Profiling protein markers associated with the sensitivity to concurrent chemoradiotherapy in human cervical carcinoma

Intact glycopeptides identified by LC-MS/MS as biomarkers for response to chemotherapy of locally advanced cervical cancer

Objective

For locally advanced cervical cancer (LACC), patients who respond to chemotherapy have a potential survival advantage compared to nonresponsive patients. Thus, it is necessary to explore specific biological markers for the efficacy of chemotherapy, which is beneficial to personalized treatment.

Methods

In the present study, we performed a comprehensive screening of site-specific N-glycopeptides in serum glycoproteins to identify glycopeptide markers for predicting the efficacy of chemotherapy, which is beneficial to personalized treatment. In total, 20 serum samples before and after neoadjuvant chemotherapy (NACT) from 10 LACC patients (NACT response, n=6) and NACT nonresponse, n=4) cases) were analyzed using LC-MS/MS, and 20 sets of mass spectrometry (MS) data were collected using liquid chromatography coupled with high-energy collisional dissociation tandem MS (LC-HCD-MS/MS) for quantitative analysis on the novel software platform, Byos. We also identified differential glycopeptides before and after chemotherapy in chemo-sensitive and chemo-resistant patients.

Results

In the present study, a total of 148 glycoproteins, 496 glycosylation sites and 2279 complete glycopeptides were identified in serum samples of LACC patients. Before and after chemotherapy, there were 13 differentially expressed glycoproteins, 654 differentially expressed glycopeptides and 93 differentially expressed glycosites in the NACT responsive group, whereas there were 18 differentially expressed glycoproteins, 569 differentially expressed glycopeptides and 99 differentially expressed glycosites in the NACT nonresponsive group. After quantitative analysis, 6 of 570 glycopeptides were identified as biomarkers for predicting the sensitivity of neoadjuvant chemotherapy in LACC. The corresponding glycopeptides included MASP1, LUM, ATRN, CO8A, CO8B and CO6. The relative abundances of the six glycopeptides, including MASP1, LUM, ATRN, CO8A, CO8B and CO6, were significantly higher in the NACT-responsive group and were significantly decreased after chemotherapy. High levels of these six glycopeptides may indicate that chemotherapy is effective. Thus, these glycopeptides are expected to serve as biomarkers for predicting the efficacy of neoadjuvant chemotherapy in locally advanced cervical cancer.

Conclusion

The present study revealed that the N-glycopeptide of MASP1, LUM, ATRN, CO8A, CO8B and CO6 may be potential biomarkers for predicting the efficacy of chemotherapy for cervical cancer.

Identification of Galectin-7 as a crucial metastatic enhancer of squamous cell carcinoma associated with immunosuppression

Metastasis predicts poor prognosis in cancer patients. It has been recognized that specific tumor microenvironment defines cancer cell metastasis, whereas the underlying mechanisms remain elusive. Here we show that Galectin-7 is a crucial mediator of metastasis associated with immunosuppression. In a syngeneic mouse squamous cell carcinoma (SCC) model of NR-S1M cells, we isolated metastasized NR-S1M cells from lymph nodes in tumor-bearing mice and established metastatic NR-S1M cells in in vitro culture. RNA-seq analysis revealed that interferon gene signature was markedly downregulated in metastatic NR-S1M cells compared with parental cells, and in vivo NR-S1M tumors heterogeneously developed focal immunosuppressive areas featured by deficiency of anti-tumor immune cells. Spatial transcriptome analysis (Visium) for the NR-S1M tumors revealed that various pro-metastatic genes were significantly upregulated in immunosuppressive areas when compared to immunocompetent areas. Notably, Galectin-7 was identified as a novel metastasis-driving factor. Galectin-7 expression was induced during tumorigenesis particularly in the microenvironment of immunosuppression, and extracellularly released at later stage of tumor progression. Deletion of Galectin-7 in NR-S1M cells significantly suppressed lymph node and lung metastasis without affecting primary tumor growth. Therefore, Galectin-7 is a crucial mediator of tumor metastasis of SCC, which is educated in the immune-suppressed tumor areas, and may be a potential target of cancer immunotherapy.

Glycosylation in Cervical Cancer: New Insights and Clinical Implications

Cervical cancer has become the most frequent female malignancy and presents as a general health challenge in many countries undergoing economic development. Various human papillomaviruses (HPV) types have appeared as one of the most critically identifiable causes of widespread cervical cancers. Conventional cervical cytological inspection has limitations of variable sensitivity according to cervical cytology. Glycobiology has been fundamental in related exploration in various gynecologic and reproductive fields and has contributed to our understanding of cervical cancer. It is associated with altered expression of N-linked glycan as well as abnormal expression of terminal glycan structures. The analytical approaches available to determine serum and tissue glycosylation, as well as potential underlying molecular mechanisms involved in the cellular glycosylation alterations, are monitored. Moreover, cellular glycosylation influences various aspects of cervical cancer biology, ranging from cell surface expressions, cell-cell adhesion, cancer signaling, cancer diagnosis, and management. In general, discoveries in glycan profiling make it technically reproducible and affordable to perform serum glycoproteomic analyses and build on previous work exploring an expanded variety of glycosylation markers in the majority of cervical cancer patients.

Genomic landscape analyses in cervical carcinoma and consequences for treatment

Where we are on the road to 'tailor-made' precision medicine for drug-resistant cervical carcinoma? We explored studies about analyses of viral and human genomes, epigenomes and transcriptomes, DNA mutation analyses, their importance in detecting HPV sequences, mechanisms of drug resistance to established and targeted therapies with small molecule or therapeutic antibodies, to radiosensitivity and to chemoradiotherapy. The value of repurposing of old drugs initially approved for other disease indications and now considered for cervix cancer therapy is also discussed. The microbiome influences drug response and survival too. HPV genomic integration sites were less significant. Nomograms (Lee et al., 2013) even outperformed FIGO staging regarding prediction of five-year overall survival times. We conclude that there are still many loose threads to be followed up, before coherent conclusions for individualized therapy of drug-resistant cervical carcinoma can be drawn.

Roles of S100 family members in drug resistance in tumors: Status and prospects

Chemotherapy and targeted therapy can significantly improve survival rates in cancer, but multiple drug resistance (MDR) limits the efficacy of these approaches. Understanding the molecular mechanisms underlying MDR is crucial for improving drug efficacy and clinical outcomes of patients with cancer. S100 proteins belong to a family of calcium-binding proteins and have various functions in tumor development. Increasing evidence demonstrates that the dysregulation of various S100 proteins contributes to the development of drug resistance in tumors, providing a basis for the development of predictive and prognostic biomarkers in cancer. Therefore, a combination of biological inhibitors or sensitizers of dysregulated S100 proteins could enhance therapeutic responses. In this review, we provide a detailed overview of the mechanisms by which S100 family members influence resistance of tumors to cancer treatment, with a focus on the development of effective strategies for overcoming MDR.

The Role of Galectins in Tumor Progression, Treatment and Prognosis of Gynecological Cancers

Galectins are the member of soluble proteins that bind with β-galactoside containing glycans. These proteins have been considered to be associated in various important events such as different types of cancers. It has been found that galectins could contribute to neoplastic transformation or regulate cell growth, cell apoptosis, and immune cells, causing tumor invasion, progression, metastasis and angiogenesis. Somehow, galectins are also found to exert a protective effect on cancer in a tissue-dependent way. These glycans binding proteins have been shown to be involved in the regulation of different tumor suppressor genes and oncogenes with their possible roles in human cancers. Objective of the current review is to summarize the role of galectin-1, -3 -7, and -9 in tumorigenesis of gynecological cancers. Galectin protein may be a potential therapeutic target in gynecological malignancies due to reported radio- and chemo- sensitivities, immunotherapeutic, anti-angiogenic and anti-proliferative activities. This review considers the evidence for the future research that how galectins may be important in the progression and treatment of gynecological cancers along with its potent use as a novel prognostic marker.

S100A9 regulates cisplatin chemosensitivity of squamous cervical cancer cells and related mechanism

Objective

Our previous research has shown that the expression of S100 calcium-binding protein A9 (S100A9) in tumor cells was associated with neoadjuvant chemotherapy sensitivity in cervical squamous cell carcinoma. In the present study, we altered the expression of S100A9 through infecting lentivirus, investigated its effect on the chemosensitivity to cisplatin of cervical cancer cells and then made a primary exploration of the involved mechanism.

Materials and methods

Lentivirus was employed to upregulate and downregulate S100A9 expression in SiHa cells. The protein expression level of apoptotic-related proteins Bcl-2 and Bax, drug resistance-related proteins multiple drug resistance protein 1 (MRP1), P glycoprotein (P-gp), glutathione-S-transferase-π (GST-π), lung resistance-related protein (LRP), and FOXO1 signaling pathway related proteins was detected by Western blot. The CCK-8 assay was used to examine chemosensitivity to cisplatin, and the proportion of apoptosis cells was analyzed by the flow cytometry.

Results

S100A9 overexpression could obviously increase the IC50 value of SiHa cells to cisplatin and decrease the apoptosis rate induced by cisplatin. Downregulation of S100A9 led to the opposite results. In S100A9 overexpression SiHa cells, the expression level of Bcl-2, LRP, GST-π, p-AKT, p-ERK, p-FOXO1, and Nanog was significantly increased, while FOXO1 expression was decreased. The opposite results were observed in S100A9 knockdown SiHa cells.

Conclusion

Downregulation of S100A9 could significantly increase apoptosis rate, resulting in enhancing sensitivity of SiHa cells to cisplatin, which may be related to Bcl-2, GST-π, and LRP protein and by altering the AKT/ERK-FOXO1-Nanog signaling pathway.

Antitumor effects of calgranulin B internalized in human colon cancer cells

Calgranulin B is a small, calcium-binding protein expressed in neutrophils that is secreted into the tumor microenvironment in cancer cases. We previously showed that calgranulin B levels are increased in the stools of colorectal cancer patients. In patient tumor tissues, calgranulin B protein levels correlated with the presence of stromal inflammatory cells surrounding tumor cells, and calgranulin B promoter methylation was observed in both paired human tissues and colon cancer cell lines. Cell lines did not express calgranulin B, but in vitro studies showed that colon cancer cells internalized extracellular calgranulin B, while other types of cancer cells did not. Calgranulin B internalization led to reduced cell proliferation and increased apoptotic cell death. AKT and ERK signals were also increased after calgranulin B treatment, as were p53, β-catenin, E-cadherin and cleaved caspase-3 levels. Additionally, a human protein microarray identified aurora A kinase as a calgranulin B binding partner, and binding inhibited aurora A kinase activity in a dose-dependent manner. Our findings demonstrate the antitumor effects of calgranulin B in the inflammatory microenvironment and suggest that calgranulin B could be potentially efficacious in the treatment of colon cancer.

Evaluation of short- and long-term efficacy of chemoradiotherapy for advanced cervical cancer using HSP70 protein combined with multimodal MRI

This study aims to evaluate the efficacy of chemoradiotherapy for advanced cervical cancer using heat shock protein 70 (HSP70) combined with multimodal MRI. The protein expressions of HSP70 in biopsy specimens obtained from 101 patients with cervical cancer were detected by immunohistochemistry. Plain MRI scan, DWI, DCE-MR, and MRS were performed before and after a period of 6 months of chemoradiotherapy. All patients were assigned into the complete response (CR) and partial response (PR) groups. HSP70 protein expression, tumor diameter, and tumor volume were lower in the CR group than in the PR group. The rate of tumor shrinkage, relative positive enhancement integral (rPEI), relative maximum slope of decrease (rMSD), relative signal enhancement ratio at 60 s (rSER₆₀ ) and maximum SER (rSER_max ), mean apparent diffusion coefficient (ADC_mean ) and minimum ADC value (ADC_min ) values in the CR group were higher than those in the PR group. Tumor diameter and volume, rSER₁₅ and rSER₃₀ were reduced after chemoradiotherapy, while rMSD, rSER_max , time to peak (TTP), ADC_mean and ADC_min were higher after the treatment. The receiver operating characteristic (ROC) curves indicated that HSP70 expression, tumor diameter, rPEI, ADC_mean and Cho peak showed the better chemoradiotherapy efficacy. Our data demonstrates that HSP70 protein combined with multimodal MRI may accurately evaluate the chemoradiotherapy efficacy of patients with advanced cervical cancer. The recurrence of cervical cancer significantly decreased in patients with negative expression of HSP70 and HSP70 protein detection provides potential therapy for the prevention, diagnosis, and prognosis of cervical cancer.

Proteomics approaches in cervical cancer: focus on the discovery of biomarkers for diagnosis and drug treatment monitoring

INTRODUCTION

The HPV virus accounts for the majority of cervical cancer cases. Although a diagnostic tool (Pap Test) is widely available, cervical cancer incidence still remains high worldwide, and especially in developing countries, attributed to a large extent to suboptimal sensitivities of the Pap test and unavailability of the test in developing countries.

AREAS COVERED

Proteomics approaches have been used in order to understand the HPV virus correlation to cervical cancer pathology, as well as to discover putative biomarkers for early cervical cancer diagnosis and drug mode of action. Expert commentary: The present review summarizes the latest in vitro and in vivo proteomic studies for the discovery of putative cervical cancer biomarkers and the evaluation of available drugs and treatments.

Role of galectins in lung cancer

Lung cancer is the leading cause of cancer-associated mortality worldwide and is also associated with a poor prognosis. As in numerous other types of cancer, galectins have been demonstrated to be involved in the progression of lung cancer. Galectins belong to a superfamily of lectins, which are carbohydrate-binding proteins. There are at least 15 members in the galectin family, however, only galectin-1, −2, −3, −4, −7, −8, −9, −10, −12, and −13 are found in humans. Galectins are able to mediate interactions between cells, including homotypic and heterotypic interactions; they also facilitate the bindings between cells and extracellular matrix components. These cell-cell and cell-matrix interactions, as well as the galectin signaling on the cell surface, are able to modulate signaling pathways and thereby influence cellular functions and behaviors. Galectin-1, −3, −4, −7, −8 and −9 are associated with lung cancer. These galectins are associated with tumor invasion, migration, metastasis and progression, and may serve important roles in the tumor microenvironment of lung cancer. The majority of galectins are associated with the progression of lung cancer, with the exception of galectin-9, which is associated with enhanced anticancer immunity. Therefore, galectins may be potential targets for developing novel lung cancer therapies.

Galectin-7 is epigenetically-regulated tumor suppressor in gastric cancer

Gastric cancer is the second leading cause of cancer death and remains a major clinical challenge due to poor prognosis and limited treatment options. Therefore, the basic mechanisms underlying gastric tumorigenesis deserve investigation. Although regulation of the galactoside-binding lectin galectin-7 in cancer has been studied, its role in tumor formation and progression remains controversial. In this study, we investigated galectin-7 expression and its role in gastric cancer. Immunohistochemical staining using a tissue microarray of gastric cancer patients revealed significantly low expression levels of galectin-7 in malignant tissues compared with matched normal tissues, and decreased expression of galectin-7 in malignant tissues was associated with advanced TMN stage disease (p =0.034). Importantly, low expression of galectin-7 in normal tissues was associated with a poor survival rate (p =0.0561). Over-expression of galectin-7 in AGS gastric adenocarcinoma cells suppressed cell proliferation, migration, and invasion, whereas ablation of galectin-7 in KATO III gastric carcinoma cells reversed these properties. AGS cells that overexpressed galectin-7 could not form gastric tumors in xenografted mice. More than 70% hypermethylation was observed in 7 of 9 gastric cancer cell lines tested and 5-aza-cytidine treatment lowered galectin-7 expression by reducing methylation in 24 cancer cell lines from five different organ origins. We analyzed CpG islands in the galectin-7 genomic region and detected hypermethylation at +1566bp of exon 2, the predicted p53 binding region. DNA hypermethylation of this region was also detected in gastric cancer tissues from 20 patients. Taken together, our data indicate that galectin-7 has a tumor suppressive function, and that the gene is epigenetically modified by DNA methylation and significantly down-regulated in gastric cancer. Further study of galectin-7 regulation may lead to improved gastric cancer diagnosis and therapy.

Expression and functions of galectin-7 in human and murine melanomas

The identification of galectin-7 as a p53-induced gene and its ability to induce apoptosis in many cell types support the hypothesis that galectin-7 has strong antitumor activity. This has been well documented in colon cancer. However, in some cases, such as breast cancer and lymphoma, its high expression level correlates with aggressive subtypes of cancer, suggesting that galectin-7 may have a dual role in cancer progression. In fact, in breast cancer, overexpression of galectin-7 alone is sufficient to promote metastasis to the bone and lung. In the present work, we investigated the expression and function of galectin-7 in melanoma. An analysis of datasets obtained from whole-genome profiling of human melanoma tissues revealed that galectin-7 mRNA was detected in more than 90% of biopsies of patients with nevi while its expression was more rarely found in biopsies collected from patients with malignant melanoma. This frequency, however, was likely due to the presence of normal epidermis tissues in biopsies, as shown our studies at the protein level by immunohistochemical analysis. Using the experimental melanoma B16F1 cell line, we found that melanoma cells can express galectin-7 at the primary tumor site and in lung metastasis. Moreover, we found that overexpression of galectin-7 increased the resistance of melanoma cells to apoptosis while inducing de novo egr-1 expression. Overexpression of galectin-7, however, was insufficient to modulate the growth of tumors induced by the subcutaneous injection of B16F1 cells. It also failed to modulate the dissemination of B16F1 cells to the lung.

Identification of differentially expressed proteins in chemotherapy-sensitive and chemotherapy-resistant diffuse large B cell lymphoma by proteomic methods

In the present study, we employed proteomic methods to identify and quantitate differentially expressed proteins between diffuse large B cell lymphoma (DLBCL) tissues with low and high sensitivity to combinatorial cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy and explored protein networks associated with DLBCL chemoresistance to CHOP. For proteomics analysis, DLBCL tissues were collected from 14 untreated patients. Two-dimensional gel electrophoresis combined with mass spectrometry (MS) were employed to identify and quantitate differentially expressed proteins in DLBCL tissues with low or high sensitivity to CHOP chemotherapy in vitro. Nineteen proteins showing an over twofold change in the MS/MS ions score between the low sensitivity and the high sensitivity groups were identified as differentially expressed proteins and confirmed by Western blot analyses. Immunohistochemical analyses were performed in DLBCL tissue samples from 98 patients who had received four cycles of CHOP chemotherapy, which showed that expressions of the identified CHOP sensitivity biomarkers were significantly associated with therapeutic outcomes of DLBCL, suggesting that the biomarkers could be used to predict DLBCL patient outcomes. This study provides important insights into understanding the molecular basis for development of multi-drug chemoresistance in DLBCL, which may serve as a basis for identification of novel therapeutic targets and biomarkers involved in the emergence and maintenance of DLBCL resistance to CHOP.

Comparative proteomic study for profiling differentially expressed proteins between Chinese left- and right-sided colon cancers

The aim of the present study is to profile differentially expressed protein markers between left-sided colon cancer (LSCC) and right-sided colon cancer (RSCC). Fresh tumor tissue samples from LSCC (n = 7) and RSCC (n = 7) groups were analyzed by two-dimensional electrophoresis coupled with MALDI-TOF-MS, followed by Western blotting. In 50 paraffin embedded samples from each group, levels of four differentially expressed proteins (identified by proteomics analysis) were measured by tissue microarray with immunohistochemistry staining to compare the different protein markers between LSCC and RSCC. Sixteen proteins were found to be differentially expressed between LSCC and RSCC. Ten proteins including HSP-60 and PDIA1 were identified to be highly expressed in LSCC (P < 0.01 or P < 0.05), while the expression of six proteins including EEF1D and HSP-27 were higher in RSCC (P < 0.01 or P < 0.05). Virtually all of the indentified proteins were involved in cellular energy metabolism, protein folding/unfolding, and/or oxidative stress. Human colon tumors at various locations have different proteomic biomarkers. Differentially expressed proteins associated with energy metabolism, protein folding/unfolding and oxidative stress contribute to different tumorigenesis, tumor progression, and prognosis between left- and right-sided colon cancer.

Review of S100A9 biology and its role in cancer

S100A9 is a calcium binding protein with multiple ligands and post-translation modifications that is involved in inflammatory events and the initial development of the cancer cell through to the development of metastatic disease. This review has a threefold purpose: 1) describe the S100A9 structural elements important for its biological activity, 2) describe the S100A9 biology in the context of the immune system, and 3) illustrate the role of S100A9 in the development of malignancy via interactions with the immune system and other cellular processes.

Galectin 1 expression is associated with tumor invasion and metastasis in stage IB to IIA cervical cancer

Galectin 1 is a 14-kd laminin-binding lectin involved in important biologic mechanisms of tumors, including neoplastic transformation, cell survival, angiogenesis, cell proliferation, and metastasis. In this study, we investigated the role of galectin 1 in cell survival and metastasis in cervical cancer. The expression of galectin 1 was determined in 73 formalin-fixed, paraffin-embedded cervical cancer tissues using an immunohistochemical method and compared with clinicopathologic risk factors for recurrence after surgery. To evaluate the role of galectin 1 in cell proliferation and invasion, we performed proliferation and invasion assays with galectin 1 small interfering RNA (siRNA) using cervical cancer cell lines, including HeLa and SiHa cells. Immunohistochemical analysis revealed that galectin 1 expression was found in most peritumoral stroma samples (72/73; 98.6%). Galectin 1 expression was significantly correlated with the depth of invasion in the cervix (P=.015) and lymph node metastasis (P=.045) on univariate analysis. When progression-free survival of all of the patients studied was analyzed based upon galectin 1 expression, galectin 1 expression was not correlated with progression-free survival (P=.32). Down-regulation of galectin 1 using small interfering RNA resulted in the inhibition of cell growth and proliferation of HeLa and SiHa cells. Moreover, the ability of cells to invade was significantly reduced by galectin 1 small interfering RNA. Our results revealed that high galectin 1 expression in peritumoral stroma was significantly correlated with depth of invasion in cervical lesions and lymph node metastasis of cervical cancer and that galectin 1 may be functionally involved in cell proliferation and invasion.

Roles of galectin-7 and S100A9 in cervical squamous carcinoma: Clinicopathological and in vitro evidence

In our study, we for the first time assessed the association of galectin-7 and S100A9 with clinicopathological variables and survival outcomes in cervical squamous carcinoma patients and explored the underlying molecular mechanisms in cervical squamous carcinoma cell lines. Immunohistochemical analysis of 243 patient samples showed that the positive staining rate for galectin-7 and S100A9 gradually decreased from normal cervical tissue to intraepithelial neoplasia and to cervical squamous carcinoma. Both galectin-7 and S100A9 showed significant negative association with lymph node metastasis and staging of cervical squamous carcinoma. Cervical squamous carcinoma patients with negative staining of galectin-7 or S100A9 showed significantly lower 5-year overall survival rate than those with positive staining. Multivariate analysis with the Cox's proportional hazards model indicated that both galectin-7 and S100A9 had significant protective effect on cervical squamous carcinoma patients. Subsequent in vitro study in SiHa and C-33A human cervical squamous carcinoma cell lines revealed that knocking down galectin-7 or S100A9 enhanced tumor cell invasion and tumor cell viability against paclitaxel-induced apoptotic stress, likely through increasing the matrix metalloproteinase-9 expression and activating the phosphatidylinositol 3-kinase/Akt signaling pathway, respectively. Knocking down both galectin-7 and S100A9 produced a synergistic effect, with galectin-7 displaying more significant and consistent protective effects than S100A9 on cervical squamous carcinoma cells. In summary, our study for the first time provides clinicopathological and in vitro evidence showing that both galectin-7 and S100A9 play important protective roles in cervical squamous carcinoma, which provides fresh insights into the biology of cervical squamous carcinoma.

Immunohistochemical expression of Annexin A2 and S100A proteins in patients with bulky stage IB-IIA cervical cancer treated with neoadjuvant chemotherapy

OBJECTIVE

Abnormal expression of Annexin A2 and S100A proteins has been reported to induce sensitivity/resistance to chemotherapy in a variety of cancers. The aim of this study was to evaluate the significance of Annexin A2 and S100A protein expression to predict response to neoadjuvant chemotherapy and prognostic significance of these protein expressions in bulky stage IB-IIA cervical cancer patients.

METHODS

Paired tumor samples (pre- and post-chemotherapy) were obtained from 68 patients who were treated with cisplatin-based neoadjuvant chemotherapy and radical hysterectomy at our hospital from 2006 to 2011. The expression of Annexin A2 and S100A proteins was analyzed by immunohistochemistry.

RESULTS

Thirty-six patients were identified as chemotherapy-response and 32 were non-response. (a). Protein expression in tumor cells: (1). Exposure of tumor cells to chemotherapy results in a change of Annexin A2 and S100A expression (P<0.05). (2). Annexin A2, S100A8 and S100A9 protein expression correlates with tumor response to chemotherapy (P<0.05). (b). Protein expression in stromal cells: (1). Expression of Annexin A2, S100A8 and S100A9 was increased, but S100A2 and S100A4 was decreased after exposure to chemotherapy (P<0.05). (2). Only S100A4 expression was associated with response to chemotherapy (P<0.05). Multivariate analysis revealed that tumor size (P=0.022), differentiation (P=0.000), Annexin A2 expression in stromal cells (P=0.009), and S100A8 expression in tumor cells (P=0.008) were independent prognostic factors for progression-free survival of cervical cancer patients.

CONCLUSIONS

Expression of some of the measured proteins in tumor and stromal cells correlates with chemotherapy exposure, response to therapy, and progression-free survival.

Proteomic approach reveals FKBP4 and S100A9 as potential prediction markers of therapeutic response to neoadjuvant chemotherapy in patients with breast cancer

Although doxorubicin (Doxo) and docetaxel (Docet) in combination are widely used in treatment regimens for a broad spectrum of breast cancer patients, a major obstacle has emerged in that some patients are intrinsically resistant to these chemotherapeutics. Our study aimed to discover potential prediction markers of drug resistance in needle-biopsied tissues of breast cancer patients prior to neoadjuvant chemotherapy. Tissues collected before chemotherapy were analyzed by mass spectrometry. A total of 2,331 proteins were identified and comparatively quantified between drug sensitive (DS) and drug resistant (DR) patient groups by spectral count. Of them, 298 proteins were differentially expressed by more than 1.5-fold. Some of the differentially expressed proteins (DEPs) were further confirmed by Western blotting. Bioinformatic analysis revealed that the DEPs were largely associated with drug metabolism, acute phase response signaling, and fatty acid elongation in mitochondria. Clinical validation of two selected proteins by immunohistochemistry found that FKBP4 and S100A9 might be putative prediction markers in discriminating the DR group from the DS group of breast cancer patients. The results demonstrate that a quantitative proteomics/bioinformatics approach is useful for discovering prediction markers of drug resistance, and possibly for the development of a new therapeutic strategy.

The role of tissue microarray in the era of target-based agents

Tissue microarray (TMA) technologies have been developed over the last years, mainly to identify biomarkers useful for the correct identification and characterization of tumors. Moreover, TMA has been implemented in retrospective studies in order to identify predictive biomarkers of response to a given therapy and/or to find potential new targets for biological therapy. We analyzed the fields of application of TMA technology and the design of TMA varying according to the objectives to be studied. In this article, the reader will learn how to design TMAs in order to cover the objectives of clinical trials based upon the use of target-based agents. The main limits and advantages of TMA and the results achieved in cancer diagnosis will be also described. Tissue microarray technology should be systematically applied to define critical markers, in retrospective studies and in the screening of most human tumors in order to find new possible molecular targets and to molecularly define the diagnosis of the neoplastic diseases. TMAs have substantially improved the field of translational studies, even in the design and follow-up of studies based upon the use of target-based agents in cancer therapy.