No relationship between proliferative activity and the MACIS prognostic scoring system in papillary thyroid carcinoma

Relationship of body mass index with BRAF (V600E) mutation in papillary thyroid cancer

Current evidences suggest an influence of overweight body mass index (BMI) on the carcinogenesis in malignancies. However, the role of BMI is unclear in papillary thyroid cancer (PTC). The aim of the present study is to investigate the relationship between BMI and BRAF (V600E) mutation status in PTC. BRAF (V600E) mutation in 108 patients with PTC was analyzed by Sanger sequencing. The cutoff point of BMI was identified by X-tile for predicting mutation by overweight. Odds ratios (OR) and 95 % confidence interval (CI) of BRAF (V600E) mutation according to BMI and clinicopathologic variables were calculated using logistic regression models. Fifty-one patients were positive for BRAF (V600E) mutation. A positive relationship existed between BRAF (V600E) mutation and BMI (p = 0.039). A 24.3 kg/m(2) was identified as cutoff point for differentiating greater than 52.0 % observed probability of mutation for BRAF (V600E) in entire cohort, which was similar to the midpoint between the upper limit of normal BMI and overweight defined by WHO (≥24 kg/m(2)). Multivariate analysis confirmed the association between BRAF (V600E) mutation with overweight BMI range (OR 7.645, 95 % CI 1.275-45.831, p = 0.026). This study suggests an influence of overweight BMI on the status of BRAF (V600E) in patients with PTC, whereas the underlying mechanism need to be further investigated.

Comparison with published systems of a new staging system for papillary and follicular thyroid carcinoma

BACKGROUND

Several staging systems exist to estimate the prognosis for patients with thyroid carcinoma. Our goal was to develop a new staging system to predict cancer-specific survival (CSS) and evaluate it against published systems.

METHODS

The Cedars-Sinai Medical Center (CSMC)'s staging system was derived using data from an adjusted analysis of 1622 patients with differentiated thyroid carcinomas (DTCs) from the CSMC Thyroid Cancer Center. Mean follow-up time was 11.8 years. There were 1180 female and 442 male patients with a mean age of 46. Staging systems reviewed include University of Alabama (Birmingham) and M.D. Anderson Cancer Center (UAB-MDACC); the Tumor-Node-Metastasis (TNM) 5th and 7th editions; Memorial Sloan-Kettering (MSK); the National Thyroid Cancer Treatment Cooperative Study (NTCTCS); Ohio State; Clinical Class; Metastases, Age, Completeness of resection, Invasion, and tumor Size (MACIS); Noguchi; and the Yildirim model for predicting outcomes. The proportion of variance explained (PVE) and the C-index were computed to rank and compare each staging system's ability to predict CSS with this patient population.

RESULTS

Adjusted hazard ratios revealed that age at surgery of >45 years, the presence of distant metastases, capsular invasion, and vascular invasion were the most significant predictors of CSS in this patient population. The final CSMC risk score consists of low-, moderate-, and high-risk groups. Among the well-differentiated thyroid carcinoma staging systems, the CSMC and NTCTCS ranked highest with PVE values of 5% and 4.3%, respectively, while the NTCTCS and CSMC staging systems were reversed using the C-index (0.77 and 0.76, respectively).

CONCLUSION

The PVE and C-index values were relatively low across all applicable staging systems and varied in each study reviewed. This suggests that no one staging system has been shown to be superior to another across different patient populations with DTC. In the future, additional factors, such as biological markers, added to the clinical and pathological characteristics may lead to the development of superior staging systems.

Proliferative activity in oral salivary gland tumors: the role of PCNA and AgNOR assessed by a double staining technique

The aim of this study was to evaluate the role of PCNA and AgNOR in the assessment of salivary gland tumor proliferation using a double staining technique. Ten cases of pleomorphic adenoma (PA) and seventeen cases of adenoid cystic carcinoma (ACC) were examined. Numeric and morphometric parameters of AgNOR were evaluated and compared in PCNA-positive and PCNA-negative nuclei. There were statistically significant differences in AgNOR numbers, perimeters and contour indices between PCNA-positive and -negative nuclei in the PA samples. The ACC samples demonstrated significant differences only in the AgNOR areas. Our results show that in salivary gland tumors there is not always a relationship between proliferative activity evaluated by AgNOR numeric and morphometric parameters and PCNA immunostaining.

Molecular mechanism about lymphogenous metastasis of hepatocarcinoma cells in mice

AIM: To investigate the correlation between lymphogenous metastasis and matrix metalloproteinases (MMPs) activity and the expression of Fas ligand of tumor cells in lymph nodes.

METHODS: Fifty-six inbred 615-mice were equally divided into 2 groups and inoculated with Hca-F and Hca-P cells. Their lymph node metastatic rates were examined. Growth fraction of lymphocytes in host lymph nodes was detected by flow cytometry. The Hca-F and Hca-P cells were cultured with extract of lymph node, liver or spleen. The quantity of MMPs in these supernatants was examined by zymographic analysis. The expression of Fas ligand, PCNA, Bcl-2 protein of Hca-F and Hca-P cells in the mice were examined by immunohistochemistry. The apoptosis signals of macrophages in lymph nodes were observed with in situ DNA fragmentation.

RESULTS: On the 28^th day post-inoculation, the lymph node metastatic rate of Hca-F was 80% (16/20), whereas that of Hca-P was 25% (5/20). The growth fraction of lymphocytes was as follows: in the Hca-F cells, the proliferating peak of lymphocytes appeared on the 14^th day post-inoculation and then decreased rapidly, while in Hca-P cells, the peak appeared on the 7^th day post inoculation and then kept at a high level. With the extract of lymph node, the quantity of the MMP-9 activity increased (P < 0.01) and active MMP-9 and MMP-2 were produced by both Hca-F and Hca-P tumor cells, which did not produce MMPs without the extract of lymph node or with the extracts of the liver and spleen. The expression of Fas Ligand of Hca-F cells was stronger than that of Hca-P cells (P < 0.01). The expressions of PCNA and Bcl-2 protein of Hca-F cells in the tumors of inoculated area were the same as that of Hca-P cells. In situ DNA fragmentation showed that the positive signals of macrophages were around Hca-F cells.

CONCLUSION: Secretion of MMPs which was associated with metastatic ability of Hca-F and Hca-P tumor cells depends on the environment of lymph nodes. The increased expression of Fas ligand protein of Hca-F tumor cells with high lymphogenous metastatic potential in lymph nodes may help tumor cells escape from being killed by host lymphocytes.