Establishment of an experimental human lung adenocarcinoma cell line SPC-A-1BM with high bone metastases potency by (99m)Tc-MDP bone scintigraphy. Nucl Med Biol. 2009;36:313-321. [PMID: 19324277 DOI: 10.1016/j.nucmedbio.2008.12.007]

Apoptotic signaling pathways in bone metastatic lung cancer: a comprehensive analysis

This review provides a comprehensive analysis of apoptotic signaling pathways in the context of bone metastatic lung cancer, emphasizing the intricate molecular mechanisms and microenvironmental influences. Beginning with an overview of apoptosis in cancer, the paper explores the specific molecular characteristics of bone metastatic lung cancer, highlighting alterations in apoptotic pathways. Focused discussions delve into key apoptotic signaling pathways, including the intrinsic and extrinsic pathways, and the roles of critical molecular players such as Bcl-2 family proteins and caspases. Microenvironmental factors, such as the tumor microenvironment, extracellular matrix interactions, and immune cell involvement, are examined in depth. The review also addresses experimental approaches and techniques employed in studying apoptotic signaling, paving the way for a discussion on current therapeutic strategies, their limitations, and future prospects. This synthesis contributes a holistic understanding of apoptosis in bone metastatic lung cancer, offering insights for potential therapeutic advancements.

Screening for oncogenic AF1q expression predicts disease recurrence in gastric cancer patients

AF1q associates with tumor progression and metastases upon WNT signaling. The downstream WNT target CD44 has demonstrated prognostic significance in gastric cancer (GC). This study evaluates the impact of AF1q on tumor stage and survival in GC patients. Immunohistochemical marker expression was analyzed and data were processed to correlation and survival analysis. Out of 182 GC samples, 178 (97.8%) showed moderate to high AF1q expression (p < 0.001), these samples correlated with positive lymph node stage (p = 0.036). In a subgroup analysis of patients with nodal-positive GC (n = 129, 70.9%), enhanced tumoral AF1q expression resulted in impaired recurrence-free survival (RFS, p = 0.030). Enhanced tumoral CD44 expression resulted in impaired disease-specific survival (DSS) in the subgroup of patients with nodal-positive GC (p = 0.031) as well as in the overall GC group (p = 0.005). AF1q demonstrated as an independent prognostic marker for RFS (p = 0.035) and CD44 for DSS (p = 0.036). AF1q has shown potential for prognostication of RFS in GC patients and is predominantly expressed in nodal-positive GC. Testing AF1q provides a possibility of identifying patients with locoregional (and advanced) disease, particularly at risk for disease recurrence. Implementing AF1q into the diagnostic process may facilitate screening, prognosis estimation as well as consideration of preoperative multimodal treatment in patients qualifying for elective upfront surgery.

Non-small cell lung cancer cell-derived exosomal miR-17-5p promotes osteoclast differentiation by targeting PTEN

Aberrant activity of bone resorbing osteoclasts plays a key role in the development of osteoporosis and cancer bone metastasis. The identification of novel and specific targets will be helpful for the development of new therapeutic strategies for bone metastasis in lung cancer. Herein, we examined microRNAs in tumor cell-derived exosomes to investigate the communication between the bone environment and tumor cells. TCGA database analysis showed that the level of miR-17-5p increased in non-small cell lung cancer tissues compared with non-tumor tissues. To investigate the function of exosomes in inducing osteoclastogenesis, osteoclast precursors were incubated with exosomes isolated from non-small cell lung cancer cell line, as well as receptor activator of NF-KB ligand and M-CSF to induce osteoclastogenesis. We found that exosomal miR-17-5p is upregulated in a non-small cell lung cancer cell line with bone metastasis compared with the original cell line. Overexpression of miR-17-5p enhanced the osteoclastogenesis of RAW264.7 cells. PTEN was identified as a direct target of miR-17-5p and showed negative effects on osteoclastogenesis. Importantly, treatment of LY294002 (an inhibitor of the PI3K/Akt pathway) attenuated miR-17-5p-mediated osteoclastogenesis effects. Taken together, our findings demonstrated that miR-17-5p promotes osteoclastogenesis through the PI3K/Akt pathway via targeting PTEN in lung cancer.

Preclinical SPECT and SPECT-CT in Oncology

Molecular imaging enables both spatial and temporal understanding of the complex biologic systems underlying carcinogenesis and malignant spread. Single-photon emission tomography (SPECT) is a versatile nuclear imaging-based technique with ideal properties to study these processes in vivo in small animal models, as well as to identify potential drug candidates and characterize their antitumor action and potential adverse effects. Small animal SPECT and SPECT-CT (single-photon emission tomography combined with computer tomography) systems continue to evolve, as do the numerous SPECT radiopharmaceutical agents, allowing unprecedented sensitivity and quantitative molecular imaging capabilities. Several of these advances, their specific applications in oncology as well as new areas of exploration are highlighted in this chapter.

Effects of Sorafenib and Arsenic Trioxide on U937 and KG-1 Cell Lines: Apoptosis or Autophagy?

Objective

Acute myeloid leukemia (AML) is a clonal disorder of hemopoietic progenitor cells. The Raf serine/threonine (Ser/Thr) protein kinase isoforms including B-Raf and RAF1, are the upstream in the MAPK cascade that play essential functions in regulating cellular proliferation and survival. Activated autophagy-related genes have a dual role in both cell death and cell survival in cancer cells. The cytotoxic activities of arsenic trioxide (ATO) were widely assessed in many cancers. Sorafenib is known as a multikinase inhibitor which acts through suppression of Ser/Thr kinase Raf that was reported to have a key role in tumor cell signaling, proliferation, and angiogenesis. In this study, we examined the combination effect of ATO and sorafenib in AML cell lines.

Materials and Methods

In this experimental study, we studied in vitro effects of ATO and sorafenib on human leukemia cell lines. The effective concentrations of compounds were determined by MTT assay in both single and combination treatments. Apoptosis was evaluated by annexin-V FITC staining. Finally, mRNA levels of apoptotic and autophagy genes were evaluated using real-time polymerase chain reaction (PCR).

Results

Data demonstrated that sorafenib, ATO, and their combination significantly increase the number of apoptotic cells. We found that the combination of ATO and sorafenib significantly reduces the viability of U937 and KG-1 cells. The expression level of selective autophagy genes, ULK1 and Beclin1 decreased but LC3-II increased in U937.

Conclusion

The expression levels of apoptotic and autophagy activator genes were increased in response to treatment. The crosstalk between apoptosis and autophagy is a complicated mechanism and further investigations seem to be necessary.

The Oncogene AF1Q is Associated with WNT and STAT Signaling and Offers a Novel Independent Prognostic Marker in Patients with Resectable Esophageal Cancer

AF1q impairs survival in hematologic and solid malignancies. AF1q expression is associated with tumor progression, migration, and chemoresistance, and acts as a transcriptional co-activator in WNT and STAT signaling. This study evaluates the role of AF1q in patients with resectable esophageal cancer (EC). A total of 278 patients operated on for esophageal cancer were retrospectively included, and the expression of AF1q, CD44, and pYSTAT3 was analyzed following immunostaining. Quantified data were processed to correlational and survival analysis. In EC patients, an elevated expression of AF1q was associated with CD44 (p = 0.004), and pYSTAT3 (p = 0.0002). High AF1q expression in primary tumors showed high AF1q expression in the corresponding lymph nodes (p= 0.016). AF1q expression was higher after neoadjuvant therapy (p= 0.0002). Patients with AF1q-positive EC relapsed and died earlier compared to patients with AF1q-negative EC (disease-free survival (DFS), p= 0.0005; disease-specific survival (DSS), p= 0.003); in the multivariable Cox regression model, AF1q proved to be an independent prognostic marker (DFS, p= 0.01; DSS, p= 0.03). AF1q is associated with WNT and STAT signaling; it impairs and independently predicts DFS and DSS in patients with resectable EC. The testing of AF1q could facilitate prognosis estimation and provide a possibility of identifying the patients responsive to the therapeutic blockade of its oncogenic downstream targets.

A slow-cycling subpopulation of melanoma cells with highly invasive properties

Melanoma is a heterogeneous tumor with different subpopulations showing different proliferation rates. Slow-cycling cells were previously identified in melanoma, but not fully biologically characterized. Using the label-retention method, we identified a subpopulation of slow-cycling cells, defined as label-retaining cells (LRC), with strong invasive properties. We demonstrate through live imaging that LRC are leaving the primary tumor mass at a very early stage and disseminate to peripheral organs. Through global proteome analyses, we identified the secreted protein SerpinE2/protease nexin-1 as causative for the highly invasive potential of LRC in melanomas.

MLLT11/AF1q boosts oncogenic STAT3 activity through Src-PDGFR tyrosine kinase signaling

Constitutive STAT3 activation by tyrosine phosphorylation of mutated or amplified tyrosine kinases (pYSTAT3) is critical for cancer initiation, progression, invasion, and motility of carcinoma cells. We showed that AF1q is associated with STAT3 signaling in breast cancer cells. In xenograft models, enhanced AF1q expression activated STAT3 and promoted tumor growth and metastasis in immunodeficient NSG mice. The cytokine secretory phenotype of MDA-MB-231LN breast cancer cells with altered AF1q expression revealed changes in expression of platelet-derived growth factor subunit B (PDGF-B). AF1q-induced PDGF-B stimulated motility, migration, and invasion of MDA-MB-231LN cells, and AF1q up-regulated platelet-derived growth factor receptor (PDGFR) signaling. Further, AF1q-induced PDGFR signaling enhanced STAT3 activity through Src kinase activation, which could be blocked by the Src kinase inhibitor PP1. Moreover, AF1q up-regulated tyrosine kinase signaling through PDGFR signaling, which was blockable by imatinib. In conclusion, we demonstrated that enhanced AF1q expression contributes to persistent and oncogenic pYSTAT3 levels in invasive carcinoma cells by activating Src kinase through activation of the PDGF-B/PDGFR cascade. Therefore, AF1q plays an essential role as a cofactor in PDGF-B-driven STAT3 signaling.

Anti-Vascular Endothelial Growth Factor Targeting by Curcumin and Thalidomide in Acute Myeloid Leukemia Cells

Acute myeloid leukemias (AMLs) are blood disorders that exhibit uncontrolled growth and reduction of apoptosis rates. As with other malignancies, progression may be result of induction and formation of new blood vessels influenced by disease conditions. Cancer cells produce a variety of factors which play important roles in angiogenesis. Vascular endothelial growth factor (VEGF) is critical for many malignancies, including AMLs. Curcumin, as a natural compound, is able to enhance apoptosis via a mechanism affecting regulatory genes. As a new strategy we here evaluated anti-VEGF properties of curcumin, alone and in combination with thalidomide, in leukemic cell lines. Growth inhibitory effects were assessed by MTT assay and apoptosis was detected by annexin/PI staining in U937 and KG-1 cell lines. mRNA expression levels of VEGF isoforms were evaluated by qRT-PCR. Curcumin inhibited proliferation and induced apoptosis in both KG-1 and U937 cells and this effect was stronger in combination with thalidomide. In KG-1 cells, the level of VEGF (A, B, C and D) mRNA was decreased in curcumin-treated as compared to untreated cells. Maximum effects were obtained at the concentration of 40 μM curcumin in U937 cells. Taken together, the results indicate that the VEGF autocrine loop may have an impact on AML development and progression and could be considered as a therapeutic target. Thalidomide as a VEGF inhibitor in combination with curcumin appears to have a synergistic impact on inhibition of cell proliferation and promotion of apoptosis.

AF1q Mediates Tumor Progression in Colorectal Cancer by Regulating AKT Signaling

The up-regulation of ALL1-fused gene from chromosome 1q (AF1q) is commonly seen in aggressive hematologic malignancies as well as in several solid tumor tissues. However, its expression and intrinsic function in human colorectal cancer (CRC) remains largely undefined. To explore the role of AF1q in human CRC progression, AF1q expression was analyzed in human CRC tissue samples and CRC cell lines. Clinical specimens revealed that AF1q was up-regulated in human CRC tissues, and that this up-regulation was associated with tumor metastasis and late tumor, lymph node, metastasis (TNM) stage. AF1q knockdown by shRNA inhibited tumor cell proliferation, migration, invasion, and epithelial-mesenchymal transition in vitro, as well as tumorigenesis and liver metastasis in vivo, whereas these effects were reversed following AF1q overexpression. These AF1q-mediated effects were modulated by the protein kinase B (AKT) signaling pathway, and inhibition of AKT signaling attenuated AF1q-induced tumor promotion. Thus, AF1q contributes to CRC tumorigenesis and progression through the activation of the AKT signaling pathway. AF1q might therefore serve as a promising new target in the treatment of CRC.

AF1q is a novel TCF7 co-factor which activates CD44 and promotes breast cancer metastasis

AF1q is an MLL fusion partner that was identified from acute myeloid leukemia (AML) patients with t (1; 11) (q21; q23) chromosomal abnormality. The function of AF1q is not yet fully known, however, elevated AF1q expression is associated with poor clinical outcomes in various malignancies. Here, we show that AF1q specifically binds to T-cell-factor-7 (TCF7) in the Wnt signaling pathway and results in transcriptional activation of CD44 as well as multiple downstream targets of the TCF7/LEF1. In addition, enhanced AF1q expression promotes breast cancer cell proliferation, migration, mammosphere formation, and chemo-resistance. In xenograft models, enforced AF1q expression in breast cancer cells also promotes liver metastasis and lung colonization. In a cohort of 63 breast cancer patients, higher percentages of AF1q-positive cancer cells in primary sites were associated with significantly poorer overall survival (OS), disease-free survival (DFS), and brain metastasis-free survival (b-MFS). Using paired primary/metastatic samples from the same patients, we demonstrate that AF1q-positive breast cancer cells become dynamically dominant in the metastatic sites compared to the primary sites. Our findings indicate that breast cancer cells with a hyperactive AF1q/TCF7/CD44 regulatory axis in the primary sites may represent "metastatic founder cells" which have invasive properties.

Animal Models of Bone Metastasis

Bone is one of the most common sites of cancer metastasis in humans and is a significant source of morbidity and mortality. Bone metastases are considered incurable and result in pain, pathologic fracture, and decreased quality of life. Animal models of skeletal metastases are essential to improve the understanding of the molecular pathways of cancer metastasis and growth in bone and to develop new therapies to inhibit and prevent bone metastases. The ideal animal model should be clinically relevant, reproducible, and representative of human disease. Currently, an ideal model does not exist; however, understanding the strengths and weaknesses of the available models will lead to proper study design and successful cancer research. This review provides an overview of the current in vivo animal models used in the study of skeletal metastases or local tumor invasion into bone and focuses on mammary and prostate cancer, lymphoma, multiple myeloma, head and neck squamous cell carcinoma, and miscellaneous tumors that metastasize to bone.

Everolimus and zoledronic acid--a potential synergistic treatment for lung adenocarcinoma bone metastasis

Non-small-cell lung cancer (NSCLC) frequently metastasizes to bone. It is known that zoledronic acid is cytostatic to tumors, and everolimus, the inhibitor for mammalian target of the rapamycin, could inhibit many types of cancer. Herein, we evaluated the effect of zoledronic acid alone and in combination with everolimus on treating lung adenocarcinoma bone metastasis in vitro and in vivo. Mice treated with zoledronic acid in combination with everolimus had more apoptotic lung cancer cells and more cells were arrested in the G1/G0 phase. The phosphorylation of p70S6K was inhibited in the combination treatment group. Lung cancer cell invasion was also significantly inhibited in the group with combination treatment in vitro. Bone nuclear scans revealed more metastatic lesions in controls compared with those in the combination treatment group. Bone scans and radiographic images indicated that combination therapy significantly reduced bone metastasis. The moderate survival rate suggested that the drug combination was synergistic, which can delay NSCLC bone metastasis and prolong survival in vivo.

Establishment and characterization of a singaporean chinese lung adenocarcinoma cell line with four copies of the epidermal growth factor receptor gene

We have established a lung adenocarcinoma cell line, ETCC016, from lung pleural effusion of a male Singaporean Chinese with advanced lung adenocarcinoma. The subject smoked 20 cigarettes per day for more than 30 years. The cell line arose from spontaneous transformation of cells grown in a collagen-coated culture dish. Transformed characteristics of the cell line include the ability to reach high confluency in a culture dish, low cell doubling time, ability to form colonies in soft agar, and ability to form solid tumor in immune-compromised SCID mice. Immunostaining showed that the cells originated from lung epithelial cells. Genomic analysis revealed a large amount of chromosomal aberrations (gain and loss of genetic materials, and loss of heterozygosity [LOH]), indicative of a long history of smoking. The cells have four copies of epidermal growth factor receptor (EGFR) and three copies of MYC, but have lost one copy of the RB1 gene. LOH was detected in TP53 and BRAF genes. There is no anaplastic lymphoma kinase (ALK) gene rearrangement. The ETCC016 lung adenocarcinoma cell line has demonstrated susceptibility towards inhibitors specific for EGFR/HER2 and ALK targets, but resistance to MYC-specific inhibitor. This cell line will be a useful model for further understanding of lung adenocarcinoma.

Colony-stimulating factor 1 potentiates lung cancer bone metastasis

Colony-stimulating factor 1 (CSF1) is essential for osteoclastogenesis that mediates osteolysis in metastatic tumors. Patients with lung cancer have increased CSF1 in serum and high levels are associated with poor survival. Adenocarcinomas metastasize rapidly and many patients suffer from bone metastasis. Lung cancer stem-like cells sustain tumor growth and potentiate metastasis. The purpose of this study was to determine the role of CSF1 in lung cancer bone metastasis and whether inhibition of CSF1 ameliorates the disease. Human lung adenocarcinoma A549 cells were examined in vitro for CSF1/CSF1R. A549-luc cells were injected intracardiac in NOD/SCID mice and metastasis was assessed. To determine the effect of CSF1 knockdown (KD) in A549 cells on bone metastasis, cells were stably transfected with a retroviral vector containing short-hairpin CSF1 (KD) or empty vector (CT). Results showed that A549 cells express CSF1/CSF1R; CSF1 increased their proliferation and invasion, whereas soluble CSF1R inhibited invasion. Mice injected with A549-luc cells showed osteolytic bone lesions 3.5 weeks after injection and lesions increased over 5 weeks. Tumors recapitulated adenocarcinoma morphology and showed osteoclasts along the tumor/bone interface, trabecular, and cortical bone loss. Analyses of KD cells showed decreased CSF1 protein levels, reduced colony formation in soft agar assay, and decreased fraction of stem-like cells. In CSF1KD mice, the incidence of tumor metastasis was similar to controls, although fewer CSF1KD mice had metastasis in both hind limbs. KD tumors showed reduced CSF1 expression, Ki-67+ cells, and osteoclasts. Importantly, there was a low incidence of large tumors >0.1 mm(2) in CSF1KD mice compared with control mice (10% vs 62.5%). This study established a lung osteolytic bone metastasis model that resembles human disease and suggests that CSF1 is a key determinant of cancer stem cell survival and tumor growth. Results may lead to novel strategies to inhibit CSF1 in lung cancer and improve management of bone metastasis.

Development and validation of a highly sensitive urine-based test to identify patients with colonic adenomatous polyps

Objectives:

Adenomatous polyps are precursors of colorectal cancer; their detection and removal is the goal of colon cancer screening programs. However, fecal-based methods identify patients with adenomatous polyps with low levels of sensitivity. The aim or this study was to develop a highly accurate, prototypic, proof-of-concept, spot urine-based diagnostic test using metabolomic technology to distinguish persons with adenomatous polyps from those without polyps.

Methods:

Prospective urine and stool samples were collected from 876 participants undergoing colonoscopy examination in a colon cancer screening program, from April 2008 to October 2009 at the University of Alberta. Colonoscopy reference standard identified 633 participants with no colonic polyps and 243 with colonic adenomatous polyps. One-dimensional nuclear magnetic resonance spectra of urine metabolites were analyzed to define a diagnostic metabolomic profile for colonic adenomas. A urine metabolomic diagnostic test for colonic adenomatous polyps was established using 67% of the samples (un-blinded training set) and validated using the other 33% of the samples (blinded testing set). The urine metabolomic diagnostic test's specificity and sensitivity were compared with those of fecal-based tests.

Results:

Using a two-component, orthogonal, partial least-squares model of the metabolomic profile, the un-blinded training set identified patients with colonic adenomatous polyps with 88.9% sensitivity and 50.2% specificity. Validation using the blinded testing set confirmed sensitivity and specificity values of 82.7% and 51.2%, respectively. Sensitivities of fecal-based tests to identify colonic adenomas ranged from 2.5 to 11.9%.

Conclusions:

We describe a proof-of-concept spot urine-based metabolomic diagnostic test that identifies patients with colonic adenomatous polyps with a greater level of sensitivity (83%) than fecal-based tests.

Novel esophageal squamous cell carcinoma bone metastatic clone isolated by scintigraphy, X ray and micro PET/CT

AIM: To establish a Chinese esophageal squamous cell carcinoma (ESCC) cell line with high bone metastasis potency using ^99mTc-methylene diphosphonate (^99mTc-MDP) micro-pinhole scintigraphy, X ray and micro-positron emission tomography/computed tomography (PET/CT) for exploring the mechanism of occurrence and development in esophageal cancer.

METHODS: The cells came from a BALB/c nu/nu immunodeficient mouse, and oncogenic tumor tissue was from a surgical specimen from a 61-year-old male patient with ESCC. The cell growth curve was mapped and analysis of chromosome karyotype was performed. Approximately 1 × 10⁶ oncogenic cells were injected into the left cardiac ventricle of immunodeficient mice. The bone metastatic lesions of tumor-bearing mice were detected by ^99mTc-MDP scintigraphy, micro-PET/CT and X-ray, and were resected from the mice under deep anesthesia. The bone metastatic cells in the lesions were used for culture and for repeated intracardiac inoculation. This in vivo/in vitro experimental metastasis study was repeated for four cycles. All of the suspicious bone sites were confirmed by pathology. Real-time polymerase chain reaction was used to compare the gene expression in the parental cells and in the bone metastatic clone.

RESULTS: The surgical specimen was implanted subcutaneously in immunodeficient mice and the tumorigenesis rate was 100%. First-passage oncogenic cells were named CEK-Sq-1. The chromosome karyotype analysis of the cell line was hypotriploid. The bone metastasis rate went from 20% with the first-passage oncogenic cells via intracardiac inoculation to 90% after four cycles. The established bone metastasis clone named CEK-Sq-1BM had a high potential to metastasize in bone, including mandible, humerus, thoracic and lumbar vertebrae, scapula and femur. The bone metastasis lesions were successfully detected by micro-pinhole bone scintigraphy, micro-PET/CT, and X-ray. The sensitivity, specificity and accuracy of the micro-pinhole scintigraphy, X-ray, and micro-PET/CT imaging examinations were: 89.66%/32%/80%, 88.2%/100%/89.2%, and 88.75%/77.5%/87.5%, respectively. Some gene expression difference was found between parental and bone metastasis cells.

CONCLUSION: This newly established Chinese ESCC cell line and animal model may provide a useful tool for the study of the pathogenesis and development of esophageal carcinoma.

Psoralen inhibits bone metastasis of breast cancer in mice

Breast cancer is the most common female malignancy and it frequently metastasizes to bone. Metastatic breast cancer continues to be the primary cause of death for women in East and Southeast Asia. Psoralen is a furocoumarin that can be isolated from the seeds of Psoralea corylifolia L. Psoralen exhibits a wide range of biological properties and has been demonstrated as an antioxidant, antidepressant, anticancer, antibacterial, and antiviral agent. Additionally, it is involved in the formation and regulation of bone. This study investigated whether psoralen can inhibit metastasis of breast cancer to bone in vivo. Histological, molecular biological, and imaging analyses revealed that psoralen inhibits bone metastases in mice. Psoralen may function to inhibit breast cancer cell growth in the bone microenvironment and regulate the function of osteoblasts and osteoclasts in tumor-bearing mice. The results of this study suggest that psoralen is a bone-modifying agent and a potential therapeutic to treat patients with bone metastases.

Genes regulated in metastatic osteosarcoma: evaluation by microarray analysis in four human and two mouse cell line systems

Osteosarcoma (OS) is a rare bone neoplasm that affects mainly adolescents. It is associated with poor prognosis in case of metastases formation. The search for metastasis predicting markers is therefore imperative to optimize treatment strategies for patients at risk and important for the search of new drugs for the treatment of this devastating disease. Here, we have analyzed by microarray the differential gene expression in four human and two mouse OS cell line systems consisting of parental cell lines with low metastatic potential and derivatives thereof with increased metastatic potential. Using two osteoblastic cell line systems, the most common OS phenotype, we have identified forty-eight common genes that are differentially expressed in metastatic cell lines compared to parental cells. The identified subset of metastasis relevant genes in osteoblastic OS overlapped only minimally with differentially expressed genes in the other four preosteoblast or nonosteoblastic cell line systems. The results imply an OS phenotype specific expression pattern of metastasis regulating proteins and form a basis for further investigation of gene expression profiles in patients' samples combined with survival analysis with the aim to optimize treatment strategies to develop new drugs and to consequently improve the survival of patients with the most common form of osteoblastic OS.

[Establishment of a novel chinese human lung adenocarcinoma cell line CPA-Yang3 and its real bone metastasis clone CPA-Yang3BM in immunodeficient mice]

BACKGROUND AND OBJECTIVE

The recurrence and metastasis of lung cancer is a tough problem worldwide. The aim of this study is to establish a novel Chinese lung adenocarcinoma cell line and its real bone-seeking clone sub-line for exploring the molecular mechanism of lung cancer metastasis.

METHODS

The cells came from the pleural effusion of a sixty-five years old female patient with lung adenocarcinoma and supraclavicular lymph node metastases. The gene expression was detected by real-time quantitative PCR. Intracardiac injection of the cells into nude mice was performed and in vivo imaging was obtained by bone scintigraphy and conventional radiography. Bone metastases were determined on bone scintigraphy and then the lesions were resected under deep anesthesia for bone metastasis cancer cell culture. The process was repeated for four cycles to obtain a real bone-seeking clone.

RESULTS

The tumorigenesis rate started at 4th passage in immunodeficient mice via subcutaneously and as well as later passages. Approximately 1×10⁶ cancer cells were injected into left cardiac ventricle of immunodeficient mice resulted bone metastasis sites were successfully revealed by bone scintigraphy and pathological diagnosis, the mandible (100%), scapula (33%), humerus (50%), vertebral column (50%), femur (66.7%) and accompanied invasion with other organs, the adrenal gland (17%), pulmonary (33%), liver (50%), submaxillary gland (33%) in the mice after inoculation two-three weeks. The chromosome karyotype analysis of the cells was subdiploid. Quantitative real-time PCR was used to examined and compared with SPC-A-1 lung adenocarcinoma, ESM1, VEGF-C, IL-6, IL-8, AR, SVIL, FN1 genes were overexpress. The novel cell was named CPA-Yang3. The femur metastasis cell was repeated in vivo-in vitro-in vivo with three cycles and harvested a real bone metastasis clone. It was named CPA-Yang3BM.

CONCLUSIONS

Tne characteristics of novel strain CPAYang3 is a highly metastasis cell line of Chinese lung adenocarcinoma and CPA-Yang3BM is a real bone-seeking clone.

The serine protease inhibitor serpinE2 is a novel target of ERK signaling involved in human colorectal tumorigenesis

BACKGROUND

Among the most harmful of all genetic abnormalities that appear in colorectal cancer (CRC) development are mutations of KRAS and its downstream effector BRAF as they result in abnormal extracellular signal-related kinase (ERK) signaling. In a previous report, we had shown that expression of a constitutive active mutant of MEK1 (caMEK) in normal rat intestinal epithelial cells (IECs) induced morphological transformation associated with epithelial to mesenchymal transition, growth in soft agar, invasion and metastases in nude mice. Results from microarrays comparing control to caMEK-expressing IECs identified the gene encoding for serpinE2, a serine protease inhibitor, as a potential target of activated MEK1.

RESULTS

1- RT-PCR and western blot analyses confirmed the strong up-regulation of serpinE2 expression and secretion by IECs expressing oncogenic MEK, Ras or BRAF. 2- Interestingly, serpinE2 mRNA and protein were also markedly enhanced in human CRC cells exhibiting mutation in KRAS and BRAF. 3- RNAi directed against serpinE2 in caMEK-transformed rat IECs or in human CRC cell lines HCT116 and LoVo markedly decreased foci formation, anchorage-independent growth in soft agarose, cell migration and tumor formation in nude mice. 4- Treatment of CRC cell lines with U0126 markedly reduced serpinE2 mRNA levels, indicating that expression of serpinE2 is likely dependent of ERK activity. 5- Finally, Q-PCR analyses demonstrated that mRNA levels of serpinE2 were markedly increased in human adenomas in comparison to healthy adjacent tissues and in colorectal tumors, regardless of tumor stage and grade.

CONCLUSIONS

Our data indicate that serpinE2 is up-regulated by oncogenic activation of Ras, BRAF and MEK1 and contributes to pro-neoplastic actions of ERK signaling in intestinal epithelial cells. Hence, serpinE2 may be a potential therapeutic target for colorectal cancer treatment.