Anti-tumor Activity of N4 [(E)-1-(2-hydroxyphenyl) Methylidene], N4-[(E)-2-Phenylethylidene], N4 [(E,2E)-3-Phenyl-2-propenylidene], and N4 [(E)ethylidene] Isonicotinohydrazide on K562 and Jurkat Cell Lines

Using the water eliminated mechanism, reactions of 4-pyridinecarboxylic acid hydrazide and salicylaldehyde, benzaldehyde, cinnamaldehyde, and formaldehyde afforded the corresponding N4[(E)-1-(2-hydroxyphenyl) methylidene] (NHPM), N4-[(E)-2-phenylethylidene] (NPI), N4[(E,2E)-3-phenyl-2-propenylidene] (NPPI), and N4[(E) ethylidene] (NEI) isonicotinohydrazide, in high yields, after several minutes, as reported. These new compounds have shown antitumor activity against two kinds of cancer cells, which are K562 (human chronic myeloid leukemia) and Jurkat (human T lymphocyte carcinoma)

Lack of correlation of stem cell markers in breast cancer stem cells

BACKGROUND: Various markers are used to identify the unique sub-population of breast cancer cells with stem cell properties. Whether these markers are expressed in all breast cancers, identify the same population of cells, or equate to therapeutic response is controversial. METHODS: We investigated the expression of multiple cancer stem cell markers in human breast cancer samples and cell lines in vitro and in vivo, comparing across and within samples and relating expression with growth and therapeutic response to doxorubicin, docetaxol and radiotherapy. RESULTS: CD24, CD44, ALDH and SOX2 expression, the ability to form mammospheres and side-population cells are variably present in human cancers and cell lines. Each marker identifies a unique rather than common population of cancer cells. In vivo, cells expressing these markers are not specifically localized to the presumptive stem cell niche at the tumour/stroma interface. Repeated therapy does not consistently enrich cells expressing these markers, although ER-negative cells accumulate. CONCLUSIONS: Commonly employed methods identify different cancer cell sub-populations with no consistent therapeutic implications, rather than a single population of cells. The relationships of breast cancer stem cells to clinical parameters will require identification of specific markers or panels for the individual cancer

The Phenotypic Radiation Resistance of CD44+/CD24−or low Breast Cancer Cells Is Mediated through the Enhanced Activation of ATM Signaling

Cancer initiating cells (CIC) are stem-like cells. CIC may contribute not only to the initiation of cancer but also to cancer recurrence because of the resistance of CIC both to chemotherapy and radiation therapy. From the MCF-7 and MDA-MB231 breast cancer cell lines and primary culture of patient breast cancer cells, we isolated by flow cytometry a CIC subset of cells with the CD44+/CD24−or low phenotype. The CD44+/CD24−or low subset showed increased sphere formation and resistance to radiation compared to the non- CD44+/CD24−or low subset. The increased radiation resistance was not dependent on the result of altered non-homologous end joining (NHEJ) DNA repair activity as both NHEJ activity and expression of the various proteins involved in NHEJ were not significantly different between the CD44+/CD24−or low and non- CD44+/CD24−or low subsets. However, activation of ATM signaling was significantly increased in CD44+/CD24−or low cells compared to non- CD44+/CD24−or low cells in both from breast cancer cell lines and primary human breast cancer cells. Application of an ATM inhibitor effectively decreased the radiation resistance of CD44+/CD24−or low subset, suggesting that targeting ATM signaling may provide a new tool to eradicate stem-like CIC and abolish the radiation resistance of breast cancer

Chronic hyperglycemia induces trans-differentiation of human pancreatic stellate cells and enhances the malignant molecular communication with human pancreatic cancer cells

BACKGROUND: Diabetes mellitus is linked to pancreatic cancer. We hypothesized a role for pancreatic stellate cells (PSC) in the hyperglycemia induced deterioration of pancreatic cancer and therefore studied two human cell lines (RLT-PSC, T3M4) in hyperglycemic environment. METHODOLOGY/PRINCIPAL FINDINGS: The effect of chronic hyperglycemia (CHG) on PSCs was studied using mRNA expression array with real-time PCR validation and bioinformatic pathway analysis, and confirmatory protein studies. The stress fiber formation (IC: αSMA) indicated that PSCs tend to transdifferentiate to a myofibroblast-like state after exposure to CHG. The phosphorylation of p38 and ERK1/2 was increased with a consecutive upregulation of CDC25, SP1, cFOS and p21, and with downregulation of PPARγ after PSCs were exposed to chronic hyperglycemia. CXCL12 levels increased significantly in PSC supernatant after CHG exposure independently from TGF-β1 treatment (3.09-fold with a 2.73-fold without TGF-β1, p<0.05). The upregualtion of the SP1 transcription factor in PSCs after CHG exposure may be implicated in the increased CXCL12 and IGFBP2 production. In cancer cells, hyperglycemia induced an increased expression of CXCR4, a CXCL12 receptor that was also induced by PSC's conditioned medium. The receptor-ligand interaction increased the phosphorylation of ERK1/2 and p38 resulting in activation of MAP kinase pathway, one of the most powerful stimuli for cell proliferation. Certainly, conditioned medium of PSC increased pancreatic cancer cell proliferation and this effect could be partially inhibited by a CXCR4 inhibitor. As the PSC conditioned medium (normal glucose concentration) increased the ERK1/2 and p38 phosphorylation, we concluded that PSCs produce other factor(s) that influence(s) pancreatic cancer behaviour. CONCLUSIONS: Hyperglycemia induces increased CXCL12 production by the PSCs, and its receptor, CXCR4 on cancer cells. The ligand-receptor interaction activates MAP kinase signaling that causes increased cancer cell proliferation and migration

Gene Expression Profiling of Liver Cancer Stem Cells by RNA-Sequencing

Background: Accumulating evidence supports that tumor growth and cancer relapse are driven by cancer stem cells. Our previous work has demonstrated the existence of CD90 + liver cancer stem cells (CSCs) in hepatocellular carcinoma (HCC). Nevertheless, the characteristics of these cells are still poorly understood. In this study, we employed a more sensitive RNA-sequencing (RNA-Seq) to compare the gene expression profiling of CD90 + cells sorted from tumor (CD90 +CSCs) with parallel non-tumorous liver tissues (CD90 +NTSCs) and elucidate the roles of putative target genes in hepatocarcinogenesis. Methodology/Principal Findings: CD90 + cells were sorted respectively from tumor and adjacent non-tumorous human liver tissues using fluorescence-activated cell sorting. The amplified RNAs of CD90 + cells from 3 HCC patients were subjected to RNA-Seq analysis. A differential gene expression profile was established between CD90 +CSCs and CD90 +NTSCs, and validated by quantitative real-time PCR (qRT-PCR) on the same set of amplified RNAs, and further confirmed in an independent cohort of 12 HCC patients. Five hundred genes were differentially expressed (119 up-regulated and 381 down-regulated genes) between CD90 +CSCs and CD90 +NTSCs. Gene ontology analysis indicated that the over-expressed genes in CD90 +CSCs were associated with inflammation, drug resistance and lipid metabolism. Among the differentially expressed genes, glypican-3 (GPC3), a member of glypican family, was markedly elevated in CD90 +CSCs compared to CD90 +NTSCs. Immunohistochemistry demonstrated that GPC3 was highly expressed in forty-two human liver tumor tissues but absent in adjacent non-tumorous liver tissues. Flow cytometry indicated that GPC3 was highly expressed in liver CD90 +CSCs and mature cancer cells in liver cancer cell lines and human liver tumor tissues. Furthermore, GPC3 expression was positively correlated with the number of CD90 +CSCs in liver tumor tissues. Conclusions/Significance: The identified genes, such as GPC3 that are distinctly expressed in liver CD90 +CSCs, may be promising gene candidates for HCC therapy without inducing damages to normal liver stem cells. © 2012 Ho et al.published_or_final_versio

Stromal SPARC expression and patient survival after chemoradiation for non-resectable pancreatic adenocarcinoma

Purpose: Pancreatic stellate cells (PSC) drive desmoplasia in pancreatic cancer. Our study analyzed both tumor and PSC, since interaction of these cell types may promote tumor progression. Results: SPARC was expressed predominantly in the peritumoral and distal stroma. SPARC in distal stroma correlated inversely with overall survival of the patients with LAPC (p = 0.013) with a relative hazard of 2.23 (95% CI, 1.05 to 4.72; p = 0.036). TGFβ1 in the tumor was also a negative prognostic factor (p = 0.03). Within the tumor cells, phospho-Akt correlated with TGFβ1, SPARC and survivin. Tumor phospho-Akt correlated with stroma phospho-Akt, tumor TGFβ1 correlated with stroma TGFβ1 and α-SMA, tumor survivin correlated with stroma survivin and distal SPARC. Within the stroma, SPARC and TGFβ1 correlated with α-SMA. Peritumoral SPARC correlated with distal SPARC. In vitro, SPARC was highly expressed in hPSC but not in Panc-1 cells. Exogenous SPARC did not change radiation resistance but increased the invasion of Panc-1 cells both in monoculture and in coculture with hPSC. Experimental design: Immunohistochemical expression of SPARC, CTGF, TGFβ1, phospho-Akt, survivin and α-SMA was analyzed prior to chemoradiation in 58 locally advanced pancreatic cancer (LAPC) biopsy specimens. Fisher's exact test served to detect associations between tumor and PSC expression of markers. Kaplan-Meier analysis and multivariate analysis were used to evaluate the association of marker expression with overall survival. SPARC expression was analyzed in human pancreatic cancer cells (Panc-1) and in human PSC (hPSC), and the effect of SPARC on the invasion of Panc-1 cells was measured in monoculture or in coculture with hPSC. Conclusions: Our hypothesis of a detrimental effect of PSC on patient survival in LAPC after chemoradiation is supported by the inverse correlation of SPARC in distal stromal cells with patients survival. Furthermore in vitro data indicate that paracrine SPARC from PSC increases the invasion of pancreatic cancer cells