Type Homeobox Transcription Factor Research Articles

The potential role of SNHG16/ miRNA-146a/ TRAF6 signaling pathway in the protective effect of zoledronate against colorectal cancer and associated osteoporosis in mouse model

Bone fracture as a consequence of colorectal cancer (CRC) and associated osteoporosis (OP) is considered a risk factor for increasing the mortality rate among CRC patients. SNHG16/ miRNA-146a/ TRAF6 signaling pathway is a substantial contributor to neoplastic evolution, progression, and metastasis. Here, we investigated the effect of zoledronate (ZOL) on the growth of CRC and associated OP in a mouse model. Thirty Balb/c mice were divided into Naïve, azoxymethane (AOM)/dextran sodium sulfate (DSS), and ZOL groups. Body weight and small nucleolar RNA host gene 16 (SNHG16) expression, microRNA-146a, and TRAF6 in bone, colon, and stool were investigated. Samples of colon and bone were collected and processed for light microscopic, immunohistochemical staining for cytokeratin 20 (CK20), nuclear protein Ki67 (pKi-67), and caudal type homeobox transcription factor 2 (CDx2) in colon and receptor activator of nuclear factor kB (RANK) and osteoprotegerin (OPG) in bone. A computerized tomography (CT) scan of the femur and tibia was studied. ZOL produced a significant decrease in the expression of SNHG16 and TRAF6 and an increase in miRNA-146a in the colon and bone. ZOL administration improved the histopathological changes in the colon, produced a significant decrease in CK20 and Ki-67, and increased CDx2 expressions. In bone, ZOL prevented osteoporotic changes and tumour cell invasion produced a significant decrease in RANK and an increase in OPG expressions, alongside improved bone mineral density in CT scans. ZOL could be a promising preventive therapy against colitis-induced cancer and associated OP via modulation expression of SNHG16, miRNA-146a, and TRAF6.

BRAF Mutation Is Associated with Hyperplastic Polyp-Associated Gastric Cancer.

Gastric hyperplastic polyps (GHP) are frequently found to be benign polyps and have been considered to have a low carcinogenic potential. The characteristics of the hyperplastic polyp-associated gastric cancer (HPAGC) remain unclear. Therefore, we analyzed samples from 102 GHP patients and identified 20 low-grade atypical GHPs (19.6%), 7 high-grade atypical GHPs (6.9%), and 5 intramucosal cancer samples (4.9%). GHP atypia was more common in the elderly and increased with increasing polyp size. In particular, polyps larger than 1 cm were associated with a higher grade and cancer. Furthermore, mucus production decreased with increasing atypia. Although no correlation was found between atypia and Helicobacter pylori infection or intestinal metaplasia, enhanced proliferative ability (Ki-67) did correlate with atypia, as did nuclear 8-hydroxy-2’-deoxyguanosine levels. Interestingly, 4-hydroxynonenal levels in granulation tissue and the area ratio of granulation tissue within polyps also correlated with GHP atypia. In five cases of HPAGC, three cases exhibited caudal type homeobox transcription factor (CDX2)-positive cells and a mixed mucin phenotype, which is considered to be related to H. pylori infection. By contrast, two cases were CDX2 negative, with a gastric mucin phenotype, and H. pylori infection was not observed in the tumor or the surrounding mucosa. In these cases, a v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutation (V600E) was detected. All cancer samples showed high stemness and p53 protein accumulation, but no KRAS mutations. The molecular and phenotypic characteristics of the cases characterized by BRAF mutations may represent a novel subtype of HPAGC, reflecting a conserved pathway to oncogenesis that does not involve H. pylori infection. These findings are worthy of further investigation in a large-scale study with a substantial cohort of HPAGC patients to establish their clinical significance.

Double Negativity for Expression of YAP1 and CDX2 Defines an Aggressive Type of Colitis-associated Cancer.

Patients with inflammatory bowel disease have markedly increased risk for developing colitis-associated colorectal adenocarcinoma (CAC). There is no established prognostic biomarker for CAC. A retrospective study was performed on a cohort of 57 CACs. Expression of caudal type homeobox transcription factor 2 (CDX2) and YES-associated protein 1 (YAP1) expression was correlated with clinicodemographic and histopathological features. Neither YAP1 nor CDX2 expression alone was significantly associated with tumor invasion beyond the muscularis propria or lymph node status. However, a subgroup of CAC with double negativity for expression of YAP1 and CDX2 was more frequently found in younger patients, and more frequently associated with higher pathological tumor stage and nodal metastasis. Furthermore, a positive correlation between CDX2 and YAP1 expression was identified in CAC and sporadic colorectal adenocarcinoma. Our study demonstrates that double negativity for expression of YAP1 and CDX2 defines a subgroup of CAC with early onset and aggressive clinical features.

Fucoidan suppresses the gastric cancer cell malignant phenotype and production of TGF-β1 via CLEC-2.

The sulfated polysaccharide fucoidan displays excellent anticancer properties with low toxicity in many kinds of cancers. However, its detailed pharmacological effect and mechanism of action in gastric carcinoma remains unclear. In this study, we found that fucoidan could suppress gastric cancer (GC) cell growth, as well as cell migration and invasion. A cytokine expression screen demonstrated that transforming growth factor beta 1 (TGF-β1) secretion was decreased in fucoidan-treated cells. Fucoidan has been reported to be a platelet agonist for the C-type lectin-like receptor 2 (CLEC-2), and our previous research found that upregulation of CLEC-2 inhibited GC progression. Here, we confirmed that fucoidan, combined with CLEC-2, significantly increased CLEC-2 expression in GC cells via the transcription factor caudal type homeobox transcription factor 2, an important regulator of gut homeostasis. In addition, the inhibitory effect of fucoidan on the GC cell malignant phenotype and TGF-β1 secretion could be restored by knocking down CLEC-2. Thus, our data suggest that fucoidan targets CLEC-2 to exert antitumorigenesis and antimetastatic activity, suggesting that fucoidan is a promising treatment for gastric carcinoma.

Value of SATB2, ISL1, and TTF1 to differentiate rectal from other gastrointestinal and lung well-differentiated neuroendocrine tumors

BackgroundManagement of neuroendocrine tumors (NETs) depends on the primary site, but the location of many well-differentiated (WD) NETs is elusive. Organ-specific markers are required for pathological diagnosis from biopsy. Transcription factors with good organ specificity include TTF1 (thyroid transcription factor 1; lung), CDX2 (caudal type homeobox transcription factor 2; midgut), and ISL1 (ISL LIM homeobox 1) and PAX8 (paired box 8) for the pancreas and rectum. SATB2 (SATB homeobox 2) has shown high sensitivity and specificity in colorectal adenocarcinoma. This study determined the viability of SATB2 and other transcription factors as markers, single or in combination, for WD-NETs of various sites. MethodsImmunohistochemical staining of 81 WD-NETs from 8 organ sites was performed to identify SATB2, TTF1, CDX2, ISL1, and PAX8. Receiver operating characteristic (ROC) curves were constructed for different combinations of the 5 markers to determine sensitivity and specificity. ResultsAmong the WD-NETs, SATB2 was predominantly found in those of the rectum; TTF1 in the lung, larynx, and esophagus; and ISL1 in the duodenum and rectum. PAX8 and CDX2 showed poor organ specificity. ROC profiles showed 50% sensitivity and 96% specificity to lung for TTF1+ ISL1–; and 65% sensitivity and 100% specificity to rectum for SATB2+ ISL1– TTF1–. ISL1+ SATB2– TTF1– showed 83% sensitivity and 85% specificity to the duodenum, and 44% sensitivity and 87% specificity to the pancreas. A literature search showed that there was no significant difference in the expression rates of the five transcription factors (TTF1, CDX2, SATB2, PAX8 and ISL1) between primary and metastatic WD-NETs at the same organ when there was a large sample size. ConclusionAmong the 5 transcription factors tested, SATB2 may be a viable marker of WE-NETs of the rectum. The combination of SATB2, ISL1, and TTF1 may help estimate the locations of WD-NETs of unknown origin.

Vulvar Villoglandular Adenocarcinoma of Colonic Type: A Rare Finding

Colonic type villoglandular adenocarcinoma of the lower genital tract is an extremely rare condition. Its origin is not clearly understood; however, the cloacal remnants are the more accepted source for this carcinoma.We report the case of a 67-year-old female patient who presented with a 1.2 cm polypoidal nodule at the right side of the fourchette. Morphologic studies revealed a colonic type mucinous adenocarcinoma that arose from within a villous adenoma. Immunohistochemical staining showed positive cytokeratin 7, cytokeratin 20, carcinoembryonic antigen, P53, and progesterone receptor, but negative for estrogen receptor and caudal type homeobox transcription factor 2. Extensive work-up failed to reveal other primary cancers in this patient. Ultimately, she underwent a radical vulvectomy. No recurrence was seen in eight months follow up of this patient after surgery. Careful, thorough histological evaluation and clinical clues enable correct diagnosis of the rare colonic type vulvar villoglandular adenocarcinoma. Due to rarity of this tumor, its management is questionable. Therefore, additional investigation is necessary for its management.

Nuclear transcription factor caudal type homeobox transcription factor 2 inhibits migration and invasion of gastric cancer cells via Janus kinase/signal transducer activated transcription factors signal pathway

Objective To explore the inhibitory effects of caudal type homeobox transcription factor 2 (CDX2) on migration and invasion of gastric cancer cells via Janus kinase (JAK)/signal transducer activated transcription factors (STAT) signal pathway. Methods Gastric cancer cell MKN-45 was transfected with enhanced green fluorescent protein (EGFP)-N1-CDX2 eukaryotic expression vector and blank plasmid by liposome. The expression of CDX2 was detected by Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Cell viability was measured by methyl thiazol tetrazolium (MTT) assay. Cell migration was examined by scratch test. Cell invasion was examined by Transwell assay. The expression of matrix metalloproteinase (MMP)-2, MMP-9 and JAK/STAT signal pathway related protein was detected by Western blotting. Results As compared with control group, the expression of CDX2 protein (0.18±0.01 vs. 0.82±0.08) and mRNA (0.21±0.01 vs. 0.84±0.08) was up-regulated, the cell viability (0.78±0.07 vs. 0.37±0.03), cell migration distance[(6.82±0.67) vs. (30.73±3.08) nm] and cell invasion number (50.21±5.09 vs. 148.36±13.50) was decreased, the expression of MMP-2 (0.79±0.07 vs. 0.17±0.01), MMP-9 (1.00±0.10 vs. 0.26±0.02), JAK2 (0.49±0.05 vs. 0.22±0.02) and p-STAT3 (1.28±0.12 vs. 0.38±0.03) was down-regulated in the pEGFP-N1-CDX2 group. Conclusion CDX2 could inhibit migration and invasion of MKN-45 cells via inhibition of JAK/STAT signal pathway. Key words: Caudal type homeobox transcription factor 2; Gastric cancer; Migration; Invasion; Janus kinase/signal transducer activated transcription factors signal pathway

Clinicopathological, radiographic, and oncogenic features of primary pulmonary enteric adenocarcinoma in comparison with invasive adenocarcinoma in resection specimens.

Primary pulmonary enteric adenocarcinoma (PEAC) is a rare subtype of primary lung adenocarcinoma. However, it is not known whether there are any distinctive clinical or molecular features.PEACs were retrospectively identified in 28 patients from July 2014 to June 2016. We compared the clinicopathological, radiographic, and oncogenic characteristics of PEAC and primary pulmonary invasive adenocarcinoma (IAC).A total of 28 PEAC patients and 92 IAC patients were compared. PEAC occurred more frequently in males (P = .008), in older patients (P = .041), in those with larger lesions (P = .001), and in those in a more advanced stage (P = .011). Radiologically, PEAC patients had larger lesions (P = .025) and more solid (P = .006); however, there were no statistically significant differences in lobulation, spiculation, pleural indentation, pleural effusion, and lymphadenopathy between PEAC and IAC. PEAC had higher values of carcinoembryonic antigen (P = .008) and carbohydrate antigen 19-9 (P < .001) than IAC. PEAC had a higher incidence (40% vs 63%, P < .001) of Kristen rat sarcoma viral oncogene homolog (KRAS) mutations and a lower incidence (10.71% vs 3.3%, P < .001) of epidermal growth factor receptor (EGFR) mutations. Villin may be a useful marker in the differential diagnosis of PEAC. KRAS mutations occurred more frequently in PEACs, which are cytokeratin 7-negative (P = .032). EGFR mutation rates were higher in PEACs, which are cytokeratin 20- and caudal type homeobox transcription factor 2-negative (P = .041).PEAC is a rare and heterogeneous nonsmall-cell lung cancer subgroup with distinctive clinicopathological, radiographic, and molecular features. These results need to be further confirmed in future studies.

Curcuma wenyujin Y. H. Chen et C. Ling n-Butyl Alcohol Extract Inhibits AGS Cell Helicobacter pyloriCagA+VacA+ Promoted Invasiveness by Down-Regulating Caudal Type Homeobox Transcription Factor and Claudin-2 Expression.

To investigate the effects and possible mechanisms of action of Curcuma wenyujin Y. H. Chen et C. Ling n-Butyl alcohol extract (CWNAE) on repression of human gastric cancer (GC) AGS cell invasion induced by co-culturing with Helicobacter pylori (HP). AGS cells were cultured with HP of positive or negative cytotoxin-associated gene A (CagA) and vacuolating cytotoxin gene A (VacA) expression (CagA+/- or VacA+/-) and divided into 5 group. Group A was cultured without HP as a control, Group B with HPCagA+VacA+, Group C with HPCagA-VacA-, Group D with HPCagA+VacA+ and CWNAE, and Group E with HPCagA-VacA- and CWNAE. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) and tumor invasion assays, examinations of morphology and ultramicroscopic structures, quantitative real-time polymerase chain reaction and Western blots were performed to measure the effects and uncover the mechanisms behind these effects of HPCagA+VacA+ and CWNAE on the epithelial-mesenchymal transition (EMT) of AGS cells. The 10% inhibitory concentration of CWNAE against AGS cells after a 48 h incubation was 19.73±1.30 μg/mL. More AGS cells were elongated after co-culturing with HPCagA+VacA+ than after culturing with HPCagA-VacA-. In tumor invasion assays, HPCagA+VacA+ significantly enhanced the invasiveness of AGS cells compared to the other experimental groups (all P value <0.05), and this effect was inhibited by CWNAE. Treatment with CWNAE normalized tight junctions and reduced the number of pseudopodia of AGS cells co-cultured with HPCagA+VacA+. HPCagA+VacA+ up-regulated zincfinger ebox binding homeobox 1 (ZEB1) in AGS cells after co-culturing for 24 h. Expression of caudal type homeobox transcription factor (CDX-2) and claudin-2 was significantly increased by HPCagA+VacA+ (P<0.05), but not by HPCagA-VacA-. HPCagA+VacA+ promoted the invasiveness of AGS cells through up-regulation of ZEB1 transcription and claudin-2 and CDX-2 expression. CWNAE inhibited these effects of HPCagA+VacA+ on AGS cells by down-regulating ZEB1 transcription, and CDX-2 and claudin-2 expression.

Methylation of promoter region of CDX2 gene in colorectal cancer.

The incidence of colorectal cancer is on the increase owing to changes in daily diet. In the present study, the methylation status of caudal type homeobox transcription factor 2 (CDX2) gene in lesion tissue of colorectal cancer (CRC) was investigated. Additionally, the correlation between the promoter methylation of CDX2 gene, CRC and gene expression in patients with CRC and normal population was examined. Between April 2014 and May 2015 78 cases with CRC were enrolled in the study. Using methylation-specific polymerase chain reaction (PCR), the promoter methylation of CDX2 in normal tissues and colorectal tissues was examinned. Through the fluorescence quantitative PCR technique, the expression levels of CDX2 gene were determined in a normal population and lesion tissue of patients with CRC. At the same time, we evaluated the levels of the CDX2 gene product in the normal population and lesion tissue of patients with CRC. The results showed that the methylation rate of the promoter region of CDX2 gene in normal colorectal tissue was 43.5%, whereas that in the lesion tissue of CRC was 78.5%. The result was statistically significant (P<0.05). The quantity of mRNA and protein expression of CDX2 gene in colorectal and normal tissue was significantly different (P<0.05). In conclusion, the methylation of the CDX2 gene promoter region was associated with risk of CRC, i.e., methylation of the promoter region of CDX2 gene favors the occurrence of CRC.

Protective and therapeutic effects of fucoxanthin against sunburn caused by UV irradiation

Mild exposure to ultraviolet (UV) radiation is also harmful and hazardous to the skin and often causes a photosensitivity disorder accompanied by sunburn. To understand the action of UV on the skin we performed a microarray analysis to isolate UV-sensitive genes. We show here that UV irradiation promoted sunburn and downregulated filaggrin (Flg); fucoxanthin (FX) exerted a protective effect. In vitro analysis showed that UV irradiation of human dermal fibroblasts caused production of intracellular reactive oxygen species (ROS) without cellular toxicity. ROS production was diminished by N-acetylcysteine (NAC) or FX, but not by retinoic acid (RA). In vivo analysis showed that UV irradiation caused sunburn and Flg downregulation, and that FX, but not NAC, RA or clobetasol, exerted a protective effect. FX stimulated Flg promoter activity in a concentration-dependent manner. Flg promoter deletion and chromatin immunoprecipitation analysis showed that caudal type homeo box transcription factor 1 (Cdx1) was a key factor for Flg induction. Cdx1 was also downregulated in UV-exposed skin. Therefore, our data suggested that the protective effects of FX against UV-induced sunburn might be exerted by promotion of skin barrier formation through induction of Flg, unrelated to quenching of ROS or an RA-like action.

Clinicopathological observation of primary lung enteric adenocarcinoma and its response to chemotherapy: A case report and review of the literature

Primary lung enteric adenocarcinoma is a rare type of invasive lung carcinoma. Its morphology and immunohistochemistry are those of colorectal carcinoma, but there is no associated primary colorectal carcinoma. The present study describes the case of a 53-year-old female who presented with an irritating cough and a mass around the right sternoclavicular joint. Comprehensive evaluation revealed involvement of the mediastinum, lungs, right sternoclavicular joint and right kidney. Biopsies from the mediastinal and right sternoclavicular joint tumors showed features of adenocarcinoma. Immunohistochemistry was positive for cytokeratin (CK)20 and caudal type homeobox transcription factor 2, and negative for CK7, thyroid transcription factor-1 and napsin A. Genotypic analysis identified the expression of wild-type epidermal growth factor receptor, Kirsten rat sarcoma viral oncogene homolog, serine/threonine-protein kinase B-Raf and UDP-glucuronosyltransferase 1-1. There was no expression of echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase and a moderate expression of excision repair cross-complementation group 1, ribonucleoside-diphosphate reductase large subunit and tubulin β-3 chain. A strong expression of thymidylate synthase and 677TC genotype expression of methylenetetrahydrofolate reductase was observed. Gastroscopy, enteroscopy, colorectal colonoscopy and positron emission tomography-computed tomography failed to find evidence of a gastrointestinal malignancy and primary lung enteric adenocarcinoma was diagnosed. The presence of multiple metastases did not permit curative surgery. The patient was treated with 3 monthly cycles of the XELOX chemotherapy regimen; the response was poor with progression of supraclavicular lesions. Treatment was switched to the TP regimen for 4 monthly cycles, which resulted in a significant reduction in the size of the lung lesions; however, the supraclavicular lesion responded poorly to the treatment. The patient then received 2 cycles of the FOLFIRI regimen; however, the lung and right supraclavicular lesions progressed, causing increased right upper limb pain. The pain was alleviated by palliative surgery. Following surgery, the DP regimen was employed. Follow-up of the patient remains ongoing. The present findings suggest that the early diagnosis and treatment of primary lung enteric adenocarcinoma is likely to improve patient outcome.

Effect of Rebamipide on the Premalignant Progression of Chronic Gastritis: A Randomized Controlled Study.

Chronic gastritis frequently progresses into precancerous intestinal metaplasia and intraepithelial neoplasia lesions. Rebamipide is a free radical scavenger and we assessed its efficacy on clinical symptoms, gastric mucosal lesions, pathologic grade, and immunohistochemistry in chronic gastritis patients. 178 eligible patients were randomized into treatment and control groups. Both groups followed an optimized lifestyle for 26 weeks, but the treatment group was additionally medicated with rebamipide 0.1 g three times per day. Upper gastrointestinal endoscopy was performed in all patients to evaluate the severity of gastritis by the Modified Lanza Scoring (MLS) and histological changes were evaluated by the Updated Sydney System Score (USSS). Gastric mucosa immunohistochemistry in the treatment group was performed using the intestinal metaplasia markers caudal type homeobox transcription factor 2 (CDX2) and trefoil factor 3 (TFF3) detection. There were significant outcome differences between the treatment and control groups regarding the clinical symptom scores (2.62 ± 1.86 vs. 1.55 ± 1.61, P = 0.0001), gastric mucosal lesion scores (0.57 ± 1.05 vs. 0.16 ± 0.90, P = 0.002), and inflammation (P < 0.05). Only in the treated patients were the rates of intestinal metaplasia (P = 0.017 vs. P = 0.123) and low-grade intraepithelial neoplasia (P = 0.005 vs. P = 0.226) significantly reduced after 26 weeks. The percentages of CDX2 (31.5 vs. 15.7%, P = 0.021) and TFF3 (44.9 vs. 25.8%, P = 0.012) expressing gastric mucosa cells were significantly lower after rebamipide medication than pre-treatment values. Rebamipide improved the clinical symptoms, gastric mucosal lesions, and pathological grades of chronic gastritis patients and decreased the expression rates of CDX2 and TFF3 in gastric cells.

CK7, CK20, SOX10 and CDX2: expressions and diagnostic values in primary adenocarcinoma of the sinonasal tract

To explore the expressions of the cytokeratin 7 (CK7), cytokeratin 20 (CK20), SOX10 and cadual type homeobox transcription factor 2 (CDX2) in primary adenocarcinoma of the sinonasal tract, and evaluate their diagnostic values. A total of 41 paraffin-embeded specimens of primary adenocarcinoma of the sinonasal tract treated in Beijing Tongren Hospital of Capital Medical University were selected from May 2002 to January 2015. All cases were confirmed by histology and clinical data, including 12 cases of non-intestinal sinonasal adenocarcinomas (non-ITACs), 10 cases of intestinal sinonasal adenocarcinomas (ITACs) and 19 cases of salivary gland-type adenocarcinomas (including 12 cases of adenoid cystic carcinomas, 3 cases of polymorphous low grade adenocarcinomas, 2 cases of mucinous adenocarcinomas and 2 cases of acinar cell carcinomas). Expressions of CK7, CK20, SOX10 and CDX2 were assessed by immunohistochemistry staining method. Nuclear staining for CDX2 was identified in all the ITACs,including diffuse nuclear staining in 8 cases and partial nuclear staining in 2 cases. Cytoplasmic staining for CK20 was identified in 9 cases of ITACs, and partial cytoplasmic staining was found in 1 case of non-ITACs, while CK20 was negative in all other adenocarcinomas.Seven cases of ITACs were negative for CK7, while CK7 was positive in all other adenocarcinomas. CK7, but not CDX2 and CK20, was expressed in normal sinonasal epithelium. SOX10 was negative in 10 cases of ITACs and 2 cases of non-ITACs, and positive in all other adenocarcinomas. The sensitivity of CK7-, CK20+, SOX10- and CDX2+ in primary ITACs of the sinonasal tract were 70.0%, 90.0%, 100%, 100%, respectively, and the specificity were 100%, 96.8%, 93.5%, 100%, respectively. Expressions of CK7-, CK20+, SOX10- and CDX2+ have high sensitivity and specificity in ITACs and can be used as a reliable diagnostic marker for primary intestinal-type adenocarcinoma of the sinonasal tract. Additionally, diagnostic value of CDX2 in primary intestinal-type adenocarcinoma of the sinonasal tract is superior to CK20, CK7 and SOX10.

Nuclear transcription factor CDX2 inhibits gastric cancer‑cell growth and reverses epithelial‑to‑mesenchymal transition in vitro and in vivo.

The epithelial‑to‑mesenchymal transition (EMT) has been noted as a critical event in the early step of cancer metastasis. Recent studies showed that nuclear transcription factor caudal type homeobox transcription factor 2 (CDX2) is a prognostic factor, which acts as a marker of good outcome in gastric cancer (GC) patients. However, the association between CDX2 expression and EMT has remained to be fully elucidated. The present study reported that forced overexpression of CDX2 in MKN45/CDX2 cells inhibited GC‑cell growth and proliferation, and attenuated migration and invasion in vitro. Furthermore, MKN45/CDX2 cells exhibited a significant upregulation of E‑cadherin protein and a significant downregulation of vimentin protein expression. These results were further supported by in vivo tumorigenicity assays, which showed that CDX2 suppressed gastric tumor xenograft growth and inhibited EMT in nude mice. These results indicated that CDX2 is capable of inhibiting GC‑cell growth and invasion. CDX2 may participate in the process of EMT of GC cells by regulating the expression of the epithelial and mesenchymal proteins E‑cadherin and vimentin.

Overexpression of caudal type homeobox transcription factor 2 inhibits the growth of the MGC-803 human gastric cancer cell line in vivo.

Caudal type homeobox transcription factor 2 (CDX2) is important in intestinal cell fate specification and multiple lines of evidence have substantiated that CDX2 is important in carcinogenesis of the digestive tract. The CDX2 regulatory network is intricate and remains to be fully elucidated in gastric cancer. The aim of the present study was to examine the effects of CDX2 on the growth of the MGC-803 human gastric cancer cell line in vivo, and to elucidate the mechanism involved. The effects of the overexpression of CDX2 in xenograft tumors of MGC-803 cells was investigated in nude mice through the injection of CDX2 recombinant lentiviral vectors. The tumor size was measured using vernier callipers. The expression levels of CDX2, survivin, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), cyclin D1, s-phase kinase-associated protein 2 (Skp2) and c-Myc in the tumor cells were analyzed by western blotting and semi-quantitative reverse transcription polymerase chain reaction. The apoptotic rates were determined using a terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. The overexpression of CDX2 was observed in the group subjected to the injection of CDX2 recombinant lentiviral vectors. CDX2 had an inhibitory effect on the MGC-803 human gastric cancer cell line and promoted tumor cell apoptosis in vivo. Furthermore, the overexpression of CDX2 upregulated the expression of Bax and downregulated the expression levels of survivin, Bcl-2, cyclin D1, Skp2 and c-Myc in the tumor tissues. These results indicated that CDX2 may serve as a tumor suppressor in gastric cancer, and inhibits gastric cancer cell growth by suppressing the nuclear factor-κB signaling pathway.

Distinct patterns of DNA methylation in conventional adenomas involving the right and left colon

Recent studies have shown two distinct non-CIMP methylation clusters in colorectal cancer, raising the possibility that DNA methylation, involving non-CIMP genes, may play a role in the conventional adenoma–carcinoma pathway. A total of 135 adenomas (65 left colon and 70 right colon) were profiled for epigenome-wide DNA methylation using the Illumina HumanMethylation450 BeadChip. A principal components analysis was performed to examine the association between variability in DNA methylation and adenoma location. Linear regression and linear mixed effects models were used to identify locus-specific differential DNA methylation in adenomas of right and left colon. A significant association was present between the first principal component and adenoma location (P=0.007), even after adjustment for subject age and gender (P=0.009). A total of 168 CpG sites were differentially methylated between right- and left-colon adenomas and these loci demonstrated enrichment of homeobox genes (P=3.0 × 10−12). None of the 168 probes were associated with CIMP genes. Among CpG loci with the largest difference in methylation between right- and left-colon adenomas, probes associated with PRAC (prostate cancer susceptibility candidate) gene showed hypermethylation in right-colon adenomas whereas those associated with CDX2 (caudal type homeobox transcription factor 2) showed hypermethylation in left-colon adenomas. A subgroup of left-colon adenomas enriched for current smokers (OR=6.1, P=0.004) exhibited a methylation profile similar to right-colon adenomas. In summary, our results indicate distinct patterns of DNA methylation, independent of CIMP genes, in adenomas of the right and left colon.

CDX2is an amplified lineage-survival oncogene in colorectal cancer

The mutational activation of oncogenes drives cancer development and progression. Classic oncogenes, such as MYC and RAS, are active across many different cancer types. In contrast, "lineage-survival" oncogenes represent a distinct and emerging class typically comprising transcriptional regulators of a specific cell lineage that, when deregulated, support the proliferation and survival of cancers derived from that lineage. Here, in a large collection of colorectal cancer cell lines and tumors, we identify recurrent amplification of chromosome 13, an alteration highly restricted to colorectal-derived cancers. A minimal region of amplification on 13q12.2 pinpoints caudal type homeobox transcription factor 2 (CDX2), a regulator of normal intestinal lineage development and differentiation, as a target of the amplification. In contrast to its described role as a colorectal tumor suppressor, CDX2 when amplified is required for the proliferation and survival of colorectal cancer cells. Further, transcriptional profiling, binding-site analysis, and functional studies link CDX2 to Wnt/β-catenin signaling, itself a key oncogenic pathway in colorectal cancer. These data characterize CDX2 as a lineage-survival oncogene deregulated in colorectal cancer. Our findings challenge a prevailing view that CDX2 is a tumor suppressor in colorectal cancer and uncover an additional piece in the multistep model of colorectal tumorigenesis.

KRAS Mutation Analysis Helps to Differentiate Between Pulmonary Metastasis from Colon Adenocarcinoma In Situ and Primary Lung Adenocarcinoma

A 69-year-old woman never-smoker was noted to have a solitary 4-cm lesion in the left upper lobe on routine preoperative chest x-ray before elective hip replacement. Chest computed tomography redemonstrated the spiculated 4 3.3-cm lesion. Positron emission tomography-computed tomography confirmed that the lesion was fluorodeoxyglucose-avid with no other sites of fluorodeoxyglucose avidity (Figure 1). The patient underwent a core needle biopsy of the lung lesion showing a cytokeratin (CK) 20 and caudal type homeobox transcription factor 2–positive adenocarcinoma, which was negative for CK7 and thyroid transcription factor-1. The expected immunohistochemical markers for a primary lung adenocarcinoma are CK7 and thyroid transcription factor-1, whereas the usual markers for a primary colorectal adenocarcinoma are CK20 and caudal type homeobox transcription factor 2. The patient underwent a video-assisted thoracoscopic lobectomy and mediastinal lymphadenectomy revealing a 3.8-cm adenocarcinoma with the same histologic (Figure 2A) and immunophenotype (Figure 3) as the previous biopsy. One inferior mediastinal lymph node (level 9L) was also involved with tumor, and levels 5, 10L, 11L, and 12L nodes were negative for disease. A colonoscopy, upper endoscopy, and capsule video enteroscopy did not show any evidence of a primary tumor. Seven years before the discovery of the lung mass, she had a 2-cm sigmoid adenoma with areas of high-grade dysplasia (Figure 2B) and carcinoma in situ resected endoscopically in a piecemeal fashion. Her resected lung tumor was sent for genetic testing and found to harbor a Kirsten ras sarcoma viral oncogene homolog (KRAS) gene codon 12 GGT to GTT (glycine to valine) missense mutation (KRAS G12V). The tumor was wild-type for the epidermal growth factor receptor gene. Given there was no evidence of primary colorectal tumor on endoscopy, the archived, paraffin-embedded sigmoid adenoma was also genotyped and found to carry the same KRAS codon 12 GTT transversion. This suggested that the lung tumor was a late recurrence from the original KRAS mutant sigmoid carcinoma in situ. She was subsequently found to have multiple new pulmonary lesions.

Abstract 2130: Genomic profiling identifies CDX2 as a lineage-dependent oncogene amplified in colorectal cancer

Abstract Somatic DNA alteration underlies tumor development and progression, and gives rise to tumors with diverse genetic contexts. Characterizing these contexts helps identify driving genetic lesions and potential therapeutic vulnerabilities. Here, we surveyed a collection of 29 colorectal cancer cell lines for DNA copy number alterations and identified in a subset of samples gain/amplification on chromosome 13, which was well represented among the genomic profiles of 344 primary colorectal tumors examined, but not in other tumor types. A minimal region of high-level amplification on 13q12.2, containing the caudal type homeobox transcription factor CDX2, was identified in one cell line and 7 of 123 (6%) primary colorectal tumors. A tissue microarray consisting of an independent set of 83 colorectal tumors confirmed the presence of a subset of tumors harboring copy number gain/amplification of 13q with increased CDX2 protein expression. In the context of genomic amplification, RNA interference experiments showed CDX2 is required for proliferation of colorectal cancer cells and promotes cell cycle progression without an effect on apoptosis. CDX2 is a known transcriptional regulator of normal gut development and intestinal epithelial cell differentiation and maintenance. Here we have shown that for a subset of lineage-derived colorectal tumors, cell proliferation is dependent on the abnormal amplification and overexpression of CDX2. Thus, we nominate CDX2 as a novel lineage-dependent oncogene deregulated in colorectal cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2130.