Focal adhesions have been implicated in regulating cancer invasion, while the role of focal adhesions in coloncancer cells has not been well defined. To determine if the activity of PIPKIc influences focal adhesion formation in coloncancer cells, HCT116 cells that stably express EGFP-PIPKIc or -PIPKIc K188,200R were plated on fibronectin and stained for paxillin. As shown in Fig. 4A, most of the focal adhesions were located to the peripheral region, and HCT116 cells expressing PIPKIc K188,200R had much fewer focal adhesions than those expressing the WT enzyme. The average focal adhesion number in cells expressing WT PIPKIc was 22.5/cell, whereas that in cells expressing PIPKIc K188,200R was 11.5/cell, both of which were fewer than those observed in CHO-K1 cells (Fig. 4B). In addition, PIPKIc K188,200R had more effect on the smaller focal adhesions than the larger ones (Fig. 4C). To test whether PIPKIc is essential for focal adhesion formation in HCT116 cells, HCT116 cells were infected with recombinant lentiviruses that express PIPKIc shRNA or shRNA control and were selected with puromycin. As shown in Fig. 5A, expression of PIPKIc shRNA resulted in dramatic reduction in the endogenous PIPKIc level of HCT116 cells. The cells were then plated on fibronectin and stained for paxillin. Surprisingly, PIPKIc knock- down almost abolished focal adhesion formation in HCT116 cells (Fig. 5B). PIPKIc depletion reduced focal adhesion number by about 74% (Fig. 5C). Different from PIPKIc K188,200R , PIPKIc shRNA had more effect on the larger focal adhesions than the smaller ones (Fig. 5D). These results indicate an essential role of PIPKIc in focal adhesion formation in HCT116 coloncancer cells. This dramatic effect of PIPKIc knockdown did not occur in MDA- MB-231 human breast cancer cells, where PIPKIc knockdown only partially inhibited focal adhesion formation (data not shown).
Colorectal cancer is the fourth most common cancer form in humans. Each year, more than 1,200,000 individuals will develop the disease and over 600,000 will die from it . Despite the high biomedical significance of this tumor, investigations of the EZH2 status and function in coloncancer cells are sparse and partly contradictory. For example, whereas EZH2 was consistently reported to be overexpressed in colon cancers, EZH2 expression levels correlated positively , negatively [20,21], or not at all , with the survival of coloncancer patients. Moreover, to our knowledge, only one functional study investigated the role of EZH2 for the growth of coloncancer cells, but failed to see an effect upon EZH2 gene silencing . This finding is in strong contrast to the growth-promoting role of EZH2 reported for several other cancer entities [2–6]. In the present work, we addressed this issue by analyzing EZH2 expression in coloncancer cells in vitro and in vivo, and by investigating the contribution of EZH2 to the growth of colorectal cancer cell lines.
Furthermore, our current study showed that LEF1 overexpression in the primary CRC tissues was associated with distant metastasis of CRC patients, which is consistent with several previous studies documenting that LEF1 was characterized as a biomarker for coloncancer to metastasize to the liver [β1]. Indeed, our current in vitro data confirmed that knockdown of LEF1 expression inhibited invasion ability of SW480 and SW6β0 cells compared with the control shRNA- transfected cells. At the molecular level, MMPβ, MMP7 and MMP9 are associated with cell migration process, influencing cancer development and progression [β4,β5]. We found that knockdown of LEF1 expression suppressed MMPβ and MMP-9 expression, but not MMP-7, indicating that the selective modulation of MMPs by LEF1 could have the biological significance in coloncancer progression. In contrast, LEF1 was able to regulate MMP-7 expression and activity in breast cancer cells [β6], whereas another previous study showed that circulating MMP-β and MMP-9 could be used to potentially classify patients into low risk, high risk, benign disease, and breast cancer [β4]. However, our nude mouse xenograft assay did not show any tumor metastasis in both the LEF-1 knockdown and the control tumor xenografts; thus, additional studies are clearly needed.
numbers of E. coli in coloncancer samples than in controls when biopsy samples were studied after surface mucus removal, indicating that higher numbesr of E. coli are in very close association with the mucosa in CRC samples compared to those of controls. The CM-encoding genes identified were pks island, cnf1 and cdt gene. Accordingly, Bronowski et al. have previously identified among a panel of 10 E. coli isolated from biopsies of colon cancers, 3 strains harboring cnf1 genes and 4 strains harboring a polyketide synthase-encoding gene belonging to pks island . The high prevalence of CM-encoding genes in CRC suggests a possible role of CM-encoding E. coli in the development of malignant colon tumors. It is well established that colibactin- encoding pks-harboring E. coli strains are mutagenic and genotoxic in vitro and in vivo [22,23]. They can promote CRC without affecting intestinal inflammation . In addition, transient infection of human cell lines by such strains induces anchorage- independent colony formation , a process involved in metastases. Because of these mutagenic and cell transformation activities, E. coli strains harboring the colibactin-encoding pks island may affect carcinogenesis at different stages. Cdt also induces DNA breaks in eukaryotic cells . The presence of bacteria harboring cdt have already been associated with some lymphomas of the small intestine and can promote the develop- ment of hepatic and colon tumors [25,51–54]. CNF promotes cell proliferation by activating the Rho-GTPases and stimulates the transition from G 1 to S phases . In addition, CNF1 inhibits
Leuconostoc species are opportunistic pathogens that rarely encountered as an infection agent. It has been reported that, this pathogen could cause infections especially in immunsupressive patients, ater invasive procedures and antibiotic treatment. In this report, we aim to present a case with intrinsically vancomycin resistant Leuconostoc spp. that was isolated in blood culture. Fity six years old male patient with type II diabetes mellitus and chronic obstructive pulmonary disease had been operated for sigmoid coloncancer one a half years ago. He was taken radiotherapy and chemotherapy right ater the operation. The patient was admitted to our hospital with a complaint of stenosis in colostomy opening. Em- piricial treatment was started for high fever. Gram positive coccus was reported in the blood culture(Bactec 9050, Becton-Dickinson, USA). The isolate was identi- ied as Leuconostoc spp. with API 20 Strep (BioMerieux, French) kit. Antibiotic susceptibility test was performed by the disk difusion method according to CLSI (Clinical and Laboratory Standards Institute) recommendations. The isolate was found susceptible to linezolid and quinupristin-dalfopristine, while it was resistant to penicilin, ampicillin, erythromycin, tetracycline, vancomycin and teicoplanin by the disk difusion method. Vancomycin resistance was conirmed by E-test (AB Biodisk, Solna, Sweden).
Specimens were retrieved from the pathology files of the Ramon y Cajal University Hospital, Madrid, Spain, and histologically reviewed. Paraffin blocks were retrieved to construct tissue arrays containing 1,5 mm diameter tissue cylinders from coloncancer and control specimens. Each tissue array paraffin block contained at least 2 samples of each case in order to have a cross control of signal expression. The most representative areas of each tumor were selected for the study. Reactive lymphoid tissue (tonsils) were used as negative controls of expression and incorporated by triplicate in each tissue array. Histopathological features were independently reviewed. This was followed by common observa- tion on a multihead microscope, where discrepancies were resolved.
Bevacizumab is a monoclonal antibody which is targeting to vascular endothelial growth factor. It has been shown to be a promising drug on metastatic colorectal cancer and is combined with chemotherapeutic agents. One should be aware of serious complications even though bevacizumab is a well-tolerated drug. There are a few in- testinal perforation cases that have been reported in the oncologic surgery literature related to the bevacizumab treatment. In this case report, we aimed to represent a 45 years old man who was diagnosed with intestinal per- foration after bevacizumab treatment ten months after a metastatic coloncancer surgery.
This is the first study that correlated the DMH- induced coloncancer and testicular structure and the effect of a long-term swimming program on the testis of Wistar rats with coloncancer. The coloncancer is associated with a good prognostic and possibilities of cure. Hence, the study of the impairment caused by this disease on testis structure was a contribution toward the future research looking for the ways to reduce this damage and maintain male fertility after cancer treatment. Previous studies have shown reduction of coloncancer incidence with exercise (Friedenreich and Orenstein 2002; Demarzo et al. 2008; Lunz et al. 2008). Hence, it was considered as important to investigate if regular swimming exercise attenuated, or accentuated the testicular impairment caused by the coloncancer in Wistar rat testes.
observed that SIRT1 expression in the normal intestine occurs specifically in the enterocytes, the precursor cells that undergo neoplastic transformation in colon cancers and that SIRT1 is upregulated in rodent intestines in response to CR. We show that overexpression of SIRT1 reduces proliferation in coloncancer cell lines and that overexpressing SIRT1 in the enterocytes of APC min/+ animals mimics the tumor suppressive effects of CR on this colon Figure 1. Generation of the conditional SIRT1 transgenic mice that mimic calorie restriction induced SIRT1 overexpression. (A) Western blot analysis showing expression levels in the gut epithelium of SIRT1 in ad libitum-fed (AL) or calorie restricted (CR) rats. b-actin served as the loading control in all lanes. (B) Schematic representation of the strategy used for the generation of the floxed SIRT1 mouse embryonic stem (MES) cells. SIRT1 was cloned downstream of a constitutive CAGGS promoter followed by a transcriptional loxP-STOP-loxP cassette. This construct was specifically targeted in the 39 UTR of the collagen A1 locus (ColA1) of mouse embryonic stem cells (MES) cells by FLP recombination. The targeted MES cells were injected into blastocysts. Red arrows indicate location of the SIRT1-Tg genotyping primers. (C) Southern blot showing the confirmation of the SIRT1 STOP single integration into the Col1A locus of MES cells. (D) PCR confirming the germline transmission of the SIRT1 STOP transgene to the chimaeras’ offspring. (E) Western blot showing the levels of SIRT1 in the triple transgenic mice overexpressing SIRT1 (SIRT1 DSTOP ) and
GPx2-KO mice developed fewer tumors on 2Se or ++Se diets and fewer MDF on the +Se diet than respective WT mice (Fig. 2A and D). This indicates that GPx2-KO mice are more resistant to AOM-induced cancer. In contrast, GPx2-KO mice developed more tumors in an AOM/DSS-induced coloncancer model , which correlated with a more severe DSS-colitis upon GPx2 deletion. Thus, the anti-carcinogenic activity of GPx2 in inflammation-triggered coloncancer is mainly caused by its anti- inflammatory role. The pro-carcinogenic activity of GPx2 after AOM-treatment alone highlights the crucial impact of the DSS- colitis as a tumor-driving force in the AOM/DSS model. AOM induces G/A base conversions which mainly result in activating mutations in b-catenin. These mutations are counteracted by one microadenoma (C). Florid inflammation in AOM-treated, 2Se GPx2-KO mice was identified by PAS/AB, F4/80, and H&E staining (D). Spleen weights were normalized to body weight (E). Means +SD, n = 10 in saline-treated and n = 20 in AOM-treated groups. Significance was determined using 2-way ANOVA with Bonferroni’s post-test. *P#0.05 vs. WT, x P#0.05 vs. saline.
expression and subsequent TGF-b signaling. Compared to the C allele, the risk allele G forms weaker protein–DNA complexes with nuclear extracts and was associated with a reduced expression of SMAD7 in the colorectum. However, it remains unclear how such alterations may promote carcinogenesis. It has been suggested that SMAD7 may induce tumorigenicity by blocking TGF-b-induced growth inhibition and apoptosis . The expression of SMAD7 is very low in epithelial tissues, but is up-regulated in several cancers. Over-expression of SMAD7 has been shown to inhibit TGF-b- mediated induction of endogenous heme oxygenase-1 (HO-1) gene expression , an adaptive defense against oxidant stress . In coloncancer cells, stable expression of SMAD7 blocks the TGF-b- mediated activation of NFkB, a critical molecule in oxidative- stress-induced apoptosis. In addition, CRC patients with deletion Table 2. SMAD7 tagging SNPs and colorectal cancer risk in the ColonCancer Family Registry.
KRAS-mutant vectors to generate paired CRC cells. These paired CRC cells were tested by oxaliplatin, irinotecan and 5FU to determine the change in drug sensitivity by MTT assay and flow cytometry. Reasons for sensitivity alteration were further determined by western blot and real-time quantitative reverse transcriptase polymerase chain reaction (qRT -PCR). In KRAS- wild-type CRC cells (COLO320DM), KRAS overexpression by mutant vectors caused excision repair cross-complementation group 1 (ERCC1) downregulation in protein and mRNA levels, and enhanced oxaliplatin sensitivity. In contrast, in KRAS- mutant CRC cells (DLD-1 G13D and SW480 G12V ), KRAS knocked-down by KRAS-siRNA led to ERCC1 upregulation and increased oxaliplatin resistance. The sensitivity of irinotecan and 5FU had not changed in the paired CRC cells. To validate ERCC1 as a predictor of sensitivity for oxaliplatin, ERCC1 was knocked-down by siRNA in KRAS-wild-type CRC cells, which restored oxaliplatin sensitivity. In contrast, ERCC1 was overexpressed by ERCC1-expressing vectors in KRAS-mutant CRC cells, and caused oxaliplatin resistance. Overall, our findings suggest that KRAS mutation is a predictor of oxaliplatin sensitivity in coloncancer cells by the mechanism of ERCC1 downregulation.
Only recently have the effects of a dominant active PI3K pathway been explored in the mammalian intestine. Our group was the first to describe the development of hyperplasia and invasive mucinous adenocarcinomas developing in the proximal colon as a result of expression of a dominant active PI3K (Pik3ca p110 ) . The cancers in this model developed through a non-canonical pathway without the identification of a polypoid intermediary and without acti- vation of WNT signaling. To determine if similar tumors could be initiated in the setting of a hotspot mutation in PIK3CA commonly encountered in human cancers, we developed the Fc + Pik3ca H1047R murine model. Here we demonstrate that the Pik3ca H1047R mutation results in hyperplasia and the development of mucinous adenocarcinomas within the colon indistin- guishable from the Fc + Pik3ca p110 mice. The predominant difference between these two mod- els is the latency in which these tumors develop. In the Fc + Pik3ca p110 model, ~75% of mice had invasive cancers by 40 days of age , while in the Fc + Pik3ca H1047R mice no tumors were identified at 50 days of age and only 65% of mice had tumors at necropsy (age 97–310 days). These cancers appear to be developing through a similar mechanism with activation of the PI3K pathway and without activation of WNT signaling. The increased latency in cancer devel- opment in the Fc + Pik3ca H1047R mice appears related to a decreased level of activation of the PI3K pathway compared to the Fc + Pik3ca p110 mice.
The mechanisms of action for the IL-22 -429 TT genotype and T allele as risk factors for bladder cancer are still unclear. IL-22 may play a role in controlling tumor growth and tumor progression by inhibiting signaling pathways that promote tumor cell proliferation, such as ERK1/2 and AKT phos- phorylation (37). The IL-22 -429 C/T gene polymorphism has been associated with the risks for various cancers. Genetic polymorphisms and plasma levels of IL-22 contribute to the development of non-small cell lung cancer (38). Recently, a case-control study found that the IL-22 -429 C/T gene polymorphism might be associated with the risk and multifocality of papillary thyroid cancer (26). In 561 coloncancer cases and 722 population controls, an association study suggested that the rs1179251 SNP in IL-22 was associated with the risk of coloncancer (23).
Colon and rectal cancer share many features and are often referred to as colorectal cancer. Some studies grouped them together [6,7] and some did not. As for dietary factors, methionine was associated with a decreased risk of proximal coloncancer among men and rectal cancer among women , while other reported only protective in rectal cancer . Vitamin B-6 was positively associated with rectal cancer but protective in both colon and rectal cancer in another [10,11]. One meta-analysis showed that vitamin D decreased both colon and rectal cancer [8,12]. Increasing intakes of calcium and insoluble dietary fiber have been associated with a decreasing risk of coloncancer. Carbohydrate intake was positively correlated with the risk of rectal cancer and fat consumption was inversely correlated with the risk of female colon and rectal cancers . Consumption of red meat and processed meat was positively associated with risk of both colon and rectal cancer, with stronger association with red meat for Table 5. Cox’s regression for colorectal cancer.
The good results achieved in dif- ferent studies regarding local control of CRC and survival rates confirm that en bloc multivisceral resections should be the standard treatment of locally advanced coloncancer for a selected group of patients. Some studies com- paring extended and classic surgeries found that the presence of positive margins was associated with poor sur- vival rates. 8,16,24 There is no 5-year sur-
Patient who present locally advanced right coloncancer may have a variety of clinic conditions. The main findings that have been described are: gastrointestinal bleeding, anorexia, weight loss and diarrhea. Sometimes, diarrhea may indicate a duodenocolic fistula.
Brooks D, Andrews KS, Dash C, Giardiello FM, Glick S, Levin TR, Pickhardt P, Rex DK, Thorson A, Winawer SJ; American Cancer Society Colorectal Cancer Advisory Group; US Multi-Society Task Force; American College of Radiolog y ColonCancer Committee. Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: a joint guideline from the American Cancer Society, the US Multi- Society Task Force on Colorectal Cancer, and the American College of Radiology. CA Cancer J Clin 2008; 58(3): 130-60.
Cancers are characterized by the deregulation of cell signaling pathways at multiple steps. However, most current anticancer therapies involve the modulation of a single target. The lack of safety and high cost of mono targeted therapies have encouraged alternative approaches. Cancer is a major public health burden in both developed and developing countries. It was estimated that there were 10.9 millions new cases, 6.7 million deaths, and 24.6 million persons living with cancer around the world .There is a compelling evidence from epidermiological and experimental studies that highlight the importance of compounds derived from plants phytochemicals to reduce the risk of coloncancer and inhibit the development and spread of tumors in experimental animals. The advantage of using such compounds for cancer treatment is their relatively non-toxic nature and availability in an ingestive form . Plants have long history of use in the treatment of cancer. Several studies have been conducted on herbs under a multitude of ethnobotanical grounds. For example, Hartwell has collected data on about 3000 plants, those of which possess anticancer properties are subsequently used as potent anticancer drugs . Plant secondary metabolites and their semi-synthetic derivatives continue to play an important role in anticancer drug therapy . These include vinblastine, vincristine, the camptothecin derivatives, topotecan and irinotecan, etoposide, derived from epipodophyllotoxin and paclitaxel (Taxol). Several promising new agents are in clinical development based on selective activity against cancer related molecular targets, including flavopiridol and combretastin A4 phosphate, and some agents which failed in earlier clinical studies are stimulating renewed interest. Sixty percent of currently used anticancer agents are derived in one way or another from natural sources .
channels are mostly expressed in primary sensory neurons and that they are naturally activated by heat or by capsaicin, protons, and anandamide . We show evidence that TRPV1 acts as a general cellular stress sensor, which in addition of being a thermosensor, elicits a heat-shock-like cellular stress response following heat or other chemical treatments in epithelial cells, such as in the lungs, as well as in various cancerous cells. We demonstrate that treatment of human embryonic kidney cells, alveolar epithelial cells, human breast cancer cells or coloncancer cells with heat, or TRPV1 agonists, capsaicin or RTX, induced the accumulation of Hsp70, Hsp90 and Hsp27, and Hsp70 and Hsp90, respectively, which are hallmarks of the cellular heat-shock response. Thus, in addition to the well-established ability of capsaicin to induce isothermally the activation of an inter-cellular signal resulting in the deceptive sensation of heat , TRPV1 agonists can also induce an intracellular signal resulting in the synthesis of HSPs. Further, we show by immunoblots, RT-PCR and Gel-shift assays that capsaicin treatment resulted in the isothermal activation of HSF-1, suggesting that TRPV1, the only known capsaicin target, is directly responsible for the heat or the chemical signal that up-regulates the heat shock genes, and the cellular heat shock response (HSR) in general. In support of these findings, we found that cells devoid of the TRPV1 gene, could not over express Hsp70 in response to heat-shock or capsaicin treatments. Further, we show that in cells harboring TRPV1, Figure 2. TRPV1 mRNA and protein abundances in HEK-293e cells. A. Semi-quantitative RT-PCR for TRPV1. Upper left panel: mRNA levels from PC3 prostate cancer cells: non treated cells, cells treated with 32 mM capsaicin for 1 hr and cells treated with heat shock at 42uC for 3 hrs. Lower right panel: mRNA levels of GAPDH as well as densitometric. Upper right panel: mRNA levels from HEK-293e cells: non treated cells, cells treated with 32 mM capsaicin for 1 hr (Caps), cells treated with heat shock at 42uC for 3 hrs, and cells treated with heat shock at 42uC for 3 hrs with the addition of 32 mM capsaicin. Lower right Panel: mRNA levels of GAPDH as well as densitometry. B. Representative immunoblot analysis of TRPV1 abundance. TRPV1 was detected in HEK-293e cells. Cells in culture were incubated with 0.01% DMSO or treated with 4 mM, 16 mM or 32 mM of capsaicin for 1 hr. C. Representative immunoblot analysis of TRPV1 and Hsp90 abundances in HEK-293e cells. Cells were treated with 32 mM capsaicin for 0 hr, 1 hr, 4 hrs and 6 hrs.