The role of the CDH1 promoter hypermethylation in the axillary lymph node metastasis and prognosis

The Lymphatic System in Breast Cancer: Anatomical and Molecular Approaches

Breast cancer is one of the most important causes of premature mortality among women and it is one of the most frequently diagnosed tumours worldwide. For this reason, routine screening for prevention and early diagnosis is important for the quality of life of patients. Breast cancer cells can enter blood and lymphatic capillaries, then metastasizing to the regional lymph nodes in the axilla and to both visceral and non-visceral sites. Rather than at the primary site, they seem to enter the systemic circulation mainly through the sentinel lymph node and the biopsy of this indicator can influence the axillary dissection during the surgical approach to the pathology. Furthermore, secondary lymphoedema is another important issue for women following breast cancer surgical treatment or radiotherapy. Considering these fundamental aspects, the present article aims to describe new methodological approaches to assess the anatomy of the lymphatic network in the axillary region, as well as the molecular and physiological control of lymphatic vessel function, in order to understand how the lymphatic system contributes to breast cancer disease. Due to their clinical implications, the understanding of the molecular mechanisms governing lymph node metastasis in breast cancer are also examined. Beyond the investigation of breast lymphatic networks and lymphatic molecular mechanisms, the discovery of new effective anti-lymphangiogenic drugs for future clinical settings appears essential to support any future development in the treatment of breast cancer.

Studying Lymphatic Metastasis in Breast Cancer: Current Models, Strategies, and Clinical Perspectives

Breast cancer is the most commonly diagnosed cancer in women and the second most common cause of cancer-related deaths in the United States. Although early detection has significantly decreased breast cancer mortality, patients diagnosed with distant metastasis still have a very poor prognosis. The most common site that breast cancer spreads to are local lymph nodes. Therefore, the presence of lymph node metastasis remains one of most important prognostic factors in breast cancer patients. Given its significant clinical implications, increased efforts have been dedicated to better understand the molecular mechanism governing lymph node metastasis in breast cancer. The identification of lymphatic-specific biomarkers, including podoplanin and LYVE-1, has propelled the field of lymphatic metastasis forward. In addition, several animal models such as cell line-derived xenografts, patient-derived xenografts, and spontaneous tumor models have been developed to recreate the process of lymphatic metastasis. Moreover, the incorporation of various -omic platforms have provided further insight into the genetic drivers facilitating lymphatic metastasis, as well as potential biomarkers and therapeutic targets. Here, we highlight various models of lymphatic metastasis, their potential pitfalls, and other tools available to study lymphatic metastasis including imaging modalities and -omic studies.

Prognostic DNA methylation markers for hormone receptor breast cancer: a systematic review

BACKGROUND

In patients with hormone receptor-positive breast cancer, differentiating between patients with a low and a high risk of recurrence is an ongoing challenge. In current practice, prognostic clinical parameters are used for risk prediction. DNA methylation markers have been proven to be of additional prognostic value in several cancer types. Numerous prognostic DNA methylation markers for breast cancer have been published in the literature. However, to date, none of these markers are used in clinical practice.

METHODS

We conducted a systematic review of PubMed and EMBASE to assess the number and level of evidence of published DNA methylation markers for hormone receptor-positive breast cancer. To obtain an overview of the reporting quality of the included studies, all were scored according to the REMARK criteria that were established as reporting guidelines for prognostic biomarker studies.

RESULTS

A total of 74 studies were identified reporting on 87 different DNA methylation markers. Assessment of the REMARK criteria showed variation in reporting quality of the studies. Eighteen single markers and one marker panel were studied in multiple independent populations. Hypermethylation of the markers RASSF1, BRCA, PITX2, CDH1, RARB, PCDH10 and PGR, and the marker panel GSTP1, RASSF1 and RARB showed a statistically significant correlation with poor disease outcome that was confirmed in at least one other, independent study.

CONCLUSION

This systematic review provides an overview on published prognostic DNA methylation markers for hormone receptor-positive breast cancer and identifies eight markers that have been independently validated. Analysis of the reporting quality of included studies suggests that future research on this topic would benefit from standardised reporting guidelines.

Quantitation of CDH1 promoter methylation in formalin-fixed paraffin-embedded tissues of breast cancer patients using differential high resolution melting analysis

BACKGROUND

E-cadherin (CDH1) plays an important role in cell-cell adhesion of epithelial tissues. Loss of E-cadherin expression can lead to loss of tissue integrity, metastasis, and cancer progression. Also loss of E-cadherin expression might be related to aberrant promoter methylation of the CDH1 gene. Many studies have been performed on CDH1 promoter methylation, especially in breast cancer. Although most of the studies have used qualitative methods for methylation analysis, this study is designed to quantitatively investigate CDH1 promoter methylation in breast cancer and its correlation with patients' clinicopathological features.

MATERIALS AND METHODS

Using differential high resolution melting analysis (D-HRMA), the methylation level of the CDH1 gene promoter was quantified in 98 breast cancer formalin-fixed paraffin-embedded (FFPE) tissues and also 10 fresh frozen normal breast tissues.

RESULTS

All samples were detected to be methylated at the CDH1 promoter region. About 74.5% of the breast cancer samples were hypermethylated with an average methylation level of around 60%, while 25.5% of the patients were methylated with the mean methylation level of about 33%, and 90% of the normal samples had a mean methylation level of about 18%. Statistical analyses represented a significant correlation between CDH1 promoter methylation and cancer progression hallmarks, such as, clinical stage, nodal involvement, tumor size, and histological grade.

CONCLUSION

In summary, quantitation of CDH1 promoter methylation can serve as a diagnostic and prognostic tool in breast cancer. Also D-HRMA can be used as a fast and reliable method for quantitation of promoter methylation.

Prognostic significance of E-cadherin expression in hepatocellular carcinoma: a meta-analysis

Backgrounds

Hepatocellular Carcinoma (HCC) is one of the most common malignancy of liver and HCC-related morbidity and mortality remains at high level. Researchers had investigated whether and how reduced E-cadherin expression impacted the prognosis of patients with HCC but the results reported by different teams remain inconclusive.

Methods

A systematic literature search was performed in all available databases to retrieve eligible studies and identify all relevant data, which could be used to evaluate the correlation between reduced E-cadherin expression and clinicopathological features and prognosis for HCC patients. A fixed or random effects model was used in this meta-analysis to calculate the pooled odds ratios (OR) and weighted mean differences (WMD) with 95% confidence intervals (CI).

Results

Total 2439 patients in thirty studies matched the selection criteria. Aggregation of the data suggested that reduced E-cadherin expression in HCC patients correlated with poor 1-, 3- and 5-year overall survival. The combined ORs were 0.50 (n = 13 studies, 95% CI: 0.37–0.67, Z = 4.49, P<0.00001), 0.39 (n = 13 studies, 95% CI: 0.28–0.56, Z = 5.12, P<0.00001), 0.40 (n = 11 studies, 95% CI: 0.25–0.64, Z = 3.82, P = 0.0001), respectively. Additionally, the pooled analysis denoted that reduced E-cadherin expression negatively impacts recurrence-free survival (RSF) with no significant heterogeneity. The pooled ORs for 1-, 3- and 5- year RSF affected by down-regulated E-cadherin were 0.73 (n = 6 studies, 95% CI: 0.54–1.00, Z = 1.95, P = 0.05), 0.70 (n = 6 studies, 95% CI: 0.52–0.95, Z = 2.32, P = 0.02), 0.66 (n = 5 studies, 95% CI: 0.48–0.90, Z = 2.64, P = 0.008). And what’s more, reduced E-cadherin expression tended to be significantly associated with metastasis (OR = 0.31, 95% CI: 0.16–0.60, Z = 3.50, P = 0.0005), vascular invasion (OR = 0.76, 95% CI: 0.59–0.98, Z = 2.14, P = 0.03), advanced differentiation grade (OR = 0.31, 95% CI: 0.21–0.45, Z = 6.04, P<0.00001) and advanced TMN stage (T3/T4 versus T1/T2) (OR = 0.61,95% CI:0.38–0.98, Z = 2.05, P = 0.04).

Conclusions

Reduced E-cadherin expression indicates a poor prognosis for patients with HCC, and it may have predictive potential for prognosis of HCC patients.

Decreased expression of C10orf10 and its prognostic significance in human breast cancer

Breast cancer is a common malignant tumor, which severely threatens the health of women with an increasing incidence in many countries. Here, we identified C10orf10 as a novel differentially expression gene using expression microarray screening. The expression analysis indicated that C10orf10 was frequently decreased in human breast cancers compared to noncancerous breast tissues (81/95, P = 0.0063). Kaplan-Meier analysis indicated that patients with low C10orf10 expression showed a poorer prognosis both in mRNA (n = 1115, P = 0.0013) and protein (n = 100, P = 0.003) levels. Univariate and multivariate analysis showed that the C10orf10 expression was an independent prognostic factor for overall survival of breast cancer patients. Further analysis revealed that low expression of C10orf10 was an unfavorable factor for the prognosis of the patients who were luminal A, luminal B, Her2+ subtypes, at histological grade 2, lymph node negative and ER positive. Our data provided the first evidence that C10orf10 expression was frequently decreased in breast cancer tissues, and low expression of C10orf10 may be an important prognostic factor for poorer survival time of breast cancer patients.