Annexin A2 (AnxA2) association with the clinicopathological data in different breast cancer subtypes: A possible role for AnxA2 in tumor heterogeneity and cancer progression

BACKGROUND

Breast cancer is a highly heterogeneous type of neoplasia with molecular and biochemical alterations in the ductal epithelium. AnxA2 has a diverse functions and through intracellular interaction with other molecules promotes carcinogenesis.

AIMS

To study the possible involvement of AnxA2 in breast cancer heterogeneity and cancer progression.

PATIENTS AND METHODS

Tumor tissue and serum were obtained from different breast cancer subtypes. Tumor tissues were processed for histopathological studies. AnxA2 levels were assessed in the tissues by H scoring and in the serum by ELISA. AnxA2 levels were correlated with HER2 and Ki67 and with clinicopathological data. Normal breast tissues and serum from healthy subjects were used as controls.

RESULTS

AnxA2 showed a peculiar distribution in tumor tissues and nearby interstitial tissues. Pattern of expressions varied in different subtypes with the highest expression in triple negative subtype. Tissue and serum AnxA2 showed significant co-upregulations in breast cancer. Moreover, they showed positive correlations with HER2 and Ki67 and associations with clinicopathological data including cancer staging and lymph node metastasis.

CONCLUSION

For the best of our knowledge this is the first study showing correlation between AnxA2, the proposed prognostic marker and the well-established tumor markers; HER2 and Ki67. AnxA2 might contribute to breast cancer heterogeneity and is associated with poor prognosis. AnxA2 might be a prognostic marker and an additional marker for breast cancer grading and clinical staging. Interestingly, tissue and serum AnxA2 showed a strong correlation. Thus, assessing serum AnxA2 can be a noninvasive prognostic tool.

Differences in clinicopatholgic characteristics and risk of mortality between the triple positive and ER+/PR+/HER2- breast cancer subtypes

PURPOSE

This study compared the demographic and clinicopathologic characteristics and risk of mortality between the triple positive (TP) and ER+/PR+/HER2- breast cancer subtypes.

METHODS

Cases of first primary female invasive TP and ER+/PR+/HER2- breast cancer were obtained from the California Cancer Registry. Logistic regression analysis was used to compare differences in factors associated with the TP versus the ER+/PR+/HER2- subtype. Cox regression was used to compute the adjusted risk of breast cancer-specific mortality of the TP versus ER+/PR+/HER2-.

RESULTS

The odds of TP versus ER+/PR+/HER2- were higher with advanced stage, high grade, low SES, ≤ 45 years of age (OR 1.48; CI 1.40-1.55), black (OR 1.11; CI 1.02-1.21), Asian/Pacific Islander (OR 1.15; CI 1.09-1.22), and uninsured (OR 1.42; CI 1.15-1.73). Unadjusted survival analysis indicated worse survival for the TP when compared with the ER+/PR+/HER2- subtype. However, adjusted risk of mortality for the TP subtype was not statistically significantly worse than the ER+/PR+/HER2- subtype.

CONCLUSIONS

Young age, advanced stage and grade, low SES, black and API race, and lack of health insurance are more common in the TP subtype than in the ER+/PR+/HER2- subtype. However the risk of mortality between these two subtypes is similar.

Triple positive breast cancer: a distinct subtype?

Breast cancer is a heterogeneous disease, and within the HER-2 positive subtype this is highly exemplified by the presence of substantial phenotypical and clinical heterogeneity, mostly related to hormonal receptor (HR) expression. It is well known how HER-2 positivity is commonly associated with a more aggressive tumor phenotype and decreased overall survival and, moreover, with a reduced benefit from endocrine treatment. Preclinical studies corroborate the role played by functional crosstalks between HER-2 and estrogen receptor (ER) signaling in endocrine resistance and, more recently, the activation of ER signaling is emerging as a possible mechanism of resistance to HER-2 blocking agents. Indeed, HER-2 positive breast cancer heterogeneity has been suggested to underlie the variability of response not only to endocrine treatments, but also to HER-2 blocking agents. Among HER-2 positive tumors, HR status probably defines two distinct subtypes, with dissimilar clinical behavior and different sensitivity to anticancer agents. The triple positive subtype, namely, ER/PgR/Her-2 positive tumors, could be considered the subset which most closely resembles the HER-2 negative/HR positive tumors, with substantial differences in biology and clinical outcome. We argue on whether in this subgroup the "standard" treatment may be considered, in selected cases, i.e., small tumors, low tumor burden, high expression of both hormonal receptors, an overtreatment. This article review the existing literature on biologic and clinical data concerning the HER-2/ER/PgR positive tumors, in an attempt to better define the HER-2 subtypes and to optimize the use of HER-2 targeted agents, chemotherapy and endocrine treatments in the various subsets.