Hormone receptor status rather than HER2 status is significantly associated with increased Ki-67 and p53 expression in triple-negative breast carcinomas, and high expression of Ki-67 but not p53 is significantly associated with axillary nodal metastasis in triple-negative and high-grade non-triple-negative breast carcinomas

Analysis of the radio-pathological factors of triple negative breast cancer and determination of risk profiles

OBJECTIVE

Triple-negative tumors are the most aggressive type of breast cancer. We aimed to analyze the main radiologic and histopathologic factors of these tumors to create a risk profile.

MATERIALS AND METHODS

We analyzed data from 140 patients diagnosed with triple-negative breast cancer between January 2007 and December 2016, with follow-up through April 2018. We analyzed the following variables in the breast MRI done for staging: size, necrosis, associated findings, adenopathies, and perfusion and diffusion parameters. We analyzed the following variables in histopathologic studies of biopsy specimens: histological type, Scarf-Bloom, Ki67, and p53 in the infiltrating component as well as in the in situ component. We analyzed the following variables in histopathologic studies of positive lymph nodes and surgical specimens: size, lymphovascular/perineural invasion, and microglandular adenosis. We analyzed the relation between the radiologic and histopathologic factors and recurrence and disease-free survival.

RESULTS

MRI tumor size>25mm, non-nodular enhancement, breast edema, areola-nipple complex retraction, and lymph-node involvement were associated with recurrence and lower disease-free survival. Invasive lobular carcinoma, postsurgical size>20mm, and p53<15% were also associated with recurrence and lower disease-free survival. Histologically positive lymph nodes were associated with a greater percentage of recurrence and lymphovascular invasion and with lower disease-free survival. The multivariate analysis found that the variables MRI size>25mm, non-nodular enhancement, adenopathies on MRI, and p53 expression <15% were independent predictors of lower disease-free survival.

CONCLUSIONS

In triple-negative breast tumors, factors associated with lower disease-free survival are non-nodular enhancement, size>25mm, and adenopathies on MRI, and p53 expression <15% on histopathologic study.

Does loss of hormonal receptors influence the pathophysiological characteristics of the HER-2 breast cancer phenotype?

BACKGROUND

Some breast carcinomas (BC) of the HER-2 type respond poorly to endocrine therapy, indicating that hormonal receptor (HR) status possibly impacts the biological criteria of this tumor class. The aim of this study was to compare the clinicopathological characteristics of HR-positive and HR-negative tumors occurring in HER-2 and non-HER-2 BC.

METHODS

Tissue microarray sections from 336 primary invasive BC specimens were stained immunohistochemically with antibodies against HER-2, ER, and PR. Proliferation was assessed using Ki67 and the P53 status was identified.

RESULTS

The HER-2 phenotype was identified in 42/336 (12.5%) specimens, while 293/336 (87.5%) were of the non-HER-2 phenotype. In the non-HER-2 group, 103/293 (35%) were HR-negative tumors. HR negativity was significantly associated with higher tumor grades (P < 0.0001), higher proliferation rates (P < 0.0001), presence of necrosis (P < 0.0001), and with a higher P53 expression (P < 0.0001). There were no differences in patient age, tumor size, LN status, or presence of vascular invasion (VI) between the HR-negative and HR-positive groups. In the HER-2 group, 16/42 (38%) had HR-negative tumors. No significant difference in clinicopathological characteristics, except for tumor grade, was detected between the HR-positive and HR-negative tumors in this group.

CONCLUSION

Loss of HR does not influence the biological features of HER-2 BC. This finding may indicate that some tumors will 'biologically' move from being HER-2-positive/HR-positive tumors to behaving more like HER-2-positive/HR-negative tumors even when ER are present on the cell surface. Further studies are needed to explore this hypothesis and to identify the subset of tumors that will benefit from endocrine therapy.

Expression and Clinical Significance of Claudin-7, PDL-1, PTEN, c-Kit, c-Met, c-Myc, ALK, CK5/6, CK17, p53, EGFR, Ki67, p63 in Triple-negative Breast Cancer-A Single Centre Prospective Observational Study

BACKGROUND/AIM

To explore the relationship between p53, p63, c-kit, Ki67, cMet, claudin7, CK5/6, CK17, AR, PTEN, EGFR, ALK, PDL-1 and c-MYC expression with the clinicopathological features of triple- negative breast cancer.

MATERIALS AND METHODS

Immunohistochemistry was performed in 84 triple-negative breast cancer samples.

RESULTS

A statistically significant relationship between tumour grade and claudin-7 (p=0.004) and between protein p53 and positive lymph nodes (p=0.015) was found. High expression of claudin-7 (OR=65.8, 95%CI=4.35-995.19, p-value=0.003) and low expression of c-kit (OR=0.14, 95%CI=0.025-0.793, p-value=0.026) and protein p63 (OR=0.18 95%CI=0.035-0.978, p-value=0.047) was associated with higher tumour grade. Higher AR expression (OR=13.44, 95%CI=1.28-141.56, p-value=0.031) and lower expression of CK5/6 cytokeratins was found in patients with positive lymphovascular invasion (LVI) (OR=0.072, 95%CI=0.007-0.732, p-value=0.026). Only the cell proliferation index (Ki67) has been proven to be statistically significant for disease-free survival (p-value=0.0378), and overall survival (p-value=0.0186).

CONCLUSION

High expression of claudin-7 and low expression of c-kit and protein p63 are associated with higher tumour grade. AR and CK5/6 expression seem to be important in LVI.

CREB3L1 as a potential biomarker predicting response of triple negative breast cancer to doxorubicin-based chemotherapy

Background

Doxorubicin-based chemotherapy is currently the most frequently used treatment for triple negative breast cancer (TNBC), yet the response rate is not high due to the lack of a biomarker allowing identification of responsive patients before the chemotherapy is initiated. We have demonstrated that doxorubicin inhibits proliferation of cancer cells through proteolytic activation of a transcription factor called CREB3L1 (cAMP response element binding protein 3-like 1), and that CREB3L1 expression in cancer cells is a key determinant of their sensitivity to doxorubicin when they are cultured in vitro or established as xenograft tumors in mice. The purpose of this study is to determine whether CREB3L1 expression in tumor cells of TNBC patients can be established as a biomarker to predict outcomes of doxorubicin-based chemotherapy.

Methods

We performed a retrospective analysis on breast core biopsy tissue samples taken from 18 TNBC patients before they were treated with doxorubicin-based chemotherapy. CREB3L1 expression in the cancer cells was analyzed by immunohistochemistry and quantified using the Immunoreactive Score (IRS). Outcomes of the chemotherapy were measured by the residual cancer burden (RCB) system.

Results

CREB3L1 expression levels in TNBC responsive to doxorubicin-based chemotherapy (RCB class 0-2) were significantly higher than that in resistant cancers (RCB class 3) (unpaired two-tailed t test, p = 0.0005; Statistical power 99.8 at 95% confidence level). All cancers expressing higher levels of CREB3L1 (IRS 4-12) responded to doxorubicin-based chemotherapy, whereas all cancers resisting the treatment expressed lower levels of CREB3L1 (IRS 0-3).

Conclusions

These results suggest that CREB3L1 expression level may be used as a biomarker to identify TNBC patients who are more likely to benefit from doxorubicin-based chemotherapy.

Neoadjuvant treatments in triple-negative breast cancer patients: where we are now and where we are going

Triple-negative breast cancer (TNBC) remains the poorest-prognosis breast cancer (BC) subtype. Gene expression profiling has identified at least six different triple-negative subtypes with different biology and sensitivity to therapies. The heterogeneous nature of TN tumors may justify the difficulty in treating this BC subtype. Several targeted agents have been investigated in clinical trials without demonstrating a clear survival benefit. Therefore, systemic chemotherapy remains the cornerstone of current clinical practice. Improving the knowledge of tumor biology is mandatory for patient management. In stages II and III, neoadjuvant systemic treatment is an effective option of care. The achievement of a pathological complete response represents an optimal surrogate for survival outcome as well as a test for tumor drug sensitivity. In this review, we provide a brief description of the main predictive biomarkers for tumor response to systemic treatment. Moreover, we review the treatment strategies investigated for TNBCs in neoadjuvant settings focusing on experimental drugs such as immunotherapy and poly [ADP-ribose] polymerase inhibitors that hold promise in the treatment of this aggressive disease. Therefore, the management of TNBC represents an urgent, current, unmet need in daily clinical practice. A key recommendation is to design biology-driven clinical trials wherein TNBC patients may be treated on the basis of tumor molecular profile.

Update on Immunohistochemical Analysis in Breast Lesions

CONTEXT

- The utility of immunohistochemistry (IHC) in breast lesions needs to be updated with exceptions among these lesions. Biomarker studies with IHC in triple-negative breast carcinoma may help develop targeted therapies for this aggressive breast cancer. The distinction of metastatic lung adenocarcinoma to the breast and invasive breast carcinoma has significant prognostic and therapeutic implications. The determination can be challenging because both primary tumors can express estrogen receptor and/or HER2 by IHC, creating a diagnostic dilemma.

OBJECTIVES

- To provide a practical update on the use of IHC markers in differential diagnoses in breast lesions, including benign, atypical, precancerous, and malignant tumors; to highlight recently published research findings on novel IHC markers in triple-negative breast carcinoma cases; and to reinforce the importance of IHC use as an ancillary tool in distinguishing metastatic lung adenocarcinoma to the breast from primary breast carcinoma using real case examples.

DATA SOURCES

- PubMed (US National Library of Medicine, Bethesda, Maryland) literature review and authors' research data and personal experiences were used in this review.

CONCLUSIONS

- Immunohistochemistry has an important role in making differential diagnoses in breast lesions in morphologically equivocal settings; recognizing IHC expression status in the exceptions among these lesions will aid in the correct diagnosis of challenging breast cases. Studies suggest that androgen receptor, p16, p53, GATA3, and PELP1 may have potential diagnostic, prognostic, and predictive value in triple-negative breast carcinoma cases; these findings may provide insight and a greater understanding of the tumor biology in triple-negative breast carcinomas. In distinguishing metastatic estrogen receptor-positive or HER2⁺ lung adenocarcinoma to the breast from primary breast carcinoma, napsin A, TTF-1, and GATA3 comprise a useful IHC panel.

Significantly increased PELP1 protein expression in primary and metastatic triple-negative breast carcinoma: comparison with GATA3 expression and PELP1's potential role in triple-negative breast carcinoma

PELP1 is a novel coregulator of nuclear hormone receptors and is implicated in playing a role in driving breast cancer and enhancing metastatic potential. The PELP1 protein expression and potential role of PELP1 in triple-negative breast carcinoma (TNBC) have not been well characterized. We investigated PELP1 expression by immunohistochemistry in primary and metastatic triple-negative tumors in human tissues and compared its expression with GATA-binding protein 3 (GATA3), a novel diagnostic marker for TNBC. We examined the expression of PELP1 and GATA3 in 70 primary TNBC cases and found that PELP1 had a significantly higher frequency of expression compared to GATA3 (96% versus 46%; P < .0001). The mean extent score of expression of PELP1 was also significantly higher than GATA3's expression (3.87 ± 0.07 versus 0.91 ± 0.15; P < .0001). PELP1 had stronger staining intensity than GATA3. Furthermore, PELP1 immunoreactivity was consistently maintained in paired primary and metastatic TNBC cases (100%). The frequency of PELP1 expression (100%) in metastatic triple-negative tumors was higher than that of GATA3 (40%) in the same tumors (P < .0001). These findings indicate that PELP1 is a much more sensitive marker than GATA3 for TNBCs. PELP1 may have diagnostic utility for metastatic TNBC in appropriate settings, such as history of primary TNBC in cases where the primary is negative for GATA3, mammaglobin, and GCDFP-15. The diffuse and strong nuclear immunoreactivity of PELP1 in most cases suggests that PELP1 may be a molecular target for the treatment of TNBC. We hope that this study will provide insights into the role of PELP1 in TNBC.

MTBP is overexpressed in triple-negative breast cancer and contributes to its growth and survival

Triple-negative breast cancer (TNBC) is a clinically aggressive subtype of breast cancer commonly resistant to therapeutics that have been successful in increasing survival in patients with estrogen receptor-positive (ER(+)) and HER2(+) breast cancer. As such, identifying factors that contribute to poor patient outcomes and mediate the growth and survival of TNBC cells remain important areas of investigation. MTBP (MDM2-binding protein), a gene linked to cellular proliferation and a transcriptional target of the MYC oncogene, is overexpressed in human malignancies, yet its contribution to cancer remains unresolved. Evaluation of mRNA expression and copy number variation data from The Cancer Genome Atlas (TCGA) revealed that MTBP is commonly overexpressed in breast cancer and 19% show amplification of MTBP. Increased transcript or gene amplification of MTBP significantly correlated with reduced breast cancer patient survival. Further analysis revealed that while MTBP mRNA is overexpressed in both ER(+) and HER2(+) breast cancers, its expression is highest in TNBC. MTBP mRNA and protein levels were also significantly elevated in a panel of human TNBC cell lines. Knockdown of MTBP in TNBC cells induced apoptosis and significantly reduced TNBC cell growth and soft agar colony formation, which was rescued by expression of shRNA-resistant Mtbp. Notably, inducible knockdown of MTBP expression significantly impaired TNBC tumor growth, in vivo, including in established tumors. Thus, these data emphasize that MTBP is important for the growth and survival of TNBC and warrants further investigation as a potential novel therapeutic target.

IMPLICATIONS

MTBP significantly contributes to breast cancer survival and is a potential novel therapeutic target in TNBC.

Prognostic effect of p53 expression in patients with completely resected colorectal cancer

The p53 protein is closely involved in the carcinogenesis of many kinds of cancers. Though the prognostic role of p53 expression for the survival of colorectal cancer (CRC) patients has been preliminarily identified, the prognostic effect of p53 expression in patients with completely resected CRC is still unclear. Therefore, a retrospective cohort study was performed to assess the prognostic role of p53 expression for overall survival in patients with completely resected CRC. A total of 153 patients (mean age 50.9 years) with completely resected CRC was finally included in the retrospective cohort study. Kaplan-Meier product-limit methods and log-rank test were used to estimate overall survival distribution and test the difference. In addition, multivariable analysis by Cox regression model was also used to test the prognostic role of p53 expression on overall survival by adjusting for other confounding factors. Of those 153 CRC patients, 62 (40.5 %) were positive for p53 protein expression in the tumor tissues. The log-rank test showed that there was an obvious difference in the overall survival between the p53-positive group and the p53-negative group (P < 0.001). Multivariable analysis by Cox regression model further showed that p53 protein expression was an independent predictor of shorter overall survival in patients with completely resected CRC (hazard ratio [HR] = 1.77; 95 % confidence interval [95 % CI] 1.15-2.71, P = 0.009). Therefore, p53 protein expression in the tumor tissue is an independent predictor of shorter overall survival in patients with completely resected CRC.

Overexpression of Raf-1 in basal-like carcinoma of the breast: correlation with clinicopathology and prognosis

Aim of the study

Increased Raf-1 expression has been associated with an aggressive behaviour in some carcinomas such as pulmonary carcinoma and renal carcinoma. However, its role in breast cancer, especially in basal-like carcinoma of the breast (BLBC), has not been defined.

Material and methods

The current study attempted to investigate the expression pattern of Raf-1 protein in BLBC, in relation to the biological behaviour and prognosis of the carcinoma. Expression of Raf-1 was detected by immunohistochemistry in carcinoma specimens from 74 cases of BLBC, and associations between their expression and the clinicopathological characteristics were statistically assessed.

Results

The patients’ age, tumour size, BRCA1, and p53 protein expression was not significantly different between the Raf-1-positive and Raf-1-negative expression groups (p > 0.05). The proportion of histological grade 3 tumours was not significantly higher in the Raf-1 positive group than that of grade 2 tumours (p > 0.05). However, positive cytoplasmic Raf-1 expression was positively correlated to Ki-67 expression (p < 0.05). Also, increased Raf-1 protein was found to exert an unfavourable impact on patients’ axillary lymph node metastasis and overall survival (p < 0.05).

Conclusions

The study implies that positive Raf-1 expression in BLBC is associated with a more aggressive phenotype and could be considered as a new prognostic biomarker for poor survival in BLBC patients.

Effect Modification of Hormonal Therapy by p53 Status in Invasive Breast Cancer

Purpose

We aimed to confirm the prognostic and predictive value of p53 expression, particularly in invasive breast cancer patients, according to immunohistochemical hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status.

Methods

Immunohistochemical data for p53, estrogen receptor, progesterone receptor, and HER2 expression from a total of 15,598 patients were retrospectively retrieved from the web-based database of the Korean Breast Cancer Society. Overall survival (OS) and breast cancer-specific survival (BCSS) were calculated and compared using the Kaplan-Meier method and log-rank test, respectively. Multivariate analyses were performed using a stratified Cox proportional hazard regression model. A model evaluating interactions between p53 expression and both hormonal therapy and chemotherapy was used to determine the treatment benefit from both modalities.

Results

The prognostic value of p53 for OS and BCSS was most significant in the HR+/HER2- subgroup, with hazard ratios of 1.44 (95% confidence interval [CI], 1.08-1.93) and 1.47 (95% CI, 1.09-1.99), respectively. The p53 overexpression hazard ratios were of borderline significance for the HR+/HER2+ subgroup and were not significant for the HR-/HER2+ and HR-/HER2- subgroups. The model with interaction terms revealed that hormonal therapy significantly interacts with p53 status (p=0.002 and p=0.007 for OS and BCSS, respectively), suggesting an insignificant prognostic value for p53 status (p=0.268 and p=0.296 for OS and BCSS, respectively). An interaction between chemotherapy and p53 status was not found in this model.

Conclusion

p53 overexpression has independent prognostic value, particularly in cases of HR+/HER2- invasive breast cancer, which may be due to effect modification of hormonal therapy dependent on p53 status.

A prognostic model for triple-negative breast cancer patients based on node status, cathepsin-D and Ki-67 index

Objective

The aim of this study was to evaluate clinicopathologic factors that could possibly affect the outcome of patients with triple negative breast cancer and subsequently build a prognostic model to predict patients’ outcome.

Methods

We retrospectively analyzed clinicopathologic characteristics and outcome of 504 patients diagnosed with triple-negative invasive ductal breast cancer. 185 patients enrolled between 2000 and 2002 were designated to the training set. The variables that had statistically significant correlation with prognosis were combined to build a model. The prognostic value of the model was further validated in the separate validation set containing 319 patients enrolled between 2003 and 2006.

Results

The median follow-up duration was 66 months. 174 patients experienced recurrence, and 111 patients died. Positivity for ≥4 lymph nodes, Cathepsin-D positivity, and Ki-67 index ≥20% were independent factors for DFS, while the lymph nodes status and Ki-67 index were the prognostic factors for OS. The prognostic model was established based on the sum of all three factors, where positivity for ≥4 lymph nodes, Cathepsin-D and Ki-67 index ≥20% would individually contribute 1 point to the risk score. The patients in the validation set were assigned to a low-risk group (0 and 1 point) and a high-risk group (2 and 3 points). The external validation analysis also demonstrated that our prognostic model provided the independent high predictive accuracy of recurrence.

Conclusion

This model has a considerable clinical value in predicting recurrence, and will help clinicians to design an appropriate level of adjuvant treatment and schedule adequate appointments of surveillance visits.

Roles of p53 and p16 in triple-negative breast cancer

SUMMARY p53 and p16 are both tumor suppressors. This article summarizes the current investigation status on their roles and interaction in triple-negative breast cancer (TNBC) to explore their potential as prognostic, predictive and therapeutic targets. There is significant evidence implicating that p53 mutation as a driver plays an important role in tumorigenesis and progression of TNBC. p53 mutations are more frequently observed in TNBCs compared with ER-positive breast cancers. The presence of a p53 mutation is associated with poorer prognosis in TNBC patients. The status of p53 protein expression divides TNBCs into two biologically distinct subgroups (p53-positive vs p53-negative); p53-positive tumors have more aggressive behavior. p53 has clinical prognostic utility and is a promising target candidate for directed therapy for TNBC patients. p16 appears to play a significant role in tumorigenesis of TNBC through the Rb/p16 dysfunction pathway. A high level of p16 protein expression is associated with aggressive behavior and tumor proliferation of TNBC. The status of p16 expression may have potential predictive value for TNBC response to chemotherapy; further investigation is needed to support the proposal. p16 expression has been strongly correlated with p53 expression in TNBC, suggesting interactions between the two mutations in tumorigenesis. It has been proposed that the two tumor suppressors appear to be involved in early events of TNBC formation with subsequent interplay resulting in their mutual inactivation and, ultimately, leading to a proliferative environment.

Hormone receptor and ERBB2 status in gene expression profiles of human breast tumor samples

The occurrence of large publically available repositories of human breast tumor gene expression profiles provides an important resource to discover new breast cancer biomarkers and therapeutic targets. For example, knowledge of the expression of the estrogen and progesterone hormone receptors (ER and PR), and that of the ERBB2 in breast tumor samples enables choice of therapies for the breast cancer patients that express these proteins. Identifying new biomarkers and therapeutic agents affecting the activity of signaling pathways regulated by the hormone receptors or ERBB2 might be accelerated by knowledge of their expression levels in large gene expression profiling data sets. Unfortunately, the status of these receptors is not invariably reported in public databases of breast tumor gene expression profiles. Attempts have been made to employ a single probe set to identify ER, PR and ERBB2 status, but the specificity or sensitivity of their prediction is low. We enquired whether estimation of ER, PR and ERBB2 status of profiled tumor samples could be improved by using multiple probe sets representing these three genes and others with related expression.We used 8 independent datasets of human breast tumor samples to define gene expression signatures comprising 24, 51 and 14 genes predictive of ER, PR and ERBB2 status respectively. These signatures, as demonstrated by sensitivity and specificity measures, reliably identified hormone receptor and ERBB2 expression in breast tumors that had been previously determined using protein and DNA based assays. Our findings demonstrate that gene signatures can be identified which reliably predict the expression status of the estrogen and progesterone hormone receptors and that of ERBB2 in publically available gene expression profiles of breast tumor samples. Using these signatures to query transcript profiles of breast tumor specimens may enable discovery of new biomarkers and therapeutic targets for particular subtypes of breast cancer.

Frequent low expression of chromatin remodeling gene ARID1A in breast cancer and its clinical significance

BACKGROUND

ARID1A gene encodes BAF250a which is a member of the ARID family of DNA-binding proteins and a subunit of human SWI/SNF-related complexes. Low expression of ARID1A has been correlated with specific tumor cell lines or specific pathological types of cancer tissue. The purpose of this study was to investigate the expression of ARID1A in invasive ductal breast carcinomas and to evaluate its clinicopathological characteristics and prognostic value.

METHODS

ARID1A mRNA expression was evaluated by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) in 40 pairs of fresh frozen breast cancer and normal breast samples. BAF250a expression was evaluated by immunohistochemistry in 112 paraffin-embedded surgical specimens of invasive breast cancers and 20 cases of matched normal breast tissues. We further analyzed the clinicopathological characteristics of ARID1A expression. Overall survival time was assessed by the Kaplan-Meier method and Cox regression model.

RESULTS

ARID1A mRNA expression was lower in breast cancer tissue than in corresponding normal tissue (P<0.001), and this decreased expression level was markedly associated with factors such as larger tumor size (P=0.038), higher stage (P=0.016), ER(-) (P=0.038), higher Ki-67 (P=0.025), P53 mutation (P=0.018) and ER(-)/PR(-)/Her-2(-) molecular subtype (P=0.044). With immunohistochemical staining, we showed that low BAF250a expression existed in 56% (63/112) of the breast cancers tissues. Low BAF250a expression was significantly associated with tumor stage (P=0.021), P53 (P=0.018), Ki-67 (P=0.031) and ER(-)/PR(-)/Her-2(-) molecular subtype (P=0.044). Low ARID1A expression was a predictor, not an independent, of overall survival.

CONCLUSION

These data suggest that low ARID1A expression is frequent in breast cancers, and we need to investigate further the role of ARID1A and SWI/SNF complexes in breast tumorigenesis, especially in triple-negative breast cancer.