Human Ly-6 antigen E48 (Ly-6D) regulates important interaction parameters between endothelial cells and head-and-neck squamous carcinoma cells

Selectin ligands are crucial components in the interaction between endothelial cells and extravasating cancer cells and, thus, play an important role in metastasis formation. Head-and-neck squamous cell carcinoma (HNSCC) variants expressing high levels of E48, a human Ly-6 protein (E48(hi)), expressed higher levels of the fucose-generating FX enzyme and of the fucosylated E-selectin ligand sLe(a) than cells expressing low levels of E48 (E48(lo)). Signaling through E48 upregulated expression levels of these molecules in HNSCC. In this work, we provide further evidence supporting the E48-FX-sLe(a) link by showing that FX antisense oligonucleotides reduced sLe(a) expression levels in HNSCC. We also show that E48 may be causally involved in regulating expression levels in HNSCC of 2 additional enzymes involved in the biosynthesis of sLe(a), namely, ST-30 and FucTIII. Also, selectin-mediated adhesion of E48(hi) variants to activated HUVECs was significantly higher than that of E48(lo) variants. Transfection experiments utilizing sense or antisense E48 cDNA indicated that E48 may be causally involved in this adhesion. Chemokines are involved in the extravasation process of tumor cells. The release of chemoattractants from HNSCC variants differing in E48 expression was therefore analyzed. HNSCC did not release any chemoattractants but induced the release of such factors from HUVECs. Supernatants from E48(hi) variants were significantly more efficient than E48(lo) cells at inducing the release of chemoattractants from HUVECs. Transfection experiments indicated that E48 may be causally involved in the induction of chemoattractant release from HUVECs. Angiogenesis is an important manifestation of cancer-endothelium interactions. We therefore assayed for the presence of angiogenic factors in culture supernatants of HNSCC. Supernatants from E48(lo) variants contained significantly higher amounts of PDGF than E48(hi) cells. Transfection experiments indicated that E48 may be causally involved. Taken together, our results suggest that E48 controls important interaction parameters between HNSCC and endothelial cells.     

Immunomagnetic detection of micrometastatic cells in bone marrow of colorectal cancer patients.

Detection of micrometastatic cells in bone marrow (BM) may potentially be of prognostic value in colorectal cancer (CRC). In the present study, we have evaluated our immunomagnetic detection method in model experiments and on BM samples from CRC patients. In repeated experiments, 11 of 12 CRC cell lines consistently bound MOC31 antibody-coated magnetic particles with an average of 98% of the cells being rosetted with the beads. When different numbers of CRC cells (20, 100, 200, and 1000) were admixed to 1 x 10(7) mononuclear cells (MNCs) from BM, a mean of 77% of the cancer cells was recovered. In BM samples obtained from CRC patients at primary surgery, rosetted tumor cells were detected in 46 of 275 samples (17%) upon screening of 2 x 10(7) MNCs/sample. The fractions positive were: 10% (5 of 49) in Dukes' A; 17% (20 of 115) in Dukes' B; 23% (18 of 78) in Dukes' C; and 9% (3 of 33) in Dukes' D. Of 206 control samples, three (1.5%) contained cells in BM that formed rosettes with the MOC31 beads. In positive samples, a median of eight tumor cells (range, 2-120) were identified per 20-microl examined fraction, representing about one-tenth of the total sample. The results demonstrate the feasibility of using the immunomagnetic method for detection of micrometastatic CRC cells. Furthermore, that screening of 2 x 10(7) MNCs in a BM sample can be completed in <3 h makes the method an attractive alternative to other techniques.     

Determination of oestrogen responsiveness of breast cancer by competitive reverse transcription-polymerase chain reaction.

Competitive polymerase chain reaction assays have been developed for the quantitation of oestrogen receptor mRNA and two oestrogen-regulated mRNAs (progesterone receptor and pNR-2/pS2) in breast cancer cells. These assays are more sensitive than traditional hybridisation techniques, do not require the use of radioisotopes, measure absolute amounts of messenger RNAs and can be used to measure the expression of mRNAs in small numbers of tumour cells obtained by fine-needle aspiration (FNA). These assays should prove useful for predicting the hormone responsiveness of breast cancer from tumour cells obtained by FNA at diagnosis and could be particularly useful in the management of elderly/frail patients who receive primary tamoxifen, or in other patients for whom tumour tissue for standard biochemical measurements is not available.     

逆转录聚合酶链反应检测结直肠癌淋巴结微转移的临床意义

背景与目的:结直肠癌淋巴结微转移灶是否有预测预后价值目前尚有争议,本文对结直肠癌患者淋巴结微转移情况进行逆转录聚合酶链反应(RT-PCR)检测,研究微转移对临床分期和预后的影响。方法:用RT-PCR技术检测56例结直肠癌患者肠旁及系膜淋巴结中细胞角质蛋白CK20mRNA,揭示微转移灶的存在,并与常规病理苏木精伊红(HE)染色和免疫组化染色结果进行比较;分析HE染色和RT-PCR检测结果对判定临床病理分期和统计生存率的影响。结果:共检测432个淋巴结,HE染色、免疫组化染色和RT-PCR法淋巴结转移检出率分别为57.2%、62.3%和73.1%。HE染色和免疫组化的检出率无显著性差异(P>0.05),而HE染色和RT-PCR法检测结果有显著性差异(P<0.05)。56例患者中,按HE染色结果确定的PN0、PN1和PN2期,其5年无复发转移生存率分别为80%、60%和50%;通过RT-PCR技术检测,升级后的PN0、PN1和PN2期5年无复发转移生存率分别为100%、61.9%和55.6%,两种方法分析的结果有显著性差异(P<0.05)。结论:HE染色未确切指出淋巴结微转移癌;RT-PCR法检测CK20mRNA可以推断淋巴结微转移癌的存在,从而有助于确定结直肠癌临床分期和预测预后。     

DETECTION OF MICROMETASTASES OF LUNG CANCER BY USING LUNX mRNA SPECIFIC REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION

Recent years, RT-PCR was widely used to detect micrometastases of various neoplasms. The molecular targets for micrometastases detection were either tumor related or tissue-specific. For example, PSA was used to detect micrometastasis of prostate cancer, tyrosinase was a marker of melanoma[1, 2], while cytokeratin (CKs) and MUC1 were epithelial tissue-specific markers for cancers originate from epithelia[3, 4]. In the detection of micro-metastasis for lung cancer, no specific target was…     

Prognostic relevance of cathepsin D detection in micrometastatic cells in the bone marrow of patients with primary breast cancer

Patients with an elevated level of cathepsin D in breast cancer tissue have an adverse prognosis. This study evaluated the prognostic relevance of cathepsin D detection in disseminated tumour cells in bone marrow. Bone marrow was sampled intraoperatively from both anterior iliac crests in 290 patients with primary breast cancer. Interphase cells were enhanced and stained immunocytologically with two antibodies: BM2, which detects tumour-associated glycoprotein TAG 12, which is typically expressed by almost all breast cancer cells, and the anti-cathepsin D antibody. 67 of 149 BM2-positive women (45%) developed metastatic disease (median follow-up time: 69 months). Of these, 15 were cathepsin D-positive (22%). Patients with cathepsin D-positive cells in bone marrow (n = 26; 9%) had a significantly shorter metastasis-free interval (38 months) compared with women who were cathepsin D-negative (64.5 months). The worst prognosis was seen in patients positive for both markers (30.5 months), followed by those who were cathepsin D-negative and BM2-positive (48 months). The detection of cathepsin D on disseminated tumour cells characterises a subgroup of patients with a poorer prognosis who should undergo more aggressive adjuvant systemic therapy.     

Clinical significance of occult metastatic cells in bone marrow of breast cancer patients

The early and clinically occult spread of viable tumor cells to the organism is increasingly considered a hallmark in cancer progression, as emerging data suggest that these cells are precursors of subsequent distant relapse. Using monoclonal antibodies to epithelial cytokeratins or tumor-associated cell membrane glycoproteins, individual carcinoma cells can be detected on cytologic bone marrow preparations at frequencies of 10(-5) to 10(-6). Prospective clinical studies have shown that the presence of these immunostained cells in bone marrow, as a frequent site of overt metastases, is prognostically relevant with regard to relapse-free and overall survival. This screening approach may be, therefore, used to improve tumor staging and guide the stratification of patients for adjuvant therapy in clinical trials. Another promising application is monitoring the response of micrometastatic cells to adjuvant therapies, which, at present, can only be assessed retrospectively after an extended period of clinical follow-up. The present review summarizes the current data on the clinical significance of occult metastatic breast cancer cells in bone marrow.