Crosstalk between EGFR and p53 in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most frequent cancers worldwide, with a high mortality. Most patients present with late stage disease, when the treatment options are limited to systemic chemotherapy. The purpose of our study was to evaluate the significance of p53 and EGFR expression in HCC, and to determine whether these two markers correlate with conventional parameters of prognosis.

MATERIALS AND METHODS

Our study included a total of 45 patients, diagnosed histopathologically with HCC. Clinicopathological data including sex, age, tumor necrosis, tumor size, histologic grading, tumor stage, the presence of cirrhosis and chronic hepatitis, were recorded from the Institute database. Three independent microscopic fields were selected for each sample and all the tumor cells within each microscopic field were counted, and then the positive percent of p53 cells were calculated. Three staining patterns were recognized: diffuse, heterogenous and focal. The intensity of EGFR staining was scored on a scale of 0-3+: 0 no staining; 1+ when a weak membrane staining was observed; 2+ when membrane staining is more intense than in 1+, but less than 3+, and 3+ when intense dark brown staining delineated the membrane. To determine the relationship between EGFR expression and p53, we performed double staining in the same HCC specimens.

RESULTS

By immunohistochemical staining, p53 protein was detected in tumor cell nuclei in 20 HCCs (44%). We found a significant correlation between the intensity of p53 expression and the histological grade (p=0.008). EGFR expression was detected in 17 (38%) cases, linked to histological grade (p=0.039). Moreover, the intensity of p53 expression was significantly correlated with EGFR intensity (p=0.014).

CONCLUSIONS

Our results suggest that overexpression of p53 and EGFR plays an important role in hepatocarcinogenesis and contributes to more advanced disease. These markers are not only valuable predictors of prognosis in HCC, but they are also rational targets for new anti-tumor strategies.

Prox 1, VEGF-C and VEGFR3 expression during cervical neoplasia progression as evidence of an early lymphangiogenic switch

Prox1 is a key regulator of lymphatic endothelial cell commitment during embryonic development. No correlations between Prox1 and VEGF-C/VEGFR3 expression in cervical cancer has been done until now. The aim of the present study was to evaluate the peculiarities of Prox1, VEGF-C and VEGFR3 expression during uterine cervix neoplasia progression. Material and methods. One hundred and four specimens taken from women with macroscopically detectable lesions were classified by histopathology and analyzed by immunohistochemistry for Prox1, VEGFR3 and VEGF-C expression. Results. The presence of Prox1 nuclear expression was detected starting from CIN2 and CIN3 lesions to microinvasive carcinoma, in the nuclei of lymphatic and venous endothelial cells and scattered stromal cells. All Prox1 positive lymphatic vessels were positive for VEGFR3. A significant correlation was found between expression of VEGF-C in tumor cells and nuclear density of Prox1 positive lymphatic cells (p=0.044). Conclusion. The commitment of Prox1 positive cells through a lymphatic lineage is an early event for cervical neoplastic progression, being present starting with intraepithelial cervical lesions, and is strongly associated with VEGFR3 and VEGF-C expression. These findings suggest an early active lymphangiogenesis during cervical neoplasia progression and explain, in part, the early presence of lymph node metastasis in cervical cancer. By the detection of Prox1 expression in lymphatic and venous endothelial cells, and also in stromal cells, it has been suggested that there are at least three different mechanism of lymph vessel development during cervical neoplasia progression.

Interplay between mast cells and lymphatic vessels in different molecular types of breast cancer

The particularities of lymphangiogenesis in different molecular types of breast cancer are virtually unknown and the contribution of microenvironment to this process has been ever less investigated. In the present study, we evaluated the relationships between lymphatic microvessel density (LMVD), mast cell density (MCD) and the different molecular subtypes of breast cancer. Molecular classification of breast tumors by immunohistochemistry was followed by the detection of mast cells and lymphatic vessels on the same slide by immunohistochemical double-stain method, using the lymphatic endothelial cell marker D2-40 and the mast cell tryptase. Mast cells and lymphatic vessels were simultaneously counted in the tumoral and peritumoral areas and results were compared with the molecular type, grade, lymphovascular invasion and lymph node status. Significant positive correlations were found between peritumoral MCD and LMVD for the luminal type-A breast cancers (p=0.025) and also for basal-like carcinomas (p=0.029). Moreover, a significant positive correlation was found between peritumoral and intratumoral MCD for basal-like carcinomas (p=0.009) and for overall MCD and LMVD. Low or inverse correlations between MCD and LMVD were also observed in other molecular subtypes of breast cancer. Our results strongly support that mast cells in the tumor microenvironment are keyplayers, involved in the development of tumor lymphatic vessels for some molecular subtypes of breast cancer.

Lymphatic microvessel density, VEGF-C, and VEGFR-3 expression in different molecular types of breast cancer

BACKGROUND

Breast cancer is a heterogeneous disease and five major distinct molecular types have been characterized by gene analysis and immunohistochemistry. The molecular types of breast cancer have different behavior, a particular profile of response to therapy, reflected in the differential survival of patients. Previous findings showed a particular preference for lymph node and distant metastases of different molecular types, but the specific lymphangiogenic profile of these types is lacking.

PATIENTS AND METHODS

We investigated the differential expression vascular endothelial growth factor-C (VEGF-C), vascular endothelial growth factor receptor-3 (VEGFR-3) and D2-40 by immunohistochemistry, to evaluate lymphangiogenesis and the lymphatic microvessel density (LMVD), in patients with breast cancer, stratified according to the molecular classification.

RESULTS

There was a differential expression of VEGF-C/VEGFR-3 and D2-40 in different molecular types of breast cancer, with highest level of expression for these markers being found in HER2 and luminal B types and the lowest in basal-like type. The lowest value of both intratumoral and peritumoral LMVD were found in normal-like type breast cancer. VEGF-C expression did not correlate with the grade of the tumor, but a significant correlation was found with lymph node metastasis. VEGFR-3 expression was found in 66.66% of the cases and correlated with the expression of VEGF-C in tumor cells. There was a positive correlation between VEGF-C, VEGFR-3 and LMVD only in the HER2 type, and a positive correlation in HER2 and normal-like types with VEGFR-3 expression in tumor cells. In addition, there was a correlation between HER2 type, VEGF-C and VEGFR-3 expression in tumor cells and lymphatic endothelium, respectively, and LMVD.

CONCLUSION

Our results support a differential signature of lymphangiogenesis in different molecular types of breast cancer and these findings may have a direct impact on prognosis and therapeutic strategy of this disease.

Characterization of endoglin and Ki-67 expression in endothelial cells from benign and malignant lesions of the uterine cervix

Activation of endothelial cells is often associated with the cellular proliferation in vitro. CD105 is a more specific marker of activated endothelial cells from tumor vessels and Ki-67 is used to assess the proliferation status of both tumor and endothelial cells. The aim of the present study was to evaluate the status of endothelial cells using CD105 and Ki-67 immunohistochemistry in benign and malignant lesions of the uterine cervix. Double stain for CD105/Ki-67 in benign and malignant lesions of the uterine cervix showed that these two markers had divergent expression on endothelial cells from associated tumor blood vessels dependent on lesion type and proliferation status of tumor cells. Absence of CD105/Ki-67 coexpression in endothelial cells was correlated with histopathology of the uterine cervix lesions and tumor proliferative status. The present findings suggest that CD105 expression is an early event, specific for premalignant lesions of the uterine cervix, while endothelial proliferation assessed on Ki-67 combined with the lack of CD105 expression is often associated with invasive cervical carcinoma.