. all other histological types (p=0.010), and this remained significant after adjusting for tumor size, grade, stage, and mitotic index (p<0.05). No association was found between IGF-IEc expression level and overall survival of patients with RCC. CONCLUSION: The differential expression of IGF-IEc isoform among the RCC histopathological types may indicate its histological type-specific regulation and possibly suggests a discrete biological role of this isoform in the pathophysiology of RCC.

Expression of Kisspeptin (KISS1) and its Receptor GPR54 (KISS1R) in Prostate Cancer.

BACKGROUND/AIM: Prostate cancer (PCa) is the second most commonly diagnosed cancer in men. In contrast to localized disease, metastatic PCa leads to increased mortality. Kisspeptin (KISS1) functions as a metastasis suppressor in various cancers. The aim of this study was to detect the expression of KISS1 and its receptor GPR54 (KISS1R) in prostate cancer. MATERIALS AND METHODS: The expression of KISS1 and KISS1R was examined in prostate cancer tissue specimens after radical prostatectomy. RESULTS: A higher expression of KISS1 and KISS1R was shown in patients with localized tumors (Stage ≤IIb) compared to patients with advanced (Stage ≥III) tumor. High Gleason score PCa and higher prognostic groups patients showed a lower expression rate of both KISS1 and KISS1R. CONCLUSION: A down-regulation of KISS1-KISS1R system was detected in advanced prostate cancer. KISS1as tumor suppressor might be useful in the future for the diagnosis, risk assessment of prostate cancer progression, as well as a therapeutic target for aggressive tumors.

Glomerular expression of matrix metalloproteinases in systemic lupus erythematosus in association with activity index and renal function.

PURPOSE: The aim of this study was to examine the expression of matrix metalloproteinases (MMPs) MMP-1, MMP-2, MMP-3, MMP-9, and their specific tissue inhibitor TIMP-1 in kidney biopsies of patients with lupus nephritis (LN) and to investigate the relationship between MMPs, activity index, and renal function at the time of kidney biopsy. METHODS: We performed immunohistochemistry with monoclonal antibodies against MMP-1, MMP-2, MMP-3, MMP-9, and TIMP-1 in 58 kidney-biopsy specimens with LN (according to the 2004 ISN/RPS classification) and eight specimens from normal kidney tissue. We used clinical data of 36 patients at the time of kidney biopsy to evaluate the association between MMPs expression and renal function. RESULTS: We found increased MMP-1, MMP-2, and MMP-3 expression in LN glomeruli and a significant correlation with the activity features, with higher activity index score and worse renal function (p < .001). In particular, we have noticed a significant correlation of MMP-1 with leukocyte influx (OR:16.5 95%CI 4.3-62.5 p < .001), and MMP-3 with glomerular hypercellularity (OR:18.6 95%CI 4.8-72.8 p < .001). Moreover, we found a strong correlation of MMP-2 expression with fibrinoid necrosis and cellular crescents formation (OR:17.1 95%CI 4.3-67.7 p < .001). CONCLUSIONS: MMP expression in renal biopsy of patients with LN is increased and directly related to a highly active inflammatory response. Moreover, stronger MMP expression is associated with higher activity index and a more profound renal dysfunction.

Evaluation of the prognostic value of CD3, CD8, and FOXP3 mRNA expression in early-stage breast cancer patients treated with anthracycline-based adjuvant chemotherapy.

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) have been shown to be of prognostic value in several cancer types. In early breast cancer, TILs have a prognostic utility, as well, especially in HER2-positive and triple-negative breast cancer. TILs presence is broadly associated with improved survival; however, there is controversy regarding TILs subpopulations. PATIENTS AND METHODS: Early-stage breast cancer patients treated with anthracycline-based chemotherapy within two randomized trials were included in the study. We evaluated, by qRT-PCR, 826 tumor tissue samples for mRNA expression of CD3, CD8, and FOXP3 for potential prognostic significance in terms of disease-free survival (DFS) and overall survival (OS). RESULTS: After a median follow-up of 133.0 months, 255 patients (30.9%) had died and 314 (38.0%) had disease progression. In the univariate analysis, high CD3 and CD8 mRNA expression was found to be of favorable prognostic value for DFS (P = 0.007 and P = 0.016, respectively). In multivariate analyses, the association of high CD8 mRNA expression with increased DFS was retained (HR = 0.77, 95% CI 0.60-0.998, Wald's P = 0.048), whereas that of high CD3 mRNA expression was of marginal statistical significance (HR = 0.77, 95% CI 0.59-1.01, P = 0.059). Moreover, a significant interaction was observed between HER2 status and CD3 mRNA expression with respect to DFS (interaction P = 0.032). In the HER2-positive subgroup, the hazard ratio associated with high CD3 mRNA expression was of greater magnitude (HR = 0.48, 95% CI 0.30-0.76, P = 0.002) compared with the hazard ratio presented above, for the entire cohort. No significant findings were observed for FOXP3 in terms of DFS, while none of the studied markers were of prognostic value for OS. CONCLUSIONS: High CD3 and CD8 mRNA expression in early-stage breast cancer patients is of prognostic value for decreased risk of relapse and, in the future, could potentially be of importance in deciding the most appropriate therapeutic strategy in light of the recent immune-related treatment developments.

AMALTHEA: Prospective, Single-Arm Study of the Hellenic Cooperative Oncology Group (HeCOG) Evaluating Efficacy and Safety of First-Line FOLFIRI + Aflibercept for 6 Months Followed by Aflibercept Maintenance in Patients With Metastatic Colorectal Cancer.

BACKGROUND: The efficacy and safety of the FOLFIRI (leucovorin, 5-fluorouracil, irinotecan, and oxaliplatin) regimen combined with aflibercept has not been studied in the first-line management of patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: In the context of a prospective single-arm trial (NCT02129257), patients with mCRC received standard doses of a maximum of 12 cycles of FOLFIRI combined with aflibercept (4 mg/kg body weight delivered intravenously) every 2 weeks, followed by aflibercept maintenance. Endpoints were 12-month progression-free survival rate, efficacy, and toxicity. RESULTS: Seventy-three fit patients were enrolled onto the study between 2014 and 2016. Median relative dose intensities administered were 0.80 for irinotecan and 1.0 for aflibercept. The most common grade 3/4 adverse events were neutropenia (13 patients, 18%), febrile neutropenia (3 patients, 4%), diarrhea (11 patients, 15%), hypertension (19 patients, 26%), proteinuria (8 patients, 11%), infections (8 patients, 11%), and mucositis (6 patients, 8%), with no toxic deaths. The objective response rate was 46.6%, significantly associated with the presence of right-sided primary, synchronous metastases, and a relapse-free interval of < 12 months (odds ratio = 3.00, 2.92, and 3.75 respectively, P ≤ .05). Intermediate infiltration by stromal core lymphocytes correlated with progression-free survival (hazard ratio = 0.40, [95% confidence interval (CI), 0.19-0.83], P = .014). At a median follow-up of 24.5 months, 12-month progression-free survival rate was 21.9% (median overall survival 20.9 months [95% CI, 16.6-29], median progression-free survival 8.4 months [95% CI, 7.4-9.3]). CONCLUSION: The FOLFIRI + aflibercept regimen is active and tolerable; however, it failed to improve historical benchmarks of efficacy in chemonaive patients with mCRC. Preliminary data hint that this regimen has cytoreductive activity in disease with adverse biology.

Assessing the clinical utility of Wnt pathway markers in colorectal cancer.

PURPOSE: ß-catenin and AXIN2 play an important role in the Wnt signaling pathway. The aim of this study was to investigate ß-catenin and AXIN2 expression in colorectal cancer (CRC) and relate these findings with patients' clinicopathological features and prognosis. METHODS: 57 consecutive patients with surgically treated CRC were included in this study. Quantitative PCR and immunohistochemistry (IHC) analyses were performed to characterize the expression of the aforementioned markers in CRC tissues. RESULTS: ß-catenin overexpression in the nucleus was associated with advanced N stage CRCs (p=0.04). Multivariate Cox regression analysis showed that ß-catenin overexpression is an independent prognostic factor for overall survival (OS). A positive correlation between ß-catenin location and AXIN2 mRNA was observed. CONCLUSIONS: Nuclear ß-catenin is a valuable prognostic factor. AXIN2 is a component of the "Destruction Complex" and also a Wnt target gene. However, the clinical importance of AXIN2 expression in CRC remains unclear.

The COOH-terminus of the IGF-1Ec Isoform Enhances the Proliferation and Migration of Human MCF-7 Breast Cancer Cells.

BACKGROUND/AIM: The insulin-like growth factor-1 (IGF-1) signaling is well implicated in cancer biology, however the potential roles of the distinct IGF-1 isoforms in human malignancies are largely unknown. Recently, the carboxyl-terminal of the IGF-1Ec variant (hEc; 24aa) has been associated with osteosarcoma and prostate cancer. Herein, we investigated the potential role of hEc in breast cancer. MATERIALS AND METHODS: Synthetic hEc peptide was administrated to MCF-7 and MDA-MB-231 breast cancer cells. In addition MCF-7 cells were engineered to overexpress hEc. The proliferation and migratory capacities in response to hEc were analyzed using MTT, trypan blue and wound healing/scratch assays, while the activation of the ERK/AKT signaling pathways were investigated using phospho western blotting. RESULTS: We found that exogenous administration of hEc stimulated the proliferation of estrogen-responsive MCF-7, but not that of hormone-resistant MDA-MB-231 cells. In addition, MCF-7 cells stably-overexpressing hEc acquired an increased proliferation rate and migratory capacity, as well as, enhanced ERK1/2 phosphorylation, compared to mock and wild-type cells. CONCLUSION: hEc stimulates the proliferation and migration of MCF-7 breast cancer cells and enhances the intracellular ERK1/2 signaling.

Clinical evaluation of microRNA-145 expression in renal cell carcinoma: a promising molecular marker for discriminating and staging the clear cell histological subtype.

The vast majority of malignancies detected in renal parenchyma are diagnosed as renal cell carcinoma (RCC), whose subtype discrimination and determination of prognosis may contribute to the selection of the adequate therapy. Recently, a new class of small non-coding RNAs, known as microRNAs, has proven to be among the most promising biomarkers for providing this information. Herein, we sought to add up to this knowledge by evaluating the expression levels of microRNA-145 (miR-145) in RCC. For that purpose, total RNA from 58 cancerous and 44 adjacent non-cancerous renal tissues was firstly extracted and then polyadenylated and reverse transcribed to cDNA. MiR-145 levels were finally analyzed by developing and applying a highly sensitive real-time PCR protocol, while their clinical significance was determined via comprehensive statistical analysis. Our data showed that miR-145 was significantly downregulated in cancerous samples and could discriminate between clear cell and non-clear cell subtypes. Moreover, miR-145 expression was found to be correlated with primary tumor staging of cancerous samples, something also noticed in the clear cell RCC subset, in which miR-145 levels were negatively correlated with tumor size as well. Overall, these results indicate that miR-145 might constitute a promising molecular marker for RCC classification and staging.

Glomerular expression of matrix metalloproteinases in AL-amyloidosis and association with renal function at the time of kidney biopsy.

BACKGROUND: Matrix metalloproteinases (MMPs) have been implicated in the pathophysiology of various renal diseases, however, there are limited data regarding their role in renal AL-amyloidosis. In the present study, we evaluated the glomerular expression of MMPs in renal-biopsy specimens containing AL-amyloid deposits. We also examined the association of MMPs with renal function at the time of diagnostic renal biopsy. METHODS: We performed immunohistochemistry with monoclonal antibodies against MMP-1, MMP-2, MMP-3, MMP-9, and TIMP-1 in 19 kidney-biopsy specimens with AL-amyloidosis and 8 specimens from normal kidney tissue. We used clinical data of the patients at the time of kidney biopsy to evaluate the association between MMP expression and renal function. RESULTS: We found increased MMP-1 and MMP-3 expression within the amyloid deposits and adjacent tissues in > 50% of the amyloid-positive biopsies, whereas MMP-1 and MMP-3 were negative in control samples. In contrast, we found no significant glomerular MMP-2 and TIMP-1 expression in amyloid-containing or normal kidneys. MMP-9 expression was found in the glomerular basement membrane equally in AL-amyloidosis and control specimens. The presence of MMP-1 and MMP-3 in the glomeruli of patients with AL-amyloidosis correlated with worse renal function at the time of kidney biopsy. CONCLUSION: The findings of this study show increased glomerular expression of MMP-1 and MMP-3 in patients with AL-amyloidosis which is associated with worse renal function at the time of the kidney biopsy. Our results suggest an important role for MMP-1 and MMP-3 in the pathogenesis of renal damage in AL-amyloidosis.

L-DOPA decarboxylase mRNA levels provide high diagnostic accuracy and discrimination between clear cell and non-clear cell subtypes in renal cell carcinoma.

OBJECTIVES: Renal cell carcinoma (RCC) is the most frequent type of kidney cancer. RCC patients frequently present with arterial hypertension due to various causes, including intrarenal dopamine deficiency. L-DOPA decarboxylase (DDC) is the gene encoding the enzyme that catalyzes the biosynthesis of dopamine in humans. Several studies have shown that the expression levels of DDC are significantly deregulated in cancer. Thus, we herein sought to analyze the mRNA levels of DDC and evaluate their clinical significance in RCC. DESIGN AND METHODS: DDC levels were analyzed in 58 surgically resected RCC tumors and 44 adjacent non-cancerous renal tissue specimens via real-time PCR. Relative levels of DDC were estimated by applying the 2(-ΔΔC)T method, while their diagnostic accuracy and correlation with the clinicopathological features of RCC tumors were assessed by comprehensive statistical analysis. RESULTS: DDC mRNA levels were found to be dramatically downregulated (p<0.001) in RCC tumors, exhibiting remarkable diagnostic accuracy as assessed by ROC curve analysis (AUC: 0.910; p<0.001) and logistic regression (OR: 0.678; p=0.001). Likewise, DDC was found to be differentially expressed between clear cell RCC and the group of non-clear cell subtypes (p=0.001) consisted of papillary and chromophobe RCC specimens. Furthermore, a statistically significant inverse correlation was also observed when the mRNA levels of DDC were analyzed in relation to tumor grade (p=0.049). CONCLUSIONS: Our data showed that DDC constitutes a highly promising molecular marker for RCC, exhibiting remarkable diagnostic accuracy and potential to discriminate between clear cell and non-clear cell histological subtypes of RCC.

The role of KISS1/KISS1R system in tumor growth and invasion of differentiated thyroid cancer.

BACKGROUND/AIM: KISS1 protein and KISS1 receptor form a system that mainly promotes suppression of metastasis in various forms of cancer. We studied the relationship between KISS1/KISS1R expression and tumor progression in differentiated thyroid cancer (DTC). MATERIALS AND METHODS: Thirty-three patients diagnosed with DTC were included in the study. Immunohistochemical cytoplasmic expression was evaluated for KISS1 and cytoplasmic/membranous expression for KISS1R in thyroid cancer tissues. RESULTS: KISS1 expression was significantly higher in tumors with extrathyroidal invasion and advanced stage. KISS1R expression showed a statistically significant, moderate negative correlation with tumor size. CONCLUSION: Increased expression of KISS1 is possibly acquired to prevent further tumor invasiveness and formation of local or distant metastasis. It appears that malignant cells in DTC express increased levels of KISS1 as the tumor invades extrathyroidal tissues. Decreased expression of KISS1R seems to attenuate signaling of the KISS1/KISS1R system, possibly leading to tumor growth.

Oncogenic Role of the Ec Peptide of the IGF-1Ec Isoform in Prostate Cancer.

IGF-1 is one of the key molecules in cancer biology; however, little is known about the role of the preferential expression of the premature IGF-1 isoforms in prostate cancer. We have examined the role of the cleaved COO- terminal peptide (PEc) of the third IGF-1 isoform, IGF-1Ec, in prostate cancer. Our evidence suggests that endogenously produced PEc induces cellular proliferation in the human prostate cancer cells (PC-3) in vitro and in vivo, by activating the ERK1/2 pathway in an autocrine/paracrine manner. PEc overexpressing cells and tumors presented evidence of epithelial to mesenchymal transition, whereas the orthotopic injection of PEc-overexpressing, normal prostate epithelium cells (HPrEC) in SCID mice was associated with increased metastatic rate. In humans, the IGF-1Ec expression was detected in prostate cancer biopsies, where its expression correlates with tumor stage. Our data describes the action of PEc in prostate cancer biology and defines its potential role in tumor growth, progression and metastasis.

In-depth proteomic delineation of the colorectal cancer exoproteome: Mechanistic insight and identification of potential biomarkers.

Systemic mining of cancer exoproteome/secretome has emerged as a pivotal strategy for delineation of molecular pathways with mechanistic importance in cancer development, as well as the discovery of diagnostic/prognostic biomarkers. Although major advances in diagnostic and therapeutic management of colorectal cancer have been underscored in the last decade, this cancer still remains the second leading cause of cancer-related deaths in the developed world. Despite previous studies on deciphering the colorectal cancer exoproteome, such studies lack adequate depth and robustness due to technological limitations. Here, using a well-established LC-MS/MS method on an LTQ-Orbitrap mass spectrometer, we extensively delineated the exoproteome of 12 colon cancer cell lines. In total, 2979 non-redundant proteins were identified with a minimum of two peptides, of which ~62% were extracellular or cell membrane-bound, based on prediction software. To further characterize this dataset and identify clinical opportunities, first, we investigated overrepresented molecular concepts of interest via enrichment map analysis and second, we demonstrated translational importance of certain proteins, such as olfactomedin-4 and kallikrein-related peptidases-6 and -10, by investigating their expression levels in patient tissues and/or fluids. Overall, the present study details a comprehensive colorectal cancer exoproteome dataset, and may be used as future platform for biomarker discovery, and hypothesis-generating studies. BIOLOGICAL SIGNIFICANCE: This article represents one of the most extensive and comprehensive proteomic datasets regarding the secreted/extracellular proteome of colorectal cancer cell lines. The reported datasets may form a platform for a plethora of future, discovery-based or hypothesis-generating studies, attempting to either delineate putative cancer biomarkers for CRC, or elucidate questions of mechanistic importance (e.g. investigation of deregulated pathways for CRC progression).

Kiss-1/GPR54 protein expression in breast cancer.

BACKGROUND: Numerous studies have shown that the Kiss-1 gene countervails the metastatic aptitude of several cancer cell lines and solid-tumor neoplasias. However, there still remains ambiguity regarding its role in breast cancer and literature has arisen asserting that Kiss-1 expression may be linked to an aggressive phenotype and malignant progression. Herein, we investigated the protein expression of Kiss-1 and its receptor GPR54 in breast cancer tissues compared to non-cancerous mammary tissues. MATERIALS AND METHODS: Paraffin-fixed cancer tissues from 43 women with resected breast adenocarcinomas and 11 specimens derived from women suffering from fibrocystic disease, serving as controls, were immunostained with Kiss-1 and GPR54 antibodies. RESULTS: Kiss-1 and GPR54 protein expression levels were significantly higher in breast cancer compared to fibrocystic tissues (p<0.05). No significant correlation was established between Kiss-1 or GRP54 expression and tumor grade, tumor size, lymph node positivity, histological type or ER status. Kiss-1 expression significantly and positively correlated with GPR54 expression in both breast cancer and fibrocystic disease specimens. CONCLUSION: Kiss-1/GPR54 expression was found to be significantly higher in breast cancer compared to non-malignant mammary tissues.

IGF-IEc expression is associated with advanced clinical and pathological stage of prostate cancer.

BACKGROUND: Recent evidence suggests a role for the insulin-like growth factor-1Ec (IGF-IEc) transcript variant in cancer biology. The aim of the present study was to investigate whether IGF-IEc expression is associated with prostate cancer stage. MATERIALS AND METHODS: Formalin-fixed and paraffin-embedded prostate cancer surgical specimens from 83 patients were assessed by immunohistochemistry for IGF-IEc expression. RESULTS: Normal prostate epithelium was negative or demonstrated mild IGF-IEc cytoplasmic expression whereas prostate cancer exhibited mild to strong cytoplasmic immunoexpression. The mean IGF-1Ec expression, was significantly lower (p=0.004) in localized (stage ≤ IIb) prostate cancer, compared to locally advanced tumors (stage ≥ III). Only one out of 83 (1.2%) prostate cancer samples was completely negative for IGF-IEc. A weak-positive correlation was also observed between IGF-IEc expression levels and Gleason score (r=0.247; p=0.024). CONCLUSION: The present data demonstrate that the expression of IGF-IEc is positively-associated with more advanced stage and higher Gleason score of prostate carcinomas.

Evaluation and prognostic significance of human tissue kallikrein-related peptidase 10 (KLK10) in colorectal cancer.

The prognosis of patients with colorectal cancer (CRC) is assessed through conventional clinicopathological parameters, which are not always accurate. Members of the human kallikrein-related peptidases gene family represent potential cancer biomarkers. The aim of this study was to investigate the expression of human tissue kallikrein-related peptidase 10 (KLK10) by immunohistochemistry in CRC, to correlate this expression with various histopathological and clinical variables, and to evaluate its significance as a predictor of disease outcome. KLK10 expression was evaluated by immunohistochemistry and a combined expression score was calculated for each case based on intensity and percentage of positivity. A statistically significant positive association was observed between KLK10 and tumor stage and liver metastases (p = 0.015 and p = 0.035, respectively). Paradoxically, a negative association was observed between KLK10 and tumor grade (p = 0.009). Kaplan-Meier survival curves and univariate analysis showed that both KLK10 expression and stage had statistically significant correlations with disease-free survival (DFS) (p = 0.030 and p < 0.001, respectively) and overall survival (p = 0.010 and p = 0.001, respectively). Cox multivariate analysis showed that both KLK10 expression and stage were independent predictors of unfavorable DFS (p = 0.057 and p = 0.001, respectively) and overall survival (p = 0.009 and p = 0.001, respectively). In conclusion, KLK10 immunostaining is an independent prognostic marker in patients with CRC.

Proteomic signatures of the desmoplastic invasion front reveal collagen type XII as a marker of myofibroblastic differentiation during colorectal cancer metastasis.

Cancer-associated fibroblasts (CAFs), represent a pivotal compartment of solid cancers (desmoplasia), and are causatively implicated in cancer development and progression. CAFs are recruited by growth factors secreted by cancer cells and they present a myofibroblastic phenotype, similar to the one obtained by resident fibroblasts during wound healing. Paracrine signaling between cancer cells and CAFs results in a unique protein expression profile in areas of desmoplastic reaction, which is speculated to drive metastasis. In an attempt to decipher large-scale proteomic profiles of the cancer invasive margins, we developed an in vitro coculture model system, based on tumor-host cell interactions between colon cancer cells and CAFs. Proteomic analysis of conditioned media derived from these cocultures coupled to mass spectrometry and bioinformatic analysis was performed to uncover myofibroblastic signatures of the cancer invasion front. Our analysis resulted in the identification and generation of a desmoplastic protein dataset (DPD), consisting of 152 candidate proteins of desmoplasia. By using monoculture exclusion datasets, a secretome algorithm and gene-expression meta-analysis in DPD, we specified a 22-protein "myofibroblastic signature" with putative importance in the regulation of colorectal cancer metastasis. Of these proteins, we investigated collagen type XII by immunohistochemistry, a fibril-associated collagen with interrupted triple helices (FACIT), whose expression has not been reported in desmoplastic lesions in any type of cancer. Collagen type XII was highly expressed in desmoplastic stroma by and around alpha-smooth muscle actin (α-SMA) positive CAFs, as well as in cancer cells lining the invasion front, in a small cohort of colon cancer patients. Other stromal markers, such as collagen type III, were also expressed in stromal collagen, but not in cancer cells. In a complementary fashion, gene expression meta-analysis revealed that COL12A1 is also an upregulated gene in colorectal cancer. Our proteomic analysis identified previously documented markers of tumor invasion fronts and our DPD could serve as a pool for future investigation of the tumor microenvironment. Collagen type XII is a novel candidate marker of myofibroblasts, and/or cancer cells undergoing dedifferentiation.