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Using reverse transcriptase and the polymerase chain reaction (PCR) to detect fetal RNA in maternal blood samples may be helpful in identifying RhD-positive fetuses. Reverse transcriptase is an enzyme that converts RNA into DNA. Fetal messenger RNA is much more abundant in maternal blood samples than fetal DNA. Researchers used this technique to detect RhD-positive fetuses in 35 RhD-negative pregnant women. This technique identified more RhD-positive fetuses than traditional PCR tests for fetal DNA in maternal blood. Normally, amniocentesis or chorionic villus sampling is used for prenatal diagnosis, but they can harm the fetus.

Background: The production of the cytokine interferon gamma (IFN [Gamma]) by activated peripheral blood mononuclear cells may be reduced in patients with invasive cervical carcinoma. This study was designed to assess the prognostic value of intratumoral IFN [Gamma] messenger RNA (mRNA) levels in such patients. Methods: Biopsy specimens of primary cervical lesions were obtained from 27 patients with invasive squamous cell carcinoma before they received any therapy. Two prognostic groups were considered: 1) a group of 14 patients who had no apparent disease recurrence and who were alive 2 years after diagnosis (good-prognosis group) and 2) a group of 13 patients who had disease recurrence or died during the 2-year follow-up (poor-prognosis group). A competitive reverse transcription-polymerase chain reaction assay was used to measure levels of IFN [Gamma] and [Beta] actin mRNA. The expression of human leukocyte antigen (HLA) class II proteins (which is stimulated by IFN [Gamma]) in tumor cells was studied by immunostaining. Results: Tumor specimens from all 14 patients in the good-prognosis group contained more than [10.sup.3] IFN [Gamma] mRNA copies per 5 x [10.sup.5] [Beta] actin mRNA copies, whereas tumor specimens from only six of the 13 patients in the poor-prognosis group contained this level of IFN [Gamma] mRNA (two-sided P = .006). No clear relationship was observed between levels of IFN [Gamma] mRNA and T-cell or natural killer cell infiltration in tumors; however, a statistically significant association was observed between HLA class II expression on tumor cells and IFN [Gamma] mRNA levels (two-sided P = .01). Conclusions: A subgroup of poor-prognosis cervical carcinoma patients who have low levels of intratumoral IFN [Gamma] mRNA was identified. [J Natl Cancer Inst 1998; 90:287-94]

A simple technique used to evaluate messenger ribonucleic acid (mRNA) patterns called polymerase-chain reaction appears to provide useful information about changing gene expression in the uterine lining during pregnancy. Uterine lining samples taken from 30 pregnant rats on days 12, 16, 20, 21, 22 of pregnancy and one day after delivery were analyzed using polymerase-chain reaction. More than 500 mRNA sequences were identified. Some sequences were expressed more frequently and some less frequently as the pregnancy advanced.

The tax gene of human T-cell lymphotropic virus type I (HTLV-I) may be responsible for the proliferation of T cells that results in adult T-cell leukemia. Blood samples were taken from 194 HTLV-I carriers and classified into four groups depending on whether HTLV-I proviral DNA levels were high, medium, low or undetectable. The polymerase chain reaction detected tax RNA in 3% of the samples with low or undetectable levels but in 40% of the samples with high levels. Blood samples with high proviral DNA levels also had a greater percentage of cells with the interleukin-2 receptor, which can cause cell proliferation.

Leukemia inhibitory factor (LIF) may play a role in early embryonic development and ectopic implantation. LIF is believed to enhance early embryonic cell division, differentiation, and implantation. Researchers measured amounts of messenger RNA (mRNA) for making LIF in human Fallopian tubes and cell cultures of cells from Fallopian tubes removed during ectopic pregnancy. LIF mRNA was found in greatest quantity in the inner surface of the Fallopian tube and was markedly elevated in ectopic pregnancy. LIF mRNA production was stimulated by the substances that mediate inflammation, which suggests linkages among inflammation, LIF, and ectopic pregnancy.

Background: The most widely accepted criteria for the evaluation of prognosis of malignant melanoma are histopathologic and clinical presentation. No currently available laboratory tests provide additional prognostic information. It has recently been suggested that reverse transcription and polymerase chain reaction (RT-PCR)-based detection of tyrosinase messenger RNA (mRNA) in peripheral blood might be useful in the early detection of circulating tumor cells, since tyrosinase is thought to be a melanocyte-specific marker. Purpose: To further evaluate the clinical relevance of this potential marker, we examined peripheral blood samples from patients with malignant melanoma in different stages of disease for the presence of tyrosinase mRNA. Methods: Total cellular RNA was extracted from heparinized peripheral blood cells from 64 patients with malignant melanoma, from rive healthy control subjects, and from four patients with other cancers using the RANzol A method. For analysis of tyrosinase mRNA, RT-PCR was performed as previously described by Smith et al.; the sensitivity of this assay was tested using RNA extracted from human melanoma cells (SK-mel 1 and Sk-mel 3 cell lines) serially diluted with peripheral blood obtained from healthy control subjects. Two additional human melanoma cell lines (Sk-mel 30 and RPMI-7951) served as positive controls for RT-PCR detection of tyrosinase mRNA. Overall patient survival curves were constructed using Kaplan-meier estimates. Results: Tyrosinase mRNA was detected by RT-PCR assay of all four of the established melanoma cell lines tested. Nine of the 64 patients with malignant melanoma were found to have detectable tyrosinase mRNA in their peripheral blood cells (tyrosinase-positive patients). The 16 patients with localized primary melanoma did not have detectable tyrosinase mRNA in their peripheral blood cells. Among the 48 patients with metastatic disease, all 27 patients who exhibited no evidence of disease progression were tyrosinase negative. Notably, all nine tyrosinase-positive patients had visceral metastases and were found to exhibit disease progression at the time of the sampling. Four of the nine tyrosinase-positive patients were also found to test negative at times without evidence of progressive disease; one patient became negative after achieving stable disease and three became positive for tyrosinase transcripts on disease progression. The probability of survival from time of sampling was significantly lower in the nine tyrosinase-positive patients when tested versus the 23 patients with comparable disease but without detectable tyrosinase mRNA (two-sided; P[less than or equal to].05). Conclusions: The results of this study demonstrate that the detection of tyrosinase mRNA in cells in the peripheral blood by RT-PCR may be a useful prognostic marker for predicting tumor progression and poor clinical outcome in patients with malignant melanoma. [J Natl Cancer Inst 1996; 88:590-4]

High levels of HIV type 1 messenger RNA (mRNA) may be a biological marker of AIDS progression. HIV-infected people often do not develop serious AIDS symptoms for up to ten years. Researchers examined the blood cells of 150 HIV-infected men under 30 years old. Using the polymerase chain reaction, HIV-1 replications and CD4 cell counts predicted disease progression and early death up to eight years later. The higher the HIV mRNA expression, the lower the immune status or CD4 count. After three years, 69% of infected men with the highest mRNA counts had developed AIDS compared to only 6% of those with the lowest mRNA counts. After seven years, only 9% of those patients with very high mRNA counts survived compared to a 44% survival rate in men with lower mRNA counts. Men without detectable mRNA activity did not progress to AIDS during the same period.

Messenger ribonucleic acid (mRNA) for epidermal growth factor (EGF) receptor appears to be present in the fetal ovary and uterus at different stages of development. EGF receptor is a receptor for both EGF and transforming growth factor-alpha (TGF-alpha). A study examined the presence of mRNA for EGF receptor, EGF and TGF-alpha in fetal ovarian and uterine tissue at 10-, 15-, 19- and 22-weeks of development. mRNA for EGF receptor was found in both ovarian and uterine tissue at all four stages of development. mRNA for TGF-alpha was present in ovarian tissue at all four stages of development, but it was not found in uterine tissue at any stage of development. mRNA for EGF was found in both uterine and ovarian tissue at all four stages of development.

Background: Interactions between cells and the basement membrane glycoprotein laminin are altered during colon cancer progression. Colon carcinoma and normal mucosa cells express a variety of laminin-binding proteins, including the 67-kd laminin receptor (67 LR) and a 31-kd human laminin-binding protein (HLBP31) homologous to the 31-kd human IgE-binding protein/galactoside-binding lectin. Purpose: To investigate whether various laminin-binding proteins are differentially expressed in human colon carcinoma, we studied messenger RNA (mRNA) levels of the 67 LR and HLBP31 and matched tumor and adjacent normal mucosa samples from a series of 21 patients. Methods: Total cellular RNA from tumor and normal mucosa was isolated and analyzed by Northern and slot blot hybridization. In addition, HLBP31 proteins levels were assessed by the immunoblot technique. Quantitative laminin affinity chromatography was also used to measure the synthesis of HLBP31 protein in five human cancer cell lines. Results: The steady-state mRNA level of HLBP31 was downregulated (i.e., decreased) in 18 of 21 human colon carcinomas compared with the level in their corresponding normal colonic mucosa. On average, the level of HLBP31 mRNA was decreased 50% [+ or -] 30% ([+ or - SD]) in the colon cancers. The mean ratio of colon cancer HLBP31 mRNA to adjacent normal mucosa HLBP31 mRNA was twofold lower in primary tumors of patients with metastases (0.3 [+ or -] 0.2 SD) than in primary tumors of patients free of metastatic lesions (0.6 [+ or -] 0.2 SD). The differences between the two groups of patients were statistically significant (P

OBJECTIVE: Human placenta expresses receptors for transforming growth factor-[alpha] and epidermal growth factor throughout pregnancy. Experiments were performed to determine whether epidermal growth factor or transforming growth factor-[alpha] might be synthesized by placental cells and act through an autocrine. mechanism to influence functioning of placental cells in vivo. STUDY DESIGN: Human placentas from early, mid, and late gestations were analyzed for transforming growth factor-[alpha] and epidermal growth factor messenger ribonucleic acid and proteins. Polyadenylic acid-positive ribonucleic acid was isolated from placentas from 10, 11, 13, 21, 32, 38, 39, and 40 3weeks of gestation and analyzed by Northern analysis for hybridization with complementar deoxyribonucleic acid probes specific for epidermal growth factor or transforming growth factor-[alpha]. Levels of immunoreactive epidermal growth factor and transforming growth factor-[alpha] were measured by specific radioimmunoassays in pools of placentas from early, mid, and late gestations, and levels of epidermal growth factor and transforming growth factor-[alpha] receptor-active protein were measured by radioreceptor assay. RESULTS: All placentas had a strong transforming growth factor-[alpha] hybridization band at 4.5 kb and a weak epidermal growth factor hybridization band at 5.2 kb. High levels of transforming growth factor-[alpha] immunoreactive protein (90 to 180 ng/mg protein) and low levels of immunoreactive epidermal growth factor (3 to 9 pg/mg protein) were detected in pools of placentas from early, mid, and late gestations. High levels of epidermal growth factor and transforming growth factor-[alpha] receptor-active protein (250 ng/mg protein) were also detected. CONCLUSION: Human placentas contain relatively high levels of immunoreactive and receptor-active transforming growth factor-[alpha], as well as transforming growth factor-[alpha] messenger ribonucleic acid, throughout gestation. This finding suggests that transforming growth factor-[alpha may act by an autocrine system to influence human placental cell function in vivo. (Am J Obstet Gynecoe 1992;166:192-9.)