Long-term outcomes of intraoperative chemotherapy with 5-FU for colorectal cancer patients receiving curative resection (IOCCRC): a randomized, multicenter, prospective, phase III trial.

BACKGROUND: We aimed to compare combined intraoperative chemotherapy and surgical resection with curative surgical resection alone in colorectal cancer patients. METHODS: We performed a multicenter, open-label, randomized, phase III trial. All eligible patients were randomized and assigned to intraoperative chemotherapy and curative surgical resection or curative surgical resection alone (1:1). Survival actualization after long-term follow-up was performed in patients analyzed on an intention-to-treat basis. RESULTS: From January 2011 to January 2016, 696 colorectal cancer patients were enrolled and randomly assigned to intraoperative chemotherapy and radical surgical resection (n=341) or curative surgical resection alone (n=344). Intraoperative chemotherapy with surgical resection showed no significant survival benefit over surgical resection alone in colorectal cancer patients (3-year DFS: 91.1% vs. 90.0%, P=0.328; 3-year OS: 94.4% vs. 95.9%, P=0.756). However, colon cancer patients benefitted from intraoperative chemotherapy, with a relative 4% reduction in liver and peritoneal metastasis (HR=0.336, 95% CI: 0.148-0.759, P=0.015) and a 6.5% improvement in 3-year DFS (HR=0.579, 95% CI: 0.353-0.949, P=0.032). Meanwhile, patients with colon cancer and abnormal pretreatment CEA levels achieved significant survival benefits from intraoperative chemotherapy (DFS: HR=0.464, 95% CI: 0.233-0.921, P=0.029 and OS: (HR=0.476, 95% CI: 0.223-1.017, P=0.049). CONCLUSIONS: Intraoperative chemotherapy showed no significant extra prognostic benefit in total colorectal cancer patients who underwent radical surgical resection; however, in colon cancer patients with abnormal pretreatment serum CEA levels (> 5 ng/ml), intraoperative chemotherapy could improve long-term survival.

Neoadjuvant PD-1 blockade with sintilimab in mismatch-repair deficient, locally advanced rectal cancer: an open-label, single-centre phase 2 study.

BACKGROUND: The current standard treatment for locally advanced rectal cancer is neoadjuvant chemoradiotherapy followed by radical surgery, but this approach can lead to multiple complications. We aimed to investigate the clinical activity and safety of neoadjuvant therapy with sintilimab, a single-agent PD-1 antibody, in patients with mismatch-repair deficient locally advanced rectal cancer. METHODS: This open-label, single-arm, phase 2 study was done at the Sun Yat-sen University Cancer Center, Guangzhou, China. Patients aged 18-75 years with mismatch-repair deficient or microsatellite instability-high locally advanced rectal cancer were enrolled and received neoadjuvant sintilimab monotherapy (200 mg by intravenous infusion) every 21 days. After an initial four cycles of treatment, patients and clinicians could choose one of the following options: total mesorectal excision surgery, followed by four cycles of adjuvant sintilimab with or without CapeOX chemotherapy (capecitabine 1000 mg/m2, orally administered twice daily on days 1-14; oxaliplatin 130 mg/m2, intravenously administered on day 1 every 3 weeks), determined by clinicians; or another four cycles of sintilimab followed by radical surgery or observation (only for patients with a clinical complete response; also known as the watch and wait strategy). The primary endpoint was the complete response rate, which included both a pathological complete response after surgery and a clinical complete response after completion of sintilimab treatment. Clinical response was evaluated by digital rectal examination, MRI, and endoscopy. Response was assessed in all patients who received treatment at least until the first tumour response assessment, after the first two cycles of sintilimab. Safety was analysed in all patients who received at least one dose of treatment. This trial is closed to enrolment and is registered with ClinicalTrials.gov (NCT04304209). FINDINGS: Between Oct 19, 2019, and June 18, 2022, 17 patients were enrolled and received at least one dose of sintilimab. The median age was 50 years (IQR 35-59) and 11 (65%) of 17 patients were male. One patient was excluded from efficacy analyses because they were lost to follow-up after the first sintilimab cycle. Of the remaining 16 patients, six underwent surgery, of whom three had a pathological complete response. Nine other patients had a clinical complete response and chose the watch and wait strategy. One patient had a serious adverse event and discontinued treatment; this patient did not have a complete clinical response and refused to undergo surgery. A complete response was thus noted for 12 (75%; 95% CI 47-92) of 16 patients. One of the three patients who underwent surgery but did not have a pathological complete response showed an increase in tumour volume after the initial four cycles of sintilimab (at which point they underwent surgery); this patient was deemed to have primary resistance to immune checkpoint inhibitors. After a median follow-up of 17·2 (IQR 8·2-28·5) months, all patients were alive and none had disease recurrence. Only one (6%) patient had a grade 3-4 adverse event, which was deemed a serious adverse event (grade 3 encephalitis). INTERPRETATION: The preliminary results of this study suggest that anti-PD-1 monotherapy is effective and tolerable for patients with mismatch-repair deficient locally advanced rectal cancer and could potentially spare some patients from radical surgery. Longer treatment courses might be needed to achieve maximum effects in some patients. Longer follow-up is also needed to observe the duration of response. FUNDING: The National Natural Science Foundation of China, CAMS Innovation Fund for Medical Sciences, Science and Technology Program of Guangzhou, and Innovent Biologics.

Case report: Reproductive organ preservation and subsequent pregnancy for an infertility patient with lynch syndrome-associated synchronous endometrial cancer and colon cancer after treatment with a PD-1 checkpoint inhibitor.

Currently, immune checkpoint inhibitors (ICIs) are the mainstay of treatment for Lynch syndrome patients. However, the tumor regression features in radiology and pathology are inconsistent for patients who are treated with ICIs, which sometimes confuses surgical decision-making. Here, we report a case in which a 36-year-old patient suffering from infertility was diagnosed with Lynch syndrome-associated synchronous endometrial cancer and colon cancer, and persistently enlarged left iliac paravascular lymph nodes were detected after receiving sintilimab treatment, a programmed cell death 1 (PD-1) receptor inhibitor. Fortunately, when she was about to undergo hysterectomy and bilateral salpingo-oophorectomy, intraoperative pathology examination did not reveal any cancer cells in these lymph nodes, and therefore, her reproductive organs were preserved. Later, the patient successfully conceived and gave birth to a healthy male neonate with no immune-related adverse events (irAEs) during an 11-month follow-up. This case indicates that surgeons should carefully inspect the imaging characteristics after immunotherapy and that organ preservation is possible even for patients who fail to achieve complete clinical regression, which is especially important for female patients of childbearing age.

Safety of intraoperative chemotherapy with 5-FU for colorectal cancer patients receiving curative resection: a randomized, multicenter, prospective, phase III IOCCRC trial (IOCCRC).

PURPOSE: The safety and efficacy of intraoperative chemotherapy in colorectal cancer have not yet been extensively investigated. This randomized control trial was designed to compare the safety and efficacy of intraoperative chemotherapy in combination with surgical resection to those of traditional surgical resection alone. METHODS: From January 2011 to January 2016, 696 colorectal cancer patients were enrolled in this study: 341 patients were randomly assigned to the intraoperative chemotherapy, which consist of portal vein chemotherapy, intraluminal chemotherapy and intraperitoneal chemotherapy, plus surgery group, whereas 344 patients were randomized to the control group to undergo surgery alone. Eleven patients withdrew consent. RESULTS: Intraoperative chemotherapy did not increase the rate of surgical complications, and no severe chemotherapy-associated side effects were observed. Four patients in each of the intraoperative chemotherapy and the control groups experienced anastomotic leakage and underwent a second operation (1.2 vs. 1.2%, P = 0.99). There were no deaths within 90 days after surgery in the chemotherapy group, whereas one patient died in the control group. Intraoperative chemotherapy did not decrease the rate of patients who received postoperative chemotherapy between the intraoperative group and control group (29.3 vs. 30.2%, P = 0.795). CONCLUSIONS: Intraoperative chemotherapy can be safely performed during colorectal surgery; however, follow-up is necessary for a better assessment of its efficacy. ClinicalTrial.gov Register Number: NCT01465451.

Bevacizumab with preoperative chemotherapy versus preoperative chemotherapy alone for colorectal cancer liver metastases: a retrospective cohort study.

This study aimed to assess the efficacy and safety of bevacizumab plus preoperative chemotherapy as first-line treatment for liver-only metastatic colorectal cancer in Chinese patients compared with those of preoperative chemotherapy alone.Patients with histologically confirmed liver-only metastatic colorectal cancer were sequentially reviewed, and received either preoperative chemotherapy plus bevacizumab (bevacizumab group, n = 32) or preoperative chemotherapy alone (chemotherapy group, n = 57). Progression-free survival, response rate, liver resection rate, conversion rate, and safety were analyzed.With median follow-up of 28.7 months, progression-free survival was 10.9 months (95% confidence interval: 8.7-13.1 months) in bevacizumab group and 9.9 months (95% confidence interval: 6.8-13.1 months) in chemotherapy group (P = 0.472). Response rates were 59.4% in bevacizumab group and 38.6% in chemotherapy group (P = 0.059). Overall liver resection (R0, R1, and R2) rate was 68.8% in bevacizumab group and 54.4% in chemotherapy group (P = 0.185). Conversion rate was 51.9% in bevacizumab group and 40.4% in chemotherapy group (P = 0.341). No postoperative complication was observed in all patients.Bevacizumab plus preoperative chemotherapy as first-line treatment for liver-only metastatic colorectal cancer tends to achieve better clinical benefit with controllable safety in Chinese patients.

Surgery with versus without preoperative concurrent chemoradiotherapy for mid/low rectal cancer: an interim analysis of a prospective, randomized trial.

INTRODUCTION: Multimodality therapy, including preoperative chemoradiotherapy (CRT) and total mesorectal excision (TME), has effectively reduced local recurrence rates of rectal cancer over the past decade. However, the benefits and risks of the addition of neoadjuvant CRT to surgery need to be evaluated. This study was to compare the efficacy of TME with versus without preoperative concurrent chemoradiotherapy (CCRT) involving XELOX regimen (oxaliplatin plus capecitabine) in Chinese patients with stages II and III mid/low rectal adenocarcinoma. METHODS: We randomly assigned patients to the TME group (TME without preoperative CCRT) or CCRT + TME group (TME with preoperative CCRT). The primary endpoint was disease-free survival (DFS); the secondary endpoints were overall survival (OS), local and distant recurrence, tumor response to CRT, toxicity, sphincter preservation, and surgical complications. An interim analysis of the potential inferiority of DFS in the CCRT + TME group was planned when the first 180 patients had been followed up for at least 6 months. RESULTS: A total of 94 patients in the TME group and 90 patients in the CCRT + TME group were able to be evaluated. The 3-year DFS and OS rates were 86.3 % and 91.5 % in the whole cohort, respectively. The 3-year DFS rates of the TME and CCRT + TME groups were 85.7% and 87.9 % (P = 0.766), respectively, and the 3-year OS rates were 90.7 % and 92.3 % (P = 0.855), respectively. The functional sphincter preservation rates of the TME and CCRT + TME groups were 71.3 % and 70.0 % (P = 0.849), respectively. In the TME group, 16 (17.0 %) patients were proven to have pTNM stage I disease after surgery. In the CCRT + TME group, 32 (35.6 %) patients achieved a pathologic complete response (pCR). CONCLUSIONS: Preliminary results indicated no significant differences in the DFS, OS, or functional sphincter preservation rates between the TME and CCRT + TME groups. However, preoperative CCRT with XELOX yielded a high pCR rate. Newer techniques are needed to improve the staging accuracy, and further investigation is warranted. CLINICAL TRIAL REGISTRATION NUMBER: Chi CTR-TRC-08000122.

Intraoperative blood loss independently predicts survival and recurrence after resection of colorectal cancer liver metastasis.

BACKGROUND: Although numerous prognostic factors have been reported for colorectal cancer liver metastasis (CRLM), few studies have reported intraoperative blood loss (IBL) effects on clinical outcome after CRLM resection. METHODS: We retrospectively evaluated the clinical and histopathological characteristics of 139 patients who underwent liver resection for CRLM. The IBL cutoff volume was calculated using receiver operating characteristic curves. Overall survival (OS) and recurrence free survival (RFS) were assessed using the Kaplan-Meier and Cox regression methods. RESULTS: All patients underwent curative resection. The median follow up period was 25.0 months (range, 2.1-88.8). Body mass index (BMI) and CRLM number and tumor size were associated with increased IBL. BMI (P=0.01; 95% CI = 1.3-8.5) and IBL (P<0.01; 95% CI = 1.6-12.5) were independent OSOs predictors. Five factors, including IBL (P=0.02; 95% CI = 1.1-4.1), were significantly related to RFS via multivariate Cox regression analysis. In addition, OSOs and RFS significantly decreased with increasing IBL volumes. The 5-year OSOs of patients with IBL≤250, 250-500, and >500mL were 71%, 33%, and 0%, respectively (P<0.01). RFS of patients within three IBL volumes at the end of the first year were 67%, 38%, and 18%, respectively (P<0.01). CONCLUSIONS: IBL during CRLM resection is an independent predictor of long term survival and tumor recurrence, and its prognostic value was confirmed by a dose-response relationship.

Hospital-based colorectal cancer survival trend of different tumor locations from 1960s to 2000s.

BACKGROUND: Our aim is to explore the trend of association between the survival rates of colorectal cancer (CRC) and the different clinical characteristics in patients registered from 1960s to 2000s. We hypothesized that the survival rate of CRC increases over time and varies according to anatomic subsites. METHODS: Information from a total of 4558 stage T(1-4)N(1-2)M0 CRC patients registered from 1960s to 2008 were analyzed. The association of CRC overall survival with age, gender, tumor locations, time, histopathology types, pathology grades, no. of examined lymph nodes, the T stage, and the N stage was analyzed. The assessment of the influence of prognostic factors on patient survival was performed using Cox's proportional hazard regression models. RESULTS: From 1960 to 2008, the studied CRC patients included 2625 (57.6%) and 1933 (42.4%) males and females, respectively. These included 1896 (41.6%) colon cancers, and 2662 (58.4%) rectum cancers. The 5-year survival rate was 49%, 58%, 58%, 70%, and 77% for the time duration of 1960s, 1970s, 1980s, 1990s and 2000s, respectively. An increased 5-year survival rate was observed in the colon cancer and rectum cancer patients. Patients older than 60 years of age were more likely to develop colonic cancer (sigmoid) than rectum cancer (49.2% vs. 39.9%). The Cox regression model showed that only rectum cancer survival was related to time duration. CONCLUSION: The overall survival and 5-year survival rates showed an increase from the 1960s to 2000s. There is a trend of rightward shift of tumor location in CRC patients.

[Expression of molecular markers detected by immunohistochemistry and risk of lymph node metastasis in stage T1 and T2 colorecrectal cancers].

OBJECTIVE: To study the molecular risk factors of lymph node metastasis in stage T1 and T2 colorectal cancers by tissue microarray and immunohistochemistry techniques. METHODS: Two hundred and three patients with stage T1 and T2 colorectal carcinoma who underwent radical surgery from 1999 to 2010 in our department were included in this study. Their clinicopathological data were retrospectively analyzed. Expression of the following 14 molecular markers were selected and assayed by tissue microarray and immunohistochemistry: VEGFR-3, HER2, CD44v6, CXCR4, TIMP-1, EGFR, IGF-1R, IGF-2, IGFBP-1, ECAD, MMP-9, RKIP, CD133, MSI. Chi-squared test and logistic regression were used to evaluate the variables as potential risk factors for lymph node metastasis. RESULTS: The positive expression rates of biomarkers were as following: VEGFR-3 (44.3%), EGFR (30.5%), HER-2 (28.1%), IGF-1R (63.5%), IGF-2 (44.8%), IGFBP-1 (70.9%), ECAD (45.8%), CD44v6 (51.2%), MMP-9 (44.3%), TIMP-1 (41.4%), RKIP (45.3%), CXCR4 (40.9%), and CD133 (49.8%). The positive rate of MSI expression was 22.2%. Both univariate and multivariate analyses showed that VEGFR-3, HER-2, and TIMP-1 were significant predictors of lymph node metastasis. Univariate analysis showed that CD44v6 and CXCR4 were significant significant predictors of lymph node metastasis. CONCLUSIONS: VEGFR-3, HER2 and TIMP-1 are independent factors for lymph node metastasis in stage T1 and T2 colorectal cancers.

Ex vivo localization and immunohistochemical detection of sentinel lymph node micrometastasis in patients with colorectal cancer can upgrade tumor staging.

BACKGROUND: It is not clear if sentinel lymph node (SLN) mapping can improve outcomes in patients with colorectal cancers. The purpose of this study was to determine the prognostic values of ex vivo sentinel lymph node (SLN) mapping and immunohistochemical (IHC) detection of SLN micrometastasis in colorectal cancers. METHODS: Colorectal cancer specimens were obtained during radical resections and the SLN was identified by injecting a 1% isosulfan blue solution submucosally and circumferentially around the tumor within 30 min after surgery. The first node to stain blue was defined as the SLN. SLNs negative by hematoxylin and eosin (HE) staining were further examined for micrometastasis using cytokeratin IHC. RESULTS: A total of 54 patients between 25 and 82 years of age were enrolled, including 32 males and 22 females. More than 70% of patients were T3 or above, about 86% of patients were stage II or III, and approximately 90% of patients had lesions grade II or above. Sentinel lymph nodes were detected in all 54 patients. There were 32 patients in whom no lymph node micrometastasis were detected by HE staining and 22 patients with positive lymph nodes micrometastasis detected by HE staining in non-SLNs. In contrast only 7 SLNs stained positive with HE. Using HE examination as the standard, the sensitivity, non-detection rate, and accuracy rate of SLN micrometastasis detection were 31.8% (7/22), 68.2% (15/22), and 72.2%, respectively. Micrometastasis were identified by ICH in 4 of the 32 patients with HE-negative stained lymph nodes, resulting in an upstaging rate 12.5% (4/32). The 4 patients who were upstaged consisted of 2 stage I patients and 2 stage II patients who were upstaged to stage III. Those without lymph node metastasis by HE staining who were upstaged by IHC detection of micrometastasis had a significantly poorer disease-free survival (p = 0.001) and overall survival (p = 0.004). CONCLUSION: Ex vivo localization and immunohistochemical detection of sentinel lymph node micrometastasis in patients with colorectal cancer can upgrade tumor staging, and may become a factor affecting prognosis and guiding treatment.

Using p53-immunostained large specimens to determine the distal intramural spread margin of rectal cancer.

AIM: To determine the distal intramural spread (DIS) margin of rectal cancer. METHODS: Sixty-one p53-positive specimens of rectal cancer were used. After conventional hematoxylin and eosin (H&E) staining, the DIS margin of rectal cancer in large specimens was examined by immunohistochemistry. The patients were divided into A, B, C, and D groups. After a long-term follow-up, the survival curves of the four groups were estimated using the life table. RESULTS: Fifty-one of the sixty-one cases (83.6%) had DIS. The extent of DIS ranged 0.11-3.5 cm; meanwhile the mean of DIS measured by H&E staining was 0.13 cm. The significant difference was found between the means (t=5.622, P<0.0001). Only 1 of 51 patients had DIS greater than 3 cm. The DIS was less than 1.0 cm in most rectal cancer patients. The long-term results indicated that the survival rate of the patients whose DIS was greater than 1.0 cm was lower than that of the patients whose DIS was less than 0.5 cm. CONCLUSION: Rectal cancer patients with DIS greater than 1.0 cm have poor prognosis.

[Mapping the sentinel lymph node ex vivo and finding the micrometastasis by CK-immunostaining in carcinoma of the colon and rectum].

OBJECTIVE: To evaluate the feasibility and utility of an ex vivo sentinel lymph node (SLN) identification and ultrastaging for colorectal cancer (CRC). METHODS: CRC patients undergoing resection of a primary colorectal cancer were considered for inclusion. Following resection, SLN identification was performed. The SLN was dissected from the mesentery and submitted separately for pathologic analysis. All lymph nodes were stained with HE. Blue lymph nodes, when negative by routine HE staining, were further analyzed. RESULTS: A total of 62 tumors from 60 patients with colorectal cancer were studied. 95.2% (59/62) specimens was successfully identified. In these 59 specimens, a total of 1114 (18.9 per specimens) lymph nodes were examined; of these, 157 (14.9%) were designated as SLNs. The number of blue-stained lymph nodes removed ranged from 1 to 9, with a mean of 2.7 blue nodes identified. The sensitivity of a blue-stained lymph node identifying metastatic disease was 39.1%. The false-negative was 23.7%. In 4 specimens micrometastases were detected only by immunohistochemistry with cytokeratin. CONCLUSIONS: Ex vivo sentinel lymph nodes mapping in colorectal cancer is feasible and can identify the SLNs with a very high success rate. Ex vivo SLN mapping improves pathologic staging of patients with CRC. The SLN evaluation should not replace attempts to harvest large number of nodes for standard processing. SLN mapping can help improving the number of nodes for pathological examination.

[Clinical significance of P53-immunohistochemistry in large slice in evaluating distal intramural spread extent in rectal cancer].

BACKGROUND & OBJECTIVE: The optimal distal molecular clearance margin of rectal cancer hasn't been confirmed. This study was designed to explore the molecular margin of distal intramural spread (DIS)in rectal cancer, and its prognostic value, and to further clarify the required distal margin of radical surgery for rectal cancer. METHODS: Sixty-one P53 positive specimens,resected from patients with rectal cancer from Aug.1996 to Oct. 1997, were collected. Microscopic DIS was examined by P53-immunohistochemistry (P53-IHC),comparing with conventional hematoxylineosin (HE)staining in consecutive large slice. Tissue shrinkage ratio,comparing the distal clearance margin measured in fresh specimens to that measured in large slice after fixed in each case,was used to convert macroscopically measured extent of distal spread to its actual extent. After long-term follow-up, the survival curves of 4 DIS groups were estimated by Life-table method. RESULTS: With P53-IHC,DIS was observed in 50 cases (82.0%), DIS extents were 0.11-3.50 cm with the mean of 0.59 cm, DIS extent of > 3.00 cm was detected in 1 case only. Meanwhile,DIS was observed in 29 cases (47.5%)by HE staining, DIS extents were 0.10-1.39 cm with the mean of 0.13 cm. There was significant difference between the 2 means (P< 0.0001). The long-term result indicated that the survival rate of DIS extent of >1.00 cm group was lower than those of non-DIS group,and DIS extent of < 0.50 cm group (P< 0.05). CONCLUSIONS: DIS was more exactly detected by P53-IHC than by HE. Most of DIS extents were less than 1 cm in rectal cancer. For over 95% cases, 3 cm distal to the rectal cancers was relatively safe in radical operations. The poor prognosis can be predicted in cases with DIS extent of >1 cm.

[Comparing the effect of adjuvant chemotherapy by portal vein infusion with intraluminal chemotherapy for colorectal cancer].

OBJECTIVE: To compare the effect of 5-fluorouracil (5-FU) portal vein infusion (PVI) for 7 days after radical resection, with intraluminal chemotherapy during operation for eliminating liver metastasis and elevating long-term prognosis in colorectal cancer. METHODS: 162 colorectal cancer patients with radical resection were divided into portal vein chemotherapy group (group A, 82 cases) and intraluminal chemotherapy group (group B, 80 cases) randomly. In group A, 5-fluorouracil were infused with 1g per day constantly for 7 days after operation through portal vein catheters, which placed into greater omental vein and fixed on the abdominal wall. In group B, intraluminal chemotherapy was given and 5-fluorouracil 0.5 g was injected into the greater omental vein during operation. RESULTS: The short-term complications and long-term effect in the two groups were compared by statistical software SPSS 8.0. Group A had more operative complications, and no statistical differences was found in hospital time and survival rate of the two groups. The 5-year survival rate is 76.7% (group A: 74.3%, group B: 79.2%), and the liver metastasis rate is 19.8%. There is no significant difference between the two group-survival curves. Multiple variable analysis suggested that Dukes' stage was the prognosis factor (P < 0.05). CONCLUSIONS: The present study demonstrated that the two chemotherapy methods play an important role in preventing liver metastasis and improving the survival rate, and the intraluminal chemotherapy would be easier and simpler. The result should be further improved by using combined chemotherapy.

[An experimental study of inhibiting effect of decoy oligodeoxynucleotides on the gene expression of collagen in NIH3T3 cell].

OBJECTIVE: To investigate the effect of activator protein-1 (AP-1) decoy-oligodeoxynucleotides (Decoy-ODNs) on the expression of fibroblast alpha2 type I collagen, so as to explore the gene therapy of pathologic scar. METHODS: Decoy-ODNs targeting AP-1 were designed and synthesized. NIH3T3 cells were transfected by cationic liposomes. The distribution of Decoy-ODNs in the cells was investigated. The inhibiting effects of Decoy-ODNs on AP-1 were determined by electrophoretic mobility shift assay (EMSA). And the effects of Decoy-ODNs on the collagen synthesis in the cells were analyzed by RT-PCR. RESULTS: AP-1 Decoy-ODNs could competitively inhibit the AP-1 in vitro activity. Cationic liposomes could play roles by effectively transfecting Decoy-ODNs into the plasma and nucleus. The mRNA expression of fibroblast alpha2 type I collagen decreased evidently after 24 hours of Decoy-ODNs action. CONCLUSION: Decoy-ODNs could inhibit the mRNA expression of fibroblast alpha2 type I collagen by antagonizing AP-1.

[Construction,identification and amplification of a yeast two-hybrid random cycle peptide library].

AIM: To construct a cycle peptide library composed of 16 random amino acids with yeast two-hybrid system. METHODS: Random oligonucleotides encoding 16-mer peptides were designed and synthesized artificially, and then were amplified by PCR. The amplified products were digested with BamH I and EcoR I and cloned into yeast expression plasmid pGADT(7) GH to construct the cycle library plasmids pGADT(7) GH-RP Then the number of different recombinants and the randomness of the library were tested, and the cycle peptide library plasmids were amplified, extracted and purified. RESULTS: A random cycle peptide library with 1.28 x10(7) different recombinant clones was obtained. No significant difference was found between amino acid distribution in the cycle peptide library and the expected frequency. CONCLUSION: The random cycle peptide library has been successfully constructed. And a lot of cycle peptide library plasmids with high purity were obtained.