Development of a rational strategy for integration of lactate dehydrogenase A suppression into therapeutic algorithms for head and neck cancer.

Background: Lactate dehydrogenase (LDH) is a critical metabolic enzyme. LDH A (LDHA) overexpression is a hallmark of aggressive malignancies and has been linked to tumour initiation, reprogramming and progression in multiple tumour types. However, successful LDHA inhibition strategies have not materialised in the translational and clinical space.

Regulation of receptor tyrosine kinases by miRNA: overexpression of miRNA using lentiviral inducible expression vectors.

MicroRNAs have the ability to alter and regulate multiple genes, including RTK family members, making them an attractive approach for molecular therapeutic development. We use a pCDNA6.2-EmGFP-microRNA expression vector to overexpress individual mature microRNA and then transfer the expression cassette into a single, inducible lentiviral vector (pINDUCER20).

Dysregulated expression of FOXM1 isoforms drives progression of pancreatic cancer.

The transcription factor Forkhead box M1 (FOXM1) plays important roles in oncogenesis. However, the expression statuses of FOXM1 isoforms and their impact on and molecular basis in oncogenesis are unknown. We sought to determine the identities of FOXM1 isoforms in and the impact of their expression on pancreatic cancer development and progression using human tissues, cell lines, and animal models.

The critical role of dysregulated FOXM1-PLAUR signaling in human colon cancer progression and metastasis.

Purpose: The mammalian Forkhead Box (Fox) transcription factor FOXM1 is implicated in tumorigenesis including mouse intestinal cancer. However, the clinical significance of FOXM1 signaling in human colorectal cancer pathogenesis remains unknown.

Experimental Design: We investigated FOXM1 expression in 203 cases of primary colon cancer and matched normal colon tissue specimens and explored the underlying mechanisms of altered FOXM1 expression and the impact of this altered expression on colon cancer growth and metastasis using in vitro and animal models of colon cancer.

Dysregulated Krüppel-like factor 4 and vitamin D receptor signaling contribute to progression of hepatocellular carcinoma.

Background & Aims: Krüppel-like factor 4 (KLF4) is a transcription factor and putative tumor suppressor. However, little is known about its effects in hepatocellular carcinogenesis. We investigated the clinical significance, biologic effects, and mechanisms of dysregulated KLF4 signaling.

A novel FoxM1-caveolin signaling pathway promotes pancreatic cancer invasion and metastasis.

Caveolin-1 (Cav-1), a principal structural component of caveolar membrane domains, contributes to cancer development but its precise functional roles and regulation remain unclear. In this study, we determined the oncogenic function of Cav-1 in preclinical models of pancreatic cancer and in human tissue specimens. Cav-1 expression levels correlated with metastatic potential and epithelial-mesenchymal transition (EMT) in both mouse and human pancreatic cancer cells.

Disruption of Klf4 in villin-positive gastric progenitor cells promotes formation and progression of tumors of the antrum in mice.

Background & Aims: Krüppel-like factor 4 (Klf4) is a putative gastric tumor suppressor gene. Rare, villin-positive progenitor cells in the gastric antrum have multilineage potential. We investigated the function of Klf4 in these cells and in gastric carcinogenesis.

Combining betulinic acid and mithramycin a effectively suppresses pancreatic cancer by inhibiting proliferation, invasion, and angiogenesis.

Both betulinic acid (BA) and mithramycin A (MIT) exhibit potent antitumor activity through distinct mechanisms of Sp1 inhibition. However, it is unknown whether a combination of these two compounds results in a synergistic inhibitory effect on pancreatic cancer growth and/or has a therapeutic advantage over gemcitabine. In xenograft mouse models of human pancreatic cancer, treatment with either BA or MIT alone showed dose-dependent antitumor activity but led to systemic side effects as measured by overall weight loss.

KLF4-mediated negative regulation of IFITM3 expression plays a critical role in colon cancer pathogenesis.

Purpose: IFITM3, an IFN-inducible gene, is overexpressed in human colorectal cancer. In this study, we sought to determine the clinical significance and underlying mechanisms of its dysregulated expression in human colon tumor specimens and murine models of this disease.

Experimental Design: IFITM3 expression in a tissue microarray of tumor and matched normal colon tissue specimens and lymph node metastasis specimens obtained from 203 patients with colon cancer was measured immunohistochemically.

KLF4α up-regulation promotes cell cycle progression and reduces survival time of patients with pancreatic cancer.

Background & Aims: Krüppel-like factor 4 (KLF4) is a transcription factor associated with tumor suppression and oncogenesis. KLF4 suppresses pancreatic tumorigenesis by unknown mechanisms; we investigated alterations that might affect KLF4 function and lead to tumor formation.

Methods: We identified different isoforms of KLF4 in pancreatic cancer cells by reverse-transcriptase polymerase chain reaction, cloning, and DNA sequence analyses.

Combined treatment of pancreatic cancer with mithramycin A and tolfenamic acid promotes Sp1 degradation and synergistic antitumor activity.

Mithramycin (MIT) and tolfenamic acid (TA) inhibit the activity of the transcription factor Sp1. In the present study, we investigated whether pancreatic cancer treatment with a combination of these compounds has a synergistic effect on Sp1 activity, tumor growth, and their underlying response mechanisms. Treatment of pancreatic tumor xenografts with MIT and TA produced dose-dependent antitumor activity, and significant antitumor activity of either compound alone was directly associated with systemic side effects.

Modeling liver metastasis using a tumor cell line derived from an enhanced green fluorescent protein transgenic mouse.

The liver is a common repository for metastases, second only to lymph nodes. The majority of gastrointestinal cancer deaths are attributed to liver metastasis. Researchers have widely used stable transfection of green florescent protein (GFP) to track tumor cells in the liver metastasis cascade.

Critical role and regulation of transcription factor FoxM1 in human gastric cancer angiogenesis and progression.

The mammalian forkhead box (Fox) transcription factor FoxM1b is implicated in tumorigenesis. However, the presence of expression and role of FoxM1b in gastric cancer remain unknown. Therefore, we investigated FoxM1b expression in 86 cases of primary gastric cancer and 57 normal gastric tissue specimens.

Inhibition of the growth and metastasis of human colon cancer by restoration of RUNX3 expression in cancer cells.

Recent studies demonstrated an epigenetic inactivation of the runt-related transcription factor 3 (RUNX3) gene in human colon cancer. However, it remains unclear whether RUNX3 is tumor suppressive in colon cancer and, if so, the underlying molecular mechanisms of this activity are still unknown. In the present study, we sought to determine the level of RUNX3 expression in human colon tumor specimens and used an animal model of colon cancer to determine the impact of RUNX3 expression on tumor growth and metastasis.

Kruppel-like factor 4 induces p27Kip1 expression in and suppresses the growth and metastasis of human pancreatic cancer cells.

The zinc finger transcription factor Krüppel-like factor 4 (KLF4) has been implicated in both tumor suppression and progression. However, its function in pancreatic cancer has not been well characterized. Here, we show that pancreatic cancer cell lines expressed various levels of KLF4 RNA and protein.

Gene-expression profiling in Chinese patients with colon cancer by coupling experimental and bioinformatic genomewide gene-expression analyses: identification and validation of IFITM3 as a biomarker of early colon carcinogenesis.

Background: Expression microarrays are widely used for investigating the nature and extent of global gene-expression changes in human cancer. Accurate genomewide gene-expression profiles have not been conducted in colon tumor and normal colon tissue specimens obtained from Chinese patients.

Methods: In the present study a pure population of colon cancer and normal colon cells was obtained and the global gene-expression differences were compared in the 2 cell types using combined experimental and bioinformatic approaches.

Therapeutic inhibition of Sp1 expression in growing tumors by mithramycin a correlates directly with potent antiangiogenic effects on human pancreatic cancer.

Background: Human pancreatic cancer over expresses the transcription factor Sp1. However, the role of Sp1 in pancreatic cancer angiogenesis and its use as target for antiangiogenic therapy remain unexplored.

Methods: Archived human pancreatic cancer specimens were used to assess gene expression and microvessel density (MVD) status by immunohistochemistry: Small-interfering RNA (siRNA) was used to determine the impact of altered Sp1 expression on tumor growth and angiogenesis, and mithramycin A (MIT) was used to evaluate Sp1-targeted antiangiogenic treatment of human pancreatic cancer in animal models.

Molecular basis of the synergistic antiangiogenic activity of bevacizumab and mithramycin A.

The impact of antiangiogenic therapy on the Sp1/vascular endothelial growth factor (VEGF) pathway and that of alteration of Sp1 signaling on the efficacy of antiangiogenic therapy is unclear, yet understanding their interactions has significant clinical implications. Treatment with bevacizumab, a neutralizing antibody against VEGF, suppressed human pancreatic cancer growth in nude mice. Gene expression analyses revealed that this treatment substantially up-regulated the expression of Sp1 and its downstream target genes, including VEGF and epidermal growth factor receptor, in tumor tissues, whereas it did not have this effect on pancreatic cancer cells in culture.

Loss of Krüppel-like factor 4 expression contributes to Sp1 overexpression and human gastric cancer development and progression.

Purpose: Increasing evidence indicates that the transcription factor, Sp1, regulates the expression of multiple genes involved in tumor development and progression. We have recently reported that Sp1 overexpression is directly correlated with the angiogenic potential of and poor prognosis for human gastric cancer. However, the underlying mechanisms that result in Sp1 overexpression remain unclear.

RUNX3 inhibits the expression of vascular endothelial growth factor and reduces the angiogenesis, growth, and metastasis of human gastric cancer.

Purpose: Recent studies indicated that RUNX3 exhibits potent antitumor activity. However, the underlying molecular mechanisms of this activity remain unclear. In the present study, we used a gastric cancer model to determine the effect of RUNX3 expression on tumor angiogenesis.

A high expression level of insulin-like growth factor I receptor is associated with increased expression of transcription factor Sp1 and regional lymph node metastasis of human gastric cancer.

Insulin-like growth factor I receptor (IGF-IR) is critical to cell survival and growth and altered IGF-IR expression is found in many human cancers. However, its expression and potential role in gastric cancer development and progression has not been explored. The IGF-IR expression level was determined via immunohistochemistry in primary tumor and lymph node metastasis of 86 cases of resected gastric cancer.

Nitric oxide synthase II suppresses the growth and metastasis of human cancer regardless of its up-regulation of protumor factors.

Inducible nitric oxide (NO) synthase (NOS) II has been implicated in macrophage-mediated antitumor activity. However, use of the NOS II gene in cancer therapy is problematic because of the double-edged nature of NO action. Herein we show that adenoviral vectors mediated effective NOS II gene transfer into various human tumors.

Loss of RUNX3 expression significantly affects the clinical outcome of gastric cancer patients and its restoration causes drastic suppression of tumor growth and metastasis.

Identification of precise prognostic marker and effective therapeutic target is pivotal in the treatment of gastric cancer. In the present study, we determined the level of RUNX3 expression in gastric cancer cells and gastric cancer specimens and the impact of its alteration on cancer biology and clinical outcome. There was a loss or substantial decrease of RUNX3 protein expression in 86 cases of gastric tumors as compared with that in normal gastric mucosa (P < 0.

Transcription factor Sp1 expression is a significant predictor of survival in human gastric cancer.

The transcription factor Sp1 regulates the expression of multiple genes. However, its expression and role in human tumor development and progression remain unclear. Using immunohistochemistry, we investigated Sp1 expression patterns in 86 cases of human gastric cancer having various clinicopathologic characteristics, 57 normal gastric tissue specimens, and 53 lymph node metastases.

Direct demonstration of negative regulation of tumor growth and metastasis by host-inducible nitric oxide synthase.

Inducible nitric oxide synthase (NOS) II expression can be induced in the tumor bed, predominantly in host cells that infiltrate and surround a tumor. However, the impact of this physiological NOS II expression in host cells on tumor growth and metastasis remains unclear because of a lack of appropriate experimental approaches. In the present study, three NOS II-null (NOS II(-/-)) tumor cell lines, KX-dw1, KX-dw4, and KX-dw7, were established and verified using Southern, Northern, and Western blot analysis, and nitric oxide production assays.