High Ki67, Bax, and thymidylate synthase expression well correlates with response to chemoradiation therapy in locally advanced rectal cancers: proposal of a logistic model for prediction

Association between Ki67 expression and therapeutic outcome in colon cancer

Ki67 is a commonly used proliferation marker in pathological diagnosis of tumors; however, its prognostic value in colon cancer is controversial. A total of 312 consecutive patients with stage I-III colon cancer who underwent radical surgery with or without adjuvant chemotherapy were included in the present study. Ki67 expression was assessed using immunohistochemistry and was classified according to 25% intervals. The association between Ki67 expression and clinicopathological features was analyzed. Long-term postoperative survival, including disease-free survival (DFS) and overall survival, was calculated, and its association with Ki67 was analyzed. High Ki67 expression (>50%) was associated with improved DFS in patients treated with adjuvant chemotherapy postoperatively, but not in patients who received surgery alone (P=0.138). Ki67 expression was significantly associated with histological differentiation of the tumor (P=0.01), while it was not associated with other clinicopathological factors. Multivariate analysis demonstrated that pathological T and N stage were independent prognostic factors. In conclusion, high Ki67 expression was associated with a good therapeutic outcome in patients receiving adjuvant chemotherapy in colon cancer.

Transcriptomic Analyses of Pretreatment Tumor Biopsy Samples, Response to Neoadjuvant Chemoradiotherapy, and Survival in Patients With Advanced Rectal Cancer

Importance

Neoadjuvant chemoradiotherapy (CRT) is the standard of care for advanced rectal cancer. Yet, estimating response to CRT remains an unmet clinical challenge.

Objective

To investigate and better understand the transcriptomic factors associated with response to neoadjuvant CRT and survival in patients with advanced rectal cancer.

Design, Setting, and Participants

A single-center, retrospective, case series was conducted at a comprehensive cancer center. Pretreatment biopsies from 298 patients with rectal cancer who were later treated with neoadjuvant CRT between April 1, 2004, and September 30, 2020, were analyzed by RNA sequencing. Data analysis was performed from July 1, 2021, to May 31, 2022.

Exposures

Chemoradiotherapy followed by total mesorectal excision or watch-and-wait management.

Main Outcomes and Measures

Transcriptional subtyping was performed by consensus molecular subtype (CMS) classification. Immune cell infiltration was assessed using microenvironment cell populations-counter (MCP-counter) scores and single-sample gene set enrichment analysis (ssGSEA). Patients with surgical specimens of tumor regression grade 3 to 4 or whose care was managed by the watch-and-wait approach for more than 3 years were defined as good responders.

Results

Of the 298 patients in the study, 205 patients (68.8%) were men, and the median age was 61 (IQR, 52-67) years. Patients classified as CMS1 (6.4%) had a significantly higher rate of good response, albeit survival was comparable among the 4 subtypes. Good responders exhibited an enrichment in various immune-related pathways, as determined by ssGSEA. Microenvironment cell populations-counter scores for cytotoxic lymphocytes were significantly higher for good responders than nonresponders (median, 0.76 [IQR, 0.53-1.01] vs 0.58 [IQR, 0.43-0.83]; P < .001). Cytotoxic lymphocyte MCP-counter score was independently associated with response to CRT, as determined in the multivariable analysis (odds ratio, 3.81; 95% CI, 1.82-7.97; P < .001). Multivariable Cox proportional hazards regression analysis, including postoperative pathologic factors, revealed the cytotoxic lymphocyte MCP-counter score to be independently associated with recurrence-free survival (hazard ratio [HR], 0.38; 95% CI, 0.16-0.92; P = .03) and overall survival (HR, 0.16; 95% CI, 0.03-0.83; P = .03).

Conclusions and Relevance

In this case series of patients with rectal cancer treated with neoadjuvant CRT, the cytotoxic lymphocyte score in pretreatment biopsy samples, as computed by RNA sequencing, was associated with response to CRT and survival. This finding suggests that the cytotoxic lymphocyte score might serve as a biomarker in personalized multimodal rectal cancer treatment.

Circulating Biomarkers in Predicting Pathological Response to Neoadjuvant Therapy for Colorectal Cancer

Circulating biomarkers show promise in the management of many cancers. They have become the novel non-invasive approach to complement the current strategies in colorectal cancer (CRC) management. Their ability in guiding diagnosis, evaluating response to treatment, screening and prognosis is phenomenal, especially when it comes to their minimally invasive nature. These “liquid biopsies,” which show potential for replacing invasive surgical biopsies, provide useful information on the primary and metastatic disease by providing an insight into cancer biology. Analysis of blood and body fluids for circulating tumour DNA (ctDNA), carcinoembryonic antigen (CEA), circulating tumour cells (CTC), or circulating micro RNA (miRNA) shows potential for improving CRC management. Recognizing a predictive model to assess response to neoadjuvant chemotherapy would help in better patient selection. This review was conducted with the aim of outlining the use of circulatory biomarkers in current practice and their effectiveness in the management of patients having CRC with a focus on response to neoadjuvant therapy.

Predicting pathological response to chemoradiotherapy for rectal cancer: a systematic review

Introduction: Pathological complete response (pCR) rates of approximately 20% following neoadjuvant long-course chemoradiotherapy for rectal cancer have given rise to non-operative or watch-and-wait (W&W) management. To improve outcomes there has been significant research into predictors of response. The goal is to optimize selection for W&W, avoid chemoradiotherapy in those who won't benefit and improve treatment to maximize the clinical complete response (cCR) rate and the number of patients who can be considered for W&W.Areas covered: A systematic review of articles published 2008-2018 and indexed in PubMed, Embase or Medline was performed to identify predictors of pathological response (including pCR and recognized tumor regression grades) to fluoropyrimidine-based chemoradiotherapy in patients who underwent total mesorectal excision for rectal cancer. Evidence for clinical, biomarker and radiological predictors is discussed as well as potential future directions.Expert opinion: Our current ability to predict the response to chemoradiotherapy for rectal cancer is very limited. cCR of 40% has been achieved with total neoadjuvant therapy. If neoadjuvant treatment for rectal cancer continues to improve it is possible that the treatment for rectal cancer may eventually parallel that of anal squamous cell carcinoma, with surgery reserved for the minority of patients who don't respond to chemoradiotherapy.

The Role of Neutrophil-to-lymphocyte Ratio on the Effect of CRT for Patients With Rectal Cancer

BACKGROUND/AIM

Neutrophil-to-lymphocyte ratio (NLR) is an indicator of systemic inflammation and could be a predictive factor in malignant tumors. The aim of this study was to investigate the impact of NLR in patients with lower rectal cancer who received preoperative chemo-radiotherapy (CRT).

PATIENTS AND METHODS

Forty-eight patients with lower rectal cancer who underwent preoperative CRT and curative resection were enrolled. Blood samples were obtained before and after CRT. The relationship of NLR with clinical outcome was investigated.

RESULTS

Post-CRT NLR was higher compared to pre-CRT NLR. The patients with higher post-CRT NLR tended to have worse pathological response to CRT compared to those with low post-CRT NLR. The patients with high post-CRT NLR showed poorer 5-year overall survival and 3-year disease free survival while there was no correlation according to pre-CRT NLR. The univariate analysis showed that post-CRT stage and post-CRT NLR were associated with a poorer 5-year overall survival.

CONCLUSION

NLR after preoperative CRT could be a potential prognostic indicator for patients with lower rectal cancer.

T-cell complexity and density are associated with sensitivity to neoadjuvant chemoradiotherapy in patients with rectal cancer

Emerging evidence suggests that an increased density of pre-treatment CD8⁺ tumor-infiltrating lymphocytes (TILs) is associated with good response to chemoradiotherapy (CRT) in patients with locally advanced rectal cancer. However, the significance of T-cell complexity in the clinical setting remains unknown. High-throughput T-cell receptor (TCR) β sequencing was applied to quantify the TCR repertoire of pre-treatment biopsies from 67 patients with advanced rectal cancer receiving preoperative CRT. Diversity index was used to represent the complexity of the TCR repertoire in a tumor. Pre-treatment CD8⁺ TIL densities were assessed by immunohistochemistry. Changes in TCR repertoire before and after CRT were also analysed in 23 patients. Diversity indices were significantly higher for good responders than for non-responders (P = 0.031). The multivariate analysis revealed that both CD8⁺ TIL density and TCR diversity index were independently associated with good response to CRT (P < 0.001 and P = 0.049, respectively). Patients who were high for both CD8⁺ TIL density and TCR diversity (double-high) had markedly better responses to CRT than double-low patients (84.2% vs 16.7%, P < 0.0001). Larger changes in TCR repertoires before and after CRT were correlated with better recurrence-free survival (P = 0.027). The complexity and dynamic change in the TCR repertoire might serve as a useful indicator of response to CRT in combination with CD8⁺ TIL density in patients with rectal cancer.

Predictive immunohistochemical features for tumour response to chemoradiotherapy in rectal cancer

Background

Reduced expression of cluster of differentiation (CD) 133 and cyclo‐oxygenase (COX) 2, and increased density of CD8+ tumour‐infiltrating lymphocytes, are associated with a favourable tumour response to preoperative chemoradiotherapy (CRT). This study aimed to evaluate these markers in relation to tumour response after preoperative CRT in two rectal cancer cohorts.

Methods

Patients with low rectal cancer who underwent radical resection and preoperative short‐term CRT in 2001–2007 (retrospective cohort) and long‐term CRT in 2011–2017 (prospective cohort) were analysed. Pretreatment biopsies were stained immunohistochemically using antibodies to determine CD133 and COX‐2 expression, and increased CD8+ density. Outcome measures were tumour regression grade (TRG), tumour downstaging and survival.

Results

For 95 patients in the retrospective cohort, the incidence of TRG 3–4 was 67 per cent when two or three immunohistochemistry (IHC) features were present, but only 20 per cent when there were fewer features (P < 0·001). The incidence of tumour downstaging was higher in patients with at least two IHC features (43 versus 22 per cent with fewer features; P = 0·029). The 49 patients in the prospective cohort had similar rates to those in the retrospective cohort (TRG 3–4: 76 per cent for two or more IHC features versus 25 per cent with fewer features, P < 0·001; tumour downstaging: 57 versus 25 per cent respectively, P = 0·022). Local recurrence‐free survival rates in patients with more or fewer IHC features were similar in the retrospective and prospective cohort (P = 0·058 and P = 0·387 respectively).

Conclusion

Assessment of CD133, COX‐2 and CD8 could be useful in predicting a good response to preoperative CRT in patients with lower rectal cancer undergoing neoadjuvant therapy. Further studies are needed to validate the results in larger cohorts and investigate a survival benefit.

Value of Apparent Diffusion Coefficient for Assessing Preoperative T Staging of Low Rectal Cancer and Whether This Is Correlated With Ki-67 Expression

PURPOSE

To explore the value of the apparent diffusion coefficient (ADC) in assessing preoperative T staging of low rectal cancer and the correlation between ADC value and Ki-67 expression.

METHODS

Data on 77 patients with a proven pathology of low rectal cancer were retrospectively analyzed. All patients underwent a magnetic resonance imaging scan 1 week prior to operation, and the mean ADC value was measured. All tumors were fully removed, and pathologic staging was determined. The Ki-67 expression was determined using immunohistochemical methods in all patients. The correlation between Ki-67 expression and ADC features was studied.

RESULTS

A total of 77 patients with low rectal cancer were included in the study. The pathology type was adenocarcinoma. The numbers of patients with pathological stages T1, T2, T3, and T4 were 9, 23, 32, and 13, respectively. The ADC value of all tumors ranged from 0.60 to 1.20 mm²/s. The average Ki-67 proliferation index was 55.3% ± 20.2%. A significant difference was observed between the preoperative ADC value and pathological T staging of low rectal cancer (P < .01). The more advanced the T stage, the lower the detected ADC values were. A negative correlation was noted between the preoperative ADC value and Ki-67 proliferation index of rectal cancer (r = -0.71, P < .01). When the Ki-67 proliferation index increased, lower ADC values were detected.

CONCLUSION

The ADC values can provide useful information on preoperative tumor staging and may facilitate evaluation of the biological behavior of low rectal cancer. The ADC values should be considered a sensitive image biomarker of rectal cancer.

Nomogram for prediction of pathologic complete remission using biomarker expression and endoscopic finding after preoperative chemoradiotherapy in rectal cancer

Objective

The aim of this study is to develop a nomogram for prediction of pathologic complete remission (pCR) after preoperative chemoradiotherapy (CRT) for rectal cancer.

Methods

mRNA expression levels of seven molecular markers [p53, p21, Ki-67, vascular endothelial growth factor (VEGF), CD133, CD24, CD44] were measured by reverse transcriptase polymerase chain reaction (RT-PCR) in 120 rectal cancers. Endoscopic findings of clinical complete remission (cCR) and biologic variables were used to construct nomogram in the training group (n=80), which was validated in the validation group (n=40).

Results

mRNA expression levels of four markers (p53, p21, Ki67, CD133) correlated with pCR (24/80, 30.0%) in the training group. Low expression of p53 and/or high expression of p21, Ki67 and CD133 showed greater pCR rate. pCR was shown in 18 (69.2%) of 26 cases showing endoscopic cCR in the training group. Higher pCR rate was demonstrated in lower tumor location than middle tumor (19/49, 38.8% vs. 5/31, 16.1%). A nomogram for prediction of pCR was developed from the multivariate prediction model using these six variables, which showed good discrimination ability in the training group [area under the curve (AUC)=0.945] and validation group (AUC=0.922). The calibration plot showed good agreement between actual and predicted pCR in both patient groups.

Conclusions

Nomogram for assessment of pCR can be useful for making treatment decisions after CRT according to predicted responses.

Histogram parameters derived from T2 weighted images are associated with histopathological findings in rectal cancer - a preliminary study

Histogram analysis can better reflect tumor heterogeneity than conventional imaging analysis. The present study analyzed possible correlations between histogram parameters derived from T2 weighted images and histopathological features in rectal cancer. Seventeen patients with histopathological proven rectal adenocarcinoma were retrospectively acquired with prebioptic 3 T MRI and available histopathological specimens. Histogram analysis was performed using an in-house matlab tool conducting a whole lesion measurement. Histopathology was investigated using Ki67 specimens with calculation of Ki67-index as well as cellularity and nucleic areas and CD31 specimens, with estimation of microvessel density. Several histogram parameters correlated with average nucleic area. Skewness showed a moderate correlation with microvessel density (P = 0.54, P = 0.02). None of the parameters correlated with Ki67-index. Skewness derived from T2 weighted images might be used as a surrogate parameter for average nucleic area and microvessel density. However, none of the parameters were associated with proliferation index.

Correlation between the Ki-67 proliferation index and response to radiation therapy in small cell lung cancer

Background

In the breast cancer, the decision whether to administer adjuvant therapy is increasingly influenced by the Ki-67 proliferation index. In the present retrospective study, we investigated if this index could predict the therapeutic response to radiation therapy in small cell lung cancer (SCLC).

Methods

Data from 19 SCLC patients who received thoracic radiation therapy were included. Clinical staging was assessed using the TNM classification system (UICC, 2009; cstage IIA/IIB/IIIA/IIIB = 3/1/7/8). Ki-67 was detected using immunostained tumour sections and the Ki-67 proliferation index was determined using e-Count software. Radiation therapy was administered at total doses of 45–60 Gy. A total of 16 of the 19 patients received chemotherapy.

Results

Patients were divided into two groups, one with a Ki-67 proliferation index ≥79.77% (group 1, 8 cases) and the other with a Ki-67 proliferation index <79.77% (group 2, 11 cases). Following radiation therapy, a complete response (CR) was observed in six cases from group 1 (75.0%) and three cases from group 2 (27.3%). The Ki-67 proliferation index was significantly correlated with the CR rate (P = 0.05), which was significantly higher in group 1 than in group 2 (P = 0.04). The median survival time was 516 days for all patients, and the survival rates did not differ significantly between groups 1 and 2.

Conclusions

Our study is the first to evaluate the correlation between the Ki-67 proliferation index and SCLC tumour response to radiation therapy. Our findings suggest that a high Ki-67 proliferation index might represent a predictive factor for increased tumour radiosensitivity.

Biomarker-Based Scoring System for Prediction of Tumor Response After Preoperative Chemoradiotherapy in Rectal Cancer by Reverse Transcriptase Polymerase Chain Reaction Analysis

BACKGROUND

Numerous molecular markers have been investigated to predict tumor response after preoperative chemoradiotherapy for rectal cancer.

OBJECTIVE

This study aimed to evaluate the predictive value of biomarkers for the prediction of tumor response after preoperative chemoradiotherapy.

DESIGN & SETTING

Tumor specimens have been collected prospectively from 80 patients with rectal cancer who underwent curative resection at 8 weeks after completing preoperative chemoradiotherapy.

MAIN OUTCOME MEASURES

With the use of reverse transcriptase polymerase chain reaction analysis, mRNA expression levels of 7 candidate biomarkers (p53, p21, Ki-67, VEGF, CD133, CD24, and CD44) were evaluated from fresh tumor samples collected before preoperative chemoradiotherapy. The correlation between biomarker expression levels and the pathologic response was assessed based on histopathological staging (pTNM) and tumor regression grade.

RESULTS

The mRNA expression levels of 4 biomarkers (p53, p21, Ki67, and CD133) significantly correlated with tumor regression grade response and pathologic complete response. Patients showing low expression of p53 and/or high expression of p21, Ki67, and CD133 exhibited a significantly greater tumor regression grade response and pathologic complete response rate. A scoring system devised so that 1 point was given for each biomarker whose expression level correlated with pathologic complete response (score range: 0-4) showed that 9 of 62 patients with scores of 0 to 2 achieved pathologic complete response, whereas 15 of 18 patients with scores of 3 to 4 achieved pathologic complete response (14.5% vs 83.3%, p < 0.001). For prediction of pathologic complete response, the scoring system showed 62.5% sensitivity, 94.6% specificity, an 83.3% positive predictive value, and an 85.5% negative predictive value.

LIMITATIONS

Small patient numbers have limitations related to the reproducibility and ability to provide quantitative information. In addition, this study lacks test and validation sets.

CONCLUSIONS

The pretreatment mRNA expression levels of 4 biomarkers correlated with pathologic tumor response after intraoperative chemoradiotherapy in rectal cancer. Furthermore, the scoring system combining values of biomarker expression might have predictive power with high positive and negative predictive values.

Association between Ki67 Index and Clinicopathological Features in Colorectal Cancer

BACKGROUND

Conflicting results have been reported about the association between the Ki67 labeling index (Ki67-Li) and clinical outcome in patients with colorectal cancer (CRC).

PATIENTS AND METHODS

Ki67 expression was assessed by immunohistochemistry (IHC) in 2,233 consecutive CRC cases.

RESULTS

We determined 992 cases to have a low and 1,241 cases to have a high Ki67-Li (representing an approximately 44-56% breakdown in distribution between low versus high patients designated by phenotype). Stage III patients with a high Ki67-Li had higher 3-year disease-free survival (DFS) and overall survival (OS) than those with a low Ki67-Li (DFS 70 vs. 61%; p = 0.02 and OS 75 vs. 64%; p = 0.008). We also found significantly improved 3-year progression-free survival (PFS) for stage IV patients in the high versus the low Ki67-Li group (PFS 14 vs. 10%; p = 0.02). Yet, we found no statistical differences in prognosis for stage I and II patients and in OS for stage IV patients between high versus low Ki67-Li (p > 0.05).

CONCLUSION

Our results suggest that high Ki67-Li can be an independent prognostic biomarker to aid the assessment of patient outcomes in both stage III and IV CRC.

Biological and Prognostic Significance of the Morphological Types and Vascular Patterns in Colorectal Liver Metastases (CRLM): Looking Beyond the Tumor Margin

Patients with encapsulated colorectal liver metastases (CRLM) have a better prognosis than those without a capsule. The reason for the encapsulation is unknown. Hypoxia inducible factor-1α (HIF-1α) increases tumor angiogenesis and tumor tissue expression is associated with reduced survival. Our aim was to determine whether the good prognosis of encapsulated CRLM is associated with reduced HIF-1α expression by the cancer.The study selected only patients who had not undergone neoadjuvant chemotherapy prior to a potentially curative hepatectomy for CRLM. From 30 selected patients, serial sections were cut from a single randomly selected metastasis. Morphology was assessed following H&E staining. Tumor hypoxia, vascular endothelial growth factor (VEGF), proliferation, and microvascular density (MVD) were assessed by immunostaining for HIF-1α and carbonic anhydrase-9 (CA-9), VEGF, Ki67, and cluster of differentiation-31, respectively. MVD was calculated in the vascular hot spots. Pathology was reported without clinical outcome information. Actual long-term survival was recorded.Thirteen (43%) of the cancers were encapsulated CRLM containing glands which were large, complex, and cribriform. Thirteen (43%) were infiltrative CRLM and their glands were small, closely packed, and rounded with vessels in the interglandular fibrous tissue with no capsule; 3 (10%) had a mixed picture. Encapsulated CRLM had a higher expression of HIF-1α (58% vs 8%, P = 0.03), CA-9 (42% vs 0%, P = 0.04), and VEGF (92% vs 25%, P = 0.02). MVD was lower in the encapsulated CRLM group (37 mm vs 143 mm, P < 0.001). The median follow-up was 115 months. The encapsulated CRLM group had a better overall and 5-year survival (relative hazard: 0.58, P = 0.057 and hazard ratio: 0.52, P = 0.044).There are 2 main morphological appearances of CRLM which have very different long-term survival following liver resection surgery. The morphology is associated with differences in expression of HIF-1α, CA-9, VEGF, and angiogenesis.

The preoperative SUVmax for (18)F-FDG uptake predicts survival in patients with colorectal cancer

Background

The study was to investigate whether ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake, analyzed by positron emission tomography (PET), can be used preoperatively to predict survival in Chinese patients with colorectal carcinoma.

Methods

A prospectively maintained colorectal cancer database was retrospectively reviewed between June 2009 and December 2011. All included patients had been newly diagnosed with colorectal cancer (of various stages) and evaluated by ¹⁸F-FDG-PET/computed tomography (CT) within the 2 weeks preceding surgery. Univariate and multivariate analyses were used to determine whether the maximal standardized uptake value (SUVmax) and various clinicopathological and immunohistochemical factors were correlated with survival. Receiver operating characteristics (ROC) curve and Kaplan-Meier survival curve analyses were used to explore whether SUVmax could predict survival in these patients.

Results

A total of 107 patients were enrolled in the study (mean age, 59.26 ± 12.66 years; 66.35 % males), with 77 surviving to the end of follow-up (average 60 months). Univariate analysis indicated that tumor size, TNM stage, nodal metastasis, the ratio of metastasized nodes to retrieved nodes, cyclin D1 immunostaining and SUVmax correlated with survival (P < 0.05). Multivariate analysis showed that only TNM stage and SUVmax were associated with survival (P < 0.05). ROC curve analysis determined the optimal SUVmax cutoff for predicting survival to be 11.85 (sensitivity, 73.3 %; specificity, 75.3 %). Survival was significantly longer in patients with preoperative SUVmax ≤11.85 (P < 0.001, log-rank test).

Conclusions

SUVmax, measured by ¹⁸F-FDG-PET/CT, provides a useful preoperative prognostic factor for patients with colorectal cancer.

Predictive and prognostic biomarkers for neoadjuvant chemoradiotherapy in locally advanced rectal cancer

Locally advanced rectal cancer is regularly treated with trimodality therapy consisting of neoadjuvant chemoradiation, surgery and adjuvant chemotherapy. There is a need for biomarkers to assess treatment response, and aid in stratification of patient risk to adapt and personalise components of the therapy. Currently, pathological stage and tumour regression grade are used to assess response. Experimental markers include proteins involved in cell proliferation, apoptosis, angiogenesis, the epithelial to mesenchymal transition and microsatellite instability. As yet, no single marker is sufficiently robust to have clinical utility. Microarrays that screen a tumour for multiple promising candidate markers, gene expression and microRNA profiling will likely have higher yield and it is expected that a combination or panel of markers would prove most useful. Moving forward, utilising serial samples of circulating tumour cells or circulating nucleic acids can potentially allow us to demonstrate tumour heterogeneity, document mutational changes and subsequently measure treatment response.

Association of beclin 1 expression with response to neoadjuvant chemoradiation therapy in patients with locally advanced rectal carcinoma

Beclin 1 is an essential regulator of autophagy that is induced in response to cellular stress and serves to maintain cell survival in established tumors. We recently demonstrated that Beclin 1 suppression can sensitize colorectal cancer cells to radiation-induced DNA damage and apoptosis. Therefore, we hypothesized that the level of Beclin 1 expression may be associated with radiation sensitivity in vivo. We determined the association of Beclin 1 expression in pretreatment rectal cancer tissues with response to neoadjuvant chemoradiation in surgical resection specimens. Stages II and III (n = 96) rectal adenocarcinoma patients were treated with neoadjuvant chemoradiation followed by surgical resection with curative intent. Beclin 1 was analyzed by immunohistochemistry and the expression level was dichotomized at the median value with categorization into low and high groups. We identified 56 (58.3%) and 40 (41.7%) patients whose tumors had high- versus low-level Beclin 1 expression, respectively. Rectal cancers with high versus low Beclin 1 expression were significantly less likely to be downstaged after chemoradiation treatment (45% [25/55] vs. 58% [22/38]; p = 0.02). In a multivariable analysis adjusted for age, sex, histological grade and baseline tumor node metastasis (TNM) stage, the impact of Beclin 1 expression on tumor downstaging remained statistically significant (p = 0.03). The association of the level of Beclin 1 expression with the rate of tumor downstaging after chemoradiation is consistent with in vitro data, and suggests that Beclin 1 may be a predictive biomarker for the efficacy of chemoradiation in patients with rectal cancer.

Prediction of the preoperative chemoradiotherapy response for rectal cancer by peripheral blood lymphocyte subsets

BACKGROUND

Although neoadjuvant chemoradiotherapy (CRT) has become a standard procedure to downstage locally advanced rectal cancer prior to surgery, markers to predict the response to CRT have not been fully identified. The aim of this study was to identify predictive factors of response to CRT, especially focusing on peripheral blood leukocyte subsets.

METHODS

A total of 45 consecutive patients diagnosed with primary rectal cancer were prospectively enrolled and received CRT followed by curative resection. The numbers of each lymphocyte subset in peripheral blood pre- and post-CRT were analyzed using flow cytometry. According to the pathological response to CRT, patients were classified into high (Hi-R) and low (Lo-R) response groups.

RESULTS

Hi-R cases had significantly higher numbers of pre-CRT lymphocytes (p = 0.018), T lymphocytes (p = 0.009) and helper T lymphocytes (Th lymphocytes, p = 0.015) compared to the Lo-R cases. With the receiver-operating characteristic curve for numbers of pre-CRT T lymphocytes, the area under the curve (AUC) was 0.733, and the optimal cutoff value was 1196/μl, with 76.5% sensitivity, 67.8% specificity, 59.1% positive and 82.6% negative predictive values. The numbers of pre-CRT Th lymphocytes and cytotoxic lymphocytes were both independent predictors of the high CRT response in the multivariate analysis.

CONCLUSIONS

In addition to the direct cytotoxicity of CRT, recent studies have demonstrated the induction of an immunological host response, which also contributed to the tumor regression induced by CRT. Our result suggested the potential role of circulating T lymphocytes in predicting the response to CRT in colorectal cancer patients.

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/m²/day) and leucovorin (20 mg/m²/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.

BCL2 protein signalling determines acute responses to neoadjuvant chemoradiotherapy in rectal cancer

In locally advanced rectal cancer, neoadjuvant chemoradiotherapy is performed prior to surgery to downstage the tumour. Thirty to 40 % of patients do not respond. Defects in apoptotic machinery lead to therapy resistance; however, to date, no study quantitatively assessed whether B cell lymphoma 2 (BCL2)-dependent regulation of mitochondrial apoptosis, effector caspase activation downstream of mitochondria or a combination of both predicts patient responses. In a cohort of 20 rectal cancer patients, we performed protein profiling of tumour tissue and employed validated ordinary differential equation-based systems models of apoptosis signalling to calculate the ability of cancer cells to undergo apoptosis. Model outputs were compared to clinical responses. Systems modelling of BCL2-signalling predicted patients in the poor response group (p = 0.0049). Systems modelling also demonstrated that rectal cancers depended on BCL2 rather than B cell lymphoma-extra large (BCL(X)L) or myeloid cell leukemia 1 (MCL1) for survival, suggesting that poor responders may benefit from therapy with selective BCL2 antagonists. Dynamic modelling of effector caspase activation could not stratify patients with poor response and did not further improve predictive power. We deliver a powerful patient stratification tool identifying patients who will likely not benefit from neoadjuvant chemoradiotherapy and should be prioritised for surgical resection or treatment with BCL2 antagonists.

KEY MESSAGES

Modelling BCL2-family proteins identifies patients unresponsive to therapy. Caspase activation downstream of mitochondria cannot identify these patients. Rectal tumours of poor responders are BCL2- but not BCL-XL-dependent. DR_MOMP allows clinicians to identify patients who would not benefit from therapy. DR_MOMP is also a useful patient stratification tool for BCL2 antagonists.

The role of fibrinogen as a predictor in preoperative chemoradiation for rectal cancer

BACKGROUND

To perform chemoradiotherapy (CRT) effectively, it is clinically beneficial to identify predictors of tumor response after CRT. This study examined the association between plasma fibrinogen level before preoperative CRT and tumor response in advanced rectal cancer.

METHODS

This was a retrospective study of 947 patients who received preoperative CRT followed by curative surgery for primary rectal cancer. We analyzed clinical factors that could be associated with pathologic tumor response in terms of downstaging (ypStage 0-I), primary tumor regression (ypT0-1), and complete response (ypT0N0).

RESULTS

Downstaging was observed in 366 patients (38.6%), primary tumor regression in 187 patients (19.7%) and complete response in 138 patients (14.6%). Multivariate analysis found that pre-CRT carcinoembryonic antigen (CEA) level, fibrinogen level, hemoglobin level, clinical T and N classification, distance from anal verge, and histologic grade were significant predictive factors for downstaging; CEA level, fibrinogen level, and N classification predicted primary tumor regression; CEA level, and fibrinogen level were predictive for complete response.

CONCLUSIONS

This study demonstrated that fibrinogen level was a significant predictor of pathologic tumor response after preoperative CRT.

Gender-related differences in pathological and clinical tumor response based on immunohistochemical proteins expression in rectal cancer patients treated with short course of preoperative radiotherapy

BACKGROUND

Prognostic value of pretreatment expression of proteins in rectal cancer for early pathological tumor response (pTR), clinical tumor response (CTR) to preoperative radiotherapy (RT), and the potential difference between these parameters depending on patient gender is not established.

MATERIAL AND METHODS

One hundred eleven patients were treated with short preoperative course of RT (SCRT) with 5 Gy dose per fraction during 5 days, followed by surgery 3 to 53 days (mean, 21 days) later. Expression of CD34, Ki-67, GLUT-1, Ku70, BCL-2, and P53 proteins was assessed immunohistochemically.

RESULTS

There were 76 men and 35 women. There were 27, 69, and 15 clinical tumor-node-metastasis (cTNM) tumor stages I, II, and III, respectively. Significant differences in Ki-67, GLUT-1, Ku 70, and BCL-2 expressions between male and female tumors were observed for pathological TNM (pTNM) stage and grade. Association between proteins expression and pTNM, pTR, and CTR was analyzed separately for short (≤15 days) and long (>15 days) break between RT and surgery and males and female patients. For SCRT with short break, no protein was significantly related to pTNM; for pTR, higher Ki-67 and lower BCL-2 expression were correlated with pTR. In the male subgroup, BCL-2 overexpression was predictive. For SCRT with long break, none of the proteins was predictive for pTR, but Ki-67, Ku70 (in female subgroup), and BCL-2 expressions were positively correlated with pTNM. BCL-2 overexpression was associated with CTR in the females only.

CONCLUSION

In SCRT, long break in the treatment should be avoided because correlation between Ki-67, KU70, and BCL-2 expressions and pTNM after RT might indicate tumor progression.

P21 and CD166 as predictive markers of poor response and outcome after fluorouracil-based chemoradiotherapy for the patients with rectal cancer

Background

Pre-operative chemoradiotherapy (CRT) is the standard treatment in clinical stage T3/4 or node positive rectal cancer. However, there are no established biomarkers that can predict the pathological response and clinical outcome to CRT.

Methods

Immunohistochemical staining was performed in tissue arrays constructed from core tissue specimens taken before treatment and from operative specimens from 112 patients who received 5-FU based pre-operative CRT and surgery. Expression of Ki67, TS, BAX, EpCAM, p53, p21, EGFR, CD44, CD133, CD166, HIF1α and ALDH1 were assessed and correlated with tumor regression grades and disease free survival.

Results

Of the 112 patients (M/F 74/38, median age: 62), 20 (17.9%) patients achieved pathologic complete remission (pCR). In analyzing the associations between marker expressions and tumor regression grades, high p21 expression at the pretreatment biopsy was significantly associated with non-pCR (p = 0.022) and poor disease free survival (median DFS - low vs high p21: 75.8 vs 58.1 months, p = 0.002). In the multivariate analysis, high p21 expression level at the pre-treatment biopsy was significantly associated with poor DFS (p = 0.001, HR 6.14; 95% CI 2.03, 18.55). High CD166 expression level at the pretreatment biopsy was also associated with poor DFS (p = 0.003; HR 5.61; 95% CI 1.81, 17.35).

Conclusion

These show high p21 and CD166 expression at the pretreatment biopsy were associated with tumor regression and poor prognosis in patients treated with 5-FU based CRT. Larger, prospective and functional studies are warranted to determine the role of p21 and CD166 as predictive biomarker of response to CRT.

Future directions in combined modality therapy for rectal cancer: reevaluating the role of total mesorectal excision after chemoradiotherapy

Most patients who develop rectal cancer present with locoregionally advanced (T3 or node-positive) disease. The standard management of locoregionally advanced rectal cancer is neoadjuvant concurrent chemoradiotherapy (nCRT), followed by radical resection (low-anterior resection or abdominoperineal resection with total mesorectal excision). Approximately 15% of patients can have a pathologic complete response (pCR) at the time of surgery, indicating that some patients can have no detectable residual disease after nCRT. The actual benefit of surgery in this group of patients is unclear. It is possible that omission of surgery in these patients, termed selective nonoperative management, can limit the toxicities associated with standard, multimodal combined modality therapy without compromising disease control. In this review, we discuss the clinical experiences to date using selective nonoperative management and various attempts at escalation of nCRT to improve the number of patients who have a pCR. We also explore several clinical, laboratory, imaging, histopathologic, and genetic biomarkers that have been tested as tools to predict which patients are most likely to have a pCR after nCRT.

Prognostic significance of thymidylate synthase polymorphisms in rectal cancer patients treated with neoadjuvant chemoradiotherapy

AIM

There is a lack of prognostic factors of preoperative chemoradiation for locally advanced rectal cancer. Thymidylate synthase (TS) is the most important target of 5-fluorouracil; three main genetic polymorphisms of TS have been described. We analysed the prognostic value of these in patients with locally advanced rectal cancer treated with fluoropyrimidine-based chemoradiation.

METHOD

Ninety-nine patients treated between November 2001 and March 2009 were included. All were treated by radiotherapy (5040 cGy) and concomitant fluoropyrimidine-based chemotherapy. Three polymorphisms were analysed: (i) a double (2R) or triple (3R) repeat of a 28 base pair (bp) tandem sequence upstream of the ATG codon initiation site in the 5'-terminal regulatory region, (ii) a functional G > C single nucleotide polymorphism present in the second repeat of the 3R alleles and (iii) a 6 bp deletion at nucleotide 1494 in the 3'-untranslated region. DNA was extracted from paraffin-embedded core biopsies taken from the tumour and the genotype was analysed using polymerase chain reaction restriction fragment length polymorphism.

RESULTS

The 6 bp polymorphism was significantly associated with disease-free survival (+ 6 bp/+ 6 bp vs-6 bp/-6 bp, P = 0.032 logistic regression). No differences were found in disease-free survival according to the other polymorphisms studied. No relationship was observed between the different TS genotypes and pathological regression.

CONCLUSION

The study suggests that the TS 6 bp polymorphism may be a predictor of disease-free survival in patients with locally advanced rectal cancer treated with fluoropyrimidine-based chemoradiation.

Thrombocytosis before pre-operative chemoradiotherapy predicts poor response and shorter local recurrence-free survival in rectal cancer

PURPOSE

Although thrombocytosis has been reported in patients with various cancers including the colorectal one, the impact of elevated platelet counts on the response to chemoradiotherapy (CRT) for rectal cancer has not been fully investigated. We investigated the clinical significance of pre- and post-CRT platelet counts in patients with rectal cancer.

METHODS

The medical records of 101 patients with rectal cancer, who had received CRT followed by surgical resection, were retrospectively reviewed. The correlations between the clinicopathological variables and the pre- or post-CRT platelet counts were analyzed. The correlations between tumor regression rate induced by CRT, as evaluated by barium enema and pathological examination, and the pre- or post-CRT platelet counts were also evaluated. Finally, the impact of pre-CRT thrombocytosis on the prognosis of these patients was assessed.

RESULTS

The pre-CRT platelet count correlated with venous invasion and tumor size, and it strongly correlated with the response rate evaluated by barium enema and the grade of pathological tumor regression. Furthermore, patients with pre-CRT thrombocytosis had significantly shorter local recurrence-free survival.

CONCLUSION

Platelet count before CRT should be a promising biomarker for predicting the efficacy of CRT and the risk of local recurrence in rectal cancer patients after CRT.

Elevated CEA levels and low distance of the tumor from the anal verge are predictors of incomplete response to chemoradiation in patients with rectal cancer

BACKGROUND

The objective of this study was to evaluate pretreatment clinical parameters as predictive factors for complete pathological response after long-term chemoradiotherapy (RCT) for rectal cancer. Tumor downstaging after RCT for rectal cancer can be obtained in half of cases, whereas a complete pathological response (CPR) is reported to range between 15 and 30%. It is not possible to foresee before therapies who will respond.

METHODS

Patients with stage II-III rectal cancer that had undergone RCT and rectal resection between January 1995 and October 2010 were considered. Patients were divided in those who achieved a CPR, "CR" group, and those who did not achieve a CPR, "NCR" group. Univariate and multivariate analyses between groups were performed considering the clinical parameters: gender, age, ASA score, preoperative hematic CEA, tumor grading; distance of the tumor from the anal verge, maximum tumor diameter, TNM stage, and neoadjuvant treatment details.

RESULTS

Among 260 patients, 43 (16.5%) achieved a CPR. The two groups resulted homogeneous for age, sex, pretreatment status, and tumor stage. A CEA <5 ng/dl and distance from anal verge >5 cm were correlated with CPR at multivariate analysis. Patients with both these conditions presented a significantly higher CPR rate (30.6%) as well as improved 5-year survival. CPR was also correlated with improved survival.

CONCLUSIONS

Very low tumors with a high serum CEA are very unlikely to reach a CPR. The predictive value of these easily available clinical factors should not be underestimated, and better therapeutic strategies for these tumors are needed.

Survivin expression can predict the effect of chemoradiotherapy for advanced lower rectal cancer

BACKGROUND

Chemoradiotherapy (CRT) has been used to improve local control and survival in patients with advanced rectal carcinoma. However, a significant proportion of patients show poor response to adjuvant CRT. We thus investigated the usefulness of survivin expression as a predictive marker of the CRT response and its characteristics.

METHODS

Forty-three patients with lower rectal cancer who underwent CRT were investigated. All patients received preoperative CRT consisting of TS-1 concurrent with 40 Gy of pelvic irradiation followed by curative resection. The relationship between clinical response, or pathological response, and the expression of survivin of pre-CRT biopsy specimens was evaluated by immunohistochemistry and compared with post-CRT expression.

RESULTS

Positive expression of survivin was observed in 26 of 43 patients (60%) in pre-CRT specimens. Survivin was positively expressed in 77% of stable disease cases, and 43% of partial response (p < 0.05). Regarding the correlation between pathological response and survivin expression, positive expression of survivin was recognized in 75% (18 of 24) of Grade 0 + 1 cases, 50% (7 of 14) of Grade 2 cases, and 20% (1 of 5) of Grade 3 cases. A reverse correlation was recognized between pathological responses and survivin expression (p < 0.05). There were differences in the tumor differentiation between the survivin-positive group and the negative group (p < 0.05). The expression concordance rate was 66% between pre- and post-CRT tissues. In post-CRT tissues, nuclear survivin expression disappeared completely and cytoplasmic expression increased, especially in responder cases.

CONCLUSION

Survivin expression in biopsy could be an important predictive factor of preoperative CRT response.

Bax expression measured by AQUAnalysis is an independent prognostic marker in oral squamous cell carcinoma

Background

Resistance to apoptosis is a hallmark of cancer and proteins regulating apoptosis have been proposed as prognostic markers in several malignancies. However, the prognostic impact of apoptotic markers has not been consistently demonstrated in oral squamous cell carcinoma (OSCC). This inconsistency in reported associations between apoptotic proteins and prognosis can be partly attributed to the intrinsic low resolution and misclassification associated with manual, semi-quantitative methods of biomarker expression measurement. The aim of this study was to examine the association between apoptosis-regulating proteins and clinical outcomes in oral squamous cell carcinoma (OSCC) using the quantitative fluorescence immunohistochemistry (IHC) based AQUAnalysis technique.

Methods

Sixty-nine OSCC patients diagnosed between 1998–2005 in Calgary, Alberta, Canada were included in the study. Clinical data were obtained from the Alberta Cancer Registry and chart review. Tissue microarrays (TMAs) were assembled from triplicate cores of formalin-fixed paraffin embedded pre-treatment tumour tissue. Bax, Bcl-2 and Bcl-XL protein expression was quantified using fluorescent IHC and AQUA technology in normal oral cavity squamous epithelium (OCSE) and OSCC tumour samples. Survival was analyzed using Kaplan-Meier plots and the Cox proportional hazard model.

Results

Bax expression was predominantly nuclear in OCSE and almost exclusively cytoplasmic in OSCC. No similar differences in localization were observed for Bcl-2 or Bcl-XL. Only Bax expression associated with disease-specific survival (DSS), with 5-year survival estimates of 85.7% for high Bax versus 50.3% for low Bax (p = 0.006), in univariate analysis. High Bax expression was also significantly associated with elevated Ki67 expression, indicating that increased proliferation might lead to an improved response to radiotherapy in patients with elevated Bax expression. In multivariate analyses, Bax protein expression remained an independent predictor of DSS in OSCC [HR 0.241 (0.078-0.745), p = 0.013].

Conclusions

The AQUA technique used in our study eliminates observer bias and provides reliable and reproducible estimates for biomarker expression. AQUA also provides essential measures of quality control that cannot be achieved with manual biomarker scoring techniques. Our results support the use of Bax protein expression as a prognostic marker in conjunction with other clinico-pathological variables when designing personalized treatment strategies for OSCC patients.

Combined analysis of dihydropyrimidine dehydrogenase and human equilibrative nucleoside transporter 1 expression predicts survival of pancreatic carcinoma patients treated with adjuvant gemcitabine plus S-1 chemotherapy after surgical resection

BACKGROUND

Although postoperative adjuvant chemotherapy for pancreatic ductal adenocarcinoma (PDAC) improves survival in some patients, the effectiveness varies by individual, and the results remain unsatisfying. The aim of this study was to investigate whether intratumoral dihydropyrimidine dehydrogenase (DPD) and human equilibrative nucleoside transporter 1 (hENT1) expression can predict the survival of PDAC patients treated with adjuvant gemcitabine plus S-1 (GEM+S-1) chemotherapy.

METHODS

Intratumoral DPD and hENT1 expression were examined by immunohistochemistry in 86 PDAC patients who received adjuvant GEM+S-1 chemotherapy after surgical resection (all R0 or R1). Relationships between clinicopathologic factors, including DPD and hENT1 expression, and disease-free or overall survival were evaluated by univariate and multivariate analyses.

RESULTS

DPD and hENT1 expression had no significant relationship with any other clinicopathologic factors. A multivariate disease-free survival analysis revealed that lymph node metastasis (hazard ratio [HR], 2.90: 95% confidence interval [CI], 1.51-5.90; P = 0.001), DPD expression (HR 2.47; 95% CI 1.37-4.44; P = 0.003), and hENT1 expression (HR 2.55; 95% CI 1.37-4.64; P = 0.004) as independent factors. Multivariate overall survival analysis also identified pT factor (HR 3.47; 95% CI 1.08-15.8; P = 0.03), lymph node metastasis (HR 2.08; 95% CI 1.01-4.57; P = 0.04), DPD expression (HR 1.98; 95% CI 1.06-3.71; P = 0.03), and hENT1 expression (HR 2.18; 95% CI 1.10-4.19; P = 0.02) as independent factors.

CONCLUSIONS

Combined analysis of DPD and hENT1 expression predicts the survival of PDAC patients treated with adjuvant GEM+S-1 chemotherapy.

Density of CD4(+) and CD8(+) T lymphocytes in biopsy samples can be a predictor of pathological response to chemoradiotherapy (CRT) for rectal cancer

Background

Although preoperative radiotherapy (RT) is widely used as the initial treatment for locally advanced rectal cancer (RC) in the neoadjuvant setting, factors determining clinical response have not been adequately defined. Radiosensitivity has recently been shown to be greatly affected by immune function of the host.

Methods

In 48 cases of advanced RC, we retrospectively examined the density of tumor infiltrating CD4(+) and CD8(+) T cells using immunohistochemical staining of biopsy samples before CRT, and examined the correlation with tumor response.

Results

The numbers of both CD4(+) and CD8(+) tumor-infiltrating lymphocytes (TIL) in pre-CRT biopsy samples were strongly correlated with tumor reduction ratio evaluated by barium enema. Moreover, the densities of CD4(+) and CD8(+) TIL were significantly associated with histological grade after CRT. The density of CD8(+) TIL was an independent prognostic factor for achieving complete response after CRT.

Conclusions

In RC patients, T lymphocyte-mediated immune reactions play an important role in tumor response to CRT, and the quantitative measurement of TIL in biopsy samples before CRT can be used as a predictor of the clinical effectiveness of CRT for advanced RC.

Prognostic impact of dihydropyrimidine dehydrogenase expression on pancreatic adenocarcinoma patients treated with S-1-based adjuvant chemotherapy after surgical resection

BACKGROUND AND OBJECTIVES

The aim of this study is to investigate the prognostic value of intratumoral expression of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), and orotate phosphoribosyltransferase (OPRT) in patients treated with S-1-based chemotherapy after surgical resection for pancreatic adenocarcinoma.

METHODS

Intratumoral TS, DPD, and OPRT expression was investigated in 106 patients with resected pancreatic adenocarcinoma by immunohistochemistry. Associations between clinicopathological factors, including intratumoral TS, DPD, and OPRT expression, and survival were evaluated by univariate and multivariate analyses.

RESULTS

Of 106 patients, 72 had received S-1-based adjuvant chemotherapy (S-1(+) group), and 34 had not (S-1(-) group). High TS, DPD, and OPRT expression was observed in 64%, 37%, and 66% of patients, respectively. Among S-1(+) group patients, survival was significantly better for patients with low DPD expression than for patients with high DPD expression (P = 0.022). Intratumoral DPD expression was the only independent prognostic factor for patients treated with S-1-based adjuvant chemotherapy by multivariate analysis (P = 0.037). Intratumoral TS and OPRT expression did not appear to influence survival.

CONCLUSIONS

Intratumoral DPD expression may be a relevant predictive marker of survival benefit associated with S-1-based adjuvant chemotherapy for pancreatic adenocarcinoma.

MicroRNA-519d targets MKi67 and suppresses cell growth in the hepatocellular carcinoma cell line QGY-7703

MicroRNAs (miRNAs) are small non-coding RNAs that regulate the translation of target mRNA transcripts. In this study, we demonstrated that miR-519d was downregulated in human HCC and could suppress growth of the human HCC cell line QGY-7703. Bioinformatics analysis indicated that MKi67 was a putative target of miR-519d. In an EGFP reporter system, we confirmed that MKi67 was a direct target gene of miR-519d. Furthermore, knockdown of MKi67 inhibited QGY-7703 cell growth. These findings indicate that miR-519d targets the MKi67 transcript and suppresses HCC cell growth, suggesting that miR-519d has a tumor suppressive role in human HCC pathogenesis.

Predictive factors of the response of rectal cancer to neoadjuvant radiochemotherapy

Locally advanced rectal cancer is currently treated with pre-operative radiochemotherapy (pRCT), but the response is not uniform. Identification of patients with higher likelihood of responding to pRCT is clinically relevant, as patients with resistant tumors could be spared exposure to radiation or DNA-damaging drugs that are associated with adverse side effects. To highlight predictive biomarkers of response to pRCT, a systematic search of PubMed was conducted with a combination of the following terms: "rectal", "predictive", "radiochemotherapy", "neoadjuvant", "response" and "biomarkers". Genetic polymorphisms in epithelial growth factor receptor (EGFR) and thymidylate synthase (TS) genes, the expression of several markers, such as EGFR, bcl-2/bax and cyclooxygenase (COX)-2, and circulating biomarkers, such as serum carcinoembryonic antigen (CEA) level, are promising as predictor markers, but need to be further evaluated. The majority of the studies did not support the predictive value of p53, while the values of Ki-67, TS and p21 is still controversial. Gene expression profiles of thousands of genes using microarrays, microRNA studies and the search for new circulating molecules, such as human telomerase reverse transcriptase mRNA and cell-free DNA, are providing interesting results that might lead to the identification of new useful biomarkers. Evaluation of biomarkers in larger, prospective trials are required to guide therapeutic strategies.

Thymidylate synthase as a prognostic biomarker for locally advanced rectal cancer after multimodal treatment

Purpose

For years, 5-fluorouracil (5-FU) has been the backbone of radiochemotherapy (RCT) of locally advanced rectal cancer. Its main target, thymidylate synthase (TS), is speculated to be an important biomarker for response prediction and long-term prognosis. In this study, we analyzed TS expression in the rectal cancer tissue of 208 patients to evaluate its predictive/prognostic potential.

Methods

All patients included were diagnosed with locally advanced adenocarcinoma of the rectum (UICC II and III) and were treated within randomized clinical trials of the German Rectal Cancer Study Group. Preoperative RCT (50.4 Gy and concomitant either 5-FU or 5-FU and oxaliplatin) was administered in 167 patients followed by surgical resection with total mesorectal excision (TME). Another 41 patients received postoperative RCT. TS levels and further clinicopathological parameters were assessed in univariate and multivariate analyses. Additionally, a TS gene polymorphism was analyzed with respect to the intratumoral protein levels.

Results

Low TS expression in pretreatment biopsies correlated with impaired patient survival (p = 0.015). Analysis of a 28-bp repeat revealed a correlation between the *3/*3 genotype and high TS expression in pretherapeutic biopsies. In this study, a correlation of TS expression and grade of RCT-induced tumor regression was not found. Histopathological examination confirmed a complete tumor remission in 16 patients (9.6%).

Analyses of the resection specimen indicated an unfavorable prognosis for patients with low intratumoral TS expression in case of detected lymph node metastases (p = 0.04).

Conclusions

TS can serve as a prognostic biomarker indicating an unfavorable prognosis for patients with low TS expression.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-011-1608-4) contains supplementary material, which is available to authorized users.

Circulating lymphocyte is an important determinant of the effectiveness of preoperative radiotherapy in advanced rectal cancer

Background

Although preoperative radiotherapy (RT) is widely used as the initial treatment for locally advanced rectal cancer (RC) in the neoadjuvant setting, factors determining clinical response have not been adequately defined. In order to find other factors possibly related with radiosensitivity, we evaluated the relationships between circulating blood cell counts and RT effects.

Methods

In 179 cases with advanced RC, we retrospectively examined hemoglobin (Hb) levels and counts of white blood cells (WBC), platelets and WBC subsets before and after RT and investigated their associations with the complete response (CR) rate together with other clinicopathological factors.

Results

The ratio of lymphocytes in WBC taken before RT was significantly greater in 15 CR cases as compared with those in non-CR cases. Patients with high lymphocyte percentages (25.7%) showed better outcome than the counterparts. Conversely, the ratio of neutrophiles was reduced in CR cases. The lymphocyte ratio showed an independent association with CR with multivariate analysis, and tended to be maintained at relatively high levels in CR cases.

Conclusions

In RC patients, peripheral blood lymphocytes have a significant impact on the CR rate in response to RT. Lymphocyte-mediated immune reactions are supposed to have positive roles on clinical response in radiotherapy for RC.

Hyperfibrinogenemia after preoperative chemoradiotherapy predicts poor response and poor prognosis in rectal cancer

PURPOSE

Although hyperfibrinogenemia has been reported in patients with colorectal cancer, neither its clinical implications nor the effect of chemoradiotherapy (CRT) on the fibrinogen levels have been fully investigated. We investigated the clinical significance of pre- and post-CRT fibrinogen levels in patients with rectal cancer.

METHODS

The medical records of 82 patients with rectal cancer, who had received CRT followed by surgical resection, were retrospectively reviewed. The correlation between the clinicopathological variables and the pre- and post-CRT plasma fibrinogen levels, and that between the changes of fibrinogen, C-reactive protein (CRP), or carcinoembryonic antigen (CEA) levels after CRT and the pathological tumor regression grading was analyzed. Furthermore, the impact of post-CRT fibrinogen levels on the prognosis of these patients was assessed.

RESULTS

Plasma fibrinogen markedly decreased after CRT. The post-CRT fibrinogen level significantly correlated with lymphatic invasion, venous invasion, tumor size, depth of invasion, and the pathological tumor regression grading. The CRT-induced pathological tumor regression grading well correlated with the decrease of fibrinogen level, but not with that of CRP or CEA. Furthermore, patients with high post-CRT fibrinogen had significantly shorter disease-free survival.

CONCLUSIONS

Reduction of plasma fibrinogen induced by CRT should be a promising biomarker for evaluating the efficacy of CRT in rectal cancer patients.

Role of tumor size in the pre-operative management of rectal cancer patients

Background

Clinical management of rectal cancer patients relies on pre-operative staging. Studies however continue to report moderate degrees of over/understaging as well as inter-observer variability. The aim of this study was to determine the sensitivity, specificity and accuracy of tumor size for predicting T and N stages in pre-operatively untreated rectal cancers.

Methods

We examined a test cohort of 418 well-documented patients with pre-operatively untreated rectal cancer admitted to the University Hospital of Basel between 1987 and 1996. Classification and regression tree (CART) and logistic regression analysis were carried out to determine the ability of tumor size to discriminate between early (pT1-2) and late (pT3-4) T stages and between node-negative (pN0) and node-positive (pN1-2) patients. Results were validated by an external patient cohort (n = 28).

Results

A tumor diameter threshold of 34 mm was identified from the test cohort resulting in a sensitivity and specificity for late T stage of 76.3%, and 67.4%, respectively and an odds ratio (OR) of 6.67 (95%CI:3.4-12.9). At a threshold value of 29 mm, sensitivity and specificity for node-positive disease were 94% and 15.5%, respectively with an OR of 3.02 (95%CI:1.5-6.1). Applying these threshold values to the validation cohort, sensitivity and specificity for T stage were 73.7% and 77.8% and for N stage 50% and 75%, respectively.

Conclusions

Tumor size at a threshold value of 34 mm is a reproducible predictive factor for late T stage in rectal cancers. Tumor size may help to complement clinical staging and further optimize the pre-operative management of patients with rectal cancer.

Circulating lymphocyte number has a positive association with tumor response in neoadjuvant chemoradiotherapy for advanced rectal cancer

Although neoadjuvant chemoradiotherapy (CRT) is the standard treatment for advanced rectal cancer (RC), markers to predict the treatment response have not been fully established. In 73 patients with advanced RC who underwent CRT in a neoadjuvant setting, we retrospectively examined the associations between the clinical effects of CRT and blood cell counts before and after CRT. Clinical or pathological complete response (CR) was observed in 10 (14%) cases. The CR rate correlated significantly with the size and the circumferential extent of the tumor. Hemoglobin level, white blood cell (WBC) count and platelet count before CRT did not show a significant difference between CR and non-CR cases. Interestingly, however, lymphocyte ratio in WBC was significantly higher (p = 0.020), while neutrophil ratio tended to be lower (p = 0.099), in CR cases, which was shown to be an independent association by multivariate analysis. When all the blood data obtained in the entire treatment period were evaluated, circulating lymphocyte count was most markedly decreased in the CRT period and gradually recovered by the time of surgery, while the numbers of neutrophils and monocytes were comparatively stable. Moreover, the lymphocyte percentage in samples obtained from CR patients was maintained at a relatively higher level than that from non-CR patients. Since tumor shrinkage is known to be dependent not only on the characteristics of tumor cells but also on various host conditions, our data raise the possibility that a lymphocyte-mediated immune reaction may have a positive role in achieving complete eradication of tumor cells. Maintenance of circulating lymphocyte number may improve the response to CRT in rectal cancer.

Pharmacogenetic analysis in neoadjuvant chemoradiation for rectal cancer: high incidence of somatic mutations and their relation with response

Aims: The identification of predictive markers of response to chemoradiotherapy treatment remains a promising approach for patient management in order to obtain the best response with minor side effects. Initially, we investigated whether the analysis of several markers previously studied and others not yet evaluated could predict response to 5-fluorouracil- and capecitabine-based neoadjuvant treatment in locally advanced rectal cancer. Methods & materials: We studied germline and tumoral samples of 65 stage II/III rectal patients. A panel of pharmacogenetic markers was genotyped in paired peripheral blood samples and rectal cancer tumors. Results: Our results seem to confirm the previously described association of thymidylate synthase and the prediction of chemoradiotherapy response in rectal cancer. However, it failed to confirm the clinical utility proposed for XRCC1, ERCC1, ERCC2, MTHFR and EGFR polymorphisms in blood/germline samples. Subsequently, with the aim of improving prediction of individual response and assessing the role of studied polymorphisms in response to treatment, we determined if changes in tumor response to these markers could predict clinical outcome. We found a high degree of changes between germline and tumor samples, mainly somatic mutations without microsatellite instability, and a minor frequency of loss-of-heterozygosity events. In tumoral samples, XRCC1 appeared to be significantly associated (p = 0.006) with downstaging of the tumor (odds ratio: 7.93; 95% CI: 1.03–60.83), but the increasing of TYMS low-expression alleles contradict the previous results observed in germline samples. Conclusion: The detection of somatic mutations in rectal cancer tumors led us to re-evaluate the utility of the tests performed in blood samples for these polymorphisms in rectal cancer. Furthermore, studies aimed at assessing the influence of pharmacogenetic markers in treatment response performed in blood samples should take into account the particular pattern of hypermutability present in each tumor type. We hypothesize that different patterns of hypermutability present in each tumor type would be related to the different results in association studies related to response to the treatment.