食管源性转移瘤(癌)的现状回顾与归纳

食管源性转移瘤(癌)是指食管原发性恶性肿瘤经血道转移到人体各部位的组织或器官。发生移位状态的转移瘤(癌)是临床治疗的难题和预后不良的主要原因,也是目前肿瘤研究中的重要领域和热点。该文收集了国内的相关资料,对其发病现状、发生机制、影响因素、早期诊断及治疗原则进行回顾与归纳。

Hilar Cholangiocarcinoma with Synchronous Metastases to Breast and Skeletal Muscle: A Case Report and Literature Review

Hilar cholangiocarcinoma has been reputed as a slow growth tumor in the past. Skeletal muscle is one of the most unusual sites of metastasis from any malignancy. We report herein a case of hilar cholangiocarcinoma with synchronous metastases to skeletal muscle and breast, and review the literature. The patient was a 48-year-old woman who presented with jaundice and weight loss. An inoperable hilar cholangiocarcinoma was diagnosed. She was treated with a combination of endoscopic plastic stent biloiary drainage and three-dimensional conformal radiotherapy （3DCRT）. Good response was achieved. Ten months later, she exhibited with a painful metastatic mass in the muscle rectus femoris of left thigh and a painless mass in the left breast. She underwent operation to relieve the pain, but died from liver failure after 8 months. The literature only offers isolated cases of cholangiocarcinoma with distant metastases, of which the common sites were cervical lymph node, bone, and portal venous system. Most patients were presented with multiple metastases with extensive local disease.

Expression of COX-2 in Different Subtypes of Gastric Intestinal Metaplasia and Gastric Carcinoma by Tissue Microarray

Objective: To study the expression of cyclooxygenase-2 (COX-2) protein in different subtypes of intestinal metaplasia (IM) and gastric carcinoma, evaluate the possibility of COX-2 forecasting the risk of malignant potential of IM, and the relationship between COX-2 expression and gastric carcinogenesis. Methods: Forty cases of chronic atrophic gastritis (CAG) with IM, 40 cases of gastric carcinoma and corresponding paracancerous tissues were selected to construct a tissue microarray. High iron diamine/alcian blue (HID/AB) staining and Hematoxylin and Eosin (HE) staining was used to classify IM and gastric carcinoma, and the expression of COX-2 protein detected in different subtypes of IM and gastric cancer by using immunohistochemistry. Results: The positive expression rate of COX-2 was 45.65%, 59.38% and 77.27% in IM foci in CAG, IM foci in paracancerous tissues, and intestinal-type gastric carcinoma, respectively, significantly higher than in diffuse-type gastric cancer (16.67%)(P<0.05, 0.005 and 0.005, respectively), and the expression intensity of COX-2 protein showed a increased tendency gradually in the sequence of IM foci in CAG→IM foci in paracancerous tissues→intestinal-type gastric carcinoma (P<0.005). The positive expression rate of COX-2 protein in type Ⅲ IM was significantly higher than in type Ⅰ and type Ⅱ IM (P<0.005 and 0.05, respectively), and the expression intensity also showed a increased tendency gradually from type Ⅰ to type Ⅲ IM (P<0.005). Conclusion: The expression level of COX-2 was increased gradually along with the increase of the risk of malignancy of IM, and its expression level may be a useful index to forecast the risk of malignant potential of IM. COX-2 expression was associated with intestinal-type gastric carcinoma, but it might also have some role in the carcinogenesis of diffuse-type gastric carcinoma.

Comparative Study of CT Images of Cerebral Metastasis from Pulmonary Squamous Cell Carcinoma and Adenocarcinoma

Objective: To explore the di?erence of CT images of metastatic tumors to the brain of lung squamous cell cancer and lung glandular cancer. Methods: Forty-?ve cases of lung squamous cell cancer and 59 cases of lung glandular cancer have gone through pathological con?rmation and all the 104 cases have been put under enhanced scanning on the basis of ?at scanning. The shape and density of the metastatic tumors, encephaledema around the tumors, and the reinforcement change after the enhancement were analyzed. Results: The CT scanning images of all the cases showed that, under ?at scanning, the density of the metastatic tumors to the brain of lung squamous cell cancer was over the slightly-high level and by no means even. Again, under ?at scanning, some 10 cases of metastatic tumors to the brain of lung glandular cancer showed a slightly-high density and some 49 other cases a low density and sack-like low density. Forty-?ve cases of metastatic tumors to the brain of lung squamous cell cancer were with hydroncus while some 30 cases of that of lung glandular cancer were in the same condition. Most of the two types of metastatic tumors, amounting to 97 cases, took place in supratentorial manner, and only 7 cases took place in subtentorial manner. Conclusion: The CT images of metastatic tumors to the brain of lung squamous cell cancer and lung glandular cancer are obviously di?erent from each other. As for the lung squamous cell cancer, the ?at scanning density of the tumor is over the slightly-high level with unevenness. There is relatively obvious reinforcement and obvious hydroncus. As for the lung glandular cancer, the metastatic tumor to the brain shows a low density and sack-like low density under ?at scanning. There is no obvious reinforcement and relatively slight hydroncus.

An Analysis of Prospective Outcome of Re-resection for Recurrent Live Cancer and Extrahepatic Metastases,a Follow-up of 267\Cass

Objective To evaluate the prospective outcome and summarize experience in re-resection for recurrent liver cancer and extrahepatic metastases. Methods The clinical data of 267 patients with recurrent primary liver cancer (PLC) after re-resection from January 1960 to July 2000 were retrospectively analyzed. Re-hepatectomy was performed on 205 cases, resection of extrahepatic metastases on 51 cases and combined resection of recurrent liver cancer and extrahepatic metastases on 11 cases. The clinico-pathologic features, operation type and survival were compared. Results The types of liver re-resection included left lateral lobectomy in 11.2% of patients, hemihepatetomy and extended hemi-hepatectomy in 4.4%, local radical resection in 68.3%, other subsegmentectomy in 17.1%. The peak recurrence rate (64.4%) occurred at 1–2 years. The overall 1-, 3, 5- and 10-year survival rates after second resection were 81.0%, 40.3%, 19.4% and 9.0% respectively, while they were 77.5%, 29.8%, 13.2% and 6.61% respectively after the third resection. The median survival time was 44 months. The re-resection with extrahepatic metastases also provided the possibility of longer survival. Conclusion The results suggest that subsegmentectomy and local excision is appropriate for the hepatic repeat resection. The peak recurrence may be correlated with portal thrombus and operative factor. The re-resection can be indicated not only in intrahepatic recurrent metastases but also in extrahepatic metastases in selected patients. Re-resection has become the treatment of choice for recurrence of PLC, as neither chemotherapy nor other nonsurgical therapies can achieve such favorable results. Key words prospective outcome - re-resection - primary liver cancer - recurrence - extrahepatic metastases

The Relationship between the Expression of p27^(Kip1),p53 and the Infiltration,Metastasis and Prognosis in Gastric Carcinoma

Objective: To study the relationship between the expression of p27Kip1 and p53, and the infiltration, metastasis and prognosis in gastric carcinoma. Methods: The expression of p27Kip1 and p53 at protein level was determined by immunohistochemical assay (two-step method) in 100 cases of gastric carcinoma. Results: Of the 100 cases, the positive rate of p27Kip1 and p53 expressions were 44% and 49%, respectively. In the group of gastric carcinomas with deep infiltration (infiltration group), lymph nodes metastasis group (metastasis group) and death-within-5-years group (death group), the expression of p27Kip1 was statistically lower (_P<0.05). In the metastasis group and death group, the expression of p53 was significantly higher (P<0.05). The results of the monovariate analysis revealed that the 5-year survival rate of the high p27Kip1 expression group was 70.59%, which is higher than those of the low p27Kip1 expression group (54.55%) and the negative experession group (26%). The 5-year survival rate of the high p53 expression group was 19.23%, which was lower than those of the p53 low expression group (43.75%) and the negative group (53.19%). Cox multivariate analysis showed that p27Kip1, like p53, was an independent prognostic index. But p27Klpl protein expression was a stronger independent survival predictor (RR=3.06) than p53 expression (RR=2.33). Conclusion: The low expression of p27Kip1 and the high expression of p53 reflected the more frequent invasion and metastasis, which resulted in the reduced survival of patients. As an independent markers of the gastric carcinoma, the expression of p27Kip1 is more useful than that of p53 in the prognosis prediction of gastric carcinoma.

Effect of Bcl-2 Antisense Oligodeoxynucleotides on Human Lung Carcinoma Transplanted Subcutaneously in Nude Mice

Objective： To investigate the inhibitory effects of the Bcl-2 antisense oligodeoxynucleotides （ASODN） on tumor formation and growth of human lung carcinoma transplanted subcutaneously in nude mice. Methods： Human NCI-H460 cells treated with Bcl-2 ASODN or nonesense oligodeoxynucleotide （NSODN） and untreated NCI-H460 cells were respectively implanted subcutaneously into nude mice. When the diameters of tumor were above 0.5 cm after untreated NCI-H460 cells injection, the mice bearing tumor were randomly divided into three groups： saline control group, Bcl-2 ASODN group, NSODN group. ODN was directly injected into the tumor body for 3 weeks. The weight and volume of subcutaneous tumors were measured, and the morphology of tumor cells was observed. Results： The tumorigenic ability of the treated NCI-H460 cells by Bcl-2 ASODN was reduced. The mean time at which tumor can be detected was prolonged up to 12.6 days （P〈0.01）. The maximum tumor growth inhibitory rate was 87.5%. In therapeutic efficacy, growth of tumor was significantly inhibited in Bcl-2 ASODN group as compared with that in NSODN group, saline-treated group （P〈0.01）. The NSODN control was ineffective. In comparison with NSODN-treated, saline-treated mice, those treated with Bcl-2 ASODN showed a significant decrease in median weight of subcutaneous tumors （P〈0.01）. The growth inhibitory rate was 71.0% in ASODN group. Conclusion： Bcl-2 ASODN could inhibit tumor formation and tumor growth in nude mice.

Peritoneal lavage cytology and carcinoembryonic antigen determination in predicting peritoneal metastasis and prognosis of gastric cancer

AIM: To evaluate the role of peritoneal lavage cytology (PLC) and carcinoembryonic antigen (CEA) determination of peritoneal washes (pCEA) in predicting the peritoneal metastasis and prognosis after curative resection of gastric cancer.METHODS: PLC and radioimmunoassay of CEA were performed in peritoneal washes from 64 patients with gastric cancer and 8 patients with benign diseases.RESULTS: The positive rate of pCEA (40.6%) was significantly higher than that of PLC (23.4%) (P<0.05).The positive rates of PLC and pCEA correlated with the depth of tumor invasion and lymph node metastasis (P<0.05). pCEA was found to have a higher sensitivity and a lower false-positive rate in predicting peritoneal metastasis after curative resection of gastric cancer as compared to PLC. The 1-, 3-, and 5-year survival rates of patients with positive cytologic findings or positive pCEA results were significantly lower than those of patients with negative cytologic findings or negative pCEA results (P<0.05). Multivariate analysis indicated that pCEA was an independent prognostic factor for the survival of patients with gastric cancer.CONCLUSION: Intraoperative pCEA is a more sensitive and reliable predictor of peritoneal metastasis as well as prognosis in patients with gastric cancer as compared to PLC method.

Lymph node micrometastasis and its correlation with MMP-2 expression in gastric carcinoma

AIM： To examine matrix metalloproteinase-2 （MMP-2） expression in gastric cancer tissues and to evaluate its relationship with lymph node micrometastasis. MATERIALS： The authors studied 850 lymph nodes resected from 30 patients with gastric carcinoma who underwent gastrectomy with lymphadenetomy using reverse transcription polymerase chain reaction （RT-PCR） assay in addition to H-E staining. MMP-2 expression of the tumor tissues was detected by immunohistochemical technique （EliVision^TM plus）. RESULTS： MMP-2 expression was positive in 21 （70%） cases and negative in g （30%） cases. No significant correlations were found between MMP-2 expression and other variables such as age, gender, tumor location, tumor diameter, Lauren classification and lymphatic invasion. In contrast, MMP-2 expression correlated significantly with depth of tumor infiltration （P = 0.022）, lymph node metastasis （P = 0.030） and tumor differentiation （P = 0.043）. Lymph node micrometastases were detected in 77 （12.5%） lymph nodes of 14 （46.7%） gastric carcinoma patients. MMP-2 expression was positive in 12 （85.7%） of the 14 patients with lymph node micrometastasis, and in g （56.3%） of the 16 patients without lymph node micrometastasis （P = 0.118）. CONCLUSIONS： Our results demonstrate that MMP-2 expression has significant correlation with tumor invasion, tumor differentiation and lymph node metastases. MMP-2 expression may be an important biological characteristics and significant prognostic parameter of gastric carcinoma. We also conclude that MMP-2 may participate in the development of lymph node micrometastasis of gastric carcinoma. Further investigations are needed to draw a conclusion.

Chest wall metastasis from unknown primary site of hepatocellular carcinoma

Previous reports of a solitary metastatic hepatocellular carcinoma have been rare. Because this tumor has a different treatment modality and prognosis, an accurate differential diagnosis is essential. Here we report a rare case of a solitary chest wall metastasis from unknown primary site of hepatocellular carcinoma. It involves a 51-year-old man who was admitted to our hospital because of a palpable left upper chest wall mass. The mass was resected and pathologic examination confirmed a diagnosis of metastatic hepatocellular carcinoma. Despite our investigation, no evidence was found that indicated the primary origin of the hepatocellular carcinoma. Four months later, the patient was admitted again because of spinal cord compression at the third and fourth thoracic vertebrae. Emergent decompressive laminectomy was performed and microscopic features revealed the same pathology as the initial chest wall mass resected 4 months earlier. After one year, a follow-up abdominal computed tomography （CT） still revealed no evidence of primary hepatocellular carcinoma.

CD44v6 in peripheral blood and bone marrow of patients with gastric cancer as micro-metastasis

AIM： To detect the expression of CD44 correlated with the ability of micro-metastasis in peripheral blood and bone marrow of patients with gastric cancer and to deduce its clinical significance. METHODS： Preoperative peripheral blood and bone marrow specimens from 46 patients with gastric cancer and 6 controls were studied by semi-quantitative RTPCR amplification of CD44v6mRNA. Preoperative and postoperative peripheral blood specimens from 40 patients with gastric cancer and 14 controls were studied by quantitative RT-PCR amplification of CD44v6mRNA in the corresponding period. RESULTS： Semi-quantitative RT-PCR amplification showed that CD44v6mRNA expression of peripheral blood and bone marrow was positive in 39 （84.8%） and 40 （86.9%） of 46 patients with gastric cancer, respectively. In peripheral blood, CD44v6mRNA expression was positive for diffuse type in 30 （93.8%） of 32 patients and for intestinal type in 9 （64.3%） of 14 patients. On the other hand, in bone marrow, CD44v6mRNA expression was positive for diffuse type in 31 （96.9%） of 32 patients and for intestinal type in 10 （71.4%） of 14 patients. There was a significant difference between the diffuse type and intestinal type. Quantitative RTopCR amplification demonstrated that CD44v6mRNA was not expressed in the peripheral blood of controls and CD44v6mRNA expression was positive for preoperative peripheral blood in 40 patients with gastric cancer, the expression levels being from 4.9 × 10^2 to 3.2× 10^5 copies/g RNA. The average expression level of CD44v6mRNA in peripheral blood was 3.9 × 10^10 copies/g RNA. The expression levels of CD44v6mRNA in peripheral blood in gastric cancer patients after curative operation increased from 5.5 × 100 to 7.6 × 10 copies/g RNA （P = 0.00496）. After curative operation, the expression level decreased markedly. CONCLUSION： Semi-quantitative and quantitative RTPCR amplification for CD44v6mRNA is a sensitive and specific method for the detection of micro-metastasis in peripheral blood and bone marrow, which might be used as an indicator of tumor burden and therapeutic effect.

Study on interleukin-18 gene transfer into human breast cancer cells to prevent tumorigenicity

To study the effect of interleukin-18 gene transfection on the tumorigenesis of breast cancer cell line Bacp37,human breast cancer cell line Bcap37 were transfected with Lipofectamine and selected by G418.The biological expression of rhIL-18 was tested by RT-PCR and ELISA method;nude mice were injected with Bcap37 cell with or without the hIL-18 gene.The hIL-18 cDNA was successfully integrated into Bcap37 cell; 126.3±4.5pg hIL-18 secreted by one million transduced cells in 24 hours. Nude mice injected with IL-18 gene engineered Bcap37 cell had no tumor growth.These findings indicated that human breast cancer cells were successfully modified by the gene of IL-18 cytokine;the IL-18 gene engineered Bcap37 cells secreted hIL-18 and lost their tumorigenicity.The Bcap37 cells transduced with IL-18 gene may be used as breast cancer vaccine.

Antithrombin reduces reperfusion-induced hepatic metastasis of colon cancer cells

AIM： To examine whether antithrombin （AT） could prevent hepatic ischemia/reperfusion （I/R）-induced hepatic metastasis by inhibiting tumor necrosis factor （TNF）-α-induced expression of E-selectin in rats. METHODS： Hepatic I/R was induced in rats and mice by clamping the left branches of the portal vein and the hepatic artery. Cancer cells were injected intrasplenically. The number of metastatic nodules was counted on day 7 after I/R. TNF-α and E-selectin mRNA in hepatic tissue, serum fibrinogen degradation products and hepatic tissue levels of 6-keto-PGF1α, a stable metabolite of PGI2, were measured. RESULTS： AT inhibited increases in hepatic metastasis of tumor cells and hepatic tissue mRNA levels of TNF-α and E-selectin in animals subjected to hepatic I/R. Argatroban, a thrombin inhibitor, did not suppress any of these changes. Both AT and argatroban inhibited I/R-induced coagulation abnormalities. I/R-induced increases of hepatic tissue levels of 6-keto-PGF1α were significantly enhanced by AT. Pretreatment with indomethacin completely reversed the effects of AT. Administration of OP-2507, a stable PGI2 analog, showed effects similar to those of AT in this model. Hepatic metastasis in congenital AT-deficient mice subjected to hepatic I/R was significantly increased compared to that observed in wild-type mice. Administration of AT significantly reduced the number of hepatic metastases in congenital AT-deficient mice. CONCLUSION： AT might reduce I/R-induced hepatic metastasis of colon cancer cells by inhibiting TNF-α-induced expression of E-selectin through an increase in the endothelial production of PGI2. These findings also raise the possibility that AT might prevent hepatic metastasis of tumor cells if administered during the resection of liver tumors.

Impact of lymph node micrometastasis in hilar bile duct carcinoma patients

AIM- To immunohistochemicaUy examine micrometastasis and VEGF-C expression in hilar bile duct carcinoma （HBDC） and to evaluate the clinical significance of the results. METHODS： A total of 361 regional lymph nodes from 25 patients with node-negative HBDC were immunostained with an antibody against cytokeratins 8 and 18 （CAM 5.2）, and immunohistochemical staining of VEGF-C was performed in 34 primary resected tumors. RESULTS： Lymph node micrometastasis was detected in 6 （24%） of the 25 patients and 10 （2.8%） of the 361 lymph nodes. Patients with micrometastasis showed significantly poorer survival rates than those without （P= 0.025）. VEGF-C expression was positive in 17 （50%） of 34 HBDC, and significantly correlated with lymph node metastasis （P=0.042） and microscopic venous invasion （P=0.035）. CONCLUSIONS： It is suggested that immunohistochemically detected lymph node micrometastasis has an impact on the outcome of HBDC. VEGF-C expression is highly correlated with lymph node metastasis in HBDC and might therefore be a useful predictor.

K-19 mRNA RT-PCR in detecting micrometastasis in regional lymph nodes of gastric cancer

AIM： To investigate the value and prospect of RT-PCR in detecting micrometastasis in regional lymph nodes of gastric cancer. METHODS： Histopathology was used and K19 mRNA expression was detected by RT-PCR in tumor tissues and lymph nodes from gastric cancer patients undergoing radical resection of gastric carcinoma. RESULTS： K19 mRNA was expressed in all tumor specimens of 30 cases; of the 126 lymph nodes, 26 were histopathologically positive （20.6%）, and 42 positive （33.3%） by RT-PCR. Amplification fragments of 460 and 540 bp were shown in all the tumor tissues and metastatic lymph nodes after K19 and β-actin RT-PCR, while only a 540 bp fragment appeared in the lymph nodes of non-tumor patients. CONCLUSION： K19 mRNA RT-PCR is sensitive and specific in testing micrometastasis in regional lymph nodes of gastric cancer, and it is superior to routine histopathology.

Down-regulation of miR-622 in gastric cancer promotes cellular invasion and tumor metastasis by targeting ING1 gene

AIM:To evaluate the biological and clinical characteristics of miR-622 in gastric cancer. METHODS:We analyzed the expression of miR-622 in 57 pair matched gastric neoplastic and adjacent non-neoplastic tissues by quantitative real-time polymerase chain reaction. Functional analysis of miR-622 expression was assessed in vitro in gastric cancer cell lines with miR-622 precursor and inhibitor. The roles of miR-622 in tumorigenesis and tumor metastasis were analyzed using a stable miR-622 expression plasmid in nude mice. A luciferase reporter assay was used to assess the effect of miR-622 on inhibitor of growth family,member 1 (ING1) expression. RESULTS:Expression of miR-622 was down-regulated in gastric cancer. MiR-622 was found involved in differentia-tion and lymphatic metastasis in human gastric cancer. Ectopic expression of miR-622 promoted invasion,tumorigenesis and metastasis of gastric cancer cells both in vitro and in vivo. ING1 is a direct target of miR-622. CONCLUSION:These findings help clarify the molecular mechanisms involved in gastric cancer metastasis and indicate that miR-622 modulation may be a bona fide treatment of gastric cancer.

OB glue paste technique for establishing nude mouse human gastric cancer orthotopic transplantation models

AIM： To establish nude mouse human gastric cancer orthotopic transplantation models using OB glue paste technique. METHODS： Using OB glue paste technique, orthtopic transplantation models were established by implanting SGC-7901 and NKN-45 human gastric cancer cell strains into the gastric wall of nude mice. Biological features, growth of the implanted tumors, the success rate of transplantation and the rate of auto-metastasis of the two models were observed. RESULTS： The success rates of orthotopic transplanration of the two models were 94.20% and 96%. The rates of hepatic metastasis, pulmonary metastasis, peritoneal metastasis, lymphocytic metastasis and splenic metastasis were 42.13% and 94.20%, 48.43% and 57.97%, 30.83% and 36.96%, 67.30% and 84.06%, and 59.75% and 10.53%, respectively. The occurrence of ascites was 47.80% and 36.96%. CONCLUSION： OB glue paste technique is easy to follow. The biological behaviors of the nude mouse human gastric cancer orthotopic transplantation models established with this technique are similar to the natural processes of growth and metastasis of human gastric cancer, and, therefore, can be used as an ideal model for experimental research of proliferative metastasis of tumors.

Correlation between CK18 gene and gastric carcinoma micro metastasis

AIM: To explore the biological behavior of gastric carcinoma micrometastasis (MM) with a marker of cytokeratin 18 (CK18) and to evaluate the clinical stage of gastric carcinoma and its prognosis. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used to examine the expression of CK18 mRNA in 298 lymph nodes from 35 patients with gastric carcinoma and 20 lymph nodes from 10 patients with chronic peptic ulcer and gastric perforation diagnosed by pathological examination and surgery.CK18 mRNA expression of peripheral blood from 54 patients with gastric carcinoma and 10 healthy people were also examined.RESULTS: Expression of CK18 mRNA was not found in 10 patients with benign pathological changes.CK18 mRNA expression in gastric carcinoma tissues was strongly positive. In gastric carcinoma patients,pathological examination revealed that 99 of 298 (33.2%)lymph nodes were positive, while RT-PCR showed that 133 of 298 (44.6%) lymph nodes had expression of CK18 mRNA. The difference was significant (P＜0.05).Among the 199 negative lymph nodes identified by pathological examinations, 34 (17.1%) displayed positive expression of CK18 mRNA by RT-PCR. The positive expression of CK18 mRNA was associated with lymph node micrometastasis (LMM) of gastric carcinoma. CK18 mRNA was negatively expressed in all 10 healthycases and positively expressed in 38.9% of 54 blood specimens from gastric carcinoma patients. The positive rate was not correlated with tumor invasion of gastric carcinoma,but was significantly associated with TNM stage, lymph node metastasis (P=0.0290, P＜ 0.05) and tumor differentiation (P= 0.2956, P＜0.05).CONCLUSION: RT-PCR with CK18 mRNA as a molecular marker is highly sensitive and specific in detecting LMM of gastric carcinoma. It can benefit the diagnosis of MM and guide studies on biological behavior, clinical phase,and therapy as well as relapse monitoring.

MUC1 and colorectal cancer pathophysiology considerations

Several lines of evidence point towards a biological role of mucin and particularly MUC1 in colorectal cancer. A positive correlation was described between mucin secretion, proliferation, invasiveness, metastasis and bad prognosis. But, the role of MUC1 in cancer progression is still controversial and somewhat confusing. While Mukherjee and colleagues developed MUC1-specific immune therapy in a CRC model, Lillehoj and coinvestigators showed recently that MUC1 inhibits cell proliferation by a β-catenin-dependent mechanism. In carcinoma cells the polarization of MUC1 is lost and the protein is over expressed at high levels over the entire cell surface. A competitive interaction between MUC1 and E-cadherin, through β-catenin binding, disrupts E-cadherin-mediated cell-cell interactions at sites of MUC1 expression. In addition, the complex of MUC1-β-catenin enters the nucleus and activates T-cell factor/leukocyte enhancing factor 1 transcription factors and activates gene expression. This mechanism may be similar to that just described for DCC and UNC5H, which induced apoptosis when not engaged with their ligand netrin, but mediate signals for proliferation, differentiation or migration when ligand bound.

Mechanism of metastasis by membrane type 1-matrix metalloproteinase in hepatocellular carcinoma

AIM To investigate the precise role of membrane type 1-matrix metalloproteinase （NTI-NNP） in hepatocellular carcinoma （HCC） metastasis. METHODS- Human HCC cells Hep3B with overexpression of MTT-MMP were established by stable transfection, and compared with control cells carrying the empty vector. Cells were examined in vivo for their differences in the metastatic ability of athymic nude mice, and analyzed in vito for their differences in invasion ability by invasion chamber coated with Matrigel, adhesion towards collagen I and migration through culture chamber. Cell proliferation and apoptosis in adherent and suspension status were evaluated by MTr and flow cytometry analysis. RESULTS We found that overexpression of MT1-MMP could increase intrahepatic metastasis in nude mice with orthotopic implantation of HCC cells （incidence of 100% [MT1-MMP transfectants] vs 40% [vector control transfectants], P〈0.05）. NT1-MMP could also enhance cell invasion through Natrigel （107.7 vs 39.3 cells/field, P〈0.001）, adhesion towards matrix （0.30 vs 0.12 absorbance unit at 540 nm, P〈0.001）, cell migration （89.3 vs 39.0 cells/field, P〈0.001）, and cell proliferation （24.3 vs 40.5 h/doubling, P〈0.001）. We also observed that NTI-NNP supported cell survival （71.4% vs 23.9%, P〈0.001） with reduced apoptosis （43.7% vs51.0%, P〈0.05） in an attachment-free environment. CONCLUSION： MT1-MMP overexpression could enhance metastasis. In addition to its active role in matrix degradation during tumor invasion, MT1-MMP enhances tumor cell survival upon challenge of detachment, which is important during metastasis when cells enter the circulation.