Tumour budding and the expression of cancer stem cell marker aldehyde dehydrogenase 1 in nasopharyngeal carcinoma

Prostate cancer-associated transcript 6 (PCAT6) promotes epithelial-mesenchymal transition and stemness and worsens prognosis in patients with colorectal cancer

Approximately 20% of colorectal cancer (CRC) patients are first diagnosed with metastatic colorectal cancer (mCRC) because they develop symptoms at an advanced stage. Despite advancements in treatment, patients with metastatic disease still experience inferior survival rates. Our objective is to investigate the association between long noncoding RNAs (lncRNAs) and prognosis and to explore their role in mCRC. In this study, we find that elevated expression of PCAT6 is independently linked to unfavourable survival outcomes in The Cancer Genome Atlas (TCGA) data, and this finding is further confirmed in CRC samples obtained from Fudan University Shanghai Cancer Center. Cell lines and xenograft mouse models are used to examine the impact of PCAT6 on tumor metastasis. Knockdown of PCAT6 is observed to impede the metastatic phenotype of CRC, as evidenced by functional assays, demonstrating the suppression of epithelial-mesenchymal transition (EMT) and stemness. Our findings show the significance of PCAT6 in mCRC and its potential use as a prognostic biomarker.

Tumor budding is a prognostic factor in head and neck squamous cell carcinoma: A comprehensive meta-analysis and trial sequential analysis

BACKGROUND

Mortality is linked to tumor budding (TB) in certain neoplasms. TB as a relevant histopathological feature is conditioned by tumor site, a specific study on head and neck squamous cell carcinoma (HNSCC) is needed.

METHODS

A comprehensive meta-analysis was undertaken to investigate the relationship between TB and HNSCC-related outcomes.

RESULTS

Overall 42 studies were included. Patients harboring high TB reported an Overall Survival (OS) Hazard Ratio (HR) of 2.63 (95% confidential interval (CI) 2.04-3.39; p-value < 0.001), Disease-free Survival (DFS) HR of 1.88 (95%CI 1.57-2.24; p-value <0.001) and Disease-specific Survival (DSS) HR of 2.14 (95%CI 1.81-2.52; p-value <0.001). Lymph Node Metastasis (LNM) studies harbored null heterogeneity and marked association with TB (Odds Ratio (OR) = 4.48, 95%CI 2.97-6.76; p-value < 0.001). Trial Sequential Analysis (TSA) supported definitive results for DSS.

CONCLUSION

The study has provided compelling evidence that there is a significant association between TB and a worse prognosis for HNSCC.

Prognostic evaluation of tumour budding in oral squamous cell carcinoma: Evidenced by CD44 expression as a cancer stem cell marker

OBJECTIVES

Tumor budding is a sign of invasion and early step for metastasis of many cancers including oral squamous cell carcinoma (OSCC). Evidences suggest the presence of cancer stem cells in tumor buds. CD44 has been reported in tumor growth and metastasis as a cancer stem cell marker in OSCC. The study aims to highlight the prognostic significance of tumor budding in association with CD44 expression as a cancer stem cell marker in OSCC.

METHODS

A total of 60 radical neck dissection specimens of OSCC with and without lymph node metastasis were included in the study. The sections were evaluated for TB [Tumor Budding] in H&E and CD44 expression immunohistochemically. OSCC cases were then correlated with clinicopathologic and histomorphologic parameters such as age, gender, habit, site, staging, grading, recurrence, depth of invasion, pattern of invasion, and survival outcomes. Comparison of prognosis and CD44 expression were carried out by statistical methods.

RESULTS

A high TB score was significantly correlated with grading (p = 0.037), POI [Pattern of invasion] (0.029), overall survival (p = 0.047). CD44 over expression showed strong correlations with POI (1HPF:p = 0.037;10HPF:p = 0.027), grading (p = 0.037), and overall survival (p = 0.047). Kaplan-Meier analysis revealed overall survival advantage for LTB [Low TB] (85 %) with OSCC compare to HTB [High TB] (75 %) for > 36 months.

CONCLUSION

Assessment of TB is effective in predicting prognosis of OSCC. Although CD44 expression has demonstrated strong prognostic influence, there were significant differences in its expression with the parameters.

Predictive value of tumor budding in head and neck squamous cell carcinoma: an update

Head and neck squamous cell carcinoma forms an anatomically and functionally complex group of malignancies. The significant local aggressiveness and frequent regional relapses motivate ongoing research to identify more reliable and sensitive prognostic and predictive biomarkers. One emerging area of cancer biology is the evaluation of tumor budding at the advancing invasive front of various types of epithelial cancers. Recent studies suggest that tumor budding is a relatively common phenomenon in cancer progression and that it may have important prognostic implications for patients due to its potential to provide valuable insights into the biology and clinical behavior of head and neck cancer. In this review, we aim to provide information about tumor budding in head and neck squamous cell carcinoma. Thus, we hope to shed light on the complex biology of these malignancies, as well as aiding diagnostic, classification, and better characterization and thereby, looking for new avenues for improving patient outcomes.

Association between the expression levels of ADAMTS16 and BMP2 and tumor budding in hepatocellular carcinoma

Tumor budding (TB) has become a crucial factor for predicting the malignancy grade and prognostic outcome for multiple types of solid cancer. Studies have investigated the prognostic value of TB in hepatocellular carcinoma (HCC). However, its molecular mechanism in HCC remains unclear. To the best of our knowledge, the present study was the first to compare the expression of differentially expressed genes (DEGs) between TB-positive (TB-pos) and TB-negative HCC tissues. In the present study, total RNA was extracted from 40 HCC tissue specimens and then sequenced. According to Gene Ontology (GO) functional annotation, upregulated DEGs were markedly associated with embryonic kidney development-related GO terms, which suggested that the TB process may at least partly mimic the process of embryonic kidney development. Subsequently, two genes, a disintegrin and metalloproteinase domain with thrombospondin motifs 16 (ADAMTS16) and bone morphogenetic protein 2 (BMP2), were screened and verified through immunohistochemical analysis of HCC tissue microarrays. According to the immunohistochemical results, ADAMTS16 and BMP2 were upregulated in TB-pos HCC samples, and BMP2 expression was increased in budding cells compared with the tumor center. Additionally, through cell culture experiments, it was demonstrated that ADAMTS16 and BMP2 may promote TB of liver cancer, thus promoting the malignant progression of liver cancer. Further analysis revealed that ADAMTS16 expression was associated with necrosis and cholestasis, and BMP2 expression was associated with the Barcelona Clinic Liver Cancer stage and the vessels encapsulating tumor clusters. Overall, the findings of the present study provided insights into the possible mechanisms of TB in HCC and revealed potential anti-HCC therapeutic targets.

Relationship between Tumor Budding and Partial Epithelial-Mesenchymal Transition in Head and Neck Cancer

Tumor budding (TB), a microscopic finding in the stroma ahead of the invasive fronts of tumors, has been well investigated and reported as a prognostic marker in head and neck squamous cell carcinoma (HNSCC). Epithelial-mesenchymal transition (EMT) is a crucial step in tumor progression and metastasis, and its status cannot be distinguished from TB. The current understanding of partial EMT (p-EMT), the so-called halfway step of EMT, focuses on the tumor microenvironment (TME). Although this evidence has been investigated, the clinicopathological and biological relationship between TB and p-EMT remains debatable. At the invasion front, previous research suggested that cancer-associated fibroblasts (CAFs) are important for tumor progression, metastasis, p-EMT, and TB formation in the TME. Although there is biological evidence of TB drivers, no report has focused on their organized functional relationships. Understanding the mechanism of TB onset and the relationship between p-EMTs may facilitate the development of novel diagnostic and prognostic methods, and targeted therapies for the prevention of metastasis in epithelial cancer. Thus far, major pieces of evidence have been established from colorectal cancer (CRC), due to a large number of patients with the disease. Herein, we review the current understanding of p-EMT and TME dynamics and discuss the relationship between TB development and p-EMT, focusing on CAFs, hypoxia, tumor-associated macrophages, laminin-integrin crosstalk, membrane stiffness, enzymes, and viral infections in cancers, and clarify the gap of evidence between HNSCC and CRC.

The Emerging Impact of Tumor Budding in Oral Squamous Cell Carcinoma: Main Issues and Clinical Relevance of a New Prognostic Marker

Tumor Budding (TB) represents a single cancer cell or a small cluster of less than five cancer cells on the infiltrative tumor front. Accumulating evidence suggests TB is an independent prognostic factor in oral squamous cell carcinoma (OSCC). However, its exact role is not yet elucidated, and a standardized scoring system is still necessary. The study aims to extensively review the literature data regarding the prognostic role of TB in OSCC. The results of TB are an independent prognostic factor of poor survival outcomes in OSCC. To date, the manual detection of hematoxylin and eosin-staining or pancytokeratin-immunostaining sections are the most commonly used methods. Between the several cut-offs, the two-tier system with five buds/field cut-offs provides better risk stratification. The prognostic role of the BD model in predicting survival outcomes was extensively validated; however, the inclusion of DOI, which is already a staging parameter, encouraged other authors to propose other models, integrating TB count with other adverse risk factors, such as the tumor–stroma ratio and tumor-infiltrated lymphocytes. The prognostic relevance of TB in OSCC highlights its evaluation in daily pathological practice. Therefore, the TB detection method and the TB scoring system should be validated based on tumor stage and site.

Emerging histopathologic markers in early-stage oral tongue cancer: A systematic review and meta-analysis

Although there are many histopathologic prognosticators, grading of early oral tongue squamous cell carcinoma (OTSCC) is still based on morphological cell differentiation which has low prognostic value. Here we summarize the emerging histopathological markers showing powerful prognostic value, but are not included in pathology reports. Using PubMed, Scopus, Ovid Medline, and Web of Science databases, a systematic literature search was preformed to identify early OTSCC studies that investigated the prognostic significance of hematoxylin–eosin‐based histopathologic markers. Our meta‐analysis showed that tumor budding was associated with overall survival (hazard ratio [HR] 2.32; 95% CI 1.40–3.84; p < 0.01) and disease‐specific survival (DSS) (1.89; 95% CI 1.13–3.15; p = 0.02). Worst pattern of invasion was associated with disease‐free survival (DFS) (1.95; 95% CI 1.04–3.64; p = 0.04). Tumor–stroma ratio was also associated with DFS (1.75, 95% CI 1.24–2.48; p < 0.01) and DSS (1.69; 95% CI 1.19–2.42; p < 0.01). Tumor budding, worst pattern of invasion, and tumor–stroma ratio have a promising prognostic value in early OTSCC. The evaluation and reporting of these markers is cost‐effective and can be incorporated in daily practice.

Novel pathological predictive factors for extranodal extension in oral squamous cell carcinoma: a retrospective cohort study based on tumor budding, desmoplastic reaction, tumor-infiltrating lymphocytes, and depth of invasion

Background

Extranodal extension (ENE) is a poor prognostic factor for oral squamous cell carcinoma (OSCC). Identifying ENE by clinical and/or radiological examination is difficult, thereby leading to unnecessary neck dissections. Currently, no definitive predictors are available for ENE. Thus, we aimed to determine the histological predictors of ENE by routine histopathological examination using biopsy and surgically resected specimens.

Methods

This retrospective study included 186 surgically resected OSCC and 83 matched biopsy specimens. Clinical features associated with the tumor microenvironment, including desmoplastic reaction (DR), tumor budding (TB), and tumor-infiltrating lymphocytes (TILs), were evaluated using hematoxylin and eosin-stained primary OSCC and neck dissection specimens. These histological features were divided into two groups: DR-immature (DR-I) and DR-mature (DR-M); TB-high (TB-H) and TB-low (TB-L); and TILs-low (TILs-L) and TILs-high (TILs-H). Clinical depth of invasion (cDOI) and pathological DOI (pDOI) were adapted for biopsies and resections, respectively; DOI was evaluated as DOI > 10 mm and DOI ≤ 10 mm. The clinicopathological relationships between these histopathological features and ENE and the independent risk factors for ENE were analyzed. The histological predictors of ENE were evaluated.

Results

The histological status of DR, TILs, and TB present in biopsy and resection specimens showed high accuracy with that of ENE. DR-I, TILs-L, and TB-H were significantly associated with lymph node metastasis, cDOI, and pDOI. Bivariate and multivariate analyses revealed that TB-H and pDOI > 10 mm in resections were independent factors for the presence of ENE (ENE +). The combination of TB-H/pDOI > 10 mm in resection specimens showed high specificity (91%) and accuracy (83%) regarding ENE + . Although there proved to be no independent factors in biopsies, DR-I and TILs-L were significantly associated with ENE + (p < 0.001). The combination of DR-I/TILs-L/cDOI > 10 mm in biopsies exhibited high sensitivity and specificity with ENE + (70% and 77%, respectively, p < 0.001). These histological predictors could detect even minor ENE (< 2 mm).

Conclusions

The tumor microenvironment status in primary OSCC was significantly associated with that of ENE, and TB-H was an independent risk factor for ENE. The histological status of DR-I/TILs-L/cDOI > 10 mm in biopsy specimens and TB-H/pDOI > 10 mm in resection specimens is a useful predictor of ENE.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09393-8.

Stemness, Inflammation and Epithelial-Mesenchymal Transition in Colorectal Carcinoma: The Intricate Network

In global cancer statistics, colorectal carcinoma (CRC) ranks third by incidence and second by mortality, causing 10.0% of new cancer cases and 9.4% of oncological deaths worldwide. Despite the development of screening programs and preventive measures, there are still high numbers of advanced cases. Multiple problems compromise the treatment of metastatic colorectal cancer, one of these being cancer stem cells—a minor fraction of pluripotent, self-renewing malignant cells capable of maintaining steady, low proliferation and exhibiting an intriguing arsenal of treatment resistance mechanisms. Currently, there is an increasing body of evidence for intricate associations between inflammation, epithelial–mesenchymal transition and cancer stem cells. In this review, we focus on inflammation and its role in CRC stemness development through epithelial–mesenchymal transition.

Tumor Budding is a reliable predictor for death and metastasis in invasive ductal breast cancer and correlates with other prognostic clinicopathological parameters

BACKGROUND AND OBJECTIVE

Breast cancers are the most common type of cancer and the most common cause of mortality in women worldwide. Different prognostic factors are the subject of research to differentiate the prognosis even between cases at a similar stage and identify risky patients earlier and create individual treatment approaches. Tumor budding (TB) has been identified as a poor prognostic factor in many types of cancer, especially colorectal carcinomas. In our study, we aimed to determine the prognostic significance of the TB by evaluating the TB in line with clinicopathological parameters in breast invasive ductal carcinoma cases.

MATERIALS AND METHODS

311 breast carcinoma cases operated in our hospital between January 2010 and April 2020 were included in the study. In hematoxylin-eosin (H&E) sections of the cases, TB was evaluated in a single high-power field (HPF). ROC analysis was performed with overall survival data, and low, and high TB cutoffs were obtained. The relationship of the high TB with clinicopathological parameters was evaluated, and survival analysis was performed.

RESULTS

We determined that high TB in breast invasive ductal carcinoma cases was associated with low survival time, metastasis, axillary lymph node metastasis, angiolymphatic invasion, advanced stage (pT3), high Ki-67 proliferation index, progesterone receptor (PR) loss, and advanced age. Tumor budding was identified as an independent risk factor in overall and disease-free survival analysis.

CONCLUSION

Tumor budding is a prognostic parameter that can be easily evaluated in all centers since it does not cause additional cost to routine pathological examinations. We think it may be helpful to establish a standard methodology in evaluating tumor bud in breast carcinomas and including it in regular pathology reporting.

Clinicopathological correlation of stem cell markers expression in oral squamous cell carcinoma; relation to patients` outcome

Background: Squamous cell carcinoma (OSCC) is the commonest oral malignancy.The overall 5 year survival of OSCC has remained at 50%, largely unchanged for 40 years. CSCs are important within the development, invasion, drug resistance, and prediction of carcinomas treatment outcome. ALDH1 and CD44 are commonly used epithelial tumors cancer stem-like cells surface markers. Materials: Our study aimed to judge CD44 and ALDH1 immunohistochemical expressions in 44 cases of OSCC and relates the expression to patients' survival. Results: High CD44 & ALDH1 expressions were significantly expressed in variable histologic grades of OSCCs, large sized carcinomas, presence lymph vascular invasion, presence of nodal and distant metastasis, advanced TNM clinical stage, recurrence and death during follow up period (P ≤ 0.05). Reduced DFS and three years overall survival were significantly recorded in cases with high CD44 expression, and high ALDH1 expression (p < 0.05). CD44 & ALDH1 expressions, histologic grade, tumor size were the independent predictors of DFS and three years OS. Conclusion: CD44 and ALDH1 expressions are valuable prognostic factors in OSCC and could be well considered predictors for patients' 3 years OS and DFS.

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.

Tumor budding - A promising prognostic histopathological parameter in oral squamous cell carcinoma - A comparative immunohistochemical study

Introduction:

The majority of the head and neck squamous cell carcinomas (HNSCC) occur in the oral cavity. Even with advances in cancer therapy only minor improvements in the survival of HNSCC patients have taken place and approximately 350,000 patients die annually of HNSCC worldwide. Tumor budding (TB) is a novel and promising histo-morphological parameter that has been studied in many cancers. The presence of TB is associated with lymph node and distant metastasis as well as poor survival, independently of the applied scoring system. The depth of tumor invasion (D) measured from the surface of the tumor to the deepest point of invasion is also an important prognostic parameter for oral squamous cell carcinoma (OSCC) with a cutoff point of 4 mm. Both taken together constitute BD model and it has also been found to be an independent prognostic factor for patients with OSCC. Therefore, it would be highly beneficial to evaluate TB and BD model in routine histopathological reporting.

Aims and Objectives:

This study aims to compare the detection of TB in hematoxylin-eosin and pan-cytokeratin stained immune-histochemical sections of OSCC and also to evaluate whether BD score can serve as a reliable prognostic indicator for OSCC.

Methodology:

A total of 30 formalin-fixed, paraffin-embedded tissue blocks of clinically and histopathologically diagnosed cases of OSCC were retrieved. One section was stained with hematoxylin and eosin and the other was processed for pancytokeratin immunohistochemistry to evaluate tumor buds. Depth of invasion (D) was also evaluated to achieve the BD score.

Results:

Statistical significance (P < 0.001) was noted between TB score evaluated in hematoxylin and eosin (H&E) and pancytokeratin stained sections. There was no statistical significance between age, gender, site of lesion, clinical staging, survival and BD score.

Conclusion:

Immunohistochemical analysis of TB is superior to H&E staining in detection of tumor buds at the tumor invasive front.

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.

HN1 promotes tumor associated lymphangiogenesis and lymph node metastasis via NF-κB signaling activation in cervical carcinoma

Lymph node metastasis (LNM) is a critical cause for disease progression and treatment failure in cervical cancer. However, the mechanism underlying cervical cancer LNM remains unclear. In this study, HN1 was found to be dramatically upregulated in cervical cancer and patients with higher HN1 expression are more likely to exhibit a higher rate of LNM and lower survival rate. Univariate and multivariate Cox-regression analyses showed that HN1 is an independent prognostic factor in cervical cancer. Meanwhile, HN1 promotes lymphangiogenesis of cervical cancer in vitro. The in vivo experiment also indicates that HN1 enhances LNM in cervical cancer. Furthermore, we also found that HN1 activated the NF-κB signaling pathway to enhance the expression of downstream genes. Taken together, our study suggests that HN1 plays a crucial role in promoting LNM and acts as a prognostic biomarker in cervical cancer.

Different Expression of Aldehyde Dehydrogenases 1A1 and 2 in Oral Leukoplakia With Epithelial Dysplasia and in Oral Squamous Cell Carcinoma

Oral potentially malignant disorders (OPMD) may develop malignant characteristics and transform into oral squamous cell carcinoma (OSCC) in a range of 1% to 2% of cases. Chronic alcohol consumption is associated with carcinogenesis, but its mechanism has not yet been fully elucidated. ALDH1A1 and 2, isoenzymes responsible for aldehyde oxidation involved in ethanol metabolism may be associated with the development of malignant head and neck neoplasms. The aim of this study was to analyze the expression of ALDH1A1 and ALDH2 in oral leukoplakia with epithelial dysplasia (OLP) and OSCC. A retrospective study was conducted on 27 cases of OLP and 30 cases of OSCC. Clinical data were obtained from medical records, and all cases were classified as mild, moderate, and severe for OLP, and well-differentiated, moderately differentiated, or poorly differentiated for OSCC cases. The ALDH1A1 and ALDH2 expression in OLP and OSCC was evaluated by the immunohistochemical technique. There was predominance of the male sex, in both OLP and OSCC cases. Oral tongue was the most affected site in both groups. OLP showed positive protein expression of ALDH1A1 in all cases, both basal and suprabasal epithelial layers, whereas ALDH2 showed less protein expression. In OSCC, the immunohistochemical reaction for ALDH1A1 expression was negative in 70%, whereas ALDH2 expression was positive in all cases. This study demonstrated the gradual loss of ALDH1A1 expression in OSCC in comparison with OLP, and the increased ALDH2 expression in OSCC.

Tumor budding is an adverse prognostic marker in intestinal-type sinonasal adenocarcinoma and seems to be unrelated to epithelial-mesenchymal transition

Intestinal-type adenocarcinoma (ITAC) of sinonasal tract is a rare malignant tumor with strong morphological, immunophenotypical, and molecular similarities to colorectal adenocarcinoma (CRC). Tumor budding (TB) is a well-established adverse prognostic marker in CRC and some head and neck tumors, with features of epithelial-mesenchymal transition (EMT). The aim of this study was to assess TB in ITAC and to evaluate its possible association with EMT markers in this setting. We selected 32 surgically resected specimens of non-mucinous/non-signet ring ITAC and evaluated them for TB according to the international recommendations developed for CRC. The expression of the EMT markers E-cadherin, ZEB1, ZEB2, SLUG, and SNAIL was evaluated by immunohistochemistry (IHC). Results were stratified using clinical and follow-up data (2/32 patients had metastatic disease and 4/32 died of disease). We observed TB in 13/32 (40.6%) ITAC cases including the 7 patients with relapse (p = 0.0005) and the 4 patients dead of disease (p = 0.02). Lymphovascular invasion was associated with TB (p = 0.008). Absence of TB was associated with low ZEB2 expression (p = 0.003). No other association with EMT markers emerged. Occupational exposure to wood and leather dust was not related to the presence of TB. TB interobserver concordance was substantial (proportion of agreement = 87%; Cohen's kappa = 0.73). This work suggests that TB is associated with a worse prognosis in ITAC, but our findings do not seem to support the involvement of EMT in this specific setting. Further larger studies are needed to address this point.

Radiosensitization of Clioquinol Combined with Zinc in the Nasopharyngeal Cancer Stem-like Cells by Inhibiting Autophagy in Vitro and in Vivo

Loco-regional recurrence of nasopharyngeal carcinoma (NPC) after radiation therapy is one of the main types of treatment failure. This study is aimed to explore the possible causes of inside-field recurrence of NPC patients in order to develop effective treatment methods. Our study indicated that CD44 and autophagy proteins in tumor tissues of patients with recurrent NPC are higher than that of the relapse free patients. The in vitro experiments further confirmed that cancer stem cells (CSCs) were more radioresistant with enhanced autophagy activity. Treatment with clioquinol (CQ) combined with zinc could obviously enhance the radiosensitivity of CNE-2s cells through autophagy inhibition, activation of the caspase system and impairment of DNA damage repair. The in vivo experiments have further consolidated our findings. Our results suggest that CSCs and enhanced autophagy activity may be involved in the inside-field recurrence of NPC, and CQ combined with zinc could be an important therapeutic approach for recurrent NPC.

Hallmarks of cancer: Tumor budding as a sign of invasion and metastasis in head and neck cancer

Invasion and metastasis are hallmarks of cancer. The concept of tumor budding at tumor-host interface has been documented in many carcinomas. A growing body of evidence indicates that tumor budding is a sign of invasion and early step for metastasis of many epithelial cancers including head and neck squamous cell carcinoma (HNSCC). In addition, recent research has underlined the importance of tumor budding as a promising prognosticator in HNSCC. This review summarizes the findings regarding tumor budding in HNSCC and focuses on the role of tumor budding in invasion and metastasis. Also, we highlight the prognostic significance of tumor budding in HNSCC and its potential for improving clinical decision making in terms of recommending optimal individualized treatment for this patient population.

Immunolocalization of Cancer Stem Cells Marker ALDH1 and its Association with Tumor Budding in Oral Squamous Cell Carcinoma

Tumor budding is a prognostic marker for oral squamous cell carcinoma (OSCC) characterized by the presence of isolated or small clusters of neoplastic cells at the tumor invasive front. Aldehyde dehydrogenase-1 (ALDH1) is associated with tumorigenesis, linked to treatment resistance and shown to identify cancer stem cells (CSC)-like cells. This study aimed to evaluate the expression of ALDH1 and its association with tumor budding in OSCC. Immunohistochemistry was employed in 163 OSCC samples to identify pancytokeratin (AE1/AE3) and ALDH1. While pancytokeratin (AE1/AE3) identified squamous tumor buds, the CSC-like cells were identified using ALDH1. A Chi square test was used to evaluate association between ALDH1 expression and tumor budding, while McNemar's test was used to identify differences in ALDH1 expression between the budding area and the area outside the budding. A positive expression of ALDH1 was observed in 47.24% of the samples and in 70% of anatomic locations affected. No association was observed between ALDH1 expression and tumor budding (p > 0.05). In tumors with high-intensity tumor budding, ALDH1 expression was higher in the budding area than in the area outside the budding (p < 0.05). The finding that tumor bud cells in OSCC show phenotypic characteristics of CSC-like cells reinforces the relevance of tumor budding in determining the biological behavior of this malignant neoplasm. Moreover, the presence of CSC-like cells in nearly half of evaluated samples of OSCC and in most of the affected anatomic locations is in accordance with the CSC model of oral carcinogenesis.

Expression of CD44, CD44v9, ABCG2, CD24, Bmi-1 and ALDH1 in stage I and II oral squamous cell carcinoma and their association with clinicopathological factors

Cancer stem cells (CSCs) exhibit self-replication, self-differentiation, drug resistance and immune evasion activities. In recent years CSCs have become increasingly important for the treatment of malignant tumors. CSCs express specific markers, including cluster of differentiation (CD)44, CD44 variant 9 (CD44v9), ATP-binding cassette sub-family G member 2 (ABCG2), CD24, B lymphoma Mo-MLV insertion region 1 homolog (BMI-1) and aldehyde dehydrogenase 1 (ALDH1). However, the prognostic value of their expression in patients with oral squamous cell carcinoma (OSCC) are not well known. The present study evaluated these markers in stage I and II patients with OSCC and examined the association between T classification, histological differentiation, classification of invasion mode, lymph node metastasis and disease-free survival rate. Tissue specimens were obtained from 70 patients with stage I or II OSCC following either surgery or biopsy. Immunohistochemistry was performed and positive staining was defiend as 10% positive cells. CD44 and CD44v9 expressions were strongly detected in all OSCC tissues compared with normal epithelial cells. A total of 22 (31.4%) cases expressed ABCG2 and there was a significant association between ABCG2 expression and invasion. A total of 41 cases (59.0%) expressed CD24 and there was a significant association between CD24 expression and invasion. A total of 33 cases (47.1%) expressed BMI-1 and there was a significant association between BMI-1 expression and the disease-free survival rate. A total of 18 cases (25.7%) expressed ALDH1. Although there was no association between ALDH1 expression and T classification, there were significant associations between ALDH1 expression and histological differentiation, invasion mode, metastasis and the disease-free survival rate. Multivariate analysis revealed that ALDH1 expression was the only prognostic factor for disease-free survival rate. The results of the present study suggest that the positivity of ALDH1 detected in patients with OSCC correlates with the number of cells undergoing epithelial mesenchymal transition and metastasis. These findings indicated that the expression of ALDH1 may be an effective prognostic marker indicating the survival of patients with stage I and II OSCC.

Decreased miR-320a promotes invasion and metastasis of tumor budding cells in tongue squamous cell carcinoma. Oncotarget. 2016;7:65744-65757. [PMID: 27582550 PMCID: PMC5323189 DOI: 10.18632/oncotarget.11612]

We aimed to determine the specific miRNA profile of tumor budding cells and investigate the potential role of miR-320a in invasion and metastasis of tongue squamous cell carcinoma (TSCC). We collected tumor budding cells and paired central tumor samples from five TSCC specimens with laser capture microdissection and examined the specimens using a miRNA microarray. The specific miRNA signature of tumor budding cells was identified. We found that miR-320a was dramatically decreased in tumor budding cells. Knockdown of miR-320a significantly enhanced migration and invasion of TSCC cell lines. Suz12 was shown to be a direct target of miR-320a. Similar results were also observed in nude mouse models. Multivariate analysis indicated that miR-320a was an independent prognostic factor. Kaplan–Meier analysis demonstrated that decreased miR-320a and high intensity of tumor budding were correlated with poor survival rate, especially in the subgroup with high-intensity tumor budding and low expression of miR-320a. We concluded that decreased expression of miR-320a could promote invasion and metastasis of tumor budding cells by targeting Suz12 in TSCC. A combination of tumor budding and miR-320a may serve as an index to identify an aggressive sub-population of TSCC cells with high metastatic potential.

Predictive Significance of Tumor Depth and Budding for Late Lymph Node Metastases in Patients with Clinical N0 Early Oral Tongue Carcinoma

In clinical N0 early oral tongue carcinoma, treatment of occult lymph node metastasis is controversial. The purpose of this study was to assess the histopathological risk factors for predicting late lymph node metastasis in early oral tongue carcinoma. We retrospectively reviewed 48 patients with early oral tongue squamous cell carcinoma. Associations between the histopathological factors (depth of tumor, differentiation, blood vessel invasion, lymphatic invasion, and tumor budding) and late lymph metastasis were analyzed. Although the univariate analysis identified blood vessel invasion, lymphatic invasion, and high-grade tumor budding as predictive factors for neck recurrence (p < 0.001), the Cox proportional hazards model identified high-grade tumor budding as an independent predictive factor (p < 0.01). The combination of a tumor depth ≥ 3 mm and high-grade tumor budding yielded high diagnostic accuracy. Tumor depth and budding grade were identified as histopathological risk factors for late neck recurrence in clinical N0 early oral tongue carcinoma.

Cell proliferation is associated with intensity of tumor budding in oral squamous cell carcinoma

BACKGROUND

Tumor budding is a morphological marker of cancer invasion, defined as the presence of isolated or small clusters of neoplastic cells at the tumor invasive front. This study aimed to evaluate the association between intensity of tumor budding and cell proliferation in oral squamous cell carcinoma (OSCC).

METHODS

Immunohistochemistry was employed in 163 OSCC samples to detect the cell proliferation marker Ki-67 and multicytokeratin (to identify OSCC cells in tumor budding evaluation). The Mann-Whitney test was used to evaluate differences in the cell proliferation index between samples with high-intensity tumor budding and samples with low-intensity or no tumor budding. In samples with high-intensity tumor budding, the Wilcoxon test was used to evaluate differences in the cell proliferation index between the budding area and the area outside the budding. The chi-square test assessed the association between cell proliferation index and intensity of tumor budding.

RESULTS

The cell proliferation index was higher in samples with high-intensity tumor budding than in samples with low-intensity or no tumor budding (P < .05). Tumors with high-intensity tumor budding showed a higher cell proliferation index in the budding area than in the area outside the budding (P < .05). Finally, samples showing high-intensity tumor budding were associated with high cell proliferation index (P < .05).

CONCLUSION

Cell proliferation is positively associated with intensity of tumor budding in OSCC. Moreover, in tumors showing high-intensity tumor budding, the budding area is the location of higher cell proliferation. These findings reinforce the hypothesis that tumor budding is associated with the biological behavior of OSCC.

High ALDH1 expression correlates with better prognosis in tumorigenic malignant melanoma

Aldehyde dehydrogenase 1 (ALDH1) has been proposed as biomarker of stem cells for certain human cancers. ALDH1 expression has been correlated with poor patient outcomes in a variety of malignancies but better patient outcomes in others, and its prognostic significance in malignant melanoma is unclear. Thus, 68 melanoma patients with comprehensive clinical and pathologic follow-up data were used to construct a tissue microarray. A modified histological score (H-score) with a maximum score of 300 was used to quantify immunohistochemical staining for ALDH1. Survival time was defined as the time between diagnosis and melanoma-specific death. Using univariate logistic regression, a low (<80 H-score) ALDH1 score showed 3.7-fold increase in risk for melanoma-specific death within 10 years when compared with high (>80) ALDH1 levels (P=0.017). Odds of MSD were lower by a factor of ~0.9 for each 10-point increase in H-Score. Median survival time was 44.1 months and 180.9 months for patients with low and high ALDH1 expression, respectively. Using multivariate analysis, ALDH1 H-score was found to be an independent prognostic factor. These findings suggest that ALDH1 expression in malignant melanoma has a favorable effect on patient survival. Further study is needed elucidate the function of this enzymatic protein in melanoma progression.

Reproducibility, repeatability, and level of difficulty of two methods for tumor budding evaluation in oral squamous cell carcinoma

BACKGROUND

This study aimed to analyze the reproducibility, repeatability, and level of difficulty of two methods for tumor budding evaluation in oral squamous cell carcinoma (OSCC): staining by hematoxylin and eosin (HE) and immunostaining for multicytokeratin.

METHODS

The evaluation of tumor budding was performed by three examiners in 103 samples of OSCC, using the two methods. A Likert-type scale was used to measure the difficulty in the assessment. The interexaminer agreement (reproducibility) was estimated using Fleiss's kappa and the intra-examiner agreement (repeatability) was estimated using Cohen's kappa. The agreement between the two methods was evaluated using Cohen's Kappa. The Friedman test was used to compare the three examiners' perceived levels of difficulty of assessment. The Wilcoxon test was used to compare the level of difficulty of the evaluation between the two methods.

RESULTS

Reproducibility by the immunostaining method for multicytokeratin was substantial, being higher than the only fair agreement by the HE. Repeatability by the HE ranged from moderate to substantial among examiners, regardless of the examiner's experience. Repeatability by the immunostaining method for multicytokeratin did not vary among examiners, showing almost perfect agreement. The agreement between the two methods ranged from fair to moderate among examiners, being lower in the less experienced examiner. All the examiners presented greater difficulty in the evaluation by the HE.

CONCLUSION

In view of the unsatisfactory agreement between the two methods of tumor budding evaluation in OSCC, it is recommended that this evaluation should be performed by the immunostaining method for multicytokeratin, considering its higher reproducibility, greater replicability, and lower difficulty compared to the HE.

ALDH1 and podoplanin expression patterns predict the risk of malignant transformation in oral leukoplakia

Oral leukoplakia (OL) is a clinically diagnosed preneoplastic lesion of the oral cavity with an increased oral cancer risk. However, the risk of malignant transformation is still difficult to assess. The objective of the present study was to examine the expression patterns of aldehyde dehydrogenase 1 (ALDH1) and podoplanin in OL, and to determine their roles in predicting oral cancer development. In the present study, the expression patterns of ALDH1 and podoplanin were determined in samples from 79 patients with OL. The association between protein expression and clinicopathological parameters, including oral cancer-free survival, was analyzed during a mean follow-up period of 3.4 years. Expression of ALDH1 and podoplanin was observed in 61 and 67% patients, respectively. Kaplan-Meier analysis demonstrated that the expression of the proteins was correlated with the risk of progression to oral cancer. Multivariate analysis revealed that expression of ALDH1 and podoplanin was associated with 3.02- and 2.62-fold increased risk of malignant transformation, respectively. The malignant transformation risk of OL was considerably higher in cases with expression of both proteins. Point-prevalence analysis revealed that 66% of patients with co-expression of ALDH1 and podoplanin developed oral cancer. Taken together, our data indicate that ALDH1 and podoplanin expression patterns in OL are associated with oral cancer development, suggesting that ALDH1 and podoplanin may be useful biomarkers to identify OL patients with a substantially high oral cancer risk.

Inflammation-Related DNA Damage and Cancer Stem Cell Markers in Nasopharyngeal Carcinoma

Nitrative and oxidative DNA damage plays an important role in inflammation-related carcinogenesis. To investigate the involvement of stem cells in Epstein-Barr virus infection-related nasopharyngeal carcinoma (NPC), we used double immunofluorescence staining to examine several cancer stem/progenitor cell markers (CD44v6, CD24, and ALDH1A1) in NPC tissues and NPC cell lines. We also measured 8-nitroguanine formation as an indicator of inflammation-related DNA lesions. The staining intensity of 8-nitroguanine was significantly higher in cancer cells and inflammatory cells in the stroma of NPC tissues than in chronic nasopharyngitis tissues. Expression levels of CD44v6 and ALDH1A1 were significantly increased in cancer cells of primary NPC specimens in comparison to chronic nasopharyngitis tissues. Similarly, more intense staining of CD44v6 and ALDH1A1 was detected in an NPC cell line than in an immortalized nasopharyngeal epithelial cell line. In the case of CD24 staining, there was no significant difference between NPC and chronic nasopharyngitis tissues. 8-Nitroguanine was detected in both CD44v6- and ALDH1A1-positive stem cells in NPC tissues. In conclusion, CD44v6 and ALDH1A1 are candidate stem cell markers for NPC, and the increased formation of DNA lesions by inflammation may result in the mutation of stem cells, leading to tumor development in NPC.

Identification of genes involved in Epstein-Barr virus-associated nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is the most common cancer originating from the nasopharynx, and can be induced by infection with Epstein-Barr virus (EBV). To study the mechanisms of EBV-associated NPC, a microarray of the GSE12452 dataset was analyzed. GSE12452 was downloaded from Gene Expression Omnibus and consisted of 31 NPC samples and 10 normal healthy nasopharyngeal tissue samples. The differentially-expressed genes (DEGs) were screened using the linear models for microarray data package in R. Using Database for Annotation, Visualization and Integrated Discovery software, potential functions of the DEGs were predicted by Gene Ontology and pathway enrichment analyses. With the information from the Search Tool for the Retrieval of Interacting Genes/Proteins database, the protein-protein interaction (PPI) network was visualized by Cytoscape. Furthermore, modules of the PPI network were searched using ClusterONE in Cytoscape. A total of 951 DEGs were screened in the NPC samples compared with the normal healthy nasopharyngeal tissue samples. Function enrichment indicated that the upregulated genes were associated with the cell cycle, cytoskeleton organization and DNA metabolism. Meanwhile, the downregulated genes were mainly associated with cell differentiation, hormone metabolism, inflammatory response and immune response. PPI networks for the DEGs suggested that upregulated mitotic arrest deficient 2-like 1 (MAD2L1; degree=133), proliferating cell nuclear antigen (PCNA; degree=125) and cyclin B1 (CCNB1; degree=115), and downregulated member A1 of aldehyde dehydrogenase 1 (ALDH1A1; degree=15) may be of great importance as they exhibited higher degrees on interaction. Mucin 1 (MUC1) was a key node of module 4. Overall, the study indicated that MAD2L1, CCNB1, PCNA, ALDH1A1 and MUC1 may have a correlation with EBV-associated NPC.

Tumor Budding: The Name is EMT. Partial EMT

Tumor budding is a histological phenomenon encountered in various cancers, whereby individual malignant cells and/or small clusters of malignant cells are seen in the tumor stroma. Postulated to be mirror epithelial-mesenchymal transition, tumor budding has been associated with poor cancer outcomes. However, the vast heterogeneity in its exact definition, methodology of assessment, and patient stratification need to be resolved before it can be routinely used as a standardized prognostic feature. Here, we discuss the heterogeneity in defining and assessing tumor budding, its clinical significance across multiple cancer types, and its prospective implementation in clinical practice. Next, we review the emerging evidence about partial, rather than complete, epithelial-mesenchymal phenotype at the tumor bud level, and its connection with tumor proliferation, quiescence, and stemness. Finally, based on recent literature, indicating a co-expression of epithelial and mesenchymal markers in many tumor buds, we posit tumor budding to be a manifestation of this hybrid epithelial/mesenchymal phenotype displaying collective cell migration.

Impact of peritumoral and intratumoral budding in esophageal adenocarcinomas

Tumor budding has prognostic significance in many carcinomas and is defined as the presence of detached isolated single cells or small cell clusters up to 5 cells at the invasion front (peritumoral budding [PTB]) or within the tumor (intratumoral budding [ITB]). For esophageal adenocarcinomas (EACs), there are currently only few data about the impact of this morphological feature. We investigated tumor budding in a large collective of 200 primarily resected EACs. Pancytokeratin staining was demonstrated to be superior to hematoxylin and eosin staining for the detection of buds with substantial to excellent interobserver agreement and used for subsequent analysis. PTB and ITB were scored across 10 high-power fields (HPFs). The median count of tumor buds was 130/10 HPFs for PTB (range, 2-593) and 80/10 HPFs for ITB (range, 1-656). PTB and ITB correlated significantly with each other (r = 0.9; P < .001). High PTB and ITB rates were seen in more advanced tumor categories (P < .001 each); tumors with lymph node metastases (P < .001/P = .002); and lymphatic, vascular, and perineural invasion and higher tumor grading (P < .001 each). Survival analysis showed an association with worse survival for high-grade ITB (P = .029) but not PTB (P = .385). However, in multivariate analysis, lymph node and resection status, but not ITB, were independent prognostic parameters. In conclusion, PTB and ITB can be observed in EAC to various degrees. High-grade budding is associated with aggressive tumor phenotype. Assessment of tumor budding, especially ITB, may provide additional prognostic information about tumor behavior and may be useful in specific cases for risk stratification of EAC patients.

Tumor budding and laminin5-γ2 in squamous cell carcinoma of the external auditory canal are associated with shorter survival

Squamous cell carcinoma (SCC) of the external auditory canal (EAC) is rare, usually presents at an advanced stage, and is a more aggressive tumor with poor prognosis. The University of Pittsburgh TNM staging system commonly used in prognostication is not perfect, and more accurate biomarkers predicting prognosis are needed. Tumor budding is an established negative prognostic factor at the invasive front in colorectal cancer. Moreover, immunohistochemical studies showed that laminin 5-γ2 (Ln5-γ2) is expressed at the invasive front in tumor or tumor budding cells. We assessed the prognostic significance of tumor budding and Ln5-γ2 expression by performing Ln5-γ2 immunohistochemistry and evaluated the degree of tumor budding in pre-treatment biopsy specimens, and investigated their correlations to clinicopathological parameters in patients with SCC of the EAC. Patients whose tumors had high budding grade and Ln5-γ2 expression had significantly shorter survival times. Budding grade was significantly correlated with Ln5-γ2 expression. Multivariate analysis revealed that high budding grade predicted poorer prognosis regardless of disease stage. Our results suggested that budding grade and Ln5-γ2 expression can be used as indicators of poor prognosis in patients with SCC of the EAC.

Histologic assessment of tumor budding in preoperative biopsies to predict nodal metastasis in squamous cell carcinoma of the tongue and floor of the mouth

BACKGROUND

In squamous cell carcinoma (SCC) of the tongue and the floor of the mouth (FOM), it is important to predict lymph node metastasis, including occult metastasis, before operating. The purpose of this study was for us to determine practical histopathologic parameters as predictive factors for lymph node metastasis in preoperative SCC biopsy specimens.

METHODS

We examined 91 cases of SCC for conventional histopathologic assessment and a new factor, tumor budding, and their relationship with lymph node metastasis.

RESULTS

Significant factors via univariate analysis (p < .01) were budding (score ≥3) and tumor depth (≥3 mm) and these were associated with lymph node metastasis. Moreover, both budding and tumor depth significantly correlated with relapse-free survival; however, evaluating biopsy specimens often proved inaccurate for predicting true tumor depth of cancer invasion.

CONCLUSION

Tumor budding using immunohistochemistry for cytokeratin should be added to routine histologic assessments as a new criterion factoring into the decision as to whether neck dissection is indicated. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1582-E1590, 2016.

The expression of aldehyde dehydrogenase 1 (ALDH1) in ovarian carcinomas and its clinicopathological associations: a retrospective study

Background

Aldehyde dehydrogenase 1 (ALDH1) is widely used as a specific cancer stem cell marker in a variety of cancers, and may become a promising target for cancer therapy. However, the role of its expression in tumor cells and the microenvironment in different cancers is still controversial.

Methods

To clarify the clinicopathological effect of ALDH1 expression in ovarian carcinoma, a series of 248 cases of paraffin-embedded formalin fixed ovarian carcinoma tissues with long term follow-up information were studied by immunohistochemistry.

Results

The immunostaining of ALDH1was variably detected in both tumor cells and the stromal cells, although the staining in tumor cells was not as strong as that in stromal cells. Statistical analyses showed that high ALDH1 expression in tumor cells was significantly associated with histological subtypes, early FIGO stage, well differentiation grade and better survival probability (p < 0.05). The expression of ALDH1 in the stromal cells had no clinicopathological associations in the present study (p > 0.05).

Conclusioms

High expression of cancer stem cell marker ALDH1 in ovarian carcinoma cells may thus portend a favorable prognosis, but its expression in tumor microenvironment may have no role in tumor behavior of ovarian carcinomas. More studies are warranted to find out the mechanisms for this.

Five miRNAs as novel diagnostic biomarker candidates for primary nasopharyngeal carcinoma

MicroRNAs (miRNAs) play an essential role in the development and progression of nasopharyngeal carcinomas (NPC). Despite advances in the field of cancer molecular biology and biomarker discovery, the development of clinically validated biomarkers for primary NPC has remained elusive. In this study, we investigated the expression and clinical significance of miRNAs as novel primary NPC diagnostic biomarkers. We used an array containing 2, 500 miRNAs to identify 22 significant miRNAs, and these candidate miRNAs were validated using 67 fresh NPC and 25 normal control tissues via quantitative real-time PCR (qRT-PCR). Expression and correlation analyses were performed with various statistical approaches, in addition to logistic regression and receiver operating characteristic curve analyses to evaluate diagnostic efficacy. qRT-PCR revealed five differentially expressed miRNAs (miR-93-5p, miR-135b-5p, miR-205-5p and miR-183-5p) in NPC tissue samples relative to control samples (p<0.05), with miR-135b-5p and miR-205-5p being of significant diagnostic value (p<0.01). Moreover, comparison of NPC patient clinicopathologic data revealed a negative correlation between miR-93-5p and miR- 183-5p expression levels and lymph node status (p<0.05). These findings display an altered expression of many miRNAs in NPC tissues, thus providing information pertinent to pathophysiological and diagnostic research. Ultimately, miR-135b-5p and miR-205-5p may be implicated as novel NPC candidate biomarkers, while miR- 93-5p, miR-650 and miR-183-5p may find application as relevant clinical pathology and diagnostic candidate biomarkers.

Cancer stem-like cell: a novel target for nasopharyngeal carcinoma therapy

Nasopharyngeal carcinoma (NPC) is the most common cancer originating in the nasopharynx, and is extremely common in southern regions of China. Although the standard combination of radiotherapy and chemotherapy has improved the efficiency in patients with NPC, relapse and early metastasis are still the common causes of mortality. Cancer stem-like cells (CSCs) or tumor initial cells are hypothesized to be involved in cancer metastasis and recurrence. Over the past decade, increasing numbers of studies have been carried out to identify CSCs from human NPC cells and tissues. The present paper will summarize the investigations on nasopharyngeal CSCs, including isolation, characteristics, and therapeutic approaches. Although there are still numerous challenges to translate basic research into clinical applications, understanding the molecular details of CSCs is essential for developing effective strategies to prevent the recurrence and metastasis of NPC.

CD38 is a putative functional marker for side population cells in human nasopharyngeal carcinoma cell lines

Cancer stem cells (CSCs) are thought to be responsible for cancer progression and therapeutic resistance but identification of this subpopulation requires selective markers. Fortunately, side population (SP) cells analysis brings a novel method to CSCs study. In this study, we identified SP cells, which are demonstrated rich in CSCs, in four nasopharyngeal carcinoma (NPC) cell lines. We investigated SP cells from HK-1 NPC cell line and showed CSCs characteristics in this subpopulation. SP cells displayed greater proliferation and invasion and expressed high levels of CSCs markers than NSP cells. Furthermore, our microRNA microarray analysis of SP versus NSP cells revealed that CD38-related miRNAs were down-regulated in SP cell, but the mRNA and protein level of CD38 were highly expressed in SP cells. We further searched for molecules interacting with CD38 and identified ZAP70, which was also well expressed in SP cells at both mRNA and protein levels. Our results uncover a CD38 pathway that may regulate the proliferation and migration of SP cells from HK-1 NPC cell line.

Histopathological features predict metastatic potential in locally advanced colon carcinomas

Background

Metastatic dissemination can exist before a pathologically and clinically detectable manifestation. The structural heterogeneity of colon cancer (CC) in histological sections with respect to the morphology of tumor aggressiveness and composition of the tumor microenvironment raises the question of whether the microscopical tumor architecture enables a discrimination of groups with different metastatic potential. This would result in an assessment of the prognosis and provision of an ancillary tool for the therapeutic management after surgery, beside the estimation of the local tumor extent.

Methods

In order to identify predictive biomarkers for metastasis of locally advanced CC, which can easily be integrated into the pathologist’s daily routine diagnostic activity, we determined tumor budding, peritumoral inflammation, extent of desmoplasia and necrosis, density of macro- and microvascular blood vessels and functional state of lymphatics in the tumor center, invasive margin and tumor-free surrounding tissue in 86 non-metastatic, lymphogenous-metastatic and haematogenous-metastatic, subserosa-invasive CC.

Results

Features influencing nodal metastasis in the univariate analysis included high tumor budding (p = 0.004), high large vessel density in the subserosa (p = 0.043), abundant desmoplasia (p = 0.049), non-finger-like desmoplastic pattern (p = 0.051) and absent lymphocellular intratumoral inflammation (p = 0.084). In the multivariate analysis, with the exception of large vessel density, these pathomorphological features were independent risk factors for lymphogenous metastasis (p = 0.023, p = 0.017, p = 0.037, p = 0.012, respectively) with a good discrimination ability (AUC of 0.853). Features associated with distant metastasis in the univariate analysis included high tumor budding (p = 0.002), low intratumoral small vessel density (p = 0.013), absent lymphocellular intratumoral inflammation (p = 0.048) and abundant necrosis (p = 0.073). In the multivariate analysis only tumor budding was an independent predictor for haematogenous metastasis (p = 0.007) with a good discrimination ability (AUC of 0.829).

Conclusions

Thus, mainly tumor budding but also the described structural characteristics of the peritumoral tissue appears to reflect the metastatic potential of locally advanced CC and therefore should be stated in pathological reports.

Tyrosine kinase receptor B (TrkB) expression in colorectal cancers highlights anoikis resistance as a survival mechanism of tumour budding cells

AIMS

Tumour buds in colorectal cancer represent an aggressive subgroup of non-proliferating and non-apoptotic tumour cells. We hypothesize that the survival of tumour buds is dependent upon anoikis resistance. The role of tyrosine kinase receptor B (TrkB), a promoter of epithelial-mesenchymal transition and anoikis resistance, in facilitating budding was investigated.

METHODS AND RESULTS

Tyrosine kinase receptor B immunohistochemistry was performed on a multiple-punch tissue microarray of 211 colorectal cancer resections. Membranous/cytoplasmic and nuclear expression was evaluated in tumour and buds. Tumour budding was assessed on corresponding whole tissue slides. Relationship to Ki-67 and caspase-3 was investigated. Analysis of Kirsten Ras (KRAS), proto-oncogene B-RAF (BRAF) and cytosine-phosphate-guanosine island methylator phenotype (CIMP) was performed. Membranous/cytoplasmic and nuclear TrkB were strongly, inversely correlated (P < 0.0001; r = -0.41). Membranous/cytoplasmic TrkB was overexpressed in buds compared to the main tumour body (P < 0.0001), associated with larger tumours (P = 0.0236), high-grade budding (P = 0.0011) and KRAS mutation (P = 0.0008). Nuclear TrkB was absent in buds (P <0.0001) and in high-grade budding cancers (P =0.0073). Among patients with membranous/cytoplasmic TrkB-positive buds, high tumour membranous/cytoplasmic TrkB expression was a significant, independent adverse prognostic factor [P = 0.033; 1.79, 95% confidence interval (CI) 1.05-3.05]. Inverse correlations between membranous/cytoplasmic TrkB and Ki-67 (r = -0.41; P < 0.0001) and caspase-3 (r =-0.19; P < 0.05) were observed.

CONCLUSIONS

Membranous/cytoplasmic TrkB may promote an epithelial-mesenchymal transition (EMT)-like phenotype with high-grade budding and maintain viability of buds themselves.

Tumour budding in head and neck squamous cell carcinoma - a systematic review

Tumour budding is a specific type of invasive growth in carcinomas characterized by invading single tumour cells or small clusters of tumour cells (<5 cells) at the invasive front (IF). It has been documented in numerous publications during the past few decades, but its value as a prognostic marker in head and neck squamous cell carcinoma (HNSCC) has been analysed only recently. In this review we aimed to address the question of whether or not tumour budding has an impact upon the progression and prognosis of HNSCC. We systematically reviewed the databases of PubMed, Scopus and Web of Science for articles that studied tumour budding in squamous cell carcinoma of the head and neck region. The search was limited to articles published in the English literature before March 2014. A total of 122 hits were retrieved; however, only five reports met the inclusion criteria. The findings of these reports suggested a strong association between tumour budding and tumour progression, in addition to strong correlation with patient prognosis. Standardization of the scoring method and the risk stratification cut-off point is necessary before the inclusion of tumour budding in pathological reports during daily practice.

Cancer stem-like cells in Epstein-Barr virus-associated nasopharyngeal carcinoma

Although the Epstein-Barr virus (EBV) has spread to all populations in the world, EBV-associated nasopharyngeal carcinoma (NPC) is prevalent only in South China and Southeast Asia. The role of EBV in the malignant transformation of nasopharyngeal epithelium is the main focus of current researches. Radiotherapy and chemoradiotherapy have been successful in treating early stage NPC, but the recurrence rates remain high. Unfortunately, local relapse and metastasis are commonly unresponsive to conventional treatments. These recurrent and metastatic lesions are believed to arise from residual or surviving cells that have the properties of cancer stem cells. These cancer stem-like cells (CSCs) have the ability to self-renew, differentiate, and sustain propagation. They are also chemo-resistant and can form spheres in anchorage-independent environments. This review summarizes recent researches on the CSCs in EBV-associated NPC, including the findings regarding cell surface markers, stem cell-related transcription factors, and various signaling pathways. In particular, the review focuses on the roles of EBV latent genes [latent membrane protein 1 (LMP1) and latent membrane protein 2A (LMP2A)], cellular microRNAs, and adenosine triphosphate (ATP)-binding cassette chemodrug transporters in contributing to the properties of CSCs, including the epithelial-mesenchymal transition, stem-like transition, and chemo-resistance. Novel therapeutics that enhance the efficacy of radiotherapy and chemoradiotherapy and inhibitors that suppress the properties of CSCs are also discussed.

Tumor budding correlates with occult cervical lymph node metastasis and poor prognosis in clinical early-stage tongue squamous cell carcinoma

BACKGROUND

Tumor budding has been suggested to be a prognostic factor in various human cancers. However, the prognostic value of tumor budding for early-stage (cT1/2N0) tongue squamous cell carcinoma remains inconclusive. This study analyzed the correlation of tumor budding with the clinicopathologic features, and its prognostic significance for cT1/2N0 stage tongue squamous cell carcinoma.

METHODS

One hundred and ninety-five patients with T1/2 stage tongue squamous cell carcinoma enrolled in the retrospective study. Tumor invasive depth, the intensity of tumor budding, and other clinicopathological features were reviewed. Overall survivals were evaluated by the Kaplan-Meier method. For multivariable analysis, Cox's proportional hazards regression models were performed.

RESULTS

The frequency of tumor buds in tongue squamous cell carcinoma is about 85.6% in this study. The intensity of tumor budding showed strong correlations with occult lymph node metastasis (P < 0.05), local relapse (P < 0.01), worse invasive pattern (P < 0.01), and invasive depth (P < 0.05). The invasive depth was significantly associated with T classification (P < 0.01) and lymph node metastasis (P < 0.01). And both high intensity of tumor budding and deeper invasive depth correlated with reduced overall survival. Cox's regression models proved tumor budding to be an independent prognostic factor in clinical early-stage tongue squamous cell carcinoma. Tumor local relapses were also a predictor of tongue squamous cell carcinoma progression.

CONCLUSIONS

Tumor budding is a frequent event in tongue squamous cell carcinoma. It independently predicted prognosis of patients with T1/2 stage tongue squamous cell carcinoma and may be used for routing pathological diagnosis and the decision of elective lymph node dissection.