The role of CD44+/CD24-/low biomarker for screening, diagnosis and monitoring of breast cancer

Primary cancer-associated fibroblasts exhibit high heterogeneity among breast cancer subtypes

Background

Cancer-associated fibroblasts (CAFs) are a diverse subset of cells, that is recently gaining in popularity and have the potential to become a new target for breast cancer (BC) therapy; however, broader research is required to understand their mechanisms and interactions with breast cancer cells. The goal of the study was to isolate CAFs from breast cancer tumour and characterise isolated cell lines. We concentrated on numerous CAF biomarkers that would enable their differentiation.

Materials and methods

Flow cytometry, immunofluorescence, and reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) were used to phenotype the primary CAFs.

Results/Conclusions

According to our findings, there was no significant pattern in the classification of cancer-associated fibroblasts. The results of biomarkers expression were heterogeneous, thus no specific subtypes were identified. Furthermore, a comparison of cancer-associated fibroblasts derived from different BC subtypes (luminal A and B, triple-negative, HER2 positive) did not reveal any clear trend of expression.

Evaluation of CD44+/CD24- and Aldehyde Dehydrogenase Enzyme Markers in Cancer Stem Cells as Prognostic Indicators for Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) has been extensively studied not just for its aggressive behavior but also to understand its complex molecular nature. This type of heterogeneous tumor shows no expression of estrogen receptor (ER) or progesterone receptor (PR) and does not express the HER2 gene, and often these tumors are high grade with distinct histological groups. The basal-like subtype is most commonly related to the TNBC type of neoplasms; it can be further classified according to Lehmann and Burstein expert’s criteria. TNBC is related to breast stem cell markers such as CD44+/CD24- and high levels of enzyme aldehyde dehydrogenase (ALDH), which have been shown to possess stem cell features that are involved in differentiation, vascular invasion, tumorigenesis, and metastatic potential. CD44+/CD24- and high levels of ALDH have significance as markers as well as indicators of poor prognosis in TNBC. The databases used in this review are PMC, PubMed, and Google Scholar.

Targeted Drug Therapy to Overcome Chemoresistance in Triple-negative Breast Cancer

Triple-negative Breast Cancer (TNBC) is the most aggressive and prevailing breast cancer subtype. The chemotherapeutics used in the treatment of TNBC suffer from chemoresistance, dose-limiting toxicities and off-target side effects. As a result, conventional chemotherapeutics are unable to prevent tumor growth, metastasis and result in failure of therapy. Various new targets such as BCSCs surface markers (CD44, CD133, ALDH1), signaling pathways (IL-6/JAK/STAT3, notch), pro and anti-apoptotic proteins (Bcl-2, Bcl-xL, DR4, DR5), hypoxic factors (HIF-1α, HIF-2α) and drug efflux transporters (ABCC1, ABCG2 and ABCB1) have been exploited to treat TNBC. Further, to improve the efficacy and safety of conventional chemotherapeutics, researchers have tried to deliver anticancer agents specifically to the TNBCs using nanocarrier based drug delivery. In this review, an effort has been made to highlight the various factors responsible for the chemoresistance in TNBC, novel molecular targets of TNBC and nano-delivery systems employed to achieve sitespecific drug delivery to improve efficacy and reduce off-target side effects.

Particle Therapy for Breast Cancer: Benefits and Challenges

Hadron therapy with protons and carbon ions is widely attracting interest as a potential competitor of conventional photon radiotherapy. Exquisite dose distribution of charged particles allows for a higher local control of the tumor and lower probability of damage to nearby healthy tissues. Heavy ions have presumed biological advantages rising from their high-linear energy transfer (LET) characteristics, including greater cell-killing effectiveness and reduced heterogeneity dependence of radiation response. Although these advantages are clear and supported by data, only 18.0% of proton and carbon ion radiotherapy (CIRT) facilities in Europe are treating breast cancers. This review summarizes the physical and radiobiological properties of charged particles, clinical use of particle beam for breast cancer, and suggested approaches to overcome technical and financial challenges.

Breast Cancer Stem Cells: Biomarkers, Identification and Isolation Methods, Regulating Mechanisms, Cellular Origin, and Beyond

Despite recent advances in diagnosis and treatment, breast cancer (BC) is still a major cause of cancer-related mortality in women. Breast cancer stem cells (BCSCs) are a small but significant subpopulation of heterogeneous breast cancer cells demonstrating strong self-renewal and proliferation properties. Accumulating evidence has proved that BCSCs are the driving force behind BC tumor initiation, progression, metastasis, drug resistance, and recurrence. As a heterogeneous disease, BC contains a full spectrum of different BC subtypes, and different subtypes of BC further exhibit distinct subtypes and proportions of BCSCs, which correspond to different treatment responses and disease-specific outcomes. This review summarized the current knowledge of BCSC biomarkers and their clinical relevance, the methods for the identification and isolation of BCSCs, and the mechanisms regulating BCSCs. We also discussed the cellular origin of BCSCs and the current advances in single-cell lineage tracing and transcriptomics and their potential in identifying the origin and lineage development of BCSCs.

Predictive Value of CD44 for Prognosis in Patients with Breast Cancer

Background:

Breast Cancer (BC), is one of the most common malignancies around the world. CD44 expression correlates with cell proliferation, infiltration, angiogenesis, metastasis and prognosis in breast cancer but the exact mechanism of CD44 function is still not clear. The present study evaluates the expression of CD44 in primary HER2-positive breast cancer. The results can be used to determine the disease-free and overall survival of patients with breast cancer.

Methods:

We studied specimens from 100 patients with HER2-positive invasive breast cancer between March 2011 and June 2019. Immunohistochemical staining for CD44 was performed in all the specimens. Their CD44 association with clinicopathologic parameters and prognosis was evaluated.

Results:

The high CD44 was expression in 68(68%) of the patients and Low expression in 32(32%). CD44 expression was significantly associated with stage (p=0.007). There were no significant associations between the DFS, OS and other clinicopathologic parameters except for the stage, respectively (HR= 3.67, 95% CI =1.16-11.56, P = 0.03) (HR= 0.8.56, 95% CI =2.22-32.90, P = 0.002).20% of patients had died by the end of the follow-up. There were no significant association between DFS, OS and CD44 expression, respectively. (Log-rank p=0.13). (Log-rank p=0.10).

Conclusion:

The results from this study suggest that CD44 is clinically associated with stage of breast cancers. From the survival analysis, there was no statistical difference in overall survival and disease free survival with respect to CD44 expression. Further studies larger sample sizes are recommended for further investigation.

Role of Cancer Stem Cells in Cholangiocarcinoma and Therapeutic Implications

Cholangiocarcinoma (CCA) is the second most common type of liver cancer, and is highly aggressive with very poor prognosis. CCA is classified into intrahepatic cholangiocarcinoma (iCCA) and extra-hepatic cholangiocarcinoma (eCCA), which is further stratified into perihilar (pCCA) and distal (dCCA). Cancer stem cells (CSCs) are a subpopulation of cancer cells capable of tumor initiation and malignant growth, and are also responsible for chemoresistance. Thus, CSCs play an important role in CCA carcinogenesis. Surface markers such as CD133, CD24, CD44, EpCAM, Sox2, CD49f, and CD117 are important for identifying and isolating CCA CSCs. CSCs are present in the tumor microenvironment (TME), termed ‘CSC niche’, where cellular components and soluble factors interact to promote tumor initiation. Epithelial-to-mesenchymal transition (EMT) is another important mechanism underlying carcinogenesis, involved in the invasiveness, metastasis and chemoresistance of cancer. It has been demonstrated that EMT plays a critical role in generating CSCs. Therapies targeting the surface markers and signaling pathways of CCA CSCs, proteins involved in TME, and immune checkpoint proteins are currently under investigation. Therefore, this review focuses on recent studies on the roles of CSCs in CCA; the possible therapeutic strategies targeting CSCs of CCA are also discussed.

Cellular communication promotes mammosphere growth and collective invasion through microtubule‑like structures and angiogenesis

Networks of nanotubes and microtubules are highly valued in cellular communication, and collective cancer movement has been revealed to be associated with cell information exchange. In the present study, cellular communication was demonstrated to participate in mammosphere growth, differentiation and collective invasion. By promoting differentiation, networks of cells and microtubule-like structures were verified. Analyses of cell cycle progression, stemness markers and gene expression indicated that mammospheres had collective characteristics of stemness and differentiation. Invasion assays revealed that networks of microtubule-like structures promoted collective invasion. Conversely, using anti-angiogenic intervention, the growth of stem-like mammospheres and cellular communication links were effectively inhibited. In vivo experiments revealed that cellular communication promoted tumor growth and metastasis through the formation of nodular fusion, cluttered microtubule-like structures and cancer stem cells, as well as vascular niches. In conclusion, the present results demonstrated that a network of cells and structures were largely present in mammosphere cellular communication in vitro and in vivo. Therefore, blocking cellular communication may prove beneficial in halting the progression of mammary tumors.

Histopathologic characteristics of background parenchymal enhancement (BPE) on breast MRI

PURPOSE

Breast fibroglandular tissue (FGT), as visualized on a mammogram (mammographic density, MD), is one of the strongest known risk factors for breast cancer. FGT is also visible on breast MRI, and increased background parenchymal enhancement (BPE) in the FGT has been identified as potentially a major breast cancer risk factor. The aim of this exploratory study was to examine the biologic basis of BPE.

METHODS

We examined the unaffected contra-lateral breast of 80 breast cancer patients undergoing a prophylactic mastectomy before any treatment other than surgery of their breast cancer. BPE was classified on the BI-RADS scale (minimal/mild/moderate/marked). Slides were stained for microvessel density (MVD), CD34 (another measure of endothelial density), glandular tissue within the FGT and VEGF. Spearman correlations were used to evaluate the associations between BPE and these pathologic variables.

RESULTS

In pre-menopausal patients, BPE was highly correlated with MVD, CD34 and glandular concentration within the FGT, and the pathologic variables were themselves highly correlated. The expression of VEGF was effectively confined to terminal duct lobular unit (TDLU) epithelium. The same relationships of the four pathologic variables with BPE were seen in post-menopausal patients, but the relationships were much weaker and not statistically significant.

CONCLUSION

The strong correlation of BPE and MVD together with the high correlation of MVD with glandular concentration seen in pre-menopausal patients indicates that increased breast cancer risk associated with BPE in pre-menopausal women is likely to result from its association with increased concentration of glandular tissue in the FGT. The effective confinement of VEGF expression to the TDLUs shows that the signal for MVD growth arises directly from the glandular tissue. Further studies are needed to understand the basis of BPE in post-menopausal women.

CD24 Expression and differential resistance to chemotherapy in triple-negative breast cancer

Breast cancer (BC) is a leading cause of cancer-related death in women. Adjuvant systemic chemotherapies are effective in reducing risks of recurrence and have contributed to reduced BC mortality. Although targeted adjuvant treatments determined by biomarkers for endocrine and HER2-directed therapies are largely successful, predicting clinical benefit from chemotherapy is more challenging. Drug resistance is a major reason for treatment failures. Efforts are ongoing to find biomarkers to select patients most likely to benefit from chemotherapy. Importantly, cell surface biomarkers CD44+/CD24- are linked to drug resistance in some reports, yet underlying mechanisms are largely unknown. This study focused on the potential role of CD24 expression in resistance to either docetaxel or doxorubicin in part by the use of triple-negative BC (TNBC) tissue microarrays. In vitro assays were also done to assess changes in CD24 expression and differential drug susceptibility after chemotherapy. Further, mouse tumor xenograft studies were done to confirm in vitro findings. Overall, the results show that patients with CD24-positive TNBC had significantly worse overall survival and disease-free survival after taxane-based treatment. Also, in vitro cell studies show that CD44+/CD24+/high cells are more resistant to docetaxel, while CD44+/CD24-/low cells are resistant to doxorubicin. Both in vitro and in vivo studies show that cells with CD24-knockdown are more sensitive to docetaxel, while CD24-overexpressing cells are more sensitive to doxorubicin. Further, mechanistic studies indicate that Bcl-2 and TGF-βR1 signaling via ATM-NDRG2 pathways regulate CD24. Hence, CD24 may be a biomarker to select chemotherapeutics and a target to overcome TNBC drug resistance.

5-Fluorouracil may enrich cancer stem cells in canine mammary tumor cells in vitro

Mammary gland carcinomas are the most common neoplasms in women and unsterilized female dogs. Owing to the existence of cancer stem cells (CSCs), chemotherapy is not able to cure these types of diseases completely. A number of studies have demonstrated that CSCs are resistant to chemotherapeutic drugs, but whether canine mammary tumor cells that have acquired resistance to 5-fluorouracil (5-FU) exhibited properties of CSCs remains unknown. The aim of the present study was to investigate whether 5-fluorouracil-resistant canine mammary tumor cells exhibited properties of CSCs. CSCs were analyzed using western blot assays, ultra-low attachment sphere cultures, flow cytometry and migration (wound healing and Transwell) assays. The results indicated that, compared with parental cells, proteins associated with the Wnt/β-catenin signaling pathway and aldehyde dehydrogenase 1 were overexpressed, the number and size of spheres in the 5-FU-resistant cells were increased, the ratio of CD44⁺/CD24^-/low cells was increased and the migratory ability was improved in vitro compared with the 5-FU-susceptible cells. In conclusion, stimulation with chemotherapeutic drugs including 5-FU is a good method for increasing the proportion of canine mammary tumor stem cells in vitro, which may provide further understanding of chemotherapeutic methods and CSCs.

Metformin and melatonin inhibit DMBA-induced mammary tumorigenesis in rats fed a high-fat diet

The data from in-vitro and in-vivo studies show that both peroral antidiabetic metformin (MF) and pineal hormone melatonin (MT) inhibit the growth of many cancers, including breast cancer. However, most in-vivo studies used standard-type diet with low fat content. Therefore, in this study, we evaluated the chemopreventive effect of MF and MT in an in-vivo model of breast cancer in rats on a high-fat diet (10% of total fat). Mammary carcinogenesis was induced by 7,12-dimethylbenz[a]anthracene (DMBA) in female Sprague-Dawley rats. Chemoprevention with MF (administered in a diet, 0.2%) and MT (administered in tap water, 20 mg/l) was induced 20 days before the carcinogen administration through the termination of the experiment (14 weeks after carcinogen administration). Tumor growth parameters were analyzed together with histopathological examination and immunohistochemical detection of KI67 (proliferation marker), caspase-3, BAX, BCL-2 (apoptosis markers), and CD24 and CD44 (cancer stem cell markers) in mammary tumor samples. The combination of chemopreventive agents decreased tumor incidence by 29%. Cumulative tumor volume was lower in all groups treated with chemoprevention. Histopathology did not show significant changes in high-grade/low-grade tumor ratio. Immunohistochemistry showed increased expression of BAX in the combination group, and caspase-3 expression increased in both MT and combination groups. MT, and particularly the MF and MT combination, inhibited DMBA-induced mammary tumor growth in rats by apoptosis stimulation in cancer cells. Our results indicate that MT supplements in patients treated with MF may have a considerable effect on the incidence of breast cancer.

The Biological Activities of Sesterterpenoid-Type Ophiobolins

Ophiobolins (Ophs) are a group of tricarbocyclic sesterterpenoids whose structures contain a tricyclic 5-8-5 carbotricyclic skeleton. Thus far, 49 natural Ophs have been reported and assigned into A-W subgroups in order of discovery. While these sesterterpenoids were first characterized as highly effective phytotoxins, later investigations demonstrated that they display a broad spectrum of biological and pharmacological characteristics such as phytotoxic, antimicrobial, nematocidal, cytotoxic, anti-influenza and inflammation-promoting activities. These bioactive molecules are promising drug candidates due to the developments of their anti-proliferative activities against a vast number of cancer cell lines, multidrug resistance (MDR) cells and cancer stem cells (CSCs). Despite numerous studies on the biological functions of Ophs, their pharmacological mechanism still requires further research. This review summarizes the chemical structures, sources, and biological activities of the oph family and discusses its mechanisms and structure-activity relationship to lay the foundation for the future developments and applications of these promising molecules.

Age-associated prognostic and predictive biomarkers in patients with breast cancer

To date, no comprehensive prognostic or predictive marker profiling analysis has been performed in association with the age of patients with breast cancer. In the present study, 632 breast cancer tissue samples were analyzed for expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), B-cell lymphoma (Bcl)-2 protein, HER2 gene amplification, proliferation [as evaluated by proliferating cell nuclear antigen (PCNA) and Ki-67 index], tumor grade, histological type and molecular subtype. The data revealed correlations with the age of patients. A statistically significant positive correlation was identified between patient age and expression of ER (P<0.0001). There was no significant association between patient age and PR, HER2 protein expression, HER2 gene amplification or PCNA. A significant negative correlation between age and Ki-67 expression (P<0.0001) as well as grade of tumor (P=0.007) was identified. The spectrum of molecular subtypes differed according to age (P=0.0003). The highest incidence of aggressive triple-negative and HER2-positive breast cancer was present in patients aged between 20 and 39 years. Luminal A subtype was the most frequent cancer subtype in patients from age 40 onwards, where proliferation activity declined with age and expression of hormone receptors increased along with Bcl-2 expression. Aggressive forms of breast cancer were more common in younger patients. Prognostic and predictive markers have a complex age-specific distribution. The findings of less aggressive luminal A and B subtypes in older patients, and the positive correlation with ER, PR and Bcl-2 expression reveal the potential efficacy of Bcl-2 as a marker of hormone responsiveness in these patients.

The Anti-Cancer Effect of Polyphenols against Breast Cancer and Cancer Stem Cells: Molecular Mechanisms

The high incidence of breast cancer in developed and developing countries, and its correlation to cancer-related deaths, has prompted concerned scientists to discover novel alternatives to deal with this challenge. In this review, we will provide a brief overview of polyphenol structures and classifications, as well as on the carcinogenic process. The biology of breast cancer cells will also be discussed. The molecular mechanisms involved in the anti-cancer activities of numerous polyphenols, against a wide range of breast cancer cells, in vitro and in vivo, will be explained in detail. The interplay between autophagy and apoptosis in the anti-cancer activity of polyphenols will also be highlighted. In addition, the potential of polyphenols to target cancer stem cells (CSCs) via various mechanisms will be explained. Recently, the use of natural products as chemotherapeutics and chemopreventive drugs to overcome the side effects and resistance that arise from using chemical-based agents has garnered the attention of the scientific community. Polyphenol research is considered a promising field in the treatment and prevention of breast cancer.

Effect of surgical wound fluids after intraoperative electron radiotherapy on the cancer stem cell phenotype in a panel of human breast cancer cell lines

The wound healing process after surgery alters the area surrounding the original tumor and around the scar, and the modified microenvironment is more favorable for tumor recurrence. Intraoperative radiotherapy (IORT) is one of the more novel strategies in breast cancer (BC) treatment. Irradiation during surgery has effects on the tumor microenvironment, abrogating the proliferative cascade induced by surgical wound healing. The aim of the present study was to determine the effect of surgical wound fluids from IOERT treatment (RT-WF) compared with wound fluids from conservative-breast surgery only (WF) on the cancer stem cell phenotype in a panel of BC cell lines. Post-operative wound fluids were derived from patients with BC who underwent a tumor resection (quadrantectomy) plus intraoperative electron radiotherapy using a single dose of ≤10 Gy on the tumor bed and surrounding tissues, or from those who underwent a tumor resection without IOERT. Cell lines were incubated with 10% wound fluids, and after 4 days, the cluster of differentiation (CD)44⁺/CD24^-/low phenotype and aldehyde dehydrogenase 1 (ALDH1) activity were determined by flow cytometry. The two types of fluid each affected the CD44⁺/CD24^-/low phenotype. The results varied markedly between each cell line, even for the same histological subtypes. RT-WF decreased the CD44⁺/CD24^-/low populations in the basal-like BT-549 and MDA-MB-468 cell lines, whereas in the luminal type MCF7 cell line, the two fluids inhibited these populations. The HER-OE subtypes harbored a minimal CD44⁺/CD24^-/low population, but the growth of SK-BR-3 was stimulated by the two post-operative fluids. WF exhibited a stronger effect on ALDH1 activity compared with RT-WF. The stimulatory effect was dependent on the histological subtype of the cell line and the strongest dependence was observed in luminal subtypes characterized by low dehydrogenase activity in the control group. The present results enable a better understanding of the mechanism of recurrence and metastases following BC surgery. With respect to histological phenotype, its effect on tumor progression, either local or systemic, strongly suggests the requirement for further research and clinical validation.

Potential biomarker panels in overall breast cancer management: advancements by multilevel diagnostics

Breast cancer (BC) prevalence has reached an epidemic scale with half a million deaths annually. Current deficits in BC management include predictive and preventive approaches, optimized screening programs, individualized patient profiling, highly sensitive detection technologies for more precise diagnostics and therapy monitoring, individualized prediction and effective treatment of BC metastatic disease. To advance BC management, paradigm shift from delayed to predictive, preventive and personalized medical services is essential. Corresponding step forwards requires innovative multilevel diagnostics procuring specific panels of validated biomarkers. Here, we discuss current instrumental advancements including genomics, proteomics, epigenetics, miRNA, metabolomics, circulating tumor cells and cancer stem cells with a focus on biomarker discovery and multilevel diagnostic panels. A list of the recommended biomarker candidates is provided.

Phosphorylated-p38 mitogen-activated protein kinase expression is associated with clinical factors in invasive breast cancer

Purpose

P38 mitogen-activated protein kinases (MAPK) level is an important prognostic factor in breast cancer. This study was performed to detect the expressions of P-p38 MAPK expression in breast cancer and explore their correlations with clinicopathological factors.

Experimental design

Tumor samples from 355 Chinese patients diagnosed with invasive breast cancer and adjacent non-cancerous tissue were collected between 2003 and 2010. The expression of P-p38 MAPK was analyzed using immunohistochemical staining. The correlations between P-p38 MAPK expression and clinicopathological findings including age, AJCC Stage, Histologic characters, ER, PR, and HER2 were analyzed using the parametric correlation method. P-p38 MAPK was selected as dependent variable to perform multivariate analysis respectively at last.

Results

Overall, 161 (45 %) and 183 (52 %) of the 355 specimens showed positive P-p38 MAPK staining in the cytoplasm and nucleus respectively, which were significant higher than that in the adjacent non-cancerous tissues in both the cytoplasm and the nucleus. High P-p38 MAPK expression of cytoplasm and nucleus were both associated with positive PR status in luminal A/B type of breast cancer, and were both associated with positive HER2 status in HER2-positive type of breast cancer. The result of multivariate analysis demonstrated that HER2 and PR were both significantly association with P-p38 MAPK expression of cytoplasm and nucleus.

Conclusions

Our study suggests that P-p38 MAPK expression were significantly associated with clinicopathological factors and PR/HER2 might association with phosphorylation of p38 MAPK in different types of breast cancer.

Breast cancer stem-like cells: clinical implications and therapeutic strategies

Breast cancer is the most frequently diagnosed cancer in women, being also the leading cause of cancer death among female population, including in Romania. Resistance to therapy represents a major problem for cancer treatment. Current cancer treatments are both expensive and induce serious side effects; therefore ineffective therapies are both traumatic and pricy. Characterizing predictive markers that can identify high-risk patients could contribute to dedicated/personalized therapy to improve the life quality and expectancy of cancer patients. Moreover, there are some markers that govern specific tumor molecular features that can be targeted with specific therapies for those patients who are most likely to benefit. The identification of stem cells in both normal and malignant breast tissue have lead to the hypothesis that breast tumors arise from breast cancer stem-like cells (CSCs), and that these cells influence tumor’s response to therapy. CSCs have similar self-renewal properties to normal stem cells, however the balance between the signaling pathways is altered towards tumor formation In this review, we discuss the molecular aspects of breast CSCs and the controversies regarding their use in the diagnosis and treatment decision of breast cancer patients.

Role of a polyphenol-enriched preparation on chemoprevention of mammary carcinoma through cancer stem cells and inflammatory pathways modulation

BACKGROUND

Naturally occurring polyphenolic compounds from fruits, particularly from blueberries, have been reported to be significantly involved in cancer chemoprevention and chemotherapy. Biotransformation of blueberry juice by Serratia vaccinii increases its polyphenolic content and endows it with anti-inflammatory properties.

METHODS

This study evaluated the effect of a polyphenol-enriched blueberry preparation (PEBP) and its non-fermented counterpart (NBJ), on mammary cancer stem cell (CSC) development in in vitro, in vivo and ex vivo settings. Effects of PEBP on cell proliferation, mobility, invasion, and mammosphere formation were measured in vitro in three cell lines: murine 4T1 and human MCF7 and MDA-MB-231. Ex vivo mammosphere formation, tumor growth and metastasis observations were carried out in a BALB/c mouse model.

RESULTS

Our research revealed that PEBP influence cellular signaling cascades of breast CSCs, regulating the activity of transcription factors and, consequently, inhibiting tumor growth in vivo by decreasing metastasis and controlling PI3K/AKT, MAPK/ERK, and STAT3 pathways, central nodes in CSC inflammatory signaling. PEBP significantly inhibited cell proliferation of 4T1, MCF-7 and MDA-MB-231. In all cell lines, PEBP reduced mammosphere formation, cell mobility and cell migration. In vivo, PEBP significantly reduced tumor development, inhibited the formation of ex vivo mammospheres, and significantly reduced lung metastasis.

CONCLUSIONS

This study showed that polyphenol enrichment of a blueberry preparation by fermentation increases its chemopreventive potential by protecting mice against tumor development, inhibiting the formation of cancer stem cells and reducing lung metastasis. Thus, PEBP may represent a novel complementary alternative medicine therapy and a source for novel therapeutic agents against breast cancer.

Tumor Microenvironment Versus Cancer Stem Cells in Cholangiocarcinoma: Synergistic Effects?

Cholangiocarcinoma (CCAs) may be defined as tumors that derived from the biliary tree with the differentiation in the biliary epithelial cells. This tumor is malignant, extremely aggressive with a poor prognosis. It can be treated surgically and its pathogenesis is poorly understood. The tumor microenvironment (TME) is a very important factor in the regulation of tumor angiogenesis, invasion, and metastasis. Besides cancer stem cells (CSCs) can modulate tumor growth, stroma formation, and migratory capability. The initial stage of tumorigenesis is characterized by genetic mutations and epigenetic alterations due to intrinsic factors which lead to the generation of oncogenes thus inducing tumorigenesis. CSCs may result from precancerous stem cells, cell de-differentiation, normal stem cells, or an epithelial-mesenchymal transition (EMT). CSCs have been found in the cancer niche, and EMT may occur early within the tumor microenvironment. Previous studies have demonstrated evidence of cholangiocarcinoma stem cells (CD133, CD24, EpCAM, CD44, and others) and the presence of these markers has been associated with malignant potential. The interaction between TME and cholangiocarcinoma stem cells via signaling mediators may create an environment that accommodates tumor growth, yielding resistance to cytotoxic insults (chemotherarapeutic). While progress has been made in the understanding of the mechanisms, the interactions in the tumorigenic process still remain a major challenge. Our review, addresses recent concepts of TME-CSCs interaction and will emphasize the importance of early detection with the use of novel diagnostic mechanisms such as CCA-CSC biomarkers and the importance of tumor stroma to define new treatments. J. Cell. Physiol. 231: 768-776, 2016. © 2015 Wiley Periodicals, Inc.

Co-ordination of cell cycle, migration and stem cell-like activity in breast cancer

Migration, proliferation and stem cell-like activity are all key cellular characteristics which aid the formation and progression of breast cancer, in addition to involvement in treatment resistance. Many current therapies aim to target tumour proliferation, and although successful, mortality rates in breast cancer remain significant. Our main objectives were to investigate the relationship between proliferation, migration and stem cell-like activity in breast cancer. We used a panel of cell lines and primary human breast cancer samples to assess the relationship between migration, proliferation and stem cells. We performed live cell sorting according to cell cycle (Hoechst-33324) and in combination with stem-cell markers (CD44/CD24/ESA) followed by assessment of migration and stem cell activity (mammosphere formation). We identified an inverse relationship between proliferation and migration/stem cell-like activity. G0/1 cells showed increased migration and mammosphere formation. Furthermore we identified a subpopulation of low proliferative stem-like cells (CD44+/24lo/ESA+) with increased migration and mammosphere formation that are specifically inhibited by Dickkopf 1 (DKK1) and Dibenzazepine (DBZ) known stem-cell inhibitors. These data show the co-ordination of migration, proliferation and stem cell activity in breast cancer, and has identified a sub-population of stem-like cells, greatly adding to our understanding of the complex nature of stem cell biology.

Persistence of CD34 Stem Marker in Human Lipoma: Searching for Cancer Stem Cells

Background: Lipomas are benign solid tumours that develop in soft tissues with origin in mesenchymal progenitors. Macroscopically, they appear as soft-elastic nodules, varying in volume from a few millimiters to several centimetres and can enlarge progressively. Although they are usually asymptomatic, they can cause symptoms due to nerve or vessel compression. Microscopically they appear as fibrous connective tissue stroma with embedded adipocytes, and absence of inflammation. Up to now no characterisation of stem cell population present in this tissue has been performed.

Methods: Cytofluorimetric, biological and molecular biology analyses have been performed in order to test superficial cell markers and gene expression profile related to stemness and apoptotic activity of cells present in lipoma tissues compared to those of adipose tissue's cells.

Results: Our results confirmed that CD34⁺ cells in lipoma were present around small adipocytes, showing several altered biological activity such as proliferation, apoptotis and stemness.

Conclusions: The data emerging from the comparison of the lipoma cells and normal adipose tissue, suggests the presence of cell precursors involved in the development of the lipoma. This hypothesis requires further investigation and may indicate new thresholds in the study of benign tumour pathogenesis.

Monocytes and macrophages, implications for breast cancer migration and stem cell-like activity and treatment

Macrophages are a major cellular constituent of the tumour stroma and contribute to breast cancer prognosis. The precise role and treatment strategies to target macrophages remain elusive. As macrophage infiltration is associated with poor prognosis and high grade tumours we used the THP-1 cell line to model monocyte-macrophage differentiation in co-culture with four breast cancer cell lines (MCF7, T47D, MDA-MB-231, MDA-MB-468) to model in vivo cellular interactions. Polarisation into M1 and M2 subtypes was confirmed by specific cell marker expression of ROS and HLA-DR, respectively. Co-culture with all types of macrophage increased migration of ER-positive breast cancer cell lines, while M2-macrophages increased mammosphere formation, compared to M1-macrophages, in all breast cancer cells lines. Treatment of cells with Zoledronate in co-culture reduced the "pro-tumourigenic" effects (increased mammospheres/migration) exerted by macrophages. Direct treatment of breast cancer cells in homotypic culture was unable to reduce migration or mammosphere formation.Macrophages promote "pro-tumourigenic" cellular characteristics of breast cancer cell migration and stem cell activity. Zoledronate targets macrophages within the microenvironment which in turn, reduces the "pro-tumourigenic" characteristics of breast cancer cells. Zoledronate offers an exciting new treatment strategy for both primary and metastatic breast cancer.

The clinicopathological and prognostic significance of CD24, CD44, CD133, ALDH1 expressions in invasive ductal carcinoma of the breast: CD44/CD24 expression in breast cancer

BACKGROUND

Recently, there are several studies about cancer stem cells (CSC), indicating that they are the cells that initiate the tumor, provide progression, metastasis and responsible for the aggressive tumor behavior.

MATERIALS AND METHODS

The purpose of this study is to investigate the expressions of CD24, CD44, their different combinations, ALDH1 and CD133 in invasive ductal carcinoma. Their relationships with clinicopathologic parameters, such as tumor grade, lymphovascular invasion, tumor size, axillary lymph node involvement, stage, hormone receptors, HER2 expression, basal like tumors, triple negative status and prognosis were also investigated. Tissue microarray method was used to investigate ımmunohistochemical CD24, CD44, ALDH1 and CD133 expressions in 105 invasive ductal carcinoma cases.

RESULTS

CD133 expression was significantly associated with tumor size (p=0.023) and stage (p=0.009). CD133 expression was decreased in tumors with larger tumor size, higher stage and lymphovascular invasion. CD133 expression was positively correlated with CD44 (r=0.212, p=0.032) and CD44(+)/CD24(+) (r=0.202, p=0.040) expressions. CD44, CD24 and ALDH1 expressions showed no significant relationship and correlation with clinicopathologic features. There was a significant relationship (p=0.048) between CD44(+)/CD24(-/low) phenotype and basal like tumors. EGFR expression was positively correlated with CD44(+)/CD24(-/low) phenotype (r=0.211, p=0.036).

CONCLUSIONS

Basal like tumors are enriched for CSCs with CD44(+)/CD24(-/low) phenotype. CD133 can detect a different population of CSC in breast carcinoma.

Expression of cancer stem cell biomarkers as a tool for a correct therapeutic approach to hepatocellular carcinoma

Liver cancer is the fifth most commonly diagnosed malignancy and the second most frequent cause of cancer death in men worldwide. Amongst liver cancers, hepatocellular carcinoma (HCC) represents the major histological subtype and it is one of the most common malignant human tumors worldwide. Research into the molecular biology of hepatocarcinogenesis has identified several biomarkers, which could provide additional informations in order to better understand the biology of HCC. A large number of biomarkers have been shown to have potential predictive significance and a wide variety of molecular markers have been proven to be excellent diagnostic tools for HCC but it is difficult to characterize HCC with a single biomarker. Thus, signatures of a combination of biomarkers may be more valuable for the diagnosis, staging and prognosis of HCC. Specifically, a correlation of HCC-CSCs phenotype to specific hepatic cancer subtypes and to specific clinical and pathological features has not yet been reported in human liver tumors. In this view we will first discuss the possible sources of liver stem cells and their relation with liver cancer development and we will secondly focus on the prognostic significance of clinical and pathological features of HCC.

Clinicopathological significance of CD133 and CD44 expression in infiltrating ductal carcinoma and their relationship to angiogenesis

BACKGROUND

Breast cancer is the leading cause of cancer death in females worldwide, and the majority type is infiltrating ductal carcinoma (IDC). Most of IDC patients died of metastasis and recurrence. Cancer stem cells (CSCs) are defined with the ability to be self-renewal and potentially promote proliferation and formation of tumors. CSCs are related to angiogenesis and are important targets in new cancer treatment strategies. In this study, we purposed to investigate on expression and clinical significances of CSCs marked by CD133 and CD44 in IDC and their relationship to angiogenesis.

METHODS

The specimens of IDC from 325 Chinese patients with follow-up were analyzed for CD133, CD44, CD82, and CD34 protein expression by immunohistochemical staining. The Pearson chi-square test and t test were used to assess the associations among the positive staining of these markers and clinicopathological characteristics. Postoperative overall survival time in these patients with IDC was analyzed by univariate and multivariate analyses.

RESULTS

In IDC tissues, positive rates of 48.6%, 53.8%, and 42.2% were obtained for CD133, CD44, and CD82 protein, respectively; the mean score of microvessel density (MVD) was 20.5 ± 7.0 in IDC group. And there was a significant difference between the two groups. There was a positive relationship between the expression of CD133, CD44, and the score of MVD and the grades of tumor, lymph node metastasis, tumor-node-metastasis (TNM) stages (all P < 0.05); and the expression of CD82 was negatively related to grades of tumor, lymph node metastasis, and TNM stages (all P < 0.05). The overall mean survival time of the patients with CD133, CD44, and the score of MVD (≥21) positive expression was lower than that of patients with negative expression. The overall mean survival time of patients of CD82-positive expression was longer than that of patients of the negative expression group. The positive expression of CD133 and CD82, and TNM stages were independent prognostic factors of IDC (P < 0.05).

CONCLUSIONS

CSCs, angiogenesis, and aberrant expression of CD82 may be involved in the initiation, development, metastasis, and recurrence. It is suggested that CSCs, angiogenesis, and CD82 be possible as a therapeutic marker for anti-tumor therapy.

Expression and significance of CD44, CD47 and c-met in ovarian clear cell carcinoma

AIMS

The aim of the present study is to investigate the differential expression of CD44, CD47 and c-met in ovarian clear cell carcinoma (OCCC), the correlation in their expression and their relationship with the biological behavior of OCCC.

METHODS

We used immunohistochemistry to examine the expression of CD44, CD47 and c-met in OCCC (86 cases) and investigated the effects of the expression and interaction of these molecules on the development of OCCC.

RESULTS

CD44, CD47 and c-met expression was significantly high in OCCC. Expression of CD44 and CD47 correlated with patient surgical stage, chemotherapy resistance and prognosis (all p<0.05), and expression of c-met correlated with chemotherapy resistance and prognosis (all p<0.05), but did not correlate with lymph node metastasis (all p>0.05). The surgical stage, CD44, CD47 and c-met expression were independent risk factors for OCCC prognosis (all p<0.05). Patients with low levels of CD44, CD47 and c-met showed better survival than those with high levels (all p<0.05). There was a positive correlation between CD44 (or CD47) and c-met, as well as between CD44 and CD47 (the Spearman correlation coefficient rs was 0.783, 0.776 and 0.835, respectively, all p<0.01). Additionally, pairwise correlation analysis of these three markers shows that the high expression of CD44/CD47, CD44/c-met and CD47/c-met were correlated with patient surgical stage, chemotherapy resistance and prognosis (all p<0.05), but did not correlate with lymph node metastasis (all p>0.05).

CONCLUSIONS

Expression of CD44, CD47 and c-met was upregulated in OCCC and pairwise correlation. CD44, CD47 and c-met may have synergistic effects on the development of OCCC and are prognostic factors for ovarian cancer.