The expression of ERCC1, RRM1, and BRCA1 in breast cancer according to the immunohistochemical phenotypes

New Biomarkers and Treatment Advances in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a specific subtype of breast cancer lacking hormone receptor expression and HER2 gene amplification. TNBC represents a heterogeneous subtype of breast cancer, characterized by poor prognosis, high invasiveness, high metastatic potential, and a tendency to relapse. In this review, the specific molecular subtypes and pathological aspects of triple-negative breast cancer are illustrated, with particular attention to the biomarker characteristics of TNBC, namely: regulators of cell proliferation and migration and angiogenesis, apoptosis-regulating proteins, regulators of DNA damage response, immune checkpoints, and epigenetic modifications. This paper also focuses on omics approaches to exploring TNBC, such as genomics to identify cancer-specific mutations, epigenomics to identify altered epigenetic landscapes in cancer cells, and transcriptomics to explore differential mRNA and protein expression. Moreover, updated neoadjuvant treatments for TNBC are also mentioned, underlining the role of immunotherapy and novel and targeted agents in the treatment of TNBC.

Current progress in chimeric antigen receptor-modified T cells for the treatment of metastatic breast cancer

Breast cancer is the leading cancer in women. Around 20-30% breast cancer patients undergo invasion or metastasis after radical surgical resection and eventually die. Number of breast cancer patients show poor sensitivity toward treatments despite the advances in chemotherapy, endocrine therapy, and molecular targeted treatments. Therapeutic resistance and tumor recurrence or metastasis develop with the ongoing treatments. Conducive treatment strategies are thus required. Chimeric antigen receptor (CAR)-modified T-cell therapy has progressed as a part of tumor immunotherapy. However, CAR-T treatment has not been effective in solid tumors because of tumor microenvironment complexity, inhibitory effects of extracellular matrix, and lacking ideal tumor antigens. Herein, the prospects of CAR-T cell therapy for metastatic breast cancer are discussed, and the targets for CAR-T therapy in breast cancer (HER-2, C-MET, MSLN, CEA, MUC1, ROR1, EGFR) at clinical level are reviewed. Moreover, solutions are proposed for the challenges of breast cancer CAR-T therapy regarding off-target effects, heterogeneous antigen expression by tumor cells and immunosuppressive tumor microenvironment. Ideas for improving the therapeutics of CAR-T cell therapy in metastatic breast cancer are suggested.

ERCC1 is a potential biomarker for predicting prognosis, immunotherapy, chemotherapy efficacy, and expression validation in HER2 over-expressing breast cancer

Objective

To investigate the relationship between Excision repair cross-complementation 1 (ERCC1) expression, clinicopathological features, and breast cancer prognosis in patients treated with trastuzumab. Further, we aim to explore the immune status of ERCC1 in breast cancer.

Methods

The data were retrieved from publicly available databases like the Cancer Genome Atlas, Therapeutically Applicable Research to Generate Effective Treatments, and the Genotype-Tissue Expression. The data was used to perform differential expression analyses between tumor and normal tissues in pan-cancers, immune-related analysis, homologous recombination deficiency (HRD), tumor mutation burden, and microsatellite instability. A total of 210 patients with HER2 over-expressing breast cancer from the Fourth Hospital of Hebei Medical University between January 2013 to December 2015 were enrolled in the study. Ten adjacent normal tissues were used to study the expression pattern of ERCC1 in normal tissues. Immunohistochemistry was performed to study ERCC1 expression and immune cell infiltration in different status of ERCC1 expression. Further, the correlation between ERCC1 expression, immune cell infiltration clinicopathological features, and the prognosis of patients with breast cancer was analyzed.

Results

The immune analysis revealed a significant correlation between CD8+ T cell, CD4+ T cell, T helper cell, macrophages, mast cells, and ERCC1 expression. Spearman analysis show that ERCC1 expression is related to macrophages and T cells. A close correlation was observed between increased ERCC1 expression and high tumor immune dysfunction and exclusion (TIDE) score as well as HRD. The results revealed a significant correlation among ERCC1, chemotherapy and estrogen receptor (ER; P < 0.05) expression. Univariate survival analysis revealed a significant correlation (P < 0.05) between that ERCC1 and ER expression, blood vessel invasion, and disease-free survival (DFS). ERCC1 and ER expression, tumor size, blood vessel invasion, pathological type, and lymph node metastases significantly correlated (P < 0.05) with overall survival in patients. Multivariate regression analysis revealed that ERCC1 expression and chemotherapy were independent factors that influence DFS. ERCC1 expression and vascular tumor thrombus were independent influencing factors that influence OS.

Conclusion

A correlation was observed between high ERCC1 expression and poor patient prognosis. High ERCC1 expression also influences the efficacy of immunotherapy and chemotherapy.

Characterization of the HER2 status in BRCA-mutated breast cancer: a single institutional series and systematic review with pooled analysis

BACKGROUND

Pathogenic variants (PVs) in BRCA1/2 genes account for ∼6% of breast and 20% of ovarian cancers. Most breast tumors developed by BRCA1 carriers are triple negative. BRCA2 tumors have similar rates of estrogen receptor positivity as sporadic controls but are less likely to be human epidermal growth factor receptor 2 (HER2)-positive. Prevalence of HER2 positivity among breast cancers (BCs) in BRCA1/2 mutation carriers is poorly and variably described, ranging from 0% to 10% and 0% to 13% in BRCA1 and BRCA2 carriers, respectively.

PATIENTS AND METHODS

We assessed the prevalence of HER2 positivity among a single institutional cohort of 398 BCs developed in carriers of BRCA1/2 PVs (240 BRCA1, 158 BRCA2). Subsequently, a systematic review of the literature and pooled analysis was carried out.

RESULTS

In our series we found a 7% HER2 positivity rate among all first BRCA1/2 BCs overall. In BRCA1 carriers, 5.4% of BCs were HER2-positive compared with 9.5% in BRCA2-mutated patients. Among bilateral BCs, HER2-positive cases were 15.2% in the BRCA1 group and 23.1% in the BRCA2 group. Notably, six BRCA1 and eight BRCA2 carriers showed discordant HER2 status between BC and bilateral BC (23.7%, 14/59). The systematic review included 21 083 BRCA1/2 patients from 73 eligible studies. The pooled rate of BRCAmut/HER2-positive BCs is 9.1% (95% confidence interval 7.3% to 11.2%). BRCA1 and BRCA2 when reported as separate data ranged from 0% to 33.3% (mean 8.3%) and from 0% to 86% (mean 10.3%), respectively.

CONCLUSIONS

As compared with sporadic cases, BCs occurring in BRCA1 and/or BRCA2 PVs carriers are less frequently HER2-positive. Prevalence of HER2 positivity in our series was consistent with pooled analysis and did not exceed 10%. Although not common, co-existence of BRCA mutations and HER2 overexpression and/or gene amplification should be acknowledged. More research is needed to better characterize this subgroup of patients who should not be excluded a priori from clinical trials of targeted therapy for BRCA1/2-driven cancers.

Expression of HER2 and BRCA1 Correlates with Prognosis in Patients with Breast Cancer After Radiotherapy: A Case-Control Study

Background: This study aims to explore the associations of human epidermal growth factor receptor 2 (HER2) and breast cancer susceptibility gene 1 (BRCA1) expression levels with prognosis and radiation sensitivity in patients with breast cancer. Methods: Breast cancer tissues, adjacent normal breast tissues, and benign breast lesions were initially obtained from 256 breast cancer patients as well as an additional 245 patients with breast lesions. Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) was conducted to assess the expression of HER2 and BRCA1 in the collected tissues. Immunohistochemistry was performed to examine HER2 and BRCA1-positive expression levels in the tissues. The relationship between HER2 and BRCA1 expression levels and radiation sensitivity as well breast cancer prognosis was assessed by the Spearman correlation analysis and Kaplan-Meier survival analysis. Results: Compared with adjacent normal breast tissues and benign breast lesions, the breast cancer tissues exhibited high expression of HER2 mRNA and protein and low expression of BRCA1 mRNA and protein. Patients with positive HER2 expression had a significantly shorter survival time, and survival time of patients with positive BRCA1 expression was markedly longer, which were consistent with RT-qPCR results. After radiotherapy, the local failure rate of HER2-positive patients was higher than that of the negative ones, while that of BRCA1-positive patients was lower than that of the negative ones. Conclusions: This study suggested that breast cancer patients with high HER2 expression and low BRCA1 expression were less sensitive to radiotherapy with poor prognosis in breast cancer.

Identification of protein targets and the mechanism of the cytotoxic action of Ipomoea turpethum extract loaded nanoparticles against breast cancer cells

The shortcomings of the currently available anti-breast cancer agents compel the development of the safer targeted drug delivery for the treatment of breast cancer. The aim of the present study was to evaluate the anti-breast cancer potential of Ipomoea turpethum extract loaded nanoparticles (NIPAAM-VP-AA) against breast cancer, together with the identification of the key proteins responsible for the caused cytotoxicity. For this, we explored the tumor microenvironment for targeted drug delivery and synthesized (temperature and pH responsive) double triggered polymeric nanoparticles by the free radical mechanism and characterized them by DLS and TEM. The extract which emerged as the best extract, i.e. root extract, was loaded on the nanoparticles and the cytotoxicity was evaluated in breast cancer cell lines (MCF-7 and MDA-MB-231) by various cytotoxic assays like MTT assay, CFSE cell proliferation assay, apoptosis assay, cell cycle study and DAPI nuclear staining. The key protein targets responsible for the caused cytotoxicity were identified by nano-LC-MS/MS analysis. The proteome analysis revealed that most of the significantly differentially expressed proteins have a role in proliferation, vesicular trafficking, apoptosis and tumor suppression. Finally, the interaction among the highly differentially expressed proteins was identified by using the STRING online tool, which showed that I. turpethum nanoparticles caused apoptosis in MCF-7 and MDA MB-231 cells by targeting nucleolysin TIAR, serine/threonine-protein phosphatase PP1 and ubiquitin-60S ribosomal protein L40.

EGFR-targeted CAR-T cells are potent and specific in suppressing triple-negative breast cancer both in vitro and in vivo

Objectives

Triple-negative breast cancer (TNBC) is well known for its strong invasiveness, rapid recurrence and poor prognosis. Immunotherapy, including chimeric antigen receptor-modified T (CAR-T) cells, has emerged as a promising tool to treat TNBC. The identification of a specific target tumor antigen and the design of an effective CAR are among the many challenges of CAR-T therapy.

Methods

We reported that epidermal growth factor receptor (EGFR) is highly expressed in TNBC and consequently designed an optimal third generation of CAR targeting EGFR. The efficacy of primary T lymphocytes infected with EGFR CAR lentivirus (EGFR CAR-T) against TNBC was evaluated both in vitro and in vivo. The signalling pathways activated in tumor and EGFR CAR-T cells were revealed by RNA sequencing analysis.

Results

Third-generation EGFR CAR-T cells exerted potent and specific suppression of TNBC cell growth in vitro, whereas limited cytotoxicity was observed towards normal breast epithelial cells or oestrogen receptor-positive breast cancer cells. This capability was further demonstrated in vivo in a xenograft mouse model, with minimal off-tumor cytotoxicity. Mechanistically, in vitro stimulation with TNBC cells induced the expansion of naïve-associated EGFR CAR-T cells and enhanced their persistence. Furthermore, EGFR CAR-T cells activated the interferon γ, granzyme-perforin-PARP and Fas-FADD-caspase signalling pathways in TNBC cells.

Conclusion

We demonstrate that EGFR is a relevant immunotherapeutic target in TNBC, and EGFR CAR-T exhibits potent and specific antitumor activity against TNBC, suggesting the potential of this third-generation EGFR CAR-T as an immunotherapy tool to treat TNBC in the clinic.

Pharmacogenetics of toxicity of 5-fluorouracil, doxorubicin and cyclophosphamide chemotherapy in breast cancer patients

The differences in patients' response to the same medication, toxicity included, are one of the major problems in breast cancer treatment. Chemotherapy toxicity makes a significant clinical problem due to decreased quality of life, prolongation of treatment and reinforcement of negative emotions associated with therapy. In this study we evaluated the genetic and clinical risk factors of FAC chemotherapy-related toxicities in the group of 324 breast cancer patients. Selected genes and their polymorphisms were involved in FAC drugs transport (ABCB1, ABCC2, ABCG2,SLC22A16), metabolism (ALDH3A1, CBR1, CYP1B1, CYP2C19, DPYD, GSTM1, GSTP1, GSTT1, MTHFR,TYMS), DNA damage recognition, repair and cell cycle control (ATM, ERCC1, ERCC2, TP53, XRCC1). The multifactorial risk models that combine genetic risk modifiers and clinical characteristics were constructed for 12 toxic symptoms. The majority of toxicities was dependent on the modifications in components of more than one pathway of FAC drugs, while the impact level of clinical factors was comparable to the genetic ones. For the carriers of multiple high risk factors the chance of developing given symptom was significantly elevated which proved the factor-dosage effect. We found the strongest associations between concurrent presence of clinical factors - overall and recurrent anemia, nephrotoxicity and early nausea and genetic polymorphisms in genes responsible for DNA repair, drugs metabolism and transport pathways. These results indicate the possibility of selection of the patients with expected high tolerance to FAC treatment and consequently with high chance of chemotherapy completion without the dose reduction, treatment delays and decline in the quality of life.

High excision repair cross-complementation group 1 expression is associated with favorable prognostic factors in breast cancer

Distortion of DNA can inhibit transcription and replication, resulting in cell death. The nucleotide excision repair (NER) pathway recognizes and repairs DNA adducts. Excision repair cross-complementation group 1 (ERCC1) is a nuclease that serves a vital role in the NER pathway. Few studies have investigated ERCC1 expression in breast cancer. The aim of the present study was to analyze the association between clinicopathological features and ERCC1 expression in breast cancer. ERCC1 expression was studied in 224 invasive ductal carcinomas by immunohistochemical staining. ERCC1 expression was analyzed as an immunoreactive score, and classified into low and high expression groups. The association between immunohistochemical parameters and clinicopathological features was evaluated. High expression of ERCC1 was observed in 33 cases (14.7%) and was statistically associated with lower T stage (P=0.005), lower tumor size (P=0.001), no lymph node metastasis (P=0.044) and no lymphovascular invasion (LVI; P=0.004). Additionally, high ERCC1 expression was associated with a positive estrogen receptor (ER) (P=0.006) and progesterone receptor (PR) (P=0.001) expression status. Non-triple-negative breast carcinoma occurred more frequently in the high expression group (97%) than the low expression group; however, the difference was not statistically significant (P=0.056). Overall and disease-free survival were also not significantly different between the two groups (P=0.989 and P=0.215, respectively). In conclusion, high ERCC1 expression is statistically associated with lower T stage, smaller tumor size, no lymph node metastasis, no LVI, and positive ER and PR expression. This suggests that ERCC1 is associated with favorable prognostic parameters in breast cancer.

ERCC1 Expression in Metastatic Triple Negative Breast Cancer Patients Treated with Platinum-Based Chemotherapy

Background: Possible targeted therapies for metastatic triple negative breast cancer (TNBC) include cytotoxic chemotherapy that causes interstrand breaks (platinum-based drugs). The excision repair cross-complementation 1 (ERCC1) enzyme plays an essential role in the nucleotide excision repair pathway, removing platinum-induced DNA adducts and contributing to cisplatin resistance. Detecting ERCC1 overexpression is important in considering treatment options for metastatic TNBC, including individualized approaches to therapy, and may facilitate improved responses or reduction of unnecessary toxicity. We hypothesized that assigning cisplatin based on pretreatment ERCC1 expression would improve response and survival. This study was conducted to assess the impact of ERCC1 expression on PFS, OS and response rates in metastatic triple negative breast cancer patients treated with platinum-based chemotherapy. Methods: From June 2012 to November 2013, 52 metastatic triple negative breast cancer patients were enrolled. ERCC1 protein expression was detected from pretreatment biopsies by Immunohistochemistry. All patients received cisplatin plus paclitaxel. The primary end point was the impact of ERCC1 expression on PFS and OS. Results: 34 patients (65.4%) showed positive ERCC1 expression while 18 (34.6%) proved negative. Positive ERCC1 expression was associated with short PFS (median, 5 months vs. 7 months; P = 0.043), short OS (median, 9 months vs. 11 months; P = 0.033) and poor response to cisplatin based chemotherapy (P = 0.046). Conclusions: This prospective study further validated ERCC1 as a reliable biomarker for customized chemotherapy in metastatic triple negative breast cancer patients. High expression of ERCC1 was thereby fond to be significantly associated with poor outcome in patients treated with platinum based chemotherapy.

Effect of low doses of estradiol and tamoxifen on breast cancer cell karyotypes

Evidence supports a role of 17&-estradiol (E2) in carcinogenesis and the large majority of breast carcinomas are dependent on estrogen. The anti-estrogen tamoxifen (TAM) is widely used for both treatment and prevention of breast cancer; however, it is also carcinogenic in human uterus and rat liver, highlighting the profound complexity of its actions. The nature of E2- or TAM-induced chromosomal damage has been explored using relatively high concentrations of these agents, and only some numerical aberrations and chromosomal breaks have been analyzed. This study aimed to determine the effects of low doses of E2 and TAM (10(&8 )mol L(&1) and 10(&6 )mol L(&1) respectively) on karyotypes of MCF7, T47D, BT474, and SKBR3 breast cancer cells by comparing the results of conventional karyotyping and multi-FISH painting with cell proliferation. Estrogen receptor (ER)-positive (+) cells showed an increase in cell proliferation after E2 treatment (MCF7, T47D, and BT474) and a decrease after TAM treatment (MCF7 and T47D), whereas in ER& cells (SKBR3), no alterations in cell proliferation were observed, except for a small increase at 96 h. Karyotypes of both ER+ and ER& breast cancer cells increased in complexity after treatments with E2 and TAM leading to specific chromosomal abnormalities, some of which were consistent throughout the treatment duration. This genotoxic effect was higher in HER2+ cells. The ER&/HER2+ SKBR3 cells were found to be sensitive to TAM, exhibiting an increase in chromosomal aberrations. These in vitro results provide insights into the potential role of low doses of E2 and TAM in inducing chromosomal rearrangements in breast cancer cells.

ERCC1 and telomere status in breast tumours treated with neoadjuvant chemotherapy and their association with patient prognosis

Dysfunctional telomeres and DNA damage repair (DDR) play important roles in cancer progression. Studies have reported correlations between these factors and tumour aggressiveness and clinical outcome in breast cancer. We studied the characteristics of telomeres and expression of ERCC1, a protein involved in a number of DNA repair pathways and in telomere homeostasis, to assess their prognostic value, alone or in combination, in 90 residual breast tumours after treatment with neoadjuvant chemotherapy (NCT). ERCC1 status was investigated at different molecular levels (protein and gene expression and gene copy‐number variations) by immunohistochemistry, qRT‐PCR and quantitative multiplex fluorescent‐PCR (QMF‐PCR). A comprehensive analysis of telomere characteristics was performed using qPCR for telomere length and qRT‐PCR for telomerase (hTERT), tankyrase 1 (TNKS) and shelterin complex (TRF1, TRF2, POT1, TPP1, RAP1 and TIN2) gene expression. Short telomeres, high hTERT and TNKS expression and low ERCC1 protein expression were independently associated with worse survival outcome. Interestingly, ERCC1 gains and losses correlated with worse disease‐free (p = 0.026) and overall (p = 0.043) survival as compared to survival of patients with normal gene copy‐numbers. Unsupervised hierarchical clustering of all ERCC1 and telomere parameters identified four subgroups with distinct prognosis. In particular, a cluster combining low ERCC1, ERCC1 gene alterations, dysfunctional telomeres and high hTERT and a cluster with high TNKS and shelterin expression correlated with poor disease‐free (HR= 5.41, p= 0.0044) and overall survival (HR= 6.01, p= 0.0023) irrespective of tumour stage and grade. This comprehensive study demonstrates that telomere dysfunction and DDR can contribute synergistically to tumour progression and chemoresistance. These parameters are predictors of clinical outcome in breast cancer patients treated with NCT and could be useful clinically as prognostic biomarkers to tailor adjuvant chemotherapy post‐NCT.

alphaB-crystallin is a marker of aggressive breast cancer behavior but does not independently predict for patient outcome: a combined analysis of two randomized studies

BACKGROUND

alphaB-crystallin is a small heat shock protein that has recently been characterized as an oncoprotein correlating with the basal core phenotype and with negative prognostic factors in breast carcinomas. The purpose of this study was to evaluate alphaB-crystallin with respect to clinicopathological parameters and the outcome of patients with operable high-risk breast cancer.

METHODS

A total of 940 tumors were examined, derived from an equal number of patients who had participated in two randomized clinical trials (paclitaxel-containing regimen in 793 cases). Immunohistochemistry for ER, PgR, HER2, Ki67, CK5, CK14, CK17, EGFR, alphaB-crystallin, BRCA1 and p53 was performed. BRCA1 mutation data were available in 89 cases.

RESULTS

alphaβ-crystallin was expressed in 170 cases (18.1%) and more frequently in triple-negative breast carcinomas (TNBC) (45% vs. 14.5% non-TNBC, p < 0.001). alphaB-crystallin protein expression was significantly associated with high Ki67 (Pearson chi-square test, p < 0.001), p53 (p = 0.002) and basal cytokeratin protein expression (p < 0.001), BRCA1 mutations (p = 0.045) and negative ER (p < 0.001) and PgR (p < 0.001). Its overexpression, defined as >30% positive neoplastic cells, was associated with adverse overall survival (Wald's p = 0.046). However, alphaB-crystallin was not an independent prognostic factor upon multivariate analysis. No interaction between taxane-based therapy and aβ-crystallin expression was observed.

CONCLUSIONS

In operable high-risk breast cancer, alphaB-crystallin protein expression is associated with poor prognostic features indicating aggressive tumor behavior, but it does not seem to have an independent impact on patient survival or to interfere with taxane-based therapy.

TRIAL REGISTRATIONS

ACTRN12611000506998 (HE10/97 trial) and ACTRN12609001036202 (HE10/00 trial).

Clinicopathological features and prognostic factors of young breast cancers in Eastern Guangdong of China

Breast cancer in young women is typically with higher proportion of adverse pathological features. Breast cancer with BRCA1 mutation is often early-onset, and is usually associated with triple negative phenotpe. In this study, we aim to analyze the clinicopathological characteristics and prognosis in young breast cancer patients (≤35 years old) comparing to non-young patients (>35 years old). A total of 1913 cases of primary breast carcinoma with stage I-III were enrolled, with 283 cases diagnosed as young patients. No significant difference was observed in tumor size, TNM staging, lymph node metastasis, ER, HER-2 or histological grade between young and non-young patients. Multivariate analysis demonstrated that age was an independent prognostic factor for overall survival (OS). In 70 samples of young patients available, BRCA1 was immunohistochemically positive 85.7% in cytoplasm and 41.4% in nuclear. BRCA1 nuclear expression is not significantly associated with clinicopathological characteristics in young breast cancer patients.

Association of novel gene polymorphisms RRM1 -756T>C and -269 C>A with breast cancer

BACKGROUND

Genetic variants are reported to play an important role in the susceptibility of breast cancer. Ribonucleotide reductase 1 (RRM1) is suggested to play an essential role in the regulation of cancer development. The purpose of this study was to identify novel gene polymorphisms of RRM1 -756T>C and RRM1 -269 C>A specific to patients with breast cancer and healthy controls.

METHODS

A total of 833 subjects, including 321 healthy controls and 512 patients with breast cancer, were recruited in this study. Allelic discrimination of RRM1 -756T>C (rs11030919) and RRM1 -269C>A (rs12806698) polymorphisms of the RRM1 gene was assessed with the real-time polymerase chain reaction.

RESULTS

The adjusted odds ratios and 95% confidence intervals were 1.20 (0.71-2.04) and 1.10 (0.65-1.86) to have breast cancer among individuals with CC alleles of RRM1 -756T>C and individuals with AA alleles of RRM1 -269C>A gene polymorphism, respectively, compared to individuals having wild type of RRM1 gene polymorphisms. Also, there was no significant genetic interaction effect on the susceptibility of breast cancer and nonassociation between genetic polymorphisms and clinical statuses of breast cancer.

CONCLUSION

Gene polymorphisms of RRM1 -756T>C and RRM1 -269C>A may be not an important factor for the susceptibility of breast cancer.

Gemcitabine and carboplatin demonstrate synergistic cytotoxicity in cervical cancer cells by inhibiting DNA synthesis and increasing cell apoptosis

BACKGROUND

The present study aims to investigate the subunit expression and enzyme activity of ribonucleotide reductase in cervical cancer patients, and detect the combined effect of the ribonucleotide reductase inhibitor gemcitabine and the chemotherapeutic agent carboplatin on cervical cancer cell lines.

METHODS

Using quantitative reverse transcription polymerase chain reaction, Western blotting, and cytidine 5'-diphosphate reduction assays, we tested the expression and activity of ribonucleotide reductase in cervical cancer patients. The antitumor activity of gemcitabine and/or carboplatin treatments to SiHa and CaSki human cervical cancer cell lines were assessed by Cell Counting Kit-8 viability assay, EdU incorporation assay, immunofluorescence assay, flow cytometry assay, and Western blotting methods. Additionally, synergistic efficacy was quantitatively analyzed using a combination index based on the Chou-Talalay method.

RESULTS

The mRNA levels of three ribonucleotide reductase subunits were all upregulated in the cervical cancer tissues compared with normal tissues (P<0.0001). Consistently, the protein expression and enzyme activity of ribonucleotide reductase were also increased in the cervical cancer tissues. Interestingly, gemcitabine inhibited DNA synthesis and carboplatin induced DNA damage. Further, the combined drug regime had a significant synergistic effect on inhibiting cervical cancer cell viability (log10[combination index] <0) via enhanced DNA damage and cell apoptosis.

CONCLUSION

The expression and activity of ribonucleotide reductase was increased in cervical cancer. Our study demonstrated the synergistic cytotoxicity of gemcitabine and carboplatin, through inhibiting DNA synthesis and increasing cell apoptosis in cervical cancer cell lines. This evidence might provide a rational clue of their combined application to improve cervical cancer treatment.

Gene aberrations of RRM1 and RRM2B and outcome of advanced breast cancer after treatment with docetaxel with or without gemcitabine

Background

The purpose of the present study was to retrospectively evaluate whether copy number changes of the genes encoding the ribonucleotide reductase subunit M1 (RRM1) and/or subunit M2B (RRM2B) predict sensitivity to gemcitabine administered in combination with docetaxel compared to single agent docetaxel in advanced breast cancer patients.

Methods

Primary tumor samples from patients randomly assigned to gemcitabine plus docetaxel or docetaxel alone were analyzed for RRM1 and RRM2B copy number changes using Fluorescence In Situ Hybridization (FISH) technology with probes covering respectively RRM1 at 11p15.5 and a reference probe covering the centromere of chromosome 11 (CEN-11), and RRM2B at 8q22.3 and a reference probe covering the centromere of chromosome 8 (CEN-8). The assays were validated in a material of 60 normal breast samples. Time to progression (TTP) was the primary endpoint. Overall survival (OS) and response rate (RR) were secondary endpoints. Associations between RRM1/CEN-11 and/or RRM2B/CEN-8 ratios and time-to-event endpoints were analyzed by unadjusted and adjusted Cox proportional hazards regression models. Heterogeneity of treatment effects on TTP and OS according to gene status were investigated by subgroup analyses, and the Wald test was applied. All statistical tests were two-sided.

Results

FISH analysis for both RRM1 and RRM2B was successful in 251 patients. RRM1 and RRM2B aberrations (deletions and amplifications) were observed in 15.9% and 13.6% of patients, respectively. RRM1 aberrations were associated with a decreased OS in the time interval 1.5-7.4 years (hazard ratio = 1.72, 95% confidence interval = 1.05-2.79, P = 0.03). RRM2B aberrations alone or in combination with RRM1 aberrations had no prognostic impact in terms of TTP or OS. RR was not different by gene status. No significant differences were detected in TTP or OS within subgroups according to gene status and chemotherapy regimen.

Conclusions

This study demonstrated the presence of RRM1 and RRM2B copy number changes in primary breast tumor specimens. Nevertheless, we found no support of the hypothesis that aberrations of RRM1 or RRM2B, neither individually nor in combination, are associated with an altered clinical outcome following chemotherapy with gemcitabine in combination with docetaxel compared to docetaxel alone in advanced breast cancer patients.

FOXP3 expression is related to high Ki-67 index and poor prognosis in lymph node-positive breast cancer patients

BACKGROUND

Recent preclinical studies have shown that Forkhead box protein 3 (FOXP3) is an important tumor suppressor gene. The clinical and prognostic implication of FOXP3 expression in breast cancer cells still remains controversial.

METHODS

We evaluated the FOXP3 expression status of 183 patients who underwent curative surgery for breast cancer using the immunohistochemical assay of tissue microarray.

RESULTS

We found FOXP3 expression in 51 out of 183 (27.9%) surgically resected breast cancer tumors, and 33 patients were scored as weak positive and 18 as strong positive. FOXP3-positive tumors were associated with significantly higher nuclear grade, higher histologic grade and a more negative estrogen receptor status. The FOXP3 expression level was independently associated with high Ki-67 index in a logistic regression model. In the node-positive subgroup, strong FOXP3 positivity was related to poor disease-free survival and disease-specific survival compared to FOXP3-negative patients, whereas there was no survival difference between FOXP3-negative and FOXP3-weak-positive patients. Multivariate analysis with adjustment for patient age and human epidermal growth factor receptor 2 status demonstrated significantly poor survival of FOXP3-strong-positive patients in node-positive patients.

CONCLUSION

Our results suggest that strong FOXP3 expression in breast cancer cells is associated with poor prognosis and high Ki-67 index.

Neoadjuvant treatments for triple-negative breast cancer (TNBC)

Neoadjuvant chemotherapy provides a means both of improving subsequent surgical intervention and of testing novel therapies or combinations. Historically, triple-negative breast cancer (TNBC) has responded well in the neoadjuvant setting, with rates of pathological complete response (pCR) commonly higher than for other breast tumour types. However, more than half of TNBC patients do not achieve a pCR and have a very poor prognosis. The lack of drug-targetable receptors on TNBC tumours has made improving the available interventions in TNBC an area of important medical need. The routine use of neoadjuvant anthracycline/taxane combinations in TNBC is currently being supplemented by ongoing investigations of their use with other types of agent. In particular, the substantial proportion of TNBC tumours associated with BRCA1 mutations is driving clinical research into the use of DNA-damaging agents such as platinums, as well as of potentiators of DNA damage such as the investigational agent iniparib and inhibitors of poly-ADP ribose polymerase such as olaparib. Tyrosine kinase receptor inhibitors and microtubule-targeting inhibitors of cell cycling are also under active investigation. The use of neoadjuvant treatment with pCR as a surrogate of overall survival will allow the rapid evaluation and comparison of these and other much-needed new treatments for TNBC.

Clinicopathological significance of ERCC1 expression in breast cancer

The excision repair cross-complementation 1 (ERCC1) enzyme plays an essential role in the nucleotide excision repair pathway and is associated with resistance to platinum-based chemotherapy in different types of cancer. The aim of the present study was to evaluate the clinicopathological significance of ERCC1 expression in breast cancer patients. We analyzed the immunohistochemical expression of ERCC1 in a tissue microarray from 135 primary breast carcinomas and correlated the immunohistochemical findings with clinicopathological factors and outcome data. ERCC1 expression analysis was available for 109 cases. In this group, 58 (53.2%) were positive for ERCC1. ERCC1-positive expression was correlated with smaller tumor size (P=0.007) and with positivity for estrogen receptor (P=0.040), but no correlation was found with other clinicopathological features. Although not statistically significant, triple negative breast cancers were more frequently negative for ERCC1 (61.5% of the cases) compared to the non-triple negative breast cancer cases (41.5%). In conclusion, ERCC1 expression correlated significantly with favorable prognostic factors, such as smaller tumor size and ER-positivity, suggesting a possible role for ERCC1 as a predictive and/or prognostic marker in breast cancer.

Emodin affects ERCC1 expression in breast cancer cells

Background

Multi-drug resistance to chemotherapeutic agents is a major cause of treatment failure in breast cancer. In this study, we investigated the effects of emodin on reversing the multi-drug resistance, examined the ERCC1 protein expression in breast cancer cell line, and explored the relationship between reversal of multi-drug resistance and ERCC1 protein expression.

Methods

MTT assay was conducted to test the cytotoxicity of adriamycin and cisplatin to MCF-7/Adr cells with and without emodin pretreatment, and Western blot was performed to examine the ERCC1 protein expression.

Results

MCF-7/Adr cells had 21-fold and 11-fold baseline resistances to adriamycin and cisplatin, respectively. When emodin was added to the cell culture at the concentration of 10 μg/ml, the drug resistance was reduced from 21 folds to 2.86 folds for adriamycin, and from 11 folds to 1.79 folds for cisplatin. MCF-7/Adr cells treated with two concentrations (10μg/mL and 20μg/mL) of emodin, after 2, 4, 6, 10 days, the trend of ERCC1 expression was gradually decreased and the reduction was more obvious comparatively at the concentration of 20μg/mL.

Conclusions

Emodin could reverse the multi-drug resistance in MCF-7/Adr cells and down-regulate ERCC1 protein expression.

ERCC1 intron 1 was associated with breast cancer risk

INTRODUCTION

There are numerous studies addressing associations of polymorphisms in DNA repair genes and cancer risks because accurate and efficient DNA repair is crucial to genomic integrity and fidelity. ERCC1 is important in DNA nucleotide excision repair.

MATERIAL AND METHODS

We genotyped constitutive variants of ERCC1 in approximately 300 adults with breast adenocarcinoma and 126 controls of Iranian women. In total, 426 Iranian sporadic breast cancer affected women compared to the control group were studied by PCR-RFLP for ERCC1 variant.

RESULTS

The genotype ERCC1 TT has the highest frequency in both groups (36.6 in patients and 8.5 in controls). The genotype ERCC1 was the most important risk factor in our population [GG/AA odds ratio: 0.692, 95% confidence interval (CI): 0.4-1.199, p = 0.188; GG/AG odds ratio: 3.333, 95% CI: 1.917-5.795, p = 0.001; AA/AG odds ratio: 0.208, 95% CI: 0.124-0.348, p = 0.342].

CONCLUSIONS

Our patients was associated with breast cancer risk.

Clinicopathological study of non-palpable familial breast cancer detected by screening mammography and diagnosed as DCIS

BACKGROUND

Recent widespread use of screening mammography has led to increased detection rates of non-palpable breast cancer. This study aimed to evaluate the clinicopathological features of non-palpable ductal carcinomas in situ of the breast that were detected by screening mammography of patients with a family history of breast cancer.

METHODS

We selected 6 Japanese patients diagnosed with non-palpable breast cancer with self-reported family history of breast cancer. Mutations in BRCA1 and BRCA2 were evaluated with germ line genetic testing and immunohistochemistry (IHC) using resected specimens. Pathological features, such as estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2, were also evaluated.

RESULTS

The patients (ages 41-67 years; mean 53.5) had 7 tumors with one patient having synchronous bilateral breast cancer. Breast cancer was suspected from the microcalcification in 5 tumors and the distortion in 2 tumors by mammography and diagnosed by biopsy. Breast-conserving surgery was performed in 2 patients and mastectomy was performed in 4 patients. Genetic testing revealed BRCA2 gene germ line mutation in three patients. IHC of BRCA was consistent with BRCA2 mutation status.

CONCLUSIONS

The family history of breast cancer patients may lead one to suspect familial breast cancer and screening mammography is useful for the early detection of these cancers. IHC of BRCA showed staining results that were consistent with BRCA genetic testing, suggesting that it has the potential to be a useful tool in clinical practice.

Anti-tumour activity of 4-(4-fluorophenyl)amino-5,6,7-trimethoxyquinazoline against tumour cells in vitro

In order to create novel, potent and selective anti-cancer agents, the action of 4-(4-fluorophenyl)amino-5,6,7-trimethoxyquinazoline (compound 1018) on 10 different kinds of tumour cells were assayed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide]. It possesses a broad spectrum of anti-cancer activity. The mechanism of action of 4-(4-fluorophenyl)amino-5,6,7-trimethoxyquinazoline (hereafter referred to as compound 1018) against tumour cells was studied in androgen-independent prostate cancer PC-3 cells by microscopic observation, LDH (lactate dehydrogenase) release assay and Western blotting. Its activity was dose-dependent, with an IC50 of 13.0±1.4 μM after 72 h treatment. Microscopy and LDH release assay indicated that the effect was through anti-proliferation rather than cytotoxicity. Western blot analysis also showed that treatment of cells with 50 μM compound 1018 for 30 min almost completely inhibited EGF (epidermal growth factor)-induced phosphorylation of ERK1/2 (extracellular-signal-regulated kinase 1/2), which suggests that its anti-proliferative effect is largely associated due to ERK1/2 activation being inhibited. Thus compound 1018 is a potential anti-cancer agent.

Combined analysis of mRNA expression of ERCC1, BAG-1, BRCA1, RRM1 and TUBB3 to predict prognosis in patients with non-small cell lung cancer who received adjuvant chemotherapy

BACKGROUND

The aim of this study was to investigate prognostic value of excision repair cross-complementing 1 (ERCC1), BCL2-associated athanogene (BAG-1), the breast and ovarian cancer susceptibility gene 1 (BRCA1), ribonucleotide reductase subunit M1 (RRM1) and class III β-tubulin (TUBB3) in patients with non-small cell lung cancer (NSCLC) who received platinum- based adjuvant chemotherapy.

METHODS

Messenger RNA expressions of these genes were examined in 85 tumor tissues and 34 adjacent tissue samples using semi-quantitative RT-PCR. The expressions of these five genes were analyzed in relation to chemotherapy and progression-free survival (PFS) and overall survival (OS). Seventy-four patients were enrolled into chemotherapy.

RESULTS

Patients with ERCC1 or BAG-1 negative expression had a significantly longer PFS (P = 0.001 and P = 0.001) and OS (P = 0.001 and P = 0.001) than those with positive expression. Patients with negative ERCC1 and BAG-1 expression benefited more from platinum regimen (P = 0.001 and P = 0.002). Patients with BRCA1 negative expression might have a longer OS (P = 0.052), but not PFS (P = 0.088) than those with BRCA1 positive expression. A significant relationship was observed between the mRNA expression of ERCC1 and BAG-1 (P = 0.042). In multivariate analysis, ERCC1 and BAG-1 were significantly favorable factors for PFS (P = 0.018 and P = 0.017) and OS (P = 0.027 and P = 0.022).

CONCLUSIONS

ERCC1 and BAG-1 are determinants of survival after surgical treatment of NSCLC, and its mRNA expression in tumor tissues could be used to predict the prognosis of NSCLC treated by platinum.

Gene expression and pathologic response to neoadjuvant chemotherapy in breast cancer

Pathologic complete response after neoadjuvant systemic treatment appears to be a valid surrogate for better overall survival in breast cancer patients. Currently, together with standard clinicopathologic assessment, novel molecular biomarkers are being exhaustively tested in order to look into the heterogeneity of breast cancer. The aim of our study was to examine an association between 23-gene real-time-PCR expression assay including ABCB1, ABCC1, BAX, BBC3, BCL2, CASP3, CYP2D6, ERCC1, FOXC1, GAPDH, IGF1R, IRF1, MAP2, MAPK 8, MAPK9, MKI67, MMP9, NCOA3, PARP1, PIK3CA, TGFB3, TOP2A, and YWHAZ receptor status of breast cancer core biopsies sampled before neoadjuvant chemotherapy (anthracycline and taxanes) and pathologic response. Core-needle biopsies were collected from 42 female patients with inoperable locally advanced breast cancer or resectable tumors suitable for downstaging, before any treatment. Expressions of 23 genes were determined by means of TagMan low density arrays. Analysis of variance was used to select genes with discriminatory potential between receptor subtypes. We introduced a correction for false discovery rates (presented as q values) due to multiple hypothesis testing. Statistical analysis showed that seven genes out of a 23-gene real-time-PCR expression assay differed significantly in relation to pathologic response regardless of breast cancer subtypes. Among these genes, we identified: BAX (p = 0.0146), CYP2D6 (p = 0.0063), ERCC1 (p = 0.0231), FOXC1 (p = 0.0048), IRF1 (p = 0.0022), MAP2 (p = 0.0011), and MKI67 (p = 0.0332). The assessment of core biopsy gene profiles and receptor-based subtypes, before neoadjuvant therapy seems to predict response or resistance and to define new signaling pathways to provide more powerful classifiers in breast cancer, hence the need for further research.