A Four-Gene Panel in Rectal Swab Samples as a Biomarker for Colorectal Cancer Screening.

BACKGROUND: The dysregulation of gene expression is one of the key molecular features of colorectal cancer (CRC) development. This study aimed to investigate whether such dysregulation is reflected in rectal swab specimens of CRC patients and to evaluate its potential as a non-invasive approach for screening. METHODS: We compared the expression level of 14 CRC-associated genes in tumor and adjacent non-tumor tissue of CRC patients and examined the correlation of their levels in tissue with paired rectal swab specimens. The level of these 14 genes in rectal swab specimens was compared among patients with CRC or polyp and control subjects, and the diagnostic potential of each dysregulated gene and the gene panel were evaluated. RESULTS: The expression of CXCR2, SAA, COX1, PPARδ, PPARγ, Groγ, IL8, p21, c-myc, CD44 and CSF1 was significantly higher in CRC, and there was a significant correlation in the levels of most of them between the CRC and rectal swab specimens. In the training study, we showed that CD44, IL8, CXCR2 and c-myc levels were significantly higher in the rectal swab specimens of the CRC patients. Such result was confirmed in the validation study. A panel of these four genes was developed, and ROC analysis showed that this four-gene panel could identify CRC patients with an AUC value of 0.83 and identify overall polyp and precancerous adenoma patients with AUC values of 0.6522 and 0.7322, respectively. Finally, the predictive study showed that the four-gene panel demonstrated sensitivities of 63.6%, 76.9% and 88.9% in identifying overall polyp, precancerous adenoma and CRC patients, respectively, whereas the specificity for normal subjects was 72.2%. CONCLUSION: The expression of CRC-associated genes in rectal swab specimens reflects the dysregulation status in colorectal tissue, and the four-gene panel is a potential non-invasive biomarker for early precancerous adenoma and CRC screening.

High Expression of a Cancer Stemness-Related Gene, Chromobox 8 (CBX8), in Normal Tissue Adjacent to the Tumor (NAT) Is Associated with Poor Prognosis of Colorectal Cancer Patients.

BACKGROUND: Several studies have demonstrated that the molecular profile of normal tissue adjacent to the tumor (NAT) is prognostic for recurrence in patients with different cancers. This study investigated the clinical significance of CBX8 gene expression, a cancer stemness-related gene, in tumor and NAT tissue of colorectal cancer (CRC) patients. METHODS: The gene level of CBX8 in paired CRC and NAT specimens from 95 patients was determined by quantitative PCR. CBX8 protein level in CRC and NAT specimens from 66 patients was determined by immunohistochemistry. CBX8 gene and protein levels were correlated with the patients' clinicopathological parameters and circulatory immune cell profiles. The association between CBX8 and pluripotency-associated genes was analyzed using the TCGA database. RESULTS: NAT CBX8 gene level positively correlated with TNM stage, tumor invasion, lymph node metastasis and distant metastasis, indicating its association with tumor progression and metastasis. There was no correlation between NAT CBX8 protein level and clinicopathological parameters. Moreover, a high level of CBX8 gene and protein in NAT both correlated with poor DFS and OS. There was an inverse correlation between CBX8 gene level and post-operative platelet counts and platelet to lymphocyte level, suggesting its association with systematic inflammation. Finally, TCGA analysis showed that CBX8 level was correlated with a couple of pluripotency-associated genes, supporting its association with cancer stemness. CONCLUSIONS: High NAT CBX8 is a poor prognostic factor for tumor progression and survival in CRC patients.

MiR-509-3p is oncogenic, targets the tumor suppressor PHLPP2, and functions as a novel tumor adjacent normal tissue based prognostic biomarker in colorectal cancer.

BACKGROUND: Recently the role of microRNAs has been explored immensely as novel regulators and potential biomarkers in several cancers. MiR-509-3p is one such miRNA that has been observed to show a mixed expression in different cancers, while it's expression and clinical relevance in colorectal cancer (CRC) has not yet been characterized. METHODS: We used quantitative PCR to evaluate the expression of miR-509-3p in fresh-frozen CRC tumor tissues and the corresponding tumor-adjacent normal (NAT) tissues from 103 patients. Subsequently, functional studies were performed to further interpret the role of the miRNA in CRC. RESULTS: MiR-509-3p was found to be overexpressed in CRC tissues in nearly 80% of cases and was associated with an aggressive disease presentation. Notably, a higher expression of the miRNA promoted cell proliferation, migration, and invasion of CRC cells in in vitro and in vivo models. Mechanistically, we confirmed that miR-509-3p directly binds the 3'UTR of the tumor suppressor PHLPP2 and inhibits its expression. Furthermore, within the previous 103 clinical tissue specimens, we observed an overexpression of miR-509-3p within the NAT tissue of patients associated with a poor disease prognosis. Using multivariate analysis, it was observed that the expression of miR-509-3p within the NAT tissue was an independent predictor of prognosis in CRC. At the cellular level, through indirect coculture experiments, miR-509-3p was observed to regulate the proliferative, migratory, and invasive behavior of normal colon cells. CONCLUSION: MiR-509-3p strongly contributes to the development and progression of CRC and can potentially function as a prognostic biomarker in the disease.

CD26 Induces Colorectal Cancer Angiogenesis and Metastasis through CAV1/MMP1 Signaling.

CD26 has been reported as a marker for colorectal cancer stem cells endowed with tumor-initiating properties and capable of colorectal cancer (CRC) metastasis. In this study, we investigated the functional effect of CD26 on CRC angiogenesis and metastasis, and the potential underlying mechanism. The functional effects of CD26 overexpression or repression were determined by a wound healing experiment, and cell migration and invasion assays in vitro and in mouse models. Differentially expressed genes regulated by CD26 were identified by genome-wide mRNA expression array and validated by quantitative PCR. CD26 functionally regulated CRC cell migration and invasion in vitro and angiogenesis and metastasis in vivo. Genome-wide mRNA expression array and qPCR showed that MMP1 was up-regulated in CD26+ subpopulation, and a subsequent experiment demonstrated the regulatory effect of CD26 on MMP1 in CRC cell lines with CD26 repression or overexpression. Furthermore, overexpression of CAV1 abrogated the CD26-regulated MMP1 induction in CRC cell lines. This study demonstrated the functional roles of CD26 in inducing CRC migration, invasion, angiogenesis and metastasis and identified the potential involvement of MMP1 and CAV1 in such process. CD26 is an attractive therapeutic target for combating tumor progression to improve the prognosis of CRC patients.

Small RNA Profiling of piRNAs in Colorectal Cancer Identifies Consistent Overexpression of piR-24000 That Correlates Clinically with an Aggressive Disease Phenotype.

Piwi-interacting RNAs (piRNAs) represent a novel class of small non-coding RNAs (ncRNAs) that have been shown to have a deregulated expression in several cancers, although their clinical significance in colorectal cancer (CRC) remains unclear. With an aim of delineating the piRNA distribution in CRC, we conducted a systematic discovery and validation of piRNAs within two clinical cohorts. In the discovery phase, we profiled tumor and adjacent normal tissues from 18 CRC patients by deep sequencing and identified a global piRNA downregulation in CRC. Moreover, we identified piR-24000 as an unexplored piRNA that was significantly overexpressed in CRC. Using qPCR, we validated the overexpression of piR-24000 in 87 CRC patients. Additionally, we identified a significant association between a high expression of piR-24000 and an aggressive CRC phenotype including poor differentiation, presence of distant metastases, and a higher stage. Lastly, ROC analysis demonstrated a strong diagnostic power of piR-24000 in discriminating CRC patients from normal subjects. Taken together, this study provides one of the earliest large-scale reports of the global distribution of piRNAs in CRC. In addition, piR-24000 was identified as a likely oncogene in CRC that can serve as a biomarker or a therapeutic target.

Overexpression of Pin1 and rho signaling partners correlates with metastatic behavior and poor recurrence-free survival of hepatocellular carcinoma patients.

BACKGROUND: Identification of molecular markers for early detection or prediction of metastasis is crucial for both management of HCC patient postoperative treatment and identify new therapeutic targets to inhibit HCC progression and metastasis. In the current study, we investigated the clinical correlation between Pin1, RhoA and RhoC and their association with HCC metastasis. METHODS: Using a randomized study design of primary HCC samples from 139 patients, we determined messenger RNA expression of Pin1, RhoA and RhoC and their prognostic value. RESULTS: Our findings demonstrated for the first time the clinical correlation of Pin1 in HCC metastasis. Pin1, RhoA and RhoC transcript levels were significantly higher in HCC specimens when compared with the paired adjacent non-tumorous liver. Pin1 overexpression was closely correlated with that of RhoA (R = 0.562, p < 0.001) and RhoC (R = 0.529, p < 0.001), and their co-overexpressions correlated with metastatic HCC (p = 0.000012) and poor recurrence-free survival of HCC patients (p < 0.00001), which showed better prognostic significance than either Pin1, RhoA or RhoC overexpression alone. Co-overexpressions of Pin1 + RhoA/RhoC were also an independent factor for predicting development of metastasis after curative resection in our multivariate regression model (p < 0.001). CONCLUSION: Pin1, RhoA and RhoC co-overexpressions are prognostic factor for metastatic HCC and predict poor recurrence-free survival.

Suppression of Slit3 induces tumor proliferation and chemoresistance in hepatocellular carcinoma through activation of GSK3ß/ß-catenin pathway.

BACKGROUND: It is essential to understand the mechanisms responsible for hepatocellular carcinoma (HCC) progression and chemoresistance in order to identify prognostic biomarkers as well as potential therapeutic avenues. Recent findings have shown that SLIT3 appears to function as a novel tumor suppressor gene in various types of cancers, yet its clinical correlation and role in HCC has not been understood clearly. METHODS: We determined the transcript levels of Slit3 in tumor and adjacent normal tissues within two cohorts (N = 40 and 25) of HCC patients, and correlated the gene expression with the clinicopathological data. Subsequently, the functional effects and underlying molecular mechanisms of Slit3 overexpression and/or repression were studied using cell-line and mouse models. RESULTS: Our results demonstrated a repression in Slit3 expression in nearly 50% of the HCC patients, while the overall expression of Slit3 inversely correlated with the size of the tumor in both cohorts of patients. Stable down-regulation of Slit3 in HCC cell-lines induced cell proliferation in vitro and tumor growth in vivo, while stable Slit3 overexpression repressed these effects. Molecular investigations showed that the stable Slit3 repression-induced cell proliferation was associated with a higher expression of ß-catenin and a repressed GSK3ß activity. Moreover, Slit3-repression induced chemoresistance to sorafenib, oxaliplatin and 5-FU through impairment of ß-catenin degradation and induction of cyclin D3 and survivin levels. The effects induced by stable Slit3-repression were diminished by transient repression of ß-catenin by siRNA approach. CONCLUSION: This study suggests that Slit3 acts as a tumor suppressor in HCC by repressing the tumor growth and thus tumor progression. Low Slit3 level indicates a poor response of HCC cells to chemotherapy. Restoration or overexpression of Slit3 is a potential therapeutic approach to repress the tumor growth and enhance the efficacy of chemotherapeutic agents.

Identification of microRNA 885-5p as a novel regulator of tumor metastasis by targeting CPEB2 in colorectal cancer.

Colorectal cancer is the third most common cancer in the world and liver is the most frequent site of distant metastasis with poor prognosis. The aim of this study is to investigate microRNAs leading to liver metastasis. We applied microarray analysis and quantitative PCR to identify and validate dysregulated miRNAs in liver metastases when compared to primary CRCs. Functional significance and the underlying molecular mechanism of selected miRNA was demonstrated by a series of in vitro and in vivo assays. Our microarray analysis and subsequent quantitative PCR validation revealed that miR-885-5p was strongly up-regulated in liver metastases and in CRC cell-lines derived from distant metastases. Overexpression of miR-885-5p significantly induced cell migration, cell invasion, formation of stress fibre in vitro and development of liver and lung metastases in vivo. MiR-885-5p induced metastatic potential of CRC by repressing cytoplasmic polyadenylation element binding protein 2 transcription through directly binding to two binding sites on its 3' untranslated region, and consequently led to up-regulation of TWIST1 and hence epithelial-mesenchymal transition. Our findings demonstrated the overexpression of miR-885-5p in liver metastasis and its roles in inducing CRC metastasis, potentiating development of miR-885-5p inhibitor to treat advanced CRC in the future.

Emergence of CD26+ Cancer Stem Cells with Metastatic Properties in Colorectal Carcinogenesis.

Colorectal cancer results from genetic aberrations which accumulate over a long period of time, with malignant and metastatic properties acquired at a relatively late stage. A subpopulation of CD26+ colorectal cancer stem cells are known to be implicated in metastasis. We quantified CD26+ cancer cells in 11 primary tumor samples by flow cytometry, and showed that tumors having confirmed or suspected metastases harbored a relatively high CD26+ level in these samples. We hypothesized that this subpopulation of cancer stem cells arises in the late stage of carcinogenesis from the bulk of tumor daughter cells which are CD26-. The manipulation of PIK3CA and TP53, two genes commonly deregulated in the late stage, had an effect on the maintenance of the CD26+ cell population. When CD26- tumor daughter cells were sorted and cultured, the emergence of tumor spheres containing CD26+ cells occurred. These findings shed light to the origin of colorectal cancer stem cells with metastatic properties, which has an implication on conventional treatments by surgery or adjuvant chemotherapy for tumor debulking.

Identification of serum miR-139-3p as a non-invasive biomarker for colorectal cancer.

Aberrant levels of circulating microRNAs are potential biomarkers for the early detection of colorectal cancer. The aim of this study was to study miR-139-3p and miR-622 in serum as a non-invasive biomarker for colorectal cancer diagnosis. We applied quantitative polymerase chain reaction to determine the levels of miR-139-3p and miR-622 in 42 pairs of tumor and adjacent non-tumor tissues, and in serum samples of 117 patients and 90 control subjects. Our results showed that miR-139-3p was silenced whereas miR-622 was overexpressed in colorectal cancer. Similarly, serum miR-139-3p level was significantly lower in colorectal cancer patients than in control subjects whereas miR-622 was more frequently detectable in patients. ROC analysis showed that AUC of miR-139-3p was 0.9935, with a sensitivity of 96.6% and specificity of 97.8%. Serum miR-139-3p level showed high sensitivity and specificity for both early and late stage CRCs and proximal and distal CRCs. Detectable serum miR-622 showed a sensitivity of 87.5% and specificity of 63.5% for discriminating CRC patients, but the sensitivity dropped for late stage patients (72.7%). We also included analyses of the blood CEA level for comparing the diagnostic performance of these blood-based biomarkers. The median level in CRC patients (3.6 ng/ml) was significantly higher than that in control (1.8 ng/ml). The AUC value of CEA in diagnosing CRC patients was 0.7515. CEA showed a positive correlation with tumor stage and age of patients and its level was higher in male. Collectively, serum miR-139-3p has strong potential as a promising non-invasive biomarker in colorectal cancer detection.

Nine-year experience of doxorubicin-eluting beads chemoembolization for hepatocellular carcinoma.

BACKGROUND: Chemoembolization with doxorubucin-eluting beads (DEB) has been used to treat hepatocellular carcinoma (HCC) since 2007. This study compared the efficacy and survival between transarterial chemoembolization (TACE) with DEB and conventional approach (cTACE) in HCC treatment. METHODS: This retrospective case-control study compared the overall survival and tumor response of HCC patients to cTACE (n=190) and DEB (n=143) by the reassessment of computed tomography and serum alpha-fetoprotein (AFP). Multivariate analysis was used to determine the factors affecting tumor response. RESULTS: The median post-treatment to pre-treatment AFP level was 0.8 for a DEB session (n=258) and 1.0 for a cTACE session (n=452), showing a significantly greater decrease in AFP after DEB (P<0.05). More patients in the DEB group achieved objective response (complete and partial) compared with those in the cTACE group (P<0.05). Objective tumor response after DEB vs cTACE was 34.8% vs 15.4% in 0-3 months (P=0.001), 37.1% vs 20.0% in 3-6 months (P<0.05), and 50.0% vs 30.0% in 6-12 months (P=0.093). DEB predicted a 3.604 times odds of achieving at least one objective tumor response in a patient when compared to cTACE (P<0.0001). The median survival from first transcatheter therapy of patients having undergone at least once DEB was 12.53 months, while those having received cTACE only was 10.53 months (P=0.086). A tendency of improved survival appeared to maintain until >80 months after the first TACE session in the DEB group. CONCLUSION: DEB is a safe alternative to cTACE in HCC patients with better therapeutic efficacy.

A preclinical study on the combination therapy of everolimus and transarterial chemoembolization in hepatocellular carcinoma.

Transarterial chemoembolization (TACE) is commonly used for the treatment of locally advanced hepatocellular carcinoma (HCC) by its dual effects of chemotherapy and ischemic hypoxia. However, one of the side effects of TACE is the introduction of hypoxic condition, which in turn activates hypoxia-induced survival pathways and enhances VEGF-induced neovascularization by stabilizing HIF-1α expression. Herein, the preclinical therapeutic efficacy of the combined treatment of everolimus, a novel mTOR inhibitor and TACE for the treatment of HCC was investigated. The MHCC-97L cells were used for the study of the effect of combined treatment on cell proliferation and cellular apoptosis. HUVEC cells were used for the study on tube formation under different treatments. Inhibitions on the Akt/mTOR pathways were also studied. Finally, the effect on tumor growth was further study using an in vivo orthotopic model. The results demonstrated that everolimus enhanced the therapeutic efficacy of TACE in inhibiting cell proliferation, promoting apoptosis and inhibiting tube formation of endothelial cells by blocking the Akt/mTOR signaling pathway in vitro and inhibiting tumor growth and neoangiogenesis in vivo. Based on this preclinical study, the potential of combining everolimus with TACE was guaranteed which suggested the use of the combination therapy in the clinical treatment of advanced HCC patients.

Osteopontin Overexpression Induced Tumor Progression and Chemoresistance to Oxaliplatin through Induction of Stem-Like Properties in Human Colorectal Cancer.

Colorectal cancer (CRC) is one of the most common and fatal malignancies worldwide. The poor prognosis of colorectal cancer patients is due to development of chemoresistance and cancer metastasis. Recently osteopontin (OPN) has been associated with stem-like properties in colorectal cancer. This study further examined the clinicopathological significance of OPN in CRC and its effect on chemoresistance and transcription of stem cell markers. We examined the transcription level of OPN in 84 CRC patients and correlated the expression with their clinicopathological parameters. The associations of OPN overexpression with transcription of stem cell markers and response to chemotherapy in DLD1-OPN overexpressing clones and CRC patients were also investigated. Our results showed that OPN was significantly overexpressed in CRC, and its overexpression correlated with tumor stage and poor prognosis. Overexpression of CRC induced OCT4 and SOX2 expression in vitro and correlated with SOX2 overexpression in CRC patients. In addition, DLD1-OPN overexpressing cells showed enhanced ability to survive upon oxaliplatin treatment, and OPN expression was higher in CRC patients who were resistant to oxaliplatin-involved chemotherapy treatment. Thus, CRC cells overexpressing OPN demonstrated stem-like properties and OPN inhibition is a potential therapeutic approach to combat CRC progression and chemoresistance.

Post-operative plasma osteopontin predicts distant metastasis in human colorectal cancer.

BACKGROUND: The overall prognosis of colorectal cancer (CRC) patients is unsatisfactory due to cancer metastasis after operation. This study aims to investigate the clinical significance of plasma osteopontin (OPN) levels as minimally invasive, predictive, and surrogate biomarkers for prognosis of CRC patients. METHODS: This randomized study design consists of pre-operative and post-operative plasma samples from a total of 79 patients. We determined plasma levels of OPN by ELISA and examined their correlation with the clinicopathological parameters of CRC patients. The effects of endogenous and exogenous OPN on CRC metastasis were investigated by examination of the effect on regulators of epithelial to messenchymal transition and migration assay. RESULTS: Our findings demonstrated for the first time the clinical correlation of plasma OPN with metastasis of CRC patients. High post-operative plasma OPN level (>153.02 ng/ml) associated with development of metastasis after curative resection (p<0.001). Moreover, post-operative plasma OPN level correlated with disease-free survival of CRC patients (p=0.009) and was an independent factor for predicting development of metastasis in CRC patients after curative resection (p=0.036). Our in vitro model showed that OPN ectopic expression induced DLD1 cell migration through Snail and Twist1 overexpression and E-cadherin repression, and secretory OPN level enhanced cell migration. CONCLUSIONS: The results of the current study suggest that post-operative plasma OPN correlated with post-operative metastasis, suggesting that it is a potential non-invasive biomarker for the development of future metastasis in CRC patients. In addition, OPN was shown to be involved in the metastatic process and thus inhibition of OPN is a potential therapeutic approach to treat CRC patients.

Preclinical analysis of the anti-tumor and anti-metastatic effects of Raf265 on colon cancer cells and CD26(+) cancer stem cells in colorectal carcinoma.

BACKGROUND: In colorectal carcinoma (CRC), activation of the Raf/MEK/ERK signaling pathway is commonly observed. In addition, the commonly used 5FU-based chemotherapy in patients with metastatic CRC was found to enrich a subpopulation of CD26(+) cancer stem cells (CSCs). As activation of the Raf/MEK/ERK signaling pathway was also found in the CD26(+) CSCs and therefore, we hypothesized that an ATP-competitive pan-Raf inhibitor, Raf265, is effective in eliminating the cancer cells and the CD26(+) CSCs in CRC patients. METHODS: HT29 and HCT116 cells were treated with various concentrations of Raf265 to study the anti-proliferative and apoptotic effects of Raf265. Anti-tumor effect was also demonstrated using a xenograft model. Cells were also treated with Raf265 in combination with 5FU to demonstrate the anti-migratory and invasive effects by targeting on the CD26(+) CSCs and the anti-metastatic effect of the combined treatment was shown in an orthotopic CRC model. RESULTS: Raf265 was found to be highly effective in inhibiting cell proliferation and tumor growth through the inhibition of the RAF/MEK/ERK signaling pathway. In addition, anti-migratory and invasive effect was found with Raf265 treatment in combination with 5FU by targeting on the CD26(+) cells. Finally, the anti-tumor and anti-metastatic effect of Raf265 in combination with 5FU was also demonstrated. CONCLUSIONS: This preclinical study demonstrates the anti-tumor and anti-metastatic activity of Raf265 in CRC, providing the basis for exploiting its potential use and combination therapy with 5FU in the clinical treatment of CRC.

Preliminary efficacy, safety, pharmacokinetics, pharmacodynamics and quality of life study of pegylated recombinant human arginase 1 in patients with advanced hepatocellular carcinoma.

This study was designed to evaluate the efficacy, safety profile, pharmacokinetics, pharmacodynamics and quality of life of pegylated recombinant human arginase 1 (Peg-rhAgr1) in patients with advanced hepatocellular carcinoma (HCC). Patients were given weekly doses of Peg-rhAgr1 (1600 U/kg). Tumour response was assessed every 8 weeks using RECIST 1.1 and modified RECIST criteria. A total of 20 patients were recruited, of whom 15 were deemed evaluable for treatment efficacy. Eighteen patients (90%) were hepatitis B carriers. Median age was 61.5 (range 30-75). Overall disease control rate was 13%, with 2 of the 15 patients achieving stable disease for >8 weeks. The median progression-free survival (PFS) was 1.7 (95% CI: 1.67-1.73) months, with median overall survival (OS) of all 20 enrolled patients being 5.2 (95% CI: 3.3-12.0) months. PFS was significantly prolonged in patients with adequate arginine depletion (ADD) >2 months versus those who had ≤2 months of ADD (6.4 versus 1.7 months; p = 0.01). The majority of adverse events (AEs) were grade 1/2 non-hematological toxicities. Transient liver dysfunctions (25%) were the most commonly reported serious AEs and likely due to disease progression. Pharmacokinetic and pharmacodynamic data showed that Peg-rhAgr1 induced rapid and sustained arginine depletion. The overall quality of life of the enrolled patients was well preserved. Peg-rhAgr1 is well tolerated with a good toxicity profile in patients with advanced HCC. A weekly dose of 1600 U/kg is sufficient to induce ADD. Significantly longer PFS times were recorded for patients who had ADD for >2 months.

Advanced pancreatic cancer: flourishing novel approaches in the era of biological therapy.

The progress in the development of systemic treatment for advanced pancreatic cancer (APC) has been slow. The mainstream treatment remains using chemotherapy including gemcitabine, FOLFIRINOX, and nab-paclitaxel. Erlotinib is the only approved biological therapy with marginal benefit. Studies of agents targeting epidermal growth factor receptor, angiogenesis, and RAS signaling have not been satisfying, and the usefulness of targeted therapy in APC is uncertain. Understanding in molecular processes and tumor biology has opened the door for new treatment strategies such as targeting insulin-like growth factor 1 receptor, transforming growth factor ß, phosphoinositide 3-kinase/AKT/mammalian target of rapamycin pathway, and Notch pathway. New directions also include the upcoming immunotherapy and many novel agents that act on the microenvironment. The practice of personalized medicine using predictive biomarkers and pharmacogenomics signatures may also enhance the effectiveness of existing treatment. Future treatment approaches may involve comprehensive genomic assessment of tumor and integrated combinations of multiple agents to overcome treatment resistance.

The clinicopathological significance of miR-133a in colorectal cancer.

This study determined the expression of microRNA-133a (MiR-133a) in colorectal cancer (CRC) and adjacent normal mucosa samples and evaluated its clinicopathological role in CRC. The expression of miR-133a in 125 pairs of tissue samples was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) and correlated with patient's clinicopathological data by statistical analysis. Endogenous expression levels of several potential target genes were determined by qRT-PCR and correlated using Pearson's method. MiR-133a was downregulated in 83.2% of tumors compared to normal mucosal tissue. Higher miR-133a expression in tumor tissues was associated with development of distant metastasis, advanced Dukes and TNM staging, and poor survival. The unfavorable prognosis of higher miR-133a expression was accompanied by dysregulation of potential miR-133a target genes, LIM and SH3 domain protein 1 (LASP1), Caveolin-1 (CAV1), and Fascin-1 (FSCN1). LASP1 was found to possess a negative correlation (γ = -0.23), whereas CAV1 exhibited a significant positive correlation (γ = 0.27), and a stronger correlation was found in patients who developed distant metastases (γ = 0.42). In addition, a negative correlation of FSCN1 was only found in nonmetastatic patients. In conclusion, miR-133a was downregulated in CRC tissues, but its higher expression correlated with adverse clinical characteristics and poor prognosis.

Plasma Bmi1 mRNA as a potential prognostic biomarker for distant metastasis in colorectal cancer patients.

Bmi1 is overexpressed in gastrointestinal cancers, including colorectal cancer (CRC); however, its role as a non-invasive biomarker in CRC has not been established. The aim of this study was to compare the plasma Bmi1 mRNA levels prior to and following curative resection of the primary tumor in CRC patients and to determine their association with the clinicopathological parameters. The plasma Bmi1 mRNA level was measured by quantitative polymerase chain reaction and expressed as cycle threshold value. There was no significant difference between the overall pre- and postoperative plasma Bmi1 mRNA level (31.73±2.63 vs. 31.93±2.88, respectively; P=0.614) in 45 CRC patients. However, when grouped into non-metastatic and metastatic CRC patients, the postoperative Bmi1 transcript level was found to be significantly lower compared to the preoperative level in patients with non-metastatic CRC (32.13±2.677 31.44±2.764, respectively; P=0.041), whereas there was a trend towards a higher postoperative Bmi1 transcript level compared to the preoperative level in the metastatic counterpart (30.85±3.916 vs. 33.27±0.718, respectively; P=0.164). Furthermore, when the patients were categorized into two groups according to their plasma Bmi1 postoperative vs. preoperative level status, we observed that patients without a reduction in the postoperative plasma Bmi1 mRNA levels exhibited a significantly higher rate of distant metastasis following primary resection (P=0.017) and a significantly worse prognosis regarding disease-free survival (P=0.016) when compared to the reduced postoperative plasma Bmi1 level counterparts. In conclusion, plasma Bmi1 mRNA levels may serve as a non-invasive biomarker for monitoring occult metastasis and predicting the development of distant metastasis.

Survivin depletion inhibits tumor growth and enhances chemosensitivity in hepatocellular carcinoma.

Survivin is a member of the inhibitor of apoptosis family, which has been suggested to be crucial in the control of cell division and inhibition of apoptosis. Expression of this protein has been observed in transformed cell lines and human tumor tissues, including those from colorectal cancer, but not in terminally differentiated adult tissues. Survivin mRNA expression has frequently been detected in hepatocellular carcinoma (HCC) and its protein expression has been demonstrated to be highly correlated with proliferation index rather than apoptotic index. The present study aimed to analyze the effect of survivin on the tumorigenicity and chemosensitivity of HCC via the establishment of an HCC cell line (PLC/PRF/5) with the stable knockdown of the survivin gene (PLC­k3). This cell line displayed significantly lower rates of survival and proliferation in assays of cell viability and proliferation, respectively, compared with those of the control cell line (PLC­v). In addition, PLC­k3 cells were more sensitive to cisplatin treatment, resulting in S phase arrest. These findings were further confirmed by an in vivo experiment. The data of the present study suggest that survivin is critical in promoting cell proliferation but not in inhibition of apoptosis, and enhances the chemosensitivity of HCC. Thus, the suppression of survivin expression in combination with cisplatin may contribute to the development of more effective treatments for HCC.