CDX2 Biomarker Testing and Adjuvant Therapy for Stage II Colon Cancer: An Exploratory Cost-Effectiveness Analysis.

OBJECTIVES: Adjuvant chemotherapy is not recommended for patients with average-risk stage II (T3N0) colon cancer. Nevertheless, a subgroup of these patients who are CDX2-negative might benefit from adjuvant chemotherapy. We evaluated the cost-effectiveness of testing for the absence of CDX2 expression followed by adjuvant chemotherapy (fluorouracil combined with oxaliplatin [FOLFOX]) for patients with stage II colon cancer. METHODS: We developed a decision model to simulate a hypothetical cohort of 65-year-old patients with average-risk stage II colon cancer with 7.2% of these patients being CDX2-negative under 2 different interventions: (1) test for the absence of CDX2 expression followed by adjuvant chemotherapy for CDX2-negative patients and (2) no CDX2 testing and no adjuvant chemotherapy for any patient. We derived disease progression parameters, adjuvant chemotherapy effectiveness and utilities from published analyses, and cancer care costs from the Surveillance, Epidemiology, and End Results (SEER)-Medicare data. Sensitivity analyses were conducted. RESULTS: Testing for CDX2 followed by FOLFOX for CDX2-negative patients had an incremental cost-effectiveness ratio of $5500/quality-adjusted life-years (QALYs) compared with no CDX2 testing and no FOLFOX (6.874 vs 6.838 discounted QALYs and $89 991 vs $89 797 discounted US dollar lifetime costs). In sensitivity analyses, considering a cost-effectiveness threshold of $100 000/QALY, testing for CDX2 followed by FOLFOX on CDX2-negative patients remains cost-effective for hazard ratios of <0.975 of the effectiveness of FOLFOX in CDX2-negative patients in reducing the rate of developing a metastatic recurrence. CONCLUSIONS: Testing tumors of patients with stage II colon cancer for CDX2 and administration of adjuvant treatment to the subgroup found CDX2-negative is a cost-effective and high-value management strategy across a broad range of plausible assumptions.

P63 Deficiency and CDX2 Overexpression Lead to Barrett's-Like Metaplasia in Mouse Esophageal Epithelium.

BACKGROUND: The cellular origin and molecular mechanisms of Barrett's esophagus (BE) are still controversial. Trans-differentiation is a mechanism characterized by activation of the intestinal differentiation program and inactivation of the squamous differentiation program. AIMS: Renal capsule grafting (RCG) was used to elucidate whether CDX2 overexpression on the basis of P63 deficiency in the esophageal epithelium may generate intestinal metaplasia. METHODS: P63-/-;Villin-Cdx2 embryos were generated by crossing P63+/- mice with Villin-Cdx2 mice. E18.5 esophagus was xenografted in a renal capsule grafting (RCG) model. At 1, 2, or 4 weeks after RCG, the mouse esophagus was immunostained for a proliferation marker (BrdU), squamous transcription factors (SOX2, PAX9), squamous differentiation markers (CK5, CK4, and CK1), intestinal transcription factors (CDX1, HNF1α, HNF4α, GATA4, and GATA6), intestinal columnar epithelial cell markers (A33, CK8), goblet cell marker (MUC2, TFF3), Paneth cell markers (LYZ and SOX9), enteroendocrine cell marker (CHA), and Tuft cell marker (DCAMKL1). RESULTS: The P63-/-;Villin-Cdx2 RCG esophagus was lined with proliferating PAS/AB+ cuboidal cells and formed an intestinal crypt-like structure. The goblet cell markers (TFF3 and MUC2) and intestinal transcription factors (CDX1, HNF1α, HNF4α, GATA4, and GATA6) were expressed although no typical morphology of goblet cells was observed. Other intestinal cell markers including enteroendocrine cell marker (CHA), Paneth cell markers (LYZ and Sox9), and intestinal secretory cell marker (UEA/WGA) were also expressed in the P63-/-;Villin-Cdx2 RCG esophagus. Squamous cell markers (PAX9 and SOX2) were also expressed, suggesting a transitional phenotype. CONCLUSION: CDX2 overexpression on the basis of P63 deficiency in esophageal epithelial cells induces Barrett's-like metaplasia in vivo. Additional factors may be needed to drive this transitional phenotype into full-blown BE.

Complete remission of Cdx-2 positive primary testicular carcinoid tumor: 10-years follow-up and literature review.

BACKGROUND: The neuroendocrine cells can cause a variety of malignancies throughout the human body known as the neuroendocrine tumors (NETs) or carcinoid tumors. The primary testicular carcinoid tumor (PTCT) accounts for less than 1% of the testicular neoplasms and for only 0.2% of all carcinoid tumors representing already a very rare neoplastic entity. Here, we present a patient with a history of an exceptionally rare primary testicular carcinoid tumor, staining positive for Cdx-2 along with a literature review. CASE PRESENTATION: A 44-year old patient without significant past medical history was diagnosed in September 2009 with primary testicular carcinoid tumor, which was surprisingly staining positively for Cdx-2, too. At the time of the initial diagnosis the tumor was already showing histopathological infiltration of veins. DOTA-TATE-PET/CT imaging and endoscopy studies did not show any signs of distant metastases and in particular no gastrointestinal manifestation following no further medical indication for systemic chemotherapy. The continuous and close follow-up of the patient has reached a total of over 10 years at the time of publication remaining in complete remission. CONCLUSION: The diagnosis of primary testicular carcinoid is based on histopathology. The detailed histopathologic assessment of biomarkers based on immunohistochemistry is very important for the classification and the prognosis of the primary testicular carcinoid tumor. Primary testicular carcinoid tumor with Cdx-2 positive stain outlines an exceptionally rare neoplastic entity without a consensus about general follow-up guidelines, requiring close clinical and imaging aftercare and consideration in Cdx-2 positive metastatic tumor of unknown origin.

Expression patterns of seven key genes, including ß-catenin, Notch1, GATA6, CDX2, miR-34a, miR-181a and miR-93 in gastric cancer.

Gastric cancer (GC) is one of the most prevalent cancers and a major cause of cancer related mortality worldwide. Incidence of GC is affected by various factors, including genetic and environmental factors. Despite extensive research has been done for molecular characterization of GC, it remains largely unknown. Therefore, further studies specially conducted among various ethnicities in different geographic locations, are required to know the precise molecular mechanisms leading to tumorigenesis and progression of GC. The expression patterns of seven candidate genes, including ß-catenin, Notch1, GATA6, CDX2, miR-34a, miR-181a, and miR-93 were determined in 24 paired GC tissues and corresponding non-cancerous tissues by quantitative Real-Time PCR. The association between the expression of these genes and clinicopathologic factors were also investigated. Our results demonstrated that overall mRNA levels of GATA6 were significantly decreased in the tumor samples in comparison with the non-cancerous tissues (median fold change (FC) = 0.3143; P = 0.0003). Overall miR-93 levels were significantly increased in the tumor samples relative to the non-cancerous gastric tissues (FC = 2.441; P = 0.0002). ß-catenin mRNA expression showed a strong positive correlation with miR-34a (r = 0.5784; P = 0.0031), and miR-181a (r = 0.5652; P = 0.004) expression. miR-34a and miR-181a expression showed a significant positive correlation (r = 0.4862; P = 0.016). Moreover, lower expression of Notch1 was related to distant metastasis in GC patients with a borderline statistical significance (p = 0.0549). These data may advance our understanding of the molecular biology that drives GC as well as provide potential targets for defining novel therapeutic strategies for GC treatment.

CDX2, SATB2, GATA3, TTF1, and PAX8 Immunohistochemistry in Krukenberg Tumors.

Twenty-six Krukenberg tumors (16 lower gastrointestinal, 4 upper gastrointestinal, and 6 of unknown origin) and their primaries when known were stained with CDX2, SATB2, GATA3, TTF1, and PAX8 using a tissue microarray containing predominantly or exclusively signet ring cells. The most common primary was appendiceal mixed adenoneuroendocrine carcinoma. CDX2 and SATB2 were positive in all known lower gastrointestinal primary tumors and negative in nearly all known upper gastrointestinal primary tumors. Primaries showed identical immunophenotypes to their metastases. Among cases of unknown primary origin, 3 were positive and 3 were negative for CDX2 and SATB2. Chest images, upper endoscopies, colonoscopies, appendectomies, and mammogram were performed with negative results in all, 4, 2, 2, and 1 cases, respectively. No cystoscopies were attempted. PAX8, GATA3, and TTF1 were negative in all cases. The literature was reviewed with emphasis on immunohistochemistry of signet ring cell-containing carcinomas from the appendix, colon, stomach, breast, lung, and bladder. Three quarters of gastric primaries stain for CDX2 and only rare examples stain for SATB2. Colorectal primaries (most of them) and appendiceal primaries (all of them) are positive for CDX2 and SATB2. GATA3 stains almost all breast primaries and approximately half of bladder primaries. All pulmonary primaries are positive for TTF1. PAX8 is negative in the gastric, colorectal, and appendiceal primaries reported. This study shows that the panel of immunostains is useful in confirming the site of origin of a metastatic Krukenberg tumor when one is known and has limited diagnostic value for diagnosing metastases of unknown origin.

Directed differentiation of human induced pluripotent stem cells into mature stratified bladder urothelium.

For augmentation or reconstruction of urinary bladder after cystectomy, bladder urothelium derived from human induced pluripotent stem cells (hiPSCs) has recently received focus. However, previous studies have only shown the emergence of cells expressing some urothelial markers among derivatives of hiPSCs, and no report has demonstrated the stratified structure, which is a particularly important attribute of the barrier function of mature bladder urothelium. In present study, we developed a method for the directed differentiation of hiPSCs into mature stratified bladder urothelium. The caudal hindgut, from which the bladder urothelium develops, was predominantly induced via the high-dose administration of CHIR99021 during definitive endoderm induction, and this treatment subsequently increased the expressions of uroplakins. Terminal differentiation, characterized by the increased expression of uroplakins, CK13, and CK20, was induced with the combination of Troglitazone + PD153035. FGF10 enhanced the expression of uroplakins and the stratification of the epithelium, and the transwell culture system further enhanced such stratification. Furthermore, the barrier function of our urothelium was demonstrated by a permeability assay using FITC-dextran. According to an immunohistological analysis, the stratified uroplakin II-positive epithelium was observed in the transwells. This method might be useful in the field of regenerative medicine of the bladder.

Transcription factor Oct1 protects against hematopoietic stress and promotes acute myeloid leukemia.

A better understanding of the development and progression of acute myelogenous leukemia (AML) is necessary to improve patient outcome. Here we define roles for the transcription factor Oct1/Pou2f1 in AML and normal hematopoiesis. Inappropriate reactivation of the CDX2 gene is widely observed in leukemia patients and in leukemia mouse models. We show that Oct1 associates with the CDX2 promoter in both normal and AML primary patient samples, but recruits the histone demethylase Jmjd1a/Kdm3a to remove the repressive H3K9me2 mark only in malignant specimens. The CpG DNA immediately adjacent to the Oct1 binding site within the CDX2 promoter exhibits variable DNA methylation in healthy control blood and bone marrow samples, but complete demethylation in AML samples. In MLL-AF9-driven mouse models, partial loss of Oct1 protects from myeloid leukemia. Complete Oct1 loss completely suppresses leukemia but results in lethality from bone marrow failure. Loss of Oct1 in normal hematopoietic transplants results in superficially normal long-term reconstitution; however, animals become acutely sensitive to 5-fluorouracil, indicating that Oct1 is dispensable for normal hematopoiesis but protects blood progenitor cells against external chemotoxic stress. These findings elucidate a novel and important role for Oct1 in AML.

Leptin treatment of in vitro cultured embryos increases outgrowth rate of inner cell mass during embryonic stem cell derivation.

Leptin, a metabolic hormone, regulates the reproductive functions responding to both nutritional and body conditions. Embryonic stem cells play important roles in reproductive technology, but their derivation can be challenging. In this study, we evaluated the derivation rates of mouse embryonic stem cell (mESC) line from blastocysts developing in embryo culture media supplemented with different leptin concentrations. The results showed that addition of leptin into the embryo culture medium supported the in vitro development of mouse embryo. The mESC line derivation rates for media treated with 0, 10, 50, and 100 ng/ml of leptin were 61.24 % (54/88), 84.96 % (42/50), 81.79 % (61/76), and 85.78 % (56/67), respectively. In addition, leptin treatment of blastocysts upregulated the expression levels of the trophectoderm marker Cdx2, whereas inner cell mass markers Oct-4 and Nanog were not affected. mESC lines derived after leptin treatment demonstrated hallmarks of pluripotency, such as alkaline phosphatase activity, expression of, OCT4, NANOG, and SSEA1, as well as the ability to form embryoid bodies and well-differentiated teratomas. In conclusion, leptin has a positive effect on the derivation rate of mouse embryonic stem cell lines which may be, in part, due to its effects on the development of the trophectoderm cell lineage in the embryo.

Prognostic influence of CDX2 expression in gastric carcinoma after surgery with a curative intent.

INTRODUCTION AND OBJECTIVES: CDX2 is a specific transcription factor with a significant role in the early differentiation and maintenance of intestinal epithelial cells during gastrointestinal development and also as a tumor suppressor. The aim of this study was to assess the potential role of CDX2 expression as a prognostic predictor. MATERIAL AND METHODS: ninety-two of 206 (44.6%) patients with gastric carcinoma that underwent a curative surgery and had immunohistochemical staining for CDX2 were enrolled into the study; 51.1% were female and the average age was 74.07 years. Overall, 56.5% of tumors were of the intestinal type, 33.7% were diffuse and 9.8% were mixed; 23.9% were T1/T2, 76.1% were T3/T4 and lymph node metastases (N+) were identified in 69.6% of cases; 13% (12) were clinical stage I, 40.2% (37) were stage II and 46.7% (43) were stage III. RESULTS: a total of 68.5% (63) expressed CDX2. Our study suggests that CDX2 expression (HR = 0.339, p = 0.024) represents an independent risk marker together with the Lauren type (HR = 3.471, p = 0.022). There was association between a milder clinical stage and CDX2 expression (stage I) (p = 0.046). A significant difference was found in overall survival that favored patients with positive CDX2 expression (85.7% vs 65.5%, p = 0.012). CONCLUSION: our results confirm that CDX2 expression in gastric carcinoma is associated with improved prognosis, although further studies are needed to draw definitive conclusions.

Prognostic value of low CDX2 expression in colorectal cancers with a high stromal content - a short report.

PURPOSE: Lack of expression of the intestinal transcription factor CDX2 in colorectal cancer (CRC) identifies patients with a poor prognosis. This biomarker has previously been suggested to be prognostic in CRCs with a high stromal content based on mRNA expression data. We investigated the prognostic value of CDX2 expression in microsatellite stable CRC stratified by stromal content using microscopy-based techniques. METHODS AND RESULTS: The study included a cohort of 236 patients with stage I-IV CRC. We assessed by microscopy the tumour-stroma ratio (TSR) and the immunohistochemical CDX2 intensity. We found that patients of the stroma-high group had a worse prognosis compared to those of the stroma-low group [disease-free survival in a multivariate analysis (DFSmultivariate) HR 1.52 (95% CI 1.05-2.21)]. In our cohort, low CDX2 expression (14.6%) showed prognostic value for DFSmultivariate [HR 1.93 (95% CI 1.16-3.23)]. Interestingly, when stratifying the cohort by TSR, no prognostic difference was observed related to CDX2 expression in stroma-low tumours. However, CDX2 expression was found to be prognostic within the stroma-high group [DFSmultivariate HR 3.02 (95% CI 1.49-6.13)]. The p value for interaction between TSR and CDX2 status was borderline significant in DFS (p = 0.071). CONCLUSIONS: The present study confirms a poor outcome of patients with stroma-high tumours. Low CDX2 expression in tumours with a high stromal content identified patients with a particularly poor prognosis. The present study did not reveal a clear difference in TSR associated with CDX2 status and survival. This method, solely based on microscopy, identifies patients who have a high risk of relapse and a poor outcome, and who may benefit from targeted therapy.

Nuclear ß-catenin and CDX2 expression in ovarian endometrioid carcinoma identify patients with favourable outcome.

AIMS: Ovarian endometrioid carcinoma (EC) generally has a good prognosis. Adjuvant chemotherapy can be spared in low-stage disease, but prognostic biomarkers are needed to refine the treatment threshold. Wnt/ß-catenin signalling is commonly altered in EC. We examined immunohistochemical expression of nuclear ß-catenin and CDX2 as prognostic biomarkers for EC; both are mediators of the Wnt pathway. METHODS AND RESULTS: We evaluated two ovarian EC cohorts, discovery set (n = 183) and validation set (n = 174), with ovarian cancer-specific survival (OCSS) as the primary end-point. In univariable analysis, nuclear ß-catenin expression was significantly associated with longer OCSS in the discovery set [hazard ratio (HR) = 0.36, 95% confidence interval (CI) = 0.16-0.74, P = 0.004] and the validation set (HR = 0.35, 95% CI = 0.11-0.89, P = 0.006). Similar significant associations were observed with CDX2 expression in the discovery set (HR = 0.25, 95% CI = 0.11-0.50, P < 0.001) and validation set (HR = 0.27, 95% CI = 0.07-0.75, P = 0.020). In multivariable analysis, combined positivity of both markers was significantly associated with longer OCSS in the discovery set (HR = 0.20, 95% CI = 0.06-0.49, P < 0.001) and in the validation set (HR = 0.33 95% CI = 0.07-0.1.06, P = 0.047). In a stratified analysis for stage IC/II EC, combined positivity identified a subset of patients with a significantly longer OCSS in the discovery cohort but only a non-significant trend in the validation cohort. CONCLUSIONS: Nuclear ß-catenin and CDX2 expression individually or in combination are validated prognostic markers for ovarian EC. However, their full potential to stratify low risk patients at adjuvant threshold awaits further multimarker study.

Impact of CDX2 expression status on the survival of patients after curative resection for colorectal cancer liver metastasis.

BACKGROUND: The prognostic biomarker for patients undergoing curative liver metastasectomy for colorectal cancer (CRC) is lacking. The purpose was to investigate the prognostic role of a lack of CDX2 expression, which has been proposed as a potential biomarker for high-risk relapse in early-stage CRC, in patients undergoing curative liver metastasectomy. METHODS: A total of 396 consecutive patients with CRC liver metastasis who underwent potentially curative liver metastasectomy at a single center in Japan between 2005 and 2015 were included. For the immunohistochemical analysis of nuclear CDX2 expression, we adopted the tissue microarray approach using the resected metastatic liver CRCs. Patient subgroups were compared with respect to disease-free survival (DFS) and overall survival (OS) by applying the Kaplan-Meier curve, log-rank tests, and multivariate analyses based on the Cox proportional hazards method. OS is defined as the period from the date of curative liver resection for metastatic CRC until death. DFS is defined as the length of time from curative liver resection to either the first recurrence or death. In patients without recurrence, the latest imaging inspection date was used as the censored date. RESULTS: Thirty-six of the 396 CRCs (9.1%) reduced CDX2 expression. The reduced expression of CDX2 was associated with poor differentiation (P = 0.02). DFS in days was lower in the patients with CDX2-low CRC than in the patients with CDX2-high CRC (median DFS: 245 days versus 420 days; hazard ratio for disease recurrence: 1.64; 95% confidence interval: 1.08-2.38; P = 0.02). OS in days was lower in the patients with CDX2-low CRC than in the patients with CDX2-high CRC (median OS: 1024 days versus 3145 days; hazard ratio: 2.41; 95% confidence interval: 1.52-3.85; P <  0.001). In patients with CDX2-low CRC, both DFS and OS were similar between the with and without pre- or post-operative chemotherapy groups (median DFS: 243 versus 247 days; P = 0.73, median OS: 1016 versus 1363 days; P = 0.69). CONCLUSIONS: Reduced expression of CDX2 indicates poor DFS and OS, however, it might not represent chemosensitivity in patients undergoing curative liver metastasectomy. (339/350).

The expression of TTF1, CDX2 and ISL1 in 74 poorly differentiated neuroendocrine carcinomas.

BACKGROUND: The expression profile of immunohistochemical markers of origin in poorly differentiated neuroendocrine carcinoma (PDNEC) is not well studied. MATERIALS AND METHODS: Seventy-four PDNECs from gastroenteropancreatic (GEP) organs and the lung, including 48 large cell NEC (LCNEC) and 26 small cell carcinomas (SmCC), were subject to immunohistochemical staining for CDX2, TTF1 and ISL1. The staining intensity (1 to 3) and percentage of positive tumor cells [0 (negative), 1 (<50%) and 2 (≥50%)] were assessed. The multiplicative index (maximum 6) was calculated and the average total score (aTS) was determined for each primary site and histologic subtype. RESULTS: In the 38 GEP and 36 lung PDNECs, CDX2, TTF1 and ISL1 staining was observed in 71% (aTS 2.8), 16% (aTS 0.4), 63% (aTS 1.9), and 22% (aTS 0.6), 72% (aTS 2.9) and 92% (aTS 3.8), respectively. GEP PDNECs showed a higher aTS for CDX2 and lower aTS for TTF1 and ISL1, compared to that of lung PDNECs (Student's t-test, p < 0.001). SmCC had a higher aTS for TTF1 and ISL1 (p < 0.001) and lower aTS for CDX2 (p < 0.002) than that of LCNEC. CONCLUSIONS: CDX2 and TTF1 demonstrate potential utility in suggesting the primary site of PDNEC. In addition, CDX2 may be useful in supporting the diagnosis of LCNEC in cases with overlapping or borderline morphology. Utility of ISL1 as an adjunctive diagnostic marker of SmCC remains to be studied.

Asynchronous CDX2 expression and polarization of porcine trophoblast cells reflects a species-specific trophoderm lineage determination progress model.

Upregulation of Cdx2 expression in outer cells is a key event responsible for cell lineage segregation between the inner cell mass and the trophoderm (TE) in mouse morula-stage embryos. In TE cells, polarization can regulate Hippo and Rho-associated kinase (Rho-ROCK) signaling to induce the nuclear location of YAP, which has been demonstrated to further induce the expression of Cdx2. However, we found that CDX2 expression could not be detected in the outer cells of porcine morula-stage embryos but only in some TE cells at the early blastocyst stage. The biological significance and the regulation mechanism of this species-specific CDX2 expression pattern have still not been determined. We show here that an asynchronous CDX2 expression pattern exists in porcine TE cells during the development of the blastocyst. We demonstrate that CDX2 expression in porcine TE cells depends on the nuclear localization of YAP and polarization of the embryo through Y27632 treatment. We found that the polarization process in the morula to the late blastocyst stage porcine embryos was asynchronous, which was revealed by the apical localization of phosphorylated EZRIN staining. Artificially enhancing the number of polarized blastomeres by culturing the separated blastomeres of four-cell stage porcine embryos resulted in increased CDX2-positive cell numbers. These results indicate that the mechanism of CDX2 expression regulation is conserved, but the polarization progress is not conserved between the pig and the mouse, and results in a species-specific trophoblast determination progress model.

The prognostic impact of CDX2 correlates with the underlying mismatch repair status and BRAF mutational status but not with distant metastasis in colorectal cancer.

Loss of CDX2 expression has been proposed to be a prognostic biomarker in colorectal cancer (CRC) correlating with shorter overall (OS) and progression-free survival (PFS). Since metastatic disease, mismatch repair (MMR) deficiency, and the mutational status of BRAF are considered to be important prognostic determinants in CRC, the present study aimed to analyze CDX2 expression in correlation with these parameters. Immunohistochemistry for CDX2, hMLH1, and hMSH2 was applied to a study cohort of 503 CRC specimens (FIRE-3) and a matched case-control collection of 50 right-sided CRC specimens with synchronous distant metastases and 50 right-sided CRCs without distant metastases. Furthermore, the mutational status of BRAF gene was analyzed utilizing pyrosequencing. CDX2 expression significantly correlates with reduced OS (p = 0.008) within the study population. In both cohorts, a significant correlation of CDX2 expression and MMR deficiency as well as the presence of a BRAF mutation (each p > 0.001) was observed, whereas no correlation of CDX2 expression and synchronous metastasis could be obtained. In the case-control study, only patients with proficient MMR status showed a correlation of CDX2 loss and synchronous metastasis, whereas in patients with deficient MMR status and CDX2 loss, no distant metastases at the time of diagnosis were found (p = 0.003). We could demonstrate that the reduced OS of CDX2-negative CRC patients is not caused by higher rates of distant metastases. Furthermore, our data indicate that the prognostic impact of CDX2 depends on the MMR status and the BRAF mutational status of the tumors. Thus, it could be concluded that CDX2 is not an independent prognostic biomarker in CRC.

Association of CDX2 Expression With Survival in Early Colorectal Cancer: A Systematic Review and Meta-analysis.

CDX2 is a homeobox gene encoding transcriptional factors for intestinal organogenesis and represents a specific marker of colorectal adenocarcinoma (CRC) differentiation. We have evaluated if CDX2 expression is associated with better overall and disease-free survival (OS and DFS) in patients with CRC. PubMed, SCOPUS, EMBASE, The Cochrane Library, and Web of Science (from inception to July 2017) were systematically reviewed for relevant studies on adult patients with CRC where OS and DFS were calculated according to CDX2 expression in uni- or multivariate analysis were included. Hazard ratio (HR) for mortality and/or disease progression was calculated. The search produced 16 studies suitable for inclusion (6291 individual patients). The meta-analysis showed a reduced risk of death for patients with CDX2-positive CRC in 14 studies (HR, 0.5; 95% confidence interval [CI], 0.38-0.66; P < .001 according to random effect model). In 6 studies where only DFS data was available, CDX2 expression led to a 52% lower risk of relapse or death (HR, 0.48; 95% CI, 0.39-0.59; P < .001 according to random effect model). The results did not change as a function of ethnicity, type of study, CDX2 detection modality, or stage. Interestingly, in stages II to III, CDX2 expression was associated with a 70% lower risk of death (HR, 0.3; 95% CI, 0.12-0.77; P = .01). CDX2 expression confirms to be a strong prognostic factor in stage II and III CRC. In this setting, along with other clinical and pathologic factors, the lack of expression of CDX2 may be considered an important variable when deciding for adjuvant chemotherapy.

CDX2 and LEF-1 expression in pilomatrical tumors and their utility in the diagnosis of pilomatrical carcinoma.

BACKGROUND: The Wnt signaling pathway has been implicated in the pathogenesis of pilomatrical tumors. Lymphoid enhancer-binding factor 1 (LEF-1) is a downstream component of this pathway, and Caudal-related homeobox transcription factor 2 (CDX2) has been postulated to regulate it, but little is known about expression of these transcription factors in pilomatrical tumors. METHODS: Immunohistochemistry for CDX2, ß-catenin, LEF-1, CK19, CK5, Special AT-rich sequence- binding protein 2 (SATB2), cadherin 17 and androgen receptor was performed on pilomatricomas (PMs) (N = 12), pilomatrical carcinomas (PMCAs) (N = 12) and non-pilomatrical cutaneous tumors (N = 18). RESULTS: PMs and PMCAs were positive for CDX2 (9/12 PMs, sensitivity = 75%, specificity = 100%; 11/12 PMCAs, sensitivity = 92%, specificity = 100%; P < 0.01), ß-catenin (12/12 PMs, sensitivity = 100%, specificity = 94%; 10/12 PMCAs, sensitivity = 83%, specificity = 94%; P < 0.01) and LEF-1 (12/12 PMs, sensitivity = 100%, specificity = 56%; 12/12 PMCAs, sensitivity = 100%, specificity = 56%; P < 0.01). CDX2 expression was commonly focal, within a discrete subpopulation of squamoid cells. The LEF-1 expression pattern was different and discernable between pilomatrical tumors (strong, diffuse) and non-pilomatrical tumors (weak, patchy). CONCLUSION: This study reaffirms the importance of the Wnt signaling pathway in the tumorigenesis of pilomatrical tumors, and this introduces CDX2 as a possible regulator and marker of pilomatrical tumorigenesis. LEF-1 and CDX2 performed at least as well as ß-catenin, if not better when taking into account expression pattern, as a diagnostic marker for PMCA, and should be considered in the workup of ambiguous primitive-appearing cutaneous tumors.

Esophagogastric Junction Carcinomas - Discriminating Histological Types Through Immunohistochemistry.

BACKGROUND/AIM: Although differentiating squamous cell carcinoma (SCC) from adenocarcinoma (AC) at the esophagogastric junction (EGJ) is important for the choice of treatment, this can occasionally be difficult with small biopsy specimens. Therefore, the purpose of this study was to determine the most useful immunomarker panel for discriminating between SCC and AC of the EGJ. MATERIALS AND METHODS: We analyzed 15 SCCs and 26 ACs of the EGJ obtained surgically using immunohistochemistry. RESULTS: The sensitivities of p40, p63 and cytokeratin 5/6 were 100% with specificities of 88%, 46% and 81%, respectively, for SCC. The sensitivities of CAM5.2, caudal-type homeobox 2 (CDX2), mucin-5AC (MUC-5AC) and MUC-6 were 100%, 81%, 77% and 85% with specificities of 27%, 100%, 87% and 87% for AC. CONCLUSION: We demonstrated that a two-marker panel of p40 and CDX2 is highly sensitive and specific.

Prognostic significance of CDX2 immunoexpression in poorly differentiated clusters of colorectal carcinoma.

CDX2 is a transcription factor that acts as a tumor suppressor in colorectal cancer (CRC). Its loss triggers metastatic process and tumor progression; however, its prognostic role in patients with CRC is still controversial. Poorly differentiated clusters (PDCs) are aggregates of neoplastic cells which likely have high metastatic potential in CRC. In this study, we analyzed and compared CDX2 expression in PDC (CDX2-PDC) and corresponding main tumor (CDX2 main tumor) in 42 CRCs showing at least 10 PDC (PDC G3). Five of 42 CRCs (12%) were classified as CDX2 main tumor negative (4/5 were also PDC-CDX2 negative); all had tumor recurrence and died of CRC. Twenty nine of 42 cases were CDX2-PDC negative. Among CRC CDX2 main tumor positive, 15 had recurrences and 13 died from CRC; 13 and 11 of them, respectively, were CDX2-PDC negative. By assigning one point to CDX2 main tumor or CDX2-PDC positivity, we assessed CDX2-staining score for each case. Twelve cases had CDX2-staining score 2 (CDX2 positive in main tumor and PDC); 26 had score 1 (CDX2 positive in main tumor or PDC), and 4 had CDX2 score 0 (CDX2 negative in main tumor and PDC). In our patients, CDX2-staining score had higher prognostic value compared to CDX2 main tumor or CDX2-PDC alone. In addition, it represented a significant and independent prognostic variable for disease-free survival (DFS) and cancer-specific survival (CSS). Our findings suggest that, although loss of CDX2 in the main tumor identifies high-risk patients with high specificity, CDX2-PDC should also be considered in CDX2 main tumor positive cases to predict prognosis.