Detection of gene expression in sentinel lymph node of primary breast cancer patients

Sentinel lymph node (SLN) micrometstasis detection improves outcome for breast cancer follow up procedure. The aim of the present study was to identify gene profiles that accurately predicted the outcome of breast cancer patients. Fifty tumor sample from breast cancer patients were analyzed for the expression of 3 genes using quantitative-PCR. Also clinical verification for recurrence to distant organs was performed. Three gene signature were confirmed based on tumor's stage, grade, ER status, using conditional logistic regression. Based on this findings, the negative reported lymph nodes for metastasis, had micro metastasis in significant values. There was a significant difference between normal and cancer samples in 3 gene expression marker and also there was meaningful relationship between three gene expression with tumor's grade, stage according to progression of tumor. A novel gene expression signature predictive of micro metastatic patients was evaluated. In this assessment, relationship between this gene with tumor's features   that finding clear role for these genes with tumor's outcome, needs to be established.

Human mammaglobin: A specific marker for breast cancer prognosis

PURPOSE

In this study, we examined the expression of human mammaglobin (hMAM) mRNA and the protein levels in patients with breast cancer and their relationship with prognostic clinicopathological parameters.

METHODS

hMAM mRNA expression in leucocytes from peripheral blood samples from patients diagnosed with primary invasive breast cancer (IC), carcinoma in situ (CIS), or benign breast diseases was analyzed using RT-PCR. The hMAM protein levels and expression patterns in tissue from 3 patient groups were evaluated by immunohistochemical staining, and several non-breast neoplasms were selected as negative controls, undergoing the same examination.

RESULTS

The expression of hMAM mRNA was significantly higher in patients with IC or CIS compared to those with benign tumors (both<0.01). Immunohistochemical staining revealed similar results, where patients with IC or CIS had higher levels of hMAM protein (p<0.01 and p<0.01, respectively), while none of the negative controls expressed hMAM. Further analyses showed a strong correlation between hMAM protein/mRNA expression and clinicopathological factors, such as histological grade, clinical stage, and lymph node status, in patients with IC.

CONCLUSION

The hMAM mRNA and protein expression profiles validate the potential of hMAM as a specific marker for breast cancer diagnosis and target treatment delivery.

Safety and preliminary evidence of biologic efficacy of a mammaglobin-a DNA vaccine in patients with stable metastatic breast cancer

PURPOSE

Mammaglobin-A (MAM-A) is overexpressed in 40% to 80% of primary breast cancers. We initiated a phase I clinical trial of a MAM-A DNA vaccine to evaluate its safety and biologic efficacy.

EXPERIMENTAL DESIGN

Patients with breast cancer with stable metastatic disease were eligible for enrollment. Safety was monitored with clinical and laboratory assessments. The CD8 T-cell response was measured by ELISPOT, flow cytometry, and cytotoxicity assays. Progression-free survival (PFS) was described using the Kaplan-Meier product limit estimator.

RESULTS

Fourteen subjects have been treated with the MAM-A DNA vaccine and no significant adverse events have been observed. Eight of 14 subjects were HLA-A2(+), and the CD8 T-cell response to vaccination was studied in detail. Flow cytometry demonstrated a significant increase in the frequency of MAM-A-specific CD8 T cells after vaccination (0.9% ± 0.5% vs. 3.8% ± 1.2%; P < 0.001), and ELISPOT analysis demonstrated an increase in the number of MAM-A-specific IFNγ-secreting T cells (41 ± 32 vs. 215 ± 67 spm; P < 0.001). Although this study was not powered to evaluate progression-free survival (PFS), preliminary evidence suggests that subjects treated with the MAM-A DNA vaccine had improved PFS compared with subjects who met all eligibility criteria, were enrolled in the trial, but were not vaccinated because of HLA phenotype.

CONCLUSION

The MAM-A DNA vaccine is safe, capable of eliciting MAM-A-specific CD8 T-cell responses, and preliminary evidence suggests improved PFS. Additional studies are required to define the potential of the MAM-A DNA vaccine for breast cancer prevention and/or therapy.

Detection of circulating tumor cells in breast cancer patients using multiplex reverse transcription-polymerase chain reaction and specific primers for MGB, PTHRP and KRT19 correlation with clinicopathological features

AIM

The aim of this study was to correlate the clinicopathological features of breast cancer patients with the positive detection of parathyroid hormone-related protein (PTHRP), cytokeratin protein 19 (KRT19) and mammaglobin (MGB) using a multiplex reverse transcription polymerase chain reaction (RT-PCR) assay developed to detect circulating tumor cells (CTCs) in peripheral blood of patients with breast cancer.

PATIENTS AND METHODS

Peripheral blood samples were collected from 54 breast cancer patients and 20 healthy blood donors. Subsequently, the samples were processed for RNA extraction and analyzed for the expression of PTHRP, KRT19 and MGB using specific primers and multiplex RT-PCR.

RESULTS

The positive detection rates in breast cancer patients for PTHRP, KRT19 and MGB were 68.5%, 63% and 22.2% and for healthy donors 10%, 0% and 10%, respectively. The statistical analysis revealed that PTHRP- and KRT19-positive detections correlated with the diagnosis of breast cancer while the combined positive detections of PTHRP-plus-KRT19 correlated with the presence of distant metastasis, especially with bone metastasis. Moreover, positive detections of KRT19 correlated with high proliferation rate of breast cancer tumors. MGB-positive detections did not add any diagnostic advantage in such analysis.

CONCLUSION

Multiplex-PCR based detection of CTCs using PTHRP and KRT19 primers can provide useful information for the disease.

Mammaglobin A: review and clinical utility

Mammaglobin A is a protein that belongs to the secretoglobin superfamily. It has highly specific expression in cells from most breast cancers and may be used to detect circulating or disseminated tumor cells. In addition, mammaglobin A is currently under inves tigation as a potential therapeutic target for immune therapies that target breast cancer. The present review will highlight our current understanding of mammaglobin A at the genetic and protein level and its potential clinical applications. Characteristics of breast cancer and methods used to isolate and detect circulating tumor cells will also be presented.

[Expression of secretoglobin family 2A member 2 in oral lichen planus lesions]

OBJECTIVE

To examine the expression of secretoglobin family 2A member 2 (SCGB2A2) (mammaglobin A, MGB1) in oral lichen planus (OLP) lesions.

METHODS

Sixteen OLP patients and 10 healthy controls were included in this study. The real time reverse transcription-PCR (RT-PCR), Western blotting and immunohistochemistry (IHC) were used to determine the mRNA and protein of SCGB2A2.

RESULTS

Compared with healthy controls (0.48 ± 0.09), the expression of SCGB2A2 protein in OLP lesions significantly increased (1.02 ± 0.11) (P < 0.05).However, the mRNA level of SCGB2A2 in lesions was significantly lower than that in controls (P < 0.05).

CONCLUSIONS

These results suggest that SCGB2A2 may be involved in pathogenesis of OLP.

Detection of tumor cell-specific mRNA in the peripheral blood of patients with breast cancer—evaluation of several markers with real-time reverse transcription-PCR

It is widely known that cells from epithelial tumors, e.g., breast cancer, detach from their primary tissue and enter blood circulation. We show that the presence of circulating tumor cells (CTCs) in samples of patients with primary and metastatic breast cancer can be detected with an array of selected tumor-marker-genes by reverse transcription real-time PCR. The focus of the presented work is on detecting differences in gene expression between healthy individuals and adjuvant and metastatic breast cancer patients, not an accurate quantification of these differences. Therefore, total RNA was isolated from blood samples of healthy donors and patients with primary or metastatic breast cancer after enrichment of mononuclear cells by density gradient centrifugation. After reverse transcription real-time PCR was carried out with a set of marker genes (BCSP, CK8, Her2, MGL, CK18, CK19). B2M and GAPDH were used as reference genes. Blood samples from patients with metastatic disease revealed increased cytokine gene levels in comparison to normal blood samples. Detection of a single gene was not sufficient to detect CTCs by reverse transcription real-time PCR. Markers used here were selected based on a recent study detecting cancer cells on different protein levels. The combination of such a marker array leads to higher and more specific discovery rates, predominantly in metastatic patients. Identification of CTCs by PCR methods may lead to better diagnosis and prognosis and could help to choose an adequate therapy.

Cytokeratin-19 and mammaglobin gene expression in circulating tumor cells from metastatic breast cancer patients enrolled in North Central Cancer Treatment Group trials, N0234/336/436/437

PURPOSE

To investigate the associations between baseline and posttreatment circulating tumor cell (CTC) gene expression and outcome of patients enrolled in four North Central Cancer Treatment Group metastatic breast cancer (MBC) trials in which specimens were shipped (at 4°C) from community-based sites to a reference laboratory (Mayo Clinic, Rochester, MN).

EXPERIMENTAL DESIGN

Blood was collected at treating sites from MBC patients before (baseline), during, and at the end of treatment with erlotinib + gemcitabine (N0234), sorafenib (N0336), irinotecan + cetuximab (N0436), or paclitaxel-poliglumex + capecitabine (N0437). CTCs from 10 mL of EDTA blood were enriched with CD45 depletion, 24 to 30 hours postblood collection. Reverse transcription/quantitative PCR was used to determine cytokeratin-19 (CK19) and mammaglobin (MGB1) mRNA levels in CTCs from up to 13 (N0234), 16 (N0336), 18 (N0436), and 39 (N0437) patients. The gene expressions were normalized to β(2)-microglobulin and calibrated to healthy blood using the 2(-ΔΔCq) algorithm; positivity was defined as 2 or more.

RESULTS

CK19+mRNA cells were detected in 56% to 75% and MGB1+mRNA cells in 23% to 38% of 86 patients at baseline. CK19+mRNA cells were detected in 30% to 67% and MGB1+mRNA cells in 14% to 64% of 110 postbaseline serial samples. The presence of baseline CK19+mRNA cells (P = 0.01) but not MGB1+mRNA cells (P = 0.14) was significantly associated with shorter overall survival. A decrease in MGB1+mRNA levels (baseline-week 8) seemed to be associated with clinical response (P = 0.05).

CONCLUSIONS

CTC gene expression analysis conducted by a reference laboratory is feasible when blood is collected from treating sites and processed 24 to 30 hours postcollection. The presence of baseline CK19+mRNA CTCs was associated with poor prognosis; a decrease in MGB1+mRNA CTCs may help predict response to therapy of MBC patients.