The use of an in vitro adenosine triphosphate-based chemotherapy response assay to predict chemotherapeutic response in breast cancer

High-Throughput Chemotherapeutic Drug Screening System for Gastric Cancer (Cure-GA)

BACKGROUND

Three dimensional (3D) cell cultures can be effectively used for drug discovery and development but there are still challenges in their general application to high-throughput screening. In this study, we developed a novel high-throughput chemotherapeutic 3D drug screening system for gastric cancer, named 'Cure-GA', to discover clinically applicable anticancer drugs and predict therapeutic responses.

METHODS

Primary cancer cells were isolated from 143 fresh surgical specimens by enzymatic treatment. Cell-Matrigel mixtures were automatically printed onto the micropillar surface then stabilized in an optimal culture medium for 3 days to form tumoroids. These tumoroids were exposed in the drug-containing media for 7 days. Cell viability was measured by fluorescence imaging and adenosine triphosphate assays. On average, 0.31 ± 0.23 g of fresh tumor tissue yielded 4.05×106 ± 4.38×106 viable cells per sample.

RESULTS

Drug response results were successfully acquired from 103 gastric cancer tissues (success rate = 72%) within 13 ± 2 days, averaging 6.4 ± 2.7 results per sample. Pearson correlation analysis showed viable cell numbers significantly impacted drug data acquisition (p < 0.00001). Tumoroids retained immunohistochemical characteristics, mutation signatures, and gene expression consistent with primary tumors. Drug reactivity data enabled prediction of synergistic drug correlations. Additionally, a multiparameter index-based prognosis model for patients undergoing gastrectomy followed by adjuvant XELOX was developed, showing significant differences in 1-year recurrence-free survival rates between drug responders and non-responders (p < 0.0001).

CONCLUSIONS

The Cure-GA platform enables rapid evaluation of chemotherapeutic responses using patient-derived tumoroids, providing clinicians with crucial insights for personalized treatment strategies and improving therapeutic outcomes.

The Immune Response of Cancer Cells in Breast and Gynecologic Neoplasms

Cancer diseases constitute a major health problem which leads to the death of millions of people annually. They are unique among other diseases because cancer cells can perfectly adapt to the environment that they create themselves. This environment is usually highly hostile and for normal cells it would be hugely difficult to survive, however neoplastic cells not only can survive but also manage to proliferate. One of the reasons is that they can alter immunological pathways which allow them to be flexible and change their phenotype to the one needed in specific conditions. The aim of this paper is to describe some of these immunological pathways that play significant roles in gynecologic neoplasms as well as review recent research in this field. It is of high importance to possess extensive knowledge about these processes, as greater understanding leads to creating more specialized therapies which may prove highly effective in the future.

Benefits of functional assays in personalized cancer medicine: more than just a proof-of-concept

As complex and heterogeneous diseases, cancers require a more tailored therapeutic management than most pathologies. Recent advances in anticancer drug development, including the immuno-oncology revolution, have been too often plagued by unsatisfying patient response rates and survivals. In reaction to this, cancer care has fully transitioned to the “personalized medicine” concept. Numerous tools are now available tools to better adapt treatments to the profile of each patient. They encompass a large array of diagnostic assays, based on biomarkers relevant to targetable molecular pathways. As a subfamily of such so-called companion diagnostics, chemosensitivity and resistance assays represent an attractive, yet insufficiently understood, approach to individualize treatments. They rely on the assessment of a composite biomarker, the ex vivo functional response of cancer cells to drugs, to predict a patient's outcome. Systemic treatments, such as chemotherapies, as well as targeted treatments, whose efficacy cannot be fully predicted yet by other diagnostic tests, may be assessed through these means. The results can provide helpful information to assist clinicians in their decision-making process. We explore here the most advanced functional assays across oncology indications, with an emphasis on tests already displaying a convincing clinical demonstration. We then recapitulate the main technical obstacles faced by researchers and clinicians to produce more accurate, and thus more predictive, models and the recent advances that have been developed to circumvent them. Finally, we summarize the regulatory and quality frameworks surrounding functional assays to ensure their safe and performant clinical implementation. Functional assays are valuable in vitro diagnostic tools that already stand beyond the “proof-of-concept” stage. Clinical studies show they have a major role to play by themselves but also in conjunction with molecular diagnostics. They now need a final lift to fully integrate the common armament used against cancers, and thus make their way into the clinical routine.

Tumor Chemosensitivity Assays Are Helpful for Personalized Cytotoxic Treatments in Cancer Patients

Tumor chemosensitivity assays (TCAs), also known as drug response assays or individualized tumor response tests, have been gaining attention over the past few decades. Although there have been strong positive correlations between the results of these assays and clinical outcomes, they are still not considered routine tests in the care of cancer patients. The correlations between the assays' results (drug sensitivity or resistance) and the clinical evaluations (e.g., response to treatment, progression-free survival) are highly promising. However, there is still a need to design randomized controlled prospective studies to secure the place of these assays in routine use. One of the best ideas to increase the value of these assays could be the combination of the assay results with the omics technologies (e.g., pharmacogenetics that gives an idea of the possible side effects of the drugs). In the near future, the importance of personalized chemotherapy is expected to dictate the use of these omics technologies. The omics relies on the macromolecules (Deoxyribonucleic acid -DNA-, ribonucleic acid -RNA-) and proteins (meaning the structure) while TCAs operate on living cell populations (meaning the function). Therefore, wise combinations of TCAs and omics could be a highly promising novel landscape in the modern care of cancer patients.

Correlation of Early Recurrence With In Vitro Adenosine Triphosphate Based Chemotherapy Response Assay in Pancreas Cancer With Postoperative Gemcitabine Chemotherapy

INTRODUCTION

Gemcitabine-based regimens represent the standard systemic first line treatment in patients after pancreatic resection. However, the clinical impact of gemcitabine varies significantly in individuals because of chemoresistance. An in vitro adenosine triphosphate based chemotherapy response assay (ATP-CRA) was designed to evaluate the sensitivity of cancer cells to various chemotherapeutic agents. This study investigated the correlation between in vitro gemcitabine sensitivity of tumor cells and early recurrence after curative resection.

METHOD

From January 2007 to December 2010, the ATP-CRA for gemcitabine was tested in 64 patients surgically treated for pancreas cancer at Gangnam Severance Hospital, Seoul, Korea. We analyzed the relationship between chemosensitivity and early systemic recurrence in patients with pancreas cancer to predict disease-free survival (DFS) after curative resection in pancreas cancer.

RESULT

The mean cell death rate (CDR) was 20.0 (±14.5) and divided into two groups according to the mean values of the CDR. Lymphovascular invasion was more frequently shown in gemcitabine resistance group without statistical significance. In univariate and multivariate analysis, advanced tumor stage and gemcitabine sensitive group (CDR ≥ 20) were identified as independent prognostic factors for DFS.

CONCLUSIONS

Gemcitabine sensitivity measured by ATP-CRA was well correlated with in vivo drug responsibility to predict early recurrence following gemcitabine-based adjuvant chemotherapy in patients with pancreas cancer.

In Vitro Adenosine Triphosphate-Based Chemotherapy Response Assay as a Predictor of Clinical Response to Fluorouracil-Based Adjuvant Chemotherapy in Stage II Colorectal Cancer

PURPOSE

We evaluated the usefulness of the in vitro adenosine triphosphate-based chemotherapy response assay (ATP-CRA) for prediction of clinical response to fluorouracil-based adjuvant chemotherapy in stage II colorectal cancer.

MATERIALS AND METHODS

Tumor specimens of 86 patients with pathologically confirmed stage II colorectal adenocarcinoma were tested for chemosensitivity to fluorouracil. Chemosensitivity was determined by cell death rate (CDR) of drug-exposed cells, calculated by comparing the intracellular ATP level with that of untreated controls.

RESULTS

Among the 86 enrolled patients who underwent radical surgery followed by fluorouracil-based adjuvant chemotherapy, recurrence was found in 11 patients (12.7%). The CDR ≥ 20% group was associated with better disease-free survival than the CDR < 20% group (89.4% vs. 70.1%, p=0.027). Multivariate analysis showed that CDR < 20% and T4 stage were poor prognostic factors for disease-free survival after fluorouracil-based adjuvant chemotherapy.

CONCLUSION

In stage II colorectal cancer, the in vitro ATP-CRA may be useful in identifying patients likely to benefit from fluorouracil-based adjuvant chemotherapy.

Recent applications of chemosensitivity tests for colorectal cancer treatment

The evaluation of therapeutic efficacy is necessary to predict the outcome of patients with metastatic colorectal cancer (CRC). In these patients, there is a critical need for predictive chemosensitivity assays and biomarkers to optimize efficacy and minimize toxicity. The introduction of targeted agents has improved the progression-free survival and overall survival of patients with metastatic disease. However, approximately 50% of patients do not show a positive response to chemotherapy and the selection of patients likely to respond to a specific regimen remains challenging. Cell culture-based chemosensitivity tests use autologous viable tumor cells to evaluate susceptibility to specific agents in vitro and predict their direct effects. Adenosine triphosphate-based assays and methyl thiazolyl-diphenyl-tetrazolium bromide-based assays are used widely as sensitivity tests because of their short assay period, technical simplicity, and the requirement of small amount of specimen. Among protein- and gene-based chemosensitivity assays, assessment of KRAS mutation status predicts the response to epidermal growth factor receptor-targeted therapy in CRC patients. The validation of predictive and prognostic markers enables the selection of therapeutic regimens with optimal efficacy and minimal toxicity for each patient, which has been termed personalized treatment. This review summarizes currently available predictive and prognostic chemosensitivity tests for metastatic CRC.

ATP-based chemotherapy response assay in primary or recurrent ovarian and peritoneal cancer

PURPOSE

To investigate chemosensitivity with an adenosine triphosphate-based chemotherapy response assay in patients with epithelial ovarian or peritoneal cancer according to tumor histology, grade, and disease status.

MATERIALS AND METHODS

One hundred specimens were collected during primary or secondary debulking from 67 patients with primary ovarian cancer, 24 patients with recurrent ovarian cancer, 5 patients with primary peritoneal cancer, and 4 patients with recurrent peritoneal cancer; samples were collected between August 2006 and June 2009. Tumor cells were isolated and cultured for 48 hours in media containing chemotherapy. The chemosensitivity index (CI) was calculated as 300 minus the sum of the cell death rate at 0.2×, 1×, and 5× drug concentrations, and the CI values were compared.

RESULTS

CI values were obtained from 93 of 100 patients. The most active agents against primary disease were ifosfamide and paclitaxel. For primary serous adenocarcinoma, paclitaxel and irinotecan were the most active, followed by ifosfamide. For clear cell carcinoma, ifosfamide was the most active, followed by paclitaxel and irinotecan. Although not statistically significant, the CIs of cisplatin, carboplatin, paclitaxel, and docetaxel decreased as tumor grade increased. In 14 cases of recurrent disease, paclitaxel was the most active, followed by ifosfamide and cisplatin.

CONCLUSION

Ifosfamide and paclitaxel were the most active drugs for primary and recurrent disease. Therefore, we recommend further clinical studies to confirm the efficacy of paclitaxel, ifosfamide, and cisplatin combination chemotherapy for recurrent and primary ovarian cancer.

Purinergic signalling and cancer

Receptors for extracellular nucleotides are widely expressed by mammalian cells. They mediate a large array of responses ranging from growth stimulation to apoptosis, from chemotaxis to cell differentiation and from nociception to cytokine release, as well as neurotransmission. Pharma industry is involved in the development and clinical testing of drugs selectively targeting the different P1 nucleoside and P2 nucleotide receptor subtypes. As described in detail in the present review, P2 receptors are expressed by all tumours, in some cases to a very high level. Activation or inhibition of selected P2 receptor subtypes brings about cancer cell death or growth inhibition. The field has been largely neglected by current research in oncology, yet the evidence presented in this review, most of which is based on in vitro studies, although with a limited amount from in vivo experiments and human studies, warrants further efforts to explore the therapeutic potential of purinoceptor targeting in cancer.

AFP-producing acinar cell carcinoma treated by pancreaticoduodenectomy in a patient with a previous radical subtotal gastrectomy by gastric cancer

We report a case of alpha-fetoprotein (AFP)-producing acinar cell carcinoma (ACC) of the pancreas. The tumor was diagnosed in a 72 yearold female after radical subtotal gastrectomy (Billroth I) due to early gastric cancer six months before. The initial serum AFP levels were increased to 2,254.1 IU/ml and preoperative imaging studies showed a mass with approximately 2.5 cm in diameter near the neck of the pancreas. A pancreaticoduodenectomy was performed. The pathologic examination revealed an ill-defined lobulating tumor confined to the pancreas (T1 stage). Immunohistochemical study showed that the tumor cells expressed AFP. The Adenosine triphosphate-based chemotherapy response assay (ATP-CRA) suggested that cisplatin would be more desirable than gemcitabine in AFP-producing ACC of the pancreas as an adjuvant chemotherapy. However, the adjuvant chemotherapy was not performed due to the early pathological stage. The patient died from carcinomatosis and pneumonia. Even if the tumor was on a relatively early stage, an adjuvant treatment should be considered ACC.

Correlation between the molecular subtype of breast cancer and the in vitro adenosine triphosphate-based chemosensitivity assay

Purpose

The empirical use of a chemotherapy regimen shows different results in individual breast cancer patient treatment. Recent studies showed the effectiveness of the adenosine triphosphate-based chemotherapy response assay (ATP-CRA). However, little is known about the correlation between chemosensitivity and breast cancer molecular subtypes. Therefore, we investigated whether the result of ATP-CRA is associated with a molecular subtype of breast cancer.

Methods

Two hundred eighty-seven patients diagnosed with breast cancer and receiving ATP-CRA at Mokdong Hospital, Ewha Womans University between September 2007 and December 2010 were enrolled in this study. Hormone receptor status, HER2/neu expression, and results of chemosensitivity tests of the patients was analyzed.

Results

In all of four subtypes, the combination of two agents showed significant higher mean cell death rate than a single agent. Within the breast cancer cell lines in this study, the range of chemosensitivity response was very wide and varied for each patient. For this reason, the molecular subtype of breast cancer is inconclusive in choosing an effective chemotherapeutic agent and in vitro chemosensitivity test, prior to therapy, could be a useful method for planning chemotherapy for each patient.

Conclusion

Chemosensitivity response to anticancer agents was found to vary depending on the individual breast cancer patients. The molecular subtype of breast cancer is inconclusive to choose the effective chemotherapeutic agent and the in vitro chemosensitivity test, prior to therapy, could be more useful for planning chemotherapy for each patient.

Innovative in vitro chemo-hormonal drug therapy for refractory thyroid carcinomas

More than 95% of the thyroid carcinomas are well differentiated types showing favorable prognosis. However, only a few therapeutic options are available to treat the patients with undifferentiated thyroid carcinomas, especially with refractory thyroid carcinomas that are not amenable to surgery or radioiodine ablation. We investigated the anticancer effects of 20 chemotherapy and hormonal therapy drugs on 8 thyroid carcinoma cell lines. In vitro chemosensitivity was tested using the adenosine-triphosphate-based chemotherapy response assay (ATP-CRA). The tumor inhibition rate (TIR; or cell death rate) or half maximal inhibitory concentration (IC(50)) was analyzed to interpret the results. Of the 12 chemotherapy drugs, etoposide (178.9 index value in follicular carcinoma cell line) and vincristine (211.7 in Hürthle cell carcinoma cell line) were the most active drugs showing the highest chemosensitivity, and of the 8 additional drugs, trichostatin A (0.03 µg/mL IC(50) in follicular carcinoma cell line) showed favorable outcome having the anticancer effect. In our study, the result of etoposide and vincristine show evidence as active anticancer drugs in thyroid carcinoma cell lines and trichostatin A seems be the next promising drug. These drugs may become an innovative therapy for refractory thyroid carcinomas in near future.

Chemotherapy response assay test and prognosis for breast cancer patients who have undergone anthracycline- and taxane-based chemotherapy

PURPOSE

A chemotherapy response assay test is performed to evaluate the degree of tumor growth inhibition by a chemotherapeutic agent. Several studies have been done on its usefulness; however, to the best of our knowledge, only a few studies concerning the relationship between chemotherapy response assay test results and breast cancer patients' prognoses have been conducted. Thus, we performed this study to analyze this relationship.

METHODS

Among breast cancer patients who underwent curative surgery and neoadjuvant or adjuvant chemotherapy between August 2004 and December 2009, 102 were enrolled in this study. Chemotherapeutic regimens for patients were doxorubicin plus taxane or doxorubicin plus cyclophosphamide followed by taxane. We divided these patients into two groups (sensitive group [n=19] and resistant group [n=83]) and analyzed the relationship between chemosensitivity results and patient prognosis.

RESULTS

The sensitive group was associated with poor disease-free survival (DFS) (p=0.003) and overall survival (OS) (p<0.001). No significant differences were observed in tumor histology (p=0.548), tumor size (p=0.479), number of metastatic lymph nodes (p=0.326), histologic grade (p=0.077), or nuclear grade (p=0.216) between the two groups. However, in respect to molecular subtype, the HER2-positive type and triple negative breast cancer were more frequently observed in the sensitive group (p=0.001). In a univariate and multivariate analysis for DFS, doxorubicin sensitivity was significantly associated with a poor prognosis (p<0.05).

CONCLUSION

Better chemosensitivity results are associated with a poor prognosis in breast cancer patients who have undergone anthracycline- and taxane-based chemotherapy, however, examination of additional cases and the use of a longer study period are needed.

Adenosine triphosphate-based chemotherapy response assay-guided chemotherapy in unresectable colorectal liver metastasis

BACKGROUND

This study aims to evaluate the effectiveness of adenosine triphosphate-based chemotherapy response assay (ATP-CRA)-guided neoadjuvant chemotherapy for increasing resectability in patients with unresectable colorectal liver metastasis.

PATIENTS AND METHODS

Patients were randomised into two groups: Group A was treated by conventional chemotherapy regimen and Group B was treated by chemotherapy regimen according to the ATP-CRA. Three chemotherapeutic agents (5-fluorouracil, oxaliplatin and irinotecan) were tested by ATP-CRA and more sensitive agents were selected. Either FOLFOX or FOLFIRI was administered. Between Group A and B, treatment response and resectability were compared.

RESULTS

Between November 2008 and October 2010, a total 63 patients were randomised to Group A (N=32) or Group B (N=31). FOLFOX was more preferred in Group A than in Group B (26 out of 32 (81.3%) vs 20 out of 31 (64.5%)). Group B showed better treatment response than Group A (48.4% vs 21.9%, P=0.027). The resectability of hepatic lesion was higher in Group B (35.5% vs 12.5%, P=0.032). Mean duration from chemotherapy onset to the time of liver resection was 11 cycles (range 4-12) in Group A and 8 cycles (range 8-16) in Group B.

CONCLUSION

This study showed that tailored-chemotherapy based on ATP-CRA could improve the treatment response and resectability in initially unresectable colorectal liver metastasis.

Peritoneal carcinomatosis from ovarian cancer: chemosensitivity test and tissue markers as predictors of response to chemotherapy

Background

Platinum-based regimens are the treatments of choice in ovarian cancer, which remains the leading cause of death from gynecological malignancies in the Western world. The aim of the present study was to compare the advantages and limits of a conventional chemosensitivity test with those of new biomolecular markers in predicting response to platinum regimens in a series of patients with peritoneal carcinomatosis from ovarian cancer.

Methods

Fresh surgical biopsy specimens were obtained from 30 patients with primary or recurrent peritoneal carcinomatosis from ovarian cancer. ERCC1, GSTP1, MGMT, XPD, and BRCA1 gene expression levels were determined by Real-Time RT-PCR. An in vitro chemosensitivity test was used to define a sensitivity or resistance profile to the drugs used to treat each patient.

Results

MGMT and XPD expression was directly and significantly related to resistance to platinum-containing treatment (p = 0.036 and p = 0.043, respectively). Significant predictivity in terms of sensitivity and resistance was observed for MGMT expression (75.0% and 72.5%, respectively; p = 0.03), while high predictivity of resistance (90.9%) but very low predictivity of sensitivity (37.5%) (p = 0.06) were observed for XPD. The best overall and significant predictivity was observed for chemosensitivity test results (85.7% sensitivity and 91.3% resistance; p = 0.0003).

Conclusions

The in vitro assay showed a consistency with results observed in vivo in 27 out of the 30 patients analyzed. Sensitivity and resistance profiles of different drugs used in vivo would therefore seem to be better defined by the in vitro chemosensitivity test than by expression levels of markers.

ATP assay-guided chemosensitivity testing for gemcitabine with biopsy specimens obtained from unresectable pancreatic cancer using endoscopic ultrasonography-guided fine-needle aspiration

OBJECTIVES

This study evaluates the feasibility of chemosensitivity testing by use of endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) samples and determines the optimum cut-off value for gemcitabine.

METHODS

Thirty-four consecutive patients with unresectable pancreatic cancer were enrolled. Chemosensitivity (treated/control ratio: T/C ratio) was calculated as the quantity of adenosine triphosphate for a tumor treated with gemcitabine as a percentage of that for the control. To identify the cut-off value sufficient to predict 180 days of progression-free survival (PFS), the receiver operating characteristic curve and the corresponding area under the curve (AUC) were calculated.

RESULTS

The success of this assay was 88.2% (30/34); therefore, 30 patients were assessable and included in the population of analyzable patients.. The response was 6.7%. Median PFS was 96 days and median overall survival was 241 days, respectively. The cut-off value was determined as 74% (AUC, 0.745; p = 0.053; 95% CI 0.485-1.005). According to this cut-off value, we predicted 180 days PFS with a sensitivity and specificity of 71.4 and 91.3%, respectively. When patients were divided into two groups at T/C ratio 74%, a significant difference was found in PFS (median 77 vs. 205 days, p = 0.0036). Moreover, T/C ratio < 74% and decrease of CA19-9 were significant and independent prognostic factors by multivariate analysis.

CONCLUSION

Chemosensitivity testing by use of EUS-FNA samples in patients with unresectable pancreatic cancer is feasible. This definition emphasizes the possibility of selecting patients for whom favorable results from gemcitabine treatment can be expected.

Individualized tumor response testing for prediction of response to Paclitaxel and Cisplatin chemotherapy in patients with advanced gastric cancer

The purpose of our study was to determine the most accurate analytic method to define in vitro chemosensitivity, using clinical response as reference standard in prospective clinical trial, and to assess accuracy of adenosine triphosphate-based chemotherapy response assay (ATP-CRA). Forty-eight patients with chemo-naïve, histologically confirmed, locally advanced or metastatic gastric cancer were enrolled for the study and were treated with combination chemotherapy of paclitaxel 175 mg/m(2) and cisplatin 75 mg/m(2) for maximum of six cycles after obtaining specimen for ATP-CRA. We performed the receiver operator characteristic curve analysis using patient responses by WHO criteria and ATP-CRA results to define the method with the highest accuracy. Median progression free survival was 4.2 months (95% confidence interval [CI]: 3.4-5.0) and median overall survival was 11.8 months (95% CI: 9.7-13.8) for all enrolled patients. Chemosensitivity index method yielded highest accuracy of 77.8% by ROC curve analysis, and the specificity, sensitivity, positive and negative predictive values were 95.7%, 46.2%, 85.7%, and 75.9%. In vitro chemosensitive group showed higher response rate (85.7% vs. 24.1%) (P=0.005) compared to chemoresistant group. ATP-CRA could predict clinical response to paclitaxel and cisplatin chemotherapy with high accuracy in advanced gastric cancer patients. Our study supports the use of ATP-CRA in further validation studies.

Complete response of anaplastic pancreatic carcinoma to paclitaxel treatment selected by chemosensitivity testing

A 58-year-old woman was admitted to our institute in June 2007 because of obstructive jaundice. A mass in the pancreatic head and multiple swollen lymph nodes surrounding the common hepatic artery were identified using computed tomography (CT). Subsequently, endoscopic ultrasonography-guided fine-needle aspiration biopsy (EUS-FNA) was done. Histopathologic results revealed anaplastic carcinoma of the pancreas. Using specimens obtained with EUS-FNA, chemosensitivity testing with adenosine triphosphate assay was performed. Testing indicated high chemosensitivity to paclitaxel (PTX). According to this result, chemotherapy using PTX was performed, and the primary lesion and lymph node metastases disappeared completely on CT. The patient has been doing well with no recurrence for 1 year and 11 months since initial chemotherapy.

Impact of grade, hormone receptor, and HER-2 status in women with breast cancer on response to specific chemotherapeutic agents by in vitro adenosine triphosphate-based chemotherapy response assay

This study was designed to assess whether histological and biological factors of breast cancer can predict chemoresponse to specific agents. Adenosine triphosphate-based chemotherapy response assay (ATP-CRA) was employed to retrieve chemoresponse to 5-fluorouracil (5-FU), doxetaxel, doxorubicin, epirubicin, and paclitaxel in 49 patients. Tumors with high histologic and nuclear grade have higher response rate to doxorubicin (P<0.05) and palitaxel (P<0.05). Estrogen receptor (ER)-negative tumors respond well to doxorubicin (P=0.038), and progesterone receptor (PR)-negative tumors to 5-FU (P=0.039), doxetaxel (P=0.038), doxorubicin (P=0.000), epirubicin (P=0.010), and paclitaxel (P=0.003). Among the breast cancer subtypes determined by ER, PR, and HER-2 immunohistochemical stains, the HER-2+/ER- subtype has a higher response rate to doxorubicin (P=0.008). This in vitro result suggests that the combination of histologic and nuclear grade, hormone receptor, and HER-2 status can be a predictive factor of response to specific chemotherapy agents. Further in vivo study should be followed for clinical trials.

The predictive role of E-cadherin and androgen receptor on in vitro chemosensitivity in triple-negative breast Cancer

OBJECTIVE

The purpose of this study was to evaluate the impact of various pathologic and biologic factors in triple-negative breast cancer (TNBC) on chemotherapy response using in vitro ATP-based chemotherapy response assay (ATP-CRA).

METHODS

Forty-seven cases of TNBC were included. Immunohistochemical stains for androgen receptor (AR), p53, CD10, c-kit, CK5/6, vimentin, bcl-2, E-cadherin, Ki-67 and epidermal growth factor receptor were performed. In vitro ATP-CRA was used to analyze chemosensitivity for 5-fluorouracil (5-FU), docetaxel, doxorubicin, epirubicin, vinorelbine, gemcitabine, methotrexate (MTX), oxaliplatin and paclitaxel.

RESULTS

The results showed that all cytotoxic agents demonstrated the trend that E-cadherin-expressing cases had a higher cell death rate than E-cadherin-negative cases. Particularly, vinorelbine showed statistical significance (P = 0.004). Cases with AR expression showed higher cell death rates than those without in 5-FU and MTX (P = 0.012 and 0.014, respectively).

CONCLUSIONS

E-cadherin and AR could be candidate predictive factors for chemotherapy response in TNBC. Further in vivo study is required to clarify their roles.