Bcl-2 and BLIMP-1 expression predict worse prognosis in gastric diffuse large B cell lymphoma (DLCBL) while other markers for nodal DLBCL are not useful

Brain endothelial cells promote breast cancer cell extravasation to the brain via EGFR-DOCK4-RAC1 signalling

The role of endothelial cells in promoting cancer cell extravasation to the brain during the interaction of cancer cells with the vasculature is not well characterised. We show that brain endothelial cells activate EGFR signalling in triple-negative breast cancer cells with propensity to metastasise to the brain. This activation is dependent on soluble factors secreted by brain endothelial cells, and occurs via the RAC1 GEF DOCK4, which is required for breast cancer cell extravasation to the brain in vivo. Knockdown of DOCK4 inhibits breast cancer cell entrance to the brain without affecting cancer cell survival or growth. Defective extravasation is associated with loss of elongated morphology preceding intercalation into brain endothelium. We also show that brain endothelial cells promote paracrine stimulation of mesenchymal-like morphology of breast cancer cells via DOCK4, DOCK9, RAC1 and CDC42. This stimulation is accompanied by EGFR activation necessary for brain metastatic breast cancer cell elongation which can be reversed by the EGFR inhibitor Afatinib. Our findings suggest that brain endothelial cells promote metastasis through activation of cell signalling that renders breast cancer cells competent for extravasation. This represents a paradigm of brain endothelial cells influencing the signalling and metastatic competency of breast cancer cells.

An open-label, pilot study of veliparib and lapatinib in patients with metastatic, triple-negative breast cancer

BACKGROUND

Poly (ADP-ribose)-polymerase inhibitors (PARPi) have been approved for cancer patients with germline BRCA1/2 (gBRCA1/2) mutations, and efforts to expand the utility of PARPi beyond BRCA1/2 are ongoing. In preclinical models of triple-negative breast cancer (TNBC) with intact DNA repair, we have previously shown an induced synthetic lethality with combined EGFR inhibition and PARPi. Here, we report the safety and clinical activity of lapatinib and veliparib in patients with metastatic TNBC.

METHODS

A first-in-human, pilot study of lapatinib and veliparib was conducted in metastatic TNBC (NCT02158507). The primary endpoint was safety and tolerability. Secondary endpoints were objective response rates and pharmacokinetic evaluation. Gene expression analysis of pre-treatment tumor biopsies was performed. Key eligibility included TNBC patients with measurable disease and prior anthracycline-based and taxane chemotherapy. Patients with gBRCA1/2 mutations were excluded.

RESULTS

Twenty patients were enrolled, of which 17 were evaluable for response. The median number of prior therapies in the metastatic setting was 1 (range 0-2). Fifty percent of patients were Caucasian, 45% African-American, and 5% Hispanic. Of evaluable patients, 4 demonstrated a partial response and 2 had stable disease. There were no dose-limiting toxicities. Most AEs were limited to grade 1 or 2 and no drug-drug interactions noted. Exploratory gene expression analysis suggested baseline DNA repair pathway score was lower and baseline immunogenicity was higher in the responders compared to non-responders.

CONCLUSIONS

Lapatinib plus veliparib therapy has a manageable safety profile and promising antitumor activity in advanced TNBC. Further investigation of dual therapy with EGFR inhibition and PARP inhibition is needed.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT02158507 . Registered on 12 September 2014.

Navitoclax enhances the effectiveness of EGFR-targeted antibody-drug conjugates in PDX models of EGFR-expressing triple-negative breast cancer

BACKGROUND

Targeted therapies for triple-negative breast cancer (TNBC) are limited; however, the epidermal growth factor receptor (EGFR) represents a potential target, as the majority of TNBC express EGFR. The purpose of these studies was to evaluate the effectiveness of two EGFR-targeted antibody-drug conjugates (ADC: ABT-414; ABBV-321) in combination with navitoclax, an antagonist of the anti-apoptotic BCL-2 and BCL-XL proteins, in order to assess the translational relevance of these combinations for TNBC.

METHODS

The pre-clinical efficacy of combined treatments was evaluated in multiple patient-derived xenograft (PDX) models of TNBC. Microscopy-based dynamic BH3 profiling (DBP) was used to assess mitochondrial apoptotic signaling induced by navitoclax and/or ADC treatments, and the expression of EGFR and BCL-2/XL was analyzed in 46 triple-negative patient tumors.

RESULTS

Treatment with navitoclax plus ABT-414 caused a significant reduction in tumor growth in five of seven PDXs and significant tumor regression in the highest EGFR-expressing PDX. Navitoclax plus ABBV-321, an EGFR-targeted ADC that displays more effective wild-type EGFR-targeting, elicited more significant tumor growth inhibition and regressions in the two highest EGFR-expressing models evaluated. The level of mitochondrial apoptotic signaling induced by single or combined drug treatments, as measured by DBP, correlated with the treatment responses observed in vivo. Lastly, the majority of triple-negative patient tumors were found to express EGFR and co-express BCL-XL and/or BCL-2.

CONCLUSIONS

The dramatic tumor regressions achieved using combined agents in pre-clinical TNBC models underscore the abilities of BCL-2/XL antagonists to enhance the effectiveness of EGFR-targeted ADCs and highlight the clinical potential for usage of such targeted ADCs to alleviate toxicities associated with combinations of BCL-2/XL inhibitors and systemic chemotherapies.

Prognostic impact of PD-L1 expression in primary gastric and intestinal diffuse large B-cell lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease and the most common gastrointestinal lymphoma. The prognostic/predictive indicators among patients with gastric and intestinal DLBCL (giDLBCL) are controversial beyond their anatomical sites. We compared giDLBCL cases and investigated the clinical utility of newly emerging indicators with an emphasis on programmed cell death ligand 1 (PD-L1) expression.

METHODS

This retrospective study included 174 patients with primary gastric (n = 129) or intestinal (n = 45) DLBCL treated with rituximab-containing chemotherapy between 1995 and 2018.

RESULTS

Compared with gastric DLBCL (gDLBCL) cases, patients with intestinal DLBCL (iDLBCL) had a significantly higher rate of advanced Lugano stage (71% vs 37%, P < 0.001), perforation (13% vs. 0.8%, P = 0.001), PD-L1 expression on microenvironment immune cells (miPD-L1, 70% vs 46%, P = 0.008), CD10 positivity (47% vs 28%, P = 0.027), and CD5 positivity (9% vs 1.6%, P = 0.040). The iDLBCL patients showed significantly worse progression-free survival (PFS) and overall survival (OS) than gDLBCL cases (P = 0.0338 and P = 0.0077, respectively). PD-L1 expression on tumor cells was detected in only 3 (2%) of 174 cases with early relapse and/or an aggressive clinical course; whereas, miPD-L1-positive cases had significantly better OS than the miPD-L1-negative gDLBCL and iDLBCL cases (P = 0.0281 and P = 0.0061, respectively). Multivariate analysis revealed that miPD-L1 negativity (P = 0.030) was an independent adverse prognostic factor for OS in giDLBCL.

CONCLUSIONS

The anatomical site of disease did not influence outcome in giDLBCL cases treated with rituximab-containing chemotherapy; while, miPD-L1 expression had a favorable impact on the outcome.

Riluzole synergizes with paclitaxel to inhibit cell growth and induce apoptosis in triple-negative breast cancer

PURPOSE

One in eight women will develop breast cancer, 15-20% of whom will have triple-negative breast cancer (TNBC), an aggressive breast cancer with no current targeted therapy. We have demonstrated that riluzole, an FDA-approved drug for treating amyotrophic lateral sclerosis, inhibits growth of TNBC. In this study, we explore potential synergism between riluzole and paclitaxel, a chemotherapeutic agent commonly used to treat TNBC, in regulating TNBC proliferation, cell cycle arrest, and apoptosis.

METHODS

TNBC cells were treated with paclitaxel and/or riluzole and synergistic effects on cell proliferation were quantified via MTT assay and CompuSyn analysis. Apoptosis was observed morphologically and by measuring cleaved PARP/caspase three products. Microarray analysis was performed using MDA-MB-231 cells to examine cell cycle genes regulated by riluzole and any enhanced effects on paclitaxel-mediated cell cycle arrest, determined by FACS analysis. These results were confirmed in vivo using a MDA-MB-231 xenograft model.

RESULTS

Strong enhanced or synergistic effects of riluzole on paclitaxel regulation of cell cycle progression and apoptosis was demonstrated in all TNBC cells tested as well as in the xenograft model. The MDA-MB-231, SUM149, and SUM229 cells, which are resistant to paclitaxel treatment, demonstrated the strongest synergistic or enhanced effect. Key protein kinases were shown to be upregulated in this study by riluzole as well as downstream cell cycle genes regulated by these kinases.

CONCLUSIONS

All TNBC cells tested responded synergistically to riluzole and paclitaxel strongly suggesting the usefulness of this combinatorial treatment strategy in TNBC, especially for patients whose tumors are relatively resistant to paclitaxel.

Mutations of the Epidermal Growth Factor Receptor Gene in Triple-Negative Breast Cancer

Purpose

Epidermal growth factor receptor (EGFR) is considered a potential therapeutic target for anti-EGFR therapy in triple-negative breast cancer (TNBC). However, the frequency of EGFR gene mutation in TNBC is low and varies with ethnicity. This study aimed to investigate the incidence of EGFR gene mutation in TNBC.

Methods

EGFR protein expression was evaluated by immunohistochemistry in tissue microarrays of 493 TNBC cases using four different primary antibodies, which included mutation-specific antibodies. For cases with an immunoreactivity level ≥1+, we performed pyrosequencing analysis for EGFR gene mutation. A case was considered mutation-positive when its mutation frequency minus its limit of detection (LOD) was >10%. Cases with mutation frequency higher than LOD were assessed for EGFR gene mutation status using the Cobas assay and by peptide nucleic acid-mediated polymerase chain reaction (PNA-clamping).

Results

Among 493 TNBCs, 148 (30.0%) exhibited staining ≥1+ for EGFR, including 78 with 1+, 49 with 2+, and 21 with 3+. Positive EGFR expression (≥2+) was significantly associated with lymphovascular invasion (p=0.010), but not with overall survival (p=0.444) or disease-free survival (p=0.388). None of the 493 TNBCs harbored an EGFR gene mutation. Among 148 cases with an EGFR staining result ≥1+, five (3.4%) showed mutation frequencies (4.4%–10.9%) higher than LOD (2.6%–4.3%) in exons 19 (L747_P753>Q) or 21 (L858R and L861Q) as determined by pyrosequencing. However, Cobas and PNA-clamping failed to detect the presence of EGFR gene mutation in these five cases.

Conclusion

No activating mutation of EGFR gene of clinical significance was observed in 148 TNBC cases using three commercially available methods. Thus, EGFR gene mutation appears to be an extremely rare event in patients with TNBC.

Blimp-1 impairs T cell function via upregulation of TIGIT and PD-1 in patients with acute myeloid leukemia

Background

T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT) and programmed cell death protein 1 (PD-1) are important inhibitory receptors that associate with T cell exhaustion in acute myeloid leukemia (AML). In this study, we aimed to determine the underlying transcriptional mechanisms regulating these inhibitory pathways. Specifically, we investigated the role of transcription factor B lymphocyte-induced maturation protein 1 (Blimp-1) in T cell response and transcriptional regulation of TIGIT and PD-1 in AML.

Methods

Peripheral blood samples collected from patients with AML were used in this study. Blimp-1 expression was examined by flow cytometry. The correlation of Blimp-1 expression to clinical characteristics of AML patients was analyzed. Phenotypic and functional studies of Blimp-1-expressing T cells were performed using flow cytometry-based assays. Luciferase reporter assays and ChIP assays were applied to assess direct binding and transcription activity of Blimp-1. Using siRNA to silence Blimp-1, we further elucidated the regulatory role of Blimp-1 in the TIGIT and PD-1 expression and T cell immune response.

Results

Blimp-1 expression is elevated in T cells from AML patients. Consistent with exhaustion, Blimp-1⁺ T cells upregulate multiple inhibitory receptors including PD-1 and TIGIT. In addition, they are functionally impaired manifested by low cytokine production and decreased cytotoxicity capacity. Importantly, the functional defect is reversed by inhibition of Blimp-1 via siRNA knockdown. Furthermore, Blimp-1 binds to the promoters of PD-1 and TIGIT and positively regulates their expression.

Conclusions

Our study demonstrates an important inhibitory effect of Blimp-1 on T cell response in AML; thus, targeting Blimp-1 and its regulated molecules to improve the immune response may provide effective leukemia therapeutics.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-017-0486-z) contains supplementary material, which is available to authorized users.

Recent Advances in Aggressive Large B-cell Lymphomas: A Comprehensive Review

Diffuse large B-cell lymphoma (DLBCL) is an aggressive disease with considerable heterogeneity reflected in the 2008 World Health Organization classification. In recent years, genome-wide assessment of genetic and epigenetic alterations has shed light upon distinct molecular subsets linked to dysregulation of specific genes or pathways. Besides fostering our knowledge regarding the molecular complexity of DLBCL types, these studies have unraveled previously unappreciated genetic lesions, which may be exploited for prognostic and therapeutic purposes. Following the last World Health Organization classification, we have witnessed the emergence of new variants of specific DLBCL entities, such as CD30 DLBCL, human immunodeficiency virus-related and age-related variants of plasmablastic lymphoma, and EBV DLBCL arising in young patients. In this review, we will present an update on the clinical, pathologic, and molecular features of DLBCL incorporating recently gained information with respect to their pathobiology and prognosis. We will emphasize the distinctive features of newly described or emerging variants and highlight advances in our understanding of entities presenting a diagnostic challenge, such as T-cell/histiocyte-rich large B-cell lmphoma and unclassifiable large B-cell lymphomas. Furthermore, we will discuss recent advances in the genomic characterization of DLBCL, as they may relate to prognostication and tailored therapeutic intervention. The information presented in this review derives from English language publications appearing in PubMed throughout December 2015. For a complete outline of this paper, please visit: http://links.lww.com/PAP/A12.

High EGFR protein expression and exon 9 PIK3CA mutations are independent prognostic factors in triple negative breast cancers

BACKGROUND

Triple negative breast cancers (TNBC) are a more aggressive subset of breast cancer. A better understanding of its biology could allow the rational development of targeted therapies.

METHODS

We extensively analyzed the EGFR/PI3K/PTEN axis in a large, homogeneous population of TNBC to help defining the putative role of anti-EGFR and -PI3K targeted therapies in this setting. EGFR gene amplification, EGFR protein expression, PIK3CA and PTEN gene alterations (two members of EGFR downstream pathways) and their clinicopathological and prognostic implications were analyzed in 204 TNBC samples from European patients.

RESULTS

EGFR amplification was detected in 18 of the 204 TNBC specimens (8.9 %) and was significantly associated with higher EGFR protein levels. Fourteen PIK3CA mutations were identified in exon 9 (6.7 %), and 17 in exon 20 (8.3 %). PIK3CA mutations, especially in exon 9, were significantly associated with grade I-II tumors. PTEN deletions were detected in 43 samples (21.50 %) and were significantly associated with grade III tumors (p < 0.001). Univariate analysis showed a significant association between relapse-free survival (RFS), T and N stage and exon 9 PIK3CA mutations. Overall survival was significantly associated with T stage, N stage and adjuvant chemotherapy, which was administered to 70.3 % of patients. In multivariate analyses, T stage, N stage, presence of exon 9 PIK3CA mutations and high EGFR protein level were independent poor prognostic factors for RFS, while adjuvant chemotherapy was associated with a better outcome.

CONCLUSIONS

High EGFR protein expression and exon 9 PIK3CA activating mutations are independent prognostic factors in TNBC. The efficacy of anti-PI3K targeted therapies needs to be evaluated in this setting.

P38 MAPK expression and activation predicts failure of response to CHOP in patients with Diffuse Large B-Cell Lymphoma

BACKGROUND

The p38 MAPK is constitutively activated in B-NHL cell lines and regulates chemoresistance. Accordingly, we hypothesized that activated p38 MAPK may be associated with the in vivo unresponsiveness to chemotherapy in B-NHL patients.

METHODS

Tissue microarrays generated from eighty untreated patients with Diffused Large B Cell Lymphoma (DLBCL) were examined by immunohistochemistry for the expression of p38 and phospho p38 (p-p38) MAPK. In addition, both Bcl-2 and NF-κB expressions were determined. Kaplan Meier analysis was assessed.

RESULTS

Tumor tissues expressed p38 MAPK (82 %) and p-p38 MAPK (30 %). Both p38 and p-p38 MAPK expressions correlated with the high score performance status. A significant correlation was found between the expression p-p38 and poor response to CHOP. The five year median follow-up FFS was 81 % for p38(-) and 34 % for p38(+) and for OS was 83 % for p38(-) and 47 % for p38(+). The p-p38(+) tissues expressed Bcl-2 and 90 % of p-p38(-) where Bcl-2(-). The coexpression of p-p38 and Bcl-2 correlated with pool EFS and OS. There was no correlation between the expression of p-p38 and the expression of NF-κB.

CONCLUSION

The findings revealed, for the first time, that a subset of patients with DLBCL and whose tumors expressed high p-p38 MAPK responded poorly to CHOP therapy and had poor EFS and OS. The expression of p38, p-p38, Bcl2 and the ABC subtype are significant risk factors both p38 and p-p38 expressions remain independent prognostic factors.

Prognostic and predictive values of EGFR overexpression and EGFR copy number alteration in HER2-positive breast cancer

Background:

Epidermal growth factor receptor (EGFR) is overexpressed in a subset of human epidermal growth factor receptor 2 (HER2)-positive breast cancers, and coexpression of HER2 and EGFR has been reported to be associated with poor clinical outcome. Moreover, interaction between HER2 and EGFR has been suggested to be a possible basis for trastuzumab resistance.

Methods:

We analysed the clinical significance of EGFR overexpression and EGFR gene copy number alterations in 242 HER2-positive primary breast cancers. In addition, we examined the correlations between EGFR overexpression, trastuzumab response and clinical outcome in 447 primary, and 112 metastatic HER2-positive breast cancer patients treated by trastuzumab.

Results:

Of the 242 primary cases, the level of EGFR overexpression was 2+ in 12.7% and 3+ in 11.8%. High EGFR gene copy number was detected in 10.3%. Epidermal growth factor receptor overexpression was associated with hormone receptor negativity and high Ki-67 proliferation index. In survival analyses, EGFR overexpression, but not high EGFR copy number, was associated with poor disease-free survival in all patients, and in the subgroup not receiving adjuvant trastuzumab. In 447 HER2-positive primary breast cancer patients treated with adjuvant trastuzumab, EGFR overexpression was also an independent poor prognostic factor. However, EGFR overexpression was not associated with trastuzumab response, progression-free survival or overall survival in the metastatic setting.

Conclusions:

Epidermal growth factor receptor overexpression, but not high EGFR copy number, is a poor prognostic factor in HER2-positive primary breast cancer. Epidermal growth factor receptor overexpression is a predictive factor for trastuzumab response in HER2-positive primary breast cancer, but not in metastatic breast cancer.

High EGFR gene copy number predicts poor outcome in triple-negative breast cancer

Epidermal growth factor receptor (EGFR) is frequently overexpressed in triple-negative breast cancer and is emerging as a therapeutic target. EGFR gene copy number alteration and mutation are highly variable and scientists have been challenged to define their prognostic significance in triple-negative breast cancer. We examined EGFR protein expression, EGFR gene copy number alteration and mutation of exon 18 to 21 in 151 cases of triple-negative breast cancer and correlated these findings with clinical outcomes. In addition, intratumoral agreement of EGFR protein overexpression and gene copy number alteration was evaluated. EGFR overexpression was found in 97 of 151 cases (64%) and high EGFR gene copy number was detected in 50 cases (33%), including 3 gene amplification (2%) and 47 high polysomy (31%). Five EGFR mutations were detected in 4 of 151 cases (3%) and included G719A in exon 18 (n=1), V786M in exon 20 (n=1), and L858R in exon 21 (n=3). One case had two mutations (G719A and L858R). High EGFR copy number, but not EGFR mutation, correlated with EGFR protein overexpression. Intratumoral heterogeneity of EGFR protein overexpression and EGFR copy number alteration was not significant. In survival analyses, high EGFR copy number was found to be an independent prognostic factor for poor disease-free survival in patients with triple-negative breast cancer. Our findings showed that EGFR mutation was a rare event, but high EGFR copy number was relatively frequent and correlated with EGFR overexpression in triple-negative breast cancer. Moreover, high EGFR copy number was associated with poor clinical outcome in triple-negative breast cancer, suggesting that evaluation of EGFR copy number may be useful for predicting outcomes in patients with triple-negative breast cancer and for selecting patients for anti-EGFR-targeted therapy.

Triple negative breast carcinoma EGFR amplification is not associated with EGFR, Kras or ALK mutations

Background:

The amplification of epidermal growth factor receptor (EGFR) in triple negative breast carcinomas (TNBC) suggests its potential therapeutic application, as for HER-2, using standardised methods of measurement. In this regard, we aimed to compare several methods for evaluating EGFR amplification along with potential mutations for suitability in clinical practice.

Methods:

Tissue sections of 138 TNBCs were used (1) to compare EGFR amplification and expression by silver in situ hybridisation (SISH) to qPCR and immunohistochemistry (IHC) and (2) to search for EGFR mutations, along with Kras, PI3K, Braf and HER-2 mutations and echinoderm microtubule associated protein like 4-anaplastic lymphoma kinase (EML4-ALK) translocation.

Results:

(1) Amplification of EGFR was observed in well-characterised TNBCs (up to 92%); (2) qPCR correlated with SISH with 94% specificity and 75.6% sensitivity; (3) IHC correlated with SISH with 97% sensitivity and 78% specificity; (4) no EGFR, Kras mutations or EML4-ALK translocations were found, but PI3K and Braf mutations were observed in 26% of cases; and (5) small, acentric circular extrachromosomal DNA similar to ‘double minutes' in glioblastomas was observed in 18% of SISH sections.

Conclusions:

SISH and IHC are methods that are suitable in clinical practice to screen for EGFR amplification and overexpression, which are frequently observed in TNBC. Patients with TNBC are potential candidates for EGFR-targeted therapy combined with PI3K and Braf inhibitors.

Cytokeratin 5/6, c-Met expressions, and PTEN loss prognostic indicators in triple-negative breast cancer

In subgroups of breast cancer, the shortest disease-free and overall survival was observed in basaloid and human epidermal growth factor receptor-2 groups. CK5/6 expression is a marker used in diagnosing breast cancers in basaloid group and is associated with a poor prognosis. Similarly, loss of tumor suppressor gene PTEN and a high expression of c-Met has been associated with poor prognosis in breast cancer and many other cancers. In this study, we aimed to determine the effect of CK5/6 and c-Met expressions, and PTEN loss on the disease prognosis in triple-negative breast cancer patients. Ninety-seven patients pathologically diagnosed with triple-negative breast cancer were enrolled. The clinical and pathological characteristics of the patients were recorded. c-Met, PTEN, and CK5/6 expressions were evaluated with immunohistochemical methods from paraffin blocks. The median age of patients was 47 years. CK5/6 positivity was 50.5 %, PTEN loss was 44.3 %, and high c-Met expression was detected in 53.6 %. In multivariate analysis, predictors of the recurrence were loss of PTEN (HR = 2.99; P = 0.004), high c-Met expression (HR = 2.05; P = 0.06), CK5/6 expression (HR = 2.99; P = 0.02), increase in the number of metastatic lymph nodes (HR = 1.11; P = 0.001), and an increase in tumor size (HR = 1.226; P = 0.01). Also, PTEN loss (HR = 2.43; P = 0.05), CK5/6 expression (HR = 3.74; P = 0.01), and N2-3 tumors compared to negatives (HR = 3.63; P = 0.01) were associated with death. PTEN loss correlated with those of lymphovascular invasion. There was a correlation between CK5/6 expression and the number of metastatic lymph nodes. Also, a correlation was found among cancers with highly expressed levels of c-Met, T1-2 tumors, and high-grade tumors. The classical markers, lymph node involvement and tumor size, were found to be of prognostic value; however, high c-Met and CK5/6 expressions, and PTEN loss were found to increase risk of recurrence and death in patients with triple-negative breast cancer.

A survey of immunohistochemical biomarkers for basal-like breast cancer against a gene expression profile gold standard

Gene expression profiling of breast cancer delineates a particularly aggressive subtype referred to as 'basal-like', which comprises ∼15% of all breast cancers, afflicts younger women and is refractory to endocrine and anti-HER2 therapies. Immunohistochemical surrogate definitions for basal-like breast cancer, such as the clinical ER/PR/HER2 triple-negative phenotype and models incorporating positive expression for CK5 (CK5/6) and/or EGFR are heavily cited. However, many additional biomarkers for basal-like breast cancer have been described in the literature. A parallel comparison of 46 proposed immunohistochemical biomarkers of basal-like breast cancer was performed against a gene expression profile gold standard on a tissue microarray containing 42 basal-like and 80 non-basal-like breast cancer cases. Ki67 and PPH3 were the most sensitive biomarkers (both 92%) positively expressed in the basal-like subtype, whereas CK14, IMP3 and NGFR were the most specific (100%). Among biomarkers surveyed, loss of INPP4B (a negative regulator of phosphatidylinositol signaling) was 61% sensitive and 99% specific with the highest odds ratio (OR) at 108, indicating the strongest association with basal-like breast cancer. Expression of nestin, a common marker of neural progenitor cells that is also associated with the triple-negative/basal-like phenotype and poor breast cancer prognosis, possessed the second highest OR at 29 among the 46 biomarkers surveyed, as well as 54% sensitivity and 96% specificity. As a positively expressed biomarker, nestin possesses technical advantages over INPP4B that make it a more ideal biomarker for identification of basal-like breast cancer. The comprehensive immunohistochemical biomarker survey presented in this study is a necessary step for determining an optimized surrogate immunopanel that best defines basal-like breast cancer in a practical and clinically accessible way.

Clinicopathological study of primary gastric lymphomas in the central region of Tunisia, with survival analysis

BACKGROUND

Primary gastric lymphomas (PGL) are rare and represent only 5% of gastric malignancies, but are apparently increasing in incidence worldwide. Optimal treatment of PGL remains controversial. The aim of this study was to evaluate clinicopathological characteristics, prognostic factors, survival rates, and treatment modalities in Tunisian patients with PGL.

METHODS

We retrospectively analyzed data from patients treated for PGL in our hospital over an 18-year period (1994-2011).

RESULTS

Data from 128 patients with PGL were retrospectively analyzed. Eighty-four were males and the median age was 57 years (range 5-89 years). The mean BMI was 22.9 (15-39). A total of 40 patients (31.2%) had a poor performance status (PS). The antrum was the most commonly involved site (52 cases, 40.6%). The most frequent pathological subtypes were diffuse large-cell lymphomas (46.4%) and mucosa-associated lymphoid tissues (32%). Disease was localized (stages IE and IIE) in 97 patients (75.8%). Ninety-six patients were evaluable. Chemotherapy alone was used in 73 (76%) patients, with 76.7% achieving complete remission. During chemotherapy, there were no severe complications requiring urgent surgery. Actuarial five-year overall and event-free survival were 60.2 and 54.3% respectively. We found no statistically significant difference in survival between patients treated with surgery and those treated by a conservative strategy. In the multivariate study, age greater than 60 years, poor PS, and BMI less than 20 were significant prognostic factors for overall survival (P=0.04, 0.009, and <0.001, respectively).

CONCLUSION

Surgery provides no advantage for survival over conservative treatment. Age, PS, and BMI were effective prognostic factors.