Management of obstructed colorectal carcinoma in an emergency setting:An update

Colorectal carcinoma is common,particularly on the left side.In 20%of patients,obstruction and ileus may be the first clinical manifestations of a carcinoma that has advanced(stage II,III or even IV).Diagnosis is based on clinical presentation,plain abdominal radiogram,computed tomography(CT),CT colonography and positron emission tomography/CT.The best management strategy in terms of short-term operative or interventional and long-term oncological outcomes re-mains unknown.For the most common left-sided obstruction,the first choice should be either emergency surgery or endoscopic decompression by self-expen-dable metal stents or tubes.The operative plan should be either one-stage or two-stage resection.One-stage resection with on-table bowel decompression and irrigation can be accompanied or not accompanied by proximal defunctioning stoma(colostomy or ileostomy).Primary anastomosis is more convenient but has increased risks of anastomotic leakage and morbidity.Two-stage resection(Hart-mann’s procedure)is safer and the most widely used despite temporally affecting quality of life.Damage control surgery in high-risk frail patients is less frequently performed since it can be successfully substituted with endoscopic stenting or tubing.For the less common right-sided obstruction,one-stage surgical resection is more beneficial than endoscopic decompression.The role of minimally invasive surgery(laparoscopic or robotic)is a subject of debate.Emergency laparoscopic-assisted management is advantageous to some extent but requires much expertise due to inherent difficulties in dissecting the distended colon and the risk of rup-ture and subsequent septic complications.The decompressing stent as a bridge to elective surgery more substantially decreases the risks of morbidity and mortality than emergency surgery for decompression and has equivalent medium-term overall survival and disease-free survival rates.Its combination with neoadjuvant chemotherapy or radiation may have a positive effect on long-term oncological outcomes.Management plans are crucial and must be individualized to better fit each case.Core Tip:Acute obstruction is common in patients with more advanced colorectal carcinoma and may be the first manifestation mainly of left-sided obstruction and in elderly individuals.Emergency decompression is mandatory.Emergency surgical resection and primary anastomosis accompanied or not accompanied by proximal defunctioning stoma must be the first treatment choice for fit patients under 70 years.Hartmann’s two-stage procedure,although more preferable,must be the second alternative choice.Emergency endoscopic self-expendable metal stents must be preferred in unfit patients as a bridge to surgery and for palliative treatment in all inoperable cases.However,these basic management principles constitute a general direction.Decision-making is important and should be individualized.

GLI1 and PTTG1 expression in colorectal carcinoma patients undergoing radical surgery and their correlation with lymph node metastasis

BACKGROUND Few studies have investigated the expression of GLI1 and PTTG1 in patients undergoing radical surgery for colorectal carcinoma(CRC)and their association with lymph node metastasis(LNM).Therefore,more relevant studies and analyses need to be conducted.AIM To explore GLI1 and PTTG1 expression in patients undergoing radical surgery for CRC and their correlation with LNM.METHODS This study selected 103 patients with CRC admitted to our hospital between April 2020 and April 2023.Sample specimens of CRC and adjacent tissues were collected to determine the positive rates and expression levels of GLI1 and PTTG1.The correlation of the two genes with patients’clinicopathological data(e.g.,LNM)was explored,and differences in GLI1 and PTTG1 expression between patients with LNM and those without were analyzed.Receiver operating characteristic(ROC)curves were plotted to evaluate the predictive potential of the two genes for LNM in patients with CRC.RESULTS Significantly higher positive rates and expression levels of GLI1 and PTTG1 wereobserved in CRC tissue samples compared with adjacent tissues.GLI1 and PTTG1 were strongly linked to LNM in patients undergoing radical surgery for CRC,with higher GLI1 and PTTG1 levels found in patients with LNM than in those without.The areas under the ROC curve of GLI1 and PTTG1 in assessing LNM in patients with CRC were 0.824 and 0.811,respectively.CONCLUSION GLI1 and PTTG1 expression was upregulated in patients undergoing radical surgery for CRC and are significantly related to LNM in these patients.Moreover,high GLI1 and PTTG1 expression can indicate LNM in patients with CRC undergoing radical surgery.The expression of both genes has certain diagnostic and therapeutic significance.

Influence of reduced-port laparoscopic surgery on perioperative indicators, postoperative recovery, and serum inflammation in patients with colorectal carcinoma

BACKGROUND Conventional five-port laparoscopic surgery,the current standard treatment for colorectal carcinoma(CRC),has many disadvantages.AIM To assess the influence of reduced-port laparoscopic surgery(RPLS)on perioperative indicators,postoperative recovery,and serum inflammation indexes in patients with CRC.METHODS The study included 115 patients with CRC admitted between December 2019 and May 2023,52 of whom underwent conventional five-port laparoscopic surgery(control group)and 63 of whom underwent RPLS(research group).Comparative analyses were performed on the following dimensions:Perioperative indicators[operation time(OT),incision length,intraoperative blood loss(IBL),and rate of conversion to laparotomy],postoperative recovery(first postoperative exhaust,bowel movement and oral food intake,and bowel sound recovery time),serum inflammation indexes[high-sensitivity C-reactive protein(hs-CRP),tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6)],postoperative complications(anastomotic leakage,incisional infection,bleeding,ileus),and therapeutic efficacy.RESULTS The two groups had comparable OTs and IBL volumes.However,the research group had a smaller incision length;lower rates of conversion to laparotomy and postoperative total complication;and shorter time of first postoperative exhaust,bowel movement,oral food intake,and bowel sound recovery;all of which were significant.Furthermore,hs-CRP,IL-6,and TNF-αlevels in the research group were significantly lower than the baseline and those of the control group,and the total effective rate was higher.CONCLUSION RPLS exhibited significant therapeutic efficacy in CRC,resulting in a shorter incision length and a lower conversion rate to laparotomy,while also promoting postoperative recovery,effectively inhibiting the inflammatory response,and reducing the risk of postoperative complications.

Hsa_circ_0136666 mediates the antitumor effect of curcumin in colorectal carcinoma by regulating CXCL1 via miR-1301-3p

BACKGROUND This study investigate the anti-tumor effect of curcumin and whether its mediated by hsa_circ_0136666 through miR-1301-3p/CXCL1 in colorectal carcinoma(CRC).Through multiple experiments,we have drawn the conclusion that curcumin inhibited CRC development through the hsa_circ_0136666/miR-1301-3p/CXCL1 axis,hinting at a novel treatment option for curcumin to prevent CRC development.AIM To determine whether hsa_circ_0136666 involvement in curcumin-triggered CRC progression was mediated by sponging miR-1301-3p.METHODS Cell counting kit-8,colony-forming cell,5-ethynyl-2’-deoxyuridine,and flow cytometry assays were carried out to determine cell proliferation,apoptosis,and cell cycle progression.Real-time quantitative polymerase chain reaction quantified hsa_circ_0136666,miR-1301-3p,and chemokine(C-X-C motif)ligand 1(CXCL1),and western blot analysis determined CXCL1,B-cell lymphoma-2(Bcl-2),and Bcl-2 related X protein(Bax)protein levels.CircBank or starbase software was first used for the prediction of miR-1301-3p binding with hsa_circ_0136666 and CXCL1,followed by RNA pull-down,RNA immunoprecipitation,and dualluciferase reporter assay validation.In vivo experiments were implemented in a murine xenograft model.RESULTS Curcumin blocked CRC cell proliferation but boosted apoptosis.Moreover,elevated hsa_circ_0136666 Levels were observed in CRC cells,which were reduced by curcumin.In vitro,hsa_circ_0136666 overexpression abolished the antitumor activity of CRC cells.Mechanical analysis revealed the ability of hsa_circ_0136666 to sponge miR-1301-3p to modulate CXCL1 levels.CONCLUSION Curcumin inhibited CRC development through the hsa_circ_0136666/miR-1301-3p/CXCL1 axis,hinting at a novel treatment option for curcumin to prevent CRC development.

Comprehensive next-generation sequencing reveals double primary colorectal carcinoma missed by diagnostic imaging: A case report

BACKGROUND Multiple primary colorectal carcinoma(MPCC)is a rare clinical disease,which is challenging to differentiate from metastatic disease using histopathological methods.Next-generation sequencing(NGS)has been employed to identify multiple primary cancers.CASE SUMMARY This study a rare case of a 63-year-old male patient diagnosed with MPCC by targeted NGS,which was initially missed by radiological evaluation.The patient was found to have two tumors located on the surface of the colorectum which had distinct genomic alterations.Based on wild-type KRAS detected in the unresected tumor,the patient benefited from the epidermal growth factor receptor(EGFR)inhibitor cetuximab treatment,but developed novel mutations including KIF5B-RET fusion,which provides a possible resistance mechanism to anti-EGFR therapy.CONCLUSION Our case highlights the necessity of using genetic testing for primary tumor diagnosis and the application of serial plasma circulating tumor DNA profiling for dynamic disease monitoring.

Systematic functional interrogation of genome-wide association studies locus 17p13.3 deciphered role and genetic control of FAM57A in colorectal cancer development

Objective:Genome-wide association studies(GWAS)have identified over 150 risk loci linked to colorectal cancer(CRC),including the 17p13.3 locus with the tag single nucleotide polymorphism(SNP)rs12603526 in the Asian population.However,the specific causal gene and the functional regulatory mechanisms in this region remain unresolved,necessitating further investigation to elucidate the underlying mechanisms of CRC.Methods:We employed an RNA interference-based functional approach to identify genes critical for CRC cell proliferation at the GWAS locus 17p13.3.Bioinformatic fine-mapping analysis was conducted to prioritize causal variants.A large-scale study involving 7,013 cases and 7,329 controls from a Chinese population,along with another cohort of 5,158 cases and 20,632 controls from the UK Biobank,was performed to validate the association between the candidate variant and the gene.A series of biological experiments was conducted to explore the function of the candidate gene and its regulatory mechanisms.Results:We identified FAM57A as a key oncogene that promotes CRC cell proliferation,and confirmed its carcinogenic role through in vitro proliferation assays.The variant rs526835 was prioritized as a causal candidate for CRC risk,located in a functional region with enhancer properties,and showed a significant quantitative association with FAM57A expression.The rs526835[T]variant was associated with a 1.17-fold increase in CRC risk[95%confidence interval(95%CI):1.11−1.23,P=1.23×10−9]in the large-scale Chinese cohort,which was further corroborated in the UK Biobank cohort.Mechanistically,we demonstrated that rs526835 enhances a promoterenhancer interaction mediated by the transcription factor JUN,leading to increased expression of FAM57A.Conclusions:We reveal the underlying mechanisms of CRC predisposition at the GWAS locus 17p13.3.Additionally,our findings highlight the critical role of FAM57A in CRC pathogenesis and introduce a novel enhancer-promoter interaction between FAM57A and rs526835,which could inform future precision prevention and personalized cancer therapies.

Adenocarcinoma of sigmoid colon with metastasis to an ovarian mature teratoma: A case report

BACKGROUND Colorectal cancer ranks third in global cancer-related mortality,often due to metastases to liver and lungs.Ovarian metastases are less common,accounting for 3.6%to 7.4%of cases.In contrast,mature ovarian teratomas are frequently benign.Tumor-to-tumor metastasis is a rare phenomenon,with a limited number of documented cases.Three cases of mature ovarian teratomas metastasizing from different cancers have been reported.This report focuses on a case of tumor-totumor metastasis from sigmoid colon adenocarcinoma to a mature ovarian teratoma.CASE SUMMARY A 41-year-old Taiwan residents woman with no known systemic diseases presented with lower back pain,which led to imaging revealing malignant lesions in the spine,pelvis,liver,and multiple lung metastases.She was diagnosed with sigmoid colon adenocarcinoma with metastases to the liver,lung,bone,and a left ovarian teratoma.Treatment involved radiotherapy and chemotherapy,resulting in regression of the primary tumor and stable lung and liver lesions.Due to abdominal symptoms,she underwent exploratory surgery,unveiling a mature teratoma in the left ovary with signs of metastatic adenocarcinoma.CONCLUSION Consider resecting mature ovarian teratomas with concurrent colorectal adenocarcinoma to prevent tumor-to-tumor metastasis.

KRAS and BRAF gene mutations and DNA mismatch repair status in Chinese colorectal carcinoma patients

AIM:To investigate gene mutations and DNA mismatch repair(MMR) protein abnormality in Chinese colorectalcarcinoma(CRC) patients and their correlations with clinicopathologic features.METHODS:Clinical and pathological information for 535 patients including 538 tumors was reviewed and recorded.Mutation analyses for exon 2 of KRAS gene and exon 15 of BRAF gene were performed by Sanger sequencing except that in 9 tumors amplification refractory mutation system PCR was used.Expression of MMR proteins including MHL1,MSH2,MSH6 and PMS2 was evaluated by immunohistochemistry.Correlations of KRAS and BRAF mutation status and the expression status of MMR proteins with age,gender,cancer stage,location,and histology were analyzed.Correlations between KRAS or BRAF mutations and MMR protein expression were also explored.RESULTS:The overall frequencies of KRAS and BRAF mutations were 37.9% and 4.4%,respectively.KRAS mutations were more common in patients ≥ 50 years old(39.8% vs 22% in patients < 50 years old,P < 0.05).The frequencies of BRAF mutants were higher in tumors from females(6.6% vs males 2.8%,P < 0.05),located in the right colon(9.6% vs 2.1% in the left colon,1.8% in the rectum,P < 0.01),with mucinous differentiation(9.8% vs 2.8% without mucinous differentiation,P < 0.01),or being poorly differentiated(9.5% vs 3.4% well/moderately differentiated,P < 0.05).MMR deficiency was strongly associated with proximal location(20.5% in the right colon vs 9.2% in the left colon and 5.1% in the rectum,P < 0.001),early cancer stage(15.0% in stages Ⅰ-Ⅱ vs 7.7% in stages Ⅲ-Ⅳ,P < 0.05),and mucinous differentiation(20.2% vs 9.2% without mucin,P < 0.01).A higher frequency of MLH1/PMS2 loss was found in females(9.2% vs 4.4% in males,P < 0.05),and MSH2/MSH6 loss tended to be seen in younger(<50 years old) patients(12.0% vs 4.0% ≥ 50 years old,P < 0.05).MMR deficient tumors were less likely to have KRAS mutations(18.8% vs 41.7% in MMR proficient tumors,P < 0.05) and tumorswith abnormal MLH1/PMS2 tended to harbor BRAF mutations(15.4% vs 4.2% in MMR proficient tumors,P < 0.05).CONCLUSION:The frequency of sporadic CRCs having BRAF mutation,MLH1 deficiency and MSI in Chinese population may be lower than that in the Western population.

Clinicopathologic and immunohistochemical profile of ovarian metastases from colorectal carcinoma

Metastasis of colorectal adenocarcinoma of the ovary is not an uncommon occurrence and ovarian metastases from colorectal carcinoma frequently mimic endometrioid and mucinous primary ovarian carcinoma.The clinical and pathologic features of metastatic colorectal adenocarcinoma involving the ovary is reviewed with particular focus on the diagnostic challenge of distinguishing these secondary ovarian tumors from primary ovarian neoplasm.Immunohistochemical stains that may be useful in the differential diagnosis of metastatic colorectal tumors to the ovary and primary ovarian tumors are detailed.

Semaphorin 4D and hypoxia-inducible factor-1α overexpression is related to prognosis in colorectal carcinoma

AIM:To investigate semaphorin 4D(Sema4D)and hypoxia-inducible factor-1α(HIF-1α)expression in colorectal carcinoma and evaluate their clinicopathological and prognostic significance.METHODS:Eighty-six curatively resected colorectal carcinoma patients at different stages of disease were randomly selected from the group of patients who underwent surgery,and none of them received preoperative radiochemotherapy.Normal proximal adjacent bowel tissue,which served as an internal control,was obtained from 52 randomly selected patients.Immunohistochemistry was performed to analyze the expression of Sema4D and the tumor angiogenesisrelated protein HIF-1αin normal colorectal tissues and colorectal carcinoma tissues.The relationships between the expression and clinical characters and prognosis were analyzed.RESULTS:HIF-1αand Sema4D were positively expressed in 58%and 60%of colorectal carcinoma tissues,respectively.Significantly lower expression levels were observed in normal mucosa(8%and 12%,respectively).HIF-1αand Sema4D expression was closely correlated with histological tumor type,tumornode-metastasis(TNM)stage,and lymphatic metastasis(P<0.05),but not with age or tumor size(P>0.05).HIF-1αand Sema4D protein expression was significantly correlated with prognosis of colorectal carcinoma,as determined by Spearman rank correlation analysis(r=0.567;P<0.01).Multivariate Cox analysis revealed that only Sema4D expression played a significant role in predicting patient prognosis(P<0.05).CONCLUSION:These findings suggest that HIF-1αand Sema4D expression correlates with histological tumor type,TNM stage,and lymphatic metastasis in colorectal carcinoma and that Sema4D is a prognostic indicator of colorectal carcinoma.

Differential mucin phenotypes and their significance in a variation of colorectal carcinoma

AIM: To investigate mucin expression profiles in colorectal carcinoma (CRC) histological subtypes with regard to clinicopathologic variables and prognosis. METHODS: Mucin (MUC)2 and MUC5AC expressions were assessed by immunohistochemistry for a total of 250 CRC cases that underwent surgical resection. CRCs included 63 well-to-moderately differentiated adenocar-cinomas (WMDAs), 91 poorly differentiated adenocarcinomas (PDAs), 81 mucinous adenocarcinoma (MUAs), and 15 signet-ring cell carcinomas (SRCCs). MUC2 and MUC5AC were scored as positive when ≥ 25% and ≥ 1% of cancer cells were stained positive, respectively. The human mutL homolog 1 and human mutS homolog 2 expressions were assessed by immunohistochemistry in PDAs to investigate mismatch-repair (MMR) status.Tumors that did not express either of these two were considered MMR-deficient. Results were analyzed for associations with clinicopathologic variables and the prognosis in individual histological CRC subtypes. RESULTS: MUC2-positive and MUC5AC-positive WMDA percentages were 49.2% and 30.2%, respectively. In contrast, MUC2-positive and MUC5AC-positive PDA percentages were 9.5% and 51.6%, respectively. MUC2 levels tended to decrease and MUC5AC levels tended to increase from WMDA to PDA. In 21 tumors comprising both adenoma and adenocarcinoma components in a single tumor (4 WMDAs, 7 PDAs, and 10 MUAs), MUC2 was significantly downregulated in PDA and MUC5AC was downregulated in PDA and MUA in the adenoma-carcinoma sequence. These results suggested that MUC2 levels might be associated with malignant potential and that MUC5AC expression was an early event in tumorigenesis. Despite worse prognoses than WMDA, high MUC2 expression levels were maintained in MUA (95.1%) and SRCC (71.5%), which suggested a pathogenesis for these subtypes distinct from that of WMDA. No significant associations were found between MUC2 expression and any clinicopathologic variables in any histological subtype. MUC5AC expression in PDA was closely associated with right-sided location (P = 0.017), absence of nodal metastasis (P = 0.010), low tumor node metastasis stage (P = 0.010), and MMR deficiency (P = 0.003). MUC2 expression in WMDA was a marginal prognostic factor for recurrence/metastasis-free survival (RFS) by univariate Cox analysis (P = 0.077) but not by multivariate Cox analysis (P = 0.161). MUC5AC expression in PDA was a significant prognostic factor for RFS by univariate Cox analysis (P = 0.007) but not by multivariate Cox analysis (P = 0.104). Kaplan-Meier curves and log-rank tests revealed that MUC2 expression was marginally associated with a better WMDA prognosis [P = 0.064 for RFS and P = 0.172 for overall survival (OS)] but not for PDA. In contrast, MUC5AC expression was significantly and marginally associated with a better PDA prognosis in terms of RFS and OS, respectively(P = 0.004 for RFS and P = 0.100 for OS), but not for WMDA and MUA. CONCLUSION: Mucin core protein expression profiles and clinical significance differ according to histological CRC subtypes. This may reflect different pathogeneses for these tumors.

miRNA-338-3p suppresses cell growth of human colorectal carcinoma by targeting smoothened

AIM:To investigate the regulative effect of miRNA-3383p(miR-338-3p) on cell growth in colorectal carcinoma(CRC).METHODS:The lentiviral vector pLV-THM-miR-338-3p and pLV-THM-miR-338-3p-inhibitor were constructed.The recombinant viral vector encoding the pre-miR338-3p or miR-338-3p-inhibitor and the two packaging plasmids psPAX2 and pMD2.G were cotransfected into human embryonic kidney 293T cells to package lentivirus.The supernatant containing the lentivirus particles was harvested to determine the viral titer,and this supernatant was then used to transduce CRCderived cell line,SW-620.Flow cytometry was utilized for sorting the green fluorescent protein(GFP) + cells to establish the SW-620 cell line stably expressing premiR-338-3p or miR-338-3p-inhibitor.Moreover,the expression of miR-338-3p was determined by real-time reverse transcriptase polymerase chain reaction,andWestern blotting was used to detect the expression of the smoothened(SMO,the possible target of miR-3383p) protein in SW-620 cells.Furthermore,the status of CRC cell proliferation and apoptosis were detected by 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide assay and flow cytometry,respectively.RESULTS:Restriction enzyme digestion and DNA sequencing demonstrated that the lentiviral vector pLVTHM-miR-338-3p and pLV-THM-miR-338-3p-inhibitor were constructed successfully.GFP was expressed after the SW-620 cells were transduced by the lentivirus.Expression of miR-338-3p in SW-620 cells transduced with the lentivirus pLV-THM-miR-338-3p was significantly increased(relative expression 3.91 ± 0.51 vs 2.36 ± 0.44,P < 0.01).Furthermore,overexpression of miR-338-3p inhibited the expression of SMO protein in SW-620 cells,which showed obviously suppressed proliferation ability [cellular proliferation inhibition rate(CPIR) 61.9% ± 5.2% vs 41.6% ± 4.8%,P < 0.01].Expression of miR-338-3p in SW-620 cells transduced with the lentivirus pLV-THM-miR-338-3p-inhibitor was significantly decreased(relative expression 0.92 ± 0.29 vs 2.36 ± 0.44,P < 0.01).Moreover,the downregulated expression of miR-338-3p caused upregulated expression of the SMO protein in SW-620 cells,which showed significantly enhanced proliferation ability(CPIR 19.2% ± 3.8% vs 41.6% ± 4.8%,P < 0.01).However,anti-SMO-siRNA largely,but not completely,reversed the effects induced by blockage of miR-338-3p,suggesting that the regulative effect of miR-338-3p on CRC cell growth was indeed mediated by SMO.CONCLUSION:miR-338-3p could suppress CRC growth by inhibiting SMO protein expression.

New cancer suppressor gene for colorectal adenocarcinoma:Filamin A

AIM:To determine the expression and significance of filamin A(FLNa)in colorectal adenocarcinoma tissue.METHODS:The expression of FLNa in 46 colorectal cancer tissues and normal tissues was detected by immunohistochemistry,reverse transcription polymerase chain reaction(RT-PCR)and Western blotting,and its relationship with clinical parameters and prognosis was analyzed.RESULTS:The positive expression of FLNa in cancer tissues was lower than that in normal mucosa,and the difference was statistically significant.The expression of FLNa correlated with liver metastasis,lymph node metastasis and rectal invasion depth,regardless of sex,age,tumor location,tumor size,gross shape and histological type of colorectal carcinoma.Multivariate analysis showed that FLNa was an independent risk factor for postoperative survival of patients with colorectal adenocarcinoma.Moreover,survival analysis showed that the expression level of FLNa was closely related with survival of patients with colorectal adenocarcinoma.The results of RT-PCR and Western blotting were consistent with those of immunohistochemistry.CONCLUSION:FLNa showed low expression in colorectal adenocarcinoma,high correlation with the incidence and development of colorectal cancer,and was considered an indicator of prognosis.

Relationship of PARG with PARP,VEGF and b-FGF in Colorectal Carcinoma

Objective： To investigate the relationship of poly（ADP-ribose）glycohydrolase（PARG） with poly （ADP-ribose） polymerase（PARP）, vascular endothelial growth factor （VEGF） and basic fibroblast growth factor（b-FGF） in colorectal carcinoma（CRC）. Methods： Immunohistochemical analysis was used to detect PARG, PARP, VEGF and b-FGF in human colorectal carcinoma. Flow cytometry was used to detect PARG and PARP in murine CT26 cell line. Gallotannin （GLTN） was served as PARG inhibitor. Results： The individual positive rates of PARG, PARE VEGF and b-FGF were 55.81%（24/43）, 97.67%（42/43）, 79.07%（34/43） and 81.40%（35/43）, respectively, which were significantly higher than those of control group. The positive PARG was correlated to PARP（r=0.3703, P〈0.05） and b-FGF （r=0.4838, P〈0.05）. The positive PARP was correlated to VEGF （r=0.3968, P〈0.05） and b-FGF （r=0.5610, P〈0.05）. Both PARG and PARP were expressed in CT26 cells. The positive staining rates of PARG and PARP in GLTN-treated group were 7.3% and 52.38%, respectively. They were markedly reduced than those of control group （55.41% and 95.28%, P〈0.01, n=10000）. Conclusion： The data suggest that PARG expression probably plays a role for VEGF and b-FGF expression in colorectal carcinoma.

Anti-miRNA-221 sensitizes human colorectal carcinoma cells to radiation by upregulating PTEN

AIM:To investigate the regulative effect of miRNA(miR)-221 on colorectal carcinoma(CRC)cell radiosensitivity and the underlying mechanisms.METHODS:A human CRC-derived cell line was cultured conventionally and exposed to different doses of X-rays(0,2,4,6 and 8 Gy).The total RNA and protein of the cells were extracted 24 h after irradiation,and the alteration of miR-221 and phosphatase and tensin homolog deleted on chromosome 10(PTEN)gene mRNA expression was detected by real-time reverse transcriptase polymerase chain reaction(PCR).The protein alteration of PTEN in the cells was detected by Western blotting.Caco2 cells were pretreated with or without anti-PTEN-siRNA prior to the addition of premiR-221 or anti-miR-221 using Lipofectamine 2000.Colony formation assay and flow cytometry analysis were used to measure the surviving cell fraction and the sensitizing enhancement ratio after irradiation.Ad-ditionally,PTEN 3′-untranslated region fragment was PCR amplified and inserted into a luciferase reporter plasmid.The luciferase reporter plasmid construct was then transfected into CRC cells together with premiR-221 or anti-miR-221,and the luciferase activity in the transfected cells was detected.RESULTS:The X-ray radiation dose had a significant effect on the expression of miR-221 and PTEN protein in human Caco2 cells in a dose-dependent manner.The miR-221 expression level improved gradually with the increase in irradiation dose,while the PTEN protein expression level reduced gradually.miR-221 expression was significantly reduced in the anti-miR-221 group compared with the pre-miR-221 and negative control groups(P<0.01).Anti-miR-221 upregulated expression of PTEN protein and enhanced the radiosensitivity of Caco2 cells(P<0.01).Moreover,the inhibitory effect was dramatically abolished by pretreatment with anti-PTEN-siRNA,suggesting that the enhancement of radiosensitivity was indeed mediated by PTEN.A significant increase of luciferase activity was detected in CRC cells that were cotransfected with the luciferase reporter plasmid construct and anti-miR-221(P<0.01).CONCLUSION:Anti-miR-221 can enhance the radiosensitivity of CRC cells by upregulating PTEN.

Histologic features and genomic alterations of primary colorectal adenocarcinoma predict growth patterns of liver metastasis

BACKGROUND Different histological growth patterns(HGPs)of colorectal carcinoma(CRC)liver metastasis are associated with patients’prognosis and response to antiangiogenic therapy.However,the relationship between HGPs of liver metastasis and clinicopathological and genomic characteristics of primary cancer has not been well established.AIM To assess whether certain clinicopathological and genomic features of primary CRC could predict the HGPs of liver metastasis.METHODS A total of 29 patients with paired resections of both primary CRC and liver metastasis were divided into two groups:A(15 cases with desmoplastic liver metastasis)and B(14 cases with replacement liver metastasis).Clinical information was obtained from patients’charts.Mismatch repair proteins,BRAFV600E,and PD-L1 were evaluated by immunohistochemistry.Five cases were selected randomly from each group for whole exome sequencing(WES)analysis.RESULTS In the primary tumor,expanding growth pattern,low tumor budding score(TBS),and Crohn’s disease-like response(CDR)were associated with desmoplastic liver metastasis and better overall survival,whereas infiltrating growth pattern alone of primary carcinoma could predict the replacement liver metastasis and worse overall survival(P<0.05).On WES analysis,primary carcinoma with desmoplastic liver metastasis showed mutations in APC(4/5);TP53(3/5);KRAS,PIK3CA,and FAT4(2/5);BRCA-1,BRCA2,BRAF,and DNAH5(1/5),whereas primary carcinoma with replacement liver metastasis showed mutations in APC and TP53(3/5);KRAS,FAT4,DNH5,SMAD,ERBB2,ERBB3,LRP1,and SDK1(1/5).CONCLUSION The HGPs,TBS,and CDR of primary CRC as well as the presence of specific genetic mutations such as those in PIK3CA could be used to predict the HGPs of liver metastasis,response to therapy,and patients’prognosis.

Epithelial membrane protein 1 negatively regulates cell growth and metastasis in colorectal carcinoma

AIM: To determine the expression and function of epithelial membrane protein 1 (EMP1) in colorectal carcinoma.

CATHEPSIN B EXPRESSION AND ITS RELATIONSHIP WITH MICROVESSEL DENSITY AND BIOLOGICAL BEHAVIOUR OF COLORECTAL CARCINOMA

Objective: To investigate cathepsin B(CB) expression in colorectal carcinoma and its relationship with microvessel density (MVD) and biological behavior. Methods: CB and MVD were detected by immunohistochemistry in 47 cases of colorectal carcinoma. Results: The expression of CB in mucinous colorectal carcinoma was significantly higher than that in no-mucinous colorectal carcinoma. There was significant difference (P<0.05). The MVD in group with positive CB was stronger than that in group with negative CB. There was also significant difference (P<0.05). Conclusion: The results suggest that CB expression has correlation with MVD, invasion and metastasis in colorectal carcinoma, especially in mucinous colorectal carcinoma.

Expression of a novel apoptosis inhibitor-survivin in colorectal carcinoma

AIM： To investigate the role of survivin expression in the pathogenesis of colorectal carcinoma. METHODS： Immunohistochemistry S-P method and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNE） were used to detect the expression of survivin and apoptotic cell in situ in colorectal cancerous tissues, para-cancerous tissues and normal tissues of 48 cases of colorectal carcinoma. RESULTS： The survivin positive unit （PU） was higher in cancerous tissues （38.76±5.14） than in para-cancerous （25.17±7.26） or normal tissues （0.57±0.03） （P〈0.05）. The apoptosis index （AI） of para-cancerous tissues was （7.51±2.63%） higher than cancerous tissues （4.65±1.76%）. The expression of survivin was associated with pathological grade, lymph node metastasis and Dukes stage of colorectal carcinoma. CONCLUSION： Survivin expression may play an important role in carcinogenesis of colorectal carcinoma and may be associated with malignant biological behaviors of colorectal carcinoma.

DNA methylation assay for colorectal carcinoma

Colorectal carcinoma(CRC) is a common cause of morbidity and mortality worldwide. Two pathogenic pathways are involved in the development of adenoma to CRC. The first pathway involves APC/β-catenin characterized by chromosomal instability resulting in the accumulation of mutations. The second pathway is characterized by lesions in DNA mismatch repair genes.Aberrant DNA methylation in selected gene promoters has emerged as a new epigenetic pathway in CRC development. CRC screening is the most efficient strategy to reduce death. Specific DNA methylation events occur in multistep carcinogenesis.Epigenetic gene silencing is a causative factor of CRC development. DNA methylations have been extensively examined in stool from CRC and precursor lesions. Many methylated genes have been described in CRC and adenoma, although no definite DNA methylation biomarkers panel has been established. Multiple DNA methylation biomarkers, including secreted frizzled-related protein 2, secreted frizzled-related protein 1, tissue factor pathway inhibitor 2, vimentin, and methylguanine DNA methyltransferase, have been further investigated, and observations have revealed that DNA methylation biomarkers exhibit with high sensitivity and specificity. These markers may also be used to diagnose CRC and adenoma in early stages. Real time polymerase chain reaction(q PCR) is sensitive, scalable, specific, reliable, time saving, and cost effective. Stool exfoliated markers provide advantages, including sensitivity and specificity. A stool q PCR methylation test may also be an enhanced tool for CRC and adenoma screening.