RHBDD2 overexpression promotes a chemoresistant and invasive phenotype to rectal cancer tumors via modulating UPR and focal adhesion genes.

The current standard of care for locally advanced rectal cancer (RC) is neoadjuvant radio-chemotherapy (NRC) with 5-fluorouracil (5Fu) as the main drug, followed by surgery and adjuvant chemotherapy. While a group of patients will achieve a pathological complete response, a significant percentage will not respond to the treatment. The Unfolding Protein Response (UPR) pathway is generally activated in tumors and results in resistance to radio-chemotherapy. We previously showed that RHBDD2 gene is overexpressed in the advanced stages of colorectal cancer (CRC) and that it could modulate the UPR pathway. Moreover, RHBDD2 expression is induced by 5Fu. In this study, we demonstrate that the overexpression of RHBDD2 in CACO2 cell line confers resistance to 5Fu, favors cell migration, adhesion and proliferation and has a profound impact on the expression of both, the UPR genes BiP, PERK and CHOP, and on the cell adhesion genes FAK and PXN. We also determined that RHBDD2 binds to BiP protein, the master UPR regulator. Finally, we confirmed that a high expression of RHBDD2 in RC tumors after NRC treatment is associated with the development of local or distant metastases. The collected evidence positions RHBDD2 as a promising prognostic biomarker to predict the response to neoadjuvant therapy in patients with RC.

ARID3A Positivity Correlated With Favorable Prognosis in Patients With Residual Rectal Cancer After Neoadjuvant Chemoradiotherapy.

BACKGROUND/AIM: Recent studies have shown a marked increase of AT-rich interactive domain 3A (ARID3A) in colon cancer tissue compared to normal colon mucosa. However, the role of ARID3A has not yet been determined in rectal cancer. We, therefore, investigated the clinical relevance of ARID3A expression in patients with residual rectal cancer after neoadjuvant chemoradiotherapy (NACRT). MATERIALS AND METHODS: One hundred thirty-four patients who underwent surgical resection for residual rectal cancer after NACRT were analyzed. ARID3A expression was evaluated using immunohistochemistry on whole-tissue sections. KRAS exon 2 (codons 12 and 13) and BRAF V600E mutation status were determined using polymerase chain reaction. RESULTS: ARID3A positivity was found in 91 cases (64.5%), and it correlated with absence of perineural invasion (p=0.031), longer disease-free survival (DFS) (p=0.048) and cancer-specific survival (CSS) (p=0.006). However, ARID3A positivity was not correlated with KRAS (p=0.231) or BRAF mutation status (p=0.577). In multivariate analysis, ARID3A positivity was independently associated with a favorable CSS (p=0.035), but not DFS (p=0.051). CONCLUSION: ARID3A positivity can predict favorable prognosis in patients with residual rectal cancer after NACRT.

Pathological complete response may underestimate distant metastasis in locally advanced rectal cancer following neoadjuvant chemoradiotherapy and radical surgery: Incidence, metastatic pattern, and risk factors.

AIM: To evaluate the pattern of tumor relapse of pathological complete response (pCR) patients with locally advanced rectal cancer (LARC) following neoadjuvant chemoradiotherapy (nCRT) and total mesorectal excision (TME), and to identify predictive factors of distant metastasis in pCR patients after nCRT. METHOD: This was a retrospective analysis of 118 LARC patients who achieved a pCR following nCRT and TME from 2008 to 2015. Clinicopathological and therapeutic parameters were evaluated as possible predictors of distant metastasis-free survival (DMFS), and COX regression analysis was performed. RESULTS: After a median follow-up of 57 months, the 5-year overall and disease-free survival rates were 94.7% and 88.1%, respectively. Overall, 6 patients (5.1%) died, no local recurrence occurred, 13 patients (11%) developed distant metastases, including lung (n = 5), liver (n = 2), bone (n = 3), lung and brain (n = 1), peritoneal (n = 1), and spleen (n = 1) metastasis. On univariate analysis, tumor distance from the anal verge (HR = 0.706, P = 0.039), acellular mucin pools (HR = 6.687, P = 0.002), and MUC1 expression (HR = 8.280, P < 0.001) were independently associated with DMFS. COX regression demonstrated that MUC1 expression (HR = 3.812, P = 0.041) remained to be an independent predictor of DMFS in pCR patients. CONCLUSION: Distant metastasis still remained a major concern in pCR patients following nCRT and TME. Tumor distance from the anal verge, acellular mucin pools, and MUC1 expression were associated with distant metastasis in patients with pCR. MUC1 staining remained to be an independent risk factor for DMFS. Such information could facilitate treatment decision in these patients, such as adjuvant chemotherapy and follow-up.

SUVmax-based Parameters of FDG-PET/CT Reliably Predict Pathologic Complete Response After Preoperative Hyperthermo-chemoradiotherapy in Rectal Cancer.

BACKGROUND/AIM: To determine the most reliable predictor for pathologic complete response (pCR) in patients who underwent preoperative chemoradiotherapy and regional hyperthermia (HCRT) for rectal cancer. PATIENTS AND METHODS: Thirty-six patients were enrolled. The local control status of the patients was assessed using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT), magnetic resonance imaging (MRI), and colonoscopy before and after HCRT. The relationships between various parameters of these clinical examinations and pCR were analyzed. RESULTS: Ten (28%) patients achieved pCR. The accuracies of predicting pCR using FDG-PET/CT, MRI, and colonoscopy were 78%, 61%, and 75%, respectively. FDG-PET/CT was the only independent predictive modality for pCR (p=0.021). The maximum standardized uptake value (SUVmax) and SUVmax normalized to liver uptake (SLR) after HCRT showed the highest sensitivity (90%) and the decreasing rate of SUVmax and SLR demonstrated the highest specificity (89%) for pCR. CONCLUSION: SUVmax-based parameters of FDG-PET/CT after HCRT were the most reliable predictors for pCR.

Relationship Between Expression of Proteins ERCC1, ERCC2, and XRCC1 and Clinical Outcomes in Patients with Rectal Cancer Treated with FOLFOX-Based Preoperative Chemoradiotherapy.

BACKGROUND: Platinum resistance enhances DNA damage repair through nucleotide excision repair mechanisms involving the excision repair cross-complementing group 1 (ERCC1), X-ray cross-complementing group 1 (XRCC1), and excision repair cross-complementing group 2 (ERCC2). We evaluated the correlation between the expression of these three DNA repair genes and clinical outcomes in patients with rectal cancer receiving FOLFOX-based preoperative chemoradiotherapy (CRT). METHODS: Using immunohistochemistry, we examined the expression of ERCC1, ERCC2, and XRCC1 in pre-CRT cancer tissues from 86 patients with rectal cancer who had undergone curative resection and preoperative CRT with FOLFOX-4 to identify potential predictors of clinical outcomes. RESULTS: Following CRT, 57 and 29 patients were classified as responders (pathological tumor regression grade TRG 0 and TRG 1) and poor responders (TRG 2 and TRG 3), respectively. The multivariate analysis revealed that ERCC1 overexpression was correlated with a poor CRT response [p < 0.0001; odds ratio (OR), 9.397; 95% confidence interval (CI) 2.721-32.457]. Furthermore, a poor response to CRT (pathological TRG of 2-3) (p = 0.18; OR 5.685; 95% CI 1.349-23.954) and abnormal pre-CRT serum carcinoembryonic antigen levels (>5 ng/mL) (p = 0.03; OR 6.288; 95% CI 1.198-33.006) were independent predictors of postoperative relapse. By contrast, ERCC2 and XRCC1 expression did not play predictive roles in the analyzed patients. CONCLUSIONS: ERCC1 overexpression is associated with a poor preoperative CRT response in patients with rectal cancer receiving FOLFOX-based preoperative CRT. ERCC1 is a potential biomarker for identifying patients who can benefit from customized treatment programs.

Transcriptomics and proteomics show that selenium affects inflammation, cytoskeleton, and cancer pathways in human rectal biopsies.

Epidemiologic studies highlight the potential role of dietary selenium (Se) in colorectal cancer prevention. Our goal was to elucidate whether expression of factors crucial for colorectal homoeostasis is affected by physiologic differences in Se status. Using transcriptomics and proteomics followed by pathway analysis, we identified pathways affected by Se status in rectal biopsies from 22 healthy adults, including 11 controls with optimal status (mean plasma Se = 1.43 µM) and 11 subjects with suboptimal status (mean plasma Se = 0.86 µM). We observed that 254 genes and 26 proteins implicated in cancer (80%), immune function and inflammatory response (40%), cell growth and proliferation (70%), cellular movement, and cell death (50%) were differentially expressed between the 2 groups. Expression of 69 genes, including selenoproteins W1 and K, which are genes involved in cytoskeleton remodelling and transcription factor NFκB signaling, correlated significantly with Se status. Integrating proteomics and transcriptomics datasets revealed reduced inflammatory and immune responses and cytoskeleton remodelling in the suboptimal Se status group. This is the first study combining omics technologies to describe the impact of differences in Se status on colorectal expression patterns, revealing that suboptimal Se status could alter inflammatory signaling and cytoskeleton in human rectal mucosa and so influence cancer risk.-Méplan, C., Johnson, I. T., Polley, A. C. J., Cockell, S., Bradburn, D. M., Commane, D. M., Arasaradnam, R. P., Mulholland, F., Zupanic, A., Mathers, J. C., Hesketh, J. Transcriptomics and proteomics show that selenium affects inflammation, cytoskeleton, and cancer pathways in human rectal biopsies.

NF-κB/p65 expression before and after treatment in rectal cancer patients undergoing neoadjuvant (chemo)radiotherapy and surgery: prognostic marker for disease progression and survival.

Nuclear factor-kappaB (NF-κB), especially p65 subunit, has been associated with origin and progression of cancer as well as with the resistance to radiotherapy and chemotherapy in experimental models. The aim of the present study was to determine expression of NF-κB/p65 in tumor specimens before and after treatment of rectal cancer patients and to evaluate possible relationship between expression of NF-κB/p65 before and after (chemo)radiotherapy, other tumor characteristics and the clinical outcome. Furthermore, NF-κB/p65 was studied in relationship to pathologic response to preoperative (chemo)radiotherapy. Fifty patients with rectal cancer undergoing neoadjuvant (chemo)radiotherapy and surgery were included in the study. Pre-treatment rectal cancer specimens were obtained from diagnostic colonoscopy. Post-treatment rectal cancer specimens were obtained from surgically removed part of the rectum with the tumor. NF-κB/p65 expression was determined by immunohistochemistry and analysis was performed both in biopsies and in post-treatment tumor samples. Cytoplasmic positivity in tumor cells and nuclear positivity in lymphocytes were detected. High NF-κB/p65 positivity in pre-treatment tumor samples was significantly associated with shortened overall survival (OS). Disease-free survival (DFS) tends to be shortened as well. In post-treatment tumor samples, high NF-κB/p65 positivity was neither associated with shortened OS nor with shortened DFS. In post-treatment samples residual tumor cells deeply infiltrating the wall of the rectum with high NF-κB/p65 expression were found. The cells were linked to significantly worse clinical outcome in terms of shortened OS and DFS. NF-κB/p65 positivity did not correlate with pathologic response to preoperative (chemo)radiotherapy. In conclusion, our data suggest that high level of NF-κB/p65 subunit may be associated with more aggressive features of the tumor, higher metastatic potential, and shortened overall survival, but it does not correlate with resistance to (chemo)radiotherapy. Consequently, the level of NF-κB/p65 may help to select those patients who have poor prognosis and are candidates for more intensive anticancer therapy. For these purposes both pre-treatment and post-treatment tumor samples may be used.

Reduced folate and serum vitamin metabolites in patients with rectal carcinoma: an open-label feasibility study of pemetrexed with folic acid and vitamin B12 supplementation.

The objectives of this single-center, open-label, phase II study were to evaluate (a) the feasibility and safety of neoadjuvant administration of pemetrexed with oral folic acid and vitamin B12 (FA/B12) in newly diagnosed patients with resectable rectal cancer and (b) intracellular and systemic vitamin metabolism. Patients were treated with three cycles of pemetrexed (500 mg/m, every 3 weeks) and FA/B12 before surgery. The reduced folates tetrahydrofolate, 5-methyltetrahydrofolate, and 5,10-methylenetetrahydrofolate were evaluated from biopsies in tumor tissue and in adjacent mucosa. Serum levels of homocysteine, cystathionine, and methylmalonic acid were also measured. All 37 patients received three cycles of pemetrexed; 89.2% completed their planned dosage within a 9-week feasibility time frame. Neither dose reductions nor study drug-related serious adverse events were reported. Reduced folate levels were significantly higher in tumor tissue compared with adjacent mucosa at baseline. After FA/B12 administration, tissue levels of reduced folates increased significantly and remained high during treatment in both tumor and mucosa until surgery. Serum levels of cystathionine increased significantly compared with baseline after FA/B12 administration, but then decreased, fluctuating cyclically during pemetrexed therapy. Homocysteine and methylmalonic acid levels decreased significantly after FA/B12 administration, and remained below baseline levels during the study. These results indicate that administration of three neoadjuvant cycles of single-agent pemetrexed, every 3 weeks, with FA/B12 in patients with resectable rectal cancer is feasible and tolerable. Tissue and serum vitamin metabolism results demonstrate the influence of pemetrexed and FA/B12 on vitamin metabolism and warrant further study.

GRP78 Protein Expression as Prognostic Values in Neoadjuvant Chemoradiotherapy and Laparoscopic Surgery for Locally Advanced Rectal Cancer.

PURPOSE: We investigated the relationships between biomarkers related to endoplasmic reticulum stress proteins (glucose-regulated protein of molecular mass 78 [GRP78] and Cripto-1 [teratocarcinoma-derived growth factor 1 protein]), pathologic response, and prognosis in locally advanced rectal cancer. MATERIALS AND METHODS: All clinical stage II and III rectal cancer patients received 50.4 Gy over 5.5 weeks, plus 5-fluorouracil (400 mg/m(2)/day) and leucovorin (20 mg/m(2)/day) bolus on days 1 to 5 and 29 to 33, and surgery was performed at 7 to 10 weeks after completion of all therapies. Expression of GRP78 and Cripto-1 proteins was determined by immunohistochemistry and was assessed in 101 patients with rectal cancer treated with neoadjuvant chemoradiotherapy (CRT). RESULTS: High expression of GRP78 and Cripto-1 proteins was observed in 86 patients (85.1%) and 49 patients (48.5%), respectively. Low expression of GRP78 protein was associated with a significantly high rate of down staging (80.0% vs. 52.3%, respectively; p=0.046) and a significantly low rate of recurrence (0% vs. 33.7%, respectively; p=0.008) compared with high expression of GRP78 protein. Mean recurrence-free survival according to GRP78 expression could not be estimated because the low expression group did not develop recurrence events but showed a significant correlation with time to recurrence, based on the log rank method (p=0.007). GRP78 also showed correlation with overall survival, based on the log rank method (p=0.045). CONCLUSION: GRP78 expression is a predictive and prognostic factor for down staging, recurrence, and survival in rectal cancer patients treated with 5-fluorouracil and leucovorin neoadjuvant CRT.

Relationships between SMAD3 expression and preoperative fluoropyrimidine-based chemoradiotherapy response in locally advanced rectal cancer patients.

BACKGROUND: SMAD3, which is accumulated in the nucleus, transcriptionally regulates TGF-ß target genes, playing a significant role in mediating the activities of TGF-ß. In this study, we assessed the roles of TGF-ß1, SMAD3, and phosphorylated SMAD3 expressions in patients with locally advanced rectal cancer following preoperative fluoropyrimidine-based chemoradiotherapy. METHODS: Using immunohistochemistry, we examined TGF-ß1, SMAD3, and phosphorylated SMAD3 expressions in pre-chemoradiotherapy cancer tissues from 86 locally advanced rectal cancer patients. After chemoradiotherapy, 64 of 86 (74.4 %) locally advanced rectal cancer patients were classified as responders (pathological tumor regression grades of 2-4). RESULTS: A multivariate analysis showed that phosphorylated SMAD3 overexpression correlated to poor preoperative chemoradiotherapy responses (P = 0.015; OR 7.218; 95 % CI 1.479-35.229). Furthermore, a poor response (pathological tumor regression grades of 0-1) was an independent predictor of postoperative relapse (P = 0.021; OR 5.452; 95 % CI 1.286-23.113). Additionally, patients with phosphorylated SMAD3 overexpression were found to have a worse disease-free survival (P = 0.023). CONCLUSIONS: Our data suggested that analyzing pre-chemoradiotherapy tumors for phosphorylated SMAD3 overexpression would assist physicians in identifying locally advanced rectal cancer patients who may have a poor response risk to preoperative fluoropyrimidine-based chemoradiotherapy.

Nuclear maspin expression as a predictive marker for fluorouracil treatment response in colon cancer.

BACKGROUND: Maspin is a member of the serpin family of protease inhibitors whose function in colorectal cancer is not fully understood. The objective of this study was to determine whether level of maspin expression could have prognostic or predictive value in colorectal cancer. MATERIAL AND METHODS: Maspin expression was assessed using immunohistochemistry on tissue microarrays obtained from 380 patients with stage II and III colorectal cancer randomized to adjuvant chemotherapy with fluorouracil and levamisole (5-FU/Lev) or to surgery only (control), with scores (0-300) based on presence (0-100) and intensity (0-3) of maspin expression. Associations with disease-free survival (DFS), cancer-specific survival (CSS) and prognostic factors were determined. RESULTS: Maspin expression was predominantly nuclear and present in tumor tissue in 99% of the cases. No associations with clinicopathological factors were identified. In colon cancer patients receiving adjuvant chemotherapy, maspin expression level was significantly associated with CSS [HR 1.43 per 50 points increase in maspin score (p = 0.021)] in multivariate analyses, and a significant interaction between treatment status and maspin expression (p = 0.045) was found. Kaplan-Meier plots from colon cancer patients showed a significant treatment benefit in patients with low maspin expression, but not for individuals with medium/high expression. Level of maspin expression was not significantly related to clinical outcome in rectal cancer or in any of the control groups. CONCLUSIONS: In patients with colon cancer a low nuclear maspin expression was an independent predictor of benefit from adjuvant chemotherapy with 5-FU/Lev. A prognostic value of maspin expression was not found in this material.

Chemoradiation provides a physiological selective pressure that increases the expansion of aberrant TP53 tumor variants in residual rectal cancerous regions.

Neoadjuvant chemoradiotherapy has been introduced in patients with surgically resected rectal cancer and reduced the local recurrence. Heterogeneity exists in rectal cancer, and we hypothesized that there are subclones resistant to chemoradiotherapy within the cancer mass. We performed DNA-targeted sequencing of pre- and post-treatment tumor tissues obtained from 20 rectal cancer patients who received chemoradiotherapy. The variant frequency of the mutant clones was compared between pre- and post-treatment samples of nine non-responder patients. RNA-targeted sequencing of 57 genes related to sensitivity to chemotherapy and radiotherapy was performed for the paired samples. Immunohistochemical analyses of p53 expression were also performed on the paired samples from the nine non-responder patients. DNA-sequencing detected frequent mutations of suppressor genes including TP53, APC and FBXW7 in the post-treatment samples of the nine non-responders. The frequency of TP53 mutations showed significant increases after chemoradiotherapy. RNA-targeted sequencing of 29 tumor tissues demonstrated that decreased expression of three genes and increased expression of four genes were detected in the post-treatment samples. Significantly increased expression of TP53 was observed in the post-treatment samples. Immunohistochemical staining for p53 revealed that increased p53 intensity scores were observed after chemoradiotherapy. These results suggest that the tumors with TP53 mutations tend to accumulate through chemoradiotherapy.

[The combination of neoadjuvant chemoradiotherapy and epidermal growth factor receptor inhibitors in the treatment of rectal adenocarcinoma]. / Neoadjuvantní chemoradioterapie karcinomu rekta v kombinaci s inhibitory receptoru pro rustový epidermální faktor.

Rectal adenocarcinoma, in contrast to colorectal carcinoma, is typical of its high local reccurence rate. Radiotherapy is proved to reduce the incidence of recurrences. Neoadjuvant chemoradiotherapy demonstrated better treatment results than adjuvant chemoradiotherapy. Standard cytotoxic agents involved in combination therapy are 5- flurouracil or capecitabin. Epidermal growth factor receptor (EGFR) is supposed to play an important role in cell- cycle regulation, proliferation, differentiation, and surviving of normal epithelial tissues. EGFR overexpression in patients with rectal adenocarcinoma is associated with radioresistance of malignant tissues, lower rates of patological complete response after neoadjuvant chemoradiation and generally poor survival. There are many clinical studies describing combination of neoadjuvant chemoradiotherapy with EGFR inhibitors, however, this regimen has not gained an acceptance as a standard of treatmentment.

Celecoxib plus chemoradiotherapy for locally advanced rectal cancer: a phase II TCOG study.

BACKGROUND: To report the results of a phase II trial combining celecoxib and preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer. PATIENTS AND METHODS: Patients with clinical stage II or III rectal cancer were treated with radiotherapy of 44 Gy in 22 fractions. Concurrent chemotherapy consisted of oral tegafur-uracil and folinate on days 1-30 and 38-65. Celecoxib (400 mg/day) given from days 1 to 65. Surgery was done on day 70. The expression of cyclooxygenase 2 (COX-2) in tumor tissues was evaluated microscopically as a prognostic factor. RESULTS: From 2008 to 2011, 53 patients completed CRT+ celecoxib therapy and 47 received radical surgery. Grade 3 diarrhea developed in 5 (9%). Grade 4 anemia was seen in 2 (4%). Pathological complete response (pCR) was seen in 6 (13%). T or N downstaging found in 38 (81%). Sphincter preservation was achieved in 77% of low-positioned tumors. Patients with tumors expressing high-level COX-2 after CRT + celecoxib treatment had inferior pelvic control (P = 0.01), disease-free survival (P = 0.04), and overall survival (P = 0.03) than those with low-level expression. CONCLUSIONS: Celecoxib can be safely combined with preoperative CRT for rectal cancer. More intensified adjuvant therapy may be considered for tumors expressing high-level COX-2 after CRT and surgery.

HER2 in high-risk rectal cancer patients treated in EXPERT-C, a randomized phase II trial of neoadjuvant capecitabine and oxaliplatin (CAPOX) and chemoradiotherapy (CRT) with or without cetuximab.

BACKGROUND: HER2 is an established therapeutic target in breast and gastric cancers. The role of HER2 in rectal cancer is unclear, as conflicting data on the prevalence of HER2 expression in this disease have been reported. We evaluated the prevalence of HER2 and its impact on the outcome of high-risk rectal cancer patients treated with neoadjuvant CAPOX and CRT±cetuximab in the EXPERT-C trial. PATIENTS AND METHODS: Eligible patients with available tumour tissue for HER2 analysis were included. HER2 expression was determined by immunohistochemistry (IHC) in pre-treatment biopsies and/or surgical specimens (score 0-3+). Immunostaining was scored according to the consensus panel recommendations on HER2 scoring for gastric cancer. Tumours with equivocal IHC result (2+) were tested for HER2 amplification by D-ISH. Tumours with IHC 3+ or D-ISH ratio ≥2.0 were classified as HER2+. The impact of HER2 on primary and secondary end points of the study was analysed. RESULTS: Of 164 eligible study patients, 104 (63%) biopsy and 114 (69%) surgical specimens were available for analysis. Only 3 of 104 (2.9%) and 3 of 114 (2.6%) were HER2+, respectively. In 77 patients with paired specimens, concordance for HER2 status was found in 74 (96%). Overall, 141 patients were assessable for HER2 and 6 out of 141 (4.3%) had HER2 overexpression and/or amplification. The median follow-up was 58.6 months. HER2 was not associated with a difference in the outcome for any of the study end points, including in the subset of 90 KRAS/BRAF wild-type patients treated±cetuximab. CONCLUSIONS: Based on the low prevalence of expression as recorded in the EXPERT-C trial, HER2 does not appear to represent a useful therapeutic target in high-risk rectal cancer. However, the role of HER2 as a potential predictive biomarker of resistance to anti-EGFR-based treatments and a therapeutic target in anti-EGFR refractory metastatic colorectal cancer (CRC) warrants further investigation. TRIAL REGISTRATION: ISRCTN Register: 99828560.

Upregulation of trefoil factor 3 (TFF3) after rectal cancer chemoradiotherapy is an adverse prognostic factor and a potential therapeutic target.

PURPOSE: Management of locally advanced rectal cancer (RC) consists of neoadjuvant chemoradiotherapy (CRT) with fluoropyrimidines, followed by total mesorectal excision. We sought to evaluate the expression of selected genes, some of which were derived from a previous undirected SAGE (serial analysis of gene expression)-based approach, before and after CRT, to identify mechanisms of resistance. METHODS: This retrospective cohort study included 129 consecutive patients. Quantitative polymerase chain reaction of 53 candidate genes was performed on the biopsy specimen before treatment and on the surgical specimen after CRT. A paired-samples t test was performed to determine genes that were significantly changed after CRT. The result was correlated with patients' disease-free survival. RESULTS: Twenty-two genes were significantly upregulated, and two were significantly downregulated. Several of the upregulated genes have roles in cell cycle control; these include CCNB1IP1, RCC1, EEF2, CDKN1, TFF3, and BCL2. The upregulation of TFF3 was associated with worse disease-free survival on multivariate analyses (hazard ratio, 2.64; P=.027). Patients whose surgical specimens immunohistochemically showed secretion of TFF3 into the lumen of the tumoral microglands had a higher risk of relapse (hazard ratio, 2.51; P=.014). In vitro experiments showed that DLD-1 cells stably transfected with TFF3 were significantly less sensitive to 5-fluorouracil and showed upregulation of genes involved in the transcriptional machinery and in resistance to apoptosis. CONCLUSION: Upregulation of TFF3 after CRT for RC is associated with a higher risk of relapse. The physiological role of TFF3 in restoring the mucosa during CRT could be interfering with treatment efficacy. Our results could reveal not only a novel RC prognostic marker but also a therapeutic target.

Combined modality therapy for rectal cancer: the relative value of posttreatment versus pretreatment CEA as a prognostic marker for disease recurrence.

PURPOSE: To evaluate the prognostic significance of the first postsurgery carcinoembryonic antigen (CEA) level in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation (nCRT) and total mesorectal excision. METHODS: A total of 100 patients underwent nCRT and had baseline and posttreatment CEA levels recorded within 6 months of surgery. The median radiotherapy dose was 50.4 Gy. Eighty-six patients received adjuvant 5-fluorouracil-based chemotherapy. Prognostic factors were analyzed for possible associations with freedom from failure (FFF) by univariate and multivariate analyses. Median follow-up was 30 months. RESULTS: The median CEA (ng/ml) levels at baseline before nCRT, after nCRT, and after total mesorectal excision were 3.6, 1.7, and 1.3, respectively. Pathologic complete response was observed in 22%. FFF at 36 months was 78%. Local failure and distant failure occurred in 4 and 20% of the patients, respectively. On univariate analysis, pathologic complete response, margin status, and both pretreatment and postsurgery CEA levels were associated with recurrence (all P < 0.05). On multivariate analysis, pathologic complete response (P < 0.007), margin status (P < 0.001), and postsurgery CEA level (P = 0.003), but not baseline CEA level (P = 0.2), were found to be associated with recurrence. CONCLUSIONS: After nCRT for rectal cancer, postsurgery CEA level may have more prognostic value than pretreatment level. Patients with a postsurgery CEA level of >2.5 ng/ml have higher rates of recurrence and may warrant closer surveillance.

Value of diffusion-weighted magnetic resonance imaging for prediction and early assessment of response to neoadjuvant radiochemotherapy in rectal cancer: preliminary results.

PURPOSE: To evaluate diffusion-weighted magnetic resonance imaging (DWI) for response prediction before and response assessment during and early after preoperative radiochemotherapy (RCT) for locally advanced rectal cancer (LARC). METHODS AND MATERIALS: Twenty patients receiving RCT for LARC underwent MRI including DWI before RCT, after 10-15 fractions and 1 to 2 weeks before surgery. Tumor volume and apparent diffusion coefficient (ADC; b-values: 0-1000 s/mm(2)) were determined at all time points. Pretreatment tumor ADC and volume, tumor ADC change (∆ADC), and volume change (∆V) between pretreatment and follow-up examinations were compared with histopathologic findings after total mesorectal excision (pathologic complete response [pCR] vs. no pCR, ypT0-2 vs. ypT3-4, T-downstaging or not). The discriminatory capability of pretreatment tumor ADC and volume, ∆ADC, and ∆V for the detection of pCR was compared with receiver operating characteristics analysis. RESULTS: Pretreatment ADC was significantly lower in patients with pCR compared with patients without (in mm(2)/s: 0.94 ± 0.12 × 10(-3) vs. 1.19 ± 0.22 × 10(-3), p = 0.003), yielding a sensitivity of 100% and specificity of 86% for detection of pCR. The volume reduction during and after RCT was significantly higher in patients with pCR compared with patients without (in %: ΔV(during): -62 ± 16 vs. -33 ± 16, respectively, p = 0.015; and ΔV(post): -86 ± 12 vs. -60 ± 21, p = 0.012), yielding a sensitivity of 83% and specificity of 71% for the ΔV(during) and, respectively, 83% and 86% for the ΔV(post). The ∆ADC during (ΔADC(during)) and after RCT (ΔADC(post)) showed a significantly higher value in patients with pCR compared with patients without (in %: ΔADC(during): 72 ± 14 vs. 16 ± 12, p = 0.0006; and ΔADC(post): 88 ± 35 vs. 26 ± 19, p = 0.0011), yielding a sensitivity and specificity of 100% for the ΔADC(during) and, respectively, 100% and 93% for the ΔADC(post). CONCLUSIONS: These initial findings indicate that DWI, using pretreatment ADC, ΔADC(during), and ΔADC(post) may be useful for prediction and early assessment of pathologic response to preoperative RCT of LARC, with higher accuracy than volumetric measurements.

Expression of hypoxia-inducible factor 1α predicts clinical outcome after preoperative hyperthermo-chemoradiotherapy for locally advanced rectal cancer.

Hypoxia-inducible factor 1α (HIF-1α) is an intrinsic marker of tumor hypoxia. It has been considered that hypoxic conditions reduce radiosensitivity, but the role of HIF-1α in patients treated with preoperative therapy for rectal cancer is still unclear. The aim of this study was to evaluate the predictive value of tumor response to preoperative hyperthermo-chemoradiotherapy (HCRT) and the prognostic significance of HIF-1α expression in patients with locally advanced rectal cancer. Between 2003 and 2006, 50 patients with histologically proven rectal adenocarcinoma who underwent HCRT followed by surgery were investigated. HIF-1α expression was immunohistochemically evaluated using pre-treatment biopsies. The total radiation dose was 40-50 Gy and chemotherapy consisted of 5-FU and LV administered by continuous infusion on Day 1-5, Day 15-19, and Day 29-33 during radiotherapy. Hyperthermia treatment was performed for once a week for 2-5 sessions. The surgical operation was performed 8 weeks after HCRT and each resected specimen was graded by histological criteria of the Japanese Classification of Colorectal Carcinoma. The effects of HIF-1α on clinical outcomes were analyzed by univariate and multivariate analysis. Positive HIF-1α expression was recognized in 42.0% of samples (21/50). Resected specimens that showed pathological grades 1, 2, and 3 numbered 17, 24, and 9 cases, respectively. There were no significant differences between the HIF-1α-positive group and HIF-1α-negative group for pathological grading and pCR. Overall survival (OS) rate at 3 years in the HIF-1α-negative group was 85.2%, which was significantly better than the 60.6% in the HIF-1α-positive group. Recurrence-free survival (RFS) rate at 3 years in the HIF-1α-negative group was 82.8%, being significantly better than 47.6% in the HIF-1α-positive group. In addition, elevated HIF-1α expression was significantly correlated with recurrence-free survival and metastasis-free survival rate in multivariate analysis. HIF-1α expression might be predictive of recurrence-free survival and metastasis-free survival rate for rectal cancer patients treated with HCRT.

Securin identifies a subgroup of patients with poor outcome in rectal cancer treated with long-course (chemo)radiotherapy.

BACKGROUND: Securin is an oncogene with functions in cell proliferation, tumour initiation and progression. Its prognostic value in rectal cancer is somewhat unknown. Accordingly, we studied securin expression together with Ki-67 in rectal cancer in relation to preoperative (chemo)radiotherapy (RT) and disease outcome. MATERIAL AND METHODS: Biopsies (n = 65 for securin; n = 57 for Ki-67) and operative specimens (n = 207) from 211 patients treated with short-course RT (n = 87), long-course RT (n = 54) or surgery only (n = 70) were studied with immunohistochemistry (IHC) for securin and Ki-67 expression. In the long-course RT group, 45 patients received chemotherapy (5-fluorouracil or capecitabine) concomitantly with RT. The results of IHC were related to clinicopathological variables, disease outcome and tumour regression grade (TRG) after long-course RT. RESULTS: Both markers showed significant reduction after RT (p < 0.001). No differences in expression was seen in the long-course RT group between the patients with or without concomitant chemotherapy (p = 0.23 for securin; p = 0.31 for Ki-67). Low Ki-67 expression, but not that of securin, in operative specimens was significantly related to excellent TRG (p = 0.02 for Ki-67; p = 0.21 for securin). In univariate survival analysis, excellent TRG predicted longer disease-specific survival (DSS; p = 0.03). In multivariate Cox analysis, high securin expression after long-course (chemo)RT was an independent predictor of shorter DSS (p = 0.036) together with patient age (p = 0.043) and disease recurrence (local or distant; p = 0.009), whereas no similar appearance was seen in other treatment groups. CONCLUSION: Securin expression in rectal cancer is significantly reduced after RT. High securin expression and poor TRG after long-course (chemo)RT are indicators of unfavourable disease outcome.