The Analysis Of The Relationship Between CD44V6 Expression And Colorectal Carcinoma Metastasis

Metastasis and invasion are not only the basic biological features of malignant tumor but also the main cause of death. In recent years, the incidence of colorectal carcinoma has been increasing, but the postoperative five - year survival rate remains unimproved about 50%. Early diagnosis enables the timely surgical therapy for a better outcome. Numerous studies have indicated that the metastasis of malignant tumors depends on the tumor cell's interaction with extracellular metrix and other cells by which the adhension molecules on the surface of tumor cells play an important role.As the adhension molecule and the main transmembrane hyalur-onate receptor, CD44 family is the determinative factor of the tumor is invasion and metastasis. It is well elucidated that the expression of CD44 Splice Variants (CD44V) , particularly CD44V6, is closely related to tumors growth, infiltration, metastasis and prognosis.Our experiment is to unravel the relationship between CD44V6 expression and colorectal carcinoma metastasis. Our aim is to uncover the role of CD44V6 in the carcinogenesis. Metastasis and prognosis of colorectal carcinoma which may serve as the theoretical basis and effective method for early diagnosis, prognosis and effective therapy.MaterialAll the 112 cases were sampled from the operation room and ascertained by pathological examination. Their clinical and pathological data were complete. The mucosa 10cm away from the tumor was sampled respectively for control. Among the patients whose average age is 52. 8 years old (32 -80 years old) , 64 cases were male and 48 female. All samples were classified nistologically as poorly, moderately, well differentiated and mucous carcinoma, and were grouped as protruding, ulcer, colloid and infiltrative types according to the macroscopic appearance. Dukes criterion was adopted for clinical staging. None of the patients had adjuvant treatment before operation.MethodBoth the tumor tissue and control group were subject to immuno-chemistry examination by SP staining method. Semi - qualitive examination was done by microscopic observation and the evaluation such as "negative" ( - ) , " positive" ( + ) and " strong positive" ( ++ ) was given. The patients were grouped according to sex, age, macroscopic manifestation, pathological type, histological type, sex, metastasis of lymph node and Dukes staging. x2 testing was used for statistics analysis.Result" CD44V6 positive" referred to yeallow, brown and reddishbrown expression positioned mainly on the cell membrane with the cy-tosplasm stained to lesser extent. Among 112 cases, 98 were positively stained and the positive rate was 87. 5% (98/112). For the control group,39 cases were positively stained and the positive rate was 34. 8 (39/112). There was significant difference between carcinoma sample group and the control (P<0.01). 41 cases of 42 patients with lymph node metastasis were obviously stained (the positive rate was 97.6% (41/42) ). There was significant difference (P <0.05). The positive expression of Dukes C and D stages was obviously higher than Dukes A and B stages and there was significant difference ( P < 0. 05). However, 57 cases of 70 patients without lymph node metastasis were stained (the positive rate was 81. 4% (51/70)). All the patients with distant metastasis showed positive expression ( positive rate 100% (11/11)) and there was significant difference compared with those without distant metastasis (P<0.01). It was worthy to note that patients with metastasis had the strong positive expression of CD44V6. But, CD44V6 expression was out of relationship with age, sex, macroscopic appearance, pathological type, histological type and size (P >0.05).DiscussionOur research work proved that CD44V6 expressed to various extent on the colorectal tumor cell membrane, but no expression presented on the normal intestinal tissue and adjacent region of tumors. This result agreed with exotic report. It indicated that CD44 was possibly associated with the genesis and development of colo...