Optimizing chemotherapy regimens for patients with early-stage breast cancer

Personalized chemotherapy selection for breast cancer using gene expression profiles

Choosing the optimal chemotherapy regimen is still an unmet medical need for breast cancer patients. In this study, we reanalyzed data from seven independent data sets with totally 1079 breast cancer patients. The patients were treated with three different types of commonly used neoadjuvant chemotherapies: anthracycline alone, anthracycline plus paclitaxel, and anthracycline plus docetaxel. We developed random forest models with variable selection using both genetic and clinical variables to predict the response of a patient using pCR (pathological complete response) as the measure of response. The models were then used to reassign an optimal regimen to each patient to maximize the chance of pCR. An independent validation was performed where each independent study was left out during model building and later used for validation. The expected pCR rates of our method are significantly higher than the rates of the best treatments for all the seven independent studies. A validation study on 21 breast cancer cell lines showed that our prediction agrees with their drug-sensitivity profiles. In conclusion, the new strategy, called PRES (Personalized REgimen Selection), may significantly increase response rates for breast cancer patients, especially those with HER2 and ER negative tumors, who will receive one of the widely-accepted chemotherapy regimens.

HAGE (DDX43) is a biomarker for poor prognosis and a predictor of chemotherapy response in breast cancer

Background:

HAGE protein is a known immunogenic cancer-specific antigen.

Methods:

The biological, prognostic and predictive values of HAGE expression was studied using immunohistochemistry in three cohorts of patients with BC (n=2147): early primary (EP-BC; n=1676); primary oestrogen receptor-negative (PER-BC; n=275) treated with adjuvant anthracycline-combination therapies (Adjuvant-ACT); and primary locally advanced disease (PLA-BC) who received neo-adjuvant anthracycline-combination therapies (Neo-adjuvant-ACT; n=196). The relationship between HAGE expression and the tumour-infiltrating lymphocytes (TILs) in matched prechemotherapy and postchemotherapy samples were investigated.

Results:

Eight percent of patients with EP-BC exhibited high HAGE expression (HAGE+) and was associated with aggressive clinico-pathological features (Ps<0.01). Furthermore, HAGE+expression was associated with poor prognosis in both univariate and multivariate analysis (Ps<0.001). Patients with HAGE+did not benefit from hormonal therapy in high-risk ER-positive disease. HAGE+and TILs were found to be independent predictors for pathological complete response to neoadjuvant-ACT; P<0.001. A statistically significant loss of HAGE expression following neoadjuvant-ACT was found (P=0.000001), and progression-free survival was worse in those patients who had HAGE+residual disease (P=0.0003).

Conclusions:

This is the first report to show HAGE to be a potential prognostic marker and a predictor of response to ACT in patients with BC.

Development and characterization of a colon PDX model that reproduces drug responsiveness and the mutation profiles of its original tumor

Cultures of primary tumors are very useful as a personalized screening system for effective therapeutic options. We here describe an effective method of reproducing human primary colon tumors through primary culture and a mouse xenograft model. A total of 199 primary colon tumor cultures were successfully established under optimized conditions to enrich for tumor cells and to expand it for long-term storage in liquid nitrogen. To examine whether these stored cultures retained original tumor properties, fifty primary cultures were xenografted into NOD-SCID mouse. Histological and tumor marker analysis of four representative tumor xenografts revealed that all of the xenograft retained its primary tumor characteristics. Oncomap analysis further showed no change in the major mutations in the xenografts, confirming that our method faithfully reproduced human colon tumors. A drug sensitivity assay revealed that two of the primary cultures were hypersensitive to oxaliplatin rather than 5-FU, which was used in the patients, suggesting it as an effective therapeutic option. We thus present an effective, reproducible preclinical model for testing various personalized therapeutic options in colon cancer patients.

Cancer therapy trials employing level-of-evidence-1 disease forecast cancer biomarkers uPA and its inhibitor PAI-1

Clinical research on cancer biomarkers is essential in understanding recent discoveries in cancer biology and heterogeneity of the cancer disease. However, there are only a few examples of clinically useful studies that have identified cancer biomarkers with clinical benefit. Urokinase-type plasminogen activator (uPA) and its inhibitor plasminogen activator inhibitor type 1 (PAI-1) are two of the few tumor tissue-associated cancer biomarkers that have been evaluated successfully and extensively in many preclinical and clinical studies for their clinical utility. Most of the studies have been conducted in early breast cancer to demonstrate the prognostic and predictive value for this malignancy. As a result of these investigations, uPA and PAI-1 have reached the highest level of clinical evidence, level of evidence 1. This article sheds light on the current status of major clinical Phase II and III breast cancer therapy trials (Chemo-N0, NNBC-3 and Plan B), and introduces ongoing clinical trials targeting uPA in advanced cancers of the breast and pancreas, employing synthetic small-size drugs to counteract uPA activity (WX-UK1, Mesupron(®)). The therapeutic effect of a uPA-derived small-size synthetic peptide (Å6) is tested in advanced ovarian cancer patients.