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1.
PLoS Biol ; 14(11): e1002581, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27880766

ABSTRACT

Although cancers are considered stem cell diseases, mechanisms involving stem cell alterations are poorly understood. Squamous cell carcinoma (SQCC) is the second most common lung cancer, and its pathogenesis appears to hinge on changes in the stem cell behavior of basal cells in the bronchial airways. Basal cells are normally quiescent and differentiate into mucociliary epithelia. Smoking triggers a hyperproliferative response resulting in progressive premalignant epithelial changes ranging from squamous metaplasia to dysplasia. These changes can regress naturally, even with chronic smoking. However, for unknown reasons, dysplasias have higher progression rates than earlier stages. We used primary human tracheobronchial basal cells to investigate how copy number gains in SOX2 and PIK3CA at 3q26-28, which co-occur in dysplasia and are observed in 94% of SQCCs, may promote progression. We find that SOX2 cooperates with PI3K signaling, which is activated by smoking, to initiate the squamous injury response in basal cells. This response involves SOX9 repression, and, accordingly, SOX2 and PI3K signaling levels are high during dysplasia, while SOX9 is not expressed. By contrast, during regeneration of mucociliary epithelia, PI3K signaling is low and basal cells transiently enter a SOX2LoSOX9Hi state, with SOX9 promoting proliferation and preventing squamous differentiation. Transient reduction in SOX2 is necessary for ciliogenesis, although SOX2 expression later rises and drives mucinous differentiation, as SOX9 levels decline. Frequent coamplification of SOX2 and PIK3CA in dysplasia may, thus, promote progression by locking basal cells in a SOX2HiSOX9Lo state with active PI3K signaling, which sustains the squamous injury response while precluding normal mucociliary differentiation. Surprisingly, we find that, although later in invasive carcinoma SOX9 is generally expressed at low levels, its expression is higher in a subset of SQCCs with less squamous identity and worse clinical outcome. We propose that early pathogenesis of most SQCCs involves stabilization of the squamous injury state in stem cells through copy number gains at 3q, with the pro-proliferative activity of SOX9 possibly being exploited in a subset of SQCCs in later stages.


Subject(s)
Carcinoma, Squamous Cell/pathology , Lung Neoplasms/pathology , Neoplastic Stem Cells/pathology , SOXB1 Transcription Factors/physiology , Animals , Cell Differentiation , Humans , Lung Neoplasms/enzymology , Lung Neoplasms/metabolism , Mice , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , Trachea/pathology
2.
Histopathology ; 64(6): 826-39, 2014 May.
Article in English | MEDLINE | ID: mdl-24251405

ABSTRACT

AIMS: We investigated the sensitivity and specificity of two novel Epidermal growth factor receptor (EGFR) mutation-specific antibodies in the detection of the most common EGFR mutations in lung adenocarcinoma. METHODS AND RESULTS: A total of 241 resected lung adenocarcinoma specimens and six resected post-neoadjuvant gefitinib adenocarcinomas were analysed for EGFR mutation using mass spectrometry, fragment analysis and direct PCR sequencing platforms. Tissue arrays and/or full sections of these cases were evaluated using immunohistochemistry with two novel antibodies (clones SP125 and SP111) and two previously reported antibodies (clones 43B2 and 6B6), specific for L858R or 15-nucleotide exon-19 deletion EGFR mutations. SP125 antibody detected EGFR L858R mutation with a sensitivity of 76% and positive predictive value of 73%. SP111 antibody stained the 15-nucleotide EGFR exon-19 deletions with a sensitivity of 83% and a positive predictive value of 94%. Pretreatment with gefitinib did not affect antibody performance. Full-section immunohistochemical staining detected heterogeneous mutant EGFR proteins expression in tumours, and revealed L858R mutation in the non-neoplastic bronchial epithelium adjacent to EGFR L858R-carrying carcinomas in three of 16 (19%) cases. CONCLUSIONS: Immunohistochemistry using EGFR mutant-specific antibodies may be useful in shortening the diagnostic time of lung adenocarcinoma with most common EGFR mutations, especially in samples with low tumour cellularity.


Subject(s)
Adenocarcinoma/metabolism , ErbB Receptors/metabolism , Lung Neoplasms/metabolism , Mutation , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Antibodies , ErbB Receptors/genetics , Female , Humans , Immunohistochemistry/methods , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Male , Middle Aged , Sensitivity and Specificity
3.
Proc Natl Acad Sci U S A ; 108(17): 7160-5, 2011 Apr 26.
Article in English | MEDLINE | ID: mdl-21474781

ABSTRACT

The tumor microenvironment strongly influences cancer development, progression, and metastasis. The role of carcinoma-associated fibroblasts (CAFs) in these processes and their clinical impact has not been studied systematically in non-small cell lung carcinoma (NSCLC). We established primary cultures of CAFs and matched normal fibroblasts (NFs) from 15 resected NSCLC. We demonstrate that CAFs have greater ability than NFs to enhance the tumorigenicity of lung cancer cell lines. Microarray gene-expression analysis of the 15 matched CAF and NF cell lines identified 46 differentially expressed genes, encoding for proteins that are significantly enriched for extracellular proteins regulated by the TGF-ß signaling pathway. We have identified a subset of 11 genes (13 probe sets) that formed a prognostic gene-expression signature, which was validated in multiple independent NSCLC microarray datasets. Functional annotation using protein-protein interaction analyses of these and published cancer stroma-associated gene-expression changes revealed prominent involvement of the focal adhesion and MAPK signaling pathways. Fourteen (30%) of the 46 genes also were differentially expressed in laser-capture-microdissected corresponding primary tumor stroma compared with the matched normal lung. Six of these 14 genes could be induced by TGF-ß1 in NF. The results establish the prognostic impact of CAF-associated gene-expression changes in NSCLC patients.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Fibroblasts/metabolism , Gene Expression Regulation, Neoplastic , Lung Neoplasms/metabolism , Neoplasm Proteins/biosynthesis , Animals , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Transformed , Disease-Free Survival , Female , Fibroblasts/pathology , Gene Expression Profiling , Humans , Lung/metabolism , Lung/pathology , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Mice , Mice, SCID , Oligonucleotide Array Sequence Analysis , Signal Transduction , Survival Rate
4.
Lab Invest ; 93(4): 397-407, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23399854

ABSTRACT

There are very few xenograft models available for the study of esophageal (E) and gastro-esophageal junction (GEJ) cancer. Using a NOD/SCID model, we implanted 90 primary E and GEJ tumors resected from patients and six endoscopic biopsy specimens. Of 69 resected tumors with histologically confirmed viable adenocarcinoma or squamous cell carcinoma, 22 (32%) was engrafted. One of 11 tumors, considered to have had a complete pathological response to neo-adjuvant chemo-radiation, also engrafted. Of the 23 patients whose tumors were engrafted, 65% were male; 30% were early stage while 70% were late stage; 22% received neo-adjuvant chemo-radiation; 61% were GEJ cancers. Engraftment occurred in 18/54 (33%) adenocarcinomas and 5/16 (31%) squamous cell carcinomas. Small endoscopic biopsy tissue had a 50% (3/6) engraftment rate. Of the factors analyzed, pretreatment with chemo-radiation and well/moderate differentiation showed significantly lower correlation with engraftment (P<0.05). In the subset of patients who did not receive neo-adjuvant chemo-radiation, 18/41 (44%) engrafted compared with those with pretreatment where 5/29 (17%, P=0.02) engrafted. Primary xenograft lines may be continued through 4-12 passages. Xenografts maintained similar histology and morphological characteristics with only minor variations even after multiple passaging in most instances.


Subject(s)
Adenocarcinoma/pathology , Carcinoma, Squamous Cell/pathology , Esophageal Neoplasms/pathology , Neoplasms, Experimental/pathology , Xenograft Model Antitumor Assays , Adult , Aged , Aged, 80 and over , Animals , Female , Graft Survival , Humans , Male , Mice , Mice, Inbred NOD , Mice, SCID , Middle Aged , Neoplasm Transplantation
5.
Mod Pathol ; 23(3): 434-8, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20062007

ABSTRACT

The distinction between dermatofibroma, particularly cellular variant, and dermatofibrosarcoma protuberans in excisional biopsies is usually straightforward. However, a separation between the two may be sometimes challenging, especially in superficial biopsies. Although factor XIIIa and CD34 immunostains are useful in differentiating dermatofibroma and dermatofibrosarcoma protuberans in most instances, focal CD34 positivity may be seen in cellular fibrous histiocytoma. Some cases reveal overlapping immunostain results. D2-40 identifies a 40-kDa O-linked sialoglycoprotein present on a variety of tissues including testicular germ cell tumors as well as lymphatic endothelium. In this study, we investigated the utility of D2-40 in separating dermatofibroma from dermatofibrosarcoma protuberans and compared the results with other commonly used immunostains. Fifty-six cases of dermatofibroma (including six cellular variant) and 29 cases of dermatofibrosarcoma protuberans were retrieved from the archives of Department of Anatomic Pathology at Sunnybrook Health Sciences Center in University of Toronto. We applied factor XIIIa, CD34, and monoclonal mouse anti-D2-40 immunostains to formalin-fixed, paraffin-embedded tissue sections. All 56 (100%) cases of dermatofibroma demonstrated strong and diffuse immunoreactivity to D2-40 in the spindle cells and stroma. Similarly, factor XIIIa showed strong and diffuse positivity in the spindle cells. Nearly all dermatofibromas were negative for CD34 except one case revealing focal positivity. None of dermatofibrosarcoma protuberans cases were labeled by D2-40, although four cases showed weak and patchy background staining in contrary to diffuse, strong, and crisp staining seen in dermatofibromas. Our results indicate that D2-40 seems to be a sensitive immunohistochemical marker for dermatofibromas, including cellular variant. Focal and faint D2-40 staining may be seen in the stroma of dermatofibrosarcoma protuberans. Our findings suggest that D2-40 can be used as a complementary immunostain to factor XIIIa and CD34 in problematic and challenging cases on superficial biopsies.


Subject(s)
Antibodies, Monoclonal/analysis , Biomarkers, Tumor/analysis , Dermatofibrosarcoma/diagnosis , Histiocytoma, Benign Fibrous/diagnosis , Animals , Antibodies, Monoclonal, Murine-Derived , Antigens, CD34/analysis , Dermatofibrosarcoma/chemistry , Diagnosis, Differential , Factor XIIIa/analysis , Histiocytoma, Benign Fibrous/chemistry , Humans , Immunohistochemistry , Mice , Stromal Cells/chemistry , Stromal Cells/pathology
6.
J Cutan Pathol ; 37(9): 953-7, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20175823

ABSTRACT

BACKGROUND: Proper diagnosis of myeloid leukemia cutis (LC) is of great clinical importance but can be difficult because no single immunohistochemical marker is adequately sensitive or specific for definitive diagnosis. Thus, a broader panel of markers is often desirable. CD163 is highly specific for normal and neoplastic cells of the monocyte/histiocyte lineage. In this study, we examined the value of CD163 in the diagnosis of acute myeloid LC. METHODS: A total of 34 cases, including 18 cases of myelomonocytic or monocytic LC, 10 cases of myeloid LC without monocytic component and 6 cases of acute lymphoblastic leukemia/lymphoma (ALL), were stained with CD163. RESULTS: CD163 was expressed in 8 of 18 (44%) of myelomonocytic or monocytic LC and 1 of 10 (10%) of other myeloid LC, but in none of the ALL cases (0/6). CD163 was highly specific (90%) for myeloid LC with a monocytic component, but showed low sensitivity in the diagnosis of both myeloid LC in general (24%) and myeloid LC with a monocytic component (44%). CONCLUSIONS: Our results suggest that CD163 has utility as a specific marker for myeloid LC in conjunction with currently used immunohistochemical stains, but should not be used alone for diagnosis.


Subject(s)
Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , Leukemia, Myeloid, Acute/metabolism , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Receptors, Cell Surface/metabolism , Skin Neoplasms/metabolism , Biomarkers, Tumor/metabolism , Humans , Immunoenzyme Techniques , Monocytes/pathology , Predictive Value of Tests , Retrospective Studies , Skin/pathology
7.
PLoS One ; 10(3): e0121872, 2015.
Article in English | MEDLINE | ID: mdl-25826681

ABSTRACT

The high morbidity and mortality of patients with esophageal (E) and gastro-esophageal junction (GEJ) cancers, warrants new pre-clinical models for drug testing. The utility of primary tumor xenografts (PTXGs) as pre-clinical models was assessed. Clinicopathological, immunohistochemical markers (p53, p16, Ki-67, Her-2/neu and EGFR), and global mRNA abundance profiles were evaluated to determine selection biases of samples implanted or engrafted, compared with the underlying population. Nine primary E/GEJ adenocarcinoma xenograft lines were further characterized for the spectrum and stability of gene/protein expression over passages. Seven primary esophageal adenocarcinoma xenograft lines were treated with individual or combination chemotherapy. Tumors that were implanted (n=55) in NOD/SCID mice had features suggestive of more aggressive biology than tumors that were never implanted (n=32). Of those implanted, 21/55 engrafted; engraftment was associated with poorly differentiated tumors (p=0.04) and older patients (p=0.01). Expression of immunohistochemical markers were similar between patient sample and corresponding xenograft. mRNA differences observed between patient tumors and first passage xenografts were largely due to loss of human stroma in xenografts. mRNA patterns of early vs late passage xenografts and of small vs large tumors of the same passage were similar. Complete resistance was present in 2/7 xenografts while the remaining tumors showed varying degrees of sensitivity, that remained constant across passages. Because of their ability to recapitulate primary tumor characteristics during engraftment and across serial passaging, PTXGs can be useful clinical systems for assessment of drug sensitivity of human E/GEJ cancers.


Subject(s)
Esophageal Neoplasms/drug therapy , Esophagogastric Junction/pathology , Stomach Neoplasms/drug therapy , Animals , Esophageal Neoplasms/pathology , Humans , Mice , Mice, Inbred NOD , Mice, SCID , Stomach Neoplasms/pathology , Xenograft Model Antitumor Assays
8.
Acta Radiol Short Rep ; 3(8): 2047981614549497, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25346853

ABSTRACT

A 34-year-old man found a mildly tender preauricular mass. Ultrasonography revealed an anechoic mass in the superficial lobe of the parotid gland. Magnetic resonance imaging showed thin ring-like contrast enhancement and homogenously high intensity on T2-weighted images. The mass was resected due to its rapid growth. The cystic lesion contained keratine-like material and a stratified squamous epithelium without granular layers, which was consistent with keratocystoma.

9.
J Clin Pathol ; 66(8): 644-8, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23526597

ABSTRACT

Malignant melanoma is one of the most aggressive malignancies in humans and is responsible for 60-80% of deaths from skin cancers. The 5-year survival of patients with metastatic malignant melanoma is about 14%. Its incidence has been increasing in the white population over the past two decades. The mechanisms leading to malignant transformation of melanocytes and melanocytic lesions are poorly understood. In developing malignant melanoma, there is a complex interaction of environmental and endogenous (genetic) factors, including: dysregulation of cell proliferation, programmed cell death (apoptosis) and cell-to-cell interactions. The understanding of genetic alterations in signalling pathways of primary and metastatic malignant melanoma and their interactions may lead to therapeutics modalities, including targeted therapies, particularly in advanced melanomas that have high mortality rates and are often resistant to chemotherapy and radiotherapy. Our knowledge regarding the molecular biology of malignant melanoma has been expanding. Even though several genes involved in melanocyte development may also be associated with melanoma cell development, it is still unclear how a normal melanocyte becomes a melanoma cell. This article reviews the molecular events and recent findings associated with malignant melanoma.


Subject(s)
Melanocytes/metabolism , Melanoma/metabolism , Animals , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Gene-Environment Interaction , Humans , Melanocytes/cytology , Melanoma/genetics , Melanoma/pathology , Mutation , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , Risk Factors
10.
J Clin Oncol ; 31(17): 2173-81, 2013 Jun 10.
Article in English | MEDLINE | ID: mdl-23630215

ABSTRACT

PURPOSE: We undertook this analysis of KRAS mutation in four trials of adjuvant chemotherapy (ACT) versus observation (OBS) to clarify the prognostic/predictive roles of KRAS in non-small-cell lung cancer (NSCLC). METHODS: KRAS mutation was determined in blinded fashion. Exploratory analyses were performed to characterize relationships between mutation status and subtype and survival outcomes using a multivariable Cox model. RESULTS: Among 1,543 patients (763 OBS, 780 ACT), 300 had KRAS mutations (codon 12, n = 275; codon 13, n = 24; codon 14, n = 1). In OBS patients, there was no prognostic difference for overall survival for codon-12 (mutation v wild type [WT] hazard ratio [HR] = 1.04; 95% CI, 0.77 to 1.40) or codon-13 (HR = 1.01; 95% CI, 0.47 to 2.17) mutations. No significant benefit from ACT was observed for WT-KRAS (ACT v OBS HR = 0.89; 95% CI, 0.76 to 1.04; P = .15) or codon-12 mutations (HR = 0.95; 95% CI, 0.67 to 1.35; P = .77); with codon-13 mutations, ACT was deleterious (HR = 5.78; 95% CI, 2.06 to 16.2; P < .001; interaction P = .002). There was no prognostic effect for specific codon-12 amino acid substitution. The effect of ACT was variable among patients with codon-12 mutations: G12A or G12R (HR = 0.66; P = .48), G12C or G12V (HR = 0.94; P = .77) and G12D or G12S (HR = 1.39; P = .48; comparison of four HRs, including WT, interaction P = .76). OBS patients with KRAS-mutated tumors were more likely to develop second primary cancers (HR = 2.76, 95% CI, 1.34 to 5.70; P = .005) but not ACT patients (HR = 0.66; 95% CI, 0.25 to 1.75; P = .40; interaction, P = .02). CONCLUSION: KRAS mutation status is not significantly prognostic. The potential interaction in patients with codon-13 mutations requires validation. At this time, KRAS status cannot be recommended to select patients with NSCLC for ACT.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Genes, ras , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Mutation , Aged , Carcinoma, Non-Small-Cell Lung/pathology , Chemotherapy, Adjuvant , Female , Gene Pool , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Prognosis , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins p21(ras) , Randomized Controlled Trials as Topic , Survival Analysis , Treatment Outcome , ras Proteins/genetics
11.
Clin Cancer Res ; 18(7): 1914-24, 2012 Apr 01.
Article in English | MEDLINE | ID: mdl-22307136

ABSTRACT

PURPOSE: Non-small cell lung cancer (NSCLC) is a highly metastatic cancer with limited treatment options, thus requiring development of novel targeted therapies. Our group previously identified L1 cell adhesion molecule (L1CAM) expression as a member of a prognostic multigene expression signature for NSCLC patients. However, there is little information on the biologic function of L1CAM in lung cancer cells. This study investigates the functional and prognostic role of L1CAM in NSCLC. EXPERIMENTAL DESIGN: Cox proportional hazards regression analysis was done on four independent published mRNA expression datasets of primary NSCLCs. L1CAM expression was suppressed by short-hairpin RNA (shRNA)-mediated silencing in human NSCLC cell lines. Effects were assessed by examining in vitro migration and invasion, in vivo tumorigenicity in mice, and metastatic potential using an orthotopic xenograft rat model of lung cancer. RESULTS: L1CAM is an independent prognostic marker in resected NSCLC patients, with overexpression strongly associated with worse prognosis. L1CAM downregulation significantly decreased cell motility and invasiveness in lung cancer cells and reduced tumor formation and growth in mice. Cells with L1CAM downregulation were deficient in constitutive extracellular signal-regulated kinase (Erk) activation. Orthotopic studies showed that L1CAM suppression in highly metastatic lung cancer cells significantly decreases spread to distant organs, including bone and kidney. CONCLUSION: L1CAM is a novel prometastatic gene in NSCLC, and its downregulation may effectively suppress NSCLC tumor growth and metastasis. Targeted inhibition of L1CAM may be a novel therapy for NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Lung Neoplasms/metabolism , Neoplasms, Experimental/metabolism , Neural Cell Adhesion Molecule L1/metabolism , Aged , Animals , Blotting, Western , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Movement , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Male , Mice , Mice, SCID , Middle Aged , Neoplasm Metastasis , Neoplasms, Experimental/genetics , Neoplasms, Experimental/pathology , Neural Cell Adhesion Molecule L1/genetics , Phosphorylation , Prognosis , RNA Interference , Rats , Rats, Nude , Reverse Transcriptase Polymerase Chain Reaction , Transplantation, Heterologous
12.
PLoS One ; 7(7): e41102, 2012.
Article in English | MEDLINE | ID: mdl-22829912

ABSTRACT

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) induces apoptosis in a variety of cancer cell lines with little or no effect on normal cells. However, its effect is limited as some cancers including pancreatic cancer show de novo resistance to TRAIL induced apoptosis. In this study we report that GSK-3 inhibition using the pharmacologic agent AR-18, enhanced TRAIL sensitivity in a range of pancreatic and prostate cancer cell lines. This sensitization was found to be caspase-dependent, and both pharmacological and genetic knock-down of GSK-3 isoforms resulted in apoptotic features as shown by cleavage of PARP and caspase-3. Elevated levels of reactive oxygen intermediates and disturbance of mitochondrial membrane potential point to a mitochondrial amplification loop for TRAIL-induced apoptosis after GSK-3 inhibition. Consistent with this, overexpression of anti-apoptotic mitochondrial targets such as Bcl-XL, Mcl-1, and Bcl-2 rescued PANC-1 and PPC-1 cells from TRAIL sensitization. However, overexpression of the caspase-8 inhibitor CrmA also inhibited the sensitizing effects of GSK-3 inhibitor, suggesting an additional role for GSK-3 that inhibits death receptor signaling. Acute treatment of mice bearing PANC-1 xenografts with a combination of AR-18 and TRAIL also resulted in a significant increase in apoptosis, as measured by caspase-3 cleavage. Sensitization to TRAIL occurred despite an increase in ß-catenin due to GSK-3 inhibition, suggesting that the approach might be effective even in cancers with dysregulated ß-catenin. These results suggest that GSK-3 inhibitors might be effectively combined with TRAIL for the treatment of pancreatic cancer.


Subject(s)
Apoptosis/drug effects , Glycogen Synthase Kinase 3/antagonists & inhibitors , Glycogen Synthase Kinase 3/metabolism , Pancreatic Neoplasms/metabolism , TNF-Related Apoptosis-Inducing Ligand/pharmacology , Apoptosis/genetics , Cell Line, Tumor , Enzyme Inhibitors/pharmacology , Humans , Male , Membrane Potential, Mitochondrial/drug effects , Myeloid Cell Leukemia Sequence 1 Protein , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , bcl-X Protein/genetics , bcl-X Protein/metabolism
13.
PLoS One ; 7(10): e46677, 2012.
Article in English | MEDLINE | ID: mdl-23056397

ABSTRACT

Lipocalin 2 (LCN2) is a small secreted protein and its elevated expression has been observed in pancreatic as well as other cancer types. LCN2 has been reported to promote resistance to drug-induced apoptosis, enhance invasion through its physical association with matrix metalloproteinase-9, and promote in vivo tumor growth. LCN2 was found to be commonly expressed in patient PDAC samples and its pattern of immunohistochemical staining intensified with increasing severity in high-grade precursor lesions. Downregulation of LCN2 in two pancreatic ductal adenocarcinoma cell lines (BxPC3 and HPAF-II) with high LCN2 expression significantly reduced attachment, invasion, and tumour growth in vivo, but not proliferation or motility. Downregulation of LCN2 in two pancreatic ductal adenocarcinoma cell lines (BxPC3 and HPAF-II) with high expression significantly reduced attachment, invasion, and tumour growth in vivo. In contrast, LCN2 overexpression in PANC1, with low endogenous expression, significantly increased invasion, attachment, and enhanced tumor growth. Suppression of LCN2 in BxPC3 and HPAF-II cells increased their sensitivity to gemcitabine in vitro, and in vivo when BxPC3 was tested. Furthermore, LCN2 promotes expression of VEGF and HIF1A which contribute to enhanced vascularity. These overall results demonstrate that LCN2 plays an important role in the malignant progression of pancreatic ductal carcinoma and is a potential therapeutic target for this disease.


Subject(s)
Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/metabolism , Deoxycytidine/analogs & derivatives , Lipocalins/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/metabolism , Animals , Carcinoma, Pancreatic Ductal/genetics , Cell Line, Tumor , Deoxycytidine/pharmacology , Deoxycytidine/therapeutic use , Drug Resistance, Neoplasm/genetics , Humans , Immunohistochemistry , In Vitro Techniques , Mice , Pancreatic Neoplasms/genetics , Gemcitabine
14.
Article in English | MEDLINE | ID: mdl-20936153

ABSTRACT

Malignant melanoma is one of the most aggressive malignancies in human and is responsible for almost 60% of lethal skin tumors. Its incidence has been increasing in white population in the past two decades. There is a complex interaction of environmental (exogenous) and endogenous, including genetic, risk factors in developing malignant melanoma. 8-12% of familial melanomas occur in a familial setting related to mutation of the CDKN2A gene that encodes p16. The aim of this is to briefly review the microanatomy and physiology of the melanocytes, epidemiology, risk factors, clinical presentation, historical classification and histopathology and, more in details, the most recent discoveries in biology and genetics of malignant melanoma. At the end, the final version of 2009 AJCC malignant melanoma staging and classification is presented.

15.
J Med Chem ; 52(2): 358-68, 2009 Jan 22.
Article in English | MEDLINE | ID: mdl-19093877

ABSTRACT

Fibroblast activation protein (FAP) is a cell-surface serine protease highly expressed on cancer-associated fibroblasts of human epithelial carcinomas but not on normal fibroblasts, normal tissues, and cancer cells. We report herein a novel FAP-triggered photodynamic molecular beacon (FAP-PPB) comprising a fluorescent photosensitizer and a black hole quencher 3 linked by a peptide sequence (TSGPNQEQK) specific to FAP. FAP-PPB was effectively cleaved by both human FAP and murine FAP. By use of the HEK293 transfected cells (HEK-mFAP, FAP(+); HEK-vector, FAP(-)), systematic in vitro and in vivo experiments validated the FAP-specific activation of FAP-PPB in cancer cells and mouse xenografts, respectively. FAP-PPB was cleaved by FAP, allowing fluorescence restoration in FAP-expressing cells while leaving non-expressing FAP cells undetectable. Moreover, FAP-PPB showed FAP-specific photocytotoxicity toward HEK-mFAP cells whereas it was non-cytotoxic toward HEK-Vector cells. This study suggests that the FAP-PPB is a potentially useful tool for epithelial cancer detection and treatment.


Subject(s)
Antigens, Neoplasm/physiology , Biomarkers, Tumor/physiology , Neoplasms, Glandular and Epithelial/diagnosis , Neoplasms, Glandular and Epithelial/drug therapy , Photochemotherapy , Serine Endopeptidases/physiology , Animals , Blotting, Western , Cell Line , Chromatography, High Pressure Liquid , Endopeptidases , Fibroblasts/cytology , Flow Cytometry , Gelatinases , Humans , Immunohistochemistry , Membrane Proteins , Mice , Microscopy, Confocal , Neoplasms, Glandular and Epithelial/pathology
16.
Neoplasia ; 11(12): 1292-300, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20019837

ABSTRACT

Complete resection of early-stage non-small cell lung cancer (NSCLC) is potentially curative, yet approximately 50% of patients are at risk for developing metastatic recurrence. Met, the receptor for hepatocyte growth factor (HGF) is a receptor tyrosine kinase with demonstrated roles in regulating cellular proliferation, motility, morphogenesis, and apoptosis. Met receptor and its ligand, HGF, are commonly overexpressed in NSCLC, and their overexpression has been associated with poor prognosis, which could potentially involve a paracrine and/or autocrine activation loop. However, there is as yet no direct evidence that HGF-Met signaling directly promotes metastasis in NSCLC cells. Using retroviral transduction, we overexpressed the human c-met and hgf complementary DNA, alone or in combination in the NCI-H460 human large cell carcinoma cell line. The HGF/Met co-overexpressing (H460-HGF/Met) cells demonstrated enhanced tumorigenicity in xenograft SCID mice. When these cells are implanted orthotopically into the lungs of nude rats, only the H460-HGF/Met cells showed higher spontaneous metastases to distant organs including bone, brain, and kidney. These results provide evidence that autocrine overactivation of the Met- HGF loop enhances systemic metastases in NSCLC. Targeted interference of this loop may potentially be an effective adjuvant therapy to improve survival of early-stage NSCLC patients.


Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Hepatocyte Growth Factor/metabolism , Lung Neoplasms/pathology , Proto-Oncogene Proteins c-met/metabolism , Receptors, Growth Factor/metabolism , Animals , Bone Neoplasms/genetics , Bone Neoplasms/metabolism , Bone Neoplasms/secondary , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/secondary , Carcinoma, Large Cell/genetics , Carcinoma, Large Cell/metabolism , Carcinoma, Large Cell/pathology , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic , Hepatocyte Growth Factor/genetics , Humans , Immunohistochemistry , Kidney Neoplasms/genetics , Kidney Neoplasms/metabolism , Kidney Neoplasms/secondary , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Male , Mice , Mice, SCID , Neoplasms, Experimental/genetics , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Proto-Oncogene Proteins c-met/genetics , Rats , Rats, Nude , Receptors, Growth Factor/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transfection , Transplantation, Heterologous
17.
J Low Genit Tract Dis ; 11(4): 284-9, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17917577

ABSTRACT

BACKGROUND: Blue nevi are rare in the cervix and vagina. Melanocytes are not normally found in these sites and have been hypothesized to arise either from the Schwann cells of stromal nerves or from melanocytic precursors which have aberrantly migrated from the neural crest to rest in the Müllerian stroma. Because of their rarity (3 previous cases in the literature), vaginal blue nevi have not previously been studied with immunohistochemical and ultrastructural analysis. DESIGN: We describe 3 cases of blue nevus occurring in the Müllerian tract, 1 in the vagina and 2 in the endocervix. RESULTS: The vaginal lesion was seen during routine examination of a 40-year-old woman. The endocervical blue nevi were incidental findings in hysterectomies performed for leiomyomata and endometrial serous carcinoma in women aged 44 and 57 years, respectively. All 3 cases showed loose aggregates of cytologically benign, pigmented, dendritic spindle cells in the superficial stroma. They were immunoreactive for S100 and melan-A, but not HMB45. Ultrastructural analysis revealed numerous melanosomes, with no Schwannian features identified. Compared with the endocervical lesions, the vaginal nevus cells were more heavily pigmented, and on electron microscopy, a greater proportion of stage IV melanosomes were seen. CONCLUSIONS: We provide the first immunohistochemical and ultrastructural findings in a vaginal blue nevus, which confirm that it is of a similar nature to the endocervical blue nevi. Ultrastructurally, our results support a melanocytic rather than Schwannian origin for Müllerian blue nevi.


Subject(s)
Nevus, Blue/pathology , Uterine Cervical Neoplasms/pathology , Vaginal Neoplasms/pathology , Adult , Female , Humans , Immunohistochemistry , Middle Aged , Nevus, Blue/metabolism , Nevus, Blue/ultrastructure , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/ultrastructure , Vaginal Neoplasms/metabolism , Vaginal Neoplasms/ultrastructure
18.
J Cutan Pathol ; 32(5): 360-5, 2005 May.
Article in English | MEDLINE | ID: mdl-15811122

ABSTRACT

We report a 48-year-old man who presented with ulcerated plaques and nodules of the lower extremities. Skin biopsies revealed a dense lymphocytic infiltrate involving the dermis and the subcutis in a lobular and septal pattern. No overt cytological atypia was present. Notably, several features resembling lupus erythematosus were present, including vacuolar interface change and abundant dermal mucin deposition. The patient developed pulmonary nodules, and a lung biopsy showed a perivascular and interstitial lymphoid infiltrate without overt atypia. The cutaneous and pulmonary lymphoid infiltrates showed similar immunohistochemical profiles: CD3(+) CD4(-) CD8(+/-) CD56(+). Monoclonal rearrangements of the T-cell receptor gamma gene with similar migration patterns were identified from both locations. The patient developed fatal hemophagocytic syndrome, involving liver, spleen, lymph nodes, and bone marrow. This case is one amongst the rare reports of subcutaneous panniculitis-like T-cell lymphoma with systemic involvement.


Subject(s)
Dermis/metabolism , Lupus Erythematosus, Systemic/diagnosis , Lymphoma, T-Cell/diagnosis , Lymphoma, T-Cell/metabolism , Mucins/metabolism , Panniculitis/pathology , Subcutaneous Tissue/pathology , Diagnosis, Differential , Fatal Outcome , Humans , Leg Ulcer/pathology , Lymphoma, T-Cell/pathology , Male , Middle Aged , T-Lymphocytes, Cytotoxic/pathology
19.
Arch Pathol Lab Med ; 129(2): 215-8, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15679424

ABSTRACT

CONTEXT: Localized laryngeal amyloidosis is an uncommon condition with limited long-term follow-up studies. The precise etiology and pathogenesis are not entirely clear. OBJECTIVE: To further characterize the histopathologic features and possible pathogenesis of localized laryngeal amyloidosis. DESIGN: Three cases of primary localized laryngeal amyloidosis were identified at our institutions from 1980 to 2003. The clinical features and histologic and immunohistochemical patterns were evaluated. Systemic workups were pursued during the long-term follow-up. RESULTS: The common presentation of the patients was hoarseness. The lesions involved vocal cords, anterior commissure, and ventricle. Microscopically, the amyloid was present within the submucosa with an adjacent lymphoplasmacytic infiltrate. The plasma cells and amyloid demonstrated monoclonal light chain restriction in all 3 cases (2 lambda, 1 kappa). No evidence of systemic amyloidosis or an overt B-cell lymphoma was found in these patients. Two patients with long-term follow-up underwent subsequent surgical removals for multiple recurrences, which occurred within 1 year of the initial diagnosis. CONCLUSIONS: The demonstration of monoclonal light chain expression in the plasmacytic infiltrate and amyloid component in the absence of systemic lymphomas indicates that localized laryngeal amyloidosis may represent a form of benign monoclonal plasma cell dyscrasia. A close follow-up of the patients may be indicated for early detection of recurrences.


Subject(s)
Amyloidosis/diagnosis , Laryngeal Diseases/diagnosis , Time , Adult , Follow-Up Studies , Humans , Male , Middle Aged
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