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Severe malnutrition accompanied by sarcopenia and cachexia, is strongly associated with the surgical and oncological outcomes in cancer patients. The aim of the present study was to clarify the clinical significance of sarcopenia and its correlation with sarcopenia-associated miRNA in colorectal cancer (CRC). A total of 167 CRC patients were enrolled in the present study. We evaluated psoas muscle mass index (PMI) and intramuscular adipose tissue content (IMAC). The expression of miR-21 in CRC tissues and preoperative serum was evaluated using quantitative PCR. Despite the lack of significant correlation between IMAC and disease-correlated factors, decreased PMI was significantly associated with well-established clinicopathological factors for disease progression. Decreased PMI was an independent prognostic factor for both overall survival and disease-free survival and was an independent risk factor for various types of metastasis. In contrast to the expression of tissue miR-21, the expression of serum miR-21 was significantly increased in CRC patients with low PMI. Furthermore, postoperative PMI was drastically improved compared with preoperative PMI in CRC patients with potentially curative resections. In conclusion, skeletal muscle mass may be a prognostic and predictive biomarker for distant metastasis in CRC patients and quantification of serum miR-21 expression could help clinicians make decisions regarding nutrition intervention strategies in CRC patients.

Cancer research is currently focused on blocking the metastatic process at its early steps. Some particularly attractive targets are metastasis suppressor genes, which control cancer cell dissemination. The aim of this study was to clarify the relationship between the expression of KiSS1, a metastasis suppressor gene, and disease progression in colorectal cancer patients. One-hundred and seventy-five patients who underwent surgery for colorectal cancer were enrolled in this study. We analyzed KiSS1 mRNA expression by real-time reverse transcription PCR in colorectal cancer tissue and paired adjacent normal mucosa. KiSS1 protein expression in early- and advanced-stage colorectal cancer samples was determined by immunohistochemical analysis. Decreased KiSS1 expression was significantly associated with lymph node metastasis and was an independent prognostic factor. Logistic regression analysis revealed that decreased KiSS1 expression was an independent risk factor for lymph node metastasis. Immunohistochemical analysis indicated that KiSS1 was highly expressed in the cell cytoplasm of early-stage colorectal cancer cells. The loss of KiSS1 appears to correlate with the progression of lymph node metastasis. An assessment of KiSS1 expression may assist in the accurate colorectal cancer diagnosis and may contribute to predict clinical outcomes.

The metastasis-associated (MTA) gene family is a critical component of the nucleosome remodeling and histone deacetylase complex, and plays an important role in metastatic processes. We systematically evaluated dysregulation of the MTA family to clarify their clinical significance in gastric cancer (GC). One hundred and forty-five patients who underwent surgery for GC were evaluated. We analyzed the expression levels of the MTA family (MTA1, 2 and 3) by qPCR in GC tissue, and the MTA1 protein expression in primary cancer and matched normal mucosa (NM) was measured using immunohistochemical analysis. The expression of all the MTA family members was significantly increased in a stage-dependent manner, and elevated expression of all of the MTA family members was correlated with metastatic factors and prognosis in GC patients. Multivariate analysis revealed that MTA1 overexpression was an independent risk factor for survival. Especially, elevated expression of MTA1 was significantly correlated with recurrence, and was an independent risk factor for lymph node metastasis. Immunohistochemical analysis demonstrated that MTA1 was predominantly expressed in the nuclei of primary GC cells but was not expressed in NM and in the cancer stroma. In conclusion, quantification of MTA expression may support the accurate diagnosis of disease staging and may help predict clinical outcomes.

In vivo real-time visualization of chemotherapy response at the cellular level provides us with direct evidence of what happens on the tumor microenvironment of metastatic organs. We imaged the response of metastatic tumor cells and host stromal cells to chemotherapeutics on liver metastatic xenografts in living mice using intravital two-photon laser scanning microscopy (TPLSM). Red fluorescent protein-expressing human colorectal cancer cells (HT29) was inoculated to the spleen of green fluorescent protein-expressing nude mice. 5-Fluorouracil or irinotecan was intraperitoneally administered after the formation of macroscopic liver metastases. Intravital TPLSM was performed at multiple time-points for time-series imaging of liver metastatic xenografts in the same mice. Under the 1st TPLSM, HT29 cells were visualized in hepatic sinusoids at the single cell level. Liver metastatic nodules consisting of viable cancer cells and surrounding stroma with tumor vessels were visualized under the 2nd TPLSM. After chemotherapy, tumor cell fragmentation, condensation, swelling and intracellular vacuoles were observed under the 3rd TPLSM. There was no obvious morphological difference in tumor response between these chemotherapeutics. Time-series intravital TPLSM imaging on the metastatic tumor xenografts may be useful for screening and evaluating new chemotherapeutics with less interindividual variability.

Our aim was to evaluate the KRAS genotypes of Japanese colorectal cancer (CRC) patients and to assess the effect of these genotypes on clinical outcome. A total of 99 patients with stage I-IV CRC who underwent resection were prospectively studied for KRAS mutations by direct sequencing. KRAS mutations were found in 37 (37.4%) of 99 patients. Of these, 11.1% were the KRAS p.G13D mutation and the remaining 26.2% were other KRAS mutations. The cumulative 5-year survival rates for patients with wild-type KRAS, KRAS 12 and KRAS p.G13D mutations were 81.4, 61.4 and 42.0%, respectively (P=0.0397). The KRAS genotype had no effect on stage IV patient prognosis without anti-epithelial growth factor receptor (EGFR) antibody therapy. However, in stage I-III patients significant or trends in prognostic factors for disease-free survival (DFS) were pathological T stage, lymphatic vessel involvement and KRAS p.G13D. Multivariate analysis identified T4 pathological stage (P=0.0076) and the KRAS p.G13D mutation (P=0.0499) as the most significant independent prognostic factors associated with DFS. In Japanese CRC patients KRAS p.G13D had prognostic impact on DFS in stage I-III disease, while the prognosis of stage IV patients without anti-EGFR antibody therapy was unaffected by KRAS status.

Tumor regression grading (TRG) reportedly has prognostic value in rectal cancer patients after pre-operative chemoradiotherapy (CRT). The aim of this retrospective study was to differentiate gene expression profiles based on TRG in residual cancer cells after CRT. We evaluated pathological response using the criteria of four TRG systems: the Japanese Society for the Cancer of Colon and Rectum (JSCCR), Mandard, Dworak and Rodel. Total RNA was obtained using microdissection from 52 locally advanced rectal cancer specimens from patients who underwent pre-operative CRT to examine the expression levels of 20 genes [PCNA, MKI67, CDKN1A (p21Cip1), CDK2, CHEK1, PDRG1, LGR5, PROM1 (CD133), CD44, SOX2, POU5F1 (OCT4), LKB1, VEGF, EGFR, HGF, MET, HIF1, GLUT1, BAX and BCL2] using real-time quantitative RT-PCR. Gene expression was compared across the four TRG systems. LGR5 gene expression levels in CRT non-responders were significantly higher than in responders in all four grading systems. Patients with elevated PDRG1 and GLUT1 gene expression had poor pathological response in three TRG systems (JSCCR, Dworak and Rodel). MKI67 gene expression in non-responders was significantly higher than in responders in two grading systems (JSCCR and Rodel). While, BAX gene expression in responders was significantly higher than in non-responders in the Mandard TRG system. The results of this study suggest that TRG may reflect characteristics, such as proliferative activity, stemness potency and resistance to hypoxia, of residual cancer cells following pre-operative CRT.

Neoadjuvant chemo-radiotherapy (CRT) followed by surgery are the standard approaches for locally advanced esophageal cancer. However, the overall cure rate is very low. The aim of this preliminary study was to evaluate the expression of podoplanin and SOX2 known as stemness markers for esophageal squamous cell carcinoma (ESCC) and their association with clinical outcome. We obtained a total of 20 specimens from patients with ESCC who underwent neoadjuvant CRT (30-40 Gy; 5-fluorouracil plus cisplatin) followed by surgery. Podoplanin and SOX2 expression was evaluated using immunohistochemistry and the association of their expressions with clinicopathological variables was investigated. Podoplanin and SOX2 staining was detected not only in residual cancer cells, but also in the basal layer of adjacent normal mucosa after neoadjuvant CRT. High expression of podoplanin was correlated with lymph node metastasis, advanced postoperative stage and vascular invasion (P

Radiotherapy remains a major approach to adjuvant therapy for patients with advanced rectal cancer. Nevertheless, the effects of radiation on malignant processes have yet to be clarified. The aim of this study was to assess the biological effects of radiation on colorectal cancer (CRC) cells with special reference to epithelial-mesenchymal transition (EMT), a key developmental program often activated during cancer invasion and metastasis. We investigated the effect of radiation on two colorectal cancer cell lines, CaR1 and DLD1, assessing cell morphology, motility, migration and invasive ability. Expression of molecules associated with EMT was determined using RT-PCR, Western blotting, and immunofluorescence staining in control and irradiated cells. We also used real-time RT-PCR to examine the expression of molecules associated with EMT before and after chemoradiotherapy. Thus, we studied 26 rectal cancer patients who received preoperative chemoradiotherapy followed by radical surgery. In addition, we examined the relationship between disease recurrence and the expression of a number of proteins. Irradiation caused CRC cells to undergo phenotypic changes characteristic of EMT: spindle-cell shape, loss of polarity, intercellular separation and pseudopodia formation. Irradiation enhanced cell migration and invasiveness. In irradiated CRC cells, molecular changes consistent with EMT were observed. In clinical samples, we observed molecular changes consistent with EMT, and those changes were significantly enhanced in patients with recurring disease. These results indicate that irradiation induces an alteration to a malignant phenotype consistent with EMT in colorectal cancer cells.

To evaluate the feasibility of paclitaxel (PTX) radiosensitization for colon cancer, we investigated the cytotoxic and G2/M checkpoint protein (Chk1, Wee1, Bub1, MAD2) effects of 5-fluorouracil (5-FU) or PTX combined with radiation in the human colon cancer cell line LoVo. Cytotoxicity and radiocytotoxicity were evaluated for each drug by the WST-8 colorimetric assay. The IC20 for each drug was determined as a cytotoxic concentration from a survival curve. LoVo cells were exposed to the IC20 of each drug for 24 h and then irradiated. Expressions of the G2/M checkpoint proteins were confirmed by Western blot analysis. Cytotoxicity was induced by 5-FU or PTX alone in a time- and dose-dependent manner. The IC20 of PTX caused higher radiosensitivity than the IC20 of 5-FU (P

CD133 has been described as a marker for cancer stem cells (CSCs) in colorectal cancer. Additionally, it has been reported that CSCs are resistant to chemoradiotherapy (CRT). After previously observing that CD133 mRNA levels were elevated after CRT in rectal cancer patients, we further investigated CD133 expression in colorectal cancer following CRT using immunohistochemistry. Forty patients with primary colorectal cancers and 50 patients with rectal cancer who had received preoperative CRT followed by surgery were selected. Sections of formalin-fixed, paraffin-embedded specimens were stained for CD133, CK20 and Ki-67. To clarify the change of CD133 protein after irradiation, CD133 protein levels were examined in radiation-treated human colon cancer cell line HT29. We found four distinct patterns of CD133 staining defined by CD133 expression in luminal surface, in intraluminal cells and in cytoplasm. In total, CD133 expression was detected in 27.5% of non-CRT and 70% of CRT specimens. The frequency of CD133 staining in CRT specimens was significantly higher than that of non-CRT specimens. Seven out of 50 CRT specimens exhibited cytoplasmic staining. These cells with cytoplasmic CD133 expression did not express CK20 or Ki-67. The ratio of histopathological responder in cases with CD133 expression in both luminal surface and cytoplasm was significantly lower than that without it (P

CD133 has been postulated to be a colon cancer stem cell (CSCs) marker. Recent investigations suggest that CSCs might contribute to cancer recurrence and resistance to conventional therapies. This study aimed to evaluate the role of CD133 in residual cancer cells after chemoradiotherapy (CRT) for rectal cancer. Forty patients with rectal cancer underwent CRT followed by surgery. Total RNAs of rectal cancer cells before (n=30) and after (n=40) CRT were isolated. Intratumoral CD133, vascular endothelial growth factor (VEGF), and epidermal growth factor receptor (EGFR) levels were measured using real-time reverse transcription polymerase chain reaction. Immunohistochemical staining of CD133 after CRT was also investigated. CD133 in residual cancer cells was higher than in stromal cells in post-CRT specimens (p

This study was undertaken to evaluate long-term results of radiofrequency (RF) ablation in patients with colorectal lung metastases and to stratify patients benefitting from lung RF ablation. Lung RF ablation was performed in 78 patients with 198 colorectal lung metastases. Safety, local tumor progression, and survival were evaluated retrospectively. The mean follow-up period after the 140 lung RF ablation sessions was 24.6+/-7.6 months. Pneumothorax and pleural effusion requiring chest tube placement occurred respectively in 18 (12.9%, 18/140) and 2 (1.4%, 2/140) sessions. The respective 1-, 3- and 5-year local tumor progression rates were 10.1% (95% CI, 2.9-17.3%), 20.6% (95% CI, 8.9-22.2%) and 20.6% (95% CI, 8.9-22.2%). The 1-, 3- and 5-year survival rates were 83.9% (95% CI, 75.2-92.7%), 56.1% (95% CI, 41.7-70.5%) and 34.9% (95% CI, 18.0-51.9%), with median survival time of 38.0 months. Univariate analysis revealed maximum tumor diameter of 3 cm or less, single-lung metastasis, lack of extrapulmonary metastasis and normal carcinoembryonic antigen (CEA) level as better prognostic factors. The latter two were significant independent prognostic factors. The 1-, 3- and 5-year survival rates were 97.7% (95% CI, 93.3-100%), 82.5% (95% CI, 68.2-96.8%) and 57.0% (95% CI, 34.7-79.2%) in 54 patients with no extrapulmonary metastases and 96.9% (95% CI, 90.8-100%), 86.1% (95% CI, 71.1-100%) and 62.5% (95% CI, 36.3-88.6%) in 33 patients with negative CEA levels. Lung RF ablation is a safe and useful therapeutic option. These identified prognostic factors will help to stratify patients who benefit from lung RF ablation.

Microdissection is a reliable technique and is extensively used in many cancer studies. We sought to verify the importance of the microdissection technique in molecular analysis of irradiated rectal cancer specimens. Forty patients with rectal cancer underwent 5-fluorouracil based chemoradiotherapy followed by curative surgery. We compared gene expressions that had previously been shown to be involved in chemotherapy or radiation effects; one obtained using RNA extracted from cancer cells by microdissection, and the other from bulky cancer tissues in all patients. More than 50% regression of the primary tumor was seen in 16 patients (40.0%). There was no significant difference in candidate gene expression profiles between tumor and stromal cells except for thymidine phosphorylase (TP). Without microdissection, there was no significant association between distant recurrence and gene expression in specimens. With microdissected sample analysis, however, patients who developed distant recurrence were found to have significantly higher intratumoral thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD) and orotate phosphoribosyl transferase (OPRT) compared with patients without recurrence. It is possible that microdissection is essential for gene expression analysis of clinically irradiated rectal specimens because preoperative chemoradiotherapy for rectal cancer affects the tumor-stroma balance in irradiated rectal cancer specimen.

Chemotherapy remains the main choice of treatment for the management of unresectable or metastatic colorectal cancer. However, drug resistance is a major problem, limiting the effectiveness of the chemotherapies presently used to treat cancer. During treatment, drug resistance can also be acquired by tumors that are initially sensitive to chemotherapy. We present a case of metachronous splenic recurrence after a curative resection of appendical cancer with ovarian metastasis, although the patient had been treated with 5-FU/LV followed by mFOLFOX6 after surgery. Molecular analyses by RT-PCR also showed that the residual tumor after chemotherapy has cancer cells overexpressing 5-FU/l-OHP based chemotherapy-resistant genes. Therefore, it was suggested that a careful assessment of the disease status be undertaken during chemotherapy to ensure that the possibility of surgical resection, especially of the re-growth or partial response tumors, was not missed, since several genes, chemoresistant to the agents used, can be induced in residual tumors during chemotherapy.

To assess whether preoperative chemo-radiotherapy enhances the expression of vascular endothelial growth factor (VEGF) in patients with colorectal cancer, we investigated in vivo and in vitro the interactions between chemo-radiotherapy and the expression of VEGF, and their possible impact on distant metastasis. Cellular cytotoxicity in the colon cancer cell lines, LoVo, SW480 and Caco2, was determined using a WST-8 colorimetric assay after cells were exposed to 5-fluorouracil combined with radiation. In addition, the VEGF levels in cultured cells were measured by ELISA. Preoperative serum samples and tumor specimens were prospectively collected from 32 rectal cancer patients who received preoperative chemo-radiotherapy. Both local and circulating VEGF expression levels were measured perioperatively by ELISA, and assessed in relation to the clinicopathological findings. Perioperative circulating VEGF levels from irradiated patients were also compared with a non-irradiated control group. There were significant increases in local VEGF levels, both in vivo and in vitro, after chemo-radiotherapy, especially in viable cancer cells. The circulating VEGF levels in the irradiated patients were significantly lower after surgery compared with those in the control group. Although preoperative chemo-radiotherapy enhanced tumor-specific VEGF expression, especially in individual cancer cells both in vitro and in vivo, it did not necessarily enhance systemic VEGF expression, possibly because of tumor volume reduction induced by the chemo-radiotherapy.

To evaluate the optimal schedule of 5-fluorouracil (5-FU) radiosensitization in rectal cancer, we investigated the interaction between radiation and several doses of 5-FU on colon cancer cell lines based on pharmacokinetics of oral fluoropyrimidine. Cellular cytotoxicity in colon cancer cell lines, LoVo, WiDr and Caco-2 was determined, using a WST-8 colorimetric assay, after 24 h exposure to several concentrations of 5-FU and a radiation dose of 5 Gy. Cells were exposed to 5-FU 24 and 0 h before radiation. 5-FU doses were classified into three groups: uracil-tegafur (0.01-0.1 microM), S-1 (0.1-1.0 microM) and pharmacokinetic modulating chemotherapy (0.1-10 microM). In addition, the effect of 5-FU on the steady-state levels of a human excision repair cross-complementing 1 gene and cell cycle distribution were examined. Regardless of time of 5-FU exposure, all cell growth was significantly inhibited in a dose-dependent manner. In Caco-2 cells, the cytotoxicity of radiation followed by 5-FU was significantly greater than that of 5-FU followed by radiation, unlike in the other cell lines. The growth inhibitory effect of radiation followed by 5-FU increased in a dose-dependent manner to reach a plateau at S-1 doses in all cell lines. In cell cycle distribution, 5-FU exposure for 24 h increased the S phase fraction in a dose-dependent manner. RT-PCR showed that 5-FU post-treatment graduallly inhibited mRNA expression of ERCC1, which may affect recombination repair efficiency, accounting for the higher tumor sensitivity. Oral fluoropyrimidines, like S-1, that can maintain a constant level of 5-FU may be an acceptable alternative radiosensitizer to protracted 5-FU infusion, when the aim of neoadjuvant chemoradiotherapy for rectal cancer is locoregional control.

This retrospective study was conducted to assess the safety, efficacy, and long-term results of multi-modality therapy including radio-frequency thermal ablation (RFA) and radiotherapy as an additional cytoreductive method for eliciting the marked effects of chemotherapy in treating unresectable lung metastases from colorectal cancer. Total of 21 patients with lung metastasis from colorectal cancer were included. They were treated with modified pharmacokinetic modulating chemotherapy (PMC). Eleven were also treated with RFA and/or radiotherapy (multi-modality group), and 10 were treated with chemotherapy alone (chemotherapy group). Characteristics and survival of patients in the multi-modality group were compared with those of the chemotherapy group. The median survival of all patients was 38.6 months after the initial PMC. The cumulative 3-year survival rate of patients in the multi-modality group was 87.5% compared with 33.3% in the chemotherapy group (p=0.0041). The course of multi-modality therapy was uneventful except for pneumothorax in those who received RFA. Although pneumothorax developed in 4 of 11 patients (36.4%) treated with RFA, all were able to receive chemotherapy within 2 weeks after RFA. In conclusion, multi-modality therapy combined with modified PMC, radiation and RFA is a feasible choice of treatment associated with reasonable morbidity and mortality in patients with inoperable lung metastases from colorectal cancer.