Epithelial-mesenchymal transition (EMT) protein expression in a cohort of stage II colorectal cancer patients with characterized tumor budding and mismatch repair protein status

Grades of Poorly Differentiated Clusters are Associated with Lymph Node and the Tumour, Node and Metastasis Stages in Colorectal Carcinoma

Background

Colorectal carcinoma (CRC) is the third most common cancer globally. In Malaysia, CRC is most prevalent among males and the second most common cancer among females. The CRC arises mainly from the adenocarcinoma sequence. Poorly differentiated clusters (PDCs) and tumour budding (TB) are believed to represent sequential steps in tumour growth. Therefore, this study analysed the association between PDC grades with clinicopathological and demographic characteristics of CRC.

Methods

A total of 47 CRC cases previously diagnosed by histopathological examination were reviewed for the presence of PDCs and graded accordingly. The association between PDC grades with clinicopathological and demographic characteristics was statistically analysed.

Results

Out of the 47 cases with PDCs, most of them were of grade 3 (G3) (n = 27, 57.4%), followed by grade 2 (G2) (n = 13, 27.7%) and grade 1 (G1) (n = 7, 14.9%). Higher PDC grades (G2 and G3) were mainly observed in higher tumour stage (T); T3 (n = 26, 83.9%), T4 (n = 12, 92.3%), N1 (n = 20, 86.9%), N2 (n = 15, 100%). In addition, there was a significant association between PDC grades with the nodal stage (N) (P = 0.013) and the tumour, node and metastasis (TNM) stages (P = 0.012).

Conclusion

The PDC grades are useful for assessing the disease prognosis in CRC. A statistically significant association between PDC grades with N and TNM stages suggested that PDC grades are potential predictive parameters for invasive and metastatic risks in CRC.

Prognostic Value of Tumor Budding for Early Breast Cancer

BACKGROUND

Tumor budding (TB) is a dynamic process associated with the epithelial-mesenchymal transition and a well-established prognostic biomarker for colorectal cancer. As part of the tumor microenvironment, tumor buds demonstrate increased cell motility and invasiveness. Current evidence demonstrates that high levels of TB correlate with disease progression and worst outcomes across different solid tumors. Our work aims to demonstrate the clinical applicability of TB analysis and its utility as a prognostic factor for patients with early breast cancer (EBC).

METHODS

Retrospective, single-center, observational study, enrolling patients with EBC diagnosed in a Portuguese hospital between 2014 and 2015. TB classification was performed according to the International Tumor Budding Conference 2016 guidelines.

RESULTS

A statistically significant relation was found between higher TB score and aggressive clinicopathological features (angiolymphatic/perineural invasion-p < 0.001; tumor size-p = 0.012; nuclear grading-p < 0.001; and Ki-67 index-p = 0.011), higher number of relapses (p < 0.001), and short disease-free survival (DFS) (p < 0.001).

CONCLUSION

We demonstrate that high TB correlates with shorter DFS and aggressive clinicopathological features used in daily practice to decide on the benefit of chemotherapy for EBC. TB represents a needed prognostic biomarker for EBC, comprising a new factor to be considered in the adjuvant decision-making process by identifying patients at a high risk of relapse and with higher benefit on treatment intensification. Clinical trials incorporating TB are needed to validate its prognostic impact.

Tumor budding as a potential prognostic marker in determining the behavior of primary liver cancers

Hepatocellular (HCC) and intrahepatic cholangiocarcinoma (ICC), the most common primary tumors of the liver, are among the most important causes of cancer deaths worldwide. Because patients with primary liver tumors are frequently diagnosed at an advanced stage and have high mortality, many efforts have been made to identify new markers to determine their behavior and treatment, similar to those in other solid organ tumors. Recently, morphological assessment of tumor budding (TB) has been revealed as a promising prognostic finding to predict tumor behavior and survival across several different tumor types. Currently, the TB score in colorectal cancer has been revealed as an important parameter in pathology report protocols to determine the course of the disease. Regarding the liver, despite enormous data showing that many mechanisms involved in TB are associated with tumor behavior in both HCC and ICC, studies focusing on the role of TB in predicting the behavior and prognosis of these tumors have started to be investigated very recently. The purpose of this review is to present data about TB in primary tumors of the liver, pointing out the potential role of this parameter in determining the course of the disease, and emphasize the need to increase the number of further studies focusing on the evaluation of this parameter with an overview of the mechanisms involved in TB.

Prognostic impact of tumour budding in squamous cell carcinoma of the lung: a systematic review and meta-analysis

Tumour budding is an established prognostic factor in various solid tumours, including colorectal cancers and oral squamous cell carcinomas. However, its role is unclear and needs to be defined for squamous cell carcinoma of the lung (LSCC). Hence, we conducted a systematic review and meta-analysis investigating the prognostic role of tumour budding in LSCC. PubMed, Embase and Scopus were searched for peer-reviewed literature investigating the association between tumour budding and survival outcomes or clinicopathological variables in LSCC. The primary outcomes were pooled estimates for overall and recurrence-free survival with hazard ratio (HR) as the effect measure. The association between tumour budding and clinicopathological parameters was also investigated. Of 243 studies, nine were included, comprising 2546 patients. An increased risk of death [HR = 1.76, 95% confidence interval (CI) = 1.50-2.05, P < 0.00001] and recurrence (HR = 1.37, 95% CI = 1.12-1.68, P = 0.003) was evident in patients with high-grade tumour budding. Sensitivity and subgroup analyses revealed consistent results. Pathological stage II, lymph node metastasis, lymphovascular and pleural invasion were associated with high-grade tumour budding. Tumour budding is a new and promising prognostic factor in patients with LSCC. However, pervasive heterogeneity and publication bias reduces the credibility of these findings and the applicability of tumour budding in clinical practice. Future studies are required to standardise reporting on tumour budding in LSCC.

Impact of microsatellite status in early-onset colonic cancer

BACKGROUND

The molecular profile of early-onset colonic cancer is undefined. This study evaluated clinicopathological features and oncological outcomes of young patients with colonic cancer according to microsatellite status.

METHODS

Anonymized data from an international collaboration were analysed. Criteria for inclusion were patients younger than 50 years diagnosed with stage I-III colonic cancer that was surgically resected. Clinicopathological features, microsatellite status, and disease-specific outcomes were evaluated.

RESULTS

A total of 650 patients fulfilled the criteria for inclusion. Microsatellite instability (MSI) was identified in 170 (26.2 per cent), whereas 480 had microsatellite-stable (MSS) tumours (relative risk of MSI 2.5 compared with older patients). MSI was associated with a family history of colorectal cancer and lesions in the proximal colon. The proportions with pathological node-positive disease (45.9 versus 45.6 per cent; P = 1.000) and tumour budding (20.3 versus 20.5 per cent; P = 1.000) were similar in the two groups. Patients with MSI tumours were more likely to have BRAF (22.5 versus 6.9 per cent; P < 0.001) and KRAS (40.0 versus 24.2 per cent; P = 0.006) mutations, and a hereditary cancer syndrome (30.0 versus 5.0 per cent; P < 0.001; relative risk 6). Five-year disease-free survival rates in the MSI group were 95.0, 92.0, and 80.0 per cent for patients with stage I, II, and III tumours, compared with 88.0, 88.0, and 65.0 per cent in the MSS group (P = 0.753, P = 0.487, and P = 0.105 respectively).

CONCLUSION

Patients with early-onset colonic cancer have a high risk of MSI and defined genetic conditions. Those with MSI tumours have more adverse pathology (budding, KRAS/BRAF mutations, and nodal metastases) than older patients with MSI cancers.

Systematic review of tumour budding and association with common mutations in patients with colorectal cancer

INTRODUCTION

Despite a well-known prognostic role in colorectal cancer, the genomic profiling of tumour budding remains to be elucidated. We aim to review the association of common mutations with tumour budding.

METHODS

A systematic review of studies relating to tumour budding and genetic mutation in CRC was performed. The relationship between mutational status and tumour budding was evaluated using meta-analysis.

RESULTS

A total of 6153 patients from 17 articles were included. According to the meta-analysis, high-grade tumour budding was significantly associated with KRAS mutation (OR = 1.52, 95 %CI: 1.13-2.02, P = 0.005) and MSS/pMMR (OR = 2.06, 95 %CI: 1.42-2.97, P = 0.0001).

CONCLUSION

The significant association between high-grade tumour budding and mutated KRAS or MSS/pMMR may suggest a role of these mutations in the development of the tumour budding phenotype and be useful for stratifying patient outcome in CRC.

Rate of dissemination and prognosis in early and advanced stage colorectal cancer based on microsatellite instability status: systematic review and meta-analysis

INTRODUCTION

For the past two decades, microsatellite instability (MSI) has been reported as a robust clinical biomarker associated with survival advantage attributed to its immunogenicity. However, MSI is also associated with high-risk adverse pathological features (poorly differentiated, mucinous, signet cell, higher grade) and exhibits a double-edged sword phenomenon. We performed a systematic review and meta-analysis to evaluate the rate of dissemination and the prognosis of early and advanced stage colorectal cancer based on MSI status.

METHODS

A systematic literature search of original studies was performed on Ovid searching MEDLINE, Embase, Cochrane Database of Systematic Reviews, American College of Physicians ACP Journal Club, Database of Abstracts of Reviews of Effects DARE, Clinical Trials databases from inception of database to June 2019. Colorectal cancer, microsatellite instability, genomic instability and DNA mismatch repair were used as key words or MeSH terms. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed. Data were pooled using a random-effects model with odds ratio (OR) as the effect size. Statistical analysis was performed using RevMan ver 5.3 Cochrane Collaboration.

RESULTS

From 5288 studies, 136 met the inclusion criteria (n = 92,035; MSI-H 11,746 (13%)). Overall, MSI-H was associated with improved OS (OR, 0.81; 95% CI 0.73-0.90), DFS (OR, 0.73; 95% CI 0.66-0.81) and DSS (OR, 0.69; 95% CI 0.52-0.90). Importantly, MSI-H had a protective effect against dissemination with a significantly lower rate of lymph node and distant metastases. By stage, the protective effect of MSI-H in terms of OS and DFS was observed clearly in stage II and stage III. Survival in stage I CRC was excellent irrespective of MSI status. In stage IV CRC, without immunotherapy, MSI-H was not associated with any survival benefit.

CONCLUSIONS

MSI-H CRC was associated with an overall survival benefit with a lower rate of dissemination. Survival benefit was clearly evident in both stage II and III CRC, but MSI-H was neither a robust prognostic marker in stage I nor stage IV CRC without immunotherapy.

Cytoproliferative activity in colorectal poorly differentiated clusters: Biological significance in tumor setting

BACKGROUND

Poorly differentiated clusters (PDCs) have gained a significant prognostic role in colorectal carcinomas (CRCs) being associated to high risk of lymph node metastasis, shorter survival time and poor prognosis. The knowledge in PDC biology is not completely clear.

MATERIALS AND METHODS

We assessed Ki-67 LI in 45 CRCs showing ≥10 PDCs. We distinguished PDCs at the periphery of the tumor masses (pPDCs) from those within the tumor masses (cPDCs). We chose 3 cut-offs of Ki-67 labeling index (Ki-67 LI): <10%, 10-50%, and >50% of the labeled cells.

RESULTS

Ki-67 LI in pPDCs was<10% in 37 cases (82%), 10-50% in 6 cases (13%) and >50%in 2 cases (5%); Ki-67 LI in cPDCs was<10% in 4 cases (23.5%), 10-50% in 4 (23.5%) and >50% in 9 (54%). Ki-67 LI in tumor budding foci (TBs) was <10% in 8 cases (32%), 10-50% in 8 (32%) and >50% in 9 (36%). The difference of Ki-67 LI reaches the statistical significance (p < 0.005). Ki-67 LI <10% in the pPDCs was associated with nodal metastases (pN+) (p < 0.0001), pTNM stage III and IV(p < 0.0001) and TB (p < 0.001). Ki-67 LI > 50% in cPDC was significantly associated withpT3-pT4 and advanced pTNM stages (p < 0.0001), N+ (p = 0.0001) and LVI (p < 0.05).

CONCLUSION

Different Ki-67 LI detected between cPDCs and pPDCs suggesting a biological difference in PDCs. An actively proliferating central tumor areas can be distinguished from the peripheral portion of the tumors in which the cells interact with the stroma acquiring invasive and metastatic potential.

Intrahepatic Cholangiocarcinoma Cells Promote Epithelial-mesenchymal Transition of Hepatocellular Carcinoma Cells by Secreting LAMC2

Hepatocellular carcinoma and intrahepatic cholangiocarcinoma cells are common primary hepatic tumor cells in the liver. Combined hepatocellular cholangiocarcinoma (CHC) contains both hepatocellular carcinoma cells and intrahepatic cholangiocarcinoma cells in one tumor lesion and these tumors show poor prognosis. Here we examined the potential interaction between hepatocellular carcinoma cells and intrahepatic cholangiocarcinoma cells using cell culture studies. The results showed that culture supernatant from intrahepatic cholangiocarcinoma cells induced endothelial-mesenchymal transition and facilitated the migration and invasion of hepatocellular carcinoma cells, although it did not accelerate the proliferation of hepatocellular carcinoma cells. Furthermore, culture supernatant from intrahepatic cholangiocarcinoma cells increased the chemoresistance of hepatocellular carcinoma cells. Laminin subunit gamma 2 (LAMC2) was detected in the culture supernatant of intrahepatic cholangiocarcinoma cells but not in that of hepatocellular carcinoma cells. Using established LAMC2 knockout intrahepatic cholangiocarcinoma cells, our results demonstrated that intrahepatic cholangiocarcinoma cells promoted the epithelial-mesenchymal transition of hepatocellular carcinoma cells through secreting LAMC2. Our results have revealed a novel mechanism of interaction between intrahepatic cholangiocarcinoma cells and hepatocellular carcinoma cells, which may provide new insight into developing effective treatments for CHC.

Increasing tumor budding in cholangiocarcinoma is associated with decreased disease-specific survival

Tumor budding (TB) has been shown to be an adverse prognostic factor in several gastrointestinal malignancies, most notably colorectal carcinoma (CRC). TB has undergone some evaluation in Eastern cohorts of cholangiocarcinoma (CC), and we undertook this study to evaluate whether TB in CC was linked to other clinicopathologic factors or to outcome in a Western cohort. We evaluated 112 cases of CC for age, sex, margin status, location, size, grade, lymphovascular invasion (LVI), perineural invasion (PNI), subtype (large or small duct), staging parameters, recurrence-free survival, disease-specific survival (DSS), and TB. Budding was scored using International Tumor Budding Consensus Conference recommendations for CRC: The highest tumor bud count at the invasive tumor front in a 0.785 mm² area was recorded and stratified into Bd1 (0-4 buds), Bd2 (5-9 buds), and Bd3 (≥10 buds). Our cohort included 54 (48%) extrahepatic CCs and 58 (52%) intrahepatic CCs. TB was more commonly seen in the settings of higher-grade lesions, males, extrahepatic CC, PNI, LVI, and positive resection margin (all P ≤ 0.021). In multivariate analysis, worse DSS was correlated with budding score Bd2/Bd3 (hazard ratio [HR] 2.6687, 95% confidence interval [CI] 1.585-5.217, P = 0.001) and with nodal disease (HR 2.876, 95% CI 1.585-5.217, P = 0.001). TB is associated with higher-grade disease in CC, and increased TB is associated with poor disease-specific survival. Our findings support the notion that TB may serve as useful information for clinicians with respect to patient prognosis in CC, as in CRC.

Lymph Node Tumor Burden Correlates With Tumor Budding and Poorly Differentiated Clusters: A New Prognostic Factor in Colorectal Carcinoma?

INTRODUCTION

Molecular lymph node (LN) staging in early colorectal cancer (CRC) has demonstrated to be more precise than conventional histopathology pN staging. Tumor budding (TB) and poorly differentiated clusters (PDCs) are associated with LN metastases, recurrences, and lower survival in CRC. We evaluated the correlation between the total tumor load (TTL) in LNs from CRC surgical specimens with patient outcome, TB, and PDC.

METHODS

In this retrospective multicentre study, 5,931 LNs from 342 stage I-III CRC were analyzed by both hematoxylin and eosin and molecular detection of tumor cytokeratin 19 mRNA by one-step nucleic acid amplification. TB and PDC were evaluated by hematoxylin and eosin and cytokeratin 19 immunohistochemistry.

RESULTS

One-step nucleic acid was positive in 38.3% patients (n = 131). Tumor Budding was low in 45% cases, intermediate in 25%, and high in 30%. Poorly Differentiated Clusters were low-grade G1 in 53%, G2 in 32%, and G3 in 15%. TB and PDC correlated with TTL, high-grade, lymphovascular and perineural invasion, pT, pN and stage (P < 0.001). TB, PDC, and TTL ≥ 6,000 copies/µL were associated with worse overall survival (P = 0.002, P = 0.013, and P = 0.046) and disease-free survival (P < 0.001).

DISCUSSION

The implementation of more sensitive molecular methods to assess LN status is a promising alternative approach to pN staging, which could be integrated to other factors to help risk stratification and management of patients with early-stage CRC. This study demonstrates the correlation of the amount of LN tumor burden with TB and PDCs. TTL is related to the outcome and could be used as a new prognostic factor in CRC (see Visual Abstract, Supplementary Digital Content 2, http://links.lww.com/CTG/A512).

Tumor budding in upper urinary tract urothelial carcinoma: a putative prognostic factor for extraurothelial recurrence and overall survival

Tumor budding, defined as a single cancer cell or clusters of fewer than five cancer cells observed at the tumor invasion front, has been reported to be associated with poor prognosis in various types of cancers. However, limited information regarding the pathological and prognostic significance of tumor budding in upper urinary tract urothelial carcinoma (UUTUC) is available. We investigated 135 consecutive patients with newly diagnosed invasive UUTUCs (73 with renal pelvic cancers and 62 with ureteral cancers) treated with nephroureterectomy or partial ureterectomy between 1999 and 2018 in our hospital. Under a × 200 magnification, tumors with 10 or more budding foci were defined as "high tumor budding". The median follow-up period was 53.6 months. Among the 135 patients, 41 (30%; 16 with renal pelvic cancers and 25 with ureteral cancers) showed high tumor budding. High tumor budding was related to adjuvant chemotherapy status, higher pathological T stage, lymphovascular invasion, lymph node metastasis, tumor location, concomitant variant histology, and non-papillary gross finding. The multivariate Cox analysis revealed that LVI and high tumor budding were independent predictors for extraurothelial recurrence (P = 0.039 and 0.014, hazard ratio = 2.50 and 2.88, respectively), and high tumor budding was an independent predictor for overall survival (P = 0.024, hazard ratio = 2.33). Tumor budding can be easily introduced in clinical practice with no need for immunohistochemical analysis, may be an important clinicopathological factor of UUTUC, and is suggested to be useful as a novel predictive prognostic factor of patients with invasive UUTUC.

Physiological Roles of ERM Proteins and Transcriptional Regulators in Supporting Membrane Expression of Efflux Transporters as Factors of Drug Resistance in Cancer

One factor contributing to the malignancy of cancer cells is the acquisition of drug resistance during chemotherapy via increased expression of efflux transporters, such as P-glycoprotein (P-gp), multidrug resistance-associated proteins (MRPs), and breast cancer resistance protein (BCRP). These transporters operate at the cell membrane, and are anchored in place by the scaffold proteins ezrin (Ezr), radixin (Rdx), and moesin (Msn) (ERM proteins), which regulate their functional activity. The identity of the regulatory scaffold protein(s) differs depending upon the transporter, and also upon the tissue in which it is expressed, even for the same transporter. Another factor contributing to malignancy is metastatic ability. Epithelial-mesenchymal transition (EMT) is the first step in the conversion of primary epithelial cells into mesenchymal cells that can be transported to other organs via the blood. The SNAI family of transcriptional regulators triggers EMT, and SNAI expression is used is an indicator of malignancy. Furthermore, EMT has been suggested to be involved in drug resistance, since drug excretion from cancer cells is promoted during EMT. We showed recently that ERM proteins are induced by a member of the SNAI family, Snail. Here, we first review recent progress in research on the relationship between efflux transporters and scaffold proteins, including the question of tissue specificity. In the second part, we review the relationship between ERM scaffold proteins and the transcriptional regulatory factors that induce their expression.

Tumour budding in solid cancers

Tumour budding is an emerging prognostic biomarker in colorectal cancer (CRC) and other solid cancers. Tumour buds are usually defined as isolated single cancer cells or clusters of up to four cancer cells located at the invasive tumour front. The prognostic value of tumour budding is now supported by a large body of evidence, whereas the utility of this phenotype as a predictive biomarker remains under investigation. The application of tumour budding indices in clinical practice requires a standardized scoring system that can be tailored to specific tumour types and clinical scenarios. In the context of CRC, tumour budding can be assessed according to the method agreed at the International Tumour Budding Consensus Conference (ITBCC) in 2016. Using the ITBCC scoring system, tumour budding is an independent predictor of lymph node metastasis in patients with pT1 CRC and of unfavourable survival in patients with stage II colon cancer. Regardless of the clinical scenario or tumour type, the assertion that 'the more tumour buds, the worse the clinical outcome' applies. In this Review, we provide an overview of tumour budding in solid cancers, highlighting the molecular and biological aspects of this phenomenon, including its associations with epithelial-mesenchymal transition and features of the tumour microenvironment. We also describe the available evidence demonstrating the value of tumour budding as a biomarker across various solid cancers.

Clinical Significance of a Gene Signature Generated from Tumor Budding Grade in Colon Cancer

BACKGROUND

Tumor budding, a microscopic finding of dedifferentiation at the invasive margin, has been reported as a definite prognostic marker in colon cancer (CC). Herein, we aimed to generate a molecular budding signature (MBS) based on DNA microarray data and to examine its prognostic significance.

METHODS

Frozen tissue samples from 85 patients with stage II/III CC were used for DNA microarray analyses. First, we selected candidate genes that were differentially expressed (twofold change) between the invasive frontal regions and corresponding tumor centers of three extremely high-grade budding tumors. Subsequently, using microarray data from whole-tissue sections of the 85 patients, we selected MBS-constituent genes from the candidates based on correlation to the pathological budding grade. The MBS score was calculated using the sum of the logarithm of the expression of each gene.

RESULTS

We selected seven MBS-constituent genes: MSLN, SLC4A11, WNT11, SCEL, RUNX2, MGAT3, FOXC1. A comparison of relapse-free survival (RFS) rates revealed a significant impact of the MBS score [5-year RFS, 77.4% (score-high) vs. 95.1% (score-low); P = 0.044]. Analyses of public databases revealed that low MBS score patients exhibited better prognosis than those with high-score cancers (GSE14333: 5-year RFS, 83.1% vs. 66.6%, P = 0.028; GSE39582: 5-year disease-free survival, 72.2% vs. 58.1%, P = 0.0005). Multivariate analysis revealed that the MBS score is an independent prognostic indicator in GSE39582 (hazard ratio, 1.611; P = 0.013).

CONCLUSIONS

We developed a new gene classification method, i.e., MBS, and demonstrated its clinical relevance as an indicator of high recurrence risk of CC.

Differential Survival Benefits of 5-Fluorouracil-Based Adjuvant Chemotherapy for Patients With Microsatellite-Stable Stage III Colorectal Cancer According to the Tumor Budding Status: A Retrospective Analysis

BACKGROUND

Recent research has established tumor budding as a prognostic factor and a possible histomorphologic reflection of epithelial-mesenchymal transition in colorectal cancer, highlighting the ability of cancer cells exhibiting epithelial-mesenchymal transition to resist chemotherapy.

OBJECTIVE

This study aimed to investigate the clinical benefits of adjuvant chemotherapy according to the tumor budding status in microsatellite-stable stage III colorectal cancer.

DESIGN

This was a retrospective study of 2 cohorts.

SETTINGS

The study was conducted at the National Defense Medical College in Japan.

PATIENTS

We reviewed 2 data sets of patients with microsatellite-stable stage III colorectal cancer with curatively intended surgery (R0) from 1999 to 2005 (first cohort; n = 203) and 2006 to 2012 (second cohort; n = 346). In both cohorts, 128 and 203 patients received 5-fluorouracil-based adjuvant chemotherapy and 75 and 143 patients did not.

MAIN OUTCOME MEASURES

We assessed the benefits of adjuvant chemotherapy according to the grades of tumor budding based on the cancer-specific survival.

RESULTS

In low-budding tumors, the chemotherapy group exhibited better cancer-specific survival than the surgery-alone group (first cohort, 93.1% vs 65.5%, p = 0.001; second cohort, 94.0% vs 76.0%, p < 0.0001). Conversely, the prognostic difference between the chemotherapy and surgery-alone groups was statistically insignificant in high-budding tumors (first cohort, 59.7% vs 52.4%, p = 0.57; second cohort, 83.1% vs 75.6%, p = 0.19). The multivariate analysis corroborated the benefits of adjuvant chemotherapy in low-budding tumors (first cohort, p = 0.002, HR = 0.28; second cohort, p < 0.0001, HR = 0.23) but not in high-budding tumors.

LIMITATIONS

Postoperative adjuvant chemotherapy and treatments for recurrence were not homogeneous, and the patient backgrounds differed between the chemotherapy and surgery alone groups.

CONCLUSIONS

The high-budding group demonstrated resistance to 5-fluorouracil-based chemotherapy, whereas the low-budding group exhibited significant survival benefits from adjuvant chemotherapy in stage III colorectal cancer. See Video Abstract at http://links.lww.com/DCR/B14. BENEFICIOS DE SUPERVIVENCIA DIFERENCIAL DE LA QUIMIOTERAPIA ADYUVANTE BASADA EN 5-FLUOROURACILO PARA PACIENTES CON CÁNCER COLORRECTAL EN ESTADIO III ESTABLE CON MICROSATÉLITE SEGÚN EL ESTADO DE BROTACIÓN DEL TUMOR: UN ANÁLISIS RETROSPECTIVO:: Investigaciones recientes han establecido la aparición de tumores como un factor pronóstico y una posible reflexión histomorfológica de la transición epitelial-mesenquimatosa en el cáncer colorrectal, destacando la capacidad de las células cancerosas que presentan una transición epitelio-mesenquimática para resistir la quimioterapia.El objetivo de este estudio es investigar los beneficios clínicos de la quimioterapia adyuvante según el estado de brotación del tumor en el cáncer colorrectal en estadio III estable con microsatélite.Este fue un estudio retrospectivo de dos cohortes.El estudio se realizó en la Escuela de Medicina de la Defensa Nacional de Japón.Revisamos dos conjuntos de datos de pacientes con cáncer colorrectal en estadio III estable con microsatélite con cirugía de intención curativa (R0) de 1999 a 2005 (primera cohorte; n = 203) y 2006 a 2012 (segunda cohorte; n = 346). En ambas cohortes, 128 y 203 pacientes recibieron quimioterapia adyuvante basada en 5-fluorouracilo y 75 y 143 pacientes no, respectivamente.Evaluamos los beneficios de la quimioterapia adyuvante de acuerdo con los grados de brotación del tumor en función de la supervivencia específica del cáncer.n los tumores con brotes bajos, el grupo de quimioterapia mostró una mejor supervivencia específica al cáncer que el grupo con cirugía sola (primera cohorte, 93.1% vs. 65.5%, p = 0.001; segunda cohorte, 94.0% vs. 76.0%, p < 0.0001). A la inversa, la diferencia pronóstica entre los grupos de quimioterapia y cirugía sola fue estadísticamente insignificante en los tumores de brotes elevados (primera cohorte, 59.7% vs. 52.4%, p = 0.57; segunda cohorte, 83.1% vs. 75.6%, p = 0.19). El análisis multivariado corroboró los beneficios de la quimioterapia adyuvante en los tumores de brotes bajos (primera cohorte, p = 0,002, índice de riesgo: 0,28; segundo cohorte, p <0,0001, índice de riesgo: 0,23) pero no en los tumores de alto brote.a quimioterapia adyuvante postoperatoria y los tratamientos para la recurrencia no fueron homogéneos, y los antecedentes de los pacientes difirieron entre los grupos de quimioterapia y cirugía sola.El grupo de alto brote demostró resistencia a la quimioterapia basada en 5-fluorouracilo, mientras que el grupo de bajo brote mostró beneficios significativos de supervivencia de la quimioterapia adyuvante en el cáncer colorrectal en estadio III. Vea el Resumen del Video en http://links.lww.com/DCR/B14.

Cytomorphological Characterization of Individual Metastatic Tumor Cells from Gastrointestinal Cancer Patient Lymph Nodes with Imaging Flow Cytometry

The presence or absence of tumor cells within patient lymph nodes is an important prognostic indicator in a number of cancer types and an essential element of the staging process. However, patients with the same pathological stage will not necessarily have the same outcome. Therefore, additional factors may aid in identifying patients at a greater risk of developing metastasis. In this proof of principle study, initially, spiked tumor cells in rat lymph nodes were used to mimic a node with a small cancer deposit. Next, human lymph nodes were obtained from cancer patients for morphological characterization. Nodes were dissociated with a manual tissue homogenizer and stained with fluorescent antibodies against CD45 and Pan-Cytokeratin and then imaging flow cytometry (AMNIS ImageStreamX Mark II) was performed. We show here that imaging flow cytometry can be used for the detection and characterization of small numbers of cancer cells in lymph nodes and we also demonstrate the phenotypical and morphological characterization of cancer cells in gastrointestinal cancer patient lymph nodes. When used in addition to conventional histological techniques, this high throughput detection of tumor cells in lymph nodes may offer additional information assisting in the staging process with therapeutic and prognostic applications.

The Impact of Long-term Exposure to Low Levels of Inorganic Arsenic on the Hypomethylation of SEPT9 Promoter in Epithelial-Mesenchymal Transformed Colorectal Cancer Cell Lines

Inorganic arsenicals are worldwide environmental contaminants that affect molecular characteristics in biological systems and lead to genomic and epigenomic instability as well as epithelial mesenchymal transition (EMT). In this study, we aimed to investigate whether low levels of sodium arsenite (iAsIII) can influence EMT and genomic instability through microsatellite analysis. We have also determined epigenomic instability by investigating the methylation status of SEPT9 tumor marker in colorectal cancer (CRC) cell lines, Caco2 and HCT116, which were treated with iAsIII to assess IC50s. Short-term and long-term exposure to low concentrations (1 µM and 0.1 µM) of iAsIII in two separate experiments was implemented to analyze EMT, microsatellite status and the methylation pattern of SEPT9 promoter. As expected, after 20 days of exposure to iAsIII, the expression of CDH1 was significantly decreased while the expression of CDH2, FIB1 and VIM was increased in Caco2 and HCT116, a finding that confirmed EMT induction. However, there was no detectable alteration in the size of microsatellites. As for the methylation pattern, SEPT9 promoter was hypomethylated as a result of long-term exposure to 0.1 µM iAsIII in Caco2. Long-term exposure of HCT116 to both concentrations could induce hypomethylation of SEPT9 promoter. Our findings indicate no linkage between EMT induction and microsatellite status in iAsIII-treated CRC cell lines. For the first time, the current study has shown that the induction of EMT by iAsIII is linked with SEPT9 promoter hypomethylation in Caco2 and HCT116 in a concentration- and time-dependent pattern.

Tumor Budding in Colorectal Carcinoma: Translating a Morphologic Score Into Clinically Meaningful Results

CONTEXT

- Tumor budding has received increasing recognition as an important independent prognostic factor in colorectal carcinoma. Prominent tumor budding in adenocarcinoma arising in a polyp has been shown to be a risk factor for lymph node involvement. The variability in methods used for evaluating tumor budding in different studies and lack of standardized guidelines have impeded routine inclusion of tumor budding in pathology reports. This changed last year with consensus guidelines based on the International Tumor Budding Consensus Conference (ITBCC). These guidelines have been included in the recent College of American Pathologists (CAPs) Colorectal Cancer Protocol. The consensus methodology will allow uniform reporting of this finding, but challenges in interpretation in the setting of intense inflammation, fibrosis, or gland fragmentation need to be addressed in future guidelines.

OBJECTIVE

- To provide a brief overview of the known clinical significance of tumor budding in colorectal carcinoma and discuss the practical aspects of its implementation on a routine basis.

DATA SOURCES

- English-language pathology literature.

CONCLUSIONS

- Tumor budding has been shown to be an independent prognostic marker in colorectal carcinomas and the routine reporting of tumor buds is now advocated by using the approach outlined by the ITBCC guidelines. Tumor budding is included in the CAP protocol as a recommended element. Presence of prominent tumor budding in an adenocarcinoma in a polyp may have implications for management, such as additional resection, while it serves as a prognostic factor in other settings.

Pathological risk factors for lymph node metastasis in patients with submucosal invasive colorectal carcinoma

Background

Risk grade assessment determines therapy in patients with submucosal invasive colorectal carcinoma (CRC). However, treatment decisions are often difficult due to a lack of consensus on which risk factors should be considered. We aimed to identify predictive risk factors for lymph node metastasis (LNM) in a large cohort of submucosal invasive CRC patients from China.

Patients and methods

Following collection of clinicopathological data and disease-free survival (DFS) rates from 290 patients who underwent radical intestinal resection with regional lymphadenectomy, we immunohistochemically assessed expression of DNA mismatch repair (MMR) proteins and p53. The correlation between clinicopathological parameters, MMR expression, p53 status, and LNM status was determined using chi-squared tests and logistic analysis. Receiver operator characteristic curve analysis was used to compare the predictive values. The DFS curves were plotted using the Kaplan-Meier method.

Results

LNM was detected in 15.5% of the cases (45/290 patients). Three pathological characteristics, high tumor differentiation grade, lymphovascular invasion (LVI), and tumor budding, were all positively related to LNM in univariate and multivariate analyses (P<0.05). MMR status did not correlate with either LNM or the pathological characteristics (P>0.05). Overexpression of p53 was associated with tumor budding status (P=0.036). With a negative predicative value of 0.92 and area under the curve of 0.76 (95% CI: 0.68-0.85), the combination of these three factors provided optimal predictive ability. Patients with all three risk factors had poorer DFS (P<0.001).

Conclusion

High tumor grade, LVI, and positive tumor budding serve as useful LNM predictors in submucosal invasive CRC.

Novel biomarkers for patient stratification in colorectal cancer: A review of definitions, emerging concepts, and data

Colorectal cancer (CRC) treatment has become more personalised, incorporating a combination of the individual patient risk assessment, gene testing, and chemotherapy with surgery for optimal care. The improvement of staging with high-resolution imaging has allowed more selective treatments, optimising survival outcomes. The next step is to identify biomarkers that can inform clinicians of expected prognosis and offer the most beneficial treatment, while reducing unnecessary morbidity for the patient. The search for biomarkers in CRC has been of significant interest, with questions remaining on their impact and applicability. The study of biomarkers can be broadly divided into metabolic, molecular, microRNA, epithelial-to-mesenchymal-transition (EMT), and imaging classes. Although numerous molecules have claimed to impact prognosis and treatment, their clinical application has been limited. Furthermore, routine testing of prognostic markers with no demonstrable influence on response to treatment is a questionable practice, as it increases cost and can adversely affect expectations of treatment. In this review we focus on recent developments and emerging biomarkers with potential utility for clinical translation in CRC. We examine and critically appraise novel imaging and molecular-based approaches; evaluate the promising array of microRNAs, analyze metabolic profiles, and highlight key findings for biomarker potential in the EMT pathway.

Tumour budding in rectal cancer. A comprehensive review

A unique and fundamental characteristic of malignant neoplastic cells is their ability to invade other tissues and metastasise. The first step in this process is the dissociation of some of these cells from the tumour invasion front, named tumour budding (TB). This phenomenon has become increasingly relevant in recent years due to its association with adverse clinicopathological characteristics and with the epithelial-mesenchymal transition. TB has been studied by mixing colon with rectal tumours, but it is clinically important to differentiate these types of tumours. A review in two databases without language restriction was performed from 1950 to 2017 about TB with an emphasis on rectal cancer. We present various aspects of TB, from its terminology and evaluation to its molecular aspects, through its clinical associations. TB is associated with adverse clinicopathological features, like lymphovascular invasion, lymph node metastasis, and decreased survival. More studies of the clinicopathological, molecular, and epidemiological characteristics of TB in rectal cancer are needed.

MicroRNA-200b is downregulated in colon cancer budding cells

Background

The microRNA-200 (miR-200) family acts as a major suppressor of epithelial-mesenchymal transition (EMT). Impaired miR-200 expression may lead to EMT initiation and eventually cancer dissemination. The presence of tumor budding cells (TBC) is associated with metastasis and poor prognosis, and molecular similarities to EMT indicate that these cells may reflect ongoing EMT. The aim of this study was to investigate the expression of miR-200b in budding cells of colon cancer and the relationship with the EMT-markers E-cadherin, β-catenin and laminin-5γ2.

Material & methods

MiR-200b was investigated by in situ hybridization in 58 cases of stage II (n = 36) and III colon (n = 22) cancers with tumor budding. Expression of E-cadherin, β-catenin and laminin-5γ2 was examined by immunohistochemistry. A multiplex fluorescence assay combining miR-200b with cytokeratin and laminin-5γ2 was employed on a subset of 16 samples.

Results

MiR-200b was downregulated in the TBC at the invasive front of 41 out of 58 (71%) cases. The decline was present in both mismatch satellite stable and instable adenocarcinomas. The majority of cases also showed loss of membranous E-cadherin and increased nuclear β-catenin in the TBC, while laminin-5γ2 expression was upregulated at the invasive front and in the tumor buds of approximately half the adenocarcinomas. However, the miR-200b decline was not statistically associated with the expression of any of the EMT-markers. The miR-200b decline was also documented by multiplex fluorescence. Fourteen out of fifteen cases showed a decrease in miR-200b expression in the majority of the TBC, but no obvious relationship between miR-200b and laminin-5γ2 expression was observed. Conclusion: The findings support the assumption of a miR-200b related downregulation in colon cancer budding cells. Whether miR-200b expression may be of clinical significance awaits further studies.

Loss of tumor suppressor Merlin results in aberrant activation of Wnt/β-catenin signaling in cancer

The expression of the tumor suppressor Merlin is compromised in nervous system malignancies due to genomic aberrations. We demonstrated for the first time, that in breast cancer, Merlin protein expression is lost due to proteasome-mediated elimination. Immunohistochemical analysis of tumor tissues from patients with metastatic breast cancer revealed characteristically reduced Merlin expression. Importantly, we identified a functional role for Merlin in impeding breast tumor xenograft growth and reducing invasive characteristics. We sought to determine a possible mechanism by which Merlin accomplishes this reduction in malignant activity. We observed that breast and pancreatic cancer cells with loss of Merlin show an aberrant increase in the activity of β-catenin concomitant with nuclear localization of β-catenin. We discovered that Merlin physically interacts with β-catenin, alters the sub-cellular localization of β-catenin, and significantly reduces the protein levels of β-catenin by targeting it for degradation through the upregulation of Axin1. Consequently, restoration of Merlin inhibited β-catenin-mediated transcriptional activity in breast and pancreatic cancer cells. We also present evidence that loss of Merlin sensitizes tumor cells to inhibition by compounds that target β-catenin-mediated activity. Thus, this study provides compelling evidence that Merlin reduces the malignant activity of pancreatic and breast cancer, in part by suppressing the Wnt/β-catenin pathway. Given the potent role of Wnt/β-catenin signaling in breast and pancreatic cancer and the flurry of activity to test β-catenin inhibitors in the clinic, our findings are opportune and provide evidence for Merlin in restraining aberrant activation of Wnt/β-catenin signaling.

E-CADHERIN EXPRESSION DOWNREGULATION ELEVATES TUMOROGENIC POTENTIAL OF HUMAN COLON CANCER CELL LINE HCT116 VIA INCREASE IN CANCER STEM CELLS AMOUNT

Introduction. E-cadherin aberrant expression or complete loss is common for a number of human malignant neoplasms, and can be a launching mechanism of an epithelial-mesenchymal transition. Passing through epithelial-mesenchymal transition could in turn promote to the acquisition of so called cancer stem cell phenotype by the transformed cells. The objective of the present study is to reveal the influence of E-cadherin expression level on the amount of cancer stem cells in human colon cancer cell line HCT116. Materials and methods. We have created cell sublines with E-cadherin up- and downregulation and assessed the percentage of cancer stem cells using tumor formation assay, clonogenic assay; we also evaluated profile of cell pluripotency markers. Results and conclusion. We have shown that the proportion of cancer stem cells in human colon adenocarcinoma cell line HCT116 depends on the E-cadherin expression level. E-cadherin expression downregulation results in elevated expression of pluripotency genes and in the increase of proportion of cancer stem cells via activation of Wnt/ß-signalling pathway. E-cadherin upregulation has a reverse effect and decreases the amount of HCT116 cancer stem cells. Thus, E-cadherin expression restoration seems prospective in colorectal anticancer therapy.

Systematic review and meta-analysis of the impact of tumour budding in colorectal cancer

Background:

Tumour budding is a histological finding in epithelial cancers indicating an unfavourable phenotype. Previous studies have demonstrated that it is a negative prognostic indicator in colorectal cancer (CRC), and has been proposed as an additional factor to incorporate into staging protocols.

Methods:

A systematic review of papers until March 2016 published on Embase, Medline, PubMed, PubMed Central and Cochrane databases pertaining to tumour budding in CRC was performed. Study end points were the presence of lymph node metastases, recurrence (local and distal) and 5-year cancer-related death.

Results:

A total of 7821 patients from 34 papers were included, with a mean rate of tumour budding of 36.8±16.5%. Pooled analysis suggested that specimens exhibiting tumour budding were significantly associated with lymph node positivity (OR 4.94, 95% CI 3.96–6.17, P<0.00001), more likely to develop disease recurrence over the time period (OR 5.50, 95% CI 3.64–8.29, P<0.00001) and more likely to lead to cancer-related death at 5 years (OR 4.51, 95% CI 2.55–7.99, P<0.00001).

Conclusions:

Tumour budding in CRC is strongly predictive of lymph node metastases, recurrence and cancer-related death at 5 years, and its incorporation into the CRC staging algorithm will contribute to more effective risk stratification.

Tumor budding, a novel prognostic indicator for predicting stage progression in T1 bladder cancers

Tumor budding has been defined as an isolated single cancer cell or a cluster composed of fewer than five cancer cells scattered in the stroma. It is a strong predictor for lymph node metastasis in T1 colorectal cancer. We introduced this concept to T1 non‐muscle invasive bladder cancer and evaluated whether tumor budding could have a prognostic impact on the clinical outcome. We identified 121 consecutive patients with newly diagnosed T1 bladder cancer between 1994 and 2014 at Keio University Hospital. All slides were re‐reviewed by a dedicated uropathologist. Budding foci were counted under ×200 magnification. When the number of budding foci was 10 or more, tumor budding was defined as positive. The relationship between tumor budding and clinical outcomes was assessed using a multivariate analysis. The median follow‐up was 52 months. Tumor budding was positive in 21 patients (17.4%). Tumor budding was significantly associated with T1 substaging, tumor architecture and lymphovascular invasion. The 5‐year progression‐free survival rate in T1 bladder cancer patients with tumor budding was 53.8%, which was significantly lower than that in patients without tumor budding (88.4%, P = 0.001). A multivariate Cox regression analysis revealed that tumor budding was independently associated with stage progression (P = 0.002, hazard ratio = 4.90). In a subgroup of patients treated with bacillus Calmette‐Guérin instillation (n = 88), tumor budding was also independently associated with stage progression (P = 0.003, hazard ratio = 5.65). Tumor budding may be a novel indicator for predicting stage progression in T1 bladder cancer, and would likely be easily introduced in clinical practice.

The relationship between tumour budding, the tumour microenvironment and survival in patients with primary operable colorectal cancer

Background:

Tumour budding has been reported to reflect invasiveness, metastasis and unfavourable prognosis in colorectal cancer. The aim of the study was to examine the relationship between tumour budding and clinicopathological characteristics, tumour microenvironment and survival in patients with primary operable colorectal cancer.

Methods:

A total of 303 patients from a prospective data set of patients with primary operable colorectal cancer were included in the study. The presence of budding was determined through assessment of all tumour-containing H&E slides and the number of tumour buds was counted using a 10 high-powered field method. Routine pathologic sections were used to assess: tumour necrosis, the tumour inflammatory cell infiltrate using Klintrup–Makinen (KM) grade and tumour stroma percentage (TSP) combined as the Glasgow Microenvironment Score (GMS).

Results:

High-grade tumour budding was present in 39% of all tumours and in 28% of node-negative tumours respectively. High-grade budding was significantly associated with T stage (P<0.001), N stage (P<0.001), TNM stage (P<0.001), serosal involvement (P<0.001), venous invasion (P<0.005), KM grade (P=0.022), high tumour stroma (P<0.001) and GMS (P<0.001). Tumour budding was associated with reduced cancer-specific survival (CSS) (HR=4.03; 95% confidence interval (CI), 2.50–6.52; P<0.001), independent of age (HR=1.47; 95% CI, 1.13–1.90; P=0.004), TNM stage (HR=1.52; 95% CI, 1.02–2.25; P=0.040), venous invasion (HR=1.73; 95% CI, 1.13–2.64; P=0.012) and GMS (HR=1.54; 95% CI, 1.15–2.07; P=0.004).

Conclusions:

The presence of tumour budding was associated with elements of the tumour microenvironment and was an independent adverse prognostic factor in patients with primary operable colorectal cancer. Specifically high tumour budding stratifies effectively the prognostic value of tumour stage, venous invasion and GMS. Taken together, tumour budding should be assessed routinely in patients with primary operable colorectal cancer.

Tumour Budding and Survival in Stage II Colorectal Cancer: a Systematic Review and Pooled Analysis

PURPOSE

Tumour budding is defined as the presence of isolated or small clusters of malignant cells at the invasive edge of the tumour. It is considered a negative prognostic factor in colorectal cancer (CRC) and is associated with a poor outcome and adverse pathological features. Here, we report a meta-analysis of the association of tumour budding and survival in stage II CRC patients.

METHODS

PubMed, EMBASE, Web of Science and SCOPUS were searched for studies that assessed the relationship between tumour budding and 5-year overall survival (OS) in stage II CRC patients. Published data were extracted and used to compute odds ratios (ORs) for death at 5 years and hazard ratios (HRs) for survival amongst patients with respect to the extent of tumour budding, using multivariate analysis. Data were pooled using the Mantel-Haenszel random effect model.

RESULTS

We analysed 12 studies that included a total of 1652 patients. High-grade budding was associated with worse OS at 5 years (OR for death, 6.25; 95 % confidence interval [CI], 4.04-9.67; P < 0.00001). The absolute difference in 5-year OS was -25 % (95 % CI, -18- - 33 %, P < 0.00001). It was particularly noteworthy that the presence of high-grade budding was associated with an increased risk of death (HR for death, 3.68; 95 % CI, 2.16-6.28, P < 0.00001).

CONCLUSIONS

Tumour budding is associated with worse survival in stage II CRC, in particular in pT3N0M0 patients. It could therefore potentially be used when deciding whether to administer adjuvant chemotherapy in high-risk node negative CRC patients.

Poorly differentiated clusters (PDC) in colorectal cancer: what is and ought to be known

Background

The counting of poorly differentiated clusters of 5 or more cancer cells lacking a gland-like structure in a tumor mass has recently been identified among the histological features predictive of poor prognosis in colorectal cancer.

Main body

Poorly differentiated clusters can easily be recognized in the histological sections of colorectal cancer routinely stained with haematoxylin and eosin. Despite some limitations related to specimen fragmentation, counting can also be assessed in endoscopic biopsies. Based on the number of poorly differentiated clusters that appear under a microscopic field of a ×20 objective lens (i.e., a microscopic field with a major axis of 1 mm), colorectal cancer can be graded into malignancies as follows: tumors with <5 clusters as grade 1, tumors with 5 to 9 clusters as grade 2, and tumors with ≥10 clusters as grade 3. High poorly differentiated cluster counts are significantly associated with peri-neural and lympho-vascular invasion, the presence of nodal metastases or micrometastases, as well as shorter overall and progression free survival to colorectal cancer.

Conclusion

The morphological aspects and clinical relevance of poorly differentiated clusters counting in colorectal cancer are discussed in this review.

Acquisition of Chemoresistance and Other Malignancy-related Features of Colorectal Cancer Cells Are Incremented by Ribosome-inactivating Stress

Colorectal cancer (CRC) as an environmental disease is largely influenced by accumulated epithelial stress from diverse environmental causes. We are exposed to ribosome-related insults, including ribosome-inactivating stress (RIS), from the environment, dietary factors, and medicines, but their physiological impacts on the chemotherapy of CRC are not yet understood. Here we revealed the effects of RIS on chemosensitivity and other malignancy-related properties of CRC cells. First, RIS led to bidirectional inhibition of p53-macrophage inhibitory cytokine 1 (MIC-1)-mediated death responses in response to anticancer drugs by either enhancing ATF3-linked antiapoptotic signaling or intrinsically inhibiting MIC-1 and p53 expression, regardless of ATF3. Second, RIS enhanced the epithelial-mesenchymal transition and biogenesis of cancer stem-like cells in an ATF3-dependent manner. These findings indicate that gastrointestinal exposure to RIS interferes with the efficacy of chemotherapeutics, mechanistically implying that ATF3-linked malignancy and chemoresistance can be novel therapeutic targets for the treatment of environmentally aggravated cancers.

Tumour budding in colorectal cancer: what do we know and what can we do?

Budding is a process during which individual or small clusters of up to five tumour cells detach from the main tumour mass and invade into the surrounding stroma. In colorectal cancer, this feature is observed in 20-40% of cases and is associated with lymphovascular invasion, lymph node and distant metastases, and poor prognosis. A variety of scoring systems for budding have been proposed but so far a gold standard is lacking, hampering implementation of a budding score in guidelines for pathological examination of colorectal cancer. Furthermore, little is known about the mechanisms which cause tumour cells to detach from the main tumour mass and obtain increased invasive potential. In this review, we present an overview of tumour budding including its definition, scoring systems, prognostic relevance and biological mechanisms involved.

Invasion Types Are Associated With Poor Prognosis in Lung Squamous Carcinoma Patients

Although the prognostic significance of the histologic patterns in lung adenocarcinoma is being identified, no significant prognostic indicators in lung squamous carcinoma are accepted as a standard universally. The aim of this study was to evaluate the histologic characteristics incorporating the defined invasion types and distinguish the features that can reflect prognosis.We reviewed all slices of 132 patients with lung squamous carcinoma. The cases were classified according to the World Health Organization (WHO) classification and were evaluated for tumor budding, single cell invasion, large cell invasion, cytologic atypia degree, mitotic count, number of buds, tumor nest size, fibrosis, and necrosis.In univariate analysis, overall survival was associated significantly with age (P = 0.023), lymph nodes metastasis (P < 0.001), distant organ metastasis (P < 0.001), pleural invasion (P < 0.001), tumor budding (P = 0.003), single cell invasion (P = 0.001), mitotic count (P < 0.001), and the cytologic atypia degree (P = 0.009). However, the subtypes of 2004 WHO classification showed no association with outcome (P = 0.209). In multivariate analysis, the independent significant prognostic indicators of lung squamous carcinoma were tumor budding (hazard ratio [HR] = 0.466, P = 0.005), single cell invasion (HR = 0.447, P = 0.003), mitotic count (HR = 0.502, P = 0.048) and cytologic atypia degree (HR = 0.479, P = 0.024).Lung squamous carcinomas with the invasion types were associated with a poor prognosis.

Tumor budding in colorectal cancer--ready for diagnostic practice?

Tumor budding is an important additional prognostic factor for patients with colorectal cancer (CRC). Defined as the presence of single tumor cells or small clusters of up to 5 cells in the tumor stroma, tumor budding has been likened to an epithelial-mesenchymal transition. Based on well-designed retrospective studies, tumor budding is linked to adverse outcome of CRC patients in 3 clinical scenarios: (1) in malignant polyps, detection of tumor buds is a risk factor for lymph node metastasis indicating the need for colorectal surgery; (2) tumor budding in stage II CRC is a highly adverse prognostic indicator and may aid patient selection for adjuvant therapy; (3) in the preoperative setting, presence of tumor budding in biopsy material may help to identify high-risk rectal cancer patients for neoadjuvant therapy. However, lack of consensus guidelines for standardized assessment still limits reporting in daily diagnostic practice. This article provides a practical and comprehensive overview on tumor budding aimed at the practicing pathologist. First, we review the prognostic value of tumor budding for the management of colon and rectal cancer patients. Second, we outline a practical, evidence-based proposal for the assessment of tumor budding in the daily sign-out. Last, we summarize the current knowledge of the molecular characteristics of high-grade budding tumors in the context of personalized treatment approaches and biomarker discovery.

Overexpression of RhoGDI2 correlates with the progression and prognosis of pancreatic carcinoma

Rho GDP dissociation inhibitor 2 (RhoGDI2) has been found to be a regulator of tumor metastasis. However, the expression of RhoGDI2 and its clinicopathological significance as well as the pathway of RhoGDI2 in tumor metastasis have yet to be investigated. To investigate the role of RhoGDI2 in the progression and prognosis of pancreatic carcinoma (PC), the expression of RhoGDI2 in human PC tissues was examined and compared with the clinicopathological characteristics and prognosis. Moreover, the relationship between RhoGDI2 and E-cadherin was examined. The results indicated that RhoGDI2 was overexpressed in PC tissues and associated with clinicopathological characteristics, including clinical stage and lymph node metastasis. Patients with a RhoGDI2‑negative expression had a significantly longer survival time than those with a RhoGDI2‑positive expression. Additionally, the expression of RhoGDI2 was negatively correlated with the expression of E-cadherin in PC tissues. Taken together, the findings suggest that RhoGDI2 is important in the progression and prognosis of PC, and may be used as a potential prognostic biomarker and a therapeutic target for PC.

Tumor budding in colorectal cancer revisited: results of a multicenter interobserver study

Tumor budding in colorectal cancer (CRC) is recognized as a valuable prognostic factor but its translation into daily histopathology practice has been delayed by lack of agreement on the optimal method of assessment. Within the context of the Swiss Association of Gastrointestinal Pathology (SAGIP), we performed a multicenter interobserver study on tumor budding, comparing hematoxylin and eosin (H&E) with pan-cytokeratin staining using a 10 high power field (10HPF) and hotspot (1HPF) method. Two serial sections of 50 TNM stage II-IV surgically treated CRC were stained for H&E and pan-cytokeratin. Tumor buds were scored by independent observers at six participating centers in Switzerland and Austria using the 10HPF and 1HPF method on a digital pathology platform. Pearson correlation (r) and intra-class correlation coefficients (ICC) comparing scores between centers were calculated. Three to four times more tumor buds were detected in pan-cytokeratin compared to H&E slides. Correlation coefficients for tumor budding counts between centers ranged from r = 0.46 to r = 0.91 for H&E and from r = 0.73 to r = 0.95 for pan-cytokeratin slides. Interobserver agreement across all centers was excellent for pan-cytokeratin [10HPF: ICC = 0.83 and 1HPF: ICC = 0.8]. In contrast, assessment of tumor budding on H&E slides reached only moderate agreement [10HPF: ICC = 0.58 and 1HPF: ICC = 0.49]. Based on previous literature and our findings, we recommend (1) pan-cytokeratin staining whenever possible, (2) 10HPF method for resection specimens, and (3) 1HPF method for limited material (preoperative biopsy or pT1). Since tumor budding counts can be used to determine probabilities of relevant outcomes and as such more optimally complement clinical decision making, we advocate the avoidance of cutoff scores.

Tumor budding in upper gastrointestinal carcinomas

The basis of personalized medicine in oncology is the prediction of an individual's risk of relapse and death from disease. The presence of tumor budding (TB) at the tumor-host interface of gastrointestinal cancers has been recognized as a hallmark of unfavorable disease biology. TB is defined as the presence of dedifferentiated cells or small clusters of up to five cells at the tumor invasive front and can be observed in aggressive carcinomas of the esophagus, stomach, pancreas, ampulla, colon, and rectum. Presence of TB reproducibly correlates with advanced tumor stage, frequent lymphovascular invasion, nodal, and distant metastasis. The UICC has officially recognized TB as additional independent prognostic factor in cancers of the colon and rectum. Recent studies have also characterized TB as a promising prognostic indicator for clinical management of esophageal squamous cell carcinoma, adenocarcinoma of the gastro-esophageal junction, and gastric adenocarcinoma. However, several important issues have to be addressed for application in daily diagnostic practice: (1) validation of prognostic scoring systems for TB in large, multi-center studies, (2) consensus on the optimal assessment method, and (3) inter-observer reproducibility. This review provides a comprehensive analysis of TB in cancers of the upper gastrointestinal tract including critical appraisal of perspectives for further study.

Identification of TNF-α-responsive promoters and enhancers in the intestinal epithelial cell model Caco-2

The Caco-2 cell line is one of the most important in vitro models for enterocytes, and is used to study drug absorption and disease, including inflammatory bowel disease and cancer. In order to use the model optimally, it is necessary to map its functional entities. In this study, we have generated genome-wide maps of active transcription start sites (TSSs), and active enhancers in Caco-2 cells with or without tumour necrosis factor (TNF)-α stimulation to mimic an inflammatory state. We found 520 promoters that significantly changed their usage level upon TNF-α stimulation; of these, 52% are not annotated. A subset of these has the potential to confer change in protein function due to protein domain exclusion. Moreover, we locate 890 transcribed enhancer candidates, where ∼50% are changing in usage after TNF-α stimulation. These enhancers share motif enrichments with similarly responding gene promoters. As a case example, we characterize an enhancer regulating the laminin-5 γ2-chain (LAMC2) gene by nuclear factor (NF)-κB binding. This report is the first to present comprehensive TSS and enhancer maps over Caco-2 cells, and highlights many novel inflammation-specific promoters and enhancers.

Clinical significance of epithelial-mesenchymal transition

The concept of epithelial-mesenchymal transition (EMT), a process where cells change their epithelial towards a mesenchymal phenotype, has gained overwhelming attention especially in the cancer research community. Thousands of scientific reports investigated changes in gene, mRNA and protein expression compatible with EMT and their possible correlation with tumor invasion, metastatic spread or patient prognosis; however, up to now, a proof of clinical significance of the concept is still missing. This review, with a main focus on the role of EMT in tumors, will summarize the basic molecular events underlying EMT including the signaling pathways capable of its induction as well as changes in EMT-associated protein expression and will very briefly touch the role of microRNAs in EMT. We then outline protein markers that are used most frequently for the assessment of EMT in research and diagnostic evaluation of tumor specimens and depict the link between EMT, a cancer stem cell (CSC) phenotype and resistance to conventional antineoplastic therapies. Furthermore, we evaluate a possible correlation between EMT marker expression and patient prognosis as well as current therapeutic concepts targeting the EMT process to slow down or prevent metastatic spread of malignant tumors.

The advantage of circulating tumor cells over serum carcinoembryonic antigen for predicting treatment responses in rectal cancer

AIM

The objective of this study was to investigate the clinical significance of circulating tumor cells (CTCs) on the evaluation and prediction of treatment responses in rectal cancer patients compared with serum carcinoembryonic antigen (CEA).

MATERIALS & METHODS

Both CTCs and CEA levels of 103 rectal cancer patients (66 with stage II-III and 37 with recurrence or metastasis) were analyzed before and after chemoradiotherapy. CTCs were detected using EpCAM magnetic bead-based enrichment combined with cytometric identification.

RESULTS

CTCs were detected in all patients while no tumor cells were found in healthy controls. CTC levels in metastatic patients were significantly higher than those with recurrence or stage II-III rectal cancer. There is a close relationship between CTC levels and treatment outcomes but serum CEA did not have any correlation.

CONCLUSION

CTCs are promising markers for the evaluation and prediction of treatment responses in rectal cancer patients, superior to the conventional tumor marker CEA.

Prognostic significance of tumor budding in rectal cancer biopsies before neoadjuvant therapy

Tumor budding is an increasingly important prognostic feature for pathologists to recognize. The aim of this study was to correlate intra-tumoral budding in pre-treatment rectal cancer biopsies with pathological response to neoadjuvant chemoradiotherapy and with long-term outcome. Data from a prospectively maintained database were acquired from patients with locally advanced rectal cancer who underwent neoadjuvant chemoradiotherapy. Pre-treatment rectal biopsies were retrospectively reviewed for evidence of intra-tumoral budding. Multivariate logistic regression was used to identify factors contributing to cancer-specific death, expressed as hazard ratios with 95% confidence intervals. Of the 185 patients with locally advanced rectal cancer, 89 patients met the eligibility criteria, of whom 18 (20%) exhibited budding in a pre-treatment tumor biopsy. Intra-tumoral budding predicted a poor pathological response to neoadjuvant chemoradiotherapy (higher ypT stage, P=0.032; lymph node involvement, P=0.018; lymphovascular invasion, P=0.004; and residual poorly differentiated tumors, P=0.005). No patient with intra-tumoral budding exhibited a tumor regression grade 1 or complete pathological response, providing a 100% specificity and positive predictive value for non-response to neoadjuvant chemoradiotherapy. Intra-tumoral budding was associated with a lower disease-free 5-year survival rate (33 vs 78%, P<0.001), cancer-specific 5-year survival rate (61 vs 87%, P=0.021) and predicted cancer-specific death (hazard ratio 3.51, 95% confidence interval 1.03-11.93, P=0.040). Intra-tumoral budding at diagnosis of rectal cancer identifies those who will poorly respond to neoadjuvant chemoradiotherapy and those with a poor prognosis.

Epithelial-to-mesenchymal transition in a fistula-associated anal adenocarcinoma in a patient with long-standing Crohn's disease

Anal adenocarcinomas arising from perianal fistulae represent a rare complication in Crohn's disease (CD) patients. We have previously demonstrated the involvement of an epithelial-to-mesenchymal transition (EMT) in the pathogenesis of CD-associated fistulae. Although EMT has also been implicated in the development of colorectal and anal carcinoma, the molecular link from fistula to carcinoma is unclear. We present a case of a 48-year-old White woman who developed a mucinous anal adenocarcinoma originating from a perianal, CD-associated fistula 24 years after being diagnosed with CD. To characterize the expression of EMT-associated molecules in fistula and carcinoma tissue, immunohistochemical analysis for Snail1, Slug, β-catenin and E-cadherin was performed. A mucinous anal adenocarcinoma developed on a perianal fistula in a patient with long-standing CD. After neoadjuvant radiochemotherapy, the fistula-associated tumour was resected and the patient is presently in remission. Using immunohistochemical analysis, we detected a remarkable staining of the Slug transcription factor in transitional cells lining the fistula tract. This observation is unique to this 'carcinoma'-fistula: we had previously shown Slug expression in cells surrounding the fistula tract but not in transitional cells. Expression of Snail1, β-catenin and E-cadherin in this case was comparable with our previous findings. We describe a rare case of a CD fistula-associated adenocarcinoma within an area of squamous epithelium of the perianal area and an unusual expression pattern of EMT markers in this fistula. This case seems to underline the relevance of our previous findings demonstrating that EMT plays an important role for fistula pathogenesis and likely carcinogenesis in CD patients.

The effects of shRNA-mediated gene silencing of transcription factor SNAI1 on the biological phenotypes of breast cancer cell line MCF-7

To research the effects of silencing transcription factor SNAI1 on the in vitro biological phenotypes of breast cancer cell line MCF-7, based on the gene sequence of SNAI1, we linked shRNA with the green fluorescent protein-expressing eukaryotic expression vector pGCsilencer™ U6/Neo/GFP, and transfected it into MCF-7 cells. The SNAI1 gene-silencing effect was authenticated by RT-PCR and immunofluorescence. We then examined the effect of gene silencing on the expression of epithelial and mesenchymal markers and on their biological phenotypes of the target cells. Finally, we explained that SNAI1 was bound to E-cadherin in MCF-7 cells by ChIP. Silencing SNAI1 upregulated the expression of epithelial markers claudin-4, claudin-7, and E-cadherin, while expression of the mesenchymal marker matrix metalloproteinase-2 was downregulated. The capacity for proliferation, migration, and invasion was diminished. SNAI1 binds to the E-cadherin gene promoter and inhibits its transcription. We can conclude that silencing gene SNAI1 inhibits expression of properties that are associated with the malignant phenotype of MCF-7 cells and reverses the epithelial-mesenchymal transition process by regulating relevant target gene E-cadherin.