Joel Lundy

Expression of ras Oncogene p21 in Prostate Cancer

The major neoplastic transformation-inducing genes of human solid tumors are members of the ras oncogene family. We used an immunohistochemical assay to assess expression of both the unaltered and the mutated ras oncogene protein (p21) in normal and neoplastic prostatic cells. With the concentration of monoclonal antibody used in this study, epithelial and stromal cells from subjects with normal prostates and from 19 patients with benign prostatic hyperplasia were negative for p21 antigen. This antigen was detected in 2 of 6 prostates with Grade I carcinoma, 4 of 6 with Grade II, and all of 17 with higher grades. A semiquantitative immunohistochemical method demonstrated that expression of the p21 antigen in a carcinoma strongly correlated with nuclear anaplasia and was inversely related to the degree of glandular differentiation. However, markedly anaplastic tumors were often more heterogeneous in expression of p21 and contained areas of low staining for the antigen. Comparison of p21 antigen with tumor carcinoembryonic antigen and prostate-specific antigen demonstrated that ras p21 was the only phenotypic marker that correlated with histologic tumor grade. Thus, ras oncogene p21 may represent a new class of biologically relevant tumor markers and may be a useful adjunct to histopathologic examination in determining the prognosis of patients with prostate cancer.

ras p21 Expression in the progression of breast cancer

The differential expression of the ras oncogene product p21 in the primary tumor, regional nodes, and distant metastatic sites in patients with disseminated breast cancer was examined to define the biologic and clinical significance of the ras oncogene in the progression of breast cancer. The avidin-biotin peroxidase complex method was used on formalin-fixed, paraffin-embedded tissues from 16 patients with metastatic disease. The primary antibody used in this protocol was RAP-5, an anti-p21 murine monoclonal IgG2a. p21 antigen staining was similar in the primary tumor and regional nodes from the same patient (P less than 0.05), but the staining of distant metastases was more variable. Expression of ras p21 was consistently increased in invasive components of the primary tumor as compared with intraductal tumor. In addition, a high level of p21 expression was seen in tumor emboli in lymphatics and blood vessels as compared with contiguous tumor in parenchymal tissue. Although p21 staining is present in aggressive primary breast cancers and most metastatic sites, our findings indicate that markedly enhanced p21 expression is associated with the earlier stages (invasion and dissemination) of aggressive breast cancers.

Monoclonal antibody DF3 correlates with tumor differentiation and hormone receptor status in breast cancer patients.

SummaryThe murine monoclonal antibody (MAb) designated DF3, reacts with a 300-kd human mammary epithelial antigen which is expressed on apical borders of secretory mammary epithelial cells and in the cytosol of less differentiated malignant cells. Human mammary tumors have been evaluated for the level of DF3 antigen as a correlate to clinicopathologic parameters related to degree of tumor differentiation: nuclear grade (NG), histologic grade (HG), and estrogen receptor status (ER). More DF3 antigen was present in breast carcinomas with NG 1 and 2 as compared to tumors with NG 3 (p = .002). Similarly DF3 antigen presence was greater in HG 1 and 2 tumors than in HG 3 (p<.001). The results also demonstrate that quantitative differences in the presence of the DF3 differentiation antigen correlate with estrogen receptor status. Twenty-two of 23 ER positive tumors were also DF3 positive. Only 6 of 23 ER negative tumors were reactive to MAb DF3 (p<.001). There was, however, no correlation between DF3 reactivity and absolute levels of estrogen or progesterone receptor.These findings confirm our hypothesis that MAb DF3 reacts to a differentiation antigen present in some human breast carcinomas. The DF3 antigen phenotype can serve as an independent phenotypic marker with correlations to standard indicators of degree of differentiation and estrogen receptor status of infiltrating ductal carcinomas of the breast, and should thus be evaluated as a prognostic indicator in breast cancer patients. The data also suggests that DF3 histochemistry may be a useful alternative in assessing estrogen receptor status of small breast cancers where there is an insufficient amount of tumor present for biochemical assay of hormone receptor levels.

Elevated ras oncogene expression correlates with lymph node metastases in breast cancer patients.

The protein product of the ras cellular oncogene(s) (p21) was assayed in primary breast carcinomas from two groups of patients who had different axillary lymph node status. Using an immunohistochemical assay, the intensity and percent of neoplastic cells demonstrating ras p21 antigen staining were significantly higher in the primary tumors from patients with lymph nodes positive (LN+) for malignancy (20 patients) compared with the lymph node negative (LNO) group (21 patients). The expression of p21 also correlated with tumor size. Age and estrogen receptor status did not influence p21 staining. The antigen expression of p21 was similar in intensity and distribution in the primary tumor and regional lymph node metastases. Enhanced expression of p21 in primary breast cancers that metastasize to regional nodes indicates that ras p21 may be a determinant of the malignant potential of breast cancer cells and may represent a new class of more biologically relevant tumor markers.

Immune impairment and metastatic tumor growth. The need for an immunorestorative drug as an adjunct to surgery

A spontaneous murine metastatic tumor system was used as a model to assess the effects of a major surgical procedure on tumor‐specific immune reactivity and the growth of micrometastases. Any major surgical procedure resulted in impaired cell‐mediated cytotoxicity postoperatively and an increase in the number of gross pulmonary metastases. The use of an immunorestorative drug, Thiabendazole, in the perioperative period resulted in an improved cytotoxic response and a significant decrease in pulmonary metastases. Perioperative immunotherapy can be an effective adjunct to surgery in preventing the growth of micrometastatic foci. Cancer 43:945–951, 1979.

β-Endorphin Injected into the Nucleus of the Raphe Magnus Facilitates Metastatic Tumor Growth

Electrical stimulation of the periaqueductal gray of the rats midbrain analgesia leads to an increase in the number of artificial pulmonary metastases from the Walker 256 tumor. In an effort to investigate the influence of the pain suppression system and its associated peptides on this phenomenon, we activated the pain suppression system directly from the Nucleus of the Raphe Magnus, a non-opioid subsystem. After inducing analgesia by direct injection of beta-endorphin on the Nucleus of the Raphe Magnus, we noted an increase in the number of artificial pulmonary metastases. This result could be blocked by pretreatment with naloxone. If the Nucleus of the Raphe Magnus was activated by electrical stimulation sufficient to induce analgesia, the metastatic effect was still present but markedly attenuated.

The effect of thiabendazole in a mixed leukocyte culture.

The effect of thiabendazole (TBZ), an anthelmintic, on a mixed leukocyte culture was assessed. Following i.p. administration of TBZ at a dose of 20 mg/kg to C57BL/6 mice, spleen cells were harvested and reacted in a one-way mixed leukocyte culture with irradiated BALB/c stimulator cells. When TBZ was administered 24 hr before the animals were killed, the proliferative response of spleen cells after 5 days in culture was greater than two times that of responder cells from normal, untreated C57BL/6 mice; the reactivity of spleen cells harvested 48 hr after TBZ administration was not statistically different from controls. Although proliferative response of normal responder cells reached a peak on day 6, TBZ treatment 24 hr before the mice were killed caused spleen cells to reach a proliferate peak on day 3. The magnitude of this peak was three times the normal proliferative peak on day 6. The population of spleen cells affected by TBZ is in the plastic-adherent fraction, and the drug effect can be transferred to normal responder lymphocytes by the addition of peritoneal exudate cells from TBZ-treated mice.

Thiabendazole (TBZ), an immunohemomodulator II. Effects on thymocytes and prothymocytes

The purpose of this study was to document the effects of TBZ on the early stages of T cell maturation. The method utilized to quantify presumptive thymocyte progenitors in the bone marrow used the enzyme terminal deoxynucleotidyl transferase (TdT) as a marker. Shifts in thymocyte populations were determined by quantitative planimetry, immunofluorescence for TdT and tritiated thymidine incorporation. When given alone, TBZ produced a marked increase in the number of large, mitotically active lymphoblasts in the thymus cortex. When given with DNFB, a thymus-dependent neoantigen, TBZ produced a significant increase in TdT-positive bone marrow cells. In a companion study, TBZ + DNFB were found to stimulate T cells in lymph node and spleen. Hence, the results indicate that under appropriate conditions, TBZ can stimulate all stages of T cell differentiation in mice.

Thiabendazole (TBZ), an immunohemomodulator. I. Effects on lymph node and spleen.

Previous studies in our laboratory with Thiabendazole (TBZ) indicated that the drug significantly augmented cellular immune responses in mice. The purpose of the present and companion study was to determine which of the cell populations in primary and secondary lymphoid organs and in bone marrow were affected by the in-vivo administration of TBZ. Two major changes in lymph nodes and/or spleens of TBZ-treated mice were detected by histological and quantitative planimetric analysis: (1) expansion of T and B lymphocyte compartments and (2) increase in extramedullary hemopoiesis. The effect on T cells and on hemopoiesis were observed only when TBZ was administered with the thymus-dependent neoantigen, dinitrofluorobenzene (DNFB). The effect on B cells appeared to be antigen-independent. Increased extramedullary hemopoiesis in TBZ + DNFB-treated mice was preceded by a significant increase in pluripotent hemopoietic stem cell activity in bone marrow, as measured by the CFU-S assay. This study indicates that TBZ has significant effects on the development and differentiation of both lymphoid and hemopoietic cells.