Install Postfix and Procmail:
yum install postfix
yum install procmail

(Optional)Setup mail relay: /etc/postfix/main.cf
relayhost = [Relay server IP]

Setup procmail: /etc/postfix/main.cf
mailbox_command = /usr/bin/procmail

Configuration: $HOME/.procmailrc
PATH=/usr/local/bin:/bin:/usr/bin
LOGFILE=$HOME/procmail.log
VERBOSE=YES
SHELL=/bin/sh
:0
* ^Subject:.*BANK*
| $HOME/sendmail.php

PHP script: $HOME/sendmail.php
#!/usr/bin/php
<?php
$to      = 'my@gmail.com';
$subject = 'Test email bank';
$message = '';
$headers = 'From: my@gmail.com' . "\r\n" .
    'Reply-To: my@gmail.com' . "\r\n" .
    'X-Mailer: PHP/' . phpversion();
$stdin = fopen('php://stdin', 'r');
$line = fgets($stdin);
$message .= $line;
mail($to, $subject, $message, $headers);
?>