MicroRNAs (miRNA) have rapidly emerged as modulators of gene expression in cancer in which they may have great diagnostic and therapeutic import. MicroRNA-199a-3p (miR-199a-3p) is downregulated in ...several human malignancies including hepatocellular carcinoma (HCC). Here, we show that miR-199a-3p targets mammalian target of rapamycin (mTOR) and c-Met in HCC cells. Restoring attenuated levels of miR-199a-3p in HCC cells led to G(1)-phase cell cycle arrest, reduced invasive capability, enhanced susceptibility to hypoxia, and increased sensitivity to doxorubicin-induced apoptosis. These in vitro findings were confirmed by an analysis of human HCC tissues, which revealed an inverse correlation linking miR-199a-3p and mTOR as well as a shorter time to recurrence after HCC resection in patients with lower miR-199a-3p expression. These results suggest that tactics to regulate mTOR and c-Met by elevating levels of miR-199a-3p may have therapeutic benefits in highly lethal cancers such as HCC.
The identification of target genes is a key step for assessing the role of aberrantly expressed microRNAs (miRNA) in human cancer and for the further development of miRNA-based gene therapy. MiR-122 ...is a liver-specific miRNA accounting for 70% of the total miRNA population. Its down-regulation is a common feature of both human and mouse hepatocellular carcinoma (HCC). We have previously shown that miR-122 can regulate the expression of cyclin G1, whose high levels have been reported in several human cancers. We evaluated the role of miR-122 and cyclin G1 expression in hepatocarcinogenesis and in response to treatment with doxorubicin and their relevance on survival and time to recurrence (TTR) of HCC patients. We proved that, by modulating cyclin G1, miR-122 influences p53 protein stability and transcriptional activity and reduces invasion capability of HCC-derived cell lines. In addition, in a therapeutic perspective, we assayed the effects of a restored miR-122 expression in triggering doxorubicin-induced apoptosis and we proved that miR-122, as well as cyclin G1 silencing, increases sensitivity to doxorubicin challenge. In patients resected for HCC, lower miR-122 levels were associated with a shorter TTR, whereas higher cyclin G1 expression was related to a lower survival, suggesting that miR-122 might represent an effective molecular target for HCC. Our findings establish a basis toward the development of combined chemo- and miRNA-based therapy for HCC treatment.
Patients with long-standing ulcerative colitis (UC) have an increased colorectal cancer (CRC) risk. In this pilot study we evaluated the effect of Eicosapentaenoic acid as free fatty acid (EPA-FFA) ...supplementation on mucosal disease activity, colonic differentiation markers and microbiota composition in UC patients. Twenty long-standing UC patients in stable clinical remission and with fecal calprotectin (FC) > 150 µg/g were enrolled (T0) and supplemented with EPA-FFA 2 g/daily for 90 days (T3). Endoscopic and histologic disease activities were measured by Mayo and Geboes scores, respectively. HES1, KLF4, STAT3, IL-10 and SOCS3 levels were determined using western blotting and qRT-PCR, while phospho-STAT3 levels were assessed by western blotting. Goblet cells were stained by Alcian blue. Microbiota analyses were performed on both fecal and colonic samples. Nineteen patients completed the study; seventeen (89.5%) were compliant. EPA-FFA treatment reduced FC levels at T3. Patients with FC > 150 µg/g at T3 (n = 2) were assumed as non-responders. EPA-FFA improved endoscopic and histological inflammation and induced IL-10, SOCS3, HES1 and KLF4 in compliant and responder patients. Importantly, long-term UC-driven microbiota composition was partially redressed by EPA-FFA. In conclusion, EPA-FFA supplementation reduced mucosal inflammation, promoted goblet cells differentiation and modulated intestinal microbiota composition in long-standing UC patients.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Our goal has been to evaluate the importance that the incorporation of Bcl2 in the ER/PGR/Her2/Ki67 bio-profile can have as predictor of the Oncotype Dx categories.
156 consecutive cases of HR+/Her2- ...pN0/1 primary breast carcinoma were sent to the Oncotype Dx test. Immunohistochemical determination of Bcl2/ER/PGR/Ki67/Her2 expression was evaluated for each case. After the selection of the appropriate cut-off values for PGR and Ki67, explorative as well as confirmative statistical analyses were performed to build and validate predictive risk-of-recurrence immunohistochemical only bio-profiles.
The predictive capacity of these immunohistochemical profiles was compared with both traditional and TAILORx Oncotype Dx risk class classification. This comparison showed that immunohistochemical bio-profiles select those cases not associated with high risk-of-recurrence of disease (luminal-A/B and luminal A/B Bcl2) and those that are instead at high risk and therefore worthy of chemotherapy (luminal-B ki67 and luminal-B Bcl2/Ki67), strongly suggesting to only submit PGR-positive/Bcl2-Ki67 altered cases to Oncotype Dx, thus reducing the number of cases to be tested.
Our results indicate that the addition of Bcl2 to an immunohistochemical bio-profile definitely improves its predictive capacity to correctly select which cases to send to the Oncotype Dx test. We have also suggested that institutions with a significant number of breast carcinomas sent to the Oncotype Dx test can use these latter to derive their own PGR and Ki67 cut-off values, overcoming the drawbacks of sharing common inter-laboratory values. Validation of these bio-profiles as predictors of the Oncotype Dx categories is ongoing in a prospective series of new cases.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Inflammatory bowel diseases are associated with increased risk of developing colitis‐associated colorectal cancer (CAC). Epidemiological data show that the consumption of ω‐3 polyunsaturated fatty ...acids (ω‐3 PUFAs) decreases the risk of sporadic colorectal cancer (CRC). Importantly, recent data have shown that eicosapentaenoic acid‐free fatty acid (EPA‐FFA) reduces polyp formation and growth in models of familial adenomatous polyposis. However, the effects of dietary EPA‐FFA are unknown in CAC. We tested the effectiveness of substituting EPA‐FFA, for other dietary fats, in preventing inflammation and cancer in the AOM‐DSS model of CAC. The AOM‐DSS protocols were designed to evaluate the effect of EPA‐FFA on both initiation and promotion of carcinogenesis. We found that EPA‐FFA diet strongly decreased tumor multiplicity, incidence and maximum tumor size in the promotion and initiation arms. Moreover EPA–FFA, in particular in the initiation arm, led to reduced cell proliferation and nuclear β‐catenin expression, whilst it increased apoptosis. In both arms, EPA‐FFA treatment led to increased membrane switch from ω‐6 to ω‐3 PUFAs and a concomitant reduction in PGE2 production. We observed no significant changes in intestinal inflammation between EPA‐FFA treated arms and AOM‐DSS controls. Importantly, we found that EPA‐FFA treatment restored the loss of Notch signaling found in the AOM‐DSS control and resulted in the enrichment of Lactobacillus species in the gut microbiota. Taken together, our data suggest that EPA‐FFA is an excellent candidate for CRC chemoprevention in CAC.
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Recent clinical data show that, as yet, there is no agent clearly protecting against colorectal cancer (CRC) development in long‐standing inflammatory bowel diseases. This study tests the effect of dietary supplementation with eicosapentaenoic acid, as free fatty acid (EPA‐FFA), in a mouse model of colitis‐associated CRC. The results demonstrate for the first time that EPA‐FFA is an effective chemopreventive agent during both initiation and promotion of colitis‐associated colorectal cancer in mice, with changes in Notch1 signaling and gut microbiota composition. Early EPA‐FFA supplementation could thus be a good strategy for CRC prevention in subjects affected by inflammatory bowel diseases.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Basal-like carcinoma are aggressive breast cancers that frequently carry p53 inactivating mutations, lack estrogen receptor-α (ERα) and express the cancer stem cell markers CD133 and CD44. These ...tumors also over-express Interleukin 6 (IL-6), a pro-inflammatory cytokine that stimulates the growth of breast cancer stem/progenitor cells.
Here we show that p53 deficiency in breast cancer cells induces a loss of methylation at IL-6 proximal promoter region, which is maintained by an IL-6 autocrine loop. IL-6 also elicits the loss of methylation at the CD133 promoter region 1 and of CD44 proximal promoter, enhancing CD133 and CD44 gene transcription. In parallel, IL-6 induces the methylation of estrogen receptor (ERα) promoter and the loss of ERα mRNA expression. Finally, IL-6 induces the methylation of IL-6 distal promoter and of CD133 promoter region 2, which harbour putative repressor regions.
We conclude that IL-6, whose methylation-dependent autocrine loop is triggered by the inactivation of p53, induces an epigenetic reprogramming that drives breast carcinoma cells towards a basal-like/stem cell-like gene expression profile.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The comprehension of the basic biology of stem cells is expected to provide a useful insight into the pathogenesis of cancer. In particular, there is evidence that hypoxia promotes stem cell renewal ...in vitro as well as in vivo. It therefore seems reasonable that stem cell survival and hypoxia response are strictly connected at molecular level. We here report that the 66-kDa isoform of the SHC gene (p66Shc) is induced in a breast cancer cell line by the exposure to hypoxic environment and that it controls the expression of the stem cell regulatory gene Notch-3. Then, we show that p66Shc/Notch-3 interplay modulates self-renewal (by inducing the Notch-ligand Jagged-1) and hypoxia survival (by inducing the hypoxia-survival gene carbonic anhydrase IX) in mammary gland stem/progenitor cells, expanded in vitro as multicellular spheroids (mammospheres). We conclude that mechanisms that regulate stem cell renewal and hypoxia survival are integrated at the level of the p66Shc/Notch3 interplay. Because Notch-3, Jagged-1, and carbonic anhydrase IX are dysregulated in breast cancer, and because p66Shc is an aging-regulating gene, we envision that these data may help in understanding the relationship among aging, cancer, and stem cells.
The overexpression of microRNA-221 (miR-221) is reported in several human cancers including hepatocellular carcinoma, and its targeting by tailored treatments has been proposed. The evidence ...supporting the role of miR-221 in cancer is growing and has been mainly focused on the discovery of miR-221 targets as well as on its possible therapeutic exploitations. However, the mechanism sustaining miR-221 aberrant expression remains to be elucidated. In this study, MDM2 (E3 ubiquitin-protein ligase homolog), a known p53 (TP53) modulator, is identified as a direct target of miR-221, and a feed-forward loop is described that sustains miR-221 aberrant expression. Interestingly, miR-221 can activate the p53/mdm2 axis by inhibiting MDM2 and, in turn, p53 activation contributes to miR-221 enhanced expression. Moreover, by modulating the p53 axis, miR-221 impacts cell-cycle progression and apoptotic response to doxorubicin in hepatocellular carcinoma-derived cell lines. Finally, CpG island methylation status was assessed as a causative event associated with miR-221 upregulation in hepatocellular carcinoma cells and primary tumor specimens. In hepatocellular carcinoma-derived cell lines, pharmacologically induced DNA hypomethylation potentiated a significant increase in miR-221 expression. These data were confirmed in clinical specimens of hepatocellular carcinoma in which elevated miR-221 expression was associated with the simultaneous presence of wild-type p53 and DNA hypomethylation.
These findings reveal a novel miR-221-sustained regulatory loop that determines a p53-context-specific response to doxorubicin treatment in hepatocellular carcinoma.
Background: Malignant bowel obstruction (MBO) is often the latest stage in ovarian cancer (OC). The therapy of this condition ranges from medical waiting to surgery. The objective of this pilot study ...is to compare the two strategies so that we can provide a path forward for future studies. Methods: From 700 women diagnosed with OC in the database of the Division of Gynecologic Oncology we crossed the names of those admitted by the emergency services of the IRCSS Azienda Ospedaliero Universitaria of Bologna, Italy. We selected MBO patients with a history of OC as the only neoplastic condition and compared the results between medical conduct and surgery to restore intestinal transit. Results: Of the 700 women in our database, 36 were eligible for study according to the inclusion and exclusion criteria: 9 in surgery group and 27 in medical group. Surgical conduct (tumor biopsy and stoma) appears to be resolutory for the obstruction and have a better result than medical therapy regarding recurrence of MBO, despite the development of greater complications. Relapses of MBOs occurred in 11% of surgical patients and 44% of medical patients (p = 0.0714). Furthermore, after surgical treatment, five patients (55%) experienced postoperative complications; in four cases, severe anemia requiring blood transfusion, while one patient developed post-surgical sepsis, which evolved into multiple organ failure and death. Of the 9 patients treated surgically, 2 (22%) were given surgery as a first choice. In most cases (78%), surgery was decided upon when medical treatment failed. The only discriminative factor appears to be age. The length of hospitalization increased with the patient’s age (p = 0.0181) as statistically significant factors for a worse outcome in surgery. Conclusions: MBO requires complex and multidisciplinary management where different factors need to be considered before initiating surgical therapy. Future studies are needed to deal with this complex problem.