During 3 years of follow-up, 2 patients whose peripheral blood had carcinoembryonic antigen and CD44 variant mRNA also had distant metastases (lung or spleen).
Recently expression of some alternatively-spliced variants of CD44 transcripts (CD44v) has been suggested to play a potential role in tumor metastasis and the detection of CD44v containing exon 6 to 11 may be helpful for the diagnosis of cancers.
Since the CD44 variant 6(v6) molecule has been noted as a marker for tumor metastasis and prognosis in several tumors, we examined whether or not v6 is a useful marker for evaluating the prognosis of pancreatic cancer patients.
The relation between expression of several splicing variants of the CD 44 glycoprotein by tumor cells and the increased risk of metastases was discussed recently.
Expression of none of the CD44 variant epitopes was found to be positively correlated with tumour progression or with colorectal tumour metastasis to the liver, results which are inconsistent with a role for CD44 variants as indicators of colonic cancer progression.
In human colorectal neoplasia CD44 variant proteins, including homologues of those which confer metastatic ability to rat tumors, were found on all invasive carcinomas and carcinoma metastases.
In animal models, isoforms of CD44 (CD44v) containing sequences encoded by one or several of ten different exons (v1-v10) contribute to tumour metastasis.
To investigate if human tumours display altered CD44 expression we performed reverse transcriptase a polymerase chain reaction (PCR) analysis of CD44 in 49 specimens from normal colonic mucosa, primary colon and rectal tumours, normal liver, and metastases of 20 patients.
In 4T1-luc metastatic breast cancer model in mice, Sap-EGFR/CD44-NGs exhibited significant inhibition of tumor metastasis to lung at a small dose of 3.33 nmol Sap equiv./kg.
Recently, it was noted that CD44 participates in a wide variety of cell-cell or cell-matrix interactions including tumor metastasis and the altered expression of CD44 splice variants is helpful in the diagnosis of colon and breast cancer.
In addition, 2-D DIGE and HPLC/MS-MS of HER2(+)/CD44(+)/CD24(-/low) versus HER2(-)/CD44(+)/CD24(-/low) BCSCs reported a unique HER2-associated protein profile including effectors involved in tumor metastasis, apoptosis, mitochondrial function, and DNA repair.
In all normal brain and tumor samples, with the exception ofmetastases from colon carcinoma, PCR analysis demonstrated one prominent product that corresponded to the CD44H hematopoietic form of CD44.
To examine whether renal cell carcinoma displays altered CD44 expression we performed reverse transcription-polymerase chain reaction (RT-PCR) analysis of CD44 in 38 specimens from renal cancer, normal kidney and metastases of 19 patients and 6 renal cancer cell lines.
Furthermore, deguelin-treated tumors showed decreased the tumor metastasis related genes such as CD44, MMP2 and MMP9 at protein and mRNA levels and the content of CEA, SCC, NSE, CYFAR21-1.