M. Satya Murthy

Breast cancer patient's cell-mediated immune response to thomsen-friedenreich (T) antigen

Thomsen‐Friedenreich (T) antigenic specificity as determined with human serum anti‐T was found in reactive form in breast adenocarcinomata but not in healthy and generally not in benign breast tissues. T‐antigenic specificity was demonstrable in all metastatic breast carcinoma lesions. T specificity was also present in adeno‐ and squamous cell carcinomata from other organs; it was not found in the four melanomata, one glioblastoma, and seven benign non‐breast tumors. Breast carcinoma patients but not healthy people showed cellular immunity to T antigen in vivo and in vitro. Most striking was the delayed‐type cutaneous hypersensitivity reaction that was positive in over 85% of the ductal breast carcinoma patients tested, negative in over 94% benign breast disease patients, and in all presumably healthy individuals investigated. T antigen is readily available from healthy human red blood cells in uncontaminated form, and free of HL‐A and Australia antigens.

Influence of smoking on the development of lung metastases from breast cancer

Background. This study examined the association between cigarette smoking status and the development of lung metastases in a group of 835 women diagnosed with primary malignant unilateral breast cancer.

Growth and metastasis of human breast cancers in athymic nude mice

To evaluate critically the merit of utilizing a wound model for growing human tumors, a series of increasingly difficult human tumor types were tested for growth at sites of trauma in athymic nude mice. In vitro tumor lines as well as fresh tumors from the breast, colon, rectum, lung, and a metastasis from an unknown primary were intraperitoneally injected into mice subjected to intra-abdominal organ injury. Successful xenografts were obtained from nine of 10 cell lines and 14 of 24 fresh tumors. The latter included five of six (83%) colon cancers, one lung tumor, metastatic tumor of unknown primary, three of four (75%) metastatic breast cancers and four of six (67%) estrogen receptor (ER)-negative breast primary tumors. Six ER-positive breast tumors tested failed to grow in mice without estrogen supplementation. Xenografts from two breast, two colon and the lung cancers formed spontaneous metastases and all xenografts tested were able to yield serial transplants in the surgical wound model. Histologically, all xenografts and their metastases were identical to their respective donor tumors. Transplantability in mice without exogenous estrogen supplementation was linked to the absence of estrogen and progesterone receptors in breast tumors. Transplantability of the cell lines was associated with the expression of cell surface receptors for fibronectin and hyaluronic acid. Receptors for other extracellular matrix components, namely, laminin, vitronectin, collagen, fibrinogen or von Willebrand factor were not associated with transplantability. These results demonstrate that a large proportion of human tumors, including the breast tumors, can be successfully xenografted into athymic mice by providing them with a healing wound environment, and that such xenografts grown at ectopic sites exhibit metastatic ability.

Inhibition of tumor implantation at sites of trauma by plasminogen activators

The authors report on the influence of plasminogen activators (PA) on implantation of TA3Ha mammary tumor cells in the healing hepatic wounds of syngeneic strain A mice. Intravenously injected TA3Ha cells, although they rarely metastasize to the liver, formed tumors in the hepatic wounds of a significant percent (42%, P < 0.0001) of mice. The frequency of tumor formation declined as the interval between surgery and tumor cell inoculation was increased. Furthermore, preexposure of cells to fibrinogen, fibronectin, laminin, or peptides containing the arginine – glycine – aspartic acid – serine residues dramatically reduced the frequency of tumor formation in the hepatic wounds. These results indicate that TA3Ha cells interact with fibrinogen‐related proteins in the wound to aid their attachment and growth. Because these proteins are susceptible to digestion by plasmin, PA were used in this study to examine whether administration of these drugs to the mice would modulate tumor formation in the liver wounds. Among the PA tested, human plasmin B‐chain – streptokinase complex (B‐SK) and recombinant tissue plasminogen activator (t‐PA) inhibited tumor implantation in a dose‐related manner. Administration of 900 units (U) of B‐SK or 3300 U of t‐PA per mouse reduced the frequency of tumor formation from 42% to 0% (P = 0.02) and 11% (P = 0.02), respectively. The B‐SK was complexed with p‐nitrophenyl‐p‐guanidinobenzoate; it did not activate the plasminogen or inhibit tumor formation in the hepatic wounds. Although urokinase activated the plasminogen, it did not inhibit tumor implantation in the hepatic wound. Heparin, an anticoagulant that prevents conversion of fibrinogen to fibrin without being fibrinolytic, had no influence on tumor formation in the hepatic wounds. The PA can generate plasmin that digests the cell attachment proteins in wounds and consequently inhibits tumor cell attachment.

The role of fibronectin in tumor implantation at surgical sites

Fibronectins are a family of glycoproteins with modular functional domains. They mediate cell-cell and cell-matrix interactions which are important in embryogenesis, wound healing, metastasis and other processes. We present data on the influence of fibronectin on wound implantation of a murine mammary carcinoma line, TA3Ha. Fibronectin used in these studies was derived from bovine plasma, human serum, human foreskin fibroblasts, and mouse embryo cultures. TA3Ha cells rarely form tumors in the liver of syngeneic mice when injected intravenously but after hepatic wedge resection, 45% (107/240) of the mice develop tumors in the hepatic wound. Wound implantation is markedly reduced when the cells are pre-exposed to 200 µg/ml bovine plasma fibronectin (13%, P = 0.007), human serum fibronectin (0%, P = 0.02), human cellular fibronectin (0%, P = 0.02), or mouse cellular fibronectin (0%, P = 0.04). Lung colonization is also reduced by these fibronectins. These effects are not due to a cytotoxic action of fibronectin, since intraperitoneally injected fibronectin-treated cells form ascites tumor as effectively as do control untreated cells. Local application of a solution containing 0.25 mg/ml mouse cellular fibronectin to the hepatic wound reduces the frequency of tumor implantation from 45% to 5% (1/21, P = 0.001). No tumor implantation inhibition is seen when only suspending medium or albumin in suspending medium is used. The mechanism by which topical application of fibronectin reduces hepatic wound implantation of tumor cells is unclear, but this finding raises an exciting possibility of preventing local recurrence of cancer.

The potential role of integrin receptor subunits in the formation of local recurrence and distant metastasis by mouse breast cancer cells.

The mechanisms by which surgical injury fosters tumor growth are examined.

Inhibition of tumor implantation at sites of trauma by Arg-Gly-Asp containing proteins and peptides

We report on the inhibition of wound implantation by TA3Ha mammary carcinoma cells by Arg-Gly-Asp containing proteins and peptides using a hepatic wedge resection model. Intravenously injected TA3Ha cells rarely form tumor in the liver of syngeneic mice, but after hepatic wedge resection, 45% (107/240) of the mice develop tumors in the hepatic wound. Hepatic wound implantation is significantly (P = 0.01) inhibited by pretreating the cells with whole mouse plasma, but not with fibrinogen-depleted plasma or serum. Tumor inhibition is also achieved by pretreatment of cells with fibrinogen (P = 0.05–0.0004), fibronectin (P = 0.007) and laminin, but not by albumin. The active domain appears to be the RGDS sequence since the deca- and tetrapeptides containing RGDS inhibit wound implantation (P < 0.05). However, the tetrapeptide Arg-Gly-Glu-Ser has no such activity. None of these agents affects ascites tumor formation by the intraperitoneally injected cells, suggesting that anchorage independent growth of cells is not affected. We propose that proteins and peptides containing RGD occupy the binding sites and prevent the cells from interacting with cell adhesion proteins in healing wounds. Proteins and/or peptides containing RGD may be useful for preventing local recurrence in postsurgical cancer patients.

Pre‐, peri‐, and postoperative chemotherapy for breast cancer: Is one better than the other?

The purpose of the present study was to determine the relative efficacy of pre‐, peri‐, and postoperative chemotherapy in the prevention of breast cancer relapse and prolongation of host survival. The studies were performed using an experimental mouse breast cancer model. TA3Ha mouse mammary adenocarcinoma was transplanted into the mammary fat pad of syngeneic mice to obtain tumors in their natural organ. The tumors were surgically excised with a “curative” intent. A single treatment with 10 mg/kg doxorubicin was given intravenously pre‐, peri‐, or postoperatively. Among 74 mice whose tumors were resected but no doxorubicin was given, local recurrence, axillary metastasis, and lung metastasis were seen in 43%, 37%, and 16% of the mice, respectively. Seventeen (23%) mice had no evidence of disease. Doxorubicin given 4 days preoperatively reduced the rate of growth of primary tumor. Local recurrence was reduced in these mice by 30% and metastasis to the axillary lymph nodes and lung was completely prevented. Disease‐free survival was increased to 70% (P < 0.01). Similar beneficial effects were obtained when chemotherapy was administered 2 days prior to surgery. The peri‐operative chemotherapy group showed 8% (2/26) local recurrence, 4% axillary metastasis, and 0% lung metastasis. Proportion of mice without any evidence of disease increased to 92% (P < 0.00001). Chemotherapy given 4 days postoperatively resulted in 63% (10/16) local recurrence, 38% axillary metastasis, and 6.3% lung metastasis. Only 38% of the mice were disease‐free. Thus in the model studied, perioperative chemotherapy offers the best chance for reduced recurrence and for improved disease‐free survival.