High-incidence of PTEN mutations in Chinese patients with primary small cell carcinoma of the esophagus

Nomogram for the prediction of individualized overall survival of patients diagnosed with small cell esophageal carcinoma

Background

A nomogram was developed for the estimation of individualized overall survival (OS) of patients diagnosed with small cell esophageal carcinoma (SCEC).

Methods

From the SEER dataset, 427 patients diagnosed with SCEC during the period from 2004 to 2015 were selected as training sets. For the establishment of a nomogram capable of estimating the OS possibility of patients diagnosed with SCEC, a group of independent prognostic factors were identified and incorporated. The effectiveness of the nomogram was then both externally and internally verified among 159 patients from Fudan University Shanghai Cancer Center (FUSCC) who were diagnosed with SCEC between 2006 and 2015. The predictive accuracy and discriminative ability of the nomogram were measured by concordance index (C-index). Comparisons between nomogram and the AJCC staging systems (6th and 7th) were performed with calibration plots and area under the curves (AUC) values.

Results

We identified age, gender, primary site, SEER stage, surgery, radiotherapy, and chemotherapy as seven independent risk factors which were then used to set up the nomogram. Calibration curves indicated that the prediction of the nomogram was consistent with real observations for the possibilities of 1-, 3-, and 5-year OS, and applying the nomogram to the cohort for validation led to reproducible results. Moreover, the C-indices and AUC values were higher in the nomogram than those in the AJCC staging system AJCC which is also aimed at the prediction of OS.

Conclusions

This study resulted in the establishment of the first nomogram for the prediction of individualized OS of patients diagnosed with SCEC. The accuracy rate of prediction of this model may be higher than previously established staging systems.

Primary small cell carcinoma of the esophagus: progression in the last decade

Primary small cell carcinoma of the esophagus (PSCCE) is a highly malignant tumor that is diagnosed by endoscopic biopsy and immunohistochemistry. Because of its low incidence, a high degree of malignancy, and rapid progress, it is difficult to conduct large, randomized controlled trials and to establish a standard treatment plan for this disease. In recent years, several retrospective studies have been reported, and with the rise of emerging therapies, PSCCE has gradually become a focus of thoracic surgery. This paper reviews progress in the diagnosis and treatment of PSCCE in recent years.

A rare rarity: Neuroendocrine tumor of the esophagus

Esophageal Neuroendocrine tumors (NETs) are rare, aggressive and lacking specific symptoms. This causes a diagnostic delay, worsening the prognosis. Numerous cases are reported in literature, without a consensus on the management. Our aim was to clarify epidemiology, clinical presentation, diagnostic, therapeutic management of esophageal NETs. Extensive literature search identified a total of 226 articles. One hundred twenty-five articles (n = 1676) met the inclusion criteria, showing that: the incidence of esophageal NET varies geographically; men (60-70 years) are more affected; smoking and alcohol abuse are the major risk factors; dysphagia, weight loss, appetite loss are the most common clinical features. The histotypes include high-grade small and large cell esophageal carcinomas and low-grade carcinoid tumors. Mixed neuroendocrine/non-neuroendocrine neoplasms are the most common. Often the diagnosis occurs randomly on endoscopic examination. Circulating markers, functional combined with conventional imaging contributes to the diagnosis and management. Treatment depends on type, grade and stage of the tumor.

Integrated Genome-Wide Analysis of Gene Expression and DNA Copy Number Variations Highlights Stem Cell-Related Pathways in Small Cell Esophageal Carcinoma

Purpose/Objectives. Primary small cell esophageal carcinoma (SCEC) represents a rare and aggressive malignancy without any prospective clinical trial or established treatment strategy at present. Although previous studies have indicated similarities between SCEC and small cell lung cancer (SCLC) in terms of their clinical manifestations, pathology, and morphology, very little genetic information is available on this highly malignant tumor. At present, patients with SCEC are staged and treated according to the guidelines established for SCLC. However, early recurrence and distant metastasis are common, and long-time survivors are rare. Current options available for patients with relapsed SCEC are fairly unsatisfactory, and their prognosis is generally poor. Novel therapeutic approaches against SCEC are therefore urgently needed and require a deeper understanding of the underlying genetic mechanisms. The current investigation aims to characterize the gene expression profile and copy number variations (CNVs) in SCEC to clarify molecular markers and pathways that may possess clinical significance. Materials/Methods. De novo expression array was carried out on three matched sets of primary SCEC and adjacent normal tissue samples procured from the institutional tissue bank, utilizing the Affymetrix HG U133 Plus 2.0 Array. After individual tissue normalization, the statistical software GeneSpring GX 12.5 was used to determine differentially expressed genes (DEGs) in the tumors relative to their paired normal tissues. Gene enrichments in addition to functional annotation and gene interaction networks were performed using DAVID 6.8 and STRING 10.0, respectively. A gene alteration was determined to be recurrent if it was observed in at least 2 samples. Chromosomes X and Y were not included in calculations as gender differences are a known source of analysis bias. The DEGs of at least one SCEC sample could be mapped to the CNV regions (fold change (FC) ≥ 2 and false discovery rate (FDR) < 0.01) after gene expression profiling by RefSeq Transcript ID. These overlapped genes were subjected to the functional annotation using DAVID 6.8. In order to elucidate the effect of CNV on mRNA expression, we integrated the genome-wide copy number data and gene expression in 3 paired samples. CNV-associated gene expression aberration (CNV-FC) was calculated for the recurrent DEGs using previously published integrated microarray data as reference. Pearson's correlation coefficient was employed to determine if there was a statistical correlation between the gene expression log₂ ratios and their copy numbers using the SPSS 19.0 software. Genes that possessed CNV-FC ≥ 2 and r ≥ 0.6 (p < 0.05) were determined to be genes potentially associated with cancer. Results. High-quality DNA and total RNA were first extracted from both SCEC and normal tissues. Microarray data showed significant upregulation in WNT gene sets and downregulation in the PTEN and notch gene sets in SCEC. Functional annotation showed that genes associated with DNA replication, mitosis, cell cycle, DNA repair, telomere maintenance, RB, and p53 pathways were significantly altered in SCEC compared to corresponding noncancerous tissues (Benjamini p < 0.05). Thirteen recurrent CNVs were found in all SCEC samples by array CGH. Chromosomal regions with gain were located in 14q11.2, and regions with loss were located in 4q22.3-23.3, 3q25.31-q29, 5p15.31-15.2, 8q21.11-24.3, and 9p23-13.1 in all samples. In two samples, the 14q11.2-32.33 region was amplified, whereas 3p26.3-25.3, 4p16.3-11, 4q11-22.3, 4q23-25, 8p23.3, and 16p13.3 were deleted. We further identified 306 genes that consistently differed in copy number and expression (194 upregulated and 112 downregulated) between the SCEC and noncancerous tissues in all three samples. These genes were significantly enriched with those involved in cell cycle, mitosis, DNA repair, P53 pathway, and RB pathway, according to their functional annotation. These 306 DEGs also included network genes of the above pathways such as NUF2, CCNE2, NFIB, ETV5, KLF5, ATAD2, NDC80, and ZWINT. In addition, 39 individual DEGs demonstrated a minimum 2-fold copy number-associated expression change (median: 5.35, 95% CI: 4.53–16.98) and Pearson's correlation coefficient ≥ 0.6 (p < 0.05), of which PTP4A3 showed the highest correlation (CNV-FC = 21362.13; Pearson's correlation coefficient = 0.9983; p = 0.037). Two distinct groups of genes belonging to each SCEC and nonmalignant tissues were observed upon unsupervised two-way (genes and samples) hierarchical clustering. Conclusions. The current investigation is the first to produce data regarding the genomic signature of SCEC at the transcription level and in relation to CNVs. Our preliminary data indicate possible key roles of WNT and notch signaling in SCEC and overexpressed PTP4A3 as a potential therapeutic target. Further validation of our findings is warranted.

Primary neuroendocrine neoplasm of the esophagus - Report of 14 cases from a single institute and review of the literature

BACKGROUND:

Most prevalent esophageal neoplasm is squamous cell carcinoma and adenocarcinoma. Other tumors are uncommon and poorly studied. Primary neuroendocrine esophageal neoplasm is a rare carcinoma and most of its therapy management is based on lung neuroendocrine studies. Neuroendocrine tumors can be clustered in the following subtypes: high grade (small cell carcinoma or large cell carcinoma) and low grade (carcinoids).

OBJECTIVE:

The present study aims to assess clinical and pathological neuroendocrine esophageal tumors in a single oncologic center.

METHODS:

A retrospective analysis of patients and review of the literatures was performed.

RESULTS:

Fourteen patients were identified as neuroendocrine tumors, 11 male and 3 female patients. Mean age was 67.3 years old. Ten patients were classified as small cell, 3 as large cell and 1 as carcinoid. Four patients presented squamous cell carcinoma simultaneously and 1 also presented adenocarcinoma. Main sites of metastasis were liver, peritoneum, lung and bones. Most patients died before 2 years of follow-up. Patient with longer survival died at 35 months after diagnosis.

CONCLUSION:

Neuroendocrine esophageal tumors are rare; affect mainly men in their sixties or seventies. High grade tumors can be mixed to other subtypes neoplasms, such as adenocarcinoma and squamous cell carcinoma. Most of these patients have poor overall survival rates.

Dysregulation of PAK1 Is Associated with DNA Damage and Is of Prognostic Importance in Primary Esophageal Small Cell Carcinoma

Primary esophageal small cell carcinoma (PESCC) is a rare, but fatal subtype of esophageal carcinoma. No effective therapeutic regimen for it. P21-activated kinase 1 (PAK1) is known to function as an integrator and an indispensable node of major growth factor signaling and the molecular therapy targeting PAK1 has been clinical in pipeline. We thus set to examine the expression and clinical impact of PAK1 in PESCC. The expression of PAK1 was detected in a semi-quantitative manner by performing immunohistochemistry. PAK1 was overexpressed in 22 of 34 PESCC tumors, but in only 2 of 18 adjacent non-cancerous tissues. Overexpression of PAK1 was significantly associated with tumor location (p = 0.011), lymph node metastasis (p = 0.026) and patient survival (p = 0.032). We also investigated the association of PAK1 with DNA damage, a driven cause for malignancy progression. γH2AX, a DNA damage marker, was detectable in 18 of 24 (75.0%) cases, and PAK1 expression was associated with γH2AX (p = 0.027). Together, PAK1 is important in metastasis and progression of PESCC. The contribution of PAK1 to clinical outcomes may be involved in its regulating DNA damage pathway. Further studies are worth determining the potentials of PAK1 as prognostic indicator and therapeutic target for PESCC.

Neuroendocrine Carcinomas of the Gastroenteropancreatic System: A Comprehensive Review

To date, empirical literature has generally been considered lacking in relation to neuroendocrine carcinomas (NECs), the highly malignant subgroup of neuroendocrine neoplasms. NECs are often found in the lungs or the gastroenteropancreatic (GEP) system and can be of small or large cell type. Concentrating on GEP-NECs, we can conclude that survival times are poor, with a median of only 4–16 months depending on disease stage and primary site. Further, this aggressive disease appears to be on the rise, with incidence numbers increasing while survival times are stagnant. Treatment strategies concerning surgery are often undecided and second-line chemotherapy is not yet established. After an analysis of over 2600 articles, we can conclude that there is indeed more empirical literature concerning GEP-NECs available than previously assumed. This unique review is based on 333 selected articles and contains detailed information concerning all aspects of GEP-NECs. Namely, the classification, histology, genetic abnormalities, epidemiology, origin, biochemistry, imaging, treatment and survival of GEP-NECs are described. Also, organ-specific summaries with more detail in relation to disease presentation, diagnosis, treatment and survival are presented. Finally, key points are discussed with directions for future research priorities.

Real-time PCR detection chemistry

Real-time PCR is the method of choice in many laboratories for diagnostic and food applications. This technology merges the polymerase chain reaction chemistry with the use of fluorescent reporter molecules in order to monitor the production of amplification products during each cycle of the PCR reaction. Thus, the combination of excellent sensitivity and specificity, reproducible data, low contamination risk and reduced hand-on time, which make it a post-PCR analysis unnecessary, has made real-time PCR technology an appealing alternative to conventional PCR. The present paper attempts to provide a rigorous overview of fluorescent-based methods for nucleic acid analysis in real-time PCR described in the literature so far. Herein, different real-time PCR chemistries have been classified into two main groups; the first group comprises double-stranded DNA intercalating molecules, such as SYBR Green I and EvaGreen, whereas the second includes fluorophore-labeled oligonucleotides. The latter, in turn, has been divided into three subgroups according to the type of fluorescent molecules used in the PCR reaction: (i) primer-probes (Scorpions, Amplifluor, LUX, Cyclicons, Angler); (ii) probes; hydrolysis (TaqMan, MGB-TaqMan, Snake assay) and hybridization (Hybprobe or FRET, Molecular Beacons, HyBeacon, MGB-Pleiades, MGB-Eclipse, ResonSense, Yin-Yang or displacing); and (iii) analogues of nucleic acids (PNA, LNA, ZNA, non-natural bases: Plexor primer, Tiny-Molecular Beacon). In addition, structures, mechanisms of action, advantages and applications of such real-time PCR probes and analogues are depicted in this review.