Traditional medicine herbs as natural product matrices in cancer chemoprevention: A trans pharmacological perspective (scoping review)

Emerging evidence on molecular biology related to tumors, inflammation, and immunity, highlights their architectural commonality shifting cancer treatment paradigms toward more economical prevention than treatment. Statistical surveys reveal exponentially growing herbal drug supplementation in cancer worldwide as vast pre-clinical and clinical data unravel their multi-mechanistic pharmacology. The integrative oncological approach calls for more "holistic" principles to be amalgamated into cancer care. New cancer drug development from herbs need not be limited by the archetypal 'RCT-Standardization' bottlenecks. Based on comprehensive literature scoping as per Prisma-ScR guidelines, we herein concurrently reviewed evidence-based research reports of selected Indian Traditional Medicine (ITM) herbs of anticancer repute in parallel with their holistic therapeutics; a rationalistic exploration of ITM's scientific genre. Their synergy effect on cancer revisited using a trans-pharmacological approach validates ITM's seemingly simplistic health/disease equation model, showing a fresh new avenue for re-purposing whole herbal drug complexes in cancer management. Herbal drugs as per ITM are natural matrices whose dynamics of interaction in the etiopathology of cancer are conceptually and mechanistically integrative. Lateral perspective to the same as laid out in this review holds the key to their effectual development as more tangible cancer chemopreventives/new drug targets/leads if not as new pharmacological tools.

Role of histone acetyltransferase inhibitors in cancer therapy

The development of cancer is a complex phenomenon driven by various extrinsic as well as intrinsic risk factors including epigenetic modifications. These post-translational modifications are encountered in diverse cancer cells and appear for a relatively short span of time. These changes can significantly affect various oncogenic genes and proteins involved in cancer initiation and progression. Histone lysine acetylation and deacetylation processes are controlled by two opposing classes of enzymes that modulate gene regulation either by adding an acetyl moiety on a histone lysine residue by histone lysine acetyltransferases (KATs) or via removing it by histone deacetylases (KDACs). Deregulated KAT activity has been implicated in the development of several diseases including cancer and can be targeted for the development of anti-neoplastic drugs. Here, we describe the predominant epigenetic changes that can affect key KAT superfamily members during carcinogenesis and briefly highlight the pharmacological potential of employing lysine acetyltransferase inhibitors (KATi) for cancer therapy.

The expanding roles of long non-coding RNAs in the regulation of cancer stem cells

Long non-coding RNAs (lncRNAs) are a novel class of gene regulators playing multifaceted roles in physiological processes as well as pathological conditions such as cancer. Cancer stem cells (CSCs) are a small subset of tumor cells that constitute the origin and development of various malignant tumors. CSCs have been identified in a wide spectrum of human tumors and could act as a critical link underlying the processes of tumor metastasis and recurrence. Mounting evidence indicates that lncRNAs are aberrantly expressed in diverse CSCs and regulate CSC properties at different molecular levels. Here, we very briefly summarize the recent findings on the potential roles of lncRNAs in regulating various functions of CSCs, and elaborate on how can lncRNAs impact CSC properties via interacting with other macromolecules at the epigenetic, transcriptional, and post-transcriptional levels. This mini-review also highlights the understanding of the modular regulatory principles of lncRNA interactions in CSCs.

Targeting multiple oncogenic pathways for the treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common forms of liver cancer diagnosed worldwide. HCC occurs due to chronic liver disease and is often diagnosed at advanced stages. Chemotherapeutic agents such as doxorubicin are currently used as first-line agents for HCC therapy, but these are non-selective cytotoxic molecules with significant side effects. Sorafenib, a multi-targeted tyrosine kinase inhibitor, is the only approved targeted drug for HCC patients. However, due to adverse side effects and limited efficacy, there is a need for the identification of novel pharmacological drugs beyond sorafenib. Several agents that target and inhibit various signaling pathways involved in HCC are currently being assessed for HCC treatment. In the present review article, we summarize the diverse signal transduction pathways responsible for initiation as well as progression of HCC and also the potential anticancer effects of selected targeted therapies that can be employed for HCC therapy.

A novel benzimidazole derivative, MBIC inhibits tumor growth and promotes apoptosis via activation of ROS-dependent JNK signaling pathway in hepatocellular carcinoma

A prior screening programme carried out using MTT assay by our group identified a series of novel benzimidazole derivatives, among which Methyl 2-(5-fluoro-2-hydroxyphenyl)-1H- benzo[d]imidazole-5-carboxylate (MBIC) showed highest anticancer efficacy compared to that of chemotherapeutic agent, cisplatin. In the present study, we found that MBIC inhibited cell viability in different hepatocellular carcinoma (HCC) cell lines without exerting significant cytotoxic effects on normal liver cells. Annexin V-FITC/PI flow cytometry analysis and Western blotting results indicated that MBIC can induce apoptosis in HCC cells, which was found to be mediated through mitochondria associated proteins ultimately leading to the activation of caspase-3. The exposure to MBIC also resulted in remarkable impairment of HCC cell migration and invasion. In addition, treatment with MBIC led to a rapid generation of reactive oxygen species (ROS) and substantial activation of c-Jun-N-terminal kinase (JNK). The depletion of ROS by N-Acetyl cysteine (NAC) partially blocked MBIC-induced apoptosis and JNK activation in HCC cells. Finally, MBIC significantly inhibited tumor growth at a dose of 25 mg/kg in an orthotopic HCC mouse model. Taken together, these results demonstrate that MBIC may inhibit cell proliferation via ROS-mediated activation of the JNK signaling cascade in HCC cells.

Abstract 932: Wnt antagonist, secreted frizzled-related protein 4 (SFRP4) and peptides from its associated domains, increases chemotherapeutic response of cancer stem cells of malignant mesothelioma cell lines

Malignant mesothelioma (MM) is a highly aggressive cancer associated with past asbestos exposure that is characterized by rapid progression, late metastases and poor prognosis. There is a need for much improved and novel therapies for this cancer through improved biological understanding of the disease.Previous studies have shown that SFRPs in general and SFRP4 in particular are down regulated in mesothelioma tissue and cell lines 1-4. Based on our own study and previously demonstrated a role for sFRP4 in making chemoresistant tumours amenable to chemotherapeutics 5-16. We have now progressed our work into the effects of peptides derived from the cysteine-rich domain and the netrin-like domain of sFRP4 on tumour initiating cells derived from MM cell lines.We examined the effect of secreted frizzled-related protein 4 (sFRP4), a Wnt signaling antagonist and its associated peptides, in chemosensitizing the MM cell line ONE 58 and JU77 and MM cancer stem cells (CSCs) enriched from these two cell lines to chemotherapeutics.We found tumorspheres exposed to sFRP4 and peptides alone and in combination with cisplatin induced cell death and decreased CD133 and ALDH1 expression.We thus identified for the first time that sFRP4 and associated peptides could help to sensitise to chemotherapeutics and destroy cancer stem cells of MM cell line, which would lead to effective treatment regimen to combat malignant mesothelioma. Our initial in vitro data exemplify the ability of these peptides in diminishing the numbers of therapy-resistant Tumor initiating cells (TICs).

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Citation Format: Vanathi Perumal, Senthil Kumar, Frank Arfuso, Simon Fox, Arunasalam Dharmarajan. Wnt antagonist, secreted frizzled-related protein 4 (SFRP4) and peptides from its associated domains, increases chemotherapeutic response of cancer stem cells of malignant mesothelioma cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 932. doi:10.1158/1538-7445.AM2017-932

Inhibition of p300 lysine acetyltransferase activity by luteolin reduces tumor growth in head and neck squamous cell carcinoma (HNSCC) xenograft mouse model

Chromatin acetylation is attributed with distinct functional relevance with respect to gene expression in normal and diseased conditions thereby leading to a topical interest in the concept of epigenetic modulators and therapy. We report here the identification and characterization of the acetylation inhibitory potential of an important dietary flavonoid, luteolin. Luteolin was found to inhibit p300 acetyltransferase with competitive binding to the acetyl CoA binding site. Luteolin treatment in a xenografted tumor model of head and neck squamous cell carcinoma (HNSCC), led to a dramatic reduction in tumor growth within 4 weeks corresponding to a decrease in histone acetylation. Cells treated with luteolin exhibit cell cycle arrest and decreased cell migration. Luteolin treatment led to an alteration in gene expression and miRNA profile including up-regulation of p53 induced miR-195/215, let7C; potentially translating into a tumor suppressor function. It also led to down-regulation of oncomiRNAs such as miR-135a, thereby reflecting global changes in the microRNA network. Furthermore, a direct correlation between the inhibition of histone acetylation and gene expression was established using chromatin immunoprecipitation on promoters of differentially expressed genes. A network of dysregulated genes and miRNAs was mapped along with the gene ontology categories, and the effects of luteolin were observed to be potentially at multiple levels: at the level of gene expression, miRNA expression and miRNA processing.

Abstract 4629: The influence of adipose tissue-derived mesenchymal stem cell environment and WNT antagonism on breast tumour cells

Breast cancer is the most commonly diagnosed cancer in Australian women, with an average of 1 in 8 women being affected. Emerging evidence suggests that a close relationship exists between a tumor and the adjacent non-tumor tissue, which considerably affects the overall progression of the disease. Amongst the non-tumor cells, mesenchymal stem cells (MSCs), known to be essential for tissue and organ health, are potentially important in this regard. In our study, we focussed on the interaction between adipose tissue-derived MSCs (ADSCs) and breast tumor cells. Considering the clinical relevance of these interactions, it is imperative to understand the exact mechanisms underlying such cellular crosstalk. Here, we investigated the influence of ADSCs on breast tumor cell lines MDA MB 231 and MCF7 by using both conditioned media and extracellular matrix derived from ADSCs. We observed that the ADSC-conditioned media (ADSC-CM), harvested at specific time-points, inhibited the proliferation of tumor cells as well as their associated cancer stem cells. Further, by using molecular fractionation techniques on ADSC-CM, we identified that the <30KDa fraction of ADSC-CM retained the potential for inhibiting proliferation. We also observed decreased migration of tumor cells when treated with ADSC-CM. Further, we observed an inhibition in proliferation rates of tumor cells when treated with ADSC-deposited extracellular matrix (ADSC-ECM). Since Wnt signaling is an important pathway driving both breast tumor growth and influencing ADSC behaviour, we examined the effect of the Wnt antagonist- secreted frizzled-related protein 4 (sFRP4) and its associated peptides on tumor cells. When tumor cells were treated with sFRP4 or its peptides along with ADSC-CM/ADSC-ECM, we observed an additive inhibitory effect on tumor cell proliferation. We further observed an increase in caspase-dependent apoptosis in tumor cells following treatment with ADSC-CM and in combination with the Wnt antagonists. The effect contributed by the ADSC environment and Wnt antagonists differed in mechanism, based on the tumor cell characteristics. We can conclude that the interaction of ADSCs with tumor cells had a significant impact on tumor cell growth in terms of decreasing proliferation and migration, while increasing the rate of apoptosis, which was further elevated in the presence of Wnt antagonists. This study sheds light on novel therapeutic approaches that could be considered while devising novel anti-cancer strategies.

Citation Format: Malini Visweswaran, Frank Arfuso, Rodney Dilley, Philip Newsholme, Arunasalam Dharmarajan. The influence of adipose tissue-derived mesenchymal stem cell environment and WNT antagonism on breast tumour cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4629.

A synthetic formulation, Dhanwantharam kashaya, delays senescence in stem cells

OBJECTIVES

Mesenchymal stem cells (MSCs) derived from post-natal tissues offer a suitable source of MSCs for cellular therapy. Limitation of the use of MSCs for therapeutic purposes is attributed to the onset of senescence and slowing down of proliferation upon repeated passaging. Dhanwantram kashaya (DK), a synthetic herbal formulation, is widely used in Ayurvedic medicine as a growth stimulant in children and for nerve regeneration. In this study, we evaluated the effects of DK on the proliferation, viability and senescence of human Wharton jelly MSCs (WJMSCs) in vitro.

RESULTS

Using the MTT proliferation assay and live/dead trypan blue analysis, we found that DK increased proliferation of WJMSCS up to three folds when supplemented in the culture media. The BrdU cell proliferation assay showed a substantial increase in WJMSCs treated with DK. Notably, the β-galactosidase senescence assay revealed that drug treated WJMSCs at late passage still had intact and viable WJMSCs whereas the untreated cells exhibited profound senescence.

CONCLUSION

These studies indicate that DK enhances the quality of WJMSCs by not only increasing the proliferation rate and decreasing their turnover time but also by delaying senescence. We have, thus, identified for the first time that a traditional Ayurvedic formulation, Dhanwantram kashaya, used as a growth enhancer, is able to improve the yield and quality of stem cells in vitro and could be an effective non-toxic supplement for culturing WJMSCs for clinical applications.

Ceramide biosynthesis and metabolism in trophoblast syncytialization

Sphingolipid mediators such as ceramide are pleiotropic regulators of cellular growth, differentiation and apoptosis. We investigated the role of ceramide biosynthesis, metabolism and actions in term human cytotrophoblasts syncytialized over 7 days in culture. Intracellular C16 ceramide levels increased modestly after 3 days in culture, then declined. Ceramidase was present at particularly high levels in syncytialized trophoblasts; inhibition of ceramidase reduced the degree of cell fusion. Exposure to short chain C8 ceramide or aSMase enhanced secretion of the differentiation marker hCG without affecting fusion or cell viability. In contrast, pharmacological inhibition of ceramidase reduced the extent of fusion. Inhibition of the ceramide-responsive JNK and PP2A pathways did not abolish the effects of ceramide, and JNK phosphorylation was unresponsive to ceramide; however, ceramide significantly inhibited phosphorylation of Akt. This study suggests that changes in ceramide biosynthesis and metabolism play a differential role in the biochemical and morphological features of trophoblast differentiation.

Secreted frizzled-related protein 4 expression is positively associated with responsiveness to cisplatin of ovarian cancer cell lines in vitro and with lower tumour grade in mucinous ovarian cancers

Background

Ovarian cancer is one of the most lethal malignancies in women, as it is frequently detected at an advanced stage, and cancers often become refractory to chemotherapy. Evidence suggests that dysregulation of pro-apoptotic genes plays a key role in the onset of chemoresistance. The secreted Frizzled-Related Protein (sFRP) family is pro-apoptotic and also a negative modulator of the Wnt signalling cascade. Studies have demonstrated that the re-expression of sFRPs, in particular sFRP4, is associated with a better prognosis, and that experimentally induced expression results in cell death.

Results

In vitro experimental models determined that sFRP4 was differentially expressed in chemosensitive (A2780) and chemoresistant (A2780 ADR and A2780 Cis) ovarian cell lines, with chemosensitive cells expressing significantly higher levels of sFRP4. Transfection of the chemoresistant cell lines with sFRP4 significantly increased their sensitivity to chemotherapy. Conversely, silencing of sFRP4 expression in the chemosensitive cell line resulted in a corresponding increase in chemoresistance. Comparison of sFRP4 expression in tumour biopsies revealed a positive trend between sFRP4 expression and tumour grade, with mucinous cyst adenocarcinomas exhibiting significantly decreased sFRP4 levels compared to mucinous borderline tumours.

Conclusions

This study indicates a role for sFRP4 as a predictive marker of chemosensitivity in ovarian cancer and suggests that this pathway may be worth exploiting for novel therapies.

Sphingosine-sphingosine-1-phosphate pathway regulates trophoblast differentiation and syncytialization

Sphingosine and sphingosine-1-phosphate (S1P) are involved in regulating cell differentiation. This study postulated that changes in sphingolipid biosynthesis and metabolism are important in trophoblast syncytialization and therefore examined the production, metabolism and actions of sphingosine and S1P during spontaneous trophoblast differentiation and fusion in vitro. Significant declines in intracellular sphingosine concentration (P≤0.05) and sphingosine kinase 1 (SPHK1) expression (P≤0.01) were observed during trophoblast syncytialization. Secreted S1P concentrations dropped steeply after 72h, before rising to basal concentrations with syncytialization. Intracellular S1P concentrations were undetectable throughout. Treating cells with exogenous sphingosine (P≤0.01), S1P (P≤0.001) or a specific SPHK1 inhibitor (P≤0.05) for up to 72h in culture significantly inhibited trophoblast differentiation (measured as reduced human chorionic gonadotrophin production); effects on other biochemical and morphological markers of differentiation were absent or inconsistent. Phosphorylation of Akt, an established down-stream target of S1P that spontaneously declines with trophoblast differentiation, was markedly reduced by S1P (P≤0.05). In conclusion, changes in the sphingosine-S1P pathway are involved in the regulation of trophoblast differentiation in term human placenta. Dysregulation of sphingolipid homeostasis could, therefore, disrupt placental formation and function with deleterious consequences for pregnancy outcome.

Expression of secreted frizzled-related protein 4 (SFRP4) in primary serous ovarian tumours

OBJECTIVE

Serous ovarian cancer is the most prevalent type of ovarian cancer. The majority of women present at an advanced stage and patient survival is poor. Resistance to chemotherapy is thought to relate to failure of tumours to undergo apoptosis. Secreted frizzled-related protein 4 (SFRP4) has been demonstrated to be involved in apoptosis in the ovary but not in ovarian tumours as yet. This study examined SFRP4 expression in ovarian cancers and correlated this with expression of beta-catenin, a main component of the wNT-signalling pathway it inhibits.

METHODS

We examined 153 primary serous ovarian carcinomas for SFRP4 and B-catenin expression using immunohistochemistry on tissue microarrays and correlated this with clinical information.

RESULTS

SFRP4 expression was inversely associated with beta-catenin expression in 84% of samples. However, high-level SFRP4 expression was not significantly associated with patient survival (p = 0.08).

CONCLUSION

Elevated SFRP4 expression in serous ovarian tumours appears to correlate with reduced beta-catenin expression but long-term survival appears unaffected by this.

Caspase-14: a new player in cytotrophoblast differentiation

The human placenta is responsible for the exchange of nutrients, gas and wastes through the trophoblast maternal-fetal barrier, which is formed by the fusion of villous cytotrophoblasts to form the continuous multinucleated syncytiotrophoblast separating the maternal and fetal circulations. Caspase-14 is a seemingly non-apoptotic caspase involved in keratinocyte differentiation and cornification. It is proposed that caspase-14 has a conserved role in cellular differentiation and a role in differentiation and fusion in the trophoblast. The human choriocarcinoma BeWo cell line was treated with staurosporine and forskolin to induce apoptosis and differentiation respectively. Staurosporine initiated apoptosis within 3 h of treatment, while apoptosis was completed following 6 h treatment. Caspase-14 gene and protein expression was unchanged throughout this process. During BeWo differentiation, caspase-14 mRNA was elevated after 48 h forskolin treatment, while its protein was increased after 24 h. Therefore, caspase-14 is up-regulated during trophoblast differentiation, as represented by the BeWo cell line. Moreover, caspase-14 may interact with other signalling molecules to facilitate differentiation. This new data confirms the potential for the BeWo cell line in the functional dissection of this unusual caspase and its prospective role in trophoblast differentiation.

Quercetin Induces p53-Independent Apoptosis in Human Prostate Cancer Cells by Modulating Bcl-2-Related Proteins: A Possible Mediation by IGFBP-3

Quercetin, a flavonoid found in onion, grapes, green vegetables, etc., has been shown to possess potent antiproliferative effects against various malignant cells. We report insulin-like growth factor-binding protein-3 (IGFBP-3) as an effector of quercetin-induced apoptosis in human prostate cancer cell lines in a p53-independent manner. We evaluated the production of IGFBP-3 in quercetin-treated cells. Apoptosis was studied in quercetin-treated cells to study the IGFBP-3-mediated role with flow cytometry and DNA fragmentation. Protein expressions of Bcl-2, Bcl-x(L), and Bax were studied by Western blot. Increased production of IGFBP-3 was associated with the increased ratio of proapoptotic to antiapoptotic members of the Bcl-2 family. In quercetin-treated PC-3 cells, an increase in Bax protein expression and a decrease in Bcl-x(L) protein and Bcl-2 protein were observed. As PC-3 is a p53-negative cell line, these modulations of proapoptotic proteins and induction of apoptosis were independent of p53. The level of IGFBP-3 on the response of PC-3 cells to quercetin was examined. There was a twofold increase in IGFBP-3 level in conditioned media of 100 microM quercetin-treated cells. Quercetin also brought a peak at sub-G1 in PC-3 cells. Thus, increased level of IGFBP-3 was associated with increased proapoptotic proteins and apoptosis in response to quercetin, suggesting it may be a p53-independent effector of apoptosis in prostate cancer cells via its modulation of the Bax/Bcl-2 protein ratio.

Protein markers for Alzheimer disease in the frontal cortex and cerebellum

OBJECTIVE

To compare proteins related to Alzheimer disease (AD) in the frontal cortex and cerebellum of subjects with early-onset AD (EOAD) with or without presenilin 1 (PS1) mutations with sporadic late-onset AD (LOAD) and nondemented control subjects.

METHODS

Immunohistochemistry, immunoblot analysis, and ELISA were used to detect and assess protein levels in brain.

RESULTS

In EOAD and to a lesser extent in LOAD, there was increased amyloid beta (Abeta) deposition (by immunohistochemistry), increased soluble Abeta (by immunoblot analysis), and specific increases in Abeta40 and Abeta42 (by ELISA) in the frontal cortex and, in some cases, in the cerebellum. Surprisingly, immunoblot analysis revealed reduced levels of PS1 in many of the subjects with EOAD with or without PS1 mutations. In those PS1 mutation-bearing subjects with the highest Abeta, PS1 was barely, if at all, detectable. This decrease in PS1 was specific and not attributable solely to neuronal loss because amyloid precursor protein (APP) and the PS1-interacting protein beta-catenin levels were unchanged.

CONCLUSIONS

This study shows that in the frontal cortex and cerebellum from Alzheimer disease patients harboring certain presenilin 1 mutations, high levels of amyloid beta are associated with low levels of presenilin 1. The study provides the premise for further investigation of mechanisms underlying the downregulation of presenilin 1, which may have considerable pathogenic and therapeutic relevance.

Unusual germ cell organization in the seminiferous epithelium of a murid rodent from southern Asia, the greater bandicoot rat, Bandicota Indica

In the greater bandicoot rat, Bandicota indica, of south-east Asia, nine cell associations were documented in the testicular seminiferous epithelium. In about 10% of the tubule cross sections two or more cell associations occurred and, furthermore, some of the generations of germ cells within the cell associations were sometimes either out of phase, or missing, in the tubule cross sections. These features, together with the fact that this species has a highly pleiomorphic sperm head shape, are somewhat reminiscent of those of the seminiferous epithelium in humans and some other primates but not of common laboratory rodents. This species could thus be a good model for investigating irregular patterns of spermatogenesis in naturally occurring wild species of rodent.

003.Expression of secreted frizzled related protein-4 (sFRP-4) and associated Wnt signalling in cancer and apoptosis

We examined the interplay between Wnt and secreted frizzled related protein-4 (sFRP4) in estradiol induced cell growth in breast cancer cells (MCF-7), and also determined the in vivo distribution of sFRP-4 in human breast cancer. MCF-7 cells were treated with estradiol, sFRP-4 conditioned media and a combination of the two. Real-time RT-PCR and Western blot analysis were used to determine the expression of the sFRP-4 and its associated Wnt signalling molecules following treatment. Immunohistochemistry was performed to examine sFRP-4 expression patterns in human breast cancers. Estradiol treatment up-regulated the expression of the Wnt signalling genes Wnt-10b, beta-catenin and fz-4 (P < 0.001 for all genes). This up-regulation was not associated with an increase in the Wnt signalling pathway as measured by the levels of active beta-catenin. sFRP-4 conditioned media reduced MCF-7 cell proliferation, down-regulated the Wnt signalling genes beta-catenin and fz-4 as well as down-regulating wnt signalling activity. sFRP-4 was able to reduce the proliferation of estradiol stimulated MCF-7 cells. Cytoplasmic sFRP-4 protein was expressed in all breast tumours examined, with intense staining evident in the lobular carcinoma in situ and the ductal carcinoma. These data demonstrate that sFRP-4 is a potent inhibitor of the Wnt signalling pathway in MCF-7 cells, acting not only to down-regulate the activity of the wnt signalling pathway, but also down-regulate the transcription of Wnt signalling genes. The results of these in vitro and immunohistochemical experiments warrant further investigation as to whether sFRP-4 expression can be indicative of prognosis in human breast cancer. In addition to breast cancer, we have also examined the role of sFRP-4 in other cancers such as ovarian and prostate.

Cytogenetic analysis of embryos generated from in vitro matured mouse oocytes reveals an increase in micronuclei due to chromosome fragmentation

PURPOSE

(i) To determine the prevalence of micronuclei in the cytoplasm of embryos generated from in vitro matured oocytes. (ii) Assess whether micronuclei presence are the result of chromosome fragmentation or the loss of whole chromosomes.

METHODS

In vitro fertilization was performed on mature oocytes generated from superovulated mice (control) and in vitro matured mouse oocytes. Fertilized oocytes were cultured to the two-cell stage and fixed to slides. Micronuclei assessment was performed after staining with Giemsa. Centromere assessment was made using immunofluorescent staining (CREST) of the centromeric kinetochores.

RESULTS

Micronuclei were observed in 2% (4/197) of control two-cell embryos and 36.2% (46/127) of two-cell embryos generated from in vitro matured oocytes (P < 0.02). Centromeres were not detected in micronuclei from either group.

CONCLUSIONS

A significant increase in micronuclei was observed in embryos generated from in vitro matured oocytes. The lack of accompanyingcentromeres would suggest the micronuclei are the result of chromosome fragmentation.