Biological and Clinical Characteristics of Proximal Colon Cancer: Far from Its Anatomical Subsite.

Colorectal cancer is a heterogeneous disease which can be divided into proximal colon cancer, distal colon cancer and rectal cancer according to the anatomical location of the tumor. Each anatomical location of colorectal cancer exhibits distinct characteristics in terms of incidence, clinical manifestations, molecular phenotypes, treatment, and prognosis. Notably, proximal colon cancer differs significantly from cancers of other anatomical subsites. An increasing number of studies have highlighted the presence of unique tumor biological characteristics in proximal colon cancer. Gaining a deeper understanding of these characteristics will facilitate accurate diagnosis and treatment approaches.

Comparing cranial-caudal-medial and medial-lateral approaches for laparoscopic right hemicolectomy: a propensity score-matched analysis.

BACKGROUND: The cranial-caudal-medial approach (CCMA) has been proposed for laparoscopic right hemicolectomy nowadays. This study aimed to investigate the safety and oncological efficacy of CCMA in the treatment of right-sided colon cancer compared to the medial-lateral approach (MLA). METHODS: Patients diagnosed with right-sided colon cancer were included from February 2015 to June 2018, retrospectively, dividing into the CCMA group and the MLA group. We compared the basic characteristics and the short-term and long-term outcomes in two groups. RESULTS: Two hundred and ninety-six patients were included in this study. The baseline characteristics were similar in two groups. Compared with MLA group, CCMA group exhibited shorter operation time (136.3 ± 25.3 min vs. 151.6 ± 21.5 min, P < 0.001), lower estimated blood loss (44.1 ± 15.2 ml vs. 51.4 ± 26.9 min, P = 0.010), and more harvested lymph nodes (18.5 ± 7.1 vs. 16.5 ± 5.7, P = 0.021). The 5-year overall survival (OS) rate for the CCMA group was 76.5%, and the 5-year disease-free survival (DFS) rate was 72.3%, both of which were not inferior to the MLA group. No significant difference was found between two groups in terms of other clinical parameters. CONCLUSION: The CCMA in laparoscopic right hemicolectomy is safe and feasible, making the anatomical plane clearer. This approach can shorten the operation time, reduce intraoperative blood loss, harvest more lymph nodes, and yield satisfactory oncological outcomes.

Unraveling the role of tumor sidedness in prognosis of stage II colon cancer.

Background: Stage II colon cancer has varying risks for metastasis, and treatment strategies depend on molecular and clinicopathological features. While tumor-sidedness is a well-accepted prognostic factor for stage III/IV colon cancer, its role in stage II is controversial. Understanding its effect in stage II is crucial for improving treatment strategies. Methods: We analyzed clinical and follow-up data of colon cancer from the Surveillance, Epidemiology, and End Results database (2004-2017). Patients were divided into a primary study cohort (2010-2017) and a validation cohort (2004-2009). The baseline characteristics between right-sided colon cancer (RCC) and left-sided colon cancer (LCC) groups were compared. Moreover, the effect of tumor size on cancer-specific survival (CSS) was evaluated using Kaplan-Meier analysis. Results: The study involved 87,355 patients in the study cohort and 65,858 in the validation cohort. Of the study cohort, 52.3% were diagnosed with RCC. The median age was 64 years old, with 48.5% females and 76.8% of white people. In addition, stage II RCC showed better CSS compared with LCC (5-year CSS 88.0% vs 85.5%, P < 0.001), while stage III/IV RCC demonstrated poorer outcomes. Multivariate Cox regression analysis identified that the right-sidedness was a positive prognostic factor in stages I/II but negative in stages III (HR 1.10, P < 0.001) and IV (HR 1.26, P < 0.001). Chemotherapy rates decreased in RCC, particularly in stage II (RCC vs LCC: 16.2% vs 28.5%, P < 0.001). Subgroup analysis, stratified by T3/T4 stages and chemotherapy status, further highlighted better survival outcomes in RCC. Conclusions: RCC is associated with a significantly better prognosis in stage II. The importance of considering tumor-sidedness in clinical decision-making and the design of future clinical trials should be emphasized.

Survival trends for left and right sided colon cancer using population-based SEER database: A forty-five-year analysis from 1975 to 2019.

BACKGROUND: Survival differences between left-sided colon cancer (LSCC) and right-sided colon cancer (RSCC) has been previously reported with mixed results, with various study periods not accounting for other causes of mortality. PURPOSE: We sought to assess the trends in colon cancer cause- specific survival (CSS) and overall survival (OS) based on sidedness. METHOD: Fine-Gray competing risk and Cox models were used to analyze Surveillance, Epidemiology, and End Results (SEER) population-based cohort from 1975 to 2019. Various interval periods were identified based on the timeline of clinical adoption of modern chemotherapy (1975-1989, interval period A; 1990-2004, B; and 2005-2019, C). RESULTS: Of the 227,637 patients, 50.1% were female and 46.2% were RSCC. RSCC was more common for African Americans (51.5%), older patients (age ≥65; 51.4%), females (50.4%), while LSCC was more common among Whites (53.1%; p < 0.001), younger patients (age 18-49, 64.6%; 50-64, 62.3%; p < 0.001), males (58.1%; p < 0.001). The Median CSS for LSCC and RCC were 19.3 and 16.7 years respectively for interval period A (1975-1989). Median CSS for interval periods B and C were not reached (more than half of the cohort was still living at the end of the follow-up period). Adjusted CSS was superior for LSCC versus RSCC for the most recent interval period C (HR 0.89; 0.86-0.92; p < 0.001). LSCC consistently showed superior OS for all study periods. Stage stratification showed worse CSS for localized and regional LSCC in the earlier study periods, but the risk attenuated over time. However, left sided distant disease had superior CSS per stage for all interval periods. OS was better for LSCC irrespective of stage, with gradual improvement over time. CONCLUSION: LSCC was associated with superior survival compared to right sided tumors. With the adoption of modern chemotherapy regimens, prognosis between LSCC and RSCC became more divergent in favor of LSCC. Colon cancer clinical trials should strongly consider tumor sidedness as an enrollment factor.

Prognostic nomogram in patients with right-sided colon cancer after colectomy: a surveillance, epidemiology, and end results-based study.

Objective: This study aimed to develop and validate a nomogram for predicting overall survival (OS) in patients undergoing surgery for right-sided colon cancer (RCC). Methods: We collected 25,203 patients with RCC from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided them into 7:3 training and internal validation set. Utilizing the Cox proportional hazards regression model, we constructed a nomogram based on prognostic risk factors. Furthermore, for external validation, we retrospectively followed up with 228 patients from Jiaxing First Hospital and assessed and calibrated the nomogram using the C-index and calibration curves. Results: After identifying independent prognostic factors through univariate and multivariate analyses, a nomogram was developed. The c-index values of this nomogram differed as follows: 0.851 (95% CI: 0.845-0.857) in the training set, 0.860 (95% CI: 0.850-0.870) in the internal validation set, and 0.834 (95% CI: 0.780-0.888) in the external validation set, indicating the model's strong discriminative ability. Calibration curves for 1-year, 3-year, and 5-year overall survival (OS) probabilities exhibited a high level of consistency between predicted and actual survival rates. Furthermore, Decision Curve Analysis (DCA) demonstrated that the new model consistently outperformed the TNM staging system in terms of net benefit. Conclusion: We developed and validated a survival prediction model for patients with RCC. This novel nomogram outperforms the traditional TNM staging system and can guide clinical practitioners in making optimal clinical decisions.

Prognostic impact of primary tumour location after curative resection in Stage I-III colorectal cancer: a single-centre retrospective study.

OBJECTIVE: The relationship of tumour site with post-recurrence course and outcome after primary surgery in resectable colorectal cancer is unclear. This study investigated the prognostic impact of primary tumour location following radical resection without preoperative treatment in Stage I-III colorectal cancer. METHODS: We analyzed 3770 patients with Stage I-III colorectal cancer who underwent curative resection at our hospital during 2000-15. We defined the right-sided colon as the cecum, ascending colon and transverse colon, and the left-sided colon as the descending colon, sigmoid and rectosigmoid junction. Patients were divided into three groups according to tumour site: right-sided colon, left-sided colon and rectum. Endpoints were overall survival, recurrence-free survival by stage and survival after recurrence, respectively. RESULTS: The 5-year overall survival rates of patients with stage I left-sided colon cancer, right-sided colon cancer and rectal cancer were 98.2, 97.3 and 97.2%, respectively (P = 0.488). The 5-year overall survival rates of patients with Stage II left-sided colon cancer, right-sided colon cancer and rectal cancer were 96.2, 88.7 and 83.0, respectively (P = 0.070). The 5-year overall survival rates of patients with Stage III left-sided colon cancer, right-sided colon cancer and rectal cancer were 88.7, 83.0 and 80.2, respectively (P = 0.001). The 5-year recurrence-free survival rates of patients with Stage I left-sided colon cancer, right-sided colon cancer and rectal cancer were 95.1, 94.5 and 90.6% (P = 0.027). The 5-year recurrence-free survival rates of patients with Stage II left-sided colon cancer, right-sided colon cancer and rectal cancer were 85.2, 90.2 and 76.1%, respectively (P < 0.001). The 5-year recurrence-free survival rates of patients with Stage III left-sided colon cancer, right-sided colon cancer and rectal cancer were 75.3, 75.3 and 59.8%, respectively (P < 0.001). Right-sided colon cancer was significantly associated with better recurrence-free survival compared with left-sided colon cancer (HR 1.29, 95% CI 1.03-1.63; P = 0.025) and rectal cancer (HR 1.89, 95% CI 1.51-2.38; P < 0.001) after adjusting for clinical factors. Amongst patients with recurrence, right-sided colon cancer was significantly associated with poorer survival after recurrence compared with left-sided colon cancer (HR 0.68, 95% CI 0.48-0.97; P = 0.036), and showed a tendency towards poorer survival after recurrence compared with rectal cancer (HR 0.79, 95% CI 0.57-1.10; P = 0.164). CONCLUSIONS: In Stage I-III colorectal cancer without preoperative treatment, our results suggest that the three tumour sites (right-sided colon, left-sided colon or rectum) may have prognostic significance for recurrence-free survival and survival after recurrence, rather than sidedness alone.

HLA class II polymorphisms as prognostic biomarkers for right and left-sided colon cancer.

BACKGROUND: Colon cancer (CC) is one of the most common malignancies worldwide. Characterization of new prognostic biomarkers for right-sided CC (RCC) and left-sided CC (LCC) may contribute to improving early detection. An association of human leukocyte antigens class II (HLA-II) with the predisposition to CC was suggested. AIM OF THE STUDY: We evaluated the association of DRB1 and DQB1 with the risk of LCC and RCC. PATIENTS AND METHODS: Our study comprised 93 CC patients and 100 healthy controls. Genotyping of HLA class II alleles were performed by the Polymerase Chain Reaction Sequence-Specific Primers (PCR-SSP). RESULTS: DRB1*03 was positively associated with CC. In contrast, DRB1*11, DRB1*13, DQB1*03, and DQB1*05 were negatively linked to CC. Haplotype analysis revealed that DRB1*04-DQB1*04 and DRB1*09-DQB1*02 were positive, while DRB1*01-DQB1*05, DRB1*04-DQB1*03, DRB1*07-DQB1*02, DRB1*11-DQB1*03, DRB1*11-DQB1*05, and DRB1*13-DQB1*06 were negatively associated with CC. For sigmoid CC, DRB1*13, DRB1*11, and DQB1*05 were negative, while DRB1*04-DQB1*02, and DRB1*07-DQB1*03 were positively associated. DRB1*03 and DRB1*04-DQB1*04 were positive, while DRB1*11 and DQB1*03 were negatively linked to RCC. According to the LCC, DRB1*07, DRB1*11, DQB1*03, DQB1*05, and DRB1*07-DQB1*02 were negative. In contrast, DRB1*09-DQB1*02 was positively associated with LCC. Stratified analysis revealed that DRB1*11 is associated with higher risk of metastasis in CC and sigmoid CC, and tolerance to treatment in RCC. DQB1*03 was associated with lymph-node invasion in CC. CONCLUSION: DRB1 and DQB1 polymorphisms could be used as future biomarkers for the early detection of subjects at a higher risk of developing RCC and LCC, metastasis in sigmoid CC, and tolerance to treatment in RCC.

Study on the Difference of Gene Expression Between Left and Right Colon Cancer and the Mechanism of Sophorae Flavescentis Radix-Sargentodoxae Caulis-Scutellariae Barbatae Herba Based on TCGA / 广州中医药大学学报

Abstact:Objective To investigate the gene expression differences between left-sided colon cancer and right-sided colon cancer and the mechanism differences between the colorectal cancer core drug pairs of Sophorae Flavescentis Radix-Sargentodoxae Caulis-Scutellariae Barbatae Herba acting on left-sided and right-sided colon cancer.Methods The transcriptome data of 134 patients with left-sided colon cancer and 194 patients with right-sided colon cancer from The Cancer Genome Atlas(TCGA)were downloaded,and the R software was applied to realize the differential gene analysis of the two groups and the enrichment analysis of Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway;the BATMAN-TCM database was used to obtain the active ingredients and targets of the drug pair of Sophorae Flavescentis Radix-Sargentodoxae Caulis-Scutellariae Barbatae Herba,and based on the different genes of the left-and right-sided colon cancers,KEGG enrichment analysis of the drug pair-left/right-sided colon cancers was performed respectively,and the protein-protein-interaction(PPI)network was constructed to compare the differences of the biosignaling pathways enriched by the drug pairs for the treatment of left-and right-sided colon cancers,as well as the differences of the key target points.Results There were 6 051 differentially expressed genes common to left-and right-sided colon cancers relative to normal paracancerous tissues,1958 differentially expressed genes specific to left-sided colon cancer,and 1739 differentially expressed genes specific to right-sided colon cancer;14 KEGG-enriched pathways specific to left-sided colon cancer,and 23 KEGG-enriched pathways specific to right-sided colon cancer.There were 85 active compounds in the drug-pair of Sophorae Flavescentis Radix-Sargentodoxae Caulis-Scutellariae Barbatae Herba,corresponding to a total of 469 targets.The drug-pair-left-sided colon cancer targets were enriched in 10 KEGG signaling pathways,with the key targets being DRD2,CACNA1C,HTR3A,COMT,and TH;and the drug-pair-right-sided colon cancer targets were enriched in 1 KEGG signaling pathway,with the core targets being HTR3A,DRD2 TH,AGT,GRIN2B.Conclusion There are gene expression differences between left-and right-sided colon cancers:left-sided colon cancer is associated with abnormal immune function,abnormal AMPK signaling pathway and other mechanisms,and right-sided colon cancer is associated with neutrophil extracellular trap formation,alcoholism,abnormal Hippo signaling pathway and other mechanisms.In addition to regulating cell cycle and essential amino acid metabolism and other mechanisms,Sophorae Flavescentis Radix-Sargentodoxae Caulis-Scutellariae Barbatae Herba drug pairs have specific effects on regulating the intestinal endocrine function of the left-sided colon cancer,inhibiting inflammatory response of the right-sided colon cancer,and may also have mood-regulating effects on patients with colon cancer.

Best Evidence for Each Surgical Step in Minimally Invasive Right Hemicolectomy: A Systematic Review.

Objective: The aim of this study was to systematically review the literature for each surgical step of the minimally invasive right hemicolectomy (MIRH) for non-locally advanced colon cancer, to define the most optimal procedure with the highest level of evidence. Background: High variability exists in the way MIRH is performed between surgeons and hospitals, which could affect patients' postoperative and oncological outcomes. Methods: A systematic search using PubMed was performed to first identify systematic reviews and meta-analyses, and if there were none then landmark papers and consensus statements were systematically searched for each key step of MIRH. Systematic reviews were assessed using the AMSTAR-2 tool, and selection was based on highest quality followed by year of publication. Results: Low (less than 12 mmHg) intra-abdominal pressure (IAP) gives higher mean quality of recovery compared to standard IAP. Complete mesocolic excision (CME) is associated with lowest recurrence and highest 5-year overall survival rates, without worsening short-term outcomes. Routine D3 versus D2 lymphadenectomy showed higher LN yield, but more vascular injuries, and no difference in overall and disease-free survival. Intracorporeal anastomosis is associated with better intra- and postoperative outcomes. The Pfannenstiel incision gives the lowest chance of incisional hernias compared to all other extraction sites. Conclusion: According to the best available evidence, the most optimal MIRH for colon cancer without clinically involved D3 nodes entails at least low IAP, CME with D2 lymphadenectomy, an intracorporeal anastomosis and specimen extraction through a Pfannenstiel incision.

Short- and Long-Term Survival among Elderly Colorectal Cancer Patients in Finland, 2006-2015: A Nationwide Population-Based Registry Study.

This population-based registry study aimed to report 30-day and one-year postoperative survival, five-year overall survival (OS), and disease-specific survival (DSS) among elderly (≥75 years old) colorectal cancer (CRC) patients. All new colorectal cancer cases from 2006-2015 were included and followed until death or the end of follow-up (end of 2016). Among 27,088 CRC patients, 11,306 patients were ≥75 years old. Among patients ≥ 75 years, 36.8% (n = 4160) had right-sided colon cancer, 21.9% (n = 2478) left-sided colon cancer, and 32.3% (n = 3650) rectal cancer. In this study population, 932 patients were aged ≥ 90. The 30-day postoperative OS for patients aged 75-79 was 96.1% (95% confidence interval [CI] 95.3-96.9) falling to 93.2% (95% CI 92.0-94.4) for patients aged 80-84. The one-year postoperative OS among patients aged 75-79 was 86.3% (95% CI 84.7-87.9) compared with 80.5% (95% CI 78.7-82.3) among patients aged 80-84. Five-year OS among patients aged 75-79 was 47.6% (95% CI 46.0-49.2) and 36.6% (95% CI 34.8-38.4) among patients aged 80-84, compared with 61.7% (95% CI 60.9-62.5) among younger patients (<75 years old). Survival among elderly CRC patients (≥75 years old) was in general fairly good when compared with younger patients, especially among patients aged 75-79 and 80-84 with localized or locally advanced disease.

Recent Advances on the Differences between Left- and Right-sided Colorectal Cancer / 中国医学科学院学报

Right-sided colon cancer and left-sided colorectal cancer have significant differences in epidemiology,clinical features,tumor differentiation,response to treatment,prognosis,and molecular characteristics.The former has lower prevalence than the latter and is mainly associated with female and elderly patients,with poor tumor differentiation,strong invasion,poor prognosis,and weak response to epidermal growth factor receptor inhibitors.Thus,it is generally believed that the primary location of colorectal cancer is closely associated with prognosis,acting as an independent prognostic factor for therapeutic efficacy.Recent studies have revealed the genetic differences between right-sided colon cancer and left-sided colorectal cancer,providing explanations for the biological differences.This review summarizes the recent advances on the differences between left-and right-sided colorectal cancer.

Tumour sidedness and clinicopathological features of resected colon cancer in rural population of Northern Pakistan: single institutional analysis / Lateralidade tumoral e características clínico-patológicas do câncer de cólon ressecado na população rural do norte do Paquistão: análise em uma única instituição

ABSTRACT Objectives: Different clinicopathological and molecular features have been demonstrated between right and left sided colon cancers. We aimed to characterize colon cancer and sidedness among a North-Pakistani rural population diagnosed with colon cancer in our institution. Methods: Seventy patients were included in the study that received adjuvant chemotherapy at Bannu Institute of Nuclear Medicine Oncology and Radiotherapy) Bannu, Pakistan from January 2014 to December 2017. Chi-square test was used for significance of categorical variables. p-Values less than 0.05 were considered significant. Results: Mean age at diagnosis for right side colon cancer patients was 43.94 years and for left side colon cancer, it was 49.83 with no significant difference. Male patients were presented more with right (77% vs. 54%, p = 0.044) and females with predominantly left sided tumours i.e. (46% vs. 23%, p = 0.044). Right sided cancer tended to be more poorly differentiated (20% vs. 0%, p = 0.020). Mucinous adenocarcinoma was seen mostly in right sided colon cancer (37% vs. 3%, p ≤ 0.001). There were more locally advanced presentation of right side colon cancer with more node positive (83% vs. 60%, p = 0.025) and lymphovascular invasion (51% vs. 37%, p = 0.016). Sigmoid colon was the most common tumour subsite involved. Conclusion: Our study is the first report of colon cancer in a rural population in North-Pakistan. An earlier onset of tumours (44-50 years) was observed in comparison with global data.

RESUMO Objetivo: Características clínico-patológicas e moleculares distintas foram observadas em tumores de cólon no lado direito ou esquerdo. O presente estudo teve como objetivo caracterizar o câncer de cólon e sua lateralidade em uma população rural norte-paquistanesa diagnosticada com câncer de cólon nesta instituição. Métodos: O estudo incluiu 70 pacientes que foram submetidos a quimioterapia adjuvante no Instituto Bannu de Medicina Nuclear Radioterapia Oncológica (BINOR), Bannu, Paquistão, entre janeiro de 2014 e dezembro de 2017. O teste qui-quadrado foi utilizado para mensurar a significância das variáveis categóricas. Valores de p menores que 0,05 foram considerados significativos. Resultados: A média de idade ao diagnóstico entre pacientes com câncer de cólon no lado direito foi de 43,94 anos e entre aqueles com câncer de cólon no lado esquerdo, 49,83, sem diferença significativa. Os pacientes do sexo masculino apresentaram mais tumores no lado direito (77% vs. 54%, p = 0,044) e as pacientes do sexo feminino apresentaram mais tumores no lado esquerdo (46% vs. 23%, p = 0,044). Tumores mal diferenciados foram mais comumente observados no lado direito (20% vs. 0%, p = 0,020). Adenocarcinoma mucinoso foi observado principalmente em casos de tumores no lado direito (37% vs. 3%, p ≤ 0,001). A apresentação local estava mais avançada em tumores de cólon no lado direito, com mais linfonodos positivos (83% vs. 60%, p = 0,025) e invasão linfovascular (51% vs. 37%, p = 0,016). O cólon sigmoide foi o sublocal mais comum. Conclusão: O presente estudo é o primeiro relato de câncer de cólon em uma população rural no norte do Paquistão. Em comparação com dados globais, observou-se um surgimento mais precoce dos tumores (44-50 anos).

Prognostic factors of patients with stagesI - III left-sided versus rightsided colon cancer receiving radical surgery / 肿瘤

Objective: To investigate the prognostic factors of patients with stages I-III left-sided colon cancer (LCC) versus right-sided colon cancer (RCC) receiving radical surgery. Methods: A retrospective analysis of clinical data from 332 patients with stages I-III colorectal cancer (CRC) who underwent radical surgery in Anhui Provincial Hospital, Anhui Medical University between February 2008 and February 2012 was conducted. The differences in clinicopathological characteristics by tumor location (RCC vs LCC) were examined by using χ2 test. The comparisons of overall 5-year survival rate between RCC and LCC within each stage and for all stages were done by using Kaplan-Meier method. The univariate analysis of prognosis was performed by using log-rank test, and the multivariate analysis was performed by using COX regression model. Results: The overall 5-year survival rate of all patients was 69.9%. The LCC patients had significantly higher overall 5-year survival rate than RCC patients (72.6% vs 66.9%, P = 0.020). The stage III LCC patients had significantly higher overall 5-year survival rate than the stage III RCC patients (62.5% vs 52.2%, P = 0.018), but no significant difference in overall 5-year survival rate was found between stage I or II RCC and LCC patients (P > 0.05). There were significant differences in T stage, histologic type, degree of differentiation, tumor size, hemoglobin, albumin, fibrinogen and carcinoembryonic antigen (CEA) between RCC and LCC patients (all P < 0.05). The univariate analysis showed that tumor location, T stage, N stage, histologic type, degree of differentiation, tumor size, hemoglobin, albumin, fibrinogen and CEA were significantly correlated with overall 5-year survival rate of CRC patients (all P < 0.05). Multivatiate analysis showed that N stage, histologic type, degree of differentiation, hemoglobin, albumin, fibrinogen and CEA were independent prognostic factors of CRC (all P < 0.05). Conclusion: For patients with stages I-III CRC treated with radical surgery, the factors of higher tumor N stage, mucinous adenocarcinoma/signet ring cell carcinoma, poorly differentiated carcinoma, anemia, hypoproteinemia, fibrinogen level more than 4 g/L and CEA level more than 10 ng/mL indicate a poor prognosis. The significant differences in clinicopathological characteristics and prognosis are found between RCC and LCC, but the tumor location is not an independent prognostic factor.

Comparison and treatment of left-and right-side colon cancer / 中国肿瘤临床

Colorectal cancer is one of the most common malignancies. Various studies have focused on differences between colon can-cers on the left and right sides. These types of colon cancer differ in terms of their molecular features, embryologic origin, anatomy, pathogenesis to physiological functions, clinical features, treatment response, and prognosis. Therefore, the left-and right-side colon cancers are regarded as different diseases. These differences have significant effect on clinical decision-making and personalized medi-cine.

Research progress on differences between left-and right-sided colon cancers / 中国肿瘤临床

In recent years, the incidence and mortality of colorectal cancer have gradually increased in China. This review sum-marized the differences in pathogenic factors, clinical manifestations, pathological features, gene expression, therapeutic modalities, and other aspects between left-and right-sided colon cancers. Results showed that the onset of both left-and right-sided colon cancers is associated with gender and age. Significant differences existed among the clinical manifestations and pathological features. Differenc-es in gene expression, allelic deletion, and DNA mismatch repair affected the occurrence, metastasis, and prognosis of left-and right-sided colon cancers. Moreover, the location of primary tumor is a potential predictor of targeted drug efficacy. Differences in survival rates are possibly related to TNM stage. Hence, new ideas for individualized treatment should be provided by analyzing the differences between left-and right-sided colon cancers.

Experimental study of HSP27 differential expression in left sided colon cancer and right sided colon cancer / 中南大学学报(医学版)

Objective To provide molecular genetic basis for oncobiological difference in left sided colon cancer and right sided colon cancer. Differentially expressed proteins in left sided colon cancer and right sided colon cancer were screened by proteomic technique. Methods Tissue samples including left sided colon cancer and right sided colon cancer were collected and preserved in the -80℃ refrigerator. In the first part of our experiment, protein was separated by 2-dimensional gel electrophoresis (2-DE) and the images of the gels were acquired by the scanner and then analyzed to find the differentially expression protein-spots in different groups. The peptide mass fingerprintings (PMF) was acquired by matrix assisted laser desorptiorn/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and the proteins were identified by data searching in the Mascotdatabase. Differentially expressed proteins were assayed by RT-PCR, Western blot, and immunohistochemical method. Results Altogether 55 differentially expressed protein spots were screened and 21 spots of them were identified. Compared with the right sided colon cancer, 14 proteins were up-regulated and 7 proteins down-regulated including HSP27 in the left sided colon cancer. HSP27 expressed higher in the right sided colon cancer than in the left sided colon cancer.Conclusion There are differentially expressed proteins in left sided colon cancer and right sided colon cancer, especially difference in HSP27 expression at mRNA and protein level, which may be molecular genetic basis for oncobiological difference in left sided colon cancer and right sided colon cancer.