Prognostic value of proliferation in invasive breast cancer: a review

Th2 cell infiltrations predict neoadjuvant chemotherapy response of estrogen receptor-positive breast cancer

Background

High infiltration of Th2 is linked to breast cancer progression and metastasis through the induction of cytokine release and T-cell anergy. The estrogen receptor (ER)-positive subtype, which accounts for 70% of breast cancer, is known to respond less to neoadjuvant chemotherapy (NAC) due to its low potential for proliferation. We hypothesized that Th2 high tumors are highly proliferative, and thus more likely to respond to NAC in ER-positive breast cancer.

Methods

We obtained clinicopathological data and overall survival information on 1,069 breast cancer patients from The Cancer Genome Atlas (TCGA). Computational algorithms and CIBERSORT were used to estimate immune cell infiltration. Additionally, xCell was used for validation.

Results

Th2 high tumors did not consistently associate with an unfavorable immune cell composition and tumor immune microenvironment but were found to be significantly elevated in the cancer stage. Th2 high tumors also correlated with high Nottingham pathological grade, as well as with Ki-67 and proliferation score in ER-positive subtypes. High Th2 tumors achieved a pathological complete response (pCR) significantly higher in ER-positive breast cancer.

Conclusions

In conclusion, high levels of Th2 are associated with aggressive features of breast cancer. Th2 levels may be a biomarker in patient selection for NAC in ER-positive breast cancer.

Histological Aspects and Quantitative Assessment of Ki67 as Prognostic Factors in Breast Cancer Patients: Result from a Single-Center, Cross Sectional Study

Background and objectives: Our aim is to explore the relationship between the levels of protein encoded by Ki67 and the histopathological aspects regarding the overall survival and progression-free survival in a single university center. A secondary objective was to examine other factors that can influence these endpoints. New approaches to the prognostic assessment of breast cancer have come from molecular profiling studies. Ki67 is a nuclear protein associated with cell proliferation. Together with the histological type and tumor grade, it is used to appreciate the aggressiveness of the breast tumors. Materials and Methods: We conducted a retrospective single-institution study, at Elias University Emergency Hospital, Bucharest, Romania, in which we enrolled women with stage I to III breast cancer. The protocol was amended to include the immunohistochemistry determination of Ki67 and the histological aspects. The methodology consisted in using a Kaplan-Meier analysis for the entire sample and restricted mean survival time up to 36 months. Results: Both lower Ki67 and low tumor grade are associated with better prognosis in terms of overall survival (OS) and progression-free survival (PFS) for our patients' cohort. In our group, the histological type did not impact the time to progression or survival. Conclusions: Both overall survival and progression-free survival may be influenced by the higher value of Ki67 and less differentiated tumors. Further studies are needed in order to establish if the histologic type may impact breast cancer prognostic, probably together with other histologic and molecular markers.

Single-cell RNA-sequencing reveals distinct patterns of cell state heterogeneity in mouse models of breast cancer

Breast cancer stem cells (BCSCs) contribute to intra-tumoral heterogeneity and therapeutic resistance. However, the binary concept of universal BCSCs co-existing with bulk tumor cells is over-simplified. Through single-cell RNA-sequencing, we found that Neu, PyMT and BRCA1-null mammary tumors each corresponded to a spectrum of minimally overlapping cell differentiation states without a universal BCSC population. Instead, our analyses revealed that these tumors contained distinct lineage-specific tumor propagating cells (TPCs) and this is reflective of the self-sustaining capabilities of lineage-specific stem/progenitor cells in the mammary epithelial hierarchy. By understanding the respective tumor hierarchies, we were able to identify CD14 as a TPC marker in the Neu tumor. Additionally, single-cell breast cancer subtype stratification revealed the co-existence of multiple breast cancer subtypes within tumors. Collectively, our findings emphasize the need to account for lineage-specific TPCs and the hierarchical composition within breast tumors, as these heterogenous sub-populations can have differential therapeutic susceptibilities.

Identifying ultrasound features of positive expression of Ki67 and P53 in breast cancer using radiomics

PURPOSE

To examine the relationship between ultrasonic findings and positive expression of Ki67 and P53 in breast cancer.

MATERIAL AND METHODS

Surgical resection specimens of 263 breast cancer lesions were examined. Ultrasound examination and pathological examination were performed on each lesion for retrospective analysis. We applied regression analysis to the ultrasonic features related to the positive expression of Ki67 and P53 and obtained the corresponding models. To analyze diagnostic efficiency, we calculated the area under the curve (AUC). Additionally, we created a heat map to show the results of the cluster analysis.

RESULTS

Lesions with higher Ki67 expression were associated with posterior acoustic enhancement, absence of an echo halo and a higher Breast Imaging Reporting and Data System (BI-RADS) category. P53-positive cancer were associated with an absence of an echo halo and a higher BI-RADS category. The AUC of the regression models of Ki67 and P53 was 0.78 and 0.71, respectively.

CONCLUSIONS

Our study revealed that breast cancer ultrasonic findings were closely related to expression of molecular indicators, suggesting that ultrasound can be used to provide useful information to clinicians.

Obesity and triple-negative-breast-cancer: Is apelin a new key target?

Epidemiological studies have shown that obese subjects have an increased risk of developing triple‐negative breast cancer (TNBC) and an overall reduced survival. However, the relation between obesity and TNBC remains difficult to understand. We hypothesize that apelin, an adipokine whose levels are increased in obesity, could be a major factor contributing to both tumour growth and metastatization in TNBC obese patients. We observed that development of obesity under high‐fat diet in TNBC tumour‐bearing mice significantly increased tumour growth. By showing no effect of high‐fat diet in obesity‐resistant mice, we demonstrated the necessity to develop obesity‐related disorders to increase tumour growth. Apelin mRNA expression was also increased in the subcutaneous adipose tissue and tumours of obese mice. We further highlighted that the reproduction of obesity‐related levels of apelin in lean mice led to an increased TNBC growth and brain metastases formation. Finally, injections of the apelinergic antagonist F13A to obese mice significantly reduced TNBC growth, suggesting that apelinergic system interference could be an interesting therapeutic strategy in the context of obesity and TNBC.

Mitosis detection in breast cancer histopathology images using hybrid feature space

Breast Cancer grading is a challenging task as regards image analysis, which is normally based on mitosis count rate. The mitotic count provides an estimate of aggressiveness of the tumor. The detection of mitosis is a challenging task because in a frame of slides at X40 magnification, there are hundreds of nuclei containing few mitotic nuclei. However, manual counting of mitosis by pathologists is a difficult and time intensive job, moreover conventional method rely mainly on the shape, color, and/or texture features as well as pathologist experience. The objective of this study is to accept the atypaia-2014 mitosis detection challenge, automate the process of mitosis detection and a proposal of a hybrid feature space that provides better discrimination of mitotic and non-mitotic nuclei by combining color features with morphological and texture features. To exploit color channels, they were first selected, and then normalized and cumulative histograms were computed in wavelet domain. A detailed analysis presented on these features in different color channels of respective color spaces using Random Forest (RF) and Support Vector Machine (SVM) classifiers. The proposed hybrid feature space when used with SVM classifier achieved a detection rate of 78.88% and F-measure of 72.07%. Our results, especially high detection rate, indicate that proposed hybrid feature space model contains discriminant information for mitotic nuclei, being therefore a very capable are for exploration to improve the quality of the diagnostic assistance in histopathology.

Molecular natural history of breast cancer: Leveraging transcriptomics to predict breast cancer progression and aggressiveness

BACKGROUND

Characterizing breast cancer progression and aggressiveness relies on categorical descriptions of tumor stage and grade. Interpreting these categorical descriptions is challenging because stage convolutes the size and spread of the tumor and no consensus exists to define high/low grade tumors.

METHODS

We address this challenge of heterogeneity in patient-specific cancer samples by adapting and applying several tools originally created for understanding heterogeneity and phenotype development in single cells (specifically, single-cell topological data analysis and Wanderlust) to create a continuous metric describing breast cancer progression using bulk RNA-seq samples from individual patient tumors. We also created a linear regression-based method to predict tumor aggressiveness in vivo from bulk RNA-seq data.

RESULTS

We found that breast cancer proceeds along three convergent phenotype trajectories: luminal, HER2-enriched, and basal-like. Furthermore, 31 296 genes (for luminal cancers), 17 827 genes (for HER2-enriched), and 18 505 genes (for basal-like) are dynamically differentially expressed during breast cancer progression. Across progression trajectories, our results show that expression of genes related to ADP-ribosylation decreased as tumors progressed (while PARP1 and PARP2 increased or remained stable), suggesting the potential for a differential response to PARP inhibitors based on cancer progression. Additionally, we developed a 132-gene expression regression equation to predict mitotic index and a 23-gene expression regression equation to predict growth rate from a single breast cancer biopsy.

CONCLUSION

Our results suggest that breast cancer dynamically changes during disease progression, and growth rate of the cancer cells is associated with distinct transcriptional profiles.

Luminal A versus luminal B breast cancer: MammaTyper mRNA versus immunohistochemical subtyping with an emphasis on standardised Ki67 labelling-based or mitotic activity index-based proliferation assessment

AIMS

Proliferation assessment by the use of Ki67 is a crucial component in intrinsic subtyping of luminal breast cancers (BCs), but suffers from variability between laboratories, observers, and methods. MammaTyper is a quantitative molecular tool that measures mRNA levels of ERBB2, ESR1, PGR and MKI67 in BC, and interprets the results according to the St Gallen 2013 consensus recommendations. We compared MammaTyper with immunohistochemistry (IHC)-based subtypes, with a focus on standardised proliferation assessment.

METHODS AND RESULTS

We analysed the agreement in assigning subtypes between MammaTyper and receptor IHC in 101 unifocal luminal HER2-negative early BCs of no special type. Two Ki67 counting protocols, Ki67-Global (Ki67-G) and Ki67-HotSpot (Ki67-H), recommended by the International Ki67 in BC Working Group, and the mitotic activity index (MAI) were used for proliferation assessment. The proportions of BCs identified as luminal A and as luminal B were 55% and 45% for MammaTyper, 55% and 45% for IHC + Ki67-G, 36% and 64% for IHC + Ki67-H, and 56% and 44% for IHC + MAI. The levels of agreement between MammaTyper-based and IHC-based subtyping were 84% (κ = 0.679) for IHC + Ki67-G, 72% (κ = 0.462) for IHC + Ki67-H, and 89% (κ = 0.779) for IHC + MAI.

CONCLUSIONS

High rates of agreement between mRNA-based and IHC-based intrinsic subtyping of luminal HER2-negative BC can be achieved. However, the agreement between IHC-based and MammaTyper-based luminal subtypes depends on the proliferation assessment method, and was highest when the MAI was used. Further comparative clinical studies are needed to determine which method is to be preferred, including analysis of cost-effectiveness.

Development of gemcitabine-resistant patient-derived xenograft models of pancreatic ductal adenocarcinoma

AIM

Gemcitabine is a frontline agent for locally-advanced and metastatic pancreatic ductal adenocarcinoma (PDAC), but neither gemcitabine alone nor in combination produces durable remissions of this tumor type. We developed three PDAC patient-derived xenograft (PDX) models with gemcitabine resistance (gemR) acquired in vivo, with which to identify mechanisms of resistance relevant to drug exposure in vivo and to evaluate novel therapies.

METHODS

Mice bearing independently-derived PDXs received 100 mg/kg gemcitabine once or twice weekly. Tumors initially responded, but regrew on treatment and were designated gemR. We used immunohistochemistry to compare expression of proteins previously associated with gemcitabine resistance [ribonucleotide reductase subunit M1 (RRM1), RRM2, human concentrative nucleoside transporter 1 (hCNT1), human equilibrative nucleoside transporter 1 (hENT1), cytidine deaminase (CDA), and deoxycytidine kinase (dCK)] in gemR and respective gemcitabine-naive parental tumors.

RESULTS

Parental and gemR tumors did not differ in tumor cell morphology, amount of tumor-associated stroma, or expression of stem cell markers. No consistent pattern of expression of the six gemR marker proteins was observed among the models. Increases in RRM1 and CDA were consistent with in vitro-derived gemR models. However, rather than the expected decreases of hCNT1, hENT1, and dCK, gemR tumors expressed no change in or higher levels of these gemR marker proteins than parental tumors.

CONCLUSION

These models are the first PDAC PDX models with gemcitabine resistance acquired in vivo. The data indicate that mechanisms identified in models with resistance acquired in vitro are unlikely to be the predominant mechanisms when resistance is acquired in vivo. Ongoing work focuses on characterizing unidentified mechanisms of gemR and on identifying agents with anti-tumor efficacy in these gemR models.

Breast Cancer 18F-ISO-1 Uptake as a Marker of Proliferation Status

The σ₂ receptor is a potential in vivo target for measuring proliferative status in cancer. The feasibility of using N-(4-(6,7-dimethoxy-3,4-dihydroisoquinolin-2(1H)-yl)butyl)-2-(2-¹⁸F-fluoroethoxy)-5-methylbenzamide (¹⁸F-ISO-1) to image solid tumors in lymphoma, breast cancer, and head and neck cancer has been previously established. Here, we report the results of the first dedicated clinical trial of ¹⁸F-ISO-1 in women with primary breast cancer. Our study objective was to determine whether ¹⁸F-ISO-1 PET could provide an in vivo measure of tumor proliferative status, and we hypothesized that uptake would correlate with a tissue-based assay of proliferation, namely Ki-67 expression. Methods: Twenty-eight women with 29 primary invasive breast cancers were prospectively enrolled in a clinical trial (NCT02284919) between March 2015 and January 2017. Each received an injection of 278-527 MBq of ¹⁸F-ISO-1 and then underwent PET/CT imaging of the breasts 50-55 min later. In vivo uptake of ¹⁸F-ISO-1 was quantitated by SUV_max and distribution volume ratios and was compared with ex vivo immunohistochemistry for Ki-67. Wilcoxon rank-sum tests assessed uptake differences across Ki-67 thresholds, and Spearman correlation tested associations between uptake and Ki-67. Results: Tumor SUV_max (median, 2.0 g/mL; range, 1.3-3.3 g/mL), partial-volume-corrected SUV_max, and SUV ratios were tested against Ki-67. Tumors stratified into the high-Ki-67 (≥20%) group had SUV_max greater than the low-Ki-67 (<20%) group (P = 0.02). SUV_max exhibited a positive correlation with Ki-67 across all breast cancer subtypes (ρ = 0.46, P = 0.01, n = 29). Partial-volume-corrected SUV_max was positively correlated with Ki-67 for invasive ductal carcinoma (ρ = 0.51, P = 0.02, n = 21). Tumor-to-normal-tissue ratios and tumor distribution volume ratio did not correlate with Ki-67 (P > 0.05). Conclusion: ¹⁸F-ISO-1 uptake in breast cancer modestly correlates with an in vitro assay of proliferation.

Association between ultrasound findings, tumor type, grade, and biological markers in patients with breast cancer

Background

This prospective study included 65 female patients with primary breast cancer. Ultrasound was performed for all patients. Ultrasound findings were analyzed according to the ACR BI-RADS lexicon 5th edition and correlated with tumor type, grade, and biological markers (ER, PR, HER-2/neu, and Ki67). The purpose of this study is to assess the association between ultrasound findings, tumor type, grade, and the state of biological markers in patients with breast cancer.

Results

Irregular shape and speculated margins are more frequently associated with invasive duct carcinoma than DCIS (p value < 0.001). There were no association between the ultrasound findings (shape, margin, orientation, echopattern, and posterior features) and the tumor grade (p value 1.0, 0, 0.544, 1.0, and 1.0), respectively. Irregular shape is more frequently seen in ER and PR positive breast cancers (p value = 0.036 and 0.026, respectively). Non-circumscribed margins were frequently seen in PR positive breast cancers (p value = 0.068). No statistically significant difference between US descriptors and HER-2/neu-positive cases.

Conclusion

Irregularly shaped tumors with speculated margins are frequently seen in invasive duct carcinoma and also more frequently seen in ER-, PR-, and Ki67-positive cases. No relation between ultrasound descriptors and the tumor grade of invasive duct carcinoma. Also, there were no relation between ultrasound descriptors and the state of HER-2/neu.

Proliferation Tumour Marker Network (PTM-NET) for the identification of tumour region in Ki67 stained breast cancer whole slide images

Uncontrolled proliferation is a hallmark of cancer and can be assessed by labelling breast tissue using immunohistochemistry for Ki67, a protein associated with cell proliferation. Accurate measurement of Ki67-positive tumour nuclei is of critical importance, but requires annotation of the tumour regions by a pathologist. This manual annotation process is highly subjective, time-consuming and subject to inter- and intra-annotator experience. To address this challenge, we have developed Proliferation Tumour Marker Network (PTM-NET), a deep learning model that objectively annotates the tumour regions in Ki67-labelled breast cancer digital pathology images using a convolution neural network. Our custom designed deep learning model was trained on 45 immunohistochemical Ki67-labelled whole slide images to classify tumour and non-tumour regions and was validated on 45 whole slide images from two different sources that were stained using different protocols. Our results show a Dice coefficient of 0.74, positive predictive value of 70% and negative predictive value of 88.3% against the manual ground truth annotation for the combined dataset. There were minimal differences between the images from different sources and the model was further tested in oestrogen receptor and progesterone receptor-labelled images. Finally, using an extension of the model, we could identify possible hotspot regions of high proliferation within the tumour. In the future, this approach could be useful in identifying tumour regions in biopsy samples and tissue microarray images.

MCM2, MCM4, and MCM6 in Breast Cancer: Clinical Utility in Diagnosis and Prognosis

Breast cancer is a heterogeneous disease comprising the estrogen receptor (ER)-positive luminal subtype which is subdivided into luminal A and luminal B and ER-negative breast cancer which includes the triple-negative subtype. This study has four aims: 1) to examine whether Minichromosome Maintenance (MCM)2, MCM4, and MCM6 can be used as markers to differentiate between luminal A and luminal B subtypes; 2) to study whether MCM2, MCM4, and MCM6 are highly expressed in triple-negative breast cancer, as there is an urgent need to search for surrogate markers in this aggressive subtype, for drug development purposes; 3) to compare the prognostic values of these markers in predicting relapse-free survival; and 4) to compare the three approaches used for scoring the protein expression of these markers by immunohistochemistry (IHC). MCM2, MCM4, MCM6, and MKI67 mRNA expression was first studied using in silico analysis of available breast cancer datasets. We next used IHC to evaluate their protein expression on tissue microarrays using three scoring methods. MCM2, MCM4, and MCM6 can help in distinction between luminal A and luminal B whose therapeutic management and clinical outcomes are different. MCM2, MCM4, MCM6, and Ki-67 are highly expressed in breast cancer of high histological grades that comprise clinically aggressive tumors such as luminal B, HER2-positive, and triple-negative subtypes. Low transcript expression of these markers is associated with increased probability of relapse-free survival. A positive relationship exists among the three scoring methods of each of the four markers. An independent validation cohort is needed to confirm their clinical utility.

The role of regional anesthesia in the propagation of cancer: A comprehensive review

New cancer incidences worldwide will eclipse 18 million in 2019, with nearly 10 million cancer-related deaths. It is estimated that in the United States, almost 40% of individuals will be diagnosed with cancer in their lifetime. Surgical resection of primary tumors remains a cornerstone of cancer treatment; however, the surgical process can trigger an immune-suppressing sympathetic response, which promotes tumor growth of any residual cancerous cells post surgery. Regional and local anesthesia have become staples of anesthesia and analgesia during and after surgery. Recently, much evidence in the form of retrospective and prospective studies has come to light regarding the protective, antitumor properties of anesthetic and analgesic agents across a wide variety of cancers and patient demographics. It is believed that by blocking afferent pain signals, the body does not mount the sympathetic response that contributes to the perpetuation of disease after surgical treatment. This review, therefore, investigates these studies as they pertain to the treatment and outcomes of cancers treated surgically to elucidate the role of regional anesthesia in the propagation of cancer.

Characterization of Kelch domain-containing protein 7B in breast tumours and breast cancer cell lines

Adenocarcinomas exhibit great heterogeneity, with many genetic and epigenetic alterations. The Kelch domain-containing protein 7B (KLHDC7B) has recently been identified as epigenetically modified and upregulated in breast cancer. The potential reversibility of epigenetic states offers exciting possibilities for novel cancer diagnostics and drugs. However, to properly evaluate specific inhibitors, the role of KLHDC7B in the development and progression of breast cancer should be established. With that objective in mind, the present study investigated a series of human breast tumours and correlated their clinicopathology, according to the Elston-Ellis modification of the Scarff-Bloom-Richardson (SBR) grading system, with KLHDC7B mRNA expression, analysed using quantitative PCR (qPCR). The results revealed that KLHDC7B was significantly upregulated in grade 3 tumours, and that KLHDC7B expression varied according to the tumour grade and the individual, being downregulated in well-differentiated and moderately-differentiated tumours (grade 1–2) and upregulated in poorly-differentiated tumours (grade 3). Immunohistochemical staining revealed that ductal tumours and tumours with a higher percentage of Ki67 positive cells showed the highest levels of KLHDC7B. Receptor expression, HER, p53 status, presence of metastasis, and vascular invasion showed no association with KLHDC7B expression. Previous studies have proposed KLHDC7B as an epigenetic marker of breast cancer. We propose that KLHDC7B should be used as a marker for poorly-differentiated tumours only; use of KLHDC7B without considering tumour grade could lead to an inaccurate diagnosis. Finally, we suggest the appropriate breast cancer cell lines to use to determine the functions of KLHDC7B. KLHDC7B expression was tested in the non-tumour cell line MCF-10A and in the breast cancer cell lines MCF-7, MDA-MB-231 and MDA-MB-468, using qPCR and western blotting. The results revealed that all tested cancer cell lines overexpressed KLHDC7B mRNA, but MDA-MB-468 exhibited a much lower level of protein expression relative to mRNA. Although the breast cancer cell lines used may be appropriate for studying KLHDC7B epigenetic status, MDA-MB-468 should be excluded from functional experiments.

Recent advancements in the study of breast cancer exosomes as mediators of intratumoral communication

Breast cancer is a heterogeneous disease, with a morbidity rate of 27.8% and a mortality rate of 15% among women population worldwide. Understanding how this cancer develops and the mechanisms behind tumor progression and chemoresistance is of utmost importance. Exosomes mediate communication in a population of heterogeneous tumoral cells. They have a cargo composed of oncogenes and oncomiRs which change the transcriptomic scenario of their targeted cells and activate numerous tumor-promoting signaling pathways. Exosomes secreted by breast cancer cells lead to enhanced cell proliferation, replicative immortality, angiogenesis, invasion, migration, and chemoresistance. Studying exosomes from this perspective offers more in depth understanding of breast malignancy and may aid in the future development of early diagnostic, prognostic and therapeutic options. We present the latest findings in this area and offer practical solutions which may further stimulate the much-needed research of exosome in breast cancer.

Apelin inhibition prevents resistance and metastasis associated with anti-angiogenic therapy

Angiogenesis is a hallmark of cancer, promoting growth and metastasis. Anti-angiogenic treatment has limited efficacy due to therapy-induced blood vessel alterations, often followed by local hypoxia, tumor adaptation, progression, and metastasis. It is therefore paramount to overcome therapy-induced resistance. We show that Apelin inhibition potently remodels the tumor microenvironment, reducing angiogenesis, and effectively blunting tumor growth. Functionally, targeting Apelin improves vessel function and reduces polymorphonuclear myeloid-derived suppressor cell infiltration. Importantly, in mammary and lung cancer, Apelin prevents resistance to anti-angiogenic receptor tyrosine kinase (RTK) inhibitor therapy, reducing growth and angiogenesis in lung and breast cancer models without increased hypoxia in the tumor microenvironment. Apelin blockage also prevents RTK inhibitor-induced metastases, and high Apelin levels correlate with poor prognosis of anti-angiogenic therapy patients. These data identify a druggable anti-angiogenic drug target that reduces tumor blood vessel densities and normalizes the tumor vasculature to decrease metastases.

Predicting breast tumor proliferation from whole-slide images: The TUPAC16 challenge

Tumor proliferation is an important biomarker indicative of the prognosis of breast cancer patients. Assessment of tumor proliferation in a clinical setting is a highly subjective and labor-intensive task. Previous efforts to automate tumor proliferation assessment by image analysis only focused on mitosis detection in predefined tumor regions. However, in a real-world scenario, automatic mitosis detection should be performed in whole-slide images (WSIs) and an automatic method should be able to produce a tumor proliferation score given a WSI as input. To address this, we organized the TUmor Proliferation Assessment Challenge 2016 (TUPAC16) on prediction of tumor proliferation scores from WSIs. The challenge dataset consisted of 500 training and 321 testing breast cancer histopathology WSIs. In order to ensure fair and independent evaluation, only the ground truth for the training dataset was provided to the challenge participants. The first task of the challenge was to predict mitotic scores, i.e., to reproduce the manual method of assessing tumor proliferation by a pathologist. The second task was to predict the gene expression based PAM50 proliferation scores from the WSI. The best performing automatic method for the first task achieved a quadratic-weighted Cohen's kappa score of κ = 0.567, 95% CI [0.464, 0.671] between the predicted scores and the ground truth. For the second task, the predictions of the top method had a Spearman's correlation coefficient of r = 0.617, 95% CI [0.581 0.651] with the ground truth. This was the first comparison study that investigated tumor proliferation assessment from WSIs. The achieved results are promising given the difficulty of the tasks and weakly-labeled nature of the ground truth. However, further research is needed to improve the practical utility of image analysis methods for this task.

Circular RNA hsa_circ_0072309 inhibits proliferation and invasion of breast cancer cells via targeting miR-492

Background

Although the number of circular RNAs (circRNAs) that has been identified in multiple cancer tissues continues to increase, the relationship between circRNA expression and carcinogenesis remains unknown. The role of hsa_circ_0072309 in breast cancer has remained undefined until now. In this study, we aimed to investigate the role of hsa_circ_0072309 in breast cancer progression.

Methods

hsa_circ_0072309 expression in breast cancer tissues was analyzed using qRT-PCR. A series of functional experiments were carried out to investigate hsa_circ_0072309 function in breast cancer development and its underlying molecular mechanisms.

Results

hsa_circ_0072309 expression in breast cancer tissues was upregulated relative to that in adjacent normal tissues. hsa_circ_0072309 could serve as a prognostic biomarker of breast cancer. hsa_circ_0072309 overexpression dramatically inhibited the proliferation, migration, and invasion of breast cancer cells in vitro. In vivo assays revealed that the ectopic expression of hsa_circ_0072309 repressed breast cancer growth. The results of our mechanistic studies indicated that hsa_circ_0072309 could act as the sponge of miR-492, which exhibited increased expression in breast cancer tissues. Hsa_circ_0072309 suppressed breast cancer cell proliferation, migration, and invasion by inhibiting miR-492.

Conclusion

Our findings revealed for the first time that the hsa_circ_0072309-miR-492 axis plays an essential role in breast cancer progression.

Drug resistance in topoisomerase-targeting therapy

Drug resistance is a well-known phenomenon that occurs when initially responsive to chemotherapy cancer cells become tolerant and elude further effectiveness of anticancer drugs. Based on their mechanism of action, anticancer drugs can be divided into cytotoxic-based agents and target-based agents. An important role among the therapeutics of the second group is played by drugs targeting topoisomerases, nuclear enzymes critical to DNA function and cell survival. These enzymes are cellular targets of several groups of anticancer agents which generate DNA damage in rapidly proliferating cancer cells. Drugs targeting topoisomerase I are mostly analogs of camtothecin, a natural compound isolated from the bark of a tree growing in China. Drugs targeting topoisomerase II are divided into poisons, such as anthracycline antibiotics, whose action is based on intercalation between DNA bases, and catalytic inhibitors that block topoisomerase II at different stages of the catalytic cycle. Unfortunately, chemotherapy is often limited by the induction of drug resistance. Identifying mechanisms that promote drug resistance is critical for the improvement of patient prognosis. Cancer drug resistance is a complex phenomenon that may be influenced by many factors. Here we discuss various mechanisms by which cancer cells can develop resistance to topoisomerase-directed drugs, which include enhanced drug efflux, mutations in topoisomerase genes, hypophosphorylation of topoisomerase II catalytic domain, activation of NF-κB transcription factor and drug inactivation. All these events may lead to the ineffective induction of cancer cell death. Attempts at circumventing drug resistance through the inhibition of cellular efflux pumps, use of silencing RNAs or inhibition of some important mechanisms, which can allow cancer cells to survive therapy, are also presented.

Performance of 4 Immunohistochemical Phosphohistone H3 Antibodies for Marking Mitotic Figures in Breast Cancer

BACKGROUND

Phosphohistone H3 (PHH3) has been suggested to facilitate and improve mitotic activity assessment in breast cancer and other tumor entities, but the reliability of respective immunohistochemical antibodies has not yet been compared for routine purposes. Our aim was to test the performance of 4 different PHH3 antibodies on a series of highly proliferating breast cancers with good preservation of morphology.

METHODS

Four commercially available PHH3 antibodies were tested on 9 grade 3 invasive breast cancers processed in the same batch. We analyzed the number of antibody stained and nonstained mitotic figures as well as the total of cells observed in 10 high power fields per tumor to calculate sensitivity, specificity, and accuracy of the respective antibodies for staining mitotic figures, taking morphologically defined mitotic figures as gold standard.

RESULTS

Sensitivity, specificity, and accuracy of the respective PHH3 antibodies for staining mitotic figures were 54.51%, 99.98%, and 98.79% for Cell Marque, 87.48%, 67.62%, and 67.47% for Epitomics, 98.62%, 99.73%, and 99.49% for Merck 06-570, and 99.74%, 99.52%, and 99.51% for Merck 09-797, respectively. Sensitivity was lowest for telophase. In statistical analysis, the Cell Marque antibody demonstrated significantly lower sensitivity and Epitomics substantially lower sensitivity and specificity than Merck 06-570 and Merck 09-797 antibodies (P<0.0001, respectively).

CONCLUSIONS

Performance and reliability varied significantly between the 4 tested antibodies. For faster identification of mitotic hot spots and as potential marker in digital image analysis, the Merck antibodies seem to be most suitable.

Analysis of cell proliferation and tissue remodelling uncovers a KLF4 activity score associated with poor prognosis in colorectal cancer

BACKGROUND

Human cancers can be classified based on gene signatures quantifying the degree of cell proliferation and tissue remodelling (PR). However, the specific factors that drive the increased tissue remodelling in tumours are not fully understood. Here we address this question using colorectal cancer as a case study.

METHODS

We reanalysed a reported cohort of colorectal cancer patients. The patients were stratified based on gene signatures of cell proliferation and tissue remodelling. Putative transcription factors activity was inferred using gene expression profiles and annotations of transcription factor targets as input.

RESULTS

We demonstrate that the PR classification performs better than the currently adopted consensus molecular subtyping (CMS). Although CMS classification differentiates patients with a mesenchymal signature, it cannot distinguish the remaining patients based on survival. We demonstrate that the missing factor is cell proliferation, which is indicative of good prognosis. We also uncover a KLF4 transcription factor activity score associated with the tissue remodelling gene signature. We further show that the KLF4 activity score is significantly higher in colorectal tumours with predicted infiltration of cells from the myeloid lineage.

CONCLUSION

The KLF4 activity score is associated with tissue remodelling, myeloid cell infiltration and poor prognosis in colorectal cancer.

Whole-Slide Mitosis Detection in H&E Breast Histology Using PHH3 as a Reference to Train Distilled Stain-Invariant Convolutional Networks

Manual counting of mitotic tumor cells in tissue sections constitutes one of the strongest prognostic markers for breast cancer. This procedure, however, is time-consuming and error-prone. We developed a method to automatically detect mitotic figures in breast cancer tissue sections based on convolutional neural networks (CNNs). Application of CNNs to hematoxylin and eosin (H&E) stained histological tissue sections is hampered by noisy and expensive reference standards established by pathologists, lack of generalization due to staining variation across laboratories, and high computational requirements needed to process gigapixel whole-slide images (WSIs). In this paper, we present a method to train and evaluate CNNs to specifically solve these issues in the context of mitosis detection in breast cancer WSIs. First, by combining image analysis of mitotic activity in phosphohistone-H3 restained slides and registration, we built a reference standard for mitosis detection in entire H&E WSIs requiring minimal manual annotation effort. Second, we designed a data augmentation strategy that creates diverse and realistic H&E stain variations by modifying H&E color channels directly. Using it during training combined with network ensembling resulted in a stain invariant mitosis detector. Third, we applied knowledge distillation to reduce the computational requirements of the mitosis detection ensemble with a negligible loss of performance. The system was trained in a single-center cohort and evaluated in an independent multicenter cohort from the cancer genome atlas on the three tasks of the tumor proliferation assessment challenge. We obtained a performance within the top three best methods for most of the tasks of the challenge.

Scinderin-knockdown inhibits proliferation and promotes apoptosis in human breast carcinoma cells

Previous studies have reported that scinderin (SCIN) affects multiple cellular processes, including proliferation, migration and differentiation in cancer. However, the specific role of SCIN in breast cancer (BC) cells is unknown. Immunohistochemistry was used to investigate SCIN expression in 46 BC and 21 mammary fibroadenoma or fibroadenomatoid hyperplasia tissue samples. SCIN expression was ablated in MDA-MB-231 and T-47D cells using lentivirus-mediated small interfering RNA technology. Cell proliferation was tested using Celigo and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. Cell apoptosis was analyzed by measuring Caspase 3/7 activity and annexin-V staining. The results of the present study demonstrated that SCIN expression was elevated in BC tissues compared with mammary fibroadenoma or fibroadenomatoid hyperplasia tissues. Specifically, higher SCIN expression was observed in Ki-67-positive BC tissues (78.6%) compared with Ki-67-negative BC tissues. Furthermore, knockdown of SCIN expression in the BC cell lines significantly suppressed cell proliferation and induced apoptosis. The data presented in the present study indicate that SCIN serves an important role in the development of breast cancer.

Fatty acid oxidation is associated with proliferation and prognosis in breast and other cancers

Background

Altered cellular metabolism is a hallmark of cancer but the association between utilisation of particular metabolic pathways in tumours and patient outcome is poorly understood. We sought to investigate the association between fatty acid metabolism and outcome in breast and other cancers.

Methods

Cox regression analysis and Gene Set Enrichment Analysis (GSEA) of a gene expression dataset from primary breast tumours with well annotated clinical and survival information was used to identify genesets associated with outcome. A geneset representing fatty acid oxidation (FAO) was then examined in other datasets. A doxycycline-inducible breast cancer cell line model overexpressing the rate-limiting enzyme in FAO, carnitine palmitoyl transferase 1A (CPT1A) was generated and analysed to confirm the association between FAO and cancer-associated characteristics in vitro.

Results

We identified a gene expression signature composed of 19 genes associated with fatty acid oxidation (FAO) that was significantly associated with patient outcome. We validated this observation in eight independent breast cancer datasets, and also observed the FAO signature to be prognostic in other cancer types. Furthermore, the FAO signature expression was significantly downregulated in tumours, compared to normal tissues from a variety of anatomic origins. In breast cancer, the expression of CPT1A was higher in oestrogen receptor (ER)-positive, compared to ER-negative tumours and cell lines. Importantly, overexpression of CPT1A significantly decreased the proliferation and wound healing migration rates of MDA-MB231 breast cancer cells, compared to basal expression control.

Conclusions

Our findings suggest that FAO is downregulated in multiple tumour types, and activation of this pathway may lower cancer cell proliferation, and is associated with improved outcomes in some cancers.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4626-9) contains supplementary material, which is available to authorized users.

Mitotic count can predict tamoxifen benefit in postmenopausal breast cancer patients while Ki67 score cannot

Background

Controversy exists for the use of Ki67 protein expression as a predictive marker to select patients who do or do not derive benefit from adjuvant endocrine therapy. Whether other proliferation markers, like Cyclin D1, and mitotic count can also be used to identify those estrogen receptor α (ERα) positive breast cancer patients that derive benefit from tamoxifen is not well established. We tested the predictive value of these markers for tamoxifen benefit in ERα positive postmenopausal breast cancer patients.

Methods

We collected primary tumor blocks from 563 ERα positive patients who had been randomized between tamoxifen (1 to 3 years) vs. no adjuvant therapy (IKA trial) with a median follow-up of 7.8 years. Mitotic count, Ki67 and Cyclin D1 protein expression were centrally assessed by immunohistochemistry on tissue microarrays. In addition, we tested the predictive value of CCND1 gene copy number variation using MLPA technology. Multivariate Cox proportional hazard models including interaction between marker and treatment were used to test the predictive value of these markers.

Results

Patients with high Ki67 (≥5%) as well as low (< 5%) expressing tumors equally benefitted from adjuvant tamoxifen (adjusted hazard ratio (HR) 0.5 for both groups)(p for interaction 0.97). We did not observe a significant interaction between either Cyclin D1 or Ki67 and tamoxifen, indicating that the relative benefit from tamoxifen was not dependent on the level of these markers. Patients with tumors with low mitotic count derived substantial benefit from tamoxifen (adjusted HR 0.24, p <  0.0001), while patients with tumors with high mitotic count derived no significant benefit (adjusted HR 0.64, p = 0.14) (p for interaction 0.03).

Conclusion

Postmenopausal breast cancer patients with high Ki67 counts do significantly benefit from adjuvant tamoxifen, while those with high mitotic count do not. Mitotic count is a better selection marker for reduced tamoxifen benefit than Ki67.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4516-1) contains supplementary material, which is available to authorized users.

Presentation of the Molecular Subtypes of Breast Cancer Detected By Immunohistochemistry in Surgically Treated Patients

INTRODUCTION

The detection of estrogen, progesterone and HER-2 neu receptors on the surface of the tumour cell is a significant prognostic factor, alone or in combination. The presence or absence of receptors on the surface of the tumour cell is associated with the conditional gene expression in the tumour cell itself. Based on these genetically determined expressions of the tumour cell, five molecular subtypes of breast cancer have been classified on the St. Gallen International Expert Consensus in 2011 that can be immunohistochemically detected, with each subtype manifesting certain prognosis and aggression.

AIM

Analyzing the presentation of molecular subtypes of breast cancer that are immunohistochemically detected in surgically treated patients at the Clinic for Thoracic and Vascular Surgery.

MATERIAL AND METHODS

We used the international classification on molecular subtypes of breast cancer which divides them into: Luminal A (ER+ and/or PR+, HER-2 negative, Ki-67 < 14%), Luminal B with HER-2 negative (ER+ and/or PR+, HER-2 negative, Ki-67 ≥ 14%), Luminal B with HER-2 positive (ER+ and/or PR+, HER-2+, any Ki-67), HER-2 enriched (ER-, PR-, HER-2+), and basal-like (triple negative) (ER-, PR-, HER-2 negative, CK5/6+ and/or EGFR+). A total of 290 patients, surgically treated for breast cancer, were analysed during 2014.

RESULTS

In our analysis, we found that Luminal A was present in 77 (26.55%) patients, Luminal B HER-2 negative was present in 91 (31.38%) patients, Luminal B HER-2 positive was present in 70 (24.14%) patients, HER-2 enriched was present in 25 (8.62%) patients and basal-like (or triple negative) was present in 27 (9.31%) patients.

CONCLUSION

Detecting the subtype of breast cancer is important for evaluating the prognosis of the disease, but also for determining and providing an adequate therapy. Therefore, determining the subtype of breast cancer is necessary for the routine histopathological assay.

Downregulation of aquaporin 3 inhibits cellular proliferation, migration and invasion in the MDA-MB-231 breast cancer cell line

Aquaporins are membrane proteins that regulate cellular water flow. Recently, aquaporins have been proposed as mediators of cancer cell biology. A subset of aquaporins, referred to as aquaglyceroporins are known to facilitate the transport of glycerol. The present study describes the effect of gene knockdown of the aquaglyceroporin AQP3 on MDA-MB-231 breast cancer cell proliferation, migration, invasion, adherence and response to the chemotherapeutic agent 5-fluorouracil. shRNA mediated AQP3 gene knockdown induced a 28% reduction in cellular proliferation (P<0.01), a 39% decrease in migration (P<0.0001), a 24% reduction in invasion (P<0.05) and a 25% increase in cell death at 100 µM 5-FU (P<0.01). Analysis of cell permeability to water and glycerol revealed that MDA-MB-231 cells with knocked down AQP3 demonstrated a modest decrease in water permeability (17%; P<0.05) but a more marked decrease in glycerol permeability (77%; P<0.001). These results suggest that AQP3 has a role in multiple aspects of breast cancer cell pathophysiology and therefore represents a novel target for therapeutic intervention.

Proliferative Index in Invasive Tumor Front of Oral Squamous Cell Carcinoma: A Potential Prognostic Indicator

AIM

The aim of the study was to evaluate the proliferative index (PI) at their invasive front of oral cancer and their association with Bryne's grades of oral squamous cell carcinoma (OSCC) and compare the PI with lymph node metastasis, site of involvement, and habits.

MATERIALS AND METHODS

The Ki-67 antigen expression was immunohistochemically evaluated in a total of 102 cases that included the histopathologically diagnosed archival specimens of OSCCs. They were subdivided by Bryne's histopathological grading into grade I (40 cases), grade II (32 cases), and grade III (30 cases). The nucleus with brown stain was considered positive. Cells were counted under 400× magnification. The proliferative activity thus determined was then expressed as a percentage of Ki-67 labeling index (Ki-67 LI) positive cells.

RESULTS

A stepwise increase in the mean Ki-67 LI was found from grade I to III squamous cell carcinoma, thus correlating with the histological grading. In addition, there was a higher PI seen in cases associated with metastatic lymph node, which concords with the higher biologic aggressiveness and poor prognosis of the lesion.

CONCLUSION

The present study shows a definitive correlation of Ki-67 antigen with the Bryne's histological grading, all the parameters of Bryne's grading for OSCC and lymph node status of the patient proving its association as an effective tool to grade the tumors and finally read the prognosis of the tumor.

CLINICAL SIGNIFICANCE

Cell proliferation is regarded as one of the most important biologic mechanisms in oncogenesis. The role of cell proliferation in tumor progression has been inferred in studies concerned with human cancer by comparing the PI of normal tissue, preneoplastic and neoplastic lesions. The Ki-67 antigen-labeled cells can prove to be an effective aid to grade the tumors. It might be possible to standardize and objectify tumor grading among pathology laboratories.

Promotional effect of microRNA-194 on breast cancer cells via targeting F-box/WD repeat-containing protein 7

Breast cancer is the most common type of malignant cancer in females. An increasing number of studies have revealed that microRNAs (miR), which belong to a class of small non-coding RNAs, serve an important role in a number of human cancer subtypes. In the present study, the role of miR-194 in breast cancer cells and its underlying mechanisms were investigated. The results demonstrated that the serum levels of miR-194 were significantly higher in patients of the poorly differentiated and well-differentiated groups, compared with in healthy adults. Additionally, the serum level of miR-194 was significantly higher in the poorly differentiated group compared with in the well-differentiated group. In order to further investigate the role of miR-194 in breast cancer cells, the present study transfected two breast cancer cell lines, MCF-7 and MDA-MB-231, with an empty vector (control), miR-194 (overexpression), antagomiR-194 (inhibitor, functional knock down) or antagomiR-194 and miR-194. An MTT assay was performed in order to detect the proliferation of breast cancer cells in the various groups. The results revealed that the overexpression of miR-194 significantly accelerated cell proliferation, whereas the inhibition of miR-194 significantly decelerated the proliferation of MCF-7 and MDA-MB-231 cells. Furthermore, the expression levels of cyclin D and cyclin E were significantly upregulated in miR-194 overexpressing cells, and the expression levels of cyclin D and cyclin E were significantly downregulated in miR-194 inhibited cells, as compared with in control cells. No significant change was observed in the level of proliferation of cells co-transfected with miR-194 and antagomiR-194, compared with in the control cells. According to the hypothesis suggesting possible target genes of miR-194, the present study proposed that F-box/WD repeat-containing protein 7 (Fbxw-7) may be a direct target of miR-194, which was confirmed by a luciferase reporter assay. The present study suggested that miR-194 expression promoted the proliferation of breast cancer cells by targeting Fbxw-7, and may serve as a biomarker and a novel target for breast cancer therapy.

Impact of Size of the Tumour, Persistence of Estrogen Receptors, Progesterone Receptors, HER2Neu Receptors and Ki67 Values on Positivity of Axillary Lymph Nodes in Patients with Early Breast Cancer with Clinically Negative Axillary Examination

AIM:

The study aimed to identify factors that influence the positivity of axillary lymph nodes in patients with early breast cancer and clinically negative axillary lymph nodes, who were subjected for modified radical mastectomy and axillary lymphadenectomy.

MATERIAL AND METHODS:

This study included 81 surgically treated, early breast cancer patients during the period from 08-2015 to 05-2017. All the cases have been analysed by standard histological analysis including macroscopic and microscopic examination by routine H&E staining. For determination of molecular receptors, immunostaining by PT LINK immunoperoxidase has been done for HER2neu, ER, PR, p53 and Ki67.

RESULTS:

Patients age ranged between 31-73 years, an average of 56.86 years. The mean size of a primary tumour in the surgically treated patient was 20.33 ± 6.0 mm. Axillary dissection revealed from 5 to 32 lymph nodes, with an average of 14. Metastases have been found in 1 to 7 lymph nodes, with an average 0.7. Only 26 (32.1%) of the patients showed metastases in the axillary lymph nodes. The univariant regression analysis showed that the size of a tumour and presence of HER2neu receptors on cancer cells influence the positivity of the axillary lymph nodes. The presence of the estrogen receptors, progesterone receptors have no influence on the positivity for metastatic deposits of lymph nodes. Multivariant model and logistic regression analysis as significant independent factors or predictors of positivity of the axillary lymph nodes are influenced by the tumour size only.

CONCLUSION:

Our study showed that the metastatic involvement of the axillary lymph nodes is mainly influenced by the size of a tumour and presence of HER2neu receptors in the univariant analysis. This point to the important influence of positivity of the axillary lymph nodes but, in multi-variant regressive analysis the lymph node status correlates with the tumour size only.

The Reliability of Core-Needle Biopsy in Assessment of Hormone Receptor, HER2, and Ki-67 in Breast Carcinoma

Objective:

The purpose of this study was to compare the estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor 2 (HER2) status and Ki-67 index by immunohistochemical (IHC) analysis in breast carcinoma to determine the level of concordance between core-needle biopsy (CNB) and surgical specimens.

Summary of Background:

Accurate preoperative diagnosis of a breast lesion has recently been considered essential to the treatment strategy to achieve optimal treatment without delay. However, the reliability of using CNB specimens for IHC assessment is in relatively small number of cases and differing results between previous studies.

Methods:

The patients included in this study were 255 patients with primary breast carcinoma who had CNB and subsequent surgical resection at the Hospital of Dokkyo Medical University between 2010 and 2016. We compare the ER, PgR, HER2 status, and Ki-67 index by IHC analysis in breast carcinoma between CNB and surgical specimens.

Results:

There was a concordance rate between the ER, PgR, HER2, and Ki-67 IHC assessment of CNB and surgical specimens in 99.0%, 92.1%, 86.3%, and 91.5%, respectively. We also found small numbers of discordant cases in the estimation for which a discrepancy in determination led to a change in treatment.

Conclusions:

Our results do not entirely invalidate the use of CNB for assessment if they are the only source of tumor tissue available, but suggest a more cautious approach in their interpretation when clinical decisions are being made.

Interlaboratory variability of Ki67 staining in breast cancer

BACKGROUND

Postanalytic issues of Ki67 assessment in breast cancers like counting method standardisation and interrater bias have been subject of various studies, but little is known about analytic variability of Ki67 staining between pathology labs. Our aim was to study interlaboratory variability of Ki67 staining in breast cancer using tissue microarrays (TMAs) and central assessment to minimise preanalytic and postanalytic influences.

METHODS

Thirty European pathology labs stained serial slides of a TMA set of breast cancer tissues with Ki67 according to their routine in-house protocol. The Ki67-labelling index (Ki67-LI) of 70 matched samples was centrally assessed by one observer who counted all cancer cells per sample. We then tested for differences between the labs in Ki67-LI medians by analysing variance on ranks and in proportions of tumours classified as luminal A after dichotomising oestrogen receptor-positive cancers into cancers showing low (<14%, luminal A) and high (≥14%, luminal B HER2 negative) Ki67-LI using Cochran's Q.

RESULTS

Substantial differences between the 30 labs were indicated for median Ki67-LI (0.65%-33.0%, p < 0.0001) and proportion of cancers classified as luminal A (17%-57%, p < 0.0001). The differences remained significant when labs using the same antibody (MIB-1, SP6, or 30-9) were analysed separately or labs without prior participation in external quality assurance programs were excluded (p < 0.0001, respectively).

CONCLUSION

Substantial variability in Ki67 staining of breast cancer tissue was found between 30 routine pathology labs. Clinical use of the Ki67-LI for therapeutic decisions should be considered only fully aware of lab-specific reference values.

CKAP2 (cytoskeleton-associated protein2) is a new prognostic marker in HER2-negative luminal type breast cancer

Background

Recently, we reported cytoskeleton-associated protein2 (CKAP2) as a possible new prognostic breast cancer marker. However, it has not yet been applied in clinic. Therefore, clinical significance of CKAP2 was evaluated in comparison with that of Ki-67 in a cohort of breast cancer patients, and the expression difference was analyzed in cell cycle-arrested cancer and fibroblast cells.

Methods

A total of 579 early breast cancer patients who underwent surgery at the National Cancer Center Hospital in Korea between 2001 and 2005 were accrued. CKAP2-positive cell count (CPCC) and Ki-67 labeling index (Ki-67LI) were evaluated by immunohistochemcal staining. The immunocytochemical staining patterns of CKAP2 and Ki-67 were analyzed in HeLa and human fibroblast cells after synchronization by double thymidine block.

Results

Although there was a significant correlation (R = 0.754, P < 0.001) between CPCC and Ki-67LI, only CPCC was correlated with DFS in overall population (HR, 2.029; 95% CI, 1.012–4.068; P = 0.046) and HER2-negative luminal subgroup (HR, 3.984; 95% CI, 1.350–11.762; P = 0.012) by multivariate analysis. In immunocytochemical staining, more than 50% of serum-starved or non-mitotic cell phase HeLa cells were positive for Ki-67, in comparison to the low CKAP2-positivity, which might explain the prognostic difference between CPCC and Ki-67LI.

Conclusions

The current study showed that CPCC but not Ki-67LI is an independent prognostic indicator in early breast cancer, more specifically in HER2-negative luminal breast cancer. The difference between two markers may be related to the lower background expression of CKAP2 in cancer cells.

Identification of breast cancer prognostic modules based on weighted protein-protein interaction networks

Breast cancer is one of the leading causes of mortality in females. A number of prognostic markers have been identified, including single genes, multi-gene signatures and network modules; however, the robustness of these prognostic markers is insufficient. Thus, the present study proposed a more robust method to identify breast cancer prognostic modules based on weighted protein-protein interaction networks, by integrating four sets of disease-associated expression profiles. Three identified prognostic modules were closely associated with prognosis-associated functions and survival time, as determined by Cox regression and Kaplan-Meier survival analyses. The robustness of these modules was verified with an independent profile from another platform. Genes from these modules may be useful as breast cancer prognostic markers. The prognostic modules could be used to determine the prognoses of patients with breast cancer and characterize patient recovery.

The value of phosphohistone H3 as a proliferation marker for evaluating invasive breast cancers: A comparative study with Ki67

Background

Established measurements of proliferation in breast cancer are Ki67 and mitotic-activity-index (MAI), with problems in reproducibility and prognostic accuracy. Phosphohistone H3 (PHH3), a relatively novel IHC marker is specific for mitosis with good reproducibility. We hypothesized that PHH3 would be more reproducible and better represent proliferation than Ki67.

Results

PHH3 identified easily-missed mitosis by MAI, as demonstrated by upgrading M grade at diagnosis (n = 29/218, evenly distributed). PHH3 accurately found hot-spots, supported by mitotic count agreement between low-power and 10HPFs (R² = 0.999; P = 0.001). PHH3 was more reproducible than Ki67, measured by five-rater inter-class correlation coefficient (0.904 > 0.712; P = 0.008). Finally, despite a relatively short follow-up (median 46 months; 7 recurrences) PHH3 was the only variable correlated with disease-free survival (P = 0.043), while all other conventional clinicopathologic variables, including Ki67 (P = 0.356), did not.

Materials and Methods

We compared Ki67 and PHH3 for 218 breast cancer surgical cases diagnosed from 2012 to 2013 at Severance hospital. The most representative invasive breast cancer surgical slides were immunohistochemically stained for Ki67 and PHH3.

Conclusions

Poor reproducibility and inadequate representation of proliferation of Ki67 and MAI may be improved by PHH3, allowing better accuracy in breast cancer diagnostics.

MCM2: An alternative to Ki-67 for measuring breast cancer cell proliferation

Breast cancer is a heterogeneous disease comprising a diversity of tumor subtypes that manifest themselves in a wide variety of clinical, pathological, and molecular features. One important subset, luminal breast cancers, comprises two clinically distinct subtypes luminal A and B each of them endowed with its own genetic program of differentiation and proliferation. Luminal breast cancers were operationally defined as follows: Luminal A: ER+, PR+, HER2-, Ki-67<14% and Luminal B: ER+ and/or PR+, HER2-,Ki-67≥14% or, alternatively ER+ and/or PR+, HER2+, any Ki-67. There is currently a need for a clinically robust and validated immunohistochemical assay that can help distinguish between luminal A and B breast cancer. MCM2 is a family member of the minichromosome maintenance protein complex whose role in DNA replication and cell proliferation is firmly established. As MCM2 appears to be an attractive alternative to Ki-67, we sought to study the expression of MCM2 and Ki-67 in different histological grades and molecular subtypes of breast cancer focusing primarily on ER-positive tumors. MCM2 and Ki-67 mRNA expression were studied using in silico analysis of available DNA microarray and RNA-sequencing data of human breast cancer. We next used immunohistochemistry to evaluate protein expression of MCM2 and Ki-67 on tissue microarrays of invasive breast carcinoma. We found that MCM2 and Ki-67 are highly expressed in breast tumors of high histological grades, comprising clinically aggressive tumors such as triple-negative, HER2-positive and luminal B subtypes. MCM2 expression was detected at higher levels than that of Ki-67 in normal breast tissues and in breast cancers. The bimodal distribution of MCM2 scores in ER+/HER2- breast tumors led to the identification of two distinct subgroups with different relapse-free survival rates. In conclusion, MCM2 expression can help sorting out two clinically important subsets of luminal breast cancer whose treatment and clinical outcomes are likely to diverge.

Sex-related differences of urethane and sodium valproate effects on Ki-67 expression in urethane-induced lung tumors of mice

The aim of the present study was to evaluate sex differences in tumorigenesis by assessing the number of Ki-67-positive cells [Ki-67(+)] in urethane-induced mice lung tumors and the effect of sodium valproate (NaVP) in BALB/c mice. Gonad-intact and gonadectomized female and male mice were divided into the following groups: i) Treated with urethane, ii) treated with urethane and NaVP and iii) gonad-intact or gonadectomized control. Urethane (total 50 mg/mouse) was injected intraperitoneally. The NaVP 0.4% solution was administered orally for 6 months. Histologically, lung tumors were divided into adenomas and adenocarcinomas and assessed immunohistochemically using antibodies against Ki-67. The Ki-67(+) was calculated per one mm² of a tumor. In adenomas, Ki-67(+) in the urethane-treated gonad-intact males was significantly higher than in females (P=0.001) and in castrated males (P<0.01); Ki-67(+) in adenomas of the urethane-treated gonad-intact males was significantly higher than in urethane-NaVP-treated ones (P<0.04). No significant differences were found in analogous female groups. In adenocarcinomas, Ki-67(+) in urethane-treated gonad-intact males was significantly higher than in females and gonadectomized mice of both sexes (P<0.001), and in ovariectomized females was significantly higher than in ovary-intact group (P=0.01). A significantly higher number of Ki-67(+) cells were observed in gonad-intact adenocarcinomas of the urethane-NaVP-treated females compared with the urethane-treated ones (P<0.001). Comparing between urethane-NaVP-treated gonadectomized males and females in adenocarcinomas, determined that Ki-67(+) was significantly lower in females (P=0.005). In adenocarcinomas, Ki-67(+) in urethane-NaVP-treated gonadectomized males and females was significantly lower than in gonad-intact mice of the same sex (P<0.001). In summary, gonadectomy with NaVP treatment decreased Ki-67(+) in adenocarcinomas for mice of both sexes. The results of the present study indicate sex-related differences in mice lung tumorigenesis, and a sex-related effect of NaVP on progression in urethane-induced BALB/c mice lung tumors.

Prognostic Factors on the Positivity for Metastases of the Axillary Lymph Nodes from Primary Breast Cancer

AIM

The aim of the study was to identify the impact of T stage, the presence of estrogen, progesterone, HER2neu receptors and the values of the Ki67 on the positivity for metastases of the axillary lymph nodes, from primary breast cancer.

MATERIAL AND METHODS

290 surgically treated patients for breast cancer were included in the study. All cases have been analyzed by standard histological analysis including microscopic analysis on standard H&E staining. For determining the molecular receptors - HER2neu, ER, PR, p53 and Ki67, immunostaining by PT LINK immunoperoxidase has been done.

RESULTS

Patients age was ranged between 18-90 years, average of 57.6+11.9. The mean size of the primary tumor in the surgically treated patient was 30.27 + 18.3 mm. On dissection from the axillary pits 8 to 39 lymph nodes were taken out, an average of 13.81+5.56. Metastases have been found in 1 to 23 lymph nodes, an average 3.14+4.71. In 59% of the patients there have been found metastases in the axillary lymph nodes. The univariate regression analysis showed that the location, size of tumor, differentiation of the tumor, stage, the value of the Ki67 and presence of lymphovascular invasion influence on the positivity of the axillary lymph nodes. The presence of the estrogen receptors, progesterone receptors and HER2neu receptors showed that they do not have influence on the positivity for metastatic deposits in axillary lymph nodes. The multivariate model and the logistic regression analysis as independent significant factors or predictors of positivity of the axillary lymph nodes are influenced by the tumor size and the positive lymphovascular invasion.

CONCLUSION

Our study showed that the involving of the axillary lymph nodes is mainly influenced by the size of the tumor and the presence of lymphovascular invasion in the tumor. Ki67 determined proliferative index in the univariate analysis points the important influence of positivity in the axillary lymph nodes, but not in the multivariate regressive analysis.